Biocompatible locust bean gum as mesoporous carriers for naproxen delivery - Cordeiro, Teresa; Ana B. Paninho; Bernardo, Maria; Matos, Inês; Carolina V. Pereira; Ana Teresa Serra; Matias, Ana; Márcia G. Ventura (Materials Chemistry and Physics, 2020)
The work reports the impregnation of naproxen into locust bean gum mesoporous matrixes with different textural properties. The matrixes were prepared through the dissolution of the biopolymer in water and in two ionic liquids (ILs): [bmim][Cl] and [C2OHmim][Cl] and dried with scCO2. The poor water-soluble pharmaceutical drug naproxen was loaded into the matrixes and the composites were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy and by differential scanning calorimetry; the results were compared with neat ILs and drug. The naproxen release from the matrixes was attempted at pH 7.4. Sustained release of naproxen in the different composites occurs, and consequently the naproxen release has lower rates compared with neat crystalline naproxen dissolution. Nevertheless, it was possible to observe small differences on release profiles for the studied composites. The higher release rate was observed for the composite where [bmim][Cl] was used as solvent, for which the calorimetric analysis revealed full amorphization of the incorporated drug. Cytotoxicity assays reveal that cellular viability in Caco-2 cells is preserved. This fact allied with the biocompatibility of locust bean gum allow for the composites potential application as naproxen controlled/sustained delivery systems with higher drug bioavailability achieved through naproxen amorphization.
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Keywords: Amorphous state; Drug loading; Drug release; DSC; Locust bean gum mesoporous matrixes

Development of a model for an industrial acetylene hydrogenation reactor using plant data – Part I - Bruna Rijo; Francisco Lemos; Fonseca, Isabel; André Vilelas (Chemical Engineering Journal, 2020)
In this work, a dynamic model of an industrial acetylene hydrogenation reactor with a front-end configuration was developed, based on plant operation data. This type of reactor operates in transient state, not only due to the natural fluctuations in operating conditions but also due to the effects caused by the deactivation of the catalyst. To develop the dynamic model of the acetylene hydrogenation reactor a thorough study of the effect of operating conditions was performed; the influence of variables such as the inlet temperature of the 1st reactor, the flowrate, carbon monoxide concentration, on the activity, selectivity and stability of the catalyst was examined by choosing adequate periods of the operation of the reactor. To understand the reaction mechanism of this system, several published kinetics were tested but only one was finally fitted to the industrial data, to interpret the operation of the acetylene hydrogenation reactor. A set of operation periods was used to develop the model which was then validated by applying the model to a different set of operation periods. As a conclusion, the dynamic model that was developed and validated, using actual plant operation data, was able to adequately describe the outlet temperatures of the three reactors in the system as well as the outlet acetylene concentration of the 3rd reactor.
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Keywords: Acetylene hydrogenation; Carbon monoxide; Dynamic model; Front-end configuration

Flexible and Structural Coloured Composite Films from Cellulose Nanocrystals/Hydroxypropyl Cellulose Lyotropic Suspensions - Saraiva, Diogo V.; Chagas, Ricardo; Abreu, Beatriz M. de; Gouveia, Cláudia N.; Silva, Pedro E. S.; Godinho, Maria Helena; Fernandes, Susete N. (Crystals, 2020)
Lyotropic colloidal aqueous suspensions of cellulose nanocrystals (CNCs) can, after solvent evaporation, retain their chiral nematic arrangement. As water is removed the pitch value of the suspension decreases and structural colour-generating films, which are mechanically brittle in nature, can be obtained. Increasing their flexibility while keeping the chiral nematic structure and biocompatible nature is a challenging task. However, if achievable, this will promote their use in new and interesting applications. In this study, we report on the addition of different amounts of hydroxypropyl cellulose (HPC) to CNCs suspension within the coexistence of the isotropic-anisotropic phases and infer the influence of this cellulosic derivative on the properties of the obtained solid films. It was possible to add 50 wt.% of HPC to a CNCs aqueous suspension (to obtain a 50/50 solids ratio) without disrupting the LC phase of CNCs and maintaining a left-handed helical structure in the obtained films. When 30 wt.% of HPC was added to the suspension of CNCs, a strong colouration in the film was still observed. This colour shifts to the near-infrared region as the HPC content in the colloidal suspension increases to 40 wt.% or 50 wt.% The all-cellulosic composite films present an increase in the maximum strain as the concentration of HPC increases, as shown by the bending experiments and an improvement in their thermal properties.
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Glycerol conversion into biofuel additives by acetalization with pentanal over heteropolyacids immobilized on zeolites - Castanheiro, J. E.; Vital, J.; I. M. Fonseca; A. M. Ramos (Catalysis Today, 2020)
Dodecamolydbophosphoric acid (HPMo) immobilized on USY zeolite was used as a catalyst for the acetalization of glycerol with pentanal at 70 °C. Catalysts were prepared with different amounts of heteropolyacid, and the most active sample was the HPMo2@Y catalyst (1.1 wt.%). The products of glycerol acetalization with pentanal were (2-butyl-1,3-dioxolan-4-yl)methanol, a five-member ring compound, and 2-butyl-1,3-dioxan-5-ol, a six-member ring compound. Good values of selectivity for the five-member ring compound (80–85%) were obtained with all materials. The reaction conditions were optimized using HPMo2@Y as a catalyst. The optimal conditions were determined to be 70 °C reaction temperature with 0.3 g catalyst and a 1:2.5 M ratio of glycerol to pentanal. The catalytic stability of HPMo2@Y was studied. The acetalization of glycerol with pentanal was performed using the same sample. High catalytic activity for HPMo2@Y was observed.
The Green Catalytic Processes Special Issue on the 6th International Congress on Green Process Engineering
Keywords: Acetalization; Glycerol; Green processes; Heterogeneous catalysis; Heteropolyacids

Kinetics and Mechanism of Mineral Respiration: How Iron Hemes Synchronize Electron Transfer Rates - Chabert, Valentin; Babel, Lucille; Füeg, Michael P; Karamash, Maksym; Madivoli, Edwin S; Herault, Nelly; Joana M Dantas; Salgueiro, , Carlos A.; Giese, Bernd; Fromm, Katharina M (Angewandte Chemie International Edition, 2020)
Abstract Anaerobic microorganisms of the Geobacter genus are effective electron sources for the synthesis of nanoparticles, for bioremediation of polluted water, and for the production of electricity in fuel cells. In multistep reactions, electrons are transferred via iron/heme cofactors of c-type cytochromes from the inner cell membrane to extracellular metal ions, which are bound to outer membrane cytochromes. We measured electron production and electron flux rates to 5×105 e s−1 per G. sulfurreducens. Remarkably, these rates are independent of the oxidants, and follow zero order kinetics. It turned out that the microorganisms regulate electron flux rates by increasing their Fe2+/Fe3+ ratios in the multiheme cytochromes whenever the activity of the extracellular metal oxidants is diminished. By this mechanism the respiration remains constant even when oxidizing conditions are changing. This homeostasis is a vital condition for living systems, and makes G. sulfurreducens a versatile electron source.
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Keywords: Electron transfer; GEOBACTER sulfurreducens; iron heme; silver nanoparticles; silver proteins

Modulation of the Redox Potential and Electron/Proton Transfer Mechanisms in the Outer Membrane Cytochrome OmcF From Geobacter sulfurreducens - Liliana R. Teixeira; Cordas, Cristina M.; Fonseca, Marta P.; Norma E.C. Duke; Pokkuluri, Phani Raj; Salgueiro, , Carlos A. (Frontiers in Microbiology, 2020)
The monoheme outer membrane cytochrome F (OmcF) from Geobacter sulfurreducens plays an important role in Fe(III) reduction and electric current production. The electrochemical characterization of this cytochrome has shown that its redox potential is modulated by the solution pH (redox-Bohr effect) endowing the protein with the necessary properties to couple electron and proton transfer in the physiological range. The analysis of the OmcF structures in the reduced and oxidized states showed that with the exception of the side chain of histidine 47 (His47), all other residues with protonatable side chains are distant from the heme iron and, therefore, are unlikely to affect the redox potential of the protein. The protonatable site at the imidazole ring of His47 is in the close proximity to the heme and, therefore, this residue was suggested as the redox-Bohr center. In the present work, we tested this hypothesis by replacing the His47 with non-protonatable residues (isoleucine – OmcFH47I and phenylalanine – OmcFH47F). The structure of the mutant OmcFH47I was determined by X-ray crystallography to 1.13 Å resolution and showed only minimal changes at the site of the mutation. Both mutants were 15N-labeled and their overall folding was confirmed to be the same as the wild-type by NMR spectroscopy. The pH dependence of the redox potential of the mutants was measured by cyclic voltammetry. Compared to the wild-type protein, the magnitude of the redox-Bohr effect in the mutants was smaller, but not fully abolished, confirming the role of His47 on the pH modulation of OmcF’s redox potential. However, the pH effect on the heme substituents’ NMR chemical shifts suggested that the heme propionate P13 also contributes to the overall redox-Bohr effect in OmcF. In physiological terms, the contribution of two independent acid–base centers to the observed redox-Bohr effect confers OmcF a higher versatility to environmental changes by coupling electron/proton transfer within a wider pH range.
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Molecular basis for the preferential recognition of β1,3-1,4-glucans by the family 11 carbohydrate-binding module from Clostridium thermocellum - Ribeiro, Diana O.; Viegas, Aldino; Pires, Virgínia M R; Medeiros-Silva, João; Bule, Pedro; Chai, Wengang; Marcelo, Filipa; Fontes, Carlos M. G. A.; Cabrita, Eurico J.; Palma, Angelina S.; Ana Luísa Carvalho (The FEBS Journal, 2020)
Understanding the specific molecular interactions between proteins and β1,3-1,4-mixed-linked d-glucans is fundamental to harvest the full biological and biotechnological potential of these carbohydrates and of proteins that specifically recognize them. The family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11) is known for its binding preference for β1,3-1,4-mixed-linked over β1,4-linked glucans. Despite the growing industrial interest of this protein for the biotransformation of lignocellulosic biomass, the molecular determinants of its ligand specificity are not well defined. In this report, a combined approach of methodologies was used to unravel, at a molecular level, the ligand recognition of CtCBM11. The analysis of the interaction by carbohydrate microarrays and NMR and the crystal structures of CtCBM11 bound to β1,3-1,4-linked glucose oligosaccharides showed that both the chain length and the position of the β1,3-linkage are important for recognition, and identified the tetrasaccharide Glcβ1,4Glcβ1,4Glcβ1,3Glc sequence as a minimum epitope required for binding. The structural data, along with site-directed mutagenesis and ITC studies, demonstrated the specificity of CtCBM11 for the twisted conformation of β1,3-1,4-mixed-linked glucans. This is mediated by a conformation–selection mechanism of the ligand in the binding cleft through CH-π stacking and a hydrogen bonding network, which is dependent not only on ligand chain length, but also on the presence of a β1,3-linkage at the reducing end and at specific positions along the β1,4-linked glucan chain. The understanding of the detailed mechanism by which CtCBM11 can distinguish between linear and mixed-linked β-glucans strengthens its exploitation for the design of new biomolecules with improved capabilities and applications in health and agriculture. Database Structural data are available in the Protein Data Bank under the accession codes 6R3M and 6R31.
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Keywords: 3-1; 4-mixed-linked glucans; carbohydrate specificity; carbohydrate-binding module; cellulosome; Clostridium thermocellum; β1

Multi-component adsorption study by using bone char: modelling and removal mechanisms - Regiane C. Ferreira; Diogo Dias; Fonseca, Isabel; Bernardo, Maria; João Lourenço Castagnari Willimann Pimenta; Nuno Lapa; Maria A. S. D. de Barros (Environmental Technology, 2020)
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PMID: 32744169

On operation of reverse electrodialysis (RED) and membrane capacitive deionisation (MCDI) with natural saline streams: A critical review - Sylwin Pawlowski; Rosa M. Huertas; Cláudia F. Galinha; João G. Crespo; Velizarov, Svetlozar (Desalination, 2020)
Environment-friendly production of power and clean water is one of the major goals of 2030 Agenda for Sustainable Development, and can be achieved by emerging electromembrane processes, such as reverse electrodialysis (RED) and membrane capacitive deionisation (MCDI). RED generates electricity from salinity gradient energy sources, while MCDI desalinates (mainly) brackish water. However, fouling, scaling, stack channels clogging and undesired uphill ionic transport can reduce the power output and salt removal efficiency in RED and MCDI, respectively. A practical overview of current problems and challenges of operating and monitoring these processes under real conditions is provided. Appropriate mitigation approaches, which might include feed water pre-treatment, in-situ cleaning strategies and/or development of new antifouling ion-exchange membranes (IEMs) are disclosed. First, a description, analysis and (when possible) normalised comparison of the performance of available RED and MCDI stacks, employing natural saline streams, is presented. Afterwards, it is discussed how fouling formation can be detected, monitored and characterised, which is essential to implement effective pre-treatment and cleaning strategies. Finally, sustainable ways for preparation of appropriate IEMs are selected and presented.
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Keywords: Fouling; Ion exchange membranes (IEMs); Ionic transport; Membrane capacitive deionisation (MCDI); Reverse electrodialysis (RED)

Porous carbons derived from hydrothermally treated biogas digestate - Bernardo, Maria; Catalina Rodriguez Correa; Yvonne Ringelspacher; Gero C. Becker; Nuno Lapa; Fonseca, Isabel; Isabel A.A.C. Esteves; Andrea Kruse (Waste Management, 2020)
Porous carbons from digestate-derived hydrochar were produced, characterized and their performance to reclaim phosphate from water was evaluated as a preliminary approach to demonstrate their practical application. In a first step, the digestate was converted into hydrochars through hydrothermal carbonization by using two different pH conditions: 8.3 (native conditions) and 3.0 (addition of H2SO4). The resulting hydrochars did not present significant differences. Consecutively, the hydrochars were activated with KOH to produce activated carbons with enhanced textural properties. The resulting porous carbons presented marked differences: the AC native presented a lower ash content (20.3 wt%) and a higher surface area (SBET = 1106 m2/g) when compared with the AC-H2SO4 (ash content = 43.7 wt% SBET = 503 m2/g). Phosphorus, as phosphate, is a resource present in significative amount in wastewater, causing serious problems of eutrophication. Therefore, the performance of the porous carbons samples to recover phosphate – P(PO43−) – from water was evaluated through exploitation assays that included kinetic studies. The lumped model presented a good fitting to the kinetic data and the obtained uptake capacities were the same for both carbons, 12 mg P(PO43−)/g carbon. Despite the poorer textural properties of AC-H2SO4, this carbon was richer in Ca, Al, Fe, K, and Mg cations which promoted the formation of mineral complexes with phosphate anions. The results obtained in this work are promising for the future development of P(PO43−) enriched carbons that can be used thereafter as biofertilizers in soil amendment applications.
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Keywords: Biogas production; Biomass digestate; Hydrothermal carbonization; Nanoporous carbons; Phosphate recovery from water

Porous carbons-derived from vegetal biomass in the synthesis of quinoxalines. Mechanistic insights - M. Godino-Ojer; R. Blazquez-García; Matos, I.; M. Bernardo; I. M. Fonseca; E. Pérez Mayoral (Catalysis Today, 2020)
We report herein for the first-time acid biomass-derived carbons from vegetal biomass, with high developed porosity, prepared through integrating method comprising pyrolysis and surface phosphonation, able to efficiently catalyze the synthesis of quinoxalines from 1,2-diamines and α-hydroxi ketones, under aerobic conditions. The obtained results indicate that the reaction is mainly driven by a combination of acid function strength and textural properties in terms of conversion and selectivity. Furthermore, our experimental and theoretical observations suggest that the preferred reaction pathway for this transformation, in the presence of the investigated acid carbon catalysts, involves cascade reactions including imination reaction between reactants, successive imine-enamine and keto-enol tautomerisms, heterocyclization followed by dehydration, and aromatization. While the acid sites seem to be a relevant role in each reaction step, the system formed by activated carbon and molecular oxygen could be behind the last oxidative reaction to give the corresponding nitrogen heterocycles.
SI: Fascinating catalysis
Keywords: Computational methods; Fine chemicals; Nanocatalysts; Porous carbons; Quinoxalines

Properties of κ-carrageenan aerogels prepared by using different dissolution media and its application as drug delivery systems - Daniela A.S. Agostinho; Paninho, Ana I.; Cordeiro, Teresa; Nunes, Ana V. M.; Fonseca, Isabel M.; Carolina Pereira; Matias, Ana; Márcia G. Ventura (Materials Chemistry and Physics, 2020)
This work reports the synthesis of kappa-carrageenan aerogels using different dissolution and crosslinking media in order to evaluate its effects on the textural properties of the matrixes and further on the drug loading and release performance. The different aerogel samples were produced through the dissolution of the biopolymer in water with addition of potassium salts as crosslinking agents and, in two different ionic liquids (ILs) derived from imidazolium ion, being further dried with supercritical CO2. The samples were characterized by Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy (ATR-FTIR), Scanning Electron Microscopy (SEM), Nitrogen Adsorption-Desorption Analysis, Thermogravimetry (TGA) and Differential Scanning Calorimetry (DSC). The synthesized samples presented surface areas similar to the carrageenan aerogels being their structure constituted mainly by meso and macropores. The absence of ionic liquid in samples was demonstrated by DSC analysis and was corroborated by the cytotoxicity assays which revealed that cellular viability in Caco-2 cells was preserved. Tetracycline was used as a model drug and loaded in two of the prepared aerogels samples. The release experiments were performed with the composites to test in vitro drug release at physiologic pH. With a higher macroporosity, the kappa-carrageenan aerogel prepared by dissolution into ionic liquid showed a higher loading capacity than the one prepared by dissolution into water and a slightly higher release rate. The matrixes were considered to present a good potential to be used as biocompatible carriers on drug controlled delivery.
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Keywords: biocompatibility; Drug release; Kappa-carrageenan aerogels; Tetracycline

RNA Quantification Using Noble Metal Nanoprobes: Simultaneous Identification of Several Different mRNA Targets Using Color Multiplexing and Application to Chronic Myeloid Leukemia Diagnostics - Baptista, Pedro Viana (Nanoparticles in Biology and Medicine, 2020)
Nanotechnology provides new tools for gene expression analysis that allow for sensitive and specific characterization of prognostic signatures related to cancer. Cancer is a complex disease where multiple gene loci contribute to the phenotype. The ability to simultaneously monitor differential expression originating from each locus allows for a more accurate indication into the degree of cancerous activity than either locus alone. Metal nanoparticles have been widely used as labels for in vitro identification and quantification of target sequences. Here we describe the synthesis of nanoparticles with different noble metal compositions in an alloy format that are then functionalized with thiol-modified ssDNA (nanoprobes). We also show how such nanoprobes are used in a non-cross-linking colorimetric method for the direct detection and quantification of specific mRNA targets, without the need for enzymatic amplification or reverse-transcription steps. The different metals in the alloy provide for distinct absorption spectra due to their characteristic plasmon resonance peaks. The color multiplexing allows for simultaneous identification of different mRNA targets involved in cancer development. A comparison of the absorption spectra of the nanoprobe mixtures taken before and after induced aggregation of metal nanoparticles allows to both identify and quantify each mRNA target. We describe the use of gold and gold–silver alloy nanoprobes for the development of the non-cross-linking method to detect a specific BCR-ABL fusion gene (e.g., e1a2 and e14a2) mRNA target associated with chronic myeloid leukemia (CML) using 10 ng/μL of unamplified total human RNA. Additionally, we demonstrate the use of this approach for the direct diagnostics of CML. This simple methodology takes less than 50 min to complete after total RNA extraction with comparable specificity and sensitivity to the more commonly used methods.
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Keywords: Cancer; Colorimetric method; Gene Expression; Gold nanoparticles; Gold–silver alloy nanoparticles; mRNA detection; Nanoprobes

Singularities of Pyogenic Streptococcal Biofilms – From Formation to Health Implication - Alves-Barroco, Cinthia; Paquete-Ferreira, João; Santos-Silva, Teresa; Alexandra R. Fernandes (Frontiers in Microbiology, 2020)
Biofilms are generally defined as communities of cells involved in a self-produced extracellular matrix adhered to a surface. In biofilms, the bacteria are less sensitive to host defense mechanisms and antimicrobial agents, due to multiple strategies, that involve modulation of gene expression, controlled metabolic rate, intercellular communication, composition, and 3D architecture of the extracellular matrix. These factors play a key role in streptococci pathogenesis, contributing to therapy failure and promoting persistent infections. The species of the pyogenic group together with Streptococcus pneumoniae are the major pathogens belonging the genus Streptococcus, and its biofilm growth has been investigated, but insights in the genetic origin of biofilm formation are limited. This review summarizes pyogenic streptococci biofilms with details on constitution, formation, and virulence factors associated with formation.
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Synthesis, Crystal Structure, and DFT Study of Two New Dinuclear Copper(I) Complexes Bearing Ar-BIAN Ligands Functionalized with NO2 Groups - Outis, Mani; Rosa, Vitor; César A. T. Laia; João Carlos Lima; Barroso, Sónia; Ana Luísa Carvalho; Maria José Calhorda; Avilés, Teresa (European Journal of Inorganic Chemistry, 2020)
{Two new bis(aryl-imino)-acenaphthene, Ar-BIAN (Ar = 2
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Keywords: Copper(I); Crystal structure; Density Function Calculations; Functionalized Ar-BIAN; synthesis

Thermodynamic properties of triheme cytochrome PpcF from Geobacter metallireducens reveal unprecedented functional mechanism - Ferreira, Marisa R.; Fernandes, Tomás M.; Salgueiro, , Carlos A. (Biochimica et Biophysica Acta (BBA) - Bioenergetics, 2020)
The bacterium Geobacter metallireducens is highly efficient in long-range extracellular electron transfer, a process that relies on an efficient bridging between the cytoplasmic electron donors and the extracellular acceptors. The periplasmic triheme cytochromes are crucial players in these processes and thus the understanding of their functional mechanism is crucial to elucidate the extracellular electron transfer processes in this microorganism. The triheme cytochrome PpcF from G. metallireducens has the lowest amino acid sequence identity with the remaining cytochromes from the PpcA-family of G. sulfurreducens and G. metallireducens, making it an interesting target for structural and functional studies. In this work, we performed a detailed functional and thermodynamic characterization of cytochrome PpcF by the complementary usage of NMR and visible spectroscopic techniques. The results obtained show that the heme reduction potentials are negative, different from each other and are also modulated by the redox and redox-Bohr interactions that assure unprecedented mechanistic features to the protein. The results showed that the order of oxidation of the hemes in cytochrome PpcF is maintained in the entire physiological pH range. The considerable separation of the hemes' redox potential values facilitates a sequential transfer within the chain of redox centers in PpcF, thus assuring electron transfer directionality to the electron acceptors.
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Keywords: Electron transfer; Multiheme cytochromes; NMR; Redox characterization

Effective Zinc-Substituted Keggin Composite To Catalyze the Removal of Sulfur from Real Diesels under a Solvent-Free System - Ribeiro, Susana O.; Granadeiro, Carlos M.; Almeida, Pedro L; Pires, Joao; Valenca, Rita; Campos-Martin, Jose M.; Ribeiro, Jorge C.; Baltazar de Castro; Balula, Salete S. (Industrial & Engineering Chemistry Research, 2019)
{The Keggin phosphotungstate (PW12) and its zinc derivative (PW11Zn) were tested as oxidative catalysts for desulfurization processes using simulated and real diesels. These compounds were used as homogeneous catalysts, while the corresponding SBA-15 composites were used as heterogeneous catalysts. The comparison of their catalytic performance demonstrated that the zinc-substituted polyoxo-metalate is more efficient than the plenary PW12 structure. Additionally, using the heterogeneous PW11Zn@aptesSBA-15, the sustainability and catalytic efficiency was largely improved, allowing the total sulfur removal from model diesel after 1 h using a small amount of oxidant (H2O2/S = 4) under an oxidative solvent-free system. The desulfurization of real diesels was performed under similar conditions, achieving 87.8% of efficiency using the PW11Zn@aptesSBA-15 catalyst. Furthermore, the catalyst maintained its activity over consecutive desulfurization cycles. The cost-effective operational conditions achieved with PW11Zn@aptesSBA-15 turn this into a promising material to be used in an industrial scale to treat diesel.}
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Understanding the influence of carbon nanotubes on the flow behavior of liquid crystalline hydroxypropylcellulose: A Rheo-NMR study - Coro Echeverria; Almeida, Pedro L; Figueirinhas, Joao L.; Godinho, Maria H (POLYMER, 2019)
Hydroxypropylcellulose (HPC) is an important cellulose derivative that has been widely studied due to its water-solubility, biocompatibility and biodegradability, but even more significant due to its ability to form liquid crystalline phases. HPC is able to form, under certain conditions, chiral nematic (cholesteric) structures in water solutions. Previous work confirmed that films prepared from liquid crystalline HPC/water solutions (LC-HPC) gave rise to anisotropic networks, with similar mechanical and optical characteristics of Liquid Crystalline Elastomers (LCE), capable to respond to humidity. It was also demonstrated that the incorporation of carbon nanotubes (CNTs) significantly improved the actuator responsiveness. In the work presented herein, we investigate how the incorporation of carbon nanotubes affects the flow behavior of LC-HPC solutions, and thus the structure-properties relationship, through a detailed Rheo-NMR study. As observed from the results, when shearing the samples, the degree of order reached (maximum quadrupolar peak splitting) by LC-HPC solutions increases with CNT content. Regarding the subsequent relaxation process, only the incorporation of 0.01 wt% of CNTs (lowest content) contributes to a faster recovery of cholesteric structure.
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Mesoporous nanosilica-supported polyoxomolybdate as catalysts for sustainable desulfurization - Mirante, Fatima; Gomes, Neide; Branco, Luis C.; Cunha-Silva, Luis; Almeida, Pedro L; Pillinger, Martyn; Gago, Sandra; Granadeiro, Carlos M.; Balula, Salete S. (Microporous and Mesoporous Materials, 2019)
Mesoporous silica nanoparticles (MSNs) strategically functionalized were used to immobilize a homogeneous polyoxomolybdate catalyst {[}PMo12O40](3-) (PMo12), active but unstable. The PMo12@TBA-MSN composite (where TBA refers to surface-tethered tributylammonium groups) conferred high stability to the polyoxomolybdate catalytic center and displayed an increase in efficiency for the oxidative desulfurization (ECODS) of a diesel simulant under sustainable conditions (using H2O2 as oxidant and an ionic liquid, {[}BMIM]PF6, as solvent). Continuous reuse of the catalyst and ionic liquid solvent in consecutive ECODS cycles was successfully performed, avoiding the production of residual wastes. The performance of the PMo12@TBA-MSN catalyst improved upon its reuse, leading to complete desulfurization of a multicomponent model diesel containing benzothiophene derivatives after just 1 h of the catalytic stage of the process. The robust nature of the supported catalyst was indicated by characterization of the recovered solid which showed retention of the structural and chemical integrities.
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Oxidative desulfurization strategies using Keggin-type polyoxometalate catalysts: Biphasic versus solvent-free systems - Ribeiro, Susana O.; Granadeiro, Carlos M.; Almeida, Pedro L; Pires, Joao; Capel-Sanchez, Maria C.; Campos-Martin, Jose M.; Gago, Sandra; Baltazar de Castro; Balula, Salete S. (Catalysis Today, 2019)
Strategic polyoxometalate Keggin-type structural modification was performed to increase the oxidative catalytic performance to desulfurize model and real diesels. The most active lacunar structure {[}PW11O39](7-) (PW11) showed to complete desulfurize a simulated diesel after 60 min at 70 degrees C. Its application as homogeneous catalyst using a biphasic system 1: 1 diesel/acetonitrile needed to use an excess of oxidant (ratio H2O2/S = 8). The immobilization of the PW11 on amine-functionalized SBA-15 supports originated two heterogeneous catalysts PW11@aptesSBA-15 and PW11@tbaSBA-15. The best results were attained with the PW11@aptesSBA-15 catalyst showing identical oxidative desulfurization performance as the homogeneous analogue. As advantage, this heterogeneous catalyst promotes the complete desulfurization of simulated diesel using a solvent-free system, i.e. without the need of acetonitrile use. On the other hand, the same desulfurization efficiency could be achieved using half the amount of oxidant (H2O2/S = 4). The oxidative desulfurization of the real diesel achieved a remarkable 83.4% of efficiency after just 2 h. The recycling capacity of PW11@aptesSBA-15 catalyst was confirmed for eight consecutive cycles using the biphasic and the solvent-free systems. Its stability investigation demonstrates to be higher under the solvent-free system than the biphasic system, without practically any occurrence of PW11 leaching in the first case. On the other hand, the Venturello peroxocomplex {[}PO4\{W(O-2)(2)\}(4)](3-), recognized as active intermediate in the homogeneous biphasic system, was not identified in the heterogeneous catalytic systems.
8th World Congress on Oxidation Catalysis on Oxidation Processes - Challenges and Solutions (WCOC), Polish Acad Sci, Jerzy Haber Inst Catalysis & Surgace Chem, Krakow, POLAND, SEP 03-08, 2017}

Reversible water driven chirality inversion in cellulose-based helices isolated from Erodium awns - Ana P.C. Almeida; Querciagrossa, Lara; Silva, Pedro E. S.; Goncalves, Filipa; Canejo, Joao P; Almeida, Pedro L; Godinho, Maria Helena; Zannoni, Claudio (Soft Matter, 2019)
Among the movements observed in some cellulosic structures produced by plants are those that involve the dispersion and burial of seeds, as for example in Erodium from the Geraniaceae plant family. Here we report on a simple and efficient strategy to isolate and tune cellulose-based hygroscopic responsive materials from Erodium awns' dead tissues. The stimuli-responsive material isolated forms left-handed (L) or right-handed (R) helical birefringent transparent ribbons in the wet state that reversibly change to R helices when the material dries. The humidity-driven motion of dead tissues is most likely due to a composite material made of cellulose networks of fibrils imprinted by the plant at the nanoscale, which reinforces a soft wall polysaccharide matrix. The inversion of the handedness is explained using computational simulations considering filaments that contract and expand asymmetrically. The awns of Erodium are known to present hygroscopic movements, forming R helices in the dry state, but the possibility of actuating chirality via humidity suggests that these cellulose-based skeletons, which do not require complicated lithography and intricate deposition techniques, provide a diverse range of applications from intelligent textiles to micro-machines.
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Structural characterization and biological properties of silver(I) tris(pyrazolyl)methane sulfonate - Almeida, J.; Catarina Roma-Rodrigues; Mahmoud, Abdallah G.; Guedes da Silva, M. Fátima C.; Pombeiro, Armando J. L.; Martins, Luísa M. D. R. S.; Baptista, Pedro V; Fernandes, Alexandra R (Journal of Inorganic Biochemistry, 2019)
The water-soluble 1D helical coordination polymer [Ag(Tpms)]n (1) [Tpms = tris(pyrazolyl)methane sulfonate, −O3SC(pz)3; pz = pyrazolyl] was synthesized and fully characterized, its single-crystal X-ray diffraction analysis revealing the ligand acting as a bridging chelate N3-donor ligand. The antiproliferative potential of 1 was performed on two human tumour cell lines, A2780 and HCT116, and in normal fibroblasts, with a much higher effect in the former cell line (IC50 of 0.04 μM) as compared to the latter cell line and to normal fibroblasts. Compound 1 does not alter cell cycle progression but interferes with the adherence of A2780 cells triggering cell apoptosis. Apoptosis appears to occur via the extrinsic pathway (no changes in mitochondria membrane potential, reactive oxygen species (ROS) and pro-apoptotic (B-cell lymphoma 2 (BCL-2) associated protein (BAX))/anti-apoptotic (BCL-2) ratio) being this hypothesis also supported by the presence of silver mainly in the supernatants of A2780 cells. Results also indicated that cell death via autophagy was triggered. Proteomic analysis allowed us to confirm that compound 1 is able to induce a stress response in A2780 cells that is related with its antiproliferative activity and the trigger of apoptosis.
This work was financed by national funds from the Foundation for Science and Technology FCT/MCTES ( UID/Multi/04378/2019 and UID/QUI/00100/2019 ), Portugal, and supported by the Applied Molecular Biosciences Unit- UCIBIO , and by the Centro de Química Estrutural (CQE at IST). AGM is thankful to the CATSUS doctoral program of FCT/MCTES for his PhD fellowship ( SFRH/BD/106006/2014 ). The authors acknowledge the Portuguese NMR Network (IST-UL Centre) for access to the NMR facility and the IST Node of the Portuguese Network of Mass-spectrometry for the ESI-MS measurements. CRR also acknowledges FCT/MCTES through SFRH/BPD/124612/2016. LMDRSM acknowledges FCT/MCTES through PTDC/QEQ-ERQ/1648/2014.
Keywords: 2-D electrophoresis; Antiproliferative activity; Cell death; Ovarian carcinoma; Silver complexes

Antiproliferative activity of heterometallic sodium and potassium-dioxidovanadium(V) polymers - Manas Sutradhar; Alegria, Elisabete C. B. A.; Ferretti, Francesco; Raposo, Luís R.; Guedes da Silva, M. Fátima C.; Baptista, Pedro V; Fernandes, Alexandra R; Pombeiro, Armando J. L. (Journal of Inorganic Biochemistry, 2019)
The syntheses of the heterometallic sodium and potassium-dioxidovanadium 2D polymers, [NaVO2(1κNOO’;2κO”-L)(H2O)]n (1) and [KVO2(1κNOO’;2κO’;3κO”-L)(EtOH)]n (2) (where the κ notation indicates the coordinating atoms of the polydentate ligand L) derived from (3,5-di-tert-butyl-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L) are reported. The polymers were characterized by IR, NMR, elemental analysis and single crystal X-ray diffraction analysis. The antiproliferative potential of 1 and 2 was examined towards four human cancer cell lines (ovarian carcinoma, A2780, colorectal carcinoma, HCT116, prostate carcinoma, PC3 and breast adenocarcinoma, MCF-7cell lines) and normal human fibroblasts. Complex 1 and 2 showed the highest cytotoxic activity against A2780 cell line (IC50 8.2 and 11.3 μM, respectively) with 1 > 2 and an IC50 in the same range as cisplatin (IC50 3.4 μM; obtained in the same experimental conditions) but, interestingly, with no cytotoxicity to healthy human fibroblasts for concentrations up to 75 μM. This high cytotoxicity of 1 in ovarian cancer cells and its low cytotoxicity in healthy cells demonstrates its potential for further biological studies. Our results suggest that both complexes induce ovarian carcinoma cell death via apoptosis and autophagy, but autophagy is the main biological cause of the reduction of viability observed and that ROS (reactive oxygen species) may play an important role in triggering cell death.
info:eu-repo/grantAgreement/FCT/3599-PPCDT/PTDC%2FQEQ-ERQ%2F1648%2F2014/PT# info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UID%2FQUI%2F00100%2F2019/PT# info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UID%2FMulti%2F04378%2F2019/PT# M.S. acknowledges the FCT and IST for a working contract {"}DL/57/2017{"} (Contract no. IST-ID/102/2018).
Keywords: Antiproliferative agent; Aroylhydrazone; Dioxidovanadium(V); X-ray Structure

Targeting cancer resistance via multifunctional gold nanoparticles - Pedro Pedrosa; Corvo, M. Luísa; Ferreira-Silva, Margarida; Pedro Martins; Carvalheiro, Manuela Colla; Costa, Pedro M.; Martins, Carla; Martins, L. M. D. R. S.; Baptista, Pedro V; Fernandes, Alexandra R (International Journal of Molecular Sciences, 2019)
Resistance to chemotherapy is a major problem facing current cancer therapy, which is continuously aiming at the development of new compounds that are capable of tackling tumors that developed resistance toward common chemotherapeutic agents, such as doxorubicin (DOX). Alongside the development of new generations of compounds, nanotechnology-based delivery strategies can significantly improve the in vivo drug stability and target specificity for overcoming drug resistance. In this study, multifunctional gold nanoparticles (AuNP) have been used as a nanoplatform for the targeted delivery of an original anticancer agent, a Zn(II) coordination compound [Zn(DION)2]Cl2 (ZnD), toward better efficacy against DOX-resistant colorectal carcinoma cells (HCT116 DR). Selective delivery of the ZnD nanosystem to cancer cells was achieved by active targeting via cetuximab, NanoZnD, which significantly inhibited cell proliferation and triggered the death of resistant tumor cells, thus improving efficacy. In vivo studies in a colorectal DOX-resistant model corroborated the capability of NanoZnD for the selective targeting of cancer cells, leading to a reduction of tumor growth without systemic toxicity. This approach highlights the potential of gold nanoformulations for the targeting of drug-resistant cancer cells.
info:eu-repo/grantAgreement/FCT/5876/147258/PT# POCI-01-0145-FEDER-007728 SFRH/BD/120030/2016 PD/BD/105734/2014 Pest-OE/UID/DTP/04138/2013
Keywords: Cancer; cancer resistance; Gold nanoparticles; Nanomedicine

Enhanced gas sensing with soft functional materials - S. I. C. J. Palma; Esteves, C; Pádua, AC; Alves, CM; Santos, GMC; Costa, HMA; Dionisio, M.; Gamboa, H.; J. Gruber; Roque, A. C. A. (ISOEN 2019 - 18th International Symposium on Olfaction and Electronic Nose, Proceedings, 2019)
The materials described in this work result from the selfassembly of liquid crystals and ionic liquids into droplets, stabilized within a biopolymeric matrix. These systems are extremely versatile gels, in terms of composition, and offer potential for fine tuning of both structure and function, as each individual component can be varied. Here, the characterization and application of these gels as sensing thin films in gas sensor devices is presented. The unique supramolecular structure of the gels is explored for molecular recognition of volatile organic compounds (VOCs) by employing gels with distinct formulations to yield combinatorial optical and electrical responses used in the distinction and identification of VOCs.

Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug - Santos, Miguel M.; Raposo, Luís R.; Carrera, Gonçalo V. S. M.; Costa, Alexandra; Madalena Dionísio; Baptista, Pedro V; Fernandes, Alexandra R; Branco, Luís C. (Chemmedchem, 2019)
Herein we report the synthesis of novel ionic liquids (ILs) and organic salts by combining ibuprofen as anion with ammonium, imidazolium, or pyridinium cations. The methodology consists of an acid–base reaction of neutral ibuprofen with cation hydroxides, which were previously prepared by anion exchange from the corresponding halide salts with Amberlyst A-26(OH). In comparison with the parent drug, these organic salts display higher solubility in water and biological fluids and a smaller degree of polymorphism, which in some cases was completely eliminated. With the exception of [C 16 Pyr][Ibu] and [N 1,1,2,2OH1 ][Ibu], the prepared salts did not affect the viability of normal human dermal fibroblasts or ovarian carcinoma (A2780) cells. Therefore, these ibuprofen-based ionic liquids may be very promising lead candidates for the development of effective formulations of this drug.
info:eu-repo/grantAgreement/FCT/3599-PPCDT/103664/PT# info:eu-repo/grantAgreement/FCT/5876/147218/PT# info:eu-repo/grantAgreement/FCT/5876/147258/PT# PEst-C/LA0006/2013. PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265 and POCI-01-0145-FEDER-007728.
Keywords: API-ILs; cytotoxicity; ibuprofen; ionic liquids; polymorphism

New lessons from ancient life: marine invertebrates as a source of new drugs - Rodrigo, A. P.; Martins, C.; Tanoeiro, L; Casaca, M; Lopes, A. R.; Parola, A. J.; Matos, A. P.; Baptista, P. V.; Fernandes, A. R.; Costa, P. M. (Annals of Medicine, 2019)
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info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/5876/147218/PT# The Portuguese Foundation for Science and Technology (FCT) funded of project GreenTech (PTDC/MAR-BIO/0113/2014). co-financed by ERDF under the PT2020 Partnership Agreement POCI-01-0145-FEDER-007728 (UCIBIO) and POCI-010145-FEDER -007265 (LAQV). FCT is also acknowledged for the grants SFRH/BD/109462/2015 to A.P.R., SFRH/BD/120030/2016 to C.M. and IF/00265/2015 to P.M.C.; Joint Congress of 3rd International Congress of CiiEM Research and Innovation in Human and Health Sciences and the 3rd World Congress of the UNESCO Chair for Teaching and Research in Digital Anatomy Paris Descartes ; Conference date: 20-06-2018 Through 22-06-2018

Non-destructive microstructural analysis by electrical conductivity: Comparison with hardness measurements in different materials - Sorger, Gonçalo L.; Oliveira, J.P.; Inácio, Patrick L.; Enzinger, Norbert; Pedro Vilaça; Miranda, R.M.; Telmo G. Santos (Journal of Materials Science & Technology, 2019)
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Antibody modified gold nanoparticles for fast colorimetric screening of rheumatoid arthritis - Bruno Veigas; Matias, Ana; Calmeiro, Tomás; Elvira Fortunato; Fernandes, Alexandra R; Baptista, Pedro Viana (Analyst, 2019)
Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic joint inflammation and one of the main causes of chronic disability worldwide with high prevalence in the ageing population. RA is characterized by autoantibody production, synovial inflammation and bone destruction, and the most accepted biomarker is rheumatoid factor (RF) autoantibodies. In this work, we developed a low-cost approach for the detection and quantification of the RF marker. This colorimetric immunosensor is based on gold nanoprobe crosslinking that results in extensive aggregation in the presence of the pentameric IgM RF. Aggregation of the nanoconjugates yields a color change from red to purple that can be easily observed by the naked eye. The interaction between nanoconjugates and the specific target was confirmed via dynamic light scattering (DLS), Raman spectroscopy and atomic force microscopy (AFM) imaging. This conceptual system shows a LOD of 4.15 UA mL-1 IgM RF (clinical threshold is set for 20 IU mL-1). The one-step biosensor strategy herein proposed is much faster than conventional detection techniques, without the need for secondary antibodies, additional complex washing or signal amplification protocols. To the best of our knowledge this is the first report on target induced aggregation of gold nanoprobes for quantitative colorimetric autoantibody detection.
info:eu-repo/grantAgreement/FCT/5876/147258/PT# POCI-01-0145-FEDER-007728. Project INNO INDIGO 2015 - RA Detect: One Platform-Multiple biomarker detection of Rheumatoid Arthritis (https://radetect.eu/). SFRH/BPD/124311/2016. Sem PDF conforme despacho.

Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product - Constantina Kourmentza; Araújo, Diana; Chantal Sevrin; Catarina Roma-Rodriques; Ferreira, Joana Lia; Freitas, Filomena; Dionisio, Madalena; Baptista, Pedro V; Fernandes, Alexandra R; Christian Grandfils; Reis, Maria A. M. (Bioresource Technology, 2019)
While screening for polyhydroxyalkanoate (PHA) producing strains, using glycerol rich by-product as carbon source, it was observed that extracellular polymers were also secreted into the culture broth. The scope of this study was to characterize both intracellular and extracellular polymers, produced by Pseudomonas putida NRRL B-14875 and Pseudomonas chlororaphis DSM 50083, mostly focusing on those novel extracellular polymers. It was found that they fall into the class of bioemulsifiers (BE), as they showed excellent emulsion stability against different hydrocarbons/oils at various pH conditions, temperature and salinity concentrations. Cytotoxicity tests revealed that BE produced by P. chlororaphis inhibited the growth of highly pigmented human melanoma cells (MNT-1) by 50% at concentrations between 150 and 200 μg/mL, while no effect was observed on normal skin primary keratinocytes and melanocytes. This is the first study reporting mcl-PHA production by P. putida NRRL B-14785 and bioemulsifier production from both P. putida and P. chlororaphis strains.
info:eu-repo/grantAgreement/EC/FP7/625774/EU# European Commission FP7-PEOPLE-2013-IEF-Marie Curie. Sem PDF conforme despacho.
Keywords: Bioemulsifiers; Crude glycerol; cytotoxicity; Polyhydroxyalkanoates; Pseudomonas chlororaphis; Pseudomonas putida

Foreword - Roque, A. C. A.; Fred, A; Gamboa, H. (BIODEVICES 2019 - 12th International Conference on Biomedical Electronics and Devices, Proceedings; Part of 12th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2019, 2019)

Tofacitinib Synthesis - An Asymmetric Challenge - Carvalho, Luisa C. R.; Lourenco, Ana; Ferreira, Luisa Maria; Branco, Paula Serio (EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, 2019)
Tofacitinib is a Janus activated kinase (JAK) inhibitor approved for the treatment of rheumatoid arthritis and active psoriatic arthritis. Its synthesis normally involves long synthetic sequences due to the chirality associated to the piperidine ring. This review is a comprehensive analysis of the different synthetic methods used to prepare this active pharmaceutical ingredient (API), covering the related journal and patent literature.
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Targeting Tumor Microenvironment for Cancer Therapy - Catarina Roma-Rodrigues; Rita Mendes; Baptista, Pedro V; Fernandes, Alexandra R (International Journal of Molecular Sciences, 2019)
Cancer development is highly associated to the physiological state of the tumor microenvironment (TME). Despite the existing heterogeneity of tumors from the same or from different anatomical locations, common features can be found in the TME maturation of epithelial-derived tumors. Genetic alterations in tumor cells result in hyperplasia, uncontrolled growth, resistance to apoptosis, and metabolic shift towards anaerobic glycolysis (Warburg effect). These events create hypoxia, oxidative stress and acidosis within the TME triggering an adjustment of the extracellular matrix (ECM), a response from neighbor stromal cells (e.g., fibroblasts) and immune cells (lymphocytes and macrophages), inducing angiogenesis and, ultimately, resulting in metastasis. Exosomes secreted by TME cells are central players in all these events. The TME profile is preponderant on prognosis and impacts efficacy of anti-cancer therapies. Hence, a big effort has been made to develop new therapeutic strategies towards a more efficient targeting of TME. These efforts focus on: (i) therapeutic strategies targeting TME components, extending from conventional therapeutics, to combined therapies and nanomedicines; and (ii) the development of models that accurately resemble the TME for bench investigations, including tumor-tissue explants, {"}tumor on a chip{"} or multicellular tumor-spheroids.
This work was funded by the Applied Molecular Biosciences Unit-UCIBIO, which is financed by national funds from FCT/MCTES (UID/Multi/04378/2019) and by Fundacao para a Ciencia e Tecnologia, Post-Doc grant SFRH/BPD/124612/2016 to C.R.-R.
Keywords: cancer therapy; models for tumor microenvironment study; nanomedicines; tumor development; Tumor microenvironment

GLUT1 and GLUT3 involvement in anthocyanin gastric transport- Nanobased targeted approach - Oliveira, Hélder; Catarina Roma-Rodrigues; Santos, Ana; Bruno Veigas; Brás, Natércia; Faria, Ana; Conceição Calhau; {de Freitas}, Victor; Baptista, Pedro V; Mateus, Nuno; Fernandes, Alexandra R; Fernandes, Iva (Scientific Reports, 2019)
Anthocyanins may protect against a myriad of human diseases. However few studies have been conducted to evaluate their bioavailability so their absorption mechanism remains unclear. This study aimed to evaluate the role of two glucose transporters (GLUT1 and GLUT3) in anthocyanins absorption in the human gastric epithelial cells (MKN-28) by using gold nanoparticles to silence these transporters. Anthocyanins were purified from purple fleshed sweet potatoes and grape skin. Silencing of GLUT1 and/or GLUT3 mRNA was performed by adding AuNP@GLUT1 and/or AuNP@GLUT3 to MKN-28 cells. Downregulation of mRNA expression occurred concomitantly with the reduction in protein expression. Malvidin-3-O-glucoside (Mv3glc) transport was reduced in the presence of either AuNP@GLUT1 and AuNP@GLUT3, and when both transporters were blocked simultaneously. Peonidin-3-(6′-hydroxybenzoyl)-sophoroside-5-glucoside (Pn3HBsoph5glc) and Peonidin-3-(6′-hydroxybenzoyl-6″-caffeoyl)-sophoroside-5-glucoside (Pn3HBCsoph5glc) were assayed to verify the effect of the sugar moiety esterification at glucose B in transporter binding. Both pigments were transported with a lower transport efficiency compared to Mv3glc, probably due to steric hindrance of the more complex structures. Interestingly, for Pn3HBCsoph5glc although the only free glucose is at C5 and the inhibitory effect of the nanoparticles was also observed, reinforcing the importance of glucose on the transport regardless of its position or substitution pattern. The results support the involvement of GLUT1 and GLUT3 in the gastric absorption of anthocyanins.
info:eu-repo/grantAgreement/FCT/5876/147218/PT# info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBPD%2F86173%2F2012/PT# PTDC/AGR-TEC/3078/2014 POCI-01-0145-FEDER-007728 grant (IF/01355/2014) PD/BD/106062/2015 attributed by the Doctoral Programme M2B-PhD. Post-Doc grant from FCT (SFRH/BPD/124612/2016)

In Situ Structural Characterization of Functionally Graded Ni–Ti Shape Memory Alloy During Tensile Loading - Braz Fernandes, Francisco M.; Camacho, Edgar; Rodrigues, Patrícia F.; Inácio, Patrick; Telmo G. Santos; Schell, Norbert (Shape Memory and Superelasticity, 2019)
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Paper-Based SERS Platform for One-Step Screening of Tetracycline in Milk - Marques, Ana; Bruno Veigas; Araújo, Andreia; Pagará, Beatriz; Baptista, Pedro Viana; Hugo Águas; Rodrigo Martins; Elvira Fortunato (Scientific Reports, 2019)
Throughout the last decade, the expansion of food testing has been gradually moving towards ordinary high throughput screening methods performed on-site. The demand for point-of-care testing, able to distinguish molecular signatures with high accuracy, sensitivity and specificity has been significantly increasing. This new requirement relies on the on-site detection and monitorization of molecular signatures suitable for the surveillance of food production and processing. The widespread use of antibiotics has contributed to disease control of livestock but has also created problems for the dairy industry and consumers. Its therapeutic and subtherapeutic use has increased the risk of contamination in milk in enough concentrations to cause economic losses to the dairy industry and have a health impact in highly sensitive individuals. This study focuses on the development of a simple Surface-Enhanced Raman Spectroscopy (SERS) method for fast high throughput screening of tetracycline (TET) in milk. For this, we integrate a paper-based low-cost, fully recyclable and highly stable SERS platform, with a minimal sample preparation protocol. A two-microliter sample of milk solutions spiked with TET (from 0.01 to 1000 ppm) is dried on a silver nanoparticle coated cardboard substrate and measured via a Raman spectrophotometer. The SERS substrate showed to be extremely stable with a shelf life of several months. A global spectrum principal component analysis approach was used to test all the detected vibrational modes and their correlation with TET concentration. Peak intensity ratios (455 cm−1/1280 cm−1 and 874 cm−1/1397 cm−1) were found to be correlated with TET concentrations in milk, achieving a sensitivity as low as 0.1 ppm. Results indicate that this SERS method combined with portable Raman spectrometer is a potential tool that can be used on-site for the monitoring of TET residues and other antibiotics.
info:eu-repo/grantAgreement/FCT/5876/147258/PT# PTDC/CTM-NAN/2912/2014. PTDC/AAG-TEC/5400/2014. POCI-01-0145-FEDER-016637. POCI-01-0145-FEDER-007688. UID/CTM/50025/2019. FCT/MCTES SFRH/BD/115173/2016 and SFRH/BPD/124311/2016 .

Nanotheranostics Targeting the Tumor Microenvironment - Catarina Roma-Rodrigues; Pombo, Inês; Raposo, Luís; Pedro Pedrosa; Fernandes, Alexandra R; Baptista, Pedro V (Frontiers in Bioengineering and Biotechnology, 2019)
Cancer is considered the most aggressive malignancy to humans, and definitely the major cause of death worldwide. Despite the different and heterogenous presentation of the disease, there are pivotal cell elements involved in proliferation, differentiation, and immortalization, and ultimately the capability to evade treatment strategies. This is of utmost relevance when we are just beginning to grasp the complexity of the tumor environment and the molecular {"}evolution{"} within. The tumor micro-environment (TME) is thought to provide for differentiation niches for clonal development that results in tremendous cancer heterogeneity. To date, conventional cancer therapeutic strategies against cancer are failing to tackle the intricate interplay of actors within the TME. Nanomedicine has been proposing innovative strategies to tackle this TME and the cancer cells that simultaneously provide for biodistribution and/or assessment of action. These nanotheranostics systems are usually multi-functional nanosystems capable to carry and deliver active cargo to the site of interest and provide diagnostics capability, enabling early detection, and destruction of cancer cells in a more selective way. Some of the most promising multifunctional nanosystems are based on gold nanoparticles, whose physic-chemical properties have prompt for the development of multifunctional, responsive nanomedicines suitable for combinatory therapy and theranostics. Herein, we shall focus on the recent developments relying on the properties of gold nanoparticles as the basis for nanotheranostics systems against the heterogeneity within the TME.
UID/Multi/04378/2019 SFRH/BPD/124612/2016 PD/BD/105734/2014
Keywords: cancer therapy; diagnostic; Gold nanoparticles; Nanomedicine; nanotheranostics; Tumor microenvironment

Recovery of Cr(III) by using chars from the co-gasification of agriculture and forestry wastes - Godinho, Delfina; Nogueira, Miguel; Bernardo, Maria; Diogo Dias; Nuno Lapa; Fonseca, Isabel; Filomena Pinto (Environmental Science and Pollution Research, 2019)
The aim of the present work was to assess the efficiency of biochars obtained from the co-gasification of blends of rice huskþinspace}+þinspace}corn cob (biochar 50CC) and rice huskþinspace}+þinspace}eucalyptus stumps (biochar 50ES), as potential renewable low-cost adsorbents for Cr(III) recovery from wastewaters. The two gasification biochars presented a weak porous structure (ABETþinspace}=þinspace}63–144 m2 g−1), but a strong alkaline character, promoted by a high content of mineral matter (59.8{%} w/w of ashes for 50CC biochar and 81.9{%} w/w for 50ES biochar). The biochars were used for Cr(III) recovery from synthetic solutions by varying the initial pH value (3, 4, and 5), liquid/solid (L/S) ratio (100–500 mL g−1), contact time (1–120 h), and initial Cr(III) concentration (10–150 mg L−1). High Cr(III) removal percentages (around 100{%}) were obtained for both biochars, due to Cr precipitation, at low L/S ratios (100 and 200 mL g−1), for the initial pH 5 and initial Cr concentration of 50 mg L−1. Under the experimental conditions in which other removal mechanisms rather than precipitation occurred, a higher removal percentage (49.9{%}) and the highest uptake capacity (6.87 mg g−1) were registered for 50CC biochar. In the equilibrium, 50ES biochar presented a Cr(III) removal percentage of 27{%} with a maximum uptake capacity of 2.58 mg g−1. The better performance on Cr(III) recovery for the biochar 50CC was attributed to its better textural properties, as well as its higher cation exchange capacity.
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N-Heterocyclic Olefin Catalysis for the Ring Opening of Cyclic Amidine Compounds: A Pathway to the Synthesis of c-Caprolactamand -Lactam-Derived Amines - Peixoto, Daniela; Malta, Gabriela; Cruz, Hugo; Barroso, Sonia; Carvalho, Ana Luisa; Ferreira, Luisa M.; Branco, Paula S. (JOURNAL OF ORGANIC CHEMISTRY, 2019)
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Enhancement of water solubility of poorly water-soluble drugs by new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids - Jesus, Ana R.; Soromenho, Mário R.C.; Raposo, Luís R.; Esperança, José M. S. S.; Baptista, Pedro V; Fernandes, Alexandra R; Reis, Patrícia M. (European Journal of Pharmaceutics and Biopharmaceutics, 2019)
The major challenge of the pharmaceutical industry is to find potential solvents for poorly water-soluble drug molecules. Ionic liquids (ILs) have attracted this industry as (co-) solvents due to their unique physicochemical and biological properties. Herein, a straightforward approach for the enhancement of water solubility of paracetamol and sodium diclofenac is presented, using new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids as co-solvents (0.2 - 1 mol%). These new ionic liquids were able to increase water solubility of these drugs up to four times higher than in pure water or in an inorganic salt solution. In the presence of these ILs the drugs lipophilicity (log Kow) was not significantly changed for paracetamol, but for sodium diclofenac it was possible to decrease significantly its lipophilicity. Concerning cytotoxicity in human dermal fibroblasts it was observed that ILs did not show a significant toxicity, and were able to improve cell viability compared with the respective precursors.
IF/00355/2012 IF/00621/2015 IF/00621/2015 UID/QUI/50006/2019 POCI-01-0145-FEDER-007265 UID/Multi/04378/2019 POCI-01-0145-FEDER-007728 Sem PDF conforme despacho.

Structural aspects of a trimetallic Cu II derivative: cytotoxicity and anti-proliferative activity on human cancer cell lines - Kuheli Das; Amitabha Datta; Chiara Massera; Catarina Roma-Rodrigues; Mariana Barroso; Baptista, Pedro V; Fernandes, Alexandra R (Journal of Coordination Chemistry, 2019)
A trimetallic Cu II derivative, [Cu 3 (L) 2 (CF 3 COO) 2 ] (1) (where H 2 L = N,N′-bis(salicylidene)-1,3-propanediamine), was prepared and characterized. In 1, the two terminal Cu II ions are linked to the central Cu II by trifluoroacetato and doubly bridging phenoxido. Both the square-pyramidal and octahedral geometries are observed among two different Cu II centers in the linear arrangement of the trimetallic unit. Compound 1 is characterized by IR and UV-Vis spectra. Compound 1 has high cytotoxic activity in breast adenocarcinoma (MCF-7), colorectal carcinoma (HCT116) and particularly, in ovarian carcinoma (A2780) cell line compared to a lung adenocarcinoma cell line. The IC 50 in A2780 cells is 25 times lower than the respective value for normal human primary fibroblasts demonstrating 1 has higher cytotoxicity towards cancer cells. Additionally, combination of DOX with 1 induces a higher loss of HCT116 cell viability compared with each drug alone.
info:eu-repo/grantAgreement/FCT/5876/147258/PT# co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728).
Keywords: Cancer cell lines; copper(II); cytotoxicity; DOX; trimetallic

Front Contact Light Trapping Structures by Design for Maximum Efficiency Enhancement of Thin Film Solar Cells - Mendes, Manuel J. (28th International Conference on Amorphous and Nano-crystalline Semiconductors (ICANS), 2019)

Ultra-Thin Perovskite/c-Silicon Four-Terminal Tandems: Interlayer and Intermediate Contacts Optimization - Mendes, Manuel J. (28th International Conference on Amorphous and Nano-crystalline Semiconductors (ICANS), 2019)

Enhancement of the structural behaviour of flat slabs under cyclic and seismic actions through the rational use of high performance fibre reinforced concrete - Sandra Nunes (CONSTRUCT DAY 2019, 2019)

Spotting plants’ microfilament morphologies and nanostructures - Almeida, Ana P.; Canejo, João; Mur, Urban; Čopar, Simon; Almeida, Pedro L; Žumer, Slobodan; Godinho, Maria Helena (Proceedings of the National Academy of Sciences, 2019)
Microfibers existing in the tracheary systems of plants are crucial for the plants to survive. These microfilaments are curled up, forming left-handed helices that make the contour of tubes responsible for the transport of water and nutrients from the roots to the leaves. The microfilaments present mechanical properties that vary from plant to plant despite having similar polygonal-helical shapes and cellulose skeletons. Here we show that the surface morphology of the microfilaments, sensed by nematic liquid crystal droplets, is at the origin of entanglements, which are responsible for the mechanical behavior of microfilaments. This work introduces routes for the accurate characterization of plants’ microfilaments and to produce bioinspired textiles.The tracheary system of plant leaves is composed of a cellulose skeleton with diverse hierarchical structures. It is built of polygonally bent helical microfilaments of cellulose-based nanostructures coated by different layers, which provide them high compression resistance, elasticity, and roughness. Their function includes the transport of water and nutrients from the roots to the leaves. Unveiling details about local interactions of tracheary elements with surrounding material, which varies between plants due to adaptation to different environments, is crucial for understanding ascending fluid transport and for tracheary mechanical strength relevant to potential applications. Here we show that plant tracheary microfilaments, collected from Agapanthus africanus and Ornithogalum thyrsoides leaves, have different surface morphologies, revealed by nematic liquid crystal droplets. This results in diverse interactions among microfilaments and with the environment; the differences translate to diverse mechanical properties of entangled microfilaments and their potential applications. The presented study also introduces routes for accurate characterization of plants’ microfilaments.
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Antibody modified gold nanoparticles for fast colorimetric screening of rheumatoid arthritis - B. Veigas; A. Matias; Calmeiro, T; E. Fortunato; Fernandes, A. R.; P.V. Baptista (Analyst, 2019)
Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic joint inflammation and one of the main causes of chronic disability worldwide with high prevalence in the ageing population. RA is characterized by autoantibody production, synovial inflammation and bone destruction, and the most accepted biomarker is rheumatoid factor (RF) autoantibodies. In this work, we developed a low-cost approach for the detection and quantification of the RF marker. This colorimetric immunosensor is based on gold nanoprobe crosslinking that results in extensive aggregation in the presence of the pentameric IgM RF. Aggregation of the nanoconjugates yields a color change from red to purple that can be easily observed by the naked eye. The interaction between nanoconjugates and the specific target was confirmed via dynamic light scattering (DLS), Raman spectroscopy and atomic force microscopy (AFM) imaging. This conceptual system shows a LOD of 4.15 UA mL(-1) IgM RF (clinical threshold is set for 20 IU mL(-1)). The one-step biosensor strategy herein proposed is much faster than conventional detection techniques, without the need for secondary antibodies, additional complex washing or signal amplification protocols. To the best of our knowledge this is the first report on target induced aggregation of gold nanoprobes for quantitative colorimetric autoantibody detection.
Veigas, BrunoMatias, Ana Calmeiro, Tomas Fortunato, Elvira Fernandes, Alexandra R Baptista, Pedro Viana eng England Analyst. 2019 Jun 7;144(11):3613-3619. doi: 10.1039/c9an00319c. Epub 2019 May 9.
Keywords: Arthritis, Rheumatoid/*diagnosis/immunology; Biomarkers; Biosensing Techniques/methods; Colorimetry/methods; Gold/*chemistry; Humans; Immunoglobulin Fc Fragments/immunology; Immunoglobulin G/immunology; Immunoglobulin M/*blood/immunology; Limit of Detection; Metal Nanoparticles/*chemistry; Particle Size; Rheumatoid Factor/*blood/immunology

Antiproliferative activity of heterometallic sodium and potassium-dioxidovanadium(V) polymers - Sutradhar, M.; Alegria, E.C.B.A.; Ferretti, F.; Raposo, L. R.; Guedes da Silva, M.F.C.; P.V. Baptista; Fernandes, A. R.; Pombeiro, A. J. L. (J Inorg Biochem, 2019)
The syntheses of the heterometallic sodium and potassium-dioxidovanadium 2D polymers, [NaVO2(1kappaNOO';2kappaO"-L)(H2O)]n(1) and [KVO2(1kappaNOO';2kappaO';3kappaO"-L)(EtOH)]n(2) (where the kappa notation indicates the coordinating atoms of the polydentate ligand L) derived from (3,5-di-tert-butyl-2-hydroxybenzylidene)-2-hydroxybenzohydrazide (H2L) are reported. The polymers were characterized by IR, NMR, elemental analysis and single crystal X-ray diffraction analysis. The antiproliferative potential of 1 and 2 was examined towards four human cancer cell lines (ovarian carcinoma, A2780, colorectal carcinoma, HCT116, prostate carcinoma, PC3 and breast adenocarcinoma, MCF-7cell lines) and normal human fibroblasts. Complex 1 and 2 showed the highest cytotoxic activity against A2780 cell line (IC50 8.2 and 11.3muM, respectively) with 1>2 and an IC50 in the same range as cisplatin (IC50 3.4muM; obtained in the same experimental conditions) but, interestingly, with no cytotoxicity to healthy human fibroblasts for concentrations up to 75muM. This high cytotoxicity of 1 in ovarian cancer cells and its low cytotoxicity in healthy cells demonstrates its potential for further biological studies. Our results suggest that both complexes induce ovarian carcinoma cell death via apoptosis and autophagy, but autophagy is the main biological cause of the reduction of viability observed and that ROS (reactive oxygen species) may play an important role in triggering cell death.
Sutradhar, ManasAlegria, Elisabete C B A Ferretti, Francesco Raposo, Luis R Guedes da Silva, M Fatima C Baptista, Pedro V Fernandes, Alexandra R Pombeiro, Armando J L eng Research Support, Non-U.S. Gov't J Inorg Biochem. 2019 Nov;200:110811. doi: 10.1016/j.jinorgbio.2019.110811. Epub 2019 Aug 27.
Keywords: *Antineoplastic Agents/chemistry/pharmacology; *Antiproliferative agent; *Aroylhydrazone; *Dioxidovanadium(V); *Potassium/chemistry/pharmacology; *Sodium/chemistry/pharmacology; *Vanadium Compounds/chemistry/pharmacology; *X-ray structure; Cell Proliferation/*drug effects; HCT116 Cells; Humans; MCF-7 Cells; Neoplasms/*drug therapy/metabolism/pathology; PC-3 Cells

Backbone assignment of cytochrome PccH, a crucial protein for microbial electrosynthesis in Geobacter sulfurreducens - Liliana R. Teixeira; Portela, Pilar C.; Leonor Morgado; Pantoja-Uceda, David; Bruix, Marta; Salgueiro, , Carlos A. (Biomol NMR Assign, 2019)
Microbial electrosynthesis is an emerging green technology that explores the capability of a particular group of microorganisms to drive their metabolism toward the production of hydrogen or value-added chemicals from electrons supplied by electrode surfaces. The cytochrome PccH showed the largest increase in transcription when electrons are supplied to Geobacter sulfurreducens biofilms. Gene knock-out experiments have shown that the electron transfer toward G. sulfurreducens cells was completely inhibited by the deletion of the gene encoding for cytochrome PccH. This identifies a crucial role for this protein in G. sulfurreducens microbial electrosynthesis mechanisms, which are currently unknown. In this work, we present the backbone (1H, 13C and 15N) and heme assignment for PccH in the oxidized state. The data obtained paves the way to identify and structurally map the molecular interaction regions between the cytochrome PccH and its physiological redox partners.
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Biofilm development and computational screening for new putative inhibitors of a homolog of the regulatory protein BrpA in Streptococcus dysgalactiae subsp. dysgalactiae - Alves-Barroco, C.; Roma-Rodrigues, C.; Balasubramanian, N.; Guimaraes, M. A.; Ferreira-Carvalho, B. T.; J Muthukumaran; Nunes, D.; E. Fortunato; R. Martins; Santos-Silva, T.; Figueiredo, A. M. S.; Fernandes, A. R.; et al. (Int J Med Microbiol, 2019)
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry. Adherence and biofilm production are important factors in streptoccocal pathogenesis. We have previously described the adhesion and internalization of SDSD isolates in human cells and now we describe the biofilm production capability of this bacterium. In this work we integrated microbiology, imaging and computational methods to evaluate the biofilm production capability of SDSD isolates; to assess the presence of biofilm regulatory protein BrpA homolog in the biofilm producers; and to predict a structural model of BrpA-like protein and its binding to putative inhibitors. Our results show that SDSD isolates form biofilms on abiotic surface such as glass (hydrophilic) and polystyrene (hydrophobic), with the strongest biofilm formation observed in glass. This ability was mainly associated with a proteinaceous extracellular matrix, confirmed by the dispersion of the biofilms after proteinase K and trypsin treatment. The biofilm formation in SDSD isolates was also confirmed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Under SEM observation, VSD16 isolate formed cell aggregates during biofilm growth while VSD9 and VSD10 formed smooth and filmy layers. We show that brpA-like gene is present and expressed in SDSD biofilm-producing isolates and its expression levels correlated with the biofilm production capability, being more expressed in the late exponential phase of planktonic growth compared to biofilm growth. Fisetin, a known biofilm inhibitor and a putative BrpA binding molecule, dramatically inhibited biofilm formation by the SDSD isolates but did not affect planktonic growth, at the tested concentrations. Homology modeling was used to predict the 3D structure of BrpA-like protein. Using high throughput virtual screening and molecular docking, we selected five ligand molecules with strong binding affinity to the hydrophobic cleft of the protein, making them potential inhibitor candidates of the SDSD BrpA-like protein. These results warrant further investigations for developing novel strategies for SDSD anti-biofilm therapy.
Alves-Barroco, CinthiaRoma-Rodrigues, Catarina Balasubramanian, Natesan Guimaraes, Marcia Aparecida Ferreira-Carvalho, Bernadete T Muthukumaran, Jayaraman Nunes, Daniela Fortunato, Elvira Martins, Rodrigo Santos-Silva, Teresa Figueiredo, Agnes M S Fernandes, Alexandra R Santos-Sanches, Ilda eng Germany Int J Med Microbiol. 2019 May - Jun;309(3-4):169-181. doi: 10.1016/j.ijmm.2019.02.001. Epub 2019 Feb 19.
Keywords: Animals; Anti-Bacterial Agents/*chemistry/pharmacology; Bacterial Proteins/*antagonists & inhibitors/chemistry/genetics/metabolism; Biofilm; Biofilm regulatory protein; Biofilms/drug effects/*growth & development; BrpA inhibitors; Extracellular Polymeric Substance Matrix/chemistry/metabolism/ultrastructure; Female; Flavonoids/chemistry/pharmacology; Gene Expression; Gene Expression Regulation, Bacterial; Molecular docking; Molecular Docking Simulation; Molecular Structure; Protein Binding; Protein Conformation; Streptococcal Infections/microbiology; Streptococcus dysgalactiae subsp. dysgalactiae; Streptococcus/drug effects/genetics/metabolism/*physiology

Copper(ii) complexes with 2,2':6',2''-terpyridine, 2,6-di(thiazol-2-yl)pyridine and 2,6-di(pyrazin-2-yl)pyridine substituted with quinolines. Synthesis, structure, antiproliferative activity, and catalytic activity in the oxidation of alkanes and alcohols - Choroba, K.; Machura, B.; Kula, S.; Raposo, L. R.; Fernandes, A. R.; Kruszynski, R.; Erfurt, K.; Shul'pina, L. S.; Kozlov, Y. N.; Shul'pin, G. B. (Dalton Trans, 2019)
A series of 2,2':6',2''-terpyridine (terpy), 2,6-di(thiazol-2-yl)pyridine (dtpy) and 2,6-di(pyrazin-2-yl)pyridine (dppy) derivatives with n-quinolyl substituents (n = 2 and 4) was used to synthesize five-coordinate complexes [CuCl2(n-quinolyl-terpy)] (1-2), [CuCl2(n-quinolyl-dtpy)] (3-4) and [CuCl2(n-quinolyl-dppy)] (5-6), respectively. The main emphasis of the research was to investigate the impact of the triimine skeleton (terpy, dtpy and dppy) and n-quinolyl pendant substituent on the antiproliferative and catalytic properties of 1-6. The obtained Cu(ii) compounds were studied as antiproliferative agents against human colorectal (HCT116) and ovarian (A2780) carcinoma, and they were used as catalysts for the oxidation of alkanes and alcohols with peroxides under mild conditions. The kinetic characteristics of the oxidizing species generated by the catalytic system Cu(ii) complex-H2O2 in CH3CN were obtained from the dependence of the alkane oxidation rate on its initial concentration. A model of competitive interaction of hydroxyl radicals with CH3CN and RH in the catalyst cavity has been proposed which is based on the simultaneous study of kinetics and selectivity in alkane oxidations.
Choroba, KatarzynaMachura, Barbara Kula, Slawomir Raposo, Luis R Fernandes, Alexandra R Kruszynski, Rafal Erfurt, Karol Shul'pina, Lidia S Kozlov, Yuriy N Shul'pin, Georgiy B eng England Dalton Trans. 2019 Sep 7;48(33):12656-12673. doi: 10.1039/c9dt01922g. Epub 2019 Aug 6.

Counteracting the effect of leukemia exosomes by antiangiogenic gold nanoparticles - Roma-Rodrigues, C.; Fernandes, A. R.; P.V. Baptista (Int J Nanomedicine, 2019)
Purpose: Progression of chronic myeloid leukemia (CML) is frequently associated with increased angiogenesis at the bone marrow mediated by exosomes. The capability of gold nanoparticles (AuNPs) functionalized with antiangiogenic peptides to hinder the formation of new blood vessels has been demonstrated in a chorioallantoic membrane (CAM) model. Methods: Exosomes of K562 CML cell line were isolated and their angiogenic effect assessed in a CAM model. AuNPs functionalized with antiangiogenic peptides were used to block the angiogenic effect of CML-derived exosomes, assessed by evaluation of expression levels of key modulators involved in angiogenic pathways - VEGFA, VEGFR1 (also known as FLT1) and IL8. Results: Exosomes isolated from K562 cells promoted the doubling of newly formed vessels associated with the increase of VEGFR1 expression. This is a concentration and time-dependent effect. The AuNPs functionalized with antiangiogenic peptides were capable to block the angiogenic effect by modulating VEGFR1 associated pathway. Conclusion: Exosomes derived from blast cells are capable to trigger (neo)-angiogenesis, a key factor for the progression and spreading of cancer, in particular in CML. AuNPs functionalized with specific antiangiogenic peptides are capable to block the effect of the exosomes produced by malignant cells via modulation of the intrinsic VEGFR pathway. Together, these data highlight the potential of nanomedicine-based strategies against cancer proliferation.
Roma-Rodrigues, CatarinaFernandes, Alexandra R Baptista, Pedro V eng New Zealand Int J Nanomedicine. 2019 Aug 26;14:6843-6854. doi: 10.2147/IJN.S215711. eCollection 2019.
Keywords: angiogenesis; Angiogenesis Inhibitors/chemistry/*pharmacology; Animals; Chick Embryo; chorioallantoic membrane; Chorioallantoic Membrane/drug effects; chronic myeloid leukemia; Exosomes; Exosomes/metabolism/*pathology; Gold nanoparticles; Gold/chemistry/*pharmacology; Humans; Interleukin-8/metabolism; K562 Cells/metabolism; Metal Nanoparticles/chemistry/*therapeutic use; Neovascularization, Pathologic/*drug therapy/metabolism; Vascular Endothelial Growth Factor A/metabolism; Vascular Endothelial Growth Factor Receptor-1/metabolism

Enhancement of water solubility of poorly water-soluble drugs by new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids - Jesus, A. R.; Soromenho, M. R. C.; Raposo, L. R.; Esperanca, Jmss; P.V. Baptista; Fernandes, A. R.; Reis, P. M. (Eur J Pharm Biopharm, 2019)
The major challenge of the pharmaceutical industry is to find potential solvents for poorly water-soluble drug molecules. Ionic liquids (ILs) have attracted this industry as (co-) solvents due to their unique physicochemical and biological properties. Herein, a straightforward approach for the enhancement of the water solubility of paracetamol and sodium diclofenac is presented, using new biocompatible N-acetyl amino acid N-alkyl cholinium-based ionic liquids as co-solvents (0.2-1mol%). These new ionic liquids were able to increase the water solubility of these drugs up to four times that in pure water or in an inorganic salt solution. In the presence of these ILs, the drugs lipophilicity (log P was not significantly changed for paracetamol, but for sodium diclofenac it was possible to decrease significantly its lipophilicity. Concerning cytotoxicity in human dermal fibroblasts it was observed that ILs did not show a significant toxicity, and were able to improve cell viability compared with the respective precursors.
Jesus, Ana RSoromenho, Mario R C Raposo, Luis R Esperanca, Jose M S S Baptista, Pedro V Fernandes, Alexandra R Reis, Patricia M eng Comparative Study Netherlands Eur J Pharm Biopharm. 2019 Apr;137:227-232. doi: 10.1016/j.ejpb.2019.03.004. Epub 2019 Mar 2.
Keywords: Acetaminophen/*chemistry/toxicity; Amino acids; Amino Acids/*chemistry; Bioavailability; Cell Survival/drug effects; Cells, Cultured; Chemistry, Pharmaceutical/methods; Choline/chemistry; cytotoxicity; Diclofenac/*chemistry/toxicity; Drug delivery; Fibroblasts/*drug effects/metabolism; Humans; Hydrophobic and Hydrophilic Interactions; ionic liquids; Ionic Liquids/chemistry; Solubility; Solvents/chemistry; Water/chemistry

First heterobimetallic Cu(i)–dppf complexes designed for anticancer applications: synthesis, structural characterization and cytotoxicity - Bravo, Catarina; Robalo, M. Paula; Marques, Fernanda; Alexandra R. Fernandes; Sequeira, Diogo A.; M. Piedade, M. Fátima; Garcia, M. Helena; de Brito, Maria J. Villa; Morais, Tânia S. (New Journal of Chemistry, 2019)
A new family of eight heterobimetallic Cu(i)–dppf complexes of general formula [Cu(dppf)L][BF4] with dppf = 1,1′-bis(diphenylphosphino)ferrocene and L representing N,N-, N,O- and N,S-heteroaromatic bidentate ligands have been synthesized and fully characterized by classical analytical, spectroscopic and electrochemical methods. The single crystal structures of [Cu(dppf)(pBI)][BF4] (6), [Cu(dppf)(dpytz)][BF4] (7) and [Cu(dppf)(5-Aphen)][BF4] (8) complexes (where pBI = 2-(2-pyridyl)benzimidazole, dpytz = 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine and 5-Aphen = 1,10-phenanthrolin-5-amine) were determined by X-ray diffraction studies. Cytotoxicity of all complexes was evaluated in two human breast adenocarcinoma cell lines (MCF7 and MDAMB231). All the complexes exhibit high cytotoxicity against both human breast cancer cells with IC50 values far lower than those found for the antitumor drug cisplatin in the same cell lines. The IC50 values on primary healthy fibroblasts are of the same order of magnitude as those found for the tumoral cells.
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GLUT1 and GLUT3 involvement in anthocyanin gastric transport- Nanobased targeted approach - Oliveira, H.; Roma-Rodrigues, C.; Santos, A.; B. Veigas; Bras, N.; Faria, A.; Calhau, C.; de Freitas, V.; P.V. Baptista; Mateus, N.; Fernandes, A. R.; Fernandes, I. (Sci Rep, 2019)
Anthocyanins may protect against a myriad of human diseases. However few studies have been conducted to evaluate their bioavailability so their absorption mechanism remains unclear. This study aimed to evaluate the role of two glucose transporters (GLUT1 and GLUT3) in anthocyanins absorption in the human gastric epithelial cells (MKN-28) by using gold nanoparticles to silence these transporters. Anthocyanins were purified from purple fleshed sweet potatoes and grape skin. Silencing of GLUT1 and/or GLUT3 mRNA was performed by adding AuNP@GLUT1 and/or AuNP@GLUT3 to MKN-28 cells. Downregulation of mRNA expression occurred concomitantly with the reduction in protein expression. Malvidin-3-O-glucoside (Mv3glc) transport was reduced in the presence of either AuNP@GLUT1 and AuNP@GLUT3, and when both transporters were blocked simultaneously. Peonidin-3-(6'-hydroxybenzoyl)-sophoroside-5-glucoside (Pn3HBsoph5glc) and Peonidin-3-(6'-hydroxybenzoyl-6''-caffeoyl)-sophoroside-5-glucoside (Pn3HBCsoph5glc) were assayed to verify the effect of the sugar moiety esterification at glucose B in transporter binding. Both pigments were transported with a lower transport efficiency compared to Mv3glc, probably due to steric hindrance of the more complex structures. Interestingly, for Pn3HBCsoph5glc although the only free glucose is at C5 and the inhibitory effect of the nanoparticles was also observed, reinforcing the importance of glucose on the transport regardless of its position or substitution pattern. The results support the involvement of GLUT1 and GLUT3 in the gastric absorption of anthocyanins.
Oliveira, HelderRoma-Rodrigues, Catarina Santos, Ana Veigas, Bruno Bras, Natercia Faria, Ana Calhau, Conceicao de Freitas, Victor Baptista, Pedro V Mateus, Nuno Fernandes, Alexandra R Fernandes, Iva eng Research Support, Non-U.S. Gov't England Sci Rep. 2019 Jan 28;9(1):789. doi: 10.1038/s41598-018-37283-2.
Keywords: Anthocyanins/chemistry/pharmacokinetics/*pharmacology; Biological Transport; Cell Line; Epithelial Cells/cytology/metabolism; Gastric Absorption; Gastric Mucosa/*cytology/metabolism; Glucose Transporter Type 1/antagonists & inhibitors/*genetics; Glucose Transporter Type 3/antagonists & inhibitors/*genetics; Glucosides/chemistry/pharmacokinetics; Gold/*pharmacology; Humans; Ipomoea batatas/chemistry; Metal Nanoparticles; Models, Biological; Vitis/chemistry

Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug - Santos, M. M.; Raposo, L. R.; Carrera, G. V. S. M.; Costa, A.; Dionisio, M.; P.V. Baptista; Fernandes, A. R.; Branco, L. C. (ChemMedChem, 2019)
Herein we report the synthesis of novel ionic liquids (ILs) and organic salts by combining ibuprofen as anion with ammonium, imidazolium, or pyridinium cations. The methodology consists of an acid-base reaction of neutral ibuprofen with cation hydroxides, which were previously prepared by anion exchange from the corresponding halide salts with Amberlyst A-26(OH). In comparison with the parent drug, these organic salts display higher solubility in water and biological fluids and a smaller degree of polymorphism, which in some cases was completely eliminated. With the exception of [C16 Pyr][Ibu] and [N1,1,2,2OH1 ][Ibu], the prepared salts did not affect the viability of normal human dermal fibroblasts or ovarian carcinoma (A2780) cells. Therefore, these ibuprofen-based ionic liquids may be very promising lead candidates for the development of effective formulations of this drug.
Santos, Miguel MRaposo, Luis R Carrera, Goncalo V S M Costa, Alexandra Dionisio, Madalena Baptista, Pedro V Fernandes, Alexandra R Branco, Luis C eng Research Support, Non-U.S. Gov't Germany ChemMedChem. 2019 May 6;14(9):907-911. doi: 10.1002/cmdc.201900040. Epub 2019 Apr 10.
Keywords: *API-ILs; *cytotoxicity; *Drug Compounding; *ibuprofen; *ionic liquids; *polymorphism; Anti-Inflammatory Agents, Non-Steroidal/*chemistry; Cell Line, Tumor; Cells, Cultured; Female; Fibroblasts/cytology/drug effects; Humans; Ibuprofen/*chemistry; Ionic Liquids/*chemistry; Ovarian Neoplasms/pathology; Salts/*chemistry

Liquid biopsies in myeloid malignancies - Abdulmawjood, Bilal; Catarina Roma-Rodrigues; Alexandra R. Fernandes; Pedro V. Baptista (2019)
Hematologic malignancies are the most common type of cancer affecting children and young adults, and encompass diseases, such as leukemia, lymphoma, and myeloma, all of which impact blood associated tissues such as the bone marrow, lymphatic system, and blood cells. Clinical diagnostics of these malignancies relies heavily on the use of bone marrow samples, which is painful, debilitating, and not free from risks for leukemia patients. Liquid biopsies are based on minimally invasive assessment of markers in the blood (and other fluids) and have the potential to improve the efficacy of diagnostic/therapeutic strategies in leukemia patients, providing a useful tool for the real time molecular profiling of patients. The most promising noninvasive biomarkers are circulating tumor cells, circulating tumor DNA, microRNAs, and exosomes. Herein, we discuss the role of assessing these circulating biomarkers for the understanding of tumor progression and metastasis, tumor progression dynamics through treatment and for follow-up.
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Keywords: circulating tumor cells; circulating tumor DNA; Exosomes; leukemia; Liquid biopsy; microRNAs

N-Heterocyclic olefin catalysis for the ring opening of cyclic amidine compounds: a pathway to the synthesis of ε-caprolactam and γ-lactam-derived amines - Peixoto, Daniela; Malta, Gabriela; Cruz, Hugo; Barroso, Sónia; Carvalho, Ana Luisa; Ferreira, Luisa Maria; Branco, Paula Serio (The Journal of Organic Chemistry, 2019)
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doi: 10.1021/acs.joc.8b02823

Nanotheranostics Targeting the Tumor Microenvironment - Roma-Rodrigues, C.; Pombo, I.; Raposo, L.; Pedrosa, P.; Fernandes, A. R.; P.V. Baptista (Front Bioeng Biotechnol, 2019)
Cancer is considered the most aggressive malignancy to humans, and definitely the major cause of death worldwide. Despite the different and heterogenous presentation of the disease, there are pivotal cell elements involved in proliferation, differentiation, and immortalization, and ultimately the capability to evade treatment strategies. This is of utmost relevance when we are just beginning to grasp the complexity of the tumor environment and the molecular "evolution" within. The tumor micro-environment (TME) is thought to provide for differentiation niches for clonal development that results in tremendous cancer heterogeneity. To date, conventional cancer therapeutic strategies against cancer are failing to tackle the intricate interplay of actors within the TME. Nanomedicine has been proposing innovative strategies to tackle this TME and the cancer cells that simultaneously provide for biodistribution and/or assessment of action. These nanotheranostics systems are usually multi-functional nanosystems capable to carry and deliver active cargo to the site of interest and provide diagnostics capability, enabling early detection, and destruction of cancer cells in a more selective way. Some of the most promising multifunctional nanosystems are based on gold nanoparticles, whose physic-chemical properties have prompt for the development of multifunctional, responsive nanomedicines suitable for combinatory therapy and theranostics. Herein, we shall focus on the recent developments relying on the properties of gold nanoparticles as the basis for nanotheranostics systems against the heterogeneity within the TME.
Roma-Rodrigues, CatarinaPombo, Ines Raposo, Luis Pedrosa, Pedro Fernandes, Alexandra R Baptista, Pedro V eng Review Switzerland Front Bioeng Biotechnol. 2019 Aug 14;7:197. doi: 10.3389/fbioe.2019.00197. eCollection 2019.
Keywords: cancer therapy; diagnostic; Gold nanoparticles; Nanomedicine; nanotheranostics; Tumor microenvironment

A new Cu(II)-O-Carvacrotinate complex: Synthesis, characterization and biological activity - Sutradhar, M.; Fernandes, A. R.; Paradinha, F.; Rijo, P.; Garcia, C.; Roma-Rodrigues, C.; Pombeiro, A. J. L.; Charmier, A. J. (J Inorg Biochem, 2019)
Herein, we report the first example of the synthesis of a novel type of Cu(II) complex based on a natural product ligand derived from carvacrol. The copper(II) complex [Cu(DCA)2(EtOH)]2.2EtOH (1, HDCAO-carvacrotinic acid) has been synthesized and characterized by elemental analysis, IR spectroscopy, ESI-MS and single crystal X-ray analysis. Complex 1 and the carvacrotinic acid (2, HDCA) have been studied towards their antimicrobial and antiproliferative activities. For both compounds the antimicrobial activity was assessed against a panel of Gram-positive and Gram-negative bacteria and yeasts. The microdilution method allowed the determination of their Minimum Inhibitory Concentration (MIC) and minimum bactericidal concentration (MBC). Interestingly, both compounds seem to be more effective on yeasts rather than bacteria especially against C. albicans. Regarding the antimicrobial properties, the compounds appear to present a bacteriostatic behaviour, rather than bactericide. The antiproliferative effect of complex 1, O-carvacrotinic acid (HDCA) 2 and carvacrol (CA) 3 used as a reference to compare their antitumoral activity, was examined in 4 human tumor cell lines (ovarian carcinoma (A2780), colorectal carcinoma (HCT116), lung adenocarcinoma (A549) and breast adenocarcinoma (MCF7)) and in normal human primary fibroblasts. Complex 1 exhibits a moderate cytotoxic activity against ovarian carcinoma cells (A2780), with no cytotoxicity in normal primary human fibroblasts. The moderate cytotoxicity observed in A2780 cells was due to an increase of cell apoptosis.
Sutradhar, ManasFernandes, Alexandra R Paradinha, Fabiana Rijo, Patricia Garcia, Catarina Roma-Rodrigues, Catarina Pombeiro, Armando J L Charmier, Adilia Januario eng Research Support, Non-U.S. Gov't J Inorg Biochem. 2019 Jan;190:31-37. doi: 10.1016/j.jinorgbio.2018.09.018. Epub 2018 Sep 29.
Keywords: *Antimicrobial activity; *Antiproliferative agent; *Carvacrol; *Cu(II) complex; *Human tumor cell lines; *O-carvacrotinic acid; Anti-Bacterial Agents/pharmacology; Antifungal Agents/pharmacology; Cell Line, Tumor; Cell Proliferation/drug effects; Coordination Complexes/*chemical synthesis/chemistry/*pharmacology; Copper/*chemistry; Crystallography, X-Ray; Drug Screening Assays, Antitumor; Humans; Microbial Sensitivity Tests

New insights about the monomer and homodimer structures of the human AOX1 - Ferreira, P.; Cerqueira, N. M. F. S. A.; Coelho, C.; Fernandes, P. A.; Romão, M.J.; Ramos, M. J. (Physical Chemistry Chemical Physics, 2019)
Human aldehyde oxidase (hAOX1) is a molybdenum dependent enzyme that plays an important role in the metabolism of various compounds either endogenous or xenobiotics. Due to its promiscuity, hAOX1 plays a major role in the pharmacokinetics of many drugs and therefore has gathered a lot of attention from the scientific community and, particularly, from the pharmaceutical industry. In this work, homology modelling, molecular docking and molecular dynamics simulations were used to study the structure of the monomer and dimer of human AOX. The results with the monomer of hAOX1 allowed to shed some light on the role played by thioridazine and two malonate ions that are co-crystalized in the recent X-ray structure of hAOX1. The results show that these molecules endorse several conformational rearrangements in the binding pocket of the enzyme and these changes have an impact in the active site topology as well as in the stability of the substrate (phthalazine). The results show that the presence of both molecules open two gates located at the entrance of the binding pocket, from which results the flooding of the active site. They also endorse several modifications in the shape of the binding pocket (namely the position of Lys893) that, together with the presence of the solvent molecules, favour the release of the substrate to the solvent. Further insights were also obtained with the assembled homodimer of hAOX1. The allosteric inhibitor (THI) binds closely to the region where the dimerization of both monomers occur. These findings suggest that THI can interfere with protein dimerization.
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Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product - C. Kourmentza; D. Araujo; Sevrin, C.; C. Roma-Rodriques; Lia Ferreira, J.; Freitas, F; Dionisio, M.; P.V. Baptista; Fernandes, A. R.; C. Grandfils; Reis, M. A. M. (Bioresour Technol, 2019)
While screening for polyhydroxyalkanoate (PHA) producing strains, using glycerol rich by-product as carbon source, it was observed that extracellular polymers were also secreted into the culture broth. The scope of this study was to characterize both intracellular and extracellular polymers, produced by Pseudomonas putida NRRL B-14875 and Pseudomonas chlororaphis DSM 50083, mostly focusing on those novel extracellular polymers. It was found that they fall into the class of bioemulsifiers (BE), as they showed excellent emulsion stability against different hydrocarbons/oils at various pH conditions, temperature and salinity concentrations. Cytotoxicity tests revealed that BE produced by P. chlororaphis inhibited the growth of highly pigmented human melanoma cells (MNT-1) by 50% at concentrations between 150 and 200mug/mL, while no effect was observed on normal skin primary keratinocytes and melanocytes. This is the first study reporting mcl-PHA production by P. putida NRRL B-14785 and bioemulsifier production from both P. putida and P. chlororaphis strains.
Kourmentza, ConstantinaAraujo, Diana Sevrin, Chantal Roma-Rodriques, Catarina Lia Ferreira, Joana Freitas, Filomena Dionisio, Madalena Baptista, Pedro V Fernandes, Alexandra R Grandfils, Christian Reis, Maria A M eng England Bioresour Technol. 2019 Jun;281:31-40. doi: 10.1016/j.biortech.2019.02.066. Epub 2019 Feb 15.
Keywords: Bioemulsifiers; Cell Line, Tumor; Cell Proliferation/drug effects; Crude glycerol; cytotoxicity; Glycerol/*metabolism; Humans; Melanoma/pathology; Polyhydroxyalkanoates; Polyhydroxyalkanoates/*biosynthesis; Pseudomonas chlororaphis; Pseudomonas putida; Pseudomonas/*metabolism

Platinum(ii) complexes showing high cytotoxicity toward A2780 ovarian carcinoma cells - Choroba, K.; Machura, B.; Raposo, L. R.; Malecki, J. G.; Kula, S.; Pajak, M.; Erfurt, K.; Maron, A. M.; Fernandes, A. R. (Dalton Trans, 2019)
2,6-Bis(thiazol-2-yl)pyridines functionalized with 9-anthryl (L(1)), 9-phenanthryl (L(2)), and 1-pyrenyl (L(3)) groups were used for the preparation of [Pt(L(n))Cl]CF3SO3 (1-3). The constitution of the Pt(ii) complexes was determined by (1)H and (13)C NMR spectroscopy, HR-MS spectrometry, elemental analysis and X-ray analysis (for (1)). The electrochemical and photophysical properties of [Pt(L(n))Cl]CF3SO3 were compared with the behaviour of the Pt(ii) complexes with aryl-substituted 2,2':6',2''-terpyridine ligands. What is noteworthy is that the coordination ability of dtpy toward the Pt(ii) centre was investigated for the first time. All complexes were tested in vitro by MTS assay on four tumor cell lines, A2780 (ovarian carcinoma), HTC116 (colon rectal carcinoma), MCF7 (breast adenocarcinoma), and PC3 (prostate carcinoma) and on normal primary fibroblasts. Compounds (1-3) showed a dose dependent antiproliferative effect in the A2780 cell line with (3) > (2) > (1) and this loss of A2780 cell viability was due to a combination of an apoptotic cell death mechanism via mitochondria and autophagic cell death. Exposure to IC50 concentration of (2) induced an increase in the number of apoptotic nuclei and a depolarization of the mitochondrial membrane which is consistent with the induction of apoptosis while exposure to IC50 concentration of (3) showed an increase in the apoptotic nuclei with a slight hyperpolarization of the mitochondrial membrane that might indicate an initial step of apoptosis induction. The complexes (2) and (3) induce an increase in the production of intracellular ROS which is associated with the trigger of the apoptotic pathways. The ROS production was augmented by the presence of oxidants and correlated with an increase of oxygen radicals. The IC50 of (2) and (3) (4.4 muM and 2.9 muM, respectively) was similar to the IC50 of cisplatin (3.4 muM) in the A2780 cell line, which together with their low cytotoxicity in normal fibroblasts, demonstrates their potential for further studies.
Choroba, KatarzynaMachura, Barbara Raposo, Luis R Malecki, Jan G Kula, Slawomir Pajak, Michal Erfurt, Karol Maron, Anna M Fernandes, Alexandra R eng England Dalton Trans. 2019 Sep 14;48(34):13081-13093. doi: 10.1039/c9dt02894c. Epub 2019 Aug 14.
Keywords: Antineoplastic Agents/chemistry/*pharmacology; Apoptosis/drug effects; Cell Line, Tumor; Cell Survival/drug effects; Drug Screening Assays, Antitumor; Electrochemistry; Female; Humans; Models, Molecular; Molecular Conformation; Organoplatinum Compounds/chemistry/*pharmacology; Ovarian Neoplasms/*pathology; Reactive Oxygen Species/metabolism

Reversible water driven chirality inversion in cellulose-based helices isolated from Erodium awns - Ana P.C. Almeida; Querciagrossa, Lara; Silva, Pedro E. S.; Gonçalves, Filipa; Canejo, João P; Almeida, Pedro L; Godinho, Maria Helena; Zannoni, Claudio (Soft Matter, 2019)
Among the movements observed in some cellulosic structures produced by plants are those that involve the dispersion and burial of seeds, as for example in Erodium from the Geraniaceae plant family. Here we report on a simple and efficient strategy to isolate and tune cellulose-based hygroscopic responsive materials from Erodium awns’ dead tissues. The stimuli-responsive material isolated forms left-handed (L) or right-handed (R) helical birefringent transparent ribbons in the wet state that reversibly change to R helices when the material dries. The humidity-driven motion of dead tissues is most likely due to a composite material made of cellulose networks of fibrils imprinted by the plant at the nanoscale, which reinforces a soft wall polysaccharide matrix. The inversion of the handedness is explained using computational simulations considering filaments that contract and expand asymmetrically. The awns of Erodium are known to present hygroscopic movements, forming R helices in the dry state, but the possibility of actuating chirality via humidity suggests that these cellulose-based skeletons, which do not require complicated lithography and intricate deposition techniques, provide a diverse range of applications from intelligent textiles to micro-machines.
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Streptococcus dysgalactiae subsp. dysgalactiae isolated from milk of the bovine udder as emerging pathogens: In vitro and in vivo infection of human cells and zebrafish as biological models - Alves-Barroco, C.; Roma-Rodrigues, C.; Raposo, L. R.; Bras, C.; Diniz, M.; Caco, J.; Costa, P. M.; Santos-Sanches, I.; Fernandes, A. R. (Microbiologyopen, 2019)
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is a major cause of bovine mastitis and has been regarded as an animal-restricted pathogen, although rare infections have been described in humans. Previous studies revealed the presence of virulence genes encoded by phages of the human pathogen Group A Streptococcus pyogenes (GAS) in SDSD isolated from the milk of bovine udder with mastitis. The isolates SDSD VSD5 and VSD13 could adhere and internalize human primary keratinocyte cells, suggesting a possible human infection potential of bovine isolates. In this work, the in vitro and in vivo potential of SDSD to internalize/adhere human cells of the respiratory track and zebrafish as biological models was evaluated. Our results showed that, in vitro, bovine SDSD strains could interact and internalize human respiratory cell lines and that this internalization was dependent on an active transport mechanism and that, in vivo, SDSD are able to cause invasive infections producing zebrafish morbidity and mortality. The infectious potential of these isolates showed to be isolate-specific and appeared to be independent of the presence or absence of GAS phage-encoded virulence genes. Although the infection ability of the bovine SDSD strains was not as strong as the human pathogenic S. pyogenes in the zebrafish model, results suggested that these SDSD isolates are able to interact with human cells and infect zebrafish, a vertebrate infectious model, emerging as pathogens with zoonotic capability.
Alves-Barroco, CinthiaRoma-Rodrigues, Catarina Raposo, Luis R Bras, Catarina Diniz, Mario Caco, Joao Costa, Pedro M Santos-Sanches, Ilda Fernandes, Alexandra R eng Research Support, Non-U.S. Gov't England Microbiologyopen. 2019 Jan;8(1):e00623. doi: 10.1002/mbo3.623. Epub 2018 Mar 25.
Keywords: *bovine; *host adhesion/internalization; *Streptococcus dysgalactiae subsp. dysgalactiae; *systemic infection; *zebrafish; Animals; Bacterial Adhesion; Biological Variation, Population; Cattle; Cells, Cultured; Disease Models, Animal; Endocytosis; Epithelial Cells/microbiology; Humans; Mammary Glands, Animal/microbiology; Mastitis, Bovine/*microbiology/*pathology; Milk/*microbiology; Models, Biological; Streptococcal Infections/*microbiology/*pathology; Streptococcus/*isolation & purification/pathogenicity; Survival Analysis; Virulence; Zebrafish

Structural aspects of a trimetallic CuII derivative: cytotoxicity and anti-proliferative activity on human cancer cell lines - Kuheli Das; Amitabha Datta; Chiara Massera; Catarina Roma-Rodrigues; Mariana Barroso; Pedro V. Baptista; Alexandra R. Fernandes (Journal of Coordination Chemistry, 2019)
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Structural characterization and biological properties of silver(I) tris(pyrazolyl)methane sulfonate - Almeida, J.; Roma-Rodrigues, C.; Mahmoud, A. G.; Guedes da Silva, M.F.C.; Pombeiro, A. J. L.; Martins, L. M. D. R. S.; P.V. Baptista; Fernandes, A. R. (J Inorg Biochem, 2019)
The water-soluble 1D helical coordination polymer [Ag(Tpms)]n (1) [Tpms=tris(pyrazolyl)methane sulfonate, (-)O3SC(pz)3; pz=pyrazolyl] was synthesized and fully characterized, its single-crystal X-ray diffraction analysis revealing the ligand acting as a bridging chelate N3-donor ligand. The antiproliferative potential of 1 was performed on two human tumour cell lines, A2780 and HCT116, and in normal fibroblasts, with a much higher effect in the former cell line (IC50 of 0.04muM) as compared to the latter cell line and to normal fibroblasts. Compound 1 does not alter cell cycle progression but interferes with the adherence of A2780 cells triggering cell apoptosis. Apoptosis appears to occur via the extrinsic pathway (no changes in mitochondria membrane potential, reactive oxygen species (ROS) and pro-apoptotic (B-cell lymphoma 2 (BCL-2) associated protein (BAX))/anti-apoptotic (BCL-2) ratio) being this hypothesis also supported by the presence of silver mainly in the supernatants of A2780 cells. Results also indicated that cell death via autophagy was triggered. Proteomic analysis allowed us to confirm that compound 1 is able to induce a stress response in A2780 cells that is related with its antiproliferative activity and the trigger of apoptosis.
Almeida, JoanaRoma-Rodrigues, Catarina Mahmoud, Abdallah G Guedes da Silva, M Fatima C Pombeiro, Armando J L Martins, Luisa M D R S Baptista, Pedro V Fernandes, Alexandra R eng Research Support, Non-U.S. Gov't J Inorg Biochem. 2019 Oct;199:110789. doi: 10.1016/j.jinorgbio.2019.110789. Epub 2019 Jul 19.
Keywords: *2-D electrophoresis; *Antiproliferative activity; *Cell death; *Ovarian carcinoma; *Silver complexes; Antineoplastic Agents/chemistry/pharmacology; Apoptosis/drug effects; Cell Line; Cell Line, Tumor; Electrophoresis, Gel, Two-Dimensional; Female; HCT116 Cells; Humans; Magnetic Resonance Spectroscopy; Ovarian Neoplasms/metabolism; Polymers/*chemistry; Pyrazoles/*chemistry/pharmacology; Reactive Oxygen Species; Silver/*chemistry

Targeting Cancer Resistance via Multifunctional Gold Nanoparticles - Pedrosa, P.; Corvo, M. L.; Ferreira-Silva, M.; Martins, P.; MC Carvalheiro; Costa, P. M.; Martins, C.; Martins, L. M. D. R. S.; P.V. Baptista; Fernandes, A. R. (Int J Mol Sci, 2019)
Resistance to chemotherapy is a major problem facing current cancer therapy, which is continuously aiming at the development of new compounds that are capable of tackling tumors that developed resistance toward common chemotherapeutic agents, such as doxorubicin (DOX). Alongside the development of new generations of compounds, nanotechnology-based delivery strategies can significantly improve the in vivo drug stability and target specificity for overcoming drug resistance. In this study, multifunctional gold nanoparticles (AuNP) have been used as a nanoplatform for the targeted delivery of an original anticancer agent, a Zn(II) coordination compound [Zn(DION)2]Cl2 (ZnD), toward better efficacy against DOX-resistant colorectal carcinoma cells (HCT116 DR). Selective delivery of the ZnD nanosystem to cancer cells was achieved by active targeting via cetuximab, NanoZnD, which significantly inhibited cell proliferation and triggered the death of resistant tumor cells, thus improving efficacy. In vivo studies in a colorectal DOX-resistant model corroborated the capability of NanoZnD for the selective targeting of cancer cells, leading to a reduction of tumor growth without systemic toxicity. This approach highlights the potential of gold nanoformulations for the targeting of drug-resistant cancer cells.
Pedrosa, PedroCorvo, M Luisa Ferreira-Silva, Margarida Martins, Pedro Carvalheiro, Manuela Colla Costa, Pedro M Martins, Carla Martins, L M D R S Baptista, Pedro V Fernandes, Alexandra R eng UID/Multi/04378/2013,SFRH/BD/120030/2016, PD/BD/105734/2014/Fundacao para a Ciencia e a Tecnologia Switzerland Int J Mol Sci. 2019 Nov 5;20(21). pii: ijms20215510. doi: 10.3390/ijms20215510.
Keywords: Animals; Antineoplastic Agents/*administration & dosage/pharmacology; Cancer; cancer resistance; Cetuximab/administration & dosage/pharmacology; Colorectal Neoplasms/*drug therapy; Coordination Complexes/administration & dosage/pharmacology; Doxorubicin/pharmacology; Drug Delivery Systems; Drug Resistance, Neoplasm/*drug effects; Gold nanoparticles; Gold/*chemistry; HCT116 Cells; Humans; Male; Metal Nanoparticles/*chemistry; Mice; Mice, Inbred BALB C; Nanomedicine; Zinc/*administration & dosage/pharmacology

Targeting Tumor Microenvironment for Cancer Therapy - Roma-Rodrigues, C.; Mendes, R.; P.V. Baptista; Fernandes, A. R. (Int J Mol Sci, 2019)
Cancer development is highly associated to the physiological state of the tumor microenvironment (TME). Despite the existing heterogeneity of tumors from the same or from different anatomical locations, common features can be found in the TME maturation of epithelial-derived tumors. Genetic alterations in tumor cells result in hyperplasia, uncontrolled growth, resistance to apoptosis, and metabolic shift towards anaerobic glycolysis (Warburg effect). These events create hypoxia, oxidative stress and acidosis within the TME triggering an adjustment of the extracellular matrix (ECM), a response from neighbor stromal cells (e.g., fibroblasts) and immune cells (lymphocytes and macrophages), inducing angiogenesis and, ultimately, resulting in metastasis. Exosomes secreted by TME cells are central players in all these events. The TME profile is preponderant on prognosis and impacts efficacy of anti-cancer therapies. Hence, a big effort has been made to develop new therapeutic strategies towards a more efficient targeting of TME. These efforts focus on: (i) therapeutic strategies targeting TME components, extending from conventional therapeutics, to combined therapies and nanomedicines; and (ii) the development of models that accurately resemble the TME for bench investigations, including tumor-tissue explants, "tumor on a chip" or multicellular tumor-spheroids.
Roma-Rodrigues, CatarinaMendes, Rita Baptista, Pedro V Fernandes, Alexandra R eng UID/Multi/04378/2019/Ministerio da Ciencia, Tecnologia e Ensino Superior SFRH/BPD/124612/2016/Ministerio da Ciencia, Tecnologia e Ensino Superior Review Switzerland Int J Mol Sci. 2019 Feb 15;20(4). pii: ijms20040840. doi: 10.3390/ijms20040840.
Keywords: *Molecular Targeted Therapy; *Tumor Microenvironment; Animals; cancer therapy; Humans; models for tumor microenvironment study; Models, Biological; Nanomedicine; nanomedicines; Neoplasms/*pathology/*therapy; Neovascularization, Pathologic/therapy; tumor development; Tumor microenvironment

Thinner and Higher Efficient Silicon and Perovskite Solar Cells with Photonic structuring - Mendes, Manuel J. (Materials 2019, 2019)

Electricity, the silver bullet for the deep decarbonisation of the energy system? Cost-effectiveness analysis for Portugal. - Fortes, Patricia; Simoes, Sofia; Gouveia, João Pedro; Júlia Seixas (Applied Energy, 2019)

Synthesis of thermoelectric magnesium-silicide pastes for 3D printing, electrospinning and low-pressure spray - Marques, AC; Miglietta, Davide; G. Gaspar; Baptista, A. C.; Gaspar, A.; Perdigão, A.; Soares, I.; Bianchi, C.; Sousa, D.; Morais Faustino, B. M.; Amaral, V. S.; Santos, T.; et al. (Materials for Renewable and Sustainable Energy, 2019)

Accessibility to peptidoglycan is important for recognition of Gram-positive bacteria in Drosophila - F. Vaz; Kounatidis, I; G. Covas; Parton, R M; Harkiolaki, M; Davis, I; S. R. Filipe*; P. Ligoxygakis* (Cell Reports, 2019)

Adding detailed transmission constraints to a long-term integrated assessment model – A case study for Brazil using the TIMES model - Miranda, R.; Simoes, S.; Szklo, A.; Schaeffer, R. (Energy, 2019)

Affinity‐triggered assemblies based on a designed peptide‐peptide affinity pair - Cláudia Fernandes; Ana S Pina; Arménio J.M. Barbosa; Inês Padrão; Filipa Duarte; Cátia Andreia; Silva Teixeira; Vitor Alves; Paula Gomes; Tiago G. Fernandes; Ana M G C Dias; Roque, Ana C A (Biotechnology Journal, 2019)
Affinity‐triggered assemblies rely on affinity interactions as the driving force to assemble physically‐crosslinked networks. WW domains are small hydrophobic proteins binding to proline‐rich peptides that are typically produced in the insoluble form. Previous works attempted the biological production of the full WW domain in tandem to generate multivalent components for affinity‐triggered hydrogels. In this work, an alternative approach was followed by engineering a 13‐mer minimal version of the WW domain that retains the ability to bind to target proline‐rich peptides. Both ligand and target peptides were produced chemically and conjugated to multivalent polyethylene glycol, yielding two components. Upon mixing, they together form soft biocompatible affinity‐triggered assemblies, stable in stem cell culture media, and displaying mechanical properties in the same order of magnitude as for those hydrogels formed with the full WW protein in tandem.

Aldehyde Oxidases as Enzymes in Phase I Drug Metabolism - Mota, Cristiano; Santos Silva, Teresa; Terao, Mineko; Garattini, Enrico; Romão, Maria João; Leimkuehler, Silke (Pharmaceutical Biocatalysis, 2019)

All-Thin-Film Perovskite/C–Si Four-Terminal Tandems: Interlayer and Intermediate Contacts Optimization - Chapa, Manuel; Alexandre, Miguel F.; Mendes, Manuel J.; Hugo Águas; Elvira Fortunato; Rodrigo Martins (ACS Applied Energy Materials, 2019)

Biochemical responses in Danio rerio following exposure to CdS and ZnS Quantum Dots - A.Rocha; Sousa, D.; Ferreira, I.; Diniz, M. S. (Annals of Medicine, 2019)

Biosensor for direct bioelectrocatalysis detection of nitric oxide using nitric oxide reductase incorporated in carboxylated single-walled carbon nanotubes/lipidic bilayer nanocomposite - Gomes, FO; Maia, L. B.; Loureiro, JA; Pereira, MC; Delerue-Matos, C.; Moura, I.; Moura, J. J. G.; Morais, S. (Bioelectrochem, 2019)

Characterisation of glass and painting materials from 18th century hand-painted glass slides used for projection with Magic Lanterns - Ângela Santos; Otero, Vanessa; Vilarigues, Márcia (Interim Meeting of the ICOM-CC Glass and Ceramics Working Group − "Recent Advances in Glass and Ceramics Conservation 2019", 2019)
With the invention of the Magic Lantern during the 17th century, new perspectives for the pre-cinema universe started to emerge. During the following two centuries, this instrument achieved extraordinary success on all social media. One of the first stages of the production of glass slides for projection with magic lanterns was the hand-painting technique that nowadays represents a significant challenge for conservation professionals due to the diversity of painting materials used and their exposure to aggressive conditions during the projections. A set of Italian 18th-century hand-painted glass slides from the Cinemateca Portuguesa – Museu do Cinema's collection are currently being studied. The glass was characterised using Energy Dispersive X-Ray Fluorescence Spectrometry (µ-EDXRF) and the identification of the painting materials was performed by Fourier Transform Infrared Spectroscopy (µ-FTIR) and Raman Spectroscopy (µ-Raman). Further investigation will be conducted with Optical Microscopy (OM), UV-Vis Fibre-Optic Reflectance Spectroscopy (FORS), and Microspectrofluorimetry. The combination of different analytical techniques on glass slides examples allowed us to identify the composition of the glass and paintings materials, as well as to determine their current state of preservation.

Cholesteric-type cellulosic structures: from plants to applications - Ana P.C. Almeida; Canejo, João P; Almeida, Pedro L; Godinho, Maria Helena (Liquid Crystals, 2019)

A comparative genomics approach for identifying host-range determinants in Streptococcus thermophilus bacteriophages - P. Szymczak; Rau, M H; J. M. Monteiro; M. G. Pinho; S. R. Filipe; F. K. Vogensen; Zeidan, A A; T. Janzen (Scientific Reports, 2019)

Contactless high-speed eddy current inspection of unidirectional carbon fiber reinforced polymer - Machado, M.A.; Antin, K.-N.; Rosado, L.S.; Vilaça, P.; Santos, T.G. (Composites Part B: Engineering, 2019)
This paper presents the development and the results of a customized eddy current (EC) non-destructive testing (NDT) system for highly demanding online inspection conditions. Several planar eddy current array probes were designed, numerically simulated and experimentally compared for the inspection of low conductivity unidirectional carbon fibre reinforced polymer (CFRP) ropes. The inspections were performed using a dedicated scanner device at 4 m/s with 3 mm probe lift-off where defects under 1 mm were detected with an excellent SNR. Different defect morphologies and sizes, such as broken fibres and lateral cuts, were successful detected and compared to conventional probes.

Correspondence on “Preorganization and Cooperation for Highly Efficient and Reversible Capture of Low-Concentration CO2 by Ionic Liquids” - Zanatta, Marcileia; Simon, Nathalia M; dos Santos, Francisco P; Corvo, Marta C.; Cabrita, Eurico J.; Dupont, Jairton (Angewandte Chemie International Edition, 2019)
The preorganization and cooperation mechanism of imide‐based ionic liquids reported in a recent Communication was evocated to rationalize the extremely high gravimetric CO2 capture displayed by these fluids. An analysis of the reported spectroscopic evidences together with additional experiments led to the proposition of an alternative, simpler, and feasible mechanism involving the formation of bicarbonate.
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Croatian geological heritage related to historical mining and quarrying - Marta Mileusnić; et al (European Geologist Journal, 2019)

Customized tracheal design using 3D printing of a polymer hydrogel: influence of UV laser cross-linking on mechanical properties - Ana Filipa Cristovão; David Sousa; Filipe Silvestre; Ropio, Inês; Ana Gaspar; Célia Henriques; Velhinho, Alexandre; Baptista, Ana Catarina; Miguel Faustino; Ferreira, Isabel (3D Print Med, 2019)

Customized tracheal design using 3D printing of a polymer hydrogel: influence of UV laser cross-linking on mechanical properties - Ana Filipa Cristovão; David Sousa; Filipe Silvestre; Ropio, Inês; Ana Gaspar; Célia Henriques; Velhinho, Alexandre; Baptista, Ana Catarina; Miguel Faustino; Ferreira, Isabel (3D Printing in Medicine, 2019)
Background The use of 3D printing of hydrogels as a cell support in bio-printing of cartilage, organs and tissue has attracted much research interest. For cartilage applications, hydrogels as soft materials must show some degree of rigidity, which can be achieved by photo- or chemical polymerization. In this work, we combined chemical and UV laser polymeric cross-linkage to control the mechanical properties of 3D printed hydrogel blends. Since there are few studies on UV laser cross-linking combined with 3D printing of hydrogels, the work here reported offered many challenges. Methods Polyethylene glycol diacrylate (PEGDA), sodium alginate (SA) and calcium sulphate (CaSO4) polymer paste containing riboflavin (vitamin B2) and triethanolamine (TEOHA) as a biocompatible photoinitiator was printed in an extrusion 3D plotter using a coupled UV laser. The influence of the laser power on the mechanical properties of the printed samples was then examined in unconfined compression stress-strain tests of 1 × 1 × 1 cm3 sized samples. To evaluate the adhesion of the material between printed layers, compression measurements were performed along the parallel and perpendicular directions to the printing lines. Results At a laser density of 70 mW/cm2, Young’s modulus was approximately 6 MPa up to a maximum compression of 20% in the elastic regime for both the parallel and perpendicular measurements. These values were within the range of biological cartilage values. Cytotoxicity tests performed with Vero cells confirmed the cytocompatibility. Conclusions We printed a partial tracheal model using optimized printing conditions and proved that the materials and methods developed may be useful for printing of organ models to support surgery or even to produce customized tracheal implants, after further optimization.

The dawn of urban energy planning – synergies between energy and urban planning for São Paulo (Brazil) megacity - Collaço, F.; Simoes, S. G.; Dias, L.; Duic, N.; Seixas, J.; Bermann, C. (Journal of Cleaner Production, 2019)

Designed affinity ligands to capture human serum albumin - dos Santos, R,; Figueiredo C,; Viecinski AC,; Pina AS,; Barbosa AJM,; Roque, A. C. A. (Journal of Chromatography A, 2019)
Human serum albumin (HSA) in an important therapeutic agent and disease biomarker, with an increasing market demand. By proteins and drugs that bind to HSA as inspiration, a combinatorial library of 64 triazine-based ligands was rationally designed and screened for HSA binding at physiological conditions. Two triazine-based lead ligands (A3A2 and A6A5), presenting more than 50% HSA bound and high enrichment factors, were selected for further studies. Binding and elution conditions for HSA purification from human plasma were optimized for both ligands. The A6A5 adsorbent yielded a purified HSA sample with 98% purity at 100% recovery yield under mild binding and elution conditions.

Determination of the magnetic properties and orientation of the heme axial ligands of PpcA from G. metallireducens by paramagnetic NMR - Fernandes, Tomás M.; Leonor Morgado; Salgueiro, , Carlos A.; Turner, David L. (Journal of Inorganic Biochemistry, 2019)
The rising interest in the use of Geobacter bacteria for biotechnological applications demands a deep understanding of how these bacteria are able to thrive in a variety of environments and perform extracellular electron transfer. The Geobacter metallireducens bacterium can couple the oxidation of a wide range of compounds to the reduction of several extracellular acceptors, including heavy metals, toxic organic compounds or electrode surfaces. The periplasmic c-type cytochrome PpcA from this bacterium is a member of a family composed of five periplasmic triheme cytochromes, which are important to bridge the electron transfer between the cytoplasm and the extracellular environment. To better understand the functional mechanism of PpcA it is essential to obtain structural data for this cytochrome. In this work, the geometry of the heme axial ligands, as well as the magnetic properties of the hemes were determined for the oxidized form of the cytochrome, using the 13C NMR chemical shifts of the heme α-substituents. The results were further compared with those previously obtained for the homologous cytochrome from Geobacter sulfurreducens. The orientations of the axial histidine planes and the magnetic properties of the hemes are conserved in both proteins. Overall, the results obtained allowed the definition of the orientation of the magnetic axes of PpcA from G. metallireducens, which will be used as constraints to assist the solution structure determination of the cytochrome in the oxidized form.
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Keywords: Multiheme cytochrome; NMR; Paramagnetic systems

Development of polymeric anepectic meshes: auxetic metamaterials with negative thermal expansion - Joana Raminhos; Borges, João Borges; Velhinho, Alexandre (Smart Materials and Structures, 2019)
his paper reports the application of additive manufacturing technology to fabricate bi-dimensional lightweight composite meshes capable of demonstrating auxetic properties (negative Poisson's ratio (NPR)) in combination with negative thermal expansion (NTE) behaviour, using as constituent materials polymers that do not exhibit NTE behaviour. To describe the combination of NPR and NTE characteristics, the designation of 'anepectic' is being proposed. Each mesh, obtained from varying either the material combination or the design parameters, was tested on a heated silicone bath to study the effects of the different combinations on the coefficient of thermal expansion (CTE). It was found that all meshes studied demonstrated a successful combination of NPR and NTE behaviours, and it was revealed that there is a possibility to tailor the meshes to activate the NTE behaviour within a chosen range of temperatures. For an extreme case, a Poisson's ratio of −0.056, along with a CTE of −1568 × 10−6 K−1 has been achieved.

Direct electrochemical reduction of carbon dioxide by a molybdenum-containing formate dehydrogenase - Cordas, C. M.; Campaniço, M; Baptista, R; Maia, L.; Moura, I.; Moura, J. J. G. (J Inorg Biochem, 2019)

Effect of film thickness in gelatin hybrid gels for artificial olfaction - Esteves C,; Santos GMC,; Alves C,; Palma S,; Porteira AR,; Filho J,; Costa HA; Alves VD,; Faustino BMM,; Ferreira, I.; Gamboa H,; Roque, A. C. A. (Materials Today Bio, 2019)
Artificial olfaction is a fast-growing field aiming to mimic natural olfactory systems. Olfactory systems rely on a first step of molecular recognition in which volatile organic compounds (VOCs) bind to an array of specialized olfactory proteins. This results in electrical signals transduced to the brain where pattern recognition is performed. An efficient approach in artificial olfaction combines gas-sensitive materials with dedicated signal processing and classification tools. In this work, films of gelatin hybrid gels with a single composition that change their optical properties upon binding to VOCs were studied as gas-sensing materials in a custom-built electronic nose. The effect of films thickness was studied by acquiring signals from gelatin hybrid gel films with thicknesses between 15 and 90 μm when exposed to 11 distinct VOCs. Several features were extracted from the signals obtained and then used to implement a dedicated automatic classifier based on support vector machines for data processing. As an optical signature could be associated to each VOC, the developed algorithms classified 11 distinct VOCs with high accuracy and precision (higher than 98%), in particular when using optical signals from a single film composition with 30 μm thickness. This shows an unprecedented example of soft matter in artificial olfaction, in which a single gelatin hybrid gel, and not an array of sensing materials, can provide enough information to accurately classify VOCs with small structural and functional differences.

Effect of film thickness in gelatine hybrid gels for artificial olfaction - Carina Esteves; Gonçalo M.C. Santos; Cláudia Alves; Susana I C J Palma; Ana R. Porteira; Henrique M.A. Costa; Alves, Vitor D.; Bruno M. Morais Faustino; Ferreira, Isabel; Gamboa, Hugo (Materials Today Bio, 2019)

Electroanalytical characterization of the direct Marinobacter hydrocarbonoclasticus nitric oxide reductase-catalysed nitric oxide and dioxygen reduction - Gomes, F.; Maia, L.; Cordas, C.; Moura, I.; Delerue-Matos, C.; Moura, J. J. G.; Morais, S. (Bioelectrochem, 2019)

Electrospun biodegradable chitosan based-poly(urethane urea) scaffolds for soft tissue engineering - Tânia Vieira; Silva, Jorge Carvalho; A.M. Botelho do Rego; Borges, João Borges; Célia Henriques (Materials Science and Engineering: C, 2019)
The composition and architecture of a scaffold determine its supportive role in tissue regeneration. In this work, we demonstrate the feasibility of obtaining a porous electrospun fibrous structure from biodegradable polyurethanes (Pus) synthesized using polycaprolactone-diol as soft segment and, as chain extenders, chitosan (CS) and/or dimethylol propionic acid. Fourier transform infrared spectroscopy and proton nuclear magnetic resonance confirmed the syntheses. Fibre mats' properties were analysed and compared with those of solvent cast films. Scanning electron microscopy images of the electrospun scaffolds revealed fibres with diameters around 1 μm. From tensile tests, we found that Young's modulus increases with CS content and is higher for films (2.5 MPa to 6.5 MPa) than for the corresponding fibre mats (0.8 MPa to 3.2 MPa). The use of CS as the only chain extender improves recovery ratio and resilience. From X-ray diffraction, a higher crystalline degree was identified in fibre mats than in the corresponding films. Films' wettability was enhanced by the presence of CS as shown by the decrease of water contact angle. X-ray photoelectron spectroscopy revealed that while ester groups are predominant at the films' surface, ester and urethanes are present in similar concentrations at fibres' surface, favouring the interaction with water molecules. Both films and fibres undergo hydrolytic degradation. In vitro evaluation was performed with human dermal fibroblasts. No PU sample revealed cytotoxicity. Cells adhered to fibre mats better than to films and proliferation was observed only for samples of CS-containing PUs. Results suggest that electrospun fibres of CS-based polyurethanes are good candidate scaffolds for soft tissue engineering.

Energy Poverty Policies and Measures in 5 EU Countries: A Comparative Study. - Ioanna Kyprianou; Despina Serghides; Annais Varo; Gouveia, João Pedro; Diana Kopeva; Lina Murauskaite (Energy and Buildings, 2019)

Energy poverty vulnerability index: A multidimensional tool to identify hotspots for local action. - Gouveia, João Pedro; Pedro Palma; Simoes, Sofia (Energy Reports, 2019)

Evaluation of Different Non-destructive Testing Methods to Detect Imperfections in Unidirectional Carbon Fiber Composite Ropes - Kim-Niklas Antin; Miguel A. Machado; Telmo G. Santos; Pedro Vilaça (Journal of Nondestructive Evaluation, 2019)
Online monitoring of carbon fiber reinforced plastic (CFRP) ropes requires non-destructive testing (NDT) methods capable of detecting multiple damage types at high inspection speeds. Three NDT methods are evaluated on artificial and realistic imperfections in order to assess their suitability for online monitoring of CFRP ropes. To support testing, the microstructure and electrical conductivity of a carbon fiber rope is characterized. The compared methods are thermography via thermoelastic stress analysis, ultrasonic testing with commercial phased array transducers, and eddy current testing, supported by tailor-made probes. While thermoelastic stress analysis and ultrasonics proved to be accurate methods for detecting damage size and the shape of defects, they were found to be unsuitable for high-speed inspection of a CFRP rope. Instead, contactless inspection using eddy currents is a promising solution for real-time online monitoring of CFRP ropes at high inspection speeds.

Executing requests concurrently in state machine replication - Tiago Vale (FCT–NOVA, 2019)

Extraction of Cellulose Nanocrystals with Structure I and II and Their Applications for Reduction of Graphene Oxide and Nanocomposite Elaboration - Faouzia Khili; Joao Borges; Almeida, Pedro L; Rabah Boukherroub; Amel Dakhlaoui Omrani (Waste and Biomass Valorization, 2019)
The aim of the present study is to investigate the effect of the hydrolysis process on the properties of nanocrystalline cellulose (NCC) isolated from different precursors and the subsequent use of the extracted NCC for the reduction of graphene oxide (GO). The raw materials (almond and peanut shells) chosen for the isolation of cellulose were selected on the basis of their abundance and their poorly investigation in the production of NCC. Microcrystalline cellulose (MCC) was firstly extracted by alkali and bleaching treatments, then hydrolyzed under different processes to produce NCC polymorphs with structure I (NCC-I) and NCC structure II (NCC-II). The Fourier transform infrared spectroscopy, the X-ray diffraction (XRD) and the 13C NMR studies of the alkali and bleached products confirmed the formation of cellulose type I with high purity and good crystallinity, while scanning electron microscopy (SEM) showed micrometric fibers with lengths reaching 80 µm. Sulfuric acid treatment of these microfibers results in NCC type I or II, depending on the hydrolysis process. SEM of the NCC samples exhibited nanorods with diameter and aspect ratio in the range of 20–40 and 20–25 nm, respectively. Thermogravimetric analysis (TGA) of the MCC and NCC products indicated stable materials with a degradation temperature reaching 240 and 200 °C for MCC and NCC, respectively. The other part of our work concerns the use of the obtained cellulose nanocrystals (type II) for the preparation of reduced graphene oxide composite (NCC/RGO), to demonstrate the reducing properties of the isolated NCCII.

Extraction of Cellulose Nanocrystals with Structure I and II and Their Applications for Reduction of Graphene Oxide and Nanocomposite Elaboration - Faouzia Khili; Borges, João Borges; Almeida, Pedro L; Rabah Boukherroub; Amel Dakhlaoui Omrani (Waste and Biomass Valorization, 2019)
The aim of the present study is to investigate the effect of the hydrolysis process on the properties of nanocrystalline cellulose (NCC) isolated from different precursors and the subsequent use of the extracted NCC for the reduction of graphene oxide (GO). The raw materials (almond and peanut shells) chosen for the isolation of cellulose were selected on the basis of their abundance and their poorly investigation in the production of NCC. Microcrystalline cellulose (MCC) was firstly extracted by alkali and bleaching treatments, then hydrolyzed under different processes to produce NCC polymorphs with structure I (NCC-I) and NCC structure II (NCC-II). The Fourier transform infrared spectroscopy, the X-ray diffraction (XRD) and the 13C NMR studies of the alkali and bleached products confirmed the formation of cellulose type I with high purity and good crystallinity, while scanning electron microscopy (SEM) showed micrometric fibers with lengths reaching 80 µm. Sulfuric acid treatment of these microfibers results in NCC type I or II, depending on the hydrolysis process. SEM of the NCC samples exhibited nanorods with diameter and aspect ratio in the range of 20–40 and 20–25 nm, respectively. Thermogravimetric analysis (TGA) of the MCC and NCC products indicated stable materials with a degradation temperature reaching 240 and 200 °C for MCC and NCC, respectively. The other part of our work concerns the use of the obtained cellulose nanocrystals (type II) for the preparation of reduced graphene oxide composite (NCC/RGO), to demonstrate the reducing properties of the isolated NCCII.

Flexible and transparent ReRAM devices for system on panel (SOP) application - Kiazadeh, Asal; Deueurmeier, Jonas (Advances in Non-Volatile Memory and Storage Technology (Second Edition), 2019)

Fluorescence anisotropy of fluorescein varies according to pH: lessons for binding studies - Castro, N.S.S.; Laia, C. A. T.; Moura, I.; Carepo, M. S. (J Photochem Photobiol A: Chemistry, 2019)

Free Marine natural products databases for biotechnology and bioengineering - Barbosa, AJM; Roque, A. C. A. (Biotechnology Journal, 2019)
Marine organisms and microorganisms are a source of natural compounds with unique chemical features. These chemical properties are useful for the discovery of new functions and applications of Marine Natural Products (MNP). To extensively exploit the potential implementations of MNPs, they are gathered in chemical databases consenting their study and screening for applications of biotechnological interest. However, classification of MNPs is currently poor in generic chemical databases. The present availability of free‐access focused MNPs databases is scarce and the molecular diversity of these databases is still very low when compared to paid‐access ones. In this review paper, the current scenario of free‐access MNP databases is presented as well as the hindrances involved in their development, mainly compound dereplication. Examples and opportunities on using freely accessible MNP databases in several important areas of biotechnology are also assessed. The scope of this paper is as well to notify the latent potential of these information sources for the discovery and development of new MNPs in biotechnology, and push future efforts to develop a public domain MNP database freely available for the scientific community.

From beams to glass: determining compositions to study provenance and production techniques - Vilarigues, Márcia; Inês Coutinho; Teresa Medici; Luís Cerqueira Alves; Bernard Gratuze; Andreia Machado (Physical Sciences Reviews, 2019)

Graphene oxide reinforced aluminium matrix nanostructured composited fabricated by accumulative roll bonding - F. Ferreira; Ferreira, I.; E. Camacho; F. Lopes; Marques, AC; A. Velhinho (Composites Part B: Engineering, 2019)

Grisaille in Historical Written Sources - Carla Machado; Andreia Machado; Teresa Palomar; Vilarigues, Márcia (Journal of Glass Studies, 2019)

High speed inspection of UD CFRP composites - Miguel A. Machado; Antin, Kim Niklas; Rosado, Luís S.; Pedro Vilaça; Telmo G. Santos (58th Annual Conference of the British Institute of Non-Destructive Testing, NDT 2019, 2019)
Online monitoring of carbon fibre reinforced polymer (CFRP) components requires a Non-Destructive Testing (NDT) method capable of contactless sensing of damage, while enabling high inspection speeds needed for monitoring large components. Eddy current testing (ECT) of CFRP components has great potential for two reasons. First, ECT probes are capable of operating without contact, although minimizing the lift-off is preferred. Second, impedance analysers with high sample rates make high-speed inspection possible. This research assesses the damage detection capabilities of eddy current probes on CFRP samples with artificial and realistic damage. To support the aptitude of the ECT method for these needs, the CFRP material is characterized and numerical simulations are performed in order to develop optimized and tailored ECT probes for the detection of defects with different morphologies, namely fibre breakage and delaminations, and to take into consideration the highly anisotropic electrical bulk resistivity of the CFRP material. Different ECT probes were designed, produced and experimentally validated. The experiments were performed at a high inspection speed (4 m/s) and the high sensitivity of the probes was demonstrated.
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Highly transparent copper iodide thin film thermoelectric generator on a flexible substrate - Coroa, J.; Morais Faustino, B. M.; Marques, AC; Bianchi, C.; Koskinen, T.; T. Juntunen; I. Tittonen; Ferreira, I. (RSC Advances, 2019)

Hydrolytic zinc metallopeptides using a computational multi-state design approach - H. Carvalho; R. Branco; F. Leite; Matzapetakis, M.; Roque, A. C. A.; Iranzo, O. (Catalysis Science Technology, 2019)
Hydrolytic zinc enzymes are common targets for protein design. The versatility of the zinc chemistry can be combined with the usage of small protein scaffolds for biocatalytic applications. Despite this, the computational design of metal-containing proteins remains challenging due to the need to properly model protein–metal interactions. We addressed these issues by developing a computational multi-state design approach of artificial zinc hydrolases based on small protein scaffolds. The zinc-finger peptide Sp1f2 was redesigned to accommodate a catalytic zinc centre and the villin headpiece C-terminal subdomain HP35 was de novo designed for metal-binding and catalytic activity. Both metallopeptides exhibited metal-induced folding (KZnP,app ≈ 2 × 105 M−1) and hydrolytic activity (k2 ≈ 0.1 M−1 s−1) towards an ester substrate. By focusing on the inherent flexibility of small proteins and their interactions with the metal ion by molecular dynamics simulations and spectroscopic studies, we identified current limitations on computational design of metalloenzymes and propose how these can be overcome by integrating information of protein–metal interactions in long time scale simulations.

Identification and Antibiotic-Susceptibility Profiling of Infectious Bacterial Agents: A Review of Current and FutureTrends - Gaetano Maugeri; Iana Lychko; Rita Sobral; Roque, Ana C A (Biotechnology Journal, 2019)
Antimicrobial resistance is one of the most worrying threats to humankind with extremely high healthcare costs associated. The current technologies used in clinical microbiology to identify the bacterial agent and profile antimicrobial susceptibility are time‐consuming and frequently expensive. As a result, physicians prescribe empirical antimicrobial therapies. This scenario is often the cause of therapeutic failures, causing higher mortality rates and healthcare costs, as well as the emergence and spread of antibiotic resistant bacteria. As such, new technologies for rapid identification of the pathogen and antimicrobial susceptibility testing are needed. This review summarizes the current technologies, and the promising emerging and future alternatives for the identification and profiling of antimicrobial resistance bacterial agents, which are expected to revolutionize the field of clinical diagnostics.

Impact of Sensing Film’s Production Method on Classification Accuracy by Electronic Nose - Ana Padua; Gruber, Jonas; Gamboa, Hugo; Roque, Ana Cecília A (Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, 2019)
The development of gas sensing materials is relevant in the field of non-invasive biodevices. In this work, we used an electronic nose (E-nose) developed by our research group, which possess versatile and unique sensing materials. These are gels that can be spread over the substrate by Film Coating or Spin Coating. This study aims to evaluate the influence of the sensing film spreading method selected on the classification capabilities of the E-nose. The methodology followed consisted of performing an experiment where the E-nose was exposed to 13 different pure volatile organic compounds. The sensor array had two sensing films produced by Film Coating, and other two produced by Spin Coating. After data collection, a set of features was extracted from the original signal curves, and the best were selected by Recursive Feature Elimination. Then, the classification performance of Multinomial Logistic regression, Decision Tree, and Naíve Bayes was evaluated. The results showed that both s preading methods for sensing film’s production are adequate since the estimated error of classification was inferior to 4 % for all the classification tools applied.

Injectable Hydrogels Based on Pluronic/Water Systems Filled with Alginate Microparticles for Biomedical Applications - Diogo J. Ramos; Henrique Carrêlo; Borges, João Paulo; Nuria Calero Romero; Jenifer Santos Garcia; Maria Teresa Cidade (Materials, 2019)
A (model) composite system for drug delivery was developed based on a thermoresponsive hydrogel loaded with microparticles. We used Pluronic F127 hydrogel as the continuous phase and alginate microparticles as the dispersed phase of this composite system. It is well known that Pluronic F127 forms a gel when added to water in an appropriate concentration and in a certain temperature range. Pluronic F127 hydrogel may be loaded with drug and injected, in its sol state, to act as a drug delivery system in physiological environment. A rheological characterization allowed the most appropriate concentration of Pluronic F127 (15.5 wt%) and appropriate alginate microparticles contents (5 and 10 wt%) to be determined. Methylene blue (MB) was used as model drug to perform drug release studies in MB loaded Pluronic hydrogel and in MB loaded alginate microparticles/Pluronic hydrogel composite system. The latter showed a significantly slower MB release than the former (10 times), suggesting its potential in the development of dual cargo release systems either for drug delivery or tissue engineering.

Inspection of composite parts produced by additive manufacturing: Air-coupled ultrasound and thermography - Miguel A. Machado; Inácio, Patrick L.; Santos, Rui A.; Gomes, André F.; Martins, Ana P.; Carvalho, Marta S.; Telmo G. Santos (58th Annual Conference of the British Institute of Non-Destructive Testing, NDT 2019, 2019)
Polymeric parts produced by Fused Deposition Modelling (FDM) Additive Manufacturing (AM) has no special safety requirements, and therefore, NDT is not required. However, the use of AM to produce Fibre Reinforcement Thermoplastics (FRTP) parts means that structural applications with safety requirements are envisaged, demanding reliable NDT methods. This paper presents experimental results and numerical simulation by Finite Element Method (FEM) of the NDT inspection of different parts of polymeric and RFTP composite materials. The parts were produced by FDM Additive Manufacturing and different delamination defects were introduced at different positions and with different dimensions and morphologies. Two different NDT techniques were used, exploiting different inspection parameters: air-coupled ultrasound, using frequencies between 50 and 400 kHz and active transient thermography, in both reflection and transition modes. The influence of the curvature of the parts was analysed, from the experimental point of view, and the results were compared with different numerical simulation strategies. It was shown that, both NDT techniques can detect the defects, with good spatial resolution, being the thermography reflection mode the fastest and expedite for curvature parts. The numerical simulation corroborates the experimental results allowing a deeper insight on the physical phenomena involved.
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Interplay between the potential of photovoltaic systems and agricultural land use - Dias, L.; Gouveia, J. P.; Lourenço, P.; Seixas, J. (Land Use Policy, 2019)

Intrinsically Electrochromic Deep Eutectic Solvents - Cruz, H.; N. Jordão; M. Dionísio; Pina, F; Branco, L. C. (Chemistry Select, 2019)
DOI: 10.1002/slct.201801054

Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug - Santos, M. M.; Raposo, L. R.; Carrera, G. V. S. M.; Costa, A.; Dionisio, M.; P.V. Baptista; Fernandes, A. R.; Branco, L. C. (ChemMedChem, 2019)
DOI: 10.1002/cmdc.201900040

Large-Area Paper Batteries with Ag and Zn/Ag Screen-Printed Electrodes - Esperança Garcia, Diogo Miguel; Taborda Martins Pereira, Ana Sofia; Antonio Carranca Almeida; Santana Roma, Urbez; Ben Aissa Soler, Alejandra; Paul D. Lacharmoise; Isabel Maria das Merces Ferreira; Claudia Custod́io Delgado Simao (ACS Omega, 2019)

Ligand accessibility to heme cytochrome b5 coordinating sphere and enzymatic activity enhancement upon tyrosine ionization - Samhan-Arias, A. K.; Cordas, C. M.; Carepo, M. S.; Maia, L. B.; Gutierrez-Merino, C.; Moura, I.; Moura, J. J. G. (J Biol Inorg Chem, 2019)

Lightwave trapping in thin film solar cells with improved photonic-structured front contacts - Sanchez-Sobrado, Olalla; Mendes, Manuel J.; Haque, Sirazul; Mateus, Tiago; Hugo Aguas; Elvira Fortunato; Rodrigo Martins (Journal of Materials Chemistry C, 2019)

Magic Lantern Glass Slides Materials and Techniques: The First Multi-Analytical Study - Beatriz Rodrigues; Ângela Santos; Maria João Melo; Otero, Vanessa; Vilarigues, Márcia (Heritage, 2019)

Mapping the energy performance gap of dwelling stock at high-resolution scale: Implications for thermal comfort in Portuguese households. - Pedro Palma; Gouveia, João Pedro; Simoes, Sofia (Energy and Buildings, 2019)

Mesoporous Silica vs. Organosilica Composites to Desulfurize Diesel - Ribeiro, Susana O.; Granadeiro, Carlos M.; Corvo, Marta C.; Pires, João; Campos-Martin, Jose M.; Baltazar de Castro; Balula, Salete S. (Frontiers in Chemistry, 2019)
Download Article Export citation 1,049 TOTAL VIEWS Article has an altmetric score of 3 Suggest a Research Topic > SHARE ON 0 0 0 New ORIGINAL RESEARCH ARTICLE Front. Chem., 14 November 2019 | https://doi.org/10.3389/fchem.2019.00756 Mesoporous Silica vs. Organosilica Composites to Desulfurize Diesel Susana O. Ribeiro1, Carlos M. Granadeiro1, Marta C. Corvo2, João Pires3, José M. Campos-Martin4, Baltazar de Castro1 and Salete S. Balula1* 1LAQV-REQUIMTE, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade Do Porto, Porto, Portugal 2CENIMAT/I3N, Departamento de Ciência dos Materiais, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal 3Faculdade de Ciências, Centro de Química e Bioquímica and CQE, Universidade de Lisboa, Lisbon, Portugal 4Grupo de Energía y Química Sostenibles (EQS), Instituto de Catálisis y Petroleoquímica, CSIC, Madrid, Spain The monolacunary Keggin-type [PW11O39]7− (PW11) heteropolyanion was immobilized on porous framework of mesoporous silicas, namely SBA-15 and an ethylene-bridged periodic mesoporous organosilica (PMOE). The supports were functionalized with a cationic group (N-trimethoxysilypropyl-N, N, N-trimethylammonium, TMA) for the successful anchoring of the anionic polyoxometalate. The PW11@TMA-SBA-15 and PW11@TMA-PMOE composites were evaluated as heterogeneous catalysts in the oxidative desulfurization of a model diesel. The PW11@TMA-SBA-15 catalyst showed a remarkable desulfurization performance by reaching ultra-low sulfur levels (<10 ppm) after only 60 min using either a biphasic extractive and catalytic oxidative desulfurization (ECODS) system (1:1 MeCN/diesel) or a solvent-free catalytic oxidative desulfurization (CODS) system. Furthermore, the mesoporous silica composite was able to be recycled for six consecutive cycles without any apparent loss of activity. The promising results have led to the application of the catalyst in the desulfurization of an untreated real diesel supplied by CEPSA (1,335 ppm S) using the biphasic system. The system has proved to be a highly efficient process by reaching desulfurization values higher than 90% for real diesel during three consecutive cycles.
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Molecular Interactions in Ionic Liquids: The NMR Contribution towards Tailored Solvents - Lopes, Mónica M; Barrulas, Raquel V; Paiva, Tiago G.; Ferreira, Ana S. D.; Zanatta, Marcileia; Corvo, Marta C. (Nuclear Magnetic Resonance, 2019)
Ionic liquids have been on the spotlight of chemical research field in the last decades. Their physical properties (low vapor pressure, thermal stability, and conductivity) and the possibility of fine tuning make them a versatile class of compounds for a wide range of applications, such as catalysis, energy, and material sciences. Ionic liquids can establish multiple intermolecular interactions with solutes such as electrostatic, van der Waals, or hydrogen bonds. The prospect of designing ionic liquid structures toward specific applications has attracted the attention to these alternative solvents. However, their rational design demands a molecular detailed view, and Nuclear Magnetic Resonance is a unique and privileged technique for this purpose, as it provides atomic resolution and at the same time enables the study of dynamic information. In this chapter, we provide an overview about the application of Nuclear Magnetic Resonance spectroscopy techniques as a methodology for the rational design of ionic liquids as solvents for small organic compounds, CO2 capture, and polymers such as cellulose focusing mainly in the last 10 years.
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Molybdenum and tungsten enzymes: a brief overview - Cordas, C. M.; Moura, J. J. G. (Coord Chem Rev, 2019)

NiII -ATCUN-catalyzed tyrosine nitration in the presence of nitrite and sulfite - B.K. Maiti; Maia, L. B.; Moura, I.; Moura, J. J. G. (Chem Eur J, 2019)

NMR Methodology for a Rational Selection of Ionic Liquids: Extracting Polyphenols - Barrulas, R.V.; Paiva, T.G; Corvo, Mc (Separation and Purification Technology, 2019)
Extracts from plants have considerable significance as bioactive compounds with several pharmacological applications. Polyphenols have attracted the attention as anti-inflammatory and anti-oxidative materials. Nonetheless, the amount of these compounds in the extracts is typically very low. Consequently, green extraction techniques with higher efficiency for phenolic compounds are of paramount importance. Ionic liquids (ILs), which are also known as designer solvents can be used to extract polyphenols, however the search for ideal solvents is mostly done by trial and error. In this work, nuclear magnetic resonance (NMR) is used to study the profile of ILs molecular interactions with model compounds that mimic polyphenols. The ILs that exhibit the strongest molecular interactions were proven to have the highest efficiency when extracting polyphenols from matcha Japanese green tea, known to be extremely rich in these compounds. Both the IL cation and anion have an influence on the solvent behaviour. The best IL solvents for matcha polyphenols were imidazolium derivatives with shorter alkyl side chains and weakly basic anions such as tricyanomethanide, dicyanamide and triflate. Thus, the NMR approach avoids an exhaustive testing and allows the rational selection of the best ILs for the extraction.
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Non-destructive microstructural analysis by electrical conductivity: Comparison with hardness measurements in different materials - Sorger, G.L.; Oliveira, J.P.; Inácio, P.L.; Enzinger, N.; Vilaça, P.; Miranda, R.M.; Santos, T.G. (Journal of Materials Science and Technology, 2019)
The use of non-destructive evaluation (NDE) techniques for assessing microstructural changes in processed materials is of particular importance as it can be used to assess, qualitatively, the integrity of any material/structure. Among the several NDE techniques available, electrical conductivity measurements using eddy currents attract great attention owing to its simplicity and reliability. In this work, the electrical conductivity profiles of friction stir processed Ti6Al4V, Cu, Pb, S355 steel and gas tungsten arc welded AISI 304 stainless steel were determined through eddy currents and four-point probe. In parallel, hardness measurements were also performed. The profiles matched well with the optical macrographs of the materials: while entering in the processed region a variation in both profiles was always observed. One particular advantage of electrical conductivity profiles over hardness was evident: it provides a better resolution of the microstructural alterations in the processed materials. Moreover, when thermomechanical processing induces microstructural changes that modify the magnetic properties of a material, eddy currents testing can be used to qualitatively determine the phase fraction in a given region of the material. A qualitative relation between electrical conductivity measurements and hardness is observed.

Nontoxic glasses: Preparation, structural, electrical and biological properties - Sílvia R. Gavinho; Pedro R. Prezas; Diogo J. Ramos; Sá-Nogueira, Isabel; Borges, João Borges; M. Carmo Lança; Silva, Jorge Carvalho; Célia Henriques; Pires, Eduardo; Jakka Suresh Kumar; Manuel P. Graça (Applied Ceramics Technology, 2019)
Bacterial infections affect about 1 in 5 patients who receive a dental implant within 5 years of surgery. To avoid the implant rejection it is necessary for the development of innovative biomaterials, with addition or substitution of the ions, for implant coatings that promote a strong bond with the new host bone and antibacterial action. The objective of this work was to synthesize a bioactive glass with different silver concentrations to evaluate their antibacterial performance. The glasses were synthesized with up to 2% silver content by melt-quenching. Structural, morphological, biological, and electrical properties of all samples were studied. The biological behavior was evaluated through cytotoxicity tests and antibacterial activity. The structural analysis shows that the introduction of silver do not promote significant changes, not altering the advantageous properties of the bioglass of the bioglass. It was verified that the glasses with a silver content from 0.5% to 2%, completely prevented the growth of both Staphylococcus aureus and Escherichia coli while being nontoxic toward mammalian cells. Therefore, these bioglasses are promising materials to be used in the production of dental implants with antimicrobial activity.

Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product - C. Kourmentza; D. Araujo; C. Sevrinc; C. Roma-Rodriques; J. Lia Ferreira; Freitas, F; M. Dionísio; P.V. Baptista; Fernandes, A. R.; C. Grandfils; Reis, M. A. M. (Bioresource Technology, 2019)
DOI: 10.1016/j.biortech.2019.02.066

On the influence of imidazolium ionic liquids on cellulose derived polymers - Paiva, T.; Echeverria, C.; M. H. Godinho; P. L. Almeida; Corvo, Mc (European Polymer Journal, 2019)
The demand for better cellulose solvents has driven the search for new and improved materials to enable the processing of this polysaccharide. Ionic liquids have been debated for a long time as interesting alternatives, but the molecular details on the solubilization mechanism have been a matter of controversy. Herein, for the first time, the structure and dynamics of hydroxypropylcellulose (HPC) liquid crystal solutions were probed in the presence of imidazolium ionic liquids (ILs), conjugating rheological measurements with magnetic resonance spectroscopy. This study provides a characterization of the solutions macroscopic behaviour, where the liquid crystalline (LC) properties were maintained. Using ILs with different side chain lengths, the influence of the hydrophobic IL domain in the solvation abilities of ILs towards a cellulose derived polymer was accessed, providing experimental evidence on these interactions.
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An Optimized E-nose for Efficient Volatile Sensing and Discrimination - Gonçalo Santos; Claudia Alves; Ana Carolina Pádua; Susana Palma; Gamboa, Hugo; Roque, Ana Cecília A (Proceedings of the 12th International Joint Conference on Biomedical Engineering Systems and Technologies - Volume 1: BIODEVICES, 2019)
Electronic noses (E-noses), are usually composed by an array of sensors with different selectivities towards classes of VOCs (Volatile Organic Compounds). These devices have been applied to a variety of fields, including environmental protection, public safety, food and beverage industries, cosmetics, and clinical diagnostics. This work demonstrates that it is possible to classify eleven VOCs from different chemical classes using a single gas sensing biomaterial that changes its optical properties in the presence of VOCs. To accomplish this, an in-house built E-nose, tailor-made for the novel class of gas sensing biomaterials, was improved and combined with powerful machine learning techniques. The device comprises a delivery system, a detection system and a data acquisition and control system. It was designed to be stable, miniaturized and easy-to-handle. The data collected was pre-processed and features and curve fitting parameters were extracted from the original response. A recursive feature selection method was applied to select the best features, and then a Support Vector Machine classifier was implemented to distinguish the eleven distinct VOCs. The results show that the followed methodology allowed the classification of all the VOCs tested with 94.6% (± 0.9%) accuracy.

Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells - Alexandre, Miguel; Chapa, Manuel; Haque, Sirazul; Mendes, Manuel J.; Hugo Águas; Elvira Fortunato; Rodrigo Martins (ACS Applied Energy Materials, 2019)

The pentaglycine bridges of Staphylococcus aureus peptidoglycan are essential for cell integrity - J. M. Monteiro; G. Covas; D. Rausch; S. R. Filipe; T. Schneider; H. G. Sahl; M. G. Pinho (Scientific Reports, 2019)

Photoluminescent Glasses and Their Applications - Laia, César; Ruivo, Andreia (Fluorescence in Industry, 2019)

Photonic-structured TiO2 for high-efficiency, flexible and stable Perovskite solar cells - Haque, Sirazul; Mendes, Manuel J.; Sanchez-Sobrado, Olalla; Hugo Águas; Elvira Fortunato; Rodrigo Martins (Nano Energy, 2019)

Polyoxomolybdate based ionic-liquids as active catalysts for oxidative desulfurization of simulated diesel - Mirante, Fatima; Gomes, Neide; Corvo, Marta C.; Gago, Sandra; Balula, Salete S. (Polyhedron, 2019)
This work compares the stability and the catalytic efficiency of different ionic liquid phosphomolybdates ([BPy]3[PMo12O40] and [BMIM]3[PMo12O40]) with a cationic (propylpyridinium) functionalized mesoporous silica nanoparticle composite (PMo12O40@PPy-MSN). These were used as solid catalysts for the oxidative desulfurization of a multicomponent model diesel using hydrogen peroxide as oxidant and a polar immiscible extraction solvent. Ionic liquid ([BMIM][PF6] was successfully used as solvent to extract sulfur compounds from model diesel. The ionic liquid phosphomolybdates showed partial solubility in the ionic liquid phase, occurring some decomposition of their Keggin structure in the soluble reaction media, probably caused by their interaction with oxidant. On the other hand, the phosphomolybdate composite PMo12O40@PPy-MSN presented high structural stability and only negligible leaching occurrence after various consecutive reaction cycles. The model diesel was near complete desulfurized after 3 h and consecutive desulfurization cycles were performed without loss of activity. Therefore, the immobilization of Keggin phosphomolybdate structure [PMo12O40]3− using cationic propylpyridinium silica nanoparticle is an assertive strategy to produce stable and active heterogeneous catalysts.
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A Process Engineering Approach to Improve Production of P(3HB) by Cupriavidus necator from Used Cooking Oil (International Journal of Polymer Science, 2019)
DOI: 10.1155/2019/2191650

Recent advances in the manipulation of circularly polarised light with cellulose nanocrystal films - Fernandes, S N; Lopes, L.F.; M. H. Godinho (Current Opinion in Solid State & Materials Science, 2019)

Revisiting anti-tuberculosis therapeutic strategies that target the peptidoglycan structure and synthesis - M. J. Catalão; S. R. Filipe; M. Pimentel (Front. Microbiol, 2019)

Source and reduction of nitrous oxide - Pauleta, S. R.; Carepo, M. S.; Moura, I. (Coord Chem Rev, 2019)

Stability under humidity, UV-light and bending of AZO films deposited by ALD on Kapton - Marques, AC; Faria, J.; Perdigão, P.; B. M. M. Faustino; Ritasalo, Riina; Costabello, Katiuscia; R.C. da Silva; Ferreira, I. (Scientific Reports, 2019)

Sustainable and Resource Efficient Cities Platform – SureCity holistic simulation and optimization for smart cities - Pardo-García, N.; Simoes, S. G.; Dias, L.; Sandgren, A.; Suna, D.; Krook-Riekkola, A. (Journal of Cleaner Production, 2019)

Synthesis and Characterization of Magnetic Nanoparticles and their internalization on Tumor Cell Lines - Catarina IP Chaparro; Liliana R Loureiro; Manuel Almeida Valente; Paula A. Videira; Borges, João Paulo; Paula I P Soares (2019 IEEE 6th Portuguese Meeting on Bioengineering (ENBENG), 2019)
Truncated sialylated O-glycans, such as cell-surface carbohydrate antigen sialyl-Tn (STn) are overexpressed by several cancer types, but not by the respective normal tissues. STn expression is associated with oncogenesis and metastatic ability of cancer cells, with reduced overall survival and lack of response to chemotherapy. Advances in nanomedicine have resulted in rapid development of biocompatible superparamagnetic iron oxide nanoparticles (SPIONs) with considerable potential in cancer treatment. Therefore, in this study SPIONs coated with oleic acid (OA) or dimercaptosuccinic acid (DMSA) were developed and characterized for internalization in two breast cancer cell lines: cell line expressing the STn antigen and the corresponding control. SPIONs with an average diameter of 8 nm showed superparamagnetic behavior and high potential to be used as magnetic hyperthermia agents. OA and DMSA coating provided high stability of SPIONs in physiological conditions while not changing their main properties. NPs internalization studies showed a higher accumulation of DMSA coated NPs in the breast cancer MDA-MB-231 WT cell line. In MDA-MB-231 cell line expressing STn both coated NPs showed a similar accumulation. Therefore, STn antigen can act as a receptor capable of detecting and covalently bind to the molecules present on NPs surface and induce their cellular uptake by endocytosis.

Synthesis of thermoelectric magnesium-silicide pastes for 3D printing, electrospinning and low-pressure spray - Marques, Ana; Miglietta, Davide; G. Gaspar; Baptista, Ana Catarina; Gaspar, A.; Perdigão, P.; Iris Soares; Bianchi, Catarina; David Sousa; Bruno M. Morais Faustino; Amaral, V. S.; Santos, T.; et al. (Materials for Renewable and Sustainable Energy, 2019)
In this work, eco-friendly magnesium-silicide (Mg2Si) semiconducting (n-type) thermoelectric pastes for building components concerning energy-harvesting devices through 3D printing, spray and electrospinning were synthetized and tested for the first time. The Mg2Si fine powders were obtained through the combination of ball milling and thermal annealing under Ar atmosphere. While the latter process was crucial for obtaining the desired Mg2Si phase, the ball milling was indispensable for homogenizing and reducing the grain size of the powders. The synthetized Mg2Si powders exhibited a large Seebeck coefficient of ~ 487 µV/K and were blended with a polymeric solution in different mass ratios to adjust the paste viscosity to the different requirements of 3D printing, electrospinning and low-pressure spray. The materials produced in every single stage of the paste synthesis were characterized by a variety of techniques that unequivocally prove their viability for producing thermoelectric parts and components. These can certainly trigger further research and development in green thermoelectric generators (TEGs) capable of adopting any form or shape with enhanced thermoelectric properties. These green TEGs are meant to compete with common toxic materials such as Bi2Te3, PbTe and CoSb that have Seebeck coefficients in the range of ~ 290–700 μV/K, similar to that of the produced Mg2Si powders and lower than that of 3D printed bulk Mg2Si pieces, measured to be ~ 4866 μV/K. Also, their measured thermal conductivities proved to be significantly lower (~ 0.2 W/mK) than that reported for Mg2Si (≥ 4 W/mK). However, it is herein demonstrated that such thermoelectric properties are not stable over time. Pressureless sintering proved to be indispensable, but difficultly achievable by long thermal annealing (even above 32 h) in inert atmosphere at 400 °C, at least for bulk Mg2Si pieces constituted by a mean grain size of 2–3 μm. Hence, for overcoming this sintering challenge and become the silicide’s extrusion viable in the production of bulk thermoelectric parts, alternative pressureless sintering methods will have to be further explored.

Third-generation electrochemical biosensor based on nitric oxide reductase immobilized in a multiwalled carbon nanotubes/1-n-butyl-3-methylimidazolium tetrafluoroborate nanocomposite for nitric oxide detection - Gomes, FO; Maia, L. B.; Delerue-Matos, C.; Moura, I.; Moura, J. J. G.; Morais, S. (Sensors & Actuators: B. Chemical, 2019)

A top-down chemo-enzymatic approach towards N-acetylglucosamine-N-acetylmuramic oligosaccharides: Chitosan as a reliable template - Queda, Fausto; Covas, Gonçalo; Silva, Tomé; Santos, Cátia Almeida; Bronze, Maria R.; Cañada, Francisco Javier; Corvo, Marta C.; Filipe, Sérgio R; Marques, M. Manuel B. (Carbohydrate Polymers, 2019)
An unprecedented approach towards oligosaccharides containing N-acetylglucosamine-N-acetylmuramic (NAG-NAM) units was developed. These novel bacterial cell wall surrogates were obtained from chitosan via a top down approach involving both chemical and enzymatic reactions. The chemical modification of chitosan using a molecular clamp based strategy, allowed obtaining N-acetylglucosamine-N-acetylmuramic (NAG-NAM) containing oligomers. Intercalation of NAM residues was confirmed through the analysis of oligosaccharide fragments from enzymatic digestion and it was found that this route affords NAG-NAM containing oligosaccharides in 33% yield. These oligosaccharides mimic the carbohydrate basic skeleton of most bacterial cell surfaces. The oligosaccharides prepared are biologically relevant and will serve as a platform for further molecular recognition studies with different receptors and enzymes of both bacterial cell wall and innate immune system. This strategy combining both chemical modification and enzymatic digestion provides a novel and simple route for an easy access to bacterial cell wall fragments – biologically important targets.
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A top-down chemo-enzymatic approach towards N-acetylglucosamine-N-acetylmuramic oligosaccharides: chitosan as a reliable template - F. Queda; G. Covas; Silva, T; Santos, C A; Bronze, M R; Canada, F J; Corvo, Mc; S. R. Filipe*; Marques*, M M B (Carbohydrate Polymers, 2019)

The treta copper-sulfide center of nitrous oxide reductase - Pauleta, S. R.; Carepo, M. S.; Moura, I. (Transition Metals and Sulfur- A Strong Relationship with Life, 2019)

Using water to control electrospun Polycaprolactone fibre morphology for soft tissue engineering - Susana Gomes; Diana Querido; José Luís Ferreira; Borges, João Borges; Célia Henriques; Silva, Jorge Carvalho (Journal of Polymer Research, 2019)
Control of the properties of electrospun polycaprolactone can be achieved by adjusting the acetic acid:water ratio used to dissolve and electrospin the polymer. In this work, we studied the effect of using up to 15 wt% water in the solvent mixture. Solution conductivity and viscosity and fibre morphology vary dramatically with water content and solution age. Two days after initial solution preparation, electrospinning yields regular fibres for a water content of 0 wt% and 5 wt%, irregular fibres for a 10 wt% water content and irregular and fused fibres for a 15 wt% water content. Fibres with the highest crystallinity (60%) were obtained from solutions containing 5 wt% water while the highest elastic modulus (8.6 ± 1.4 MPa) and tensile stress (4.3 ± 0.3 MPa) pertain to fibres obtained from solutions containing 10 wt% water. Enzymatic fibre degradation is faster the higher the water content in the precursor solution. Adhesion ratio of human foetal fibroblasts was highest on scaffolds obtained from precursor solutions containing 0 wt% water. Cell population increases for all scaffolds and populations quickly become equivalent, with no statistically significant differences between them. Cells exhibit a more extended morphology on the 5 wt% scaffold and a more compact morphology on the 0 wt% scaffold. In summary, a small water content in the solvent allows a significant control over fibre diameter, scaffold properties and the production of scaffolds that support cell adhesion and proliferation. This strategy can be used in soft tissue engineering to influence cell behaviour and the degradation rate of the scaffolds.

β-Hairpins as peptidomimetics of human phosphoprotein-binding domains - Batalha, IL; Lychko, I; Branco, R. J. F.; Iranzo, O.; Roque, A. C. A. (Organic & Biomolecular Chemistry, 2019)
Phosphoprotein-binding domains interact with cognate phosphorylated targets ruling several biological processes. The impairment of such interactions is often associated with disease development, namely cancer. The breast cancer susceptibility gene 1 (BRCA1) C-terminal (BRCT) domain is involved in the control of complex signaling networks of the DNA damage response. The capture and identification of BRCT-binding proteins and peptides may be used for the development of new diagnostic tools for diseases with abnormal phosphorylation profiles. Here we show that designed cyclic β-hairpin structures can be used as peptidomimetics of the BRCT domain, with high selectivity in binding to a target phosphorylated peptide. The amino acid residues and spatial constraints involved in the interaction between a phosphorylated peptide (GK14-P) and the BRCT domain were identified and crafted onto a 14-mer β-hairpin template in silico. Several cyclic peptides models were designed and their binding towards the target peptide and other phosphorylated peptides evaluated through virtual screening. Selected cyclic peptides were then synthesized, purified and characterized. The high affinity and selectivity of the lead cyclic peptide towards the target phosphopeptide was confirmed, and the possibility to capture it using affinity chromatography demonstrated. This work paves the way for the development of cyclic β-hairpin peptidomimetics as a novel class of affinity reagents for the highly selective identification and capture of target molecules.

2D Resistive Switching Based on Amorphous Zinc–Tin Oxide Schottky Diodes - CasaBranca, N.; Deuermeier, J.; Martins, J.; Carlos, E.; Pereira, M.; R. Martins; E. Fortunato; Kiazadeh, A. (Advanced Electronic Materials, 2019)
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All-Thin-Film Perovskite/C–Si Four-Terminal Tandems: Interlayer and Intermediate Contacts Optimization - Chapa, Manuel; Alexandre, Miguel F.; Mendes, Manuel J.; Hugo Águas; Elvira Fortunato; Rodrigo Martins (ACS Applied Energy Materials, 2019)
Combined perovskite/crystalline-silicon four-terminal tandem solar cells promise >30% efficiencies. Here we propose all-thin-film double-junction architectures where high-bandgap perovskite top cells are coupled to ultrathin c-Si bottom cells enhanced with light trapping. A complete optoelectronic model of the devices was developed and applied to determine the optimal intermediate layers, which are paramount to maximize the cells’ photocurrent. It was ascertained that by replacing the transparent conductive oxides by grid-based metallic contacts in the intermediate positions, the parasitic absorption is lowered by 30%. Overall, a 29.2% efficiency is determined for ∼2 um thick tandems composed of the optimized interlayers and improved with Lambertian light trapping.
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Biofilm development and computational screening for new putative inhibitors of a homolog of the regulatory protein BrpA in Streptococcus dysgalactiae subsp. dysgalactiae - Alves-Barroco, Cinthia; Catarina Roma-Rodrigues; Natesan Balasubramanian; Aparecida Guimarães, Marcia; Bernadete T. Ferreira-Carvalho; Muthukumaran, Jayaraman; Nunes, Daniela; Elvira Fortunato; Rodrigo Martins; Santos-Silva, Teresa; Agnes M.S. Figueiredo; Alexandra R. Fernandes; et al. (International Journal of Medical Microbiology, 2019)
Streptococcus dysgalactiae subsp. dysgalactiae (SDSD), a Lancefield group C streptococci (GCS), is a frequent cause of bovine mastitis. This highly prevalent disease is the costliest in dairy industry. Adherence and biofilm production are important factors in streptoccocal pathogenesis. We have previously described the adhesion and internalization of SDSD isolates in human cells and now we describe the biofilm production capability of this bacterium. In this work we integrated microbiology, imaging and computational methods to evaluate the biofilm production capability of SDSD isolates; to assess the presence of biofilm regulatory protein BrpA homolog in the biofilm producers; and to predict a structural model of BrpA-like protein and its binding to putative inhibitors. Our results show that SDSD isolates form biofilms on abiotic surface such as glass (hydrophilic) and polystyrene (hydrophobic), with the strongest biofilm formation observed in glass. This ability was mainly associated with a proteinaceous extracellular matrix, confirmed by the dispersion of the biofilms after proteinase K and trypsin treatment. The biofilm formation in SDSD isolates was also confirmed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Under SEM observation, VSD16 isolate formed cell aggregates during biofilm growth while VSD9 and VSD10 formed smooth and filmy layers. We show that brpA-like gene is present and expressed in SDSD biofilm-producing isolates and its expression levels correlated with the biofilm production capability, being more expressed in the late exponential phase of planktonic growth compared to biofilm growth. Fisetin, a known biofilm inhibitor and a putative BrpA binding molecule, dramatically inhibited biofilm formation by the SDSD isolates but did not affect planktonic growth, at the tested concentrations. Homology modeling was used to predict the 3D structure of BrpA-like protein. Using high throughput virtual screening and molecular docking, we selected five ligand molecules with strong binding affinity to the hydrophobic cleft of the protein, making them potential inhibitor candidates of the SDSD BrpA-like protein. These results warrant further investigations for developing novel strategies for SDSD anti-biofilm therapy.
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Keywords: Biofilm; Biofilm regulatory protein; BrpA inhibitors; Molecular docking; subsp.

Biomethane production through anaerobic co-digestion with Maize Cob Waste based on a biorefinery concept: A review - Elena Surra; Bernardo, Maria; Nuno Lapa; Isabel A.A.C. Esteves; Fonseca, Isabel; José P.B. Mota (Journal of Environmental Management, 2019)
Maize Cob Waste (MCW) is available worldwide in high amounts, as maize is the most produced cereal in the world. MCW is generally left in the crop fields, but due to its low biodegradability it has a negligible impact in soil fertility. Moreover, MCW can be used as substrate to balance the C/N ratio during the Anaerobic co-Digestion (AcoD) with other biodegradable substrates, and is an excellent precursor for the production of Activated Carbons (ACs). In this context, a biorefinery is theoretically discussed in the present review, based on the idea that MCW, after proper pre-treatment is valorised as precursor of ACs and as co-substrate in AcoD for biomethane generation. This paper provides an overview on different scientific and technological aspects that can be involved in the development of the proposed biorefinery; the major topics considered in this work are the following ones: (i) the most suitable pre-treatments of MCW prior to AcoD; (ii) AcoD process with regard to the critical parameters resulting from MCW pre-treatments; (iii) production of ACs using MCW as precursor, with the aim to use these ACs in biogas conditioning (H2S removal) and upgrading (biomethane production), and (iv) an overview on biogas upgrading technologies.
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Keywords: Activated carbon; Anaerobic co-digestion; Bio-methane; Biorefinery; Maize Cob Waste; Pre-treatments

Char from Spent Tire Rubber: A Potential Adsorbent of Remazol Yellow Dye - Nogueira, Miguel; Matos, Inês; Bernardo, Maria; Filomena Pinto; Nuno Lapa; Elena Surra; Fonseca, Isabel (C—Journal of Carbon Research, 2019)
A char produced from spent tire rubber showed very promising results as an adsorbent of Remazol Yellow (RY) from aqueous solutions. Spent tire rubber was submitted to a pyrolysis process optimized for char production. The obtained char was submitted to chemical, physical, and textural characterizations and, subsequently, applied as a low-cost adsorbent for dye (RY) removal in batch adsorption assays. The obtained char was characterized by relatively high ash content (12.9% wt), high fixed-carbon content (69.7% wt), a surface area of 69 m2/g, and total pore volume of 0.14 cm3/g. Remazol Yellow kinetic assays and modelling of the experimental data using the pseudo-first and pseudo-second order kinetic models demonstrated a better adjustment to the pseudo-first order model with a calculated uptake capacity of 14.2 mg RY/g char. From the equilibrium assays, the adsorption isotherm was fitted to both Langmuir and Freundlich models; it was found a better fit for the Langmuir model to the experimental data, indicating a monolayer adsorption process with a monolayer uptake capacity of 11.9 mg RY/g char. Under the experimental conditions of the adsorption assays, the char presented positive charges at its surface, able to attract the deprotonated sulfonate groups (SO3−) of RY; therefore, electrostatic attraction was considered the most plausible mechanism for dye removal.
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Colloidal-structured metallic micro-grids: High performance transparent electrodes in the red and infrared range - Giacomo Torrisi; João S. Luis; Sanchez-Sobrado, Olalla; Rosario Raciti; Mendes, Manuel J.; Hugo Águas; Elvira Fortunato; Rodrigo Martins; Antonio Terrasi (Solar Energy Materials and Solar Cells, 2019)
One of the most promising approaches to produce industrial-compatible Transparent Conducting Materials (TCMs) with excellent characteristics is the fabrication of TCO/metal/TCO multilayers. In this article, we report on the electro-optical properties of a novel high-performing TCO/metal/TCO structure in which the intra-layer is a micro-structured metallic grid instead of a continuous thin film. The grid is obtained by evaporation of Ag through a mask of polystyrene colloidal micro-spheres deposited by the Langmuir-Blodgett method and partially dry-etched in plasma. IZO/Ag grid/IZO structures with different thicknesses and mesh dimensions have been fabricated, exhibiting excellent electrical characteristics (sheet resistance below 10 Ω/□) and particularly high optical transmittance in the near-infrared spectral region as compared to planar (unstructured) TCM multilayers. Numerical simulations were also used to highlight the role of the Ag mesh parameters on the electrical properties.
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Keywords: Ag micro-grid; IR trasmittance; Multilayer thin film; Transparent conductive electrodes

Counteracting the effect of leukemia exosomes by antiangiogenic gold nanoparticles - Catarina Roma-Rodrigues; Fernandes, Alexandra R; Baptista, Pedro V (International journal of nanomedicine, 2019)
Purpose: Progression of chronic myeloid leukemia (CML) is frequently associated with increased angiogenesis at the bone marrow mediated by exosomes. The capability of gold nanoparticles (AuNPs) functionalized with antiangiogenic peptides to hinder the formation of new blood vessels has been demonstrated in a chorioallantoic membrane (CAM) model. Methods: Exosomes of K562 CML cell line were isolated and their angiogenic effect assessed in a CAM model. AuNPs functionalized with antiangiogenic peptides were used to block the angiogenic effect of CML-derived exosomes, assessed by evaluation of expression levels of key modulators involved in angiogenic pathways - VEGFA, VEGFR1 (also known as FLT1) and IL8. Results: Exosomes isolated from K562 cells promoted the doubling of newly formed vessels associated with the increase of VEGFR1 expression. This is a concentration and timedependent effect. The AuNPs functionalized with antiangiogenic peptides were capable to block the angiogenic effect by modulating VEGFR1 associated pathway. Conclusion: Exosomes derived from blast cells are capable to trigger (neo)-angiogenesis, a key factor for the progression and spreading of cancer, in particular in CML. AuNPs functionalized with specific antiangiogenic peptides are capable to block the effect of the exosomes produced by malignant cells via modulation of the intrinsic VEGFR pathway. Together, these data highlight the potential of nanomedicine-based strategies against cancer proliferation.
FCT/MCTES - UID/Multi/04378/2019. FCT/MCTES - SFRH/BPD/124612/2016.
Keywords: angiogenesis; chorioallantoic membrane; chronic myeloid leukemia; Exosomes; Gold nanoparticles

Crystal habit modification and polymorphic stability assessment of a long-acting β2-adrenergic agonist - Tulcidas, Ameessa; Lourenço, Nuno M. T.; Antunes, Rafael; Santos, Bruno; Sylwin Pawlowski; Rocha, Fernando (CrystEngComm, 2019)
Properties such as particle orientation{,} flowability{,} packing{,} compaction{,} syringeability{,} suspension stability and dissolution are the most influenced by changes in the crystal habit and polymorphic form of a drug substance. The crystal habit of a drug substance (long-acting β2-adrenergic agonist (LABA)){,} as well as its purity and polymorphic stability{,} was studied after performing slurry tests with 1{,}2-dimethoxyethane : heptane solution at 50 °C. In these slurry tests{,} the product was kept suspended and undissolved{,} with agitation{,} for polymorphic conversion evaluation. Since no significant modifications were observed in the crystal shape and dimensions at 50 °C{,} a new slurry test was performed at a temperature above the melting point of the starting material (80 °C). In the latter test{,} it was possible to obtain crystals with increased dimensions by 480% compared with the starting material. Additionally{,} the desired polymorphic form (form I) was obtained as well as an acceptable purity of approximately 99%. These are promising results{,} not only for downstream purposes{,} but also concerning the bioavailability of the drug substance. This work shows that working at a temperature higher than the melting point of the compound seems to modify the crystal habit of the product.
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Electrochemical metallization ReRAMs (ECM) - Experiments and modelling: General discussion - Ambrosi, E.; Bartlett, P.; Berg, A.I.; Brivio, S.; Burr, G.; Deswal, S.; Deuermeier, J.; Haga, M.-A.; Kiazadeh, A.; Kissling, G.; Kozicki, M.; Foroutan-Nejad, C.; et al. (Faraday Discussions, 2019)
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Evaluation of the adsorption potential of biochars prepared from forest and agri-food wastes for the removal of fluoxetine - Maria João Fernandes; Manuela M. Moreira; Paula Paíga; Diogo Dias; Bernardo, Maria; Manuela Carvalho; Nuno Lapa; Fonseca, Isabel; Simone Morais; Sónia Figueiredo; Cristina Delerue-Matos (Bioresource Technology, 2019)
Twelve biochars from forest and agri-food wastes (pruning of Quercus ilex, Eucalyptus grandis, Pinus pinaster, Quercus suber, Malus pumila, Prunus spinosa, Cydonia oblonga, Eriobotrya japonica, Juglans regia, Actinidia deliciosa, Citrus sinensis and Vitis vinifera) were investigated as potential low-cost and renewable adsorbents for removal of a commonly used pharmaceutical, fluoxetine. Preliminary adsorption experiments allowed to select the most promising adsorbents, Quercus ilex, Cydonia oblonga, Eucalyptus, Juglans regia and Vitis vinifera pruning material. They were characterized by proximate, elemental and mineral analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy, determination of specific surface area and pH at the point of zero charge. Batch and equilibrium studies were performed, and the influence of pH was evaluated. The equilibrium was reached in less than 15 min in all systems. The maximum adsorption capacity obtained was 6.41 mg/g for the Eucalyptus biochar, which also demonstrated a good behavior in continuous mode (packed column).
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Keywords: Anti-depressant pharmaceutical; Biochar; Column experiments; Kinetics and equilibrium; Waste valorization

Fungal biodeterioration of stained-glass windows in monuments from Belém do Pará (Brazil) - A.M. Corrêa Pinto; Palomar, T.; L.C. Alves; S.H.M. da Silva; R.C. Monteiro; Macedo, MF; M.G. Vilarigues (International Biodeterioration & Biodegradation, 2019)
The most prominent historical buildings in Belém do Pará (Northern Brazil) have modernist stained-glass windows, which were commissioned from Europe since the end of the 19th century. Some of them present biodegradation; however, there is no information about the microbial activity on them. The present work is focused on the biodeterioration by fungi on some of these Modern stained-glass windows. The fungal communities were collected, isolated and then identified by means of molecular methods. Additionally, a laboratory-based biodeterioration experiment was carried out to assess the fungal activity on replica glass samples with three different chemical compositions. The replica samples were inoculated with a four-fungal species mixture and incubated under optimal growth conditions for 5 months. Optical microscopy, μ-PIXE, SEM-EDS and FTIR-ATR were performed to evaluate the biodeterioration of the soda-lime silicate glasses. This multidisciplinary approach showed that the inoculated spores (Aspergillus arenarioides, Fusarium oxysporum, Hortaea werneckii, and Trichoderma longibrachiatum) were able to form substantial mycelia in all replica glass samples. The main alterations observed were small crystals, hyphae fingerprints and a slight decrease on the glass surface smoothness. Despite the aforementioned damages, the soda-lime silicate glass compositions showed high resistance against the inoculated fungal species.
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Keywords: Biodeterioration; Fungal identification; Stained-glass windows; Tropical climate

Glycerol conversion into biofuel additives by acetalization with pentanal over heteropolyacids immobilized on zeolites - Castanheiro, J. E.; Vital, J.; I. M. Fonseca; A. M. Ramos (Catalysis Today, 2019)
Dodecamolydbophosphoric acid (HPMo) immobilized on USY zeolite was used as a catalyst for the acetalization of glycerol with pentanal at 70 °C. Catalysts were prepared with different amounts of heteropolyacid, and the most active sample was the HPMo2@Y catalyst (1.1 wt.%). The products of glycerol acetalization with pentanal were (2-butyl-1,3-dioxolan-4-yl)methanol, a five-member ring compound, and 2-butyl-1,3-dioxan-5-ol, a six-member ring compound. Good values of selectivity for the five-member ring compound (80–85%) were obtained with all materials. The reaction conditions were optimized using HPMo2@Y as a catalyst. The optimal conditions were determined to be 70 °C reaction temperature with 0.3 g catalyst and a 1:2.5 M ratio of glycerol to pentanal. The catalytic stability of HPMo2@Y was studied. The acetalization of glycerol with pentanal was performed using the same sample. High catalytic activity for HPMo2@Y was observed.
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Keywords: Acetalization; Glycerol; Green processes; Heterogeneous catalysis; Heteropolyacids

Human aldehyde oxidase (hAOX1): structure determination of the Moco-free form of the natural variant G1269R and biophysical studies of single nucleotide polymorphisms - Mota, Cristiano; Esmaeeli, Mariam; Coelho, Catarina; Santos-Silva, Teresa; Wolff, Martin; Foti, Alessandro; Leimkühler, Silke; Romão, Maria João (FEBS Open Bio, 2019)
Human aldehyde oxidase (hAOX1) is a molybdenum enzyme with high toxicological importance, but its physiological role is still unknown. hAOX1 metabolizes different classes of xenobiotics and is one of the main drug-metabolizing enzymes in the liver, along with cytochrome P450. hAOX1 oxidizes and inactivates a large number of drug molecules and has been responsible for the failure of several phase I clinical trials. The interindividual variability of drug-metabolizing enzymes caused by single nucleotide polymorphisms (SNPs) is highly relevant in pharmaceutical treatments. In this study, we present the crystal structure of the inactive variant G1269R, revealing the first structure of a molybdenum cofactor (Moco)-free form of hAOX1. These data allowed to model, for the first time, the flexible Gate 1 that controls access to the active site. Furthermore, we inspected the thermostability of wild-type hAOX1 and hAOX1 with various SNPs (L438V, R1231H, G1269R or S1271L) by CD spectroscopy and ThermoFAD, revealing that amino acid exchanges close to the Moco site can impact protein stability up to 10 °C. These results correlated with biochemical and structural data and enhance our understanding of hAOX1 and the effect of SNPs in the gene encoding this enzyme in the human population. Enzymes Aldehyde oxidase (EC1.2.3.1); xanthine dehydrogenase (EC1.17.1.4); xanthine oxidase (EC1.1.3.2). Databases Structural data are available in the Protein Data Bank under the accession number 6Q6Q.
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Keywords: human aldehyde oxidase; molybdenum cofactor; single nucleotide polymorphism; Xanthine Oxidase

Lightwave trapping in thin film solar cells with improved photonic-structured front contacts - Sanchez-Sobrado, Olalla; Mendes, Manuel J.; Haque, Sirazul; Mateus, Tiago; Hugo Aguas; Elvira Fortunato; Rodrigo Martins (J. Mater. Chem. C, 2019)
Photonic microstructures placed at the topside of photovoltaic cells are currently one of the preferred light management solutions to obtain efficiency enhancement due to the increment of the optical absorption produced in the active medium of the devices. Herein{,} we present the results concerning a practical{,} low-cost and scalable approach to integrate metal-oxide based light trapping microstructures on the front contact of amorphous silicon thin film solar cells. A colloidal lithography method was used to pattern the wavelength-sized pyramidal-like features composing the structures{,} made of two different transparent materials{,} TiO2 and IZO{,} allowing the detailed study of the influence of their geometrical parameters on the optoelectronic properties of the devices. These top coating structures are deposited as a post-process after the solar cell fabrication{,} thus facilitating and broadening their industrial applicability. Measurements of the light absorption{,} external quantum efficiency and I–V curves revealed that the structured coatings provide strong broadband improvements in the generated current{,} due to the suppression of reflected light at short wavelengths and the increment of the optical path length of the longer wavelengths (via light scattering){,} within the amorphous silicon layer. As a result{,} in the four types of structures analyzed in this study{,} remarkable increments were achieved in the cells’ efficiencies (up to 14.4%) and generated currents (up to 21.5%){,} with respect to the flat reference cells.
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Liquid biopsies in myeloid malignancies - Abdulmawjood, Bilal R.; Catarina Roma-Rodrigues; Fernandes, Alexandra R; Baptista, Pedro V (Cancer Drug Resistance, 2019)
Hematologic malignancies are the most common type of cancer affecting children and young adults, and encompass diseases, such as leukemia, lymphoma, and myeloma, all of which impact blood associated tissues such as the bone marrow, lymphatic system, and blood cells. Clinical diagnostics of these malignancies relies heavily on the use of bone marrow samples, which is painful, debilitating, and not free from risks for leukemia patients. Liquid biopsies are based on minimally invasive assessment of markers in the blood (and other fluids) and have the potential to improve the efficacy of diagnostic/therapeutic strategies in leukemia patients, providing a useful tool for the real time molecular profiling of patients. The most promising noninvasive biomarkers are circulating tumor cells, circulating tumor DNA, microRNAs, and exosomes. Herein, we discuss the role of assessing these circulating biomarkers for the understanding of tumor progression and metastasis, tumor progression dynamics through treatment and for follow-up.
info:eu-repo/grantAgreement/FCT/6817 - DCRRNI ID/UID%2FMulti%2F04378%2F2019/PT#
Keywords: circulating tumor cells; circulating tumor DNA; Exosomes; leukemia; Liquid biopsy; microRNAs

Multi-level cell properties of a bilayer Cu2O/Al2O3 resistive switching device - Deuermeier, J.; Kiazadeh, A.; Klein, A.; R. Martins; E. Fortunato (Nanomaterials, 2019)
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cited By 0

New adsorbents from maize cob wastes and anaerobic digestate for H2S removal from biogas - Elena Surra; Miguel Costa Nogueira; Bernardo, Maria; Nuno Lapa; Isabel Esteves; Fonseca, Isabel (Waste Management, 2019)
Two activated carbons (ACs) were prepared by physical activation of Maize Cob Waste (MCW) with CO2, during 2 and 3 h (MCW(PA)2h and MCW(PA)3h, respectively). Two other ACs were prepared by chemical activation: a) MCW(LD) – MCW was impregnated with anaerobic liquid digestate (LD) and carbonized under N2 atmosphere; and b) CAR-MCW(LD) – previously carbonized MCW was impregnated with LD and carbonized under N2 atmosphere. All ACs were fully characterized for textural and chemical properties, and then used in dynamic H2S removal assays from real biogas samples. Regarding H2S removal, the ACs that were physically activated behaved much better than the impregnated ones: MCW(PA)3h and MCW(PA)2h showed H2S uptake capacities of 15.5 and 0.65 mg g−1, respectively, while MCW(LD) and CAR-MCW(LD) showed values of 0.47 and 0.25 mg g−1, respectively. This may indicate that textural properties (surface area and microporosity) are more important than mineral content in H2S removal. Effectively, both surface area and micropore volume were much higher for the samples of MCW(PA)3h (SBET = 820 m2 g−1 and Vmicro = 0.32 cm3 g−1) and MCW(PA)2h (SBET = 630 m2 g−1 and Vmicro = 0.21 cm3 g−1) than for the ACs that were chemically activated (SBET = 38.0 m2 g−1 and Vmicro = 0.01 cm3 g−1 for MCW(LD); SBET = 8.0 m2 g−1 and Vmicro = 0.01 cm3 g−1 for CAR-MCW(LD)). High oxygen content in MCW(PA)3h favoured the catalytic oxidation reaction of H2S, promoting its removal. The use of MCW as precursor and LD as activating agent of the ACs may contribute for the integrated management of maize wastes and to diversify the applications of anaerobic digestate.
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Keywords: activated carbons; Anaerobic digestate; Biogas; HS removal; Maize Cob Waste

New and Advanced Porous Carbon Materials in Fine Chemical Synthesis. Emerging Precursors of Porous Carbons - Pérez-Mayoral, Elena; Matos, Inês; Bernardo, Maria; Fonseca, Isabel M. (Catalysts, 2019)
The efficiency of porous carbons in fine chemical synthesis, among other application fields, has been demonstrated since both the porous structure and chemical surface provide the appropriated chemical environment favoring a great variety of relevant chemical transformations. In recent years, metal organic frameworks (MOFs) and covalent organic frameworks (COFs) have emerged as interesting opportunities in the preparation of porous carbons with improved physico-chemical properties. Direct calcination of MOFs or COFs, in the presence or not of others carbon or heteroatom sources, could be considered an easy and practical approach for the synthesis of highly dispersed heteroatom-doped porous carbons but also new porous carbons in which single atoms of metallic species are present, showing a great development of the porosity; both characteristics of supreme importance for catalytic applications. The goal of this review is to provide an overview of the traditional methodologies for the synthesis of new porous carbon structures together with emerging ones that use MOFs or COFs as carbon precursors. As mentioned below, the catalytic application in fine chemical synthesis of these kinds of materials is at present barely explored, but probably will expand in the near future.
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Optimum Luminescent Down-Shifting Properties for High Efficiency and Stable Perovskite Solar Cells - Alexandre, Miguel; Chapa, Manuel; Haque, Sirazul; Mendes, Manuel J.; Hugo Águas; Elvira Fortunato; Rodrigo Martins (ACS Applied Energy Materials, 2019)
In recent years, the discovery of the excellent optical and electrical properties of perovskite solar cells (PSCs) made them a main focus of research in photovoltaics, with efficiency records increasing astonishingly fast since their inception. However, problems associated with the stability of these devices are hindering their market application. UV degradation is one of the most severe issues, chiefly caused by TiO2’s photogenerated electrons that decompose the perovskite absorber material, coupled with the additional intrinsic degradation of this material under UV exposure. The solution presented here can minimize this effect while boosting the cells’ generated photocurrent, by making use of combined light-trapping and luminescent down-shifting effects capable of changing the harmful UV radiation to higher wavelengths that do not affect the stability and can be effectively “trapped” in the cell. This work focuses in the optimization of the photocurrent gains that can be attained by emulating the changed spectrum resulting from applying down-shifting media as encapsulant in photonic-enhanced PSCs, as well as the reduction in the harmful effects of UV radiation on the devices. Such optimized photonic solution allows current enhancement while reducing the harmful UV photocarrier generation both in the TiO2 (by 1 order of magnitude) and in the perovskite (by 80%) relative to a standard PSC without light management.
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Photonic-structured TiO2 for high-efficiency, flexible and stable Perovskite solar cells - Haque, Sirazul; Mendes, Manuel J.; Sanchez-Sobrado, Olalla; Hugo Águas; Elvira Fortunato; Rodrigo Martins (Nano Energy, 2019)
Optical solutions are promising for Perovskite solar cell (PSC) technology, not only to increase efficiency, but also to allow thinner absorber layers (higher flexibility) and improve stability. This work optimized the combined anti-reflection and scattering properties of two types of light trapping (LT) structures, based on TiO2 semi-spheroidal geometries with honeycomb periodicity, for application in PSCs with substrate configuration and different perovskite layer thicknesses. Their optically lossless material (TiO2) allows the structures to be patterned in the final processing steps, integrated in the cells’ top n contact, therefore not increasing the surface area of the PV layers and not degrading the electric performance via recombination. Therefore, this strategy circumvents the typical compromise of state-of-the-art LT approaches between optical improvements and electrical deterioration, which is particularly relevant for PSCs since their main recombination is caused by surface defects. When patterned on the cells’ front, the wave-optical micro-features composing the LT structures yield up to 21% and 27% photocurrent enhancement in PSCs with conventional (500 nm thick) and ultra-thin (250 nm) perovskite layers, respectively; which are improvements close to those predicted by theoretical Lambertian limits. In addition, such features are shown to provide an important encapsulation role, preventing the cells’ degradation from UV penetration.
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Keywords: Light trapping; Perovskite solar cells; Photonics; Photovoltaics; UV stability improvement

Plasmonic nanostructures for light trapping in thin-film solar cells - S. Morawiec; M. J. Mendes; F. Priolo; I. Crupi (Materials Science in Semiconductor Processing, 2019)
The optical properties of localized surface plasmon resonances (LSPR) sustained by self-assembled silver nanoparticles are of great interest for enhancing light trapping in thin film photovoltaics. First, we report on a systematic investigation of the structural and the optical properties of silver nanostructures fabricated by a solid-state dewetting process on various substrates. Our study allows to identify fabrication conditions in which circular, uniformly spaced nanoparticles are obtainable. The optimized NPs are then integrated into plasmonic back reflector (PBR) structures. Second, we demonstrate a novel procedure, involving a combination of opto-electronic spectroscopic techniques, allowing for the quantification of useful and parasitic absorption in thin photovoltaic absorber deposited on top of the PBR. We achieve a significant broadband useful absorption enhancement of 90% for 0.9 µm thick μc-Si:H film and demonstrate that optical losses due to plasmonic scattering are insignificant below 730 nm. Finally, we present a successful implementation of a plasmonic light trapping scheme in a thin film a-Si:H solar cell. The quantum efficiency spectra of the devices show a pronounced broadband enhancement resulting in remarkably high short circuit current densities (Jsc).
Material processing of optical devices and their applications
Keywords: Localized surface plasmon resonance; nanoparticles; Photovoltaics; Plasmonic-enhanced light trapping; self-assembly; Subwavelength nanostructures; Thin film solar cells

Porous carbons-derived from vegetal biomass in the synthesis of quinoxalines. Mechanistic insights - M. Godino-Ojer; R. Blazquez-García; Matos, I.; M. Bernardo; I. M. Fonseca; E. Pérez Mayoral (Catalysis Today, 2019)
We report herein for the first-time acid biomass-derived carbons from vegetal biomass, with high developed porosity, prepared through integrating method comprising pyrolysis and surface phosphonation, able to efficiently catalyze the synthesis of quinoxalines from 1,2-diamines and α-hydroxi ketones, under aerobic conditions. The obtained results indicate that the reaction is mainly driven by a combination of acid function strength and textural properties in terms of conversion and selectivity. Furthermore, our experimental and theoretical observations suggest that the preferred reaction pathway for this transformation, in the presence of the investigated acid carbon catalysts, involves cascade reactions including imination reaction between reactants, successive imine-enamine and keto-enol tautomerisms, heterocyclization followed by dehydration, and aromatization. While the acid sites seem to be a relevant role in each reaction step, the system formed by activated carbon and molecular oxygen could be behind the last oxidative reaction to give the corresponding nitrogen heterocycles.
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Keywords: Computational methods; Fine chemicals; Nanocatalysts; Porous carbons; Quinoxalines

Principles of Nuclear Magnetic Resonance and Selected Biological Applications - Salgueiro, , Carlos A.; Joana M Dantas; Leonor Morgado (Radiation in Bioanalysis: Spectroscopic Techniques and Theoretical Methods, 2019)
Nuclear Magnetic Resonance (NMR) spectroscopy is extremely powerful to study distinct biological systems ranging from biomolecules to specific metabolites. This chapter presents the basic concepts of the technique and illustrates its potential to study such systems. Similarly, to other spectroscopic techniques, the theoretical background of NMR is sustained by detailed mathematics and physical chemistry concepts, which were kept to the minimum. The intent is to introduce the fundamentals of the technique to science students from different backgrounds. The basic concepts of NMR spectroscopy are briefly presented in the first section, and the following sections describe applications in the biosciences field, using electron transfer proteins as model, particularly cytochromes. The heme groups endow cytochromes with particular features making them excellent examples to illustrate the high versatility of NMR spectroscopy. The main methodologies underlying protein solution structure determination are discussed in the second section. This is followed by a description of the main experiments explored to structurally map protein-protein or protein-ligand interface regions in molecular complexes. Finally, it is shown how NMR spectroscopy can assist in the functional characterization of multiheme cytochromes.
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Profiled Ion Exchange Membranes: A Comprehensible Review - Sylwin Pawlowski; João G. Crespo; Velizarov, Svetlozar (International Journal of Molecular Sciences, 2019)
Profiled membranes (also known as corrugated membranes, micro-structured membranes, patterned membranes, membranes with designed topography or notched membranes) are gaining increasing academic and industrial attention and recognition as a viable alternative to flat membranes. So far, profiled ion exchange membranes have shown to significantly improve the performance of reverse electrodialysis (RED), and particularly, electrodialysis (ED) by eliminating the spacer shadow effect and by inducing hydrodynamic changes, leading to ion transport rate enhancement. The beneficial effects of profiled ion exchange membranes are strongly dependent on the shape of their profiles (corrugations/patterns) as well as on the flow rate and salts’ concentration in the feed streams. The enormous degree of freedom to create new profile geometries offers an exciting opportunity to improve even more their performance. Additionally, the advent of new manufacturing methods in the membrane field, such as 3D printing, is anticipated to allow a faster and an easier way to create profiled membranes with different and complex geometries.
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Quality by Statistical Control in Crystallization—Assessment of Mixing Conditions and Probability of Obtaining the Desired Particle Size - Tulcidas, Ameessa; Santos, Bruno; Sylwin Pawlowski; Rocha, Fernando (Industrial & Engineering Chemistry Research, 2019)
Reactor hydrodynamics can play a significant role in antisolvent crystallizations. In this work, the impact of suspension height/clearance ratio (H/C) and power per volume (PV) on the particle size distribution (PSD) parameters Dv10, Dv50, and Dv90 of an active pharmaceutical ingredient (API) were evaluated. The API solution was added near the liquid surface of the antisolvent with a buret, at a rate of approximately 5 mL/min, between the impeller and the reactor’s wall. Statistical models were developed, and it was found that PSD parameters seem to be influenced by the H/C and PV. A relationship between the PSD parameters and the nucleation rate was also witnessed. Furthermore, different mathematical methodologies (indicator function and Monte Carlo simulations) were used to obtain a design space comprising the probability of success of having PSD parameters within specification. An operating region comprising the probability of success was estimated, which can aid in minimizing the risk of failure in antisolvent crystallization processes and consequently help reduce the financial losses caused by out-of-specification batches.
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Resistance to Aminoglycosides - Correia, Viviana G.; Pinheiro, Benedita A.; Ana Luísa Carvalho; Palma, Angelina S. (Antibiotic Drug Resistance, 2019)
Summary The emergence of bacterial resistance to different antibiotics in clinical use, together with the knowledge on the mechanisms by which bacteria resist the action of aminoglycosides, have contributed to the renewed interest in these molecules as potential antimicrobials. Here, we give an overview on natural and semisynthetic aminoglycosides and their structural features and modes of action, focusing on the structural insight underlying resistance mechanisms. Developments on carbohydrate chemistry and microarray technology are highlighted as powerful approaches toward generation of new aminoglycosides and for screening their interactions with RNAs and proteins. The link between antibiotic uptake and the human gut microbiome is also addressed, focusing on gut microbiome function and composition, antibiotic-induced alterations in host health, and antibiotic resistance. In addition, strategies to modulate human microbiome responses to antibiotics are discussed as novel approaches for aminoglycoside usage and for the effectiveness of antibiotic therapy.
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Keywords: aminoglycosides; antibiotics; glycomics; gut microbiome; microarrays; modifying enzymes; resistance mechanisms

Statistical methodology for scale-up of an anti-solvent crystallization process in the pharmaceutical industry - Tulcidas, Ameessa; Susana Nascimento; Santos, Bruno; Carlos Alvarez; Sylwin Pawlowski; Rocha, Fernando (Separation and Purification Technology, 2019)
The scale-up of crystallization processes is a challenging step in production of active pharmaceutical ingredients (APIs). When moving from lab to industrial scale, the mixing conditions tend to modify due to the different geometry and agitation performance, which is particularly important in anti-solvent crystallizations where the size of the crystals depends on the mixing and incorporation of the anti-solvent in the solution. In this work, the results obtained in anti-solvent lab-scale crystallization experiments were used to develop multivariate statistical models predicting Particle Size Distribution (PSD) parameters (Dv10, Dv50 and Dv90) in function of predictors such as percentage of volume, power per volume and tip speed. Firstly, the collinearity among the predictors was assessed by Variance Inflation Factor (VIF) diagnosis. Subsequently, least squares method was employed to find correlations among the predictors and output variables. The optimization of the models was executed by testing quadratic, logarithmic and square root terms of the predictors and removing the least statistically significant regression coefficient. The quality of the fitting was evaluated in terms of adjusted R2 (R2adj). The modelled Dv10, Dv50 and Dv90 values presented a good fitting to the experimental data, with R2adj higher than 0.79, either when using power per volume or tip speed along the percentage of volume as predictors. Afterwards, the particle size distribution parameters of industrial scale production were predicted using the previously developed models. The deviations between predicted and experimental values were lower than 17%. This demonstrates that multivariate statistical models developed in lab-scale conditions can be successfully used to predict particle size distribution in industrial-size vessels.
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Keywords: Anti-solvent crystallization; Multiple linear regression; particle size distribution; Scale-up; Statistical modelling

Streptococcus dysgalactiae subsp. dysgalactiae isolated from milk of the bovine udder as emerging pathogens: In vitro and in vivo infection of human cells and zebrafish as biological models - Alves-Barroco, Cinthia; Catarina Roma-Rodrigues; Luís R. Raposo; Brás, Catarina; Mário Diniz; Caço, João; Costa, Pedro M.; Ilda Santos-Sanches; Alexandra R. Fernandes (MicrobiologyOpen, 2019)
Abstract Streptococcus dysgalactiae subsp. dysgalactiae (SDSD) is a major cause of bovine mastitis and has been regarded as an animal-restricted pathogen, although rare infections have been described in humans. Previous studies revealed the presence of virulence genes encoded by phages of the human pathogen Group A Streptococcus pyogenes (GAS) in SDSD isolated from the milk of bovine udder with mastitis. The isolates SDSD VSD5 and VSD13 could adhere and internalize human primary keratinocyte cells, suggesting a possible human infection potential of bovine isolates. In this work, the in vitro and in vivo potential of SDSD to internalize/adhere human cells of the respiratory track and zebrafish as biological models was evaluated. Our results showed that, in vitro, bovine SDSD strains could interact and internalize human respiratory cell lines and that this internalization was dependent on an active transport mechanism and that, in vivo, SDSD are able to cause invasive infections producing zebrafish morbidity and mortality. The infectious potential of these isolates showed to be isolate-specific and appeared to be independent of the presence or absence of GAS phage-encoded virulence genes. Although the infection ability of the bovine SDSD strains was not as strong as the human pathogenic S. pyogenes in the zebrafish model, results suggested that these SDSD isolates are able to interact with human cells and infect zebrafish, a vertebrate infectious model, emerging as pathogens with zoonotic capability.
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Keywords: Bovine; host adhesion/internalization; Streptococcus dysgalactiae subsp. dysgalactiae; systemic infection; Zebrafish

Structural and Functional Relevance of the Conserved Residue V13 in the Triheme Cytochrome PpcA from Geobacter sulfurreducens - Joana M Dantas; Portela, Pilar C.; Fernandes, Ana P.; Londer, Yuri Y.; Xiaojing Yang; Norma E.C. Duke; Schiffer, Marianne; P Raj Pokkuluri; Salgueiro, , Carlos A. (The Journal of Physical Chemistry B, 2019)
The triheme cytochrome PpcA from Geobacter sulfurreducens is highly abundant under several growth conditions and is important for extracellular electron transfer. PpcA plays a central role in transferring electrons resulting from the cytoplasmic oxidation of carbon compounds to the cell exterior. This cytochrome is designed to couple electron and proton transfer at physiological pH, a process achieved via the selection of dominant microstates during the redox cycle of the protein, which are ultimately regulated by a well-established order of oxidation of the heme groups. The three hemes are covered only by a polypeptide chain of 71 residues and are located in the small hydrophobic core of the protein. In this work, we used NMR and X-ray crystallography to investigate the structural and functional role of a conserved valine residue (V13) located within van der Waals contact of hemes III and IV. The residue was replaced by alanine (V13A), isoleucine (V13I), serine (V13S), and threonine (V13T) to probe the effects of the side chain volume and polarity. All mutants were found to be as equally thermally stable as the native protein. The V13A and V13T mutants produced crystals and their structures were determined. The side chain of the threonine residue introduced in V13T showed two conformations, but otherwise the two structures did not show significant changes from the native structure. Analysis of the redox behavior of the four mutants showed that for the hydrophobic replacements (V13A and V13I) the redox properties, and hence the order of oxidation of the hemes, were unaffected in spite of the larger side chain, isoleucine, showing two conformations with minor changes of the protein in the heme core. On the other hand, the polar replacements (V13S and V13T) showed the presence of two more distinctive conformations, and the oxidation order of the hemes was altered. Overall, it is striking that a single residue with proper size and polarity, V13, was naturally selected to ensure a unique conformation of the protein and the order of oxidation of the hemes, endowing the cytochrome PpcA with the optimal functional properties necessary to ensure effectiveness in the extracellular electron transfer respiratory pathways of G. sulfurreducens.
PMID: 30875222

Synaptic and neuromorphic functions: General discussion - Berg, A.I.; Brivio, S.; Brown, S.; Burr, G.; Deswal, S.; Deuermeier, J.; Gale, E.; Hwang, H.; Ielmini, D.; Indiveri, G.; Kenyon, A.J.; Kiazadeh, A.; et al. (Faraday Discussions, 2019)
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cited By 0

Systematic exploration of predicted destabilizing nonsynonymous single nucleotide polymorphisms (nsSNPs) of human aldehyde oxidase: A Bio-informatics study - Coelho, Catarina; Muthukumaran, Jayaraman; Santos-Silva, Teresa; Romão, Maria João (Pharmacology Research & Perspectives, 2019)
Abstract Aldehyde Oxidase (hAOX1) is a cytosolic enzyme involved in the metabolism of drugs and xenobiotic compounds. The enzyme belongs to the xanthine oxidase (XO) family of Mo containing enzyme and is a homo-dimer of two 150 kDa monomers. Nonsynonymous Single Nucleotide Polymorphisms (nsSNPs) of hAOX1 have been reported as affecting the ability of the enzyme to metabolize different substrates. Some of these nsSNPs have been biochemically and structurally characterized but the lack of a systematic and comprehensive study regarding all described and validated nsSNPs is urgent, due to the increasing importance of the enzyme in drug development, personalized medicine and therapy, as well as in pharmacogenetic studies. The objective of the present work was to collect all described nsSNPs of hAOX1 and utilize a series of bioinformatics tools to predict their effect on protein structure stability with putative implications on phenotypic functional consequences. Of 526 nsSNPs reported in NCBI-dbSNP, 119 are identified as deleterious whereas 92 are identified as nondeleterious variants. The stability analysis was performed for 119 deleterious variants and the results suggest that 104 nsSNPs may be responsible for destabilizing the protein structure, whereas five variants may increase the protein stability. Four nsSNPs do not have any impact on protein structure (neutral nsSNPs) of hAOX1. The prediction results of the remaining six nsSNPs are nonconclusive. The in silico results were compared with available experimental data. This methodology can also be used to identify and prioritize the stabilizing and destabilizing variants in other enzymes involved in drug metabolism.
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Keywords: Aldehyde Oxidase; computational genomic; in silico analysis; pharmacogenetic; single nucleotide polymorphism

Ultrafast Low-Temperature Crystallization of Solar Cell Graded Formamidinium-Cesium Mixed-Cation Lead Mixed-Halide Perovskites Using a Reproducible Microwave-Based Process - Brites, Maria João; Barreiros, Maria Alexandra; Corregidor, Victoria; Luis C. Alves; V. Pinto, Joana; Mendes, Manuel J.; Elvira Fortunato; Rodrigo Martins; Mascarenhas, João (ACS Applied Energy Materials, 2019)
The control of morphology and crystallinity of solution-processed perovskite thin-films for solar cells is the key for further enhancement of the devices’ power conversion efficiency and stability. Improving crystallinity and increasing grain size of perovskite films is a proven way to boost the devices’ performance and operational robustness, nevertheless this has only been achieved with high-temperature processes. Here, we present an unprecedented low-temperature (<80 °C) and ultrafast microwave (MW) annealing process to yield uniform, compact, and crystalline FA0.83Cs0.17Pb(I(1–x)Brx)3 perovskite films with full coverage and micrometer-scale grains. We demonstrate that the nominal composition FA0.83Cs0.17PbI1.8Br1.2 perovskite films annealed at 100 W MW power present the same band gap, similar morphology, and crystallinity of conventionally annealed films, with the advantage of being produced at a lower temperature (below 80 °C vs 185 °C) and during a very short period of time (∼2.5 min versus 60 min). These results open new avenues to fabricate band gap tunable perovskite films at low temperatures, which is of utmost importance for mechanically flexible perovskite cells and monolithic perovskite based tandem cells applications.
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Valence change ReRAMs (VCM) - Experiments and modelling: General discussion - Aono, M.; Baeumer, C.; Bartlett, P.; Brivio, S.; Burr, G.; Burriel, M.; Carlos, E.; Deswal, S.; Deuermeier, J.; Dittmann, R.; Du, H.; Gale, E.; et al. (Faraday Discussions, 2019)
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cited By 0

Valorization of olive pomace by a green integrated approach applying sustainable extraction and membrane-assisted concentration - M. Antónia Nunes; Sylwin Pawlowski; Anabela S.G. Costa; Rita C. Alves; M. Beatriz P.P. Oliveira; Velizarov, Svetlozar (Science of The Total Environment, 2019)
Olive pomace is a semi-solid paste resulting from the two-phase olive oil production, being the most significant waste generated by this agro-industry. Olive pomace is reported as an environmental hazard due to its high content in phenolic compounds (phytotoxic). Nevertheless, these compounds, when recovered, can have impactful actions in different human physiological conditions, namely, skin protection, dysfunction treatment or diseases prevention. Therefore, their recovery from olive pomace is crucial for environmental and economical sustainability, without forgetting the functional challenge. In a previous work, lipid and aqueous fractions of olive pomace were studied regarding its major bioactive compounds. The present research aims to describe an environmentally friendly integrated approach to extract and concentrate (by a pressure-driven membrane processing) the phytotoxic compounds of olive pomace. Three types of polymeric composite membranes (NF90, NF270 and BW30) were tested. The composition of the resulting streams (permeates and concentrates) were compared and the process efficiency assessed based on: (1) antioxidant activity and total phenolic and flavonoid contents; (2) inorganic elemental composition (by Inductively Coupled Plasma Atomic Emission Spectroscopy); (3) pH, conductivity and total organic carbon; and (4) permeate flux, membranes' apparent target solutes rejection and fouling index. The BW30 membrane presented the lowest fouling index and was the most effective for extracts concentration, with no phenolic compounds in the permeates, preventing completely the loss of such compounds.
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Keywords: Bioactive compounds; Nanofiltration; Olive pomace; Phytotoxicity; Reverse osmosis; sustainability

Sulfur dioxide induced aggregation of wine thaumatin-like proteins: Role of disulfide bonds - Chagas, Ricardo; Laia, Cesar A. T.; Ferreira, Ricardo B.; Ferreira, Luisa M. (FOOD CHEMISTRY, 2018)
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Gold nanoprobe-based non-crosslinking hybridization for molecular diagnostics: an update - Baptista, Pedro V (Expert Review Of Molecular Diagnostics, 2018)
Introduction: An update on the uses and applications of the non-cross-linking (NCL) hybridization assay based on the spectral modulation of gold nanoparticles (AuNPs) are presented, emphasizing DNA and RNA detection. Areas covered: Nanotechnology is strongly impacting the way we address diagnostics and therapeutics. In fact, nanoscale devices and particles have been used in a variety of platforms for improved biosensing and, more interestingly, for molecular diagnostics. AuNPs have been used in a great diversity of DNA and RNA detection strategies that are based on their nanoscale properties. Their unique optical properties have put them at the forefront of colorimetric sensing platforms. Among these, those relying on the NCL mechanism using DNA-modified AuNPs have shown remarkable versatility and simplicity for molecular detection of human pathogens, identification of single base alterations at the basis of human disease, gene expression, among others. Application of the NCL assay to molecular diagnostics will be discussed considering the challenges for validation and clinically relevant targets. Expert commentary: Integration of the NCL approach using AuNPs into chip biosensing platforms, projecting miniaturization and portability, will be addressed in terms of the future, i.e. clinical validation and translation to market.
Sem PDF conforme despacho. info:eu-repo/grantAgreement/FCT/5876/147258/PT# This work was supported by the Unidade de Ciências Biomoleculares Aplicadas - UCIBIO which is financed by national funds from FCT/MEC (UID/Multi/04378/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728).
Keywords: biodetection; DNA; Gold nanoparticles; Molecular diagnostics; Nanodiagnostics; Nanoprobes; non-cross-linking; RNA

{CHAPTER 2 Structural Elucidation of Macromolecules} - Ana Luísa Carvalho; Santos-Silva, Teresa; Romão, Maria João; Eurico, J; Marcelo, Filipa (Essential Techniques for Medical and Life Scientists: A Guide to Contemporary Methods and Current Applications with the Protocols, 2018)
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Keywords: cryo-em; Drug Design; ligand interactions; macromolecular structure; NMR; protein-; saxs; X-ray crystallography

The Important Role of the Nuclearity, Rigidity, and Solubility of Phosphane Ligands in the Biological Activity of Gold(I) Complexes - Svahn, Noora; Moro, Artur J.; Catarina Roma-Rodrigues; Puttreddy, Rakesh; Kari Rissanen; Baptista, Pedro V; Fernandes, Alexandra R; Lima, João Carlos; Laura Rodríguez (Chemistry - A European Journal, 2018)
A series of 4-ethynylaniline gold(I) complexes containing monophosphane (1,3,5-triaza-7-phosphaadamantane (pta; 2), 3,7-diacetyl-1,3,7-triaza-5-phosphabicyclo[3.3.1]nonane (3), and PR3 , with R=naphthyl (4), phenyl (5), and ethyl (6)) and diphosphane (bis(diphenylphosphino)acetylene (dppa; 7), trans-1,2-bis(diphenylphosphino)ethene (dppet; 8), 1,2-bis(diphenylphosphino)ethane (dppe; 9), and 1,3-bis(diphenylphosphino)propane (dppp; 10)) ligands have been synthesized and their efficiency against tumor cells evaluated. The cytotoxicity of complexes 2-10 was evaluated in human colorectal (HCT116) and ovarian (A2780) carcinoma as well as in normal human fibroblasts. All the complexes showed a higher antiproliferative effect in A2780 cells, with the cytotoxicity decreasing in the following order 5>6=9=10>8>2>4>7>3. Complex 4 stands out for its very high selectivity towards ovarian carcinoma cells (IC50 =2.3 μm) compared with colorectal carcinoma and normal human fibroblasts (IC50 >100 μm), which makes this complex very attractive for ovarian cancer therapy. Its cytotoxicity in these cells correlates with the induction of the apoptotic process and an increase of intracellular reactive oxygen species (ROS). The effects of the nuclearity, rigidity, and solubility of these complexes on their biological activity were also analyzed. X-ray crystal structure determination allowed the identification of short N-H⋅⋅⋅π contacts as the main driving forces for the three-dimensional packing in these molecules.
Sem PDF conforme despacho. info:eu-repo/grantAgreement/FCT/5876/147218/PT# info:eu-repo/grantAgreement/FCT/5876/147258/PT# The authors are grateful to the Ministry of Economy, Industry and Competitiveness of Spain (AEI/FEDER, UE Project CTQ2016-76120-P). This work was also supported by the Associated Laboratory for Sustainable Chemistry, Clean Processes and Technologies, LAQV, which is financed by national funds from FCT/MEC (UID/QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265) and by the Unidade de Cithornncias Biomoleculares Aplicadas-UCIBIO, which is financed by national funds from FCT/MEC (UID/Multi/04378/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728). COST Action CM1402 is also acknowledged. N.S. is also indebted to the Erasmus exchange mobility program. We also would like to thank Ms. Andrea Pinto and Mr. Oussama Kheireedine Nehar for the help in some of the syntheses performed. The University of Jyvaskyla (K.R.) and The Academy of Finland (R.P., grant no. 298817) are kindly acknowledged for financial support.
Keywords: antitumor agents; Apoptosis; biological activity; Gold; X-ray diffraction

POxylated Dendrimer-Based Nano-in-Micro Dry Powder Formulations for Inhalation Chemotherapy - Restani, Rita B.; Pires, Rita F.; Anna Tolmatcheva; Rita Cabral; Baptista, Pedro V; Fernandes, Alexandra R; Casimiro, Teresa; Bonifácio, Vasco D. B.; Aguiar-Ricardo, Ana (ChemistryOpen, 2018)
POxylated polyurea dendrimer (PUREG4OOx48)-based nanoparticles were loaded with paclitaxel (PTX) and doxorubicin (DOX) and micronized with chitosan (CHT) by using supercritical CO2-assisted spray drying (SASD). Respirable, biocompatible, and biodegradable dry powder formulations (DPFs) were produced to effectively transport and deliver the chemotherapeutics with a controlled rate to the deep lung. In vitro studies performed with the use of the lung adenocarcinoma cell line showed that DOX@PUREG4OOx48 nanoparticles were much more cytotoxic than the free drug. Additionally, the DPFs did not show higher cytotoxicity than the respective nanoparticles, and DOX-DPFs showed a higher chemotherapeutic effect than PTX formulations in adenocarcinoma cells.
Sem PDF conforme despacho. info:eu-repo/grantAgreement/FCT/5876/147218/PT# info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBD%2F66858%2F2009/PT# This work was supported by the Associate Laboratory for Green Chemistry-LAQV, which is financed by national funds from FCT/MCTES (UID/QUI/50006/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER -007265), the Unidade de Cithornncias Biomoleculares Aplicadas UCIBIO-REQUIMTE, which is financed by national funds from FCT/MEC (UID/Multi/04378/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728). The authors acknowledge the Ph.D. grants SFRH/BD/66858/2009 (R.B.R.) and SFRH/BD/109006/2015 (R.F.P.). T.C. also acknowledges FCT-Lisbon for the IF/00915/2014 contract.
Keywords: chemotherapy; composite particles; Dendrimers; Drug delivery; Pulmonary delivery

A double Philadelphia chromosome-positive chronic myeloid leukemia patient, co-expressing P210BCR-ABL1 and P195BCR-ABL1 isoforms - Raquel Vinhas; Lourenço, Alexandra; Susana Santos; Patrícia Ribeiro; Silva, Madalena; {de Sousa}, Aida Botelho; Baptista, Pedro V; Fernandes, Alexandra R (Haematologica, 2018)
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info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/PD/PD%2FBD%2F52211%2F2013/PT# co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728).
Keywords: CML PATIENT; E6A2 BCR-ABL; FUSION TRANSCRIPT; IMATINIB; therapy

Cellulose-Based Biomimetics and Their Applications - Ana P.C. Almeida; Canejo, João P; Fernandes, Susete N.; Coro Echeverria; Almeida, Pedro L; Godinho, Maria H (Advanced Materials, 2018)
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Evaluation of cell toxicity and DNA and protein binding of green synthesized silver nanoparticles - Ribeiro, A P C; Anbu, S.; Alegria, E C B A; Fernandes, A. R.; Baptista, P. V.; Mendes, R.; Matias, A S; Mendes, M.; Guedes da Silva, M F C; Pombeiro, A J L (Biomedicine and Pharmacotherapy, 2018)
Silver nanoparticles (AgNPs) were prepared by GREEN chemistry relying on the reduction of AgNO3 by phytochemicals present in black tea extract. AgNPs were fully characterized by transmission electron microscopy (TEM), ultraviolet-visible spectroscopy ((UV-vis)), X-ray diffraction (XRD) and energy dispersive absorption spectroscopy (EDS). The synthesized AgNPs induced a decrease of the cell viability in a dose-dependent manner with a low IC50 (0.5 ± 0.1 μM) for an ovarian carcinoma cell line (A2780) compared to primary human fibroblasts (IC50 5.0 ± 0.1 μM). The DNA binding capability of CT (calf thymus) DNA was investigated using electronic absorption and fluorescence spectroscopies, circular dichroism and viscosity titration methods. Additionally, the AgNPs strongly quench the intrinsic fluorescence of BSA, as determined by synchronous fluorescence spectra.
info:eu-repo/grantAgreement/FCT/5876/147216/PT# info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBPD%2F90883%2F2012/PT# info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBPD%2F76451%2F2011/PT# sem pdf conforme despacho. co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728). SFRH/BD/132163/2017 to R. Mendes.
Keywords: BSA interaction; Cancer cell line; cytotoxicity; DNA interaction; Green chemistry; Silver nanoparticles (AgNPs)

Optical and Structural Characterization of a Chronic Myeloid Leukemia DNA Biosensor - Mílton Cordeiro; Otrelo-Cardoso, Ana Rita Castro; Svergun, Dmitri I.; Konarev, Petr V.; Lima, João Carlos; Santos-Silva, Teresa; Baptista, Pedro Viana (ACS Chemical Biology, 2018)
Selective base pairing is the foundation of DNA recognition. Here, we elucidate the molecular and structural details of a FRET-based two-component molecular beacon relying on steady-state fluorescence spectroscopy, small-angle X-ray scattering (SAXS), microscale thermophoresis (MST), and differential electrophoretic mobility. This molecular beacon was designed to detect the most common fusion sequences causing chronic myeloid leukemia, e14a2 and e13a2. The emission spectra indicate that the self-assembly of the different components of the biosensor occurs sequentially, triggered by the fully complementary target. We further assessed the structural alterations leading to the specific fluorescence FRET signature by SAXS, MST, and the differential electrophoretic mobility, where the size range observed is consistent with hybridization and formation of a 1:1:1 complex for the probe in the presence of the complementary target and revelator. These results highlight the importance of different techniques to explore conformational DNA changes in solution and its potential to design and characterize molecular biosensors for genetic disease diagnosis.
Sem PDF conforme despacho. info:eu-repo/grantAgreement/FCT/5876/147258/PT# info:eu-repo/grantAgreement/FCT/SFRH/SFRH%2FBD%2F85806%2F2012/PT# This work was supported by the Unidade de Cienciaŝ Biomoleculares Aplicadas-UCIBIO, which is financed by national funds from FCT/MEC (UID/Multi/04378/2013) and cofinanced by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728) and PTDC/ QEQ-MED/1902/2014. A.R.O.-C. and M.C. thank FCT/ MEC for SFRH/BD/85806/2012 and SFRH/BD/87836/ 2012, respectively. The authors thank the EMBL P12 (DESY, Hamburg, Germany) and BM29 (ESRF, Grenoble, France) beamline staff for assistance during data collection. P.V.K. acknowledges the support from Federal Agency of Scientific Organizations (Agreement No 007-Γ3/43363/26).; 6th Annual Conference of the International Chemical Biology Society (ICBS), ICBS ; Conference date: 17-10-2017 Through 20-10-2017
Keywords: Small-angle scattering; X-Rays

A Different Approach to the EGFR Inhibitor Gefitinib Involving Solid-Phase Synthesis - Sequeira, Andre; Lourenco, Ana; Ferreira, Luisa Maria; Branco, Paula Serio; Mendes, Zita; Lourenco, Nuno M. T.; Figueiredo, Margarida; Carvalho, Luisa C. R. (SYNLETT, 2018)
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(R)-Metacycloprodigiosin-HCl: Chiroptical properties and structure - Peixoto, Daniela; Ferreira, Elisabete P.; Lourenco, Ana M.; Johnson, Jordan L.; Lobo, Ana M; Polavarapu, Prasad L. (CHIRALITY, 2018)
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Investigation of single phase Cu2ZnSn(x)Sb(1−x)S4 compounds processed by mechanochemical synthesis - Neves, F.; Stark, A.; Schell, N.; M. J. Mendes; Aguas, H.; E. Fortunato; R. Martins; J. B. Correia; Joyce, A. (Phys. Rev. Materials, 2018)
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Nano-strategies to fight multidrug resistant bacteria-{"}A Battle of the Titans{"} - Baptista, Pedro V; McCusker, Matthew P.; Carvalho, Andreia; Ferreira, Daniela A.; Mohan, Niamh M.; Martins, M; Fernandes, Alexandra R (Frontiers in Microbiology, 2018)
Infectious diseases remain one of the leading causes of morbidity and mortality worldwide. The WHO and CDC have expressed serious concern regarding the continued increase in the development of multidrug resistance among bacteria. Therefore, the antibiotic resistance crisis is one of the most pressing issues in global public health. Associated with the rise in antibiotic resistance is the lack of new antimicrobials. This has triggered initiatives worldwide to develop novel and more effective antimicrobial compounds as well as to develop novel delivery and targeting strategies. Bacteria have developed many ways by which they become resistant to antimicrobials. Among those are enzyme inactivation, decreased cell permeability, target protection, target overproduction, altered target site/enzyme, increased efflux due to over-expression of efflux pumps, among others. Other more complex phenotypes, such as biofilm formation and quorum sensing do not appear as a result of the exposure of bacteria to antibiotics although, it is known that biofilm formation can be induced by antibiotics. These phenotypes are related to tolerance to antibiotics in bacteria. Different strategies, such as the use of nanostructured materials, are being developed to overcome these and other types of resistance. Nanostructured materials can be used to convey antimicrobials, to assist in the delivery of novel drugs or ultimately, possess antimicrobial activity by themselves. Additionally, nanoparticles (e.g., metallic, organic, carbon nanotubes, etc.) may circumvent drug resistance mechanisms in bacteria and, associated with their antimicrobial potential, inhibit biofilm formation or other important processes. Other strategies, including the combined use of plant-based antimicrobials and nanoparticles to overcome toxicity issues, are also being investigated. Coupling nanoparticles and natural-based antimicrobials (or other repurposed compounds) to inhibit the activity of bacterial efflux pumps; formation of biofilms; interference of quorum sensing; and possibly plasmid curing, are just some of the strategies to combat multidrug resistant bacteria. However, the use of nanoparticles still presents a challenge to therapy and much more research is needed in order to overcome this. In this review, we will summarize the current research on nanoparticles and other nanomaterials and how these are or can be applied in the future to fight multidrug resistant bacteria.
Sem PDF conforme despacho. info:eu-repo/grantAgreement/FCT/5876/147258/PT# This work was supported by the Unidade de Ciencias Biomoleculares Aplicadas-UCIBIO, which is financed by National Funds from FCT/MEC (PTDC_CVT-EPI_6685_2014; UID/Multi/04378/2013) and co-financed by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007728). DF is funded by the Trinity College Dublin Postgraduate Research (1252) Studentship. NM is funded by the Irish Research Council under the employment-based programme EBPPG/2015/233 in conjunction with Nuritas limited. We would like to acknowledge Ana Sofia Santos for preliminary revision of the manuscript.
Keywords: antimicrobial resistance; Multidrug resistance; Nanomaterials; nanoparticles; nanotheranostics; Novel antimicrobial agents; Plant-based compounds

Synthesis, Cytotoxicity Evaluation in Human Cell Lines and in Vitro DNA Interaction of a Hetero-Arylidene-9(10H)-Anthrone - Peixoto, Daniela; Figueiredo, Margarida; Malta, Gabriela; Catarina Roma-Rodrigues; Pedro V. Baptista; Alexandra R. Fernandes; Barroso, Sonia; Carvalho, Ana Luisa; Afonso, Carlos A. M.; Ferreira, Luisa M.; Branco, Paula S. (EUROPEAN JOURNAL OF ORGANIC CHEMISTRY, 2018)
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Nanoparticles as Delivery Systems in Cancer Therapy: Focus on Gold Nanoparticles and Drugs - Carvalho, Andreia; Fernandes, Alexandra R; Baptista, Pedro V (Applications of Targeted Nano Drugs and Delivery Systems, 2018)
Conventional cancer chemotherapy presents several bottlenecks, such as lack of specificity that impacts healthy tissues, rapid drug metabolism, and both intrinsic/acquired drug resistances varying in patient status, which altogether lead to reduction of efficacy. To overcome these issues and improve efficacy, combination with novel nanotechnology approaches-cancer nanomedicine-in the areas of imaging, diagnosis, and drug delivery are being proposed. These developments have been focused upon the preparation and application of nanoparticles for cancer therapy. Gold nanoparticle (AuNP) applications have been projected for improved imaging, diagnosis, and therapy, due to their exquisite physicochemical and optical properties showing potential applications as drug/gene carriers, photothermal and contrast agents. All these features may potentiate selective drug delivery, thus improving efficacy and reducing side effects. In this chapter, we shall discuss applications of nanoparticles with focus on AuNPs as efficient targeted (drug) delivery systems in cancer therapy.
Publisher Copyright: © 2019 Elsevier Inc. All rights reserved.
Keywords: Cancer; Delivery systems; Drug Delivery Systems; Gold nanoparticles; Nano drug; nanomedicines; Targeted nano drugs