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2019
Bravo, C, Robalo PM, Marques F, Fernandes AR, Sequeira DA, M. Piedade FM, Garcia HM, de Brito MVJ, Morais TS.  2019.  First heterobimetallic Cu(i)–dppf complexes designed for anticancer applications: synthesis, structural characterization and cytotoxicity, 2019. New Journal of Chemistry. 43(31):12308-12317. AbstractWebsite

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.

Oliveira, H, Roma-Rodrigues C, Santos A, Veigas B, Bras N, Faria A, Calhau C, de Freitas V, Baptista PV, Mateus N, Fernandes AR, Fernandes I.  2019.  GLUT1 and GLUT3 involvement in anthocyanin gastric transport- Nanobased targeted approach, 2019. Sci Rep. 9(1):789. AbstractWebsite

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.

Santos, MM, Raposo LR, Carrera GVSM, Costa A, Dionisio M, Baptista PV, Fernandes AR, Branco LC.  2019.  Ionic Liquids and Salts from Ibuprofen as Promising Innovative Formulations of an Old Drug, 2019. ChemMedChem. 14(9):907-911. AbstractWebsite

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.

Sutradhar, M, Fernandes AR, Paradinha F, Rijo P, Garcia C, Roma-Rodrigues C, Pombeiro AJL, Charmier AJ.  2019.  A new Cu(II)-O-Carvacrotinate complex: Synthesis, characterization and biological activity, 2019. J Inorg Biochem. 190:31-37. AbstractWebsite

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.

Kourmentza, C, Araujo D, Sevrin C, Roma-Rodriques C, Lia Ferreira J, Freitas F, Dionisio M, Baptista PV, Fernandes AR, Grandfils C, Reis MAM.  2019.  Occurrence of non-toxic bioemulsifiers during polyhydroxyalkanoate production by Pseudomonas strains valorizing crude glycerol by-product, 2019. Bioresour Technol. 281:31-40. AbstractWebsite

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.

Almeida, APC, Querciagrossa L, Silva PES, Gonçalves F, Canejo JP, Almeida PL, Godinho MH, Zannoni C.  2019.  Reversible water driven chirality inversion in cellulose-based helices isolated from Erodium awns, 2019. Soft Matter. 15(13):2838-2847.: The Royal Society of Chemistry AbstractWebsite

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.

Alves-Barroco, C, Roma-Rodrigues C, Raposo LR, Bras C, Diniz M, Caco J, Costa PM, Santos-Sanches I, Fernandes AR.  2019.  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, 2019. Microbiologyopen. 8(1):e00623. AbstractWebsite

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.

Fortes, P, Simoes S, Gouveia JP, Seixas J.  2019.   Electricity, the silver bullet for the deep decarbonisation of the energy system? Cost-effectiveness analysis for Portugal. Applied Energy. 237:292-303.
Marques, AC, Miglietta D, Gaspar G, Baptista AC, Gaspar A, Perdigão A, Soares I, Bianchi C, Sousa D, Morais Faustino BM, Amaral VS, Santos T, Gonçalves AP, da Silva RC, Giorgis F, Ferreira I.  2019.   Synthesis of thermoelectric magnesium-silicide pastes for 3D printing, electrospinning and low-pressure spray. Materials for Renewable and Sustainable Energy. :8-21.
Mota, C, Santos Silva T, Terao M, Garattini E, Romão MJ, Leimkuehler S.  2019.  Aldehyde Oxidases as Enzymes in Phase I Drug Metabolism. Pharmaceutical Biocatalysis. (Peter Grunwald, Ed.)., New York: Jenny Stanford Publishing
A.Rocha, Sousa D, Ferreira I, Diniz MS.  2019.  Biochemical responses in Danio rerio following exposure to CdS and ZnS Quantum Dots. Annals of Medicine. 51:71-71.
Santos, Â, Otero V, Vilarigues M.  2019.  Characterisation of glass and painting materials from 18th century hand-painted glass slides used for projection with Magic Lanterns. Interim Meeting of the ICOM-CC Glass and Ceramics Working Group − "Recent Advances in Glass and Ceramics Conservation 2019". :219-224., London, England, 5-7 September 2019 AbstractSantos et al (2019) ICOM-CC_GlassCeramics.pdf

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.

Szymczak, P, Rau MH, Monteiro JM, Pinho MG, Filipe SR, Vogensen FK, Zeidan AA, Janzen T.  2019.  A comparative genomics approach for identifying host-range determinants in Streptococcus thermophilus bacteriophages. Scientific Reports. 9(1):7991.
Machado, MA, Antin K-N, Rosado LS, Vilaça P, Santos TG.  2019.  Contactless high-speed eddy current inspection of unidirectional carbon fiber reinforced polymer. Composites Part B: Engineering. 168:226-235. AbstractWebsite

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.

Zanatta, M, Simon NM, dos Santos FP, Corvo MC, Cabrita EJ, Dupont J.  2019.  Correspondence on “Preorganization and Cooperation for Highly Efficient and Reversible Capture of Low-Concentration CO2 by Ionic Liquids”. Angewandte Chemie International Edition. AbstractWebsite

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.

Cristovão, AF, Sousa D, Silvestre F, Ropio I, Gaspar A, Henriques C, Velhinho A, Baptista AC, Faustino M, Ferreira I.  2019.  Customized tracheal design using 3D printing of a polymer hydrogel: influence of UV laser cross-linking on mechanical properties. 3D Printing in Medicine. 5:12. AbstractWebsite

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.

Cristovão, AF, Sousa D, Silvestre F, Ropio I, Gaspar A, Henriques C, Velhinho A, Baptista AC, Faustino M, Ferreira I.  2019.  Customized tracheal design using 3D printing of a polymer hydrogel: influence of UV laser cross-linking on mechanical properties. 3D Print Med. 5:12.
Collaço, F, Simoes SG, Dias L, Duic N, Seixas J, Bermann C.  2019.  The dawn of urban energy planning – synergies between energy and urban planning for São Paulo (Brazil) megacity. Journal of Cleaner Production. 215:458-479,doi:https://doi.org/10.1016/j.jclepro.2019.01.013.
dos Santos, R, Figueiredo C, Viecinski AC, Pina AS, Barbosa AJM, Roque ACA.  2019.  Designed affinity ligands to capture human serum albumin. Journal of Chromatography A. 1583:88-97. AbstractWebsite

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.

Fernandes, TM, Morgado L, Salgueiro CA, Turner DL.  2019.  Determination of the magnetic properties and orientation of the heme axial ligands of PpcA from G. metallireducens by paramagnetic NMR. Journal of Inorganic Biochemistry. 198:110718. AbstractWebsite

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.

Esteves C, Santos GMC, Alves C, Palma S, Porteira AR, Filho J, HA C, Alves VD, Faustino BMM, Ferreira I, Gamboa H, Roque ACA.  2019.  Effect of film thickness in gelatin hybrid gels for artificial olfaction. Materials Today Bio. 1:-. AbstractPDFWebsite

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.

Esteves, C, Santos GMC, Alves C, Palma SICJ, Porteira AR, Costa HMA, Alves VD, Faustino BMM, Ferreira I, Gamboa H.  2019.  Effect of film thickness in gelatine hybrid gels for artificial olfaction. Materials Today Bio. 1:100002.
Vieira, T, Silva JC, do Rego BAM, Borges JB, Henriques C.  2019.  Electrospun biodegradable chitosan based-poly(urethane urea) scaffolds for soft tissue engineering. Materials Science and Engineering: C. 103:109819. AbstractWebsite

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.

Kyprianou, I, Serghides D, Varo A, Gouveia JP, Kopeva D, Murauskaite L.  2019.  Energy Poverty Policies and Measures in 5 EU Countries: A Comparative Study.. Energy and Buildings. 196:46-60.