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2021
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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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.
Ramanaiaha, SV, Cordas CM, Matias SC, Reddyd MV, Leitão JH, Fonseca LP.  2021.  Bioelectricity generation using long-term operated biocathode: RFLP based microbial diversity analysis. Biotechnology Reports. 32:e00693.
C.M., C, J.J.G. M, A. E, R. M.  2021.  Carbon dioxide utilisation - bioelectrochemical approaches. Enzymes for Solving Humankind's Problems, Moura J.J.G., Moura I., Maia L.B. (eds). :83-108.
Oliveira, RD, Mouquinho A, Centeno P, Alexandre M, Haque S, Martins R, Fortunato E, Águas H, Mendes MJ.  2021.  Colloidal Lithography for Photovoltaics: An Attractive Route for Light Management. Nanomaterials. 11(7):1665.
Silva, PES, da Rosa RR, Chagas R, Fernandes SN, Godinho MH.  2021.  Colourful Patterns in Cellulose-Based Liquid Crystals. Liquid Crystals and their Application. 21(4):53-60.412702article_2021_21_4_53-60.pdf
Fernandes, H, Maia L, Ribeiro PM, J.J.G. M, Cerqueira NM.  2021.  The complete catalytic mechanism of Xanthine Oxidase: a computational study. Inorg Chem Front. 8:405.
Costa, FB, Machado MA, Bonfait GJ, Vieira P, Santos TG.  2021.  Continuous wave terahertz imaging for NDT: Fundamentals and experimental validation. Measurement. 172(108904) AbstractWebsite

Continuous wave terahertz (CW THz) imaging, is a variant of terahertz imaging that has been gaining scientific
and technological relevance in multiple areas. In this paper the fundamental phenomena of CW THz were
studied and a mathematical model was developed that successfully describes the Fabry–Perot interference for
such a system, opening the possibility for measurement of thicknesses and surface curvatures. The capabilities
of the system were tested using different types of defects, such as voids, water infiltrations and thin metallic
wires. The interactions between different materials, features and the radiation beam were numerically studied
using finite element method and the results agreed with the experiments. By comparing the results with other
Non-Destructive Testing methods, it was found that CW THz imaging is particularly interesting to image water
infiltrations and composite materials that incorporate conductive wires.

Carlos, E, Deuermeier J, Branquinho R, Gaspar C, Martins R, Kiazadeh A, Fortunato E.  2021.  Design and synthesis of low temperature printed metal oxide memristors. Materials Chemistry C. 9:3911–3918.
Saif, HM, Huertas RM, Pawlowski S, Crespo JG, Velizarov S.  2021.  Development of highly selective composite polymeric membranes for Li+/ Mg2+ separation. Journal of Membrane Science. 620:118891.Website
Hovhannisyan, V, Siposova K, Musatov A, Chen S-J.  2021.  Development of Multifunctional Nanocomposites for Controlled Drug Delivery and Hyperthermia. Scientific Reports. 11(5528)
Rajnak, M, Dolnik B, Hodermarsky P, Paulovicova K, Cimbala R, Timko M, Kopcansky P.  2021.  Dynamic Magnetic Response of Ferrofluids under a Static Electric Field. Physics of Fluids. 33(082006)
Schuster, CS, Crupi I, Halme J, Koç M, Mendes MJ, Peters IM, Yerci S.  2021.  Empowering Photovoltaics with Smart Light Management Technologies. Handbook of Climate Change Mitigation and Adaptation. :1-84., New York: Springer
Menda, UD, Ribeiro G, Nunes D, Calmeiro T, Águas H, Fortunato E, Martins R, Mendes MJ.  2021.  High-performance wide bandgap perovskite solar cells fabricated in ambient high-humidity conditions. Materials Advances. 2(19):6344-6355.
Ramanaiah, SV, Cordas CM, Matiasand S, Fonseca LP.  2021.  In Situ Electrochemical Characterization of a Microbial Fuel Cell Biocathode Running on Wastewater. Catalysts. 11:839.
Carrêlo, H, Soares PIP, Borges JB, Cidade MT.  2021.  Injectable Composite Systems Based on Microparticles in Hydrogels for Bioactive Cargo Controlled Delivery. Gels. 7(3):147. AbstractWebsite

Engineering drug delivery systems (DDS) aim to release bioactive cargo to a specific site within the human body safely and efficiently. Hydrogels have been used as delivery matrices in different studies due to their biocompatibility, biodegradability, and versatility in biomedical purposes. Microparticles have also been used as drug delivery systems for similar reasons. The combination of microparticles and hydrogels in a composite system has been the topic of many research works. These composite systems can be injected in loco as DDS. The hydrogel will serve as a barrier to protect the particles and retard the release of any bioactive cargo within the particles. Additionally, these systems allow different release profiles, where different loads can be released sequentially, thus allowing a synergistic treatment. The reported advantages from several studies of these systems can be of great use in biomedicine for the development of more effective DDS. This review will focus on in situ injectable microparticles in hydrogel composite DDS for biomedical purposes, where a compilation of different studies will be analysed and reported herein.

Delgado, B, Carrêlo H, Loureiro MV, Marques AC, Borges JB, Cidade MT.  2021.  Injectable hydrogels with two different rates of drug release based on pluronic/water system filled with poly(ε-caprolactone) microcapsules. Journal of Materials Science. 56:13416-13428. AbstractWebsite

The present paper regards the preparation and characterization of Pluronic F127 + F68/water/poly (ε-caprolactone) microcapsules (MCs) composite systems for tissue repair. The first part of the work relates to the production of poly(ε-caprolactone) (PCL) MCs via water-in-oil-in-water (W/O/W) double emulsion system combined with solvent evaporation method. The study of different process parameters in the final MCs characteristics and their drug release profile is herein reported. Different percentages of PCL, emulsion stabilizer, and volume proportions of the emulsion constituents have been tested, leading to considerable differences in the MCs size distributions. The selected MCs, containing an aqueous solution of methylene blue (MB) as a model drug, were then used to fill a Pluronic F127 + F68/water system leading to the final composite system (5 and 10 wt % MB loaded PCL MCs). The composite systems were characterised in the second part of the work in terms of its rheological behaviour and drug release performance. They were found to gellify at 30 °C, and present an extended drug release to a total of 18 days. The models that best define the release profiles were also studied, with the release of MB occurring mostly by Fick diffusion and polymer chain relaxation. Pluronic F127 + F68/water/poly (ε-caprolactone) MCs composite system is shown to be a promising injectable system, with two different drug release rates, for tissue repair.

Mendes, D, Sousa D, Cerdeira AC, Pereira LCJ, Marques A, Murta-Pina J, Pronto A, Ferreira I.  2021.  Low-cost and high-performance 3D printed YBCO superconductors. Ceramics International. 47:381-387.
Santos, R, Romão MJ, Roque ACA, Carvalho AL.  2021.  Magnetic particles used in a new approach for designed protein crystallization. CrystEngComm. 23(5):1083-1090.
Gigante, AM, Olivença F, Catalão MJ, Moniz-Pereira J, Filipe SR, Pimentel M.  2021.  The Mycobacteriophage Ms6 LysB N-terminus Displays Peptidoglycan Binding Affinity. Viruses. 13(7):1377.
Teixeira, SS, Graça MPF, Lucas J, Valente MA, Soares PIP, Lança MC, Vieira T, Silva JC, Borges JP, Jinga L-I, Socol G, Salgueiro CM, Nunes J, Costa LC.  2021.  Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine. Nanomaterials. 11(1):193. AbstractWebsite

The physical properties of the cubic and ferrimagnetic spinel ferrite LiFe5O8 has made it an attractive material for electronic and medical applications. In this work, LiFe5O8 nanosized crystallites were synthesized by a novel and eco-friendly sol-gel process, by using powder coconut water as a mediated reaction medium. The dried powders were heat-treated (HT) at temperatures between 400 and 1000 °C, and their structure, morphology, electrical and magnetic characteristics, cytotoxicity, and magnetic hyperthermia assays were performed. The heat treatment of the LiFe5O8 powder tunes the crystallite sizes between 50 nm and 200 nm. When increasing the temperature of the HT, secondary phases start to form. The dielectric analysis revealed, at 300 K and 10 kHz, an increase of ε′ (≈10 up to ≈14) with a tanδ almost constant (≈0.3) with the increase of the HT temperature. The cytotoxicity results reveal, for concentrations below 2.5 mg/mL, that all samples have a non-cytotoxicity property. The sample heat-treated at 1000 °C, which revealed hysteresis and magnetic saturation of 73 emu g−1 at 300 K, showed a heating profile adequate for magnetic hyperthermia applications, showing the potential for biomedical applications.