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2021
Ferreira-Silva, M, Faria-Silva C, Baptista {PV}, Fernandes E, Fernandes {AR}, Corvo {ML}.  2021.  Liposomal nanosystems in rheumatoid arthritis, apr. Pharmaceutics. 13, Number 4: MDPI AG Abstract

Rheumatoid arthritis (RA) is an autoimmune disease that affects the joints and results in reduced patient quality of life due to its chronic nature and several comorbidities. RA is also associated with a high socioeconomic burden. Currently, several available therapies minimize symptoms and prevent disease progression. However, more effective treatments are needed due to current therapies’ severe side-effects, especially under long-term use. Drug delivery systems have demonstrated their clinical importance—with several nanocarriers present in the market—due to their capacity to improve therapeutic drug index, for instance, by enabling passive or active targeting. The first to achieve market authorization were liposomes that still represent a considerable part of approved delivery systems. In this manuscript, we review the role of liposomes in RA treatment, address preclinical studies and clinical trials, and discuss factors that could hamper a successful clinical translation. We also suggest some alterations that could potentially improve their progression to the market.

Isufi, B, Marreiros R, Ramos AP, Lúcio V.  2021.  Comportamento sísmico da ligação laje-pilar considerando diferentes soluções de reforço, 3-5 November. Reabilitar & Betão Estrutural 2020. , Lisbonfullpaperbe2020_pt_final.pdf
Rossi, M, Isufi B, Ramos AP.  2021.  Comportamento sísmico de ligações laje-pilar com variação da taxa de armadura de flexão, 3-5 November. Reabilitar & Betão Estrutural 2020. , Lisbon
Fialho, L, Araújo D, Alves VD, Roma-Rodrigues C, Baptista PV, Fernandes AR, Freitas F, Reis MAM.  2021.  Cation-mediated gelation of the fucose-rich polysaccharide FucoPol: preparation and characterization of hydrogel beads and their cytotoxicity assessment, 2021. International Journal of Polymeric Materials and Polymeric Biomaterials. 70(2):90-99. AbstractWebsite
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Brás, NF, Neves RPP, Lopes FAA, Correia MAS, Palma AS, Sousa SF, Ramos MJ.  2021.  Combined in silico and in vitro studies to identify novel antidiabetic flavonoids targeting glycogen phosphorylase, 2021. 108:104552. AbstractWebsite

Novel pharmacological strategies for the treatment of diabetic patients are now focusing on inhibiting glycogenolysis steps. In this regard, glycogen phosphorylase (GP) is a validated target for the discovery of innovative antihyperglycemic molecules. Natural products, and in particular flavonoids, have been reported as potent inhibitors of GP at the cellular level. Herein, free-energy calculations and microscale thermophoresis approaches were performed to get an in-depth assessment of the binding affinities and elucidate intermolecular interactions of several flavonoids at the inhibitor site of GP. To our knowledge, this is the first study indicating genistein, 8-prenylgenistein, apigenin, 8-prenylapigenin, 8-prenylnaringenin, galangin and valoneic acid dilactone as natural molecules with high inhibitory potency toward GP. We identified: i) the residues Phe285, Tyr613, Glu382 and/or Arg770 as the most relevant for the binding of the best flavonoids to the inhibitor site of GP, and ii) the 5-OH, 7-OH, 8-prenyl substitutions in ring A and the 4′-OH insertion in ring B to favor flavonoid binding at this site. Our results are invaluable to plan further structural modifications through organic synthesis approaches and develop more effective pharmaceuticals for Type 2 Diabetes treatment, and serve as the starting point for the exploration of food products for therapeutic usage, as well as for the development of novel bio-functional food and dietary supplements/herbal medicines.

Raposo, LR, Silva A, 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, 2021. Bioorganic & Medicinal Chemistry. 30:115880. AbstractWebsite

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.

Lapão, LV, Peyroteo M, Maia M, Seixas J, Gregório J, Mira da Silva M, Heleno B, Correia JC.  2021.  Implementation of Digital Monitoring Services During the COVID-19 Pandemic for Patients With Chronic Diseases: Design Science Approach, 2021. JMIR. 23(8):e24181. AbstractWebsite

Background: The COVID-19 pandemic is straining health systems and disrupting the delivery of health care services, in particular, for older adults and people with chronic conditions, who are particularly vulnerable to COVID-19 infection. Objective: The aim of this project was to support primary health care provision with a digital health platform that will allow primary care physicians and nurses to remotely manage the care of patients with chronic diseases or COVID-19 infections. Methods: For the rapid design and implementation of a digital platform to support primary health care services, we followed the Design Science implementation framework: (1) problem identification and motivation, (2) definition of the objectives aligned with goal-oriented care, (3) artefact design and development based on Scrum, (4) solution demonstration, (5) evaluation, and (6) communication. Results: The digital platform was developed for the specific objectives of the project and successfully piloted in 3 primary health care centers in the Lisbon Health Region. Health professionals (n=53) were able to remotely manage their first patients safely and thoroughly, with high degrees of satisfaction. Conclusions: Although still in the first steps of implementation, its positive uptake, by both health care providers and patients, is a promising result. There were several limitations including the low number of participating health care units. Further research is planned to deploy the platform to many more primary health care centers and evaluate the impact on patient’s health related outcomes.

Mota, C, Diniz A, Coelho C, Santos-Silva T, Esmaeeli M, Leimkühler S, Cabrita EJ, Marcelo F, Romão MJ.  2021.  Interrogating the Inhibition Mechanisms of Human Aldehyde Oxidase by X-ray Crystallography and NMR Spectroscopy: The Raloxifene Case, 2021. Journal of Medicinal ChemistryJournal of Medicinal Chemistry. : American Chemical Society AbstractWebsite

Human aldehyde oxidase (hAOX1) is mainly present in the liver and has an emerging role in drug metabolism, since it accepts a wide range of molecules as substrates and inhibitors. Herein, we employed an integrative approach by combining NMR, X-ray crystallography, and enzyme inhibition kinetics to understand the inhibition modes of three hAOX1 inhibitors—thioridazine, benzamidine, and raloxifene. These integrative data indicate that thioridazine is a noncompetitive inhibitor, while benzamidine presents a mixed type of inhibition. Additionally, we describe the first crystal structure of hAOX1 in complex with raloxifene. Raloxifene binds tightly at the entrance of the substrate tunnel, stabilizing the flexible entrance gates and elucidating an unusual substrate-dependent mechanism of inhibition with potential impact on drug–drug interactions. This study can be considered as a proof-of-concept for an efficient experimental screening of prospective substrates and inhibitors of hAOX1 relevant in drug discovery.Human aldehyde oxidase (hAOX1) is mainly present in the liver and has an emerging role in drug metabolism, since it accepts a wide range of molecules as substrates and inhibitors. Herein, we employed an integrative approach by combining NMR, X-ray crystallography, and enzyme inhibition kinetics to understand the inhibition modes of three hAOX1 inhibitors—thioridazine, benzamidine, and raloxifene. These integrative data indicate that thioridazine is a noncompetitive inhibitor, while benzamidine presents a mixed type of inhibition. Additionally, we describe the first crystal structure of hAOX1 in complex with raloxifene. Raloxifene binds tightly at the entrance of the substrate tunnel, stabilizing the flexible entrance gates and elucidating an unusual substrate-dependent mechanism of inhibition with potential impact on drug–drug interactions. This study can be considered as a proof-of-concept for an efficient experimental screening of prospective substrates and inhibitors of hAOX1 relevant in drug discovery.

Ali, MS, Muthukumaran J, Jain M, Santos-Silva T, Al-Lohedan HA, Al-Shuail NS.  2021.  Molecular interactions of cefoperazone with bovine serum albumin: Extensive experimental and computational investigations, 2021. 337:116354. AbstractWebsite

We investigated the binding of the cephalosporin-class drug cefoperazone (CFP) with bovine serum albumin (BSA) using spectroscopic techniques and in silico methods. The aim of this study was to (i) emphasize the importance of correcting for the inner filter effect in this type of study and (ii) understand the binding mechanism of CFP with BSA by addressing protein conformation and plausible binding sites. Formation of the complex was confirmed by UV–visible spectroscopy. Quenching of BSA fluorescence in the presence of CFP was also observed. Because of the high absorption of CFP in the fluorescence emission range of BSA, the fluorescence emission spectra were corrected for the inner filter effect. Fluorescence emission was studied at excitation wavelengths of 280 and 295 nm. The uncorrected data showed a significant contribution of tyrosine at the excitation wavelength of 280 nm; however, after correction, this contribution became negligible. The static-type mechanism was found to be involved in quenching, with almost 1:1 binding between BSA and CFP. Hydrogen bonding and hydrophobic forces were found to dominate the protein–ligand interactions with a slight decrease in the α-helical contents. Synchronous fluorescence spectral data (at Δλ = 15 and 60 nm) were also corrected for the inner filter effect, with the results being similar to those of excitation at 280 and 295 nm. Molecular docking and molecular dynamics (MD) simulation results suggest that, apart from the two known drug binding sites (drug site I and II), one putative binding site (binding site III) located between BSA domains 1 and 3 was also possible for CFP. MD simulations of the previously reported drug binding sites (drug site I and II) and putative binding site III revealed that binding site III showed excellent binding profiles and could be a target for future research related to BSA-drug binding.

Sine, A, Pimentel M, Nunes S.  2021.  Punching Shear Tests on RC Flat Slabs Strengthened with an UHPFRC Layer, 2021. fib Symposium 2021. , Lisbonsine-fib2021_169_punching.pdf
Pimentel, M, Sine A, Nunes S.  2021.  Resistência ao punçoamento de lajes fungiformes reforçadas com UHPFRC, 2021. Reabilitar & Betão Estrutural 2020. , Lisbonrbe2020_artigo_puncoamento_1.pdf
Goodfellow, BJ, Freire F, Carvalho AL, Aveiro SS, Charbonnier P, Moulis J-M, Delgado L, Ferreira GC, Rodrigues JE, Poussin-Courmontagne P, Birck C, McEwen A, Macedo AL.  2021.  The SOUL family of heme-binding proteins: Structure and function 15 years later, 2021. 448:214189. AbstractWebsite

The SOUL, or heme-binding protein HBP/SOUL, family represents a group of evolutionary conserved putative heme-binding proteins that contains a number of members in animal, plant andbacterial species. The structures of the murine form of HEBP1, or p22HBP, and the human form of HEBP2, or SOUL, have been determined in 2006 and 2011 respectively. In this work we discuss the structures of HEBP1 and HEBP2 in light of new X-ray data for heme bound murine HEBP1. The interaction between tetrapyrroles and HEBP1, initially proven to be hydrophobic in nature, was thought to also involve electrostatic interactions between heme propionate groups and positively charged amino acid side chains. However, the new X-ray structure, and results from murine HEBP1 variants and human HEBP1, confirm the hydrophobic nature of the heme-HEBP1 interaction, resulting in Kd values in the low nanomolar range, and rules out any electrostatic stabilization. Results from NMR relaxation time measurements for human HEBP1 describe a rigid globular protein with no change in motional regime upon heme binding. X-ray structures deposited in the PDB for human HEBP2 are very similar to each other and to the new heme-bound murine HEBP1 X-ray structure (backbone rmsd ca. 1 Å). Results from a HSQC spectrum centred on the histidine side chain Nδ-proton region for HEBP2 confirm that HEBP2 does not bind heme via H42 as no chemical shift differences were observed upon heme addition for backbone NH and Nδ protons. A survey of the functions attributed to HEBP1 and HEBP2 over the last 20 years span a wide range of cellular pathways. Interestingly, many of them are specific to higher eukaryotes, particularly mammals and a potential link between heme release under oxidative stress and human HEBP1 is also examined using recent data. However, at the present moment, trying to relate function to the involvement of heme or tetrapyrrole binding, specifically, makes little sense with our current biological knowledge and can only be applied to HEBP1, as HEBP2 does not interact with heme. We suggest that it may not be justified to call this very small family of proteins, heme-binding proteins. The family may be more correctly called “the SOUL family of proteins related to cellular fate” as, even though only HEBP1 binds heme tightly, both proteins may be involved in cell survival and/or proliferation.

Lima, CDL, Coelho H, Gimeno A, Trovão F, Diniz A, Dias JS, Jiménez-Barbero J, Corzana F, Carvalho AL, Cabrita EJ, Marcelo F.  2021.  Structural insights into the molecular recognition mechanism of the cancer and pathogenic epitope, LacdiNAc by immune-related lectins, 2021. Chemistry – A European JournalChemistry – A European Journal. n/a(n/a): John Wiley & Sons, Ltd AbstractWebsite

Interactions of glycan-specific epitopes to human lectin receptors represent novel immune checkpoints for investigating cancer and infection diseases. By employing a multidisciplinary approach that combines isothermal titration calorimetry, NMR spectroscopy, molecular dynamics simulations, and X-ray crystallography, we disclosed the molecular determinants that govern the recognition of the tumour and pathogenic glycobiomarker LacdiNAc (GalNAc?1-4GlcNAc, LDN), including their comparison with the ubiquitous LacNAc epitope (Gal?1-4GlcNAc, LN), by two human immune-related lectins, galectin-3 (hGal-3) and the macrophage galactose C-type lectin (hMGL). A different mechanism of binding and interactions is observed for the hGal-3/LDN and hMGL/LDN complexes, which explains the remarkable difference in the binding specificity of LDN and LN by these two lectins. The new structural clues reported herein are fundamental for the chemical design of mimetics targeting hGal-3/hMGL recognition process.

Silva, PES, Chagas R, Fernandes SN, Pieranski P, Selinger RLB, Godinho MH.  2021.  Travelling colourful patterns in self-organized cellulose-based liquid crystalline structures, 2021. 2(1):79. AbstractWebsite

Cellulose-based systems are useful for many applications. However, the issue of self-organization under non-equilibrium conditions, which is ubiquitous in living matter, has scarcely been addressed in cellulose-based materials. Here, we show that quasi-2D preparations of a lyotropic cellulose-based cholesteric mesophase display travelling colourful patterns, which are generated by a chemical reaction-diffusion mechanism being simultaneous with the evaporation of solvents at the boundaries. These patterns involve spatial and temporal variation in the amplitude and sign of the helix´s pitch. We propose a simple model, based on a reaction-diffusion mechanism, which simulates the observed spatiotemporal colour behaviour.

Kumar, A, Cruz C, Figueirinhas JL, Sebastião PJ, Trindade AC, Fernandes SN, Godinho MH, Fossum JO.  2021.  Water Dynamics in Composite Aqueous Suspensions of Cellulose Nanocrystals and a Clay Mineral Studied through Magnetic Resonance Relaxometry, 2021. The Journal of Physical Chemistry BThe Journal of Physical Chemistry B. 125(46):12787-12796.: American Chemical Society AbstractWebsite
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Rossi, M, Isufi B, Ramos AP.  2021.  Seismic behavior of slab-column connections with varying flexural reinforcement ratio, 14-16 June 2021. fib Symposium 2021. , Lisbon
Isufi, B, Marreiros R, Ramos AP, Lúcio V.  2021.  Seismic behaviour of slab – column connections with various punching shear enhancement methods, 14-16 June 2021. fib Symposium 2021. , Lisbon
Silva, MA, Portela PC, Salgueiro CA.  2021.  Rational design of electron/proton transfer mechanisms in the exoelectrogenic bacteria Geobacter sulfurreducens, 07. Biochemical Journal. 478:2871-2887., Number 14 AbstractWebsite

{The redox potential values of cytochromes can be modulated by the protonation/deprotonation of neighbor groups (redox-Bohr effect), a mechanism that permits the proteins to couple electron/proton transfer. In the respiratory chains, this effect is particularly relevant if observed in the physiological pH range, as it may contribute to the electrochemical gradient for ATP synthesis. A constitutively produced family of five triheme cytochromes (PpcA−E) from the bacterium Geobacter sulfurreducens plays a crucial role in extracellular electron transfer, a hallmark that permits this bacterium to be explored for several biotechnological applications. Two members of this family (PpcA and PpcD) couple electron/proton transfer in the physiological pH range, a feature not shared with PpcB and PpcE. That ability is crucial for G. sulfurreducens’ growth in Fe(III)-reducing habitats since extra contributors to the electrochemical gradient are needed. It was postulated that the redox-Bohr effect is determined by the nature of residue 6, a leucine in PpcA/PpcD and a phenylalanine in PpcB/PpcE. To confirm this hypothesis, Phe6 was replaced by leucine in PpcB and PpcE. The functional properties of these mutants were investigated by NMR and UV–visible spectroscopy to assess their capability to couple electron/proton transfer in the physiological pH range. The results obtained showed that the mutants have an increased redox-Bohr effect and are now capable of coupling electron/proton transfer. This confirms the determinant role of the nature of residue 6 in the modulation of the redox-Bohr effect in this family of cytochromes, opening routes to engineer Geobacter cells with improved biomass production.}

Henriques, JT.  2021.  1D Fiber-shaped supercapacitors. FCT NOVA.
Mendes, DNDL, Gaspar A, Ferreira I, Mota JPB, Ribeiro RPPL.  2021.  3D-printed hybrid zeolitic/carbonaceous electrically conductive adsorbent structures. Chemical Engineering Research and Design. 174:442-453.
Pina, AS, Batalha IL, Dias AMGC, Roque ACA.  2021.  Affinity tags in protein purification and peptide enrichment: An overview, in Protein Downstream Processing: Design, Development, and Application of High and Low-Resolution Methods. Methods in Molecular Biology. :107-132.: Springer-Humana Press
Fernandes, CSM, Pina AS, Roque ACA.  2021.  Affinity-triggered hydrogels: Developments and prospects in biomaterials science. Biomaterials. 268:120563.
Gavinho, SR, Graça MP, Prezas P, Borges JB, Silva JC, Pires E, Armês H, Coucelo J.  2021.  Antibacterial bioglass in dental implants: a canine clinical study. European Journal of Public Health. 31(Supplement_2):ckab120.006. AbstractWebsite

Background
Peri-implantitis is considered the most challenging biological complication in implantology, as untreated disease can progress and result in implant loss. Therefore, disease prevention is crucial in daily clinical practice. It has been reported that the use of bioactive glass, as an implant coating, can stimulate tissue integration and accelerate tissue regeneration. Besides these properties, it is possible to promote bacterial activity by inserting silver into the bioglass

Methods
Bioglass with composition 45S5 was synthesised by the fusion method, replacing the amount of Na2CO3 by AgNO3 (BG 2% wt). The implants were resealed by the CoBlast® technique. Clinical cases with pathology of the mandible/maxilla were selected and implants dimensioned for the canine bone structure were applied.

Results
Three months after implantation, imaging exams, namely CT scans, showed no signs of early rejection by septic or cytotoxic loss. No decrease or loss of peri-implant bone was observed. In all cases the implants remained without signs of instability, and with sufficient support for the application of the exo-prosthesis or dental crown. The results of histological analysis showed no signs of infection or osteolysis. The zone of peri-implant fibrosis was not observable in the samples, showing a good evolution in implant osteointegration.

Conclusions
The results show promising evidences for the use of this biomaterial as a coating, since aseptic rejection, later on, and that related to the shape and biomaterials used in the implant's design, usually begins during the first 3 months.

Mariz, BP, Carvalho S, Batalha IL, Pina AS.  2021.  Artificial enzymes bringing together computational design and directed evolution. Organic & Biomolecular Chemistry. 19(9):1915-1925.