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2022
Ramos, A, Isufi B, Marreiros R, Bolesova M, Gajdsova K.  2022.  Rational Use of FPFRC in Slab-Connections Under Reversed Horizontal Cyclic Loading. Engineering Structures. Accepted for publication Abstract

Slab – column connections that are subjected to combined gravity and horizontal loading during an earthquake are prone to premature failure due to punching shear. Traditional solutions to avoid punching failure and to increase the displacement capacity of this type of connection include using stirrups and double-headed studs as shear reinforcement. The use of High-Performance Fiber Reinforced Concrete (HPFRC) in a small region of the slab around the column as a substitute for traditional solutions is investigated in this paper, because this material has the potential to reduce labor and material costs. To fulfill this objective, four slab specimens with a thickness of 150 mm were tested under combined gravity and reversed horizontal drifts. The results are discussed in detail. The experimental variables considered were the top flexural reinforcement ratio, the size of the HPFRC zone and the intensity of the gravity load. Previously published tests that serve as reference specimens are used to compare the results. The behavior of the specimens with HPFRC was substantially improved compared to the reference specimens in terms of drift capacity: from only 1.0% drift to above 5.5%, even though a very small quantity of HPFRC was used, extended up to only 1.5 times the effective depth of the slab from the face of the column. Specimens with HPFRC also behaved better when compared to specimens with High-Strength Concrete (HSC). Side effects of using HPFRC in the slab in the vicinity of the column include an increase of the unbalanced moment transfer capacity and lateral stiffness, as well as a reduction of the deflections of the slab.

Isufi, B, Almeida A, Marreiros R, Ramos A, Lúcio V.  2022.  Slab – column connection punching and ductility improvement methods for seismic response of buildings with flat slabs. Structural Concrete. 23:1385–1398.Website
Relvas, JP.  2022.  Utilização Racional de Betões de Alta Resistência Reforçados com Fibras de Aço em Lajes Fungiformes. NOVA School of Science and Technology. (António Pinho Ramos, Brisid Isufi, Eds.)., Caparica
Gonçalves, AM, Sousa Â, Pedro AQ, Romão MJ, Queiroz JA, Gallardo E, Passarinha LA.  2022.  Advances in Membrane-Bound Catechol-O-Methyltransferase Stability Achieved Using a New Ionic Liquid-Based Storage Formulation. International Journal of Molecular Sciences. 23, Number 13 AbstractWebsite

Membrane-bound catechol-O-methyltransferase (MBCOMT), present in the brain and involved in the main pathway of the catechol neurotransmitter deactivation, is linked to several types of human dementia, which are relevant pharmacological targets for new potent and nontoxic inhibitors that have been developed, particularly for Parkinson’s disease treatment. However, the inexistence of an MBCOMT 3D-structure presents a blockage in new drugs’ design and clinical studies due to its instability. The enzyme has a clear tendency to lose its biological activity in a short period of time. To avoid the enzyme sequestering into a non-native state during the downstream processing, a multi-component buffer plays a major role, with the addition of additives such as cysteine, glycerol, and trehalose showing promising results towards minimizing hMBCOMT damage and enhancing its stability. In addition, ionic liquids, due to their virtually unlimited choices for cation/anion paring, are potential protein stabilizers for the process and storage buffers. Screening experiments were designed to evaluate the effect of distinct cation/anion ILs interaction in hMBCOMT enzymatic activity. The ionic liquids: choline glutamate [Ch][Glu], choline dihydrogen phosphate ([Ch][DHP]), choline chloride ([Ch]Cl), 1- dodecyl-3-methylimidazolium chloride ([C12mim]Cl), and 1-butyl-3-methylimidazolium chloride ([C4mim]Cl) were supplemented to hMBCOMT lysates in a concentration from 5 to 500 mM. A major potential stabilizing effect was obtained using [Ch][DHP] (10 and 50 mM). From the DoE 146% of hMBCOMT activity recovery was obtained with [Ch][DHP] optimal conditions (7.5 mM) at −80 °C during 32.4 h. These results are of crucial importance for further drug development once the enzyme can be stabilized for longer periods of time.

Pinto, F, Lourenço AF, Pedrosa JFS, Gonçalves L, Ventura C, Vital N, Bettencourt A, Fernandes SN, da Rosa RR, Godinho MH, Louro H, Ferreira PJT, Silva MJ.  2022.  Analysis of the In Vitro Toxicity of Nanocelluloses in Human Lung Cells as Compared to Multi-Walled Carbon Nanotubes. Nanomaterials. 12, Number 9 AbstractWebsite

Cellulose micro/nanomaterials (CMNM), comprising cellulose microfibrils (CMF), nanofibrils (CNF), and nanocrystals (CNC), are being recognized as promising bio-nanomaterials due to their natural and renewable source, attractive properties, and potential for applications with industrial and economical value. Thus, it is crucial to investigate their potential toxicity before starting their production at a larger scale. The present study aimed at evaluating the cell internalization and in vitro cytotoxicity and genotoxicity of CMNM as compared to two multi-walled carbon nanotubes (MWCNT), NM-401 and NM-402, in A549 cells. The exposure to all studied NM, with the exception of CNC, resulted in evident cellular uptake, as analyzed by transmission electron microscopy. However, none of the CMNM induced cytotoxic effects, in contrast to the cytotoxicity observed for the MWCNT. Furthermore, no genotoxicity was observed for CNF, CNC, and NM-402 (cytokinesis-block micronucleus assay), while CMF and NM-401 were able to significantly raise micronucleus frequency. Only NM-402 was able to induce ROS formation, although it did not induce micronuclei. Thus, it is unlikely that the observed CMF and NM-401 genotoxicity is mediated by oxidative DNA damage. More studies targeting other genotoxicity endpoints and cellular and molecular events are underway to allow for a more comprehensive safety assessment of these nanocelluloses.

Ventura, C, Marques C, Cadete J, Vilar M, Pedrosa JFS, Pinto F, Fernandes SN, da Rosa RR, Godinho MH, Ferreira PJT, Louro H, Silva MJ.  2022.  Genotoxicity of Three Micro/Nanocelluloses with Different Physicochemical Characteristics in MG-63 and V79 Cells. Journal of Xenobiotics. 12:91–108., Number 2 AbstractWebsite

(1) Background: Nanocellulose is an innovative engineered nanomaterial with an enormous potential for use in a wide array of industrial and biomedical applications and with fast growing economic value. The expanding production of nanocellulose is leading to an increased human exposure, raising concerns about their potential health effects. This study was aimed at assessing the potential toxic and genotoxic effects of different nanocelluloses in two mammalian cell lines; (2) Methods: Two micro/nanocelluloses, produced with a TEMPO oxidation pre-treatment (CNFs) and an enzymatic pre-treatment (CMFs), and cellulose nanocrystals (CNCs) were tested in osteoblastic-like human cells (MG-63) and Chinese hamster lung fibroblasts (V79) using the MTT and clonogenic assays to analyse cytotoxicity, and the micronucleus assay to test genotoxicity; (3) Results: cytotoxicity was observed by the clonogenic assay in V79 cells, particularly for CNCs, but not by the MTT assay; CNF induced micronuclei in both cell lines and nucleoplasmic bridges in MG-63 cells; CMF and CNC induced micronuclei and nucleoplasmic bridges in MG-63 cells, but not in V79 cells; (4) Conclusions: All nanocelluloses revealed cytotoxicity and genotoxicity, although at different concentrations, that may be related to their physicochemical differences and availability for cell uptake, and to differences in the DNA damage response of the cell model.

Martins, {ICB }, Forte A, Diogo {HP }, Raposo {LR }, Baptista {PV}, Fernandes {AR}, Branco {LC }, Duarte T}{M.  2022.  A solvent‐free strategy to prepare amorphous salts of folic acid with enhanced solubility and cell permeability. Chemistry–Methods. 2, Number 6 Abstract

Eight new amorphous organic salts of folic acid (FA) were prepared by mechanochemistry. FA can prevent cardiovascular and neurological diseases. Mechanochemistry overcomes serious FA solubility issues avoiding the use of toxic solvents. Due to low FA solubility, therapeutic effects in supplements and drugs are not achieved. Current strategies to improve FA solubility include its derivatization by using complex synthetic procedures. Herein, a simple and green procedure, avoiding structural modifications, was designed using mechanochemistry. Biocompatible amine-derivative coformers were strategically combined with FA to obtain salts with good physicochemical properties. New 1 : 1 and 1 : 2 amorphous FA salts offer 10 to 10,000 times better aqueous solubility and 10 to 100 times better octanol-water partition coefficient values (Koctanol/water) than FA alone. Koctanol/water is considered as a surrogate of cell permeability. No toxic effects in normal human primary dermal fibroblasts were detected for the prepared FA salts. Our findings suggest that 1 : 2 FA salts of choline hydroxide and derivatives could be good candidates for future pharmaceutical/nutraceutical applications.

Moreira, IP, Esteves C, Palma SICJ, Ramou E, Carvalho ALM, Roque ACA.  2022.  Synergy between silk fibroin and ionic liquids for active gas-sensing materials. Materials Today Bio. :100290. AbstractWebsite

Silk fibroin is a biobased material with excellent biocompatibility and mechanical properties, but its use in bioelectronics is hampered by the difficult dissolution and low intrinsic conductivity. Some ionic liquids are known to dissolve fibroin but removed after fibroin processing. However, ionic liquids and fibroin can cooperatively give rise to functional materials, and there are untapped opportunities in this combination. The dissolution of fibroin, followed by gelation, in designer ionic liquids from the imidazolium chloride family with varied alkyl chain lengths (2–10 carbons) is shown here. The alkyl chain length of the anion has a large impact on fibroin secondary structure which adopts unconventional arrangements, yielding robust gels with distinct hierarchical organization. Furthermore, and due to their remarkable air-stability and ionic conductivity, fibroin ionogels are exploited as active electrical gas sensors in an electronic nose revealing the unravelled possibilities of fibroin in soft and flexible electronics.

Esteves, C, Palma SICJ, Costa HMA, Alves C, Santos GMC, Ramou E, Carvalho AL, Alves V, Roque ACA.  2022.  Tackling Humidity with Designer Ionic Liquid-Based Gas Sensing Soft Materials. Advanced Materials. 34:2107205., Number 8 AbstractWebsite

Abstract Relative humidity is simultaneously a sensing target and a contaminant in gas and volatile organic compound (VOC) sensing systems, where strategies to control humidity interference are required. An unmet challenge is the creation of gas-sensitive materials where the response to humidity is controlled by the material itself. Here, humidity effects are controlled through the design of gelatin formulations in ionic liquids without and with liquid crystals as electrical and optical sensors, respectively. In this design, the anions [DCA]− and [Cl]− of room temperature ionic liquids from the 1-butyl-3-methylimidazolium family tailor the response to humidity and, subsequently, sensing of VOCs in dry and humid conditions. Due to the combined effect of the materials formulations and sensing mechanisms, changing the anion from [DCA]− to the much more hygroscopic [Cl]−, leads to stronger electrical responses and much weaker optical responses to humidity. Thus, either humidity sensors or humidity-tolerant VOC sensors that do not require sample preconditioning or signal processing to correct humidity impact are obtained. With the wide spread of 3D- and 4D-printing and intelligent devices, the monitoring and tuning of humidity in sustainable biobased materials offers excellent opportunities in e-nose sensing arrays and wearable devices compatible with operation at room conditions.

2021
Cordeiro, R, Beira MJ, Cruz C, Figueirinhas JL, Corvo MC, Almeida PL, Rosatella AA, Afonso CAM, Daniel CI, Sebastiao PJ.  2021.  Tuning the H-1 NMR Paramagnetic Relaxation Enhancement and Local Order of {[}Aliquat](+)-Based Systems Mixed with DMSO, {JAN}. International Journal of Molecular Sciences. 22:706., Number {2} AbstractWebsite

{Understanding the behavior of a chemical compound at a molecular level is fundamental, not only to explain its macroscopic properties, but also to enable the control and optimization of these properties. The present work aims to characterize a set of systems based on the ionic liquids {[}Aliquat]{[}Cl] and {[}Aliquat]{[}FeCl4] and on mixtures of these with different concentrations of DMSO by means of H-1 NMR relaxometry, diffusometry and X-ray diffractometry. Without DMSO, the compounds reveal locally ordered domains, which are large enough to induce order fluctuation as a significant relaxation pathway, and present paramagnetic relaxation enhancement for the {[}Aliquat]{[}Cl] and {[}Aliquat]{[}FeCl4] mixture. The addition of DMSO provides a way of tuning both the local order of these systems and the relaxation enhancement produced by the tetrachloroferrate anion. Very small DMSO volume concentrations (at least up to 1%) lead to enhanced paramagnetic relaxation without compromising the locally ordered domains. Larger DMSO concentrations gradually destroy these domains and reduce the effect of paramagnetic relaxation, while solvating the ions present in the mixtures. The paramagnetic relaxation was explained as a correlated combination of inner and outer-sphere mechanisms, in line with the size and structure differences between cation and anion. This study presents a robust method of characterizing paramagnetic ionic systems and obtaining a consistent analysis for a large set of samples having different co-solvent concentrations.}

Roma-Rodrigues, C, Raposo {LR }, Valente R, Fernandes {AR}, Baptista {PV}.  2021.  Combined cancer therapeutics—Tackling the complexity of the tumor microenvironment, sep. Wiley Interdisciplinary Reviews: Nanomedicine and Nanobiotechnology. 13, Number 5: John Wiley and Sons Inc. Abstract

Cancer treatment has yet to find a “silver bullet” capable of selectively and effectively kill tumor cells without damaging healthy cells. Nanomedicine is a promising field that can combine several moieties in one system to produce a multifaceted nanoplatform. The tumor microenvironment (TME) is considered responsible for the ineffectiveness of cancer therapeutics and the difficulty in the translation from the bench to bed side of novel nanomedicines. A promising approach is the use of combinatorial therapies targeting the TME with the use of stimuli-responsive nanomaterials which would increase tumor targeting. Contemporary combined strategies for TME-targeting nanoformulations are based on the application of external stimuli therapies, such as photothermy, hyperthermia or ultrasounds, in combination with stimuli-responsive nanoparticles containing a core, usually composed by metal oxides or graphene, and a biocompatible stimuli-responsive coating layer that could also contain tumor targeting moieties and a chemotherapeutic agent to enhance the therapeutic efficacy. The obstacles that nanotherapeutics must overcome in the TME to accomplish an effective therapeutic cargo delivery and the proposed strategies for improved nanotherapeutics will be reviewed. This article is categorized under: Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Emerging Technologies.

Machado, MA, Rosado LFSG, Mendes NAM, Miranda RMM, dos Santos TJG.  2021.  New directions for inline inspection of automobile laser welds using non-destructive testing, sep. The International Journal of Advanced Manufacturing Technology. AbstractWebsite

An innovative pilot installation and eddy current testing (ECT) inspection system for laser-brazed joints is presented. The proposed system detects both surface and sub-surface welding defects operating autonomously and integrated with a robotized arm. Customized eddy current probes were designed and experimentally validated detecting pore defects with 0.13 mm diameter and sub-surface defects buried 1 mm deep. The integration of the system and the manufacturing process towards an Industry 4.0 quality control paradigm is also discussed.

Saracino, F, Brinco J, Gago D, Gomes da Silva M, Ferreira RB, Ricardo-da-Silva J, Chagas R, Ferreira LM.  2021.  DCMC as a Promising Alternative to Bentonite in White Wine Stabilization. Impact on Protein Stability and Wine Aromatic Fraction, OCT. MOLECULES. 26, Number 20 Abstract
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Palion-Gazda, J, Luz A, Raposo {LR }, Choroba K, Nycz {JE }, Bieńko A, Lewińska A, Erfurt K, Baptista {PV}, Machura B, Fernandes {AR}, Shul’pina {LS }, Ikonnikov {NS }, Shul’pin {GB }.  2021.  Vanadium(IV) complexes with methyl-substituted 8-hydroxyquinolines: Catalytic potential in the oxidation of hydrocarbons and alcohols with peroxides and biological activity, oct. Molecules. 26, Number 21: MDPI - Multidisciplinary Digital Publishing Institute Abstract

Methyl-substituted 8-hydroxyquinolines (Hquin) were successfully used to synthetize five-coordinated oxovanadium(IV) complexes: [VO(2,6-(Me)2-quin)2 ] (1), [VO(2,5-(Me)2-quin)2 ] (2) and [VO(2-Me-quin)2 ] (3). Complexes 1–3 demonstrated high catalytic activity in the oxidation of hydrocarbons with H2 O2 in acetonitrile at 50◦ C, in the presence of 2-pyrazinecarboxylic acid (PCA) as a cocatalyst. The maximum yield of cyclohexane oxidation products attained was 48%, which is high in the case of the oxidation of saturated hydrocarbons. The reaction leads to the formation of a mixture of cyclohexyl hydroperoxide, cyclohexanol and cyclohexanone. When triphenylphosphine is added, cyclohexyl hydroperoxide is completely converted to cyclohexanol. Consideration of the regioand bond-selectivity in the oxidation of n-heptane and methylcyclohexane, respectively, indicates that the oxidation proceeds with the participation of free hydroxyl radicals. The complexes show moderate activity in the oxidation of alcohols. Complexes 1 and 2 reduce the viability of colorectal (HCT116) and ovarian (A2780) carcinoma cell lines and of normal dermal fibroblasts without showing a specific selectivity for cancer cell lines. Complex 3 on the other hand, shows a higher cytotoxicity in a colorectal carcinoma cell line (HCT116), a lower cytotoxicity towards normal dermal fibroblasts and no effect in an ovarian carcinoma cell line (order of magnitude HCT116 > fibroblasts > A2780).

Abdulmawjood, B, Costa B, Roma-Rodrigues C, Baptista {PV}, Fernandes {AR}.  2021.  Genetic biomarkers in chronic myeloid leukemia: What have we learned so far?, nov International Journal of Molecular Sciences. 22, Number 22: MDPI - Multidisciplinary Digital Publishing Institute Abstract

Chronic Myeloid Leukemia (CML) is a rare malignant proliferative disease of the hematopoietic system, whose molecular hallmark is the Philadelphia chromosome (Ph). The Ph chromosome originates an aberrant fusion gene with abnormal kinase activity, leading to the buildup of reactive oxygen species and genetic instability of relevance in disease progression. Several genetic abnormalities have been correlated with CML in the blast phase, including chromosomal aberrations and common altered genes. Some of these genes are involved in the regulation of cell apoptosis and proliferation, such as the epidermal growth factor receptor (EGFR), tumor protein p53 (TP53), or Schmidt-Ruppin A-2 proto-oncogene (SRC); cell adhesion, e.g., catenin beta 1(CTNNB1); or genes associated to TGF-β, such as SKI like proto-oncogene (SKIL), transforming growth factor beta 1 (TGFB1) or transforming growth factor beta 2 (TGFB2); and TNF-α pathways, such as Tumor necrosis factor (TNFA) or Nuclear factor kappa B subunit 1 (NFKB1). The involvement of miRNAs in CML is also gaining momentum, where dysregulation of some critical miRNAs, such as miRNA-451 and miRNA-21, which have been associated to the molecular modulation of pathogenesis, progression of disease states, and response to therapeutics. In this review, the most relevant genomic alterations found in CML will be addressed.

Machado, MA, Antin K-N, Rosado LS, Vilaça P, Santos TG.  2021.  High-speed inspection of delamination defects in unidirectional CFRP by non-contact eddy current testing, nov. Composites Part B: Engineering. 224:109167. AbstractWebsite

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Machado, MA, Rosado LS, Mendes NM, Miranda RM, Santos TG.  2021.  Multisensor Inspection of Laser-Brazed Joints in the Automotive Industry, nov. Sensors. 21:7335., Number 21 AbstractWebsite

Automobile laser brazing remains a complex process whose results are affected by several process variables that may result in nonacceptable welds. A multisensory customized inspection system is proposed, with two distinct non-destructive techniques: the potential drop method and eddy current testing. New probes were designed, simulated, produced, and experimentally validated in automobile's laser-brazed weld beads with artificially introduced defects. The numerical simulations allowed the development of a new four-point probe configuration in a non-conventional orthogonal shape demonstrating a superior performance in both simulation and experimental validation. The dedicated inspection system allowed the detection of porosities, cracks, and lack of bonding defects, demonstrating the redundancy and complementarity these two techniques provide.

Jesus, {AR }, Raposo {LR }, Soromenho {MRC }, Agostinho {DAS }, Esperan{\c c}a {JMSS }, Baptista {PV}, Fernandes {AR}, Reis {PM }.  2021.  New non-toxic n-alkyl cholinium-based ionic liquids as excipients to improve the solubility of poorly water-soluble drugs, nov. Symmetry. 13, Number 11: MDPI - Multidisciplinary Digital Publishing Institute Abstract

In this work, we prepared new biocompatible N-alkyl cholinium-based ionic liquids to be used as cosolvents to improve the solubility of poorly water-soluble drugs, namely, sodium diclo-fenac and paracetamol. In this set of ionic liquids, we intend to understand the effect of increasing the asymmetry of the ionic liquid cation/anion by growing the length of one of the alkyl chains attached to the nitrogen center/sulfonate center on the dissolution capacity of the ionic liquid. The addition of these new ionic liquids to water increased the dissolution capacity of the drugs up to four-times that in water, and improved the pharmacodynamic properties of these drugs, especially the case of sodium diclofenac. The intermolecular interactions between the drugs and ionic liquids were investigated by NMR. Two-dimensional1H/1H nuclear overhauser effect spectroscopy (NO-ESY) revealed an interaction between sodium diclofenac and the alaninate anion from the [C2Ch]2[SucAla]. In the case of paracetamol and [C4Ch][C2SO3], it was possible to observe two inter-molecular interactions between the hydroxyl group of paracetamol and two protons from the cation [C4Ch]+. Interestingly, the ionic liquid bearing a succinyl-DL-alaninate anion, [SucAla]2−, and a N-ethyl cholinium cation, [C2Ch]+, which presented the highest ability to dissolve sodium diclofenac, showed no cytotoxicity up to 500 mM. Therefore, this ionic liquid is a potential candidate for drug delivery applications.

Sarrato, J, Pinto AL, Malta G, Rock EH, Pina J, Lima JC, Jorge Parola A, Branco PS.  2021.  New 3-Ethynylaryl Coumarin-Based Dyes for DSSC Applications: Synthesis, Spectroscopic Properties, and Theoretical Calculations, MAY. MOLECULES. 26, Number 10 Abstract
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Kordestani, N, {Amiri Rudbari} H, Fernandes {AR}, Raposo {LR }, Luz A, Baptista {PV}, Bruno G, Scopelliti R, Fateminia Z, Micale N, Tumanov N, Wouters J, {Abbasi Kajani} A, Bordbar {AK}.  2021.  Copper(ii) complexes with tridentate halogen-substituted Schiff base ligands: synthesis, crystal structures and investigating the effect of halogenation, leaving groups and ligand flexibility on antiproliferative activities, mar. Dalton Transactions. 50:3990–4007., Number 11: RSC - Royal Society of Chemistry Abstract

To investigate the effect of different halogen substituents and leaving groups and the flexibility of ligands on the anticancer activity of copper complexes, sixteen copper(ii) complexes with eight different tridentate Schiff-base ligands containing pyridine and 3,5-halogen-substituted phenol moieties were synthesized and characterized by spectroscopic methods. Four of these complexes were also characterized by X-ray crystallography. The cytotoxicity of the complexes was determined in three different tumor cell lines (i.e.the A2780 ovarian, HCT116 colorectal and MCF7 breast cancer cell line) and in a normal primary fibroblast cell line. Complexes were demonstrated to induce a higher loss of cell viability in the ovarian carcinoma cell line (A2780) with respect to the other two tumor cell lines, and therefore the biological mechanisms underlying this loss of viability were further investigated. Complexes with ligandL1(containing a 2-pycolylamine-type motif) were more cytotoxic than complexes withL2(containing a 2-(2-pyridyl)ethylamine-type motif). The loss of cell viability in A2780 tumor cells was observed in the orderCu(Cl2-L1)NO3>Cu(Cl2-L1)Cl>Cu(Br2-L1)Cl>Cu(BrCl-L1)Cl. All complexes were able to induce reactive oxygen species (ROS) that could be related to the loss of cell viability. ComplexesCu(BrCl-L1)ClandCu(Cl2-L1)NO3were able to promote A2780 cell apoptosis and autophagy and for complexCu(BrCl-L1)Clthe increase in apoptosis was due to the intrinsic pathway.Cu(Cl2-L1)ClandCu(Br2-L1)Clcomplexes lead to cellular detachment allowing to correlate with the results of loss of cell viability. Despite the ability of theCu(BrCl-L1)Clcomplex to induce programmed cell death in A2780 cells, its therapeutic window turned out to be low making theCu(Cl2-L1)NO3complex the most promising candidate for additional biological applications.

Reigosa-Chamorro, F, Raposo {LR }, Munín-Cruz P, Pereira T}{M, Roma-Rodrigues C, Baptista {PV}, Fernandes {AR}, Vila {JM }.  2021.  In Vitro and in Vivo Effect of Palladacycles: Targeting A2780 Ovarian Carcinoma Cells and Modulation of Angiogenesis, mar. Inorganic Chemistry. 60:3939–3951., Number 6: ACS - American Chemical Society Abstract

Palladacycles are versatile organometallic compounds that show potential for therapeutic use. Here are described the synthesis and characterization of mono- and dinuclear palladacycles bearing diphosphines. Their biological effect was investigated in A2780, an ovarian-derived cancer line, and in normal dermal fibroblasts. The compounds displayed selective cytotoxicity toward the A2780 cell line. Compound 3 decreased the cell viability through cell cycle retention in G0/G1, triggered apoptosis through the intrinsic pathway, and induced autophagy in A2780 cells. Compound 9 also induced cell cycle retention, apoptosis, and cellular detachment. Notably, compound 9 induced the production of intracellular reactive oxygen species (ROS). Our work demonstrated that compound 3 enters A2780 cells via active transport, which requires energy, while compound 9 enters A2780 cells mostly passively. The potential effect of palladacycles in angiogenesis was investigated for the first time in an in vivo chorioallantoic membrane model, showing that while compound 3 displayed an antiangiogenic effect crucial to fighting cancer progression, compound 9 promoted angiogenesis. These results show that palladacycles may be used in different clinical applications where pro- or antiangiogenic effects may be desirable.

Rivas-García, L, Quiles {JL }, Roma-Rodrigues C, Raposo {LR }, Navarro-Hortal {MD }, Romero-Márquez {JM }, Esteban-Muñoz A, Varela-López A, García {LC}, Cianciosi D, {Forbes Hernández} {TY }, Battino M, Llopis J, Fernandes {AR}, Baptista {PV}, Sánchez-González C.  2021.  Rosa x hybrida extracts with dual actions: Antiproliferative effects against tumour cells and inhibitor of Alzheimer disease, mar. Food and Chemical Toxicology. 149: Elsevier Science B.V., Amsterdam. Abstract

Edible flowers are being used as a new ingredient in modern gastronomy. Recently, these products have also gained interest as an important source of phenolic compounds with potential for biomedical applications. The present work studied a methanolic extract of Rosa x hybrida in which 35 individual phenolic compounds were identified. The extract has been evaluated for its antiproliferative properties in ovarian carcinoma cells. Results showed that the antiproliferative effect was associated with the induction of autophagy and apoptosis with the concomitant ROS increase probably related to mitochondria dysfunction. These antiproliferative effects might be associated with some components of the extract such as quercetin. The extract did not induce damage in healthy cells and that it was able to improve the wound healing activity. The present study also evaluated the properties of the mentioned extract in vivo in C. elegans. Tests demonstrated a lack of toxicity in the worm model. Promising results have been obtained in transgenic strains of C. elegans that produce human beta amyloid peptide, suggesting the possible utility of the extract from the point of view of Alzheimer disease. Altogether, results suggest that Rosa x hybrida extracts could be a new tool for the development of functional foods.

Choroba, K, Machura B, Szlapa-Kula A, Malecki {JG }, Raposo L, Roma-Rodrigues C, Cordeiro S, Baptista {PV}, Fernandes {AR}.  2021.  Square planar Au(III), Pt(II) and Cu(II) complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligands: From in vitro to in vivo biological properties, jun. European Journal of Medicinal Chemistry. 218: Elsevier Masson Abstract

Cancer is the second leading cause of death worldwide. Cisplatin has challenged cancer treatment; however, resistance and side effects hamper its use. New agents displaying improved activity and more reduced side effects relative to cisplatin are needed. In this work we present the synthesis, characterization and biological activities of three complexes with quinoline-substituted 2,2′:6′,2″-terpyridine ligand: [Pt(4′-(2-quin)-terpy)Cl](SO3CF3) (1), [Au(4′-(2-quin)-terpy)Cl](PF6)2·CH3CN (2) and [Cu(4′-(2-quin)-terpy)Cl](PF6) (3). The three complexes displayed a high antiproliferative activity in ovarian carcinoma cell line (A2780) and even more noticeable in a colorectal carcinoma cell line (HCT116) following the order 3 > 2 > 1. The complexes IC50 are at least 20 × lower than the IC50 displayed by cisplatin (15.4 μM) in HCT116 cell line while displaying at the same time, much reduced cytotoxicity in a normal dermal fibroblast culture. These cytotoxic activities seem to be correlated with the inclination angles of 2-quin unit to the central pyridine. Interestingly, all complexes can interact with calf-thymus DNA (CT-DNA) in vitro via different mechanisms, although intercalation seems to be the preferred mechanism at least for 2 and 3 at higher concentrations of DNA. Moreover, circular dichroism (CD) data seems to indicate that complex 3, more planar, induces a high destabilization of the DNA double helix (shift from B-form to Z-form). Higher the deviation from planar, the lower the cytotoxicity displayed by the complexes. Cellular uptake may be also responsible for the different cytotoxicity exhibited by complexes with 3 > 2 >1. Complex 2 seems to enter cells more passively while complex 1 and 3 might enter cells via energy-dependent and -independent mechanisms. Complexes 1–3 were shown to induce ROS are associated with the increased apoptosis and autophagy. Moreover, all complexes dissipate the mitochondrial membrane potential leading to an increased BAX/BCL-2 ratio that triggered apoptosis. Complexes 2 and 3 were also shown to exhibit an anti-angiogenic effect by significantly reduce the number of newly formed blood vessel in a CAM model with no toxicity in this in vivo model. Our results seem to suggest that the increased cytotoxicity of complex 3 in HCT116 cells and its potential interest for further translation to pre-clinical mice xenografts might be associated with: 1) higher % of internalization of HCT116 cells via energy-dependent and -independent mechanisms; 2) ability to intercalate DNA and due to its planarity induced higher destabilization of DNA; 3) induce intracellular ROS that trigger apoptosis and autophagy; 4) low toxicity in an in vivo model of CAM; 5) potential anti-angiogenic effect.

Gonçalves, WB, Cervantes EP, Pádua ACCS, Santos G, Palma SICJ, Li RWC, Roque ACA, Gruber J.  2021.  Ionogels Based on a Single Ionic Liquid for Electronic Nose Application, jul. Chemosensors. 9(201), Number 8: Multidisciplinary Digital Publishing Institute AbstractPDFWebsite

Ionogel are versatile materials, as they present the electrical properties of ionic liquids and also dimensional stability, since they are trapped in a solid matrix, allowing application in electronic devices such as gas sensors and electronic noses. In this work, ionogels were designed to act as a sensitive layer for the detection of volatiles in a custom-made electronic nose. Ionogels composed of gelatin and a single imidazolium ionic liquid were doped with bare and functionalized iron oxide nanoparticles, producing ionogels with adjustable target selectivity. After exposing an array of four ionogels to 12 distinct volatile organic compounds, the collected signals were analyzed by principal component analysis (PCA) and by several supervised classification methods, in order to assess the ability of the electronic nose to distinguish different volatiles, which showed accuracy above 98%.

Raposo, {LR }, Silva {AR}, Silva D, Roma-Rodrigues C, Espadinha M, Baptista {PV}, Santos {MMM }, Fernandes {AR}.  2021.  Exploiting the antiproliferative potential of spiropyrazoline oxindoles in a human ovarian cancer cell line, jan. Bioorganic and Medicinal Chemistry. 30: Elsevier Science B.V., Amsterdam. Abstract

Cancer is still one of the deadliest diseases worldwide despite the efforts in its early detection and treatment strategies. However, most chemotherapeutic agents still present side effects in normal tissues and acquired resistance that limit their efficacy. Spiropyrazoline oxindoles might be good alternatives as they have shown antiproliferative activity in human breast and colon cancer cell lines, without eliciting cytotoxicity in healthy cells. However, their potential for ovarian cancer was never tested. In this work, the antiproliferative activity of five spiropyrazoline oxindoles was assessed in ovarian cancer cells A2780 and the biological targets and mechanism of action of the most promising compound evaluated. Compound 1a showed the highest antiproliferative effect, as well as the highest selectivity for A2780 cells compared to healthy fibroblasts. This antiproliferative effect results from the induction of cell death by mitochondria-mediated apoptosis and autophagy. In vitro DNA interaction studies demonstrated that 1a interacts with DNA by groove-binding, without triggering genotoxicity. In addition, 1a showed a strong affinity to bovine serum albumin that might be important for further inclusion in drug delivery platforms. Proteomic studies reinforced 1a role in promoting A2780 endoplasmatic reticulum (ER) stress by destabilizing the correct protein folding which triggers cell death via apoptosis and autophagy.

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