Estudo de métodos de modificação de propriedades dos glóbulos vermelhos para mimetizar efeitos da malária

Mestrado em cooperação com a Universidade do MinhoA malária mata mais de um milhão de pessoas por ano e é uma das principais causas de morte em regiões subdesenvolvidas. Assim, o desenvolvimento de técnicas de diagnós-tico rápidas, eficientes e competitivas é essencial. Este trabalho focou-se no estudo da deformabilidade dos glóbulos vermelhos (GVs) como biomarcador de malária, visto que esta propriedade do sangue está diretamente relacio-nada com as alterações que o parasita provoca ao longo da evolução da doença. Sistemas microfluídicos com estreitamentos abruptos juntamente com técnicas de processamento de imagem permitem determinar parâmetros como a velocidade de escoamento e a defor-mabilidade dos GVs. Assim, utilizando microcanais poliméricos com estreitamentos de 6 μm a 10 μm, efetuou-se um estudo comparativo entre GVs saudáveis e GVs quimica-mente modificados para aumentar a sua rigidez e mimetizar o comportamento do parasita da malária. Os resultados obtidos mostram que os GVs saudáveis se deformam natural-mente para atravessar estreitamentos e recuperam rapidamente a sua forma original após o estreitamento. Em contrapartida, nas amostras modificadas com maiores percentagens de químicos o mesmo não se verificou, ocorrendo várias oclusões. Conclui-se assim que o aumento da rigidez dos GVs provoca a diminuição da velocidade de escoamento, da deformabilidade e da capacidade de recuperação de forma das células. Este trabalho assume-se como um contributo para o desenvolvimento de novos sistemas de diagnóstico. Tendo em conta as microtecnologias existentes, será possível integrar, num chip, sensores, microeletrónica e plataformas microfluídicas, de forma a criar um método de diagnóstico simples, rápido, preciso e barato para deteção precoce da malária.Malaria kills more than one million people per year and is one of the leading causes of death in underdeveloped regions. Thus, the development of rapid, efficient and competi-tive diagnostic techniques is essential. This work focused on the study of the deformability of red blood cells (RBCs) as a malaria biomarker, since this blood property is directly related to the changes that the parasite causes throughout the course of the disease. Microfluidic systems with abrupt contrac-tions, along with image processing techniques, allow the determination of parameters such as the flow velocity and the deformability of the RBCs. Thereby, using polymeric microchannels with 6 μm to 10 μm width contractions, it was performed a comparative study between healthy and chemically modified RBCs to increase their stiffness and mimic the malaria parasite effect. The obtained results show that healthy RBCs naturally deform to cross the contractions and rapidly recover their original shape. In contrast, in modified samples with high concentration of chemicals, the same did not occur, with several occlusions being observed. Therefore, it is concluded that increasing the rigidity of the RBCs causes the decrease of the flow velocity, the deformability and the shape recovery capacity of the cells. This work is a contribution to the development of new diagnostic systems. Taking into account the existing microtechnologies, it will be possible to integrate sensors, microelectronics and microfluidic platforms into a chip, in order to create a simple, fast, accurate and low cost diagnostic method for early detection of malaria

Modifying methods of red blood cells to mimic malaria effects

A malária mata mais de um milhão de pessoas por ano e é uma das principais causas de morte em regiões subdesenvolvidas. Assim, o desenvolvimento de técnicas de diagnóstico rápidas, eficientes e competitivas é essencial. Este trabalho focou-se no estudo da deformabilidade dos glóbulos vermelhos (GVs) como biomarcador de malária, visto que esta propriedade do sangue está diretamente relacionada com as alterações que o parasita provoca ao longo da evolução da doença. Sistemas microfluídicos com estreitamentos abruptos juntamente com técnicas de processamento de imagem permitem determinar parâmetros como a velocidade de escoamento e a deformabilidade dos GVs. Assim, utilizando microcanais poliméricos com estreitamentos de 6 µm a 10 µm, efetuou-se um estudo comparativo entre GVs saudáveis e GVs quimicamente modificados para aumentar a sua rigidez e mimetizar o comportamento do parasita da malária. Os resultados obtidos mostram que os GVs saudáveis se deformam naturalmente para atravessar estreitamentos e recuperam rapidamente a sua forma original após o estreitamento. Em contrapartida, nas amostras modificadas com maiores percentagens de químicos o mesmo não se verificou, ocorrendo várias oclusões. Conclui-se assim que o aumento da rigidez dos GVs provoca a diminuição da velocidade de escoamento, da deformabilidade e da capacidade de recuperação de forma das células. Este trabalho assume-se como um contributo para o desenvolvimento de novos sistemas de diagnóstico. Tendo em conta as microtecnologias existentes, será possível integrar, num chip, sensores, microeletrónica e plataformas microfluídicas, de forma a criar um método de diagnóstico simples, rápido, preciso e barato para deteção precoce da malári

The role of the anion in imidazolium-based ionic liquids for fuel and terpenes processing

Abstract: The potentialities of methylimidazolium-based ionic liquids (ILs) as solvents were evaluated for some relevant separation problems—terpene fractionation and fuel processing—studying selectivities, capacities, and solvent performance indices. The activity coefficients at infinite dilution of the solute (1) in the IL (3), g¥ 13, of 52 organic solutes were measured by inverse gas chromatography over a temperature range of 333.2–453.2 K. The selected ILs are 1-butyl-3-methylimidazolium hexafluorophosphate, [C4mim][PF6], and the equimolar mixture of [C4mim][PF6] and 1-butyl-3-methylimidazolium chloride, [C4mim]Cl. Generally, low polar solutes follow g¥ 1,[C4mim]Cl > g¥ 1,[C4mim][PF6]+[C4mim]Cl > g¥ 1,[C4mim][PF6] while the opposite behavior is observed for alcohols and water. For citrus essential oil deterpenation, the results suggest that cations with long alkyl chains, such as [C12mim]+, promote capacity, while selectivity depends on the solute polarity. Promising results were obtained for the separation of several model mixtures relevant to fuel industries using the equimolar mixture of [C4mim][PF6] and [C4mim]Cl. This work demonstrates the importance of tailoring the polarity of the solvents, suggesting the use of ILs with mixed anions as alternative solvents for the removal of aliphatic hydrocarbons and contaminants from fuels.This research was funded by the European Regional Development Fund (ERDF) through the Regional Operational Program North 2020, within the scope of Project GreenHealth—Digital strategies in biological assets to improve well-being and promote green health, Norte-01-0145-FEDER- 000042, to which A. Zambom is thankful for her grant. S. M. Vilas-Boas thanks FCT and the European Social Fund (ESF) for his Ph.D. grant (SFRH/BD/138149/2018 and COVID/BD/152936/2022). L.P.Silva acknowledges FCT for her Ph.D. grant (SFRH/BD/135976/2018).info:eu-repo/semantics/publishedVersio

Solubility and solid phase studies of isomeric phenolic acids in pure solvents

The solubilities of gallic, protocatechuic, gentisic or α-resorcylic acids were measured in nine pure solvents (water, methanol, ethanol, 1-propanol, 2-propanol, 2-butanone, ethyl acetate, acetonitrile and dimethylformamide) at 298.15 K and 313.15 K, using the analytical isothermal shake-flask method. Additionally, solid phase studies of the selected phenolic acids were carried out using differential scanning calorimetry (DSC) and X-ray diffraction (XRD), giving access to important data on melting properties as well as on the structure of the solid phase before and after the dissolution. The NRTL-SAC model coupled to the reference solvent approach (RSA) were applied to correlate the solubility data in a set of seven solvents and, after used to predict the solubility in 1-propanol and dimethylformamide. Average relative deviations (ARD) between 28 and 40% for the correlation and between 16 and 59% for the predictions were obtained. These values are within the order of magnitude usually found for such type of semi-predictive models, using a limited set of data.This work is supported by: Project “AIProcMat@N2020 - Advanced Industrial Processes and Materials for a Sustainable Northern Region of Portugal 2020”, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF); Project POCI-01-0145-FEDER-006984 – Associate Laboratory LSRE-LCM funded by ERDF through COMPETE2020 - Programa Operacional Competitividade e Internacionalização (POCI); Project POCI-01-0145-FEDER-030463 financed by COMPETE and Portugal2020 and national funds through FCT - Fundação para a Ciência e a Tecnologia . We also acknowledge the support of CICECO – Aveiro Institute of Materials, POCI-01-0145-FEDER-007679 (Ref. FCT UID/CTM/50011/2013 ). Appendix Ainfo:eu-repo/semantics/publishedVersio

Age at onset as stratifier in idiopathic Parkinson’s disease – effect of ageing and polygenic risk score on clinical phenotypes

Several phenotypic differences observed in Parkinson’s disease (PD) patients have been linked to age at onset (AAO). We endeavoured to find out whether these differences are due to the ageing process itself by using a combined dataset of idiopathic PD (n = 430) and healthy controls (HC; n = 556) excluding carriers of known PD-linked genetic mutations in both groups. We found several significant effects of AAO on motor and non-motor symptoms in PD, but when comparing the effects of age on these symptoms with HC (using age at assessment, AAA), only positive associations of AAA with burden of motor symptoms and cognitive impairment were significantly different between PD vs HC. Furthermore, we explored a potential effect of polygenic risk score (PRS) on clinical phenotype and identified a significant inverse correlation of AAO and PRS in PD. No significant association between PRS and severity of clinical symptoms was found. We conclude that the observed non-motor phenotypic differences in PD based on AAO are largely driven by the ageing process itself and not by a specific profile of neurodegeneration linked to AAO in the idiopathic PD patients

Desenvolvimento de um simulador de laparoscopia

Com base no simulador de laparoscopia existente no hospital de Bragança foi proposto o desenvolvimento de um novo que incluísse novas formas de manuseamento e que incluísse atratividade para tornar o treino dos profissionais mais preciso. Exteriormente, a portabilidade foi assegurada pela escolha de uma mala leve e compacta, que permite não só a arrumação mas o transporte para a sala de simulação ou até para um local diferente do de origem. Esta mala, pintada de branco para uma melhor deteção de sujidades, é o próprio simulador, sendo adaptada para diferentes alturas consoante o treino exigido ao profissional de saúde. Na sua tampa foram realizados três furos, dois para a introdução das pinças e um para a câmara. A simulação torna-se mais prática uma vez que o simulador assegura que todos os circuitos de treino são montados numa única peça. A mala escolhida permite ainda que os recursos de treino estejam guardados, prevenindo danos ou perdas. Na base da mala podem ainda ser realizados treinos em órgãos animais, pois esta é facilmente lavável. As bases de treino estão colocadas sob um circuito elétrico onde qualquer erro cometido pelos profissionais, ou falha nas regras do nível, faz acender uma luz e posteriormente provoca o acionamento de um aviso sonoro. A base de treino é em cobre para garantir condutividade elétrica. Este sistema é baseado no sistema do Busca-Pólos, onde um pólo está ligado à pinça e outro pólo à placa de cobre e que, quando em contacto, acionam o sistema eléctrico.info:eu-repo/semantics/publishedVersio

Imaging of healthy and malaria-mimicked red blood cells in polydimethylsiloxane microchannels for determination of cells deformability and flow velocity

Imaging analysis techniques have been extensively used to obtain crucial information on blood phenomena in the microcirculation. In the present study, it is intended to mimic the effects of malaria on the red blood cells (RBCs), by changing their properties using a different concentration of glutaraldehyde solution. The effects of the disease in stiffing RBCs were evaluated using polydimethylsiloxane microchannels that comprise contractions with 10 µm width and measuring the cells deformability and the flow velocity in healthy and modified conditions. The obtained results show a decrease in the RBCs deformability and in the flow velocity with the presence of glutaraldehyde, when compared to the behavior of healthy RBCs samples. Therefore, it can be concluded that, using image analysis (ImageJ & PIVLab), it is possible to measure the deformability of the RBCs and the flow velocity and, consequently, obtaining a correlation between the difference of velocities/deformabilities in the microchannels. In the future, this correlation can be used to relate the RBCs behavior with the various stages of malaria. This study can be a starting point for establishing the development of new malaria diagnostic systems towards point-of-care lab-on-a-chip devices.This work was supported by FCT with the reference project UID/EEA/04436/2013, by FEDER funds through the COMPETE 2020 – Programa Operacional Competitividade e Internacionalização (POCI) with the reference project POCI-01- 0145-FEDER- 006941. S.O. Catarino thanks the FCT for the SFRH/BPD/108889/2015 grant, supported by national funds from Ministérios da Ciência, Tecnologia e Ensino Superior and by FSE through the POCH - Programa Operacional Capital Humano. The authors thank Diana Pinho from the IP Bragança for providing the blood samples and for the support in the experimental tests.info:eu-repo/semantics/publishedVersio

Liquefying flavonoids with terpenoids through deep eutectic solvent formation

The formation of deep eutectic solvents (DES) is tied to negative deviations to ideality caused by the establishment of stronger interactions in the mixture than in the pure DES precursors. This work tested thymol and menthol as hydrogen bond donors when combined with different flavonoids. Negative deviations from ideality were observed upon mixing thymol with either flavone or flavanone, two parent flavonoids that only have hydrogen bond acceptor (HBA) groups, thus forming non-ionic DES (Type V). On the other hand, the menthol systems with the same compounds generally showed positive deviations from ideality. That was also the case with the mixtures containing the more complex hydroxylated flavonoid, hesperetin, which resulted in positive deviations when mixed with either thymol or menthol. COSMO-RS successfully predicted the behavior of the solid-liquid phase diagram of the studied systems, allowing for evaluation of the impact of the different contributions to the intermolecular interactions, and proving to be a good tool for the design of DES.This research was developed within the scope of the project CICECO-Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020, and LA/P/0006/2020, and project CIMO-Mountain Research Center, UIDB/00690/2020 and LA/P/0007/2020, financed by national funds through the Portuguese Foundation for Science and Technology/MCTES. Support was also provided by project AllNat—POCI-01-0145-FEDER-030463 (PTDC/EQU-EPQ/30463/2017), funded by FEDER funds through COMPETE2020—Prog. Operacional Competitividade e Internacionalização (POCI), and by national funds through the Foundation for Science and Technology (FCT/MCTES). This work was supported by the Fundacão para a Ciência e Tecnologia (FCT) (funded by national funds through the FCT/MCTES (PIDDAC)) to CIQUP, Faculty of Science, University of Porto (Project UIDB/00081/2020), IMS-Institute of Molecular Sciences (LA/P/0056/2020)). A.I.M.C.L.F. is financed by national funds through the FCT-I.P., in the framework of the execution of the program contract provided in paragraphs 4, 5, and 6 of art. 23 of Law no. 57/2016 of 29 August, as amended by Law no. 57/2017 of 19 July. G.T. and S.M.V.B. acknowledge FCT/MCTES for the Ph.D. grants UI/BD/151114/2021 and SFRH/BD/138149/ 2018, respectively.info:eu-repo/semantics/publishedVersio

Red para la innovación en la selvicultura y los sistemas de integración de riesgos en la gestión forestal

La forêt, en plus de ses fonctions économiques reconnues par tous les acteurs du milieu rural tels que le développement de l'emploi rural et le marché local du bois pour la transformation ou pour l'énergie, rend de nombreux autres services. Cependant, de multiples risques sont identifiables et doivent être gérés dans et pourront éventuellement être aggravés par les changements climatiques: futures sécheresses favorables aux pathogènes et ravageurs ainsi qu'à la propagation des incendies, et le risque de la modification du vent. Le projet FORRISK se focalisera ainsi sur les risques en forêt dont l'intensité est modulée par le changement climatique. L'histoire des forêts du sud de l'Europe nous rappelle que pour de nombreux problèmes, une approche seulement nationale n'a pas de sens. C'est-à-dire, les risques concernés, les réponses à apporter peuvent être soit au niveau technique soit au niveau de l'organisation des institutions. Pour cette raison, FORRISK vise à coordonner et mettre en réseau trois communautés différentes que sont les acteurs politiques, les gestionnaires et les scientifiques, dans le but d'obtenir que la gestion des risques soit partie intégrante des décisions prises à tous les niveaux du secteur forestier. Cela permettra d'initier une plateforme européenne sur les risques forestiers en facilitant des recommandations et des informations pertinentes à tous les niveaux. Pour y parvenir, le projet analysera et comparera les outils institutionnels, les systèmes et organisations liés à la gestion de risques dans les régions étudiées. Ensuite, FORRISK développera sur le terrain des techniques de lutte écologique, génétique et sylvicole, dont les résultats feront l'objet de guides de bonne pratique. Les outils produits consisteront à des cartes de risques à l'échelle régionale ou subrégionale, ainsi que à des modèles informatiques permettant de faire des diagnostics sur le terrain et de modéliser la propagation du fomès dans les peuplements de pin maritime. Ainsi, décideurs politiques, gestionnaires et scientifiques auront entre leurs mains des outils adaptés à la gestion de nombreux risques menaçant la forêt dans leurs régions