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- 1,6-Conjugate Additions of Carbon Nucleophiles to 2-[(1E,3E)-4-Arylbuta-1,3-dien-1-yl]-4H-chromen-4-onesPublication . Albuquerque, Hélio; Santos, Clementina M.M.; Balanay, Mannix P.; Cavaleiro, José; Silva, ArturKGaA, Weinheim The 1,6-conjugate addition of nitromethane to 2-[(1E,3E)-4-arylbuta-1,3-dien-1-yl]-4H-chromen-4-ones was accomplished and led mainly to the corresponding β-(nitromethyl)chromones. (E)-5′-(Nitromethyl)-3′-styryl-[1,1′-biphenyl] -2-ol and 3′-aryl-2′-nitro-5′-(nitromethyl)spiro[chromane-2,1′-cyclohexan]-4-one derivatives were also isolated as minor products from tandem processes, which result from the addition of a second molecule of nitromethane. The nucleophile scope was investigated with malononitrile, acetylacetone, ethyl cyanoacetate, and diethyl malonate, which gave the expected 1,6-addition products; in the last case, it was also possible to isolate a minor product formed through a 1,8-/1,6-addition sequence. Computational calculations provided a rationale for the experimental reactivity of carbon nucleophiles with 2-[(1E,3E)-4-arylbuta-1,3-dien-1-yl] -4H-chromen-4-ones. The further functionalization of some adducts allowed the preparation of new nitrogen-containing heterocyclic compounds, such as new styrylpyrrolidines and new pyrazole and bis(pyrazole) derivatives.
- 1-Aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas as VEGFR-2 tyrosine kinase inhibitors: Synthesis, biological evaluation, and molecular modelling studiesPublication . Soares, Pedro; Costa, Raquel; Froufe, Hugo J.C.; Calhelha, Ricardo C.; Peixoto, Daniela; Abreu, Rui M.V.; Ferreira, Isabel C.F.R.; Soares, Raquel; Queiroz, Maria João R.P.The Vascular Endothelial Growth Factor Receptor-2 (VEGFR-2) is a tyrosine kinase receptor involved in the growth and differentiation of endothelial cells that is implicated in tumor-associated angiogenesis. In this study novel 1-aryl-3-[4-(thieno[3,2-d]pyrimidin-4-yloxy)phenyl]ureas were synthesized and evaluated for the VEGFR-2 tyrosine kinase inhibition. Three of these compounds showed good VEGFR-2 inhibition presenting low IC50 values (150-199 nM) in enzymatic assays. The latter promoted also significant inhibition of cell proliferation at low concentrations (0.5-1 µM), not affecting cell viability, of VEGF-stimulated Human Umbilical Vein Endothelial Cells (HUVECs) using the BrdU assay. The determination of the total and phosphorylated (active) VEGFR-2 was performed by western-blot, and it was possible to conclude that the compounds significantly inhibit the phosphorylation of the receptor at 1 µM pointing to their antiproliferative mechanism of action in HUVECs. The molecular rationale for inhibiting the tyrosine kinase domain of VEGFR-2 was also done and discussed using molecular docking studies.
- 10 years of hyponatremia: focus on medical communication in liaison psychiatry. A case reportPublication . Pinho, Catarina; Maldonado, Emanuela; Correia, Joana; Guimarães, Manuel; Novo, André; Gomes, Joana Raposo; Cardoso, ConceiçãoEffective communication is one of the pillars of the doctor-patient relationship. Hyponatremia is defined as a decrease in serum sodium levels below 135 mEq/L. Objective To draw attention to the possible results of ineffective medical communication and the importance of active listening to the patient. Material and methods Descriptive study of the Case Report type, based on the Case REport guidelines. Case description: 85-year-old female, hospitalized from October to December 2021 in Acute Psychiatry for self-injurious behavior following an experiential crisis. In this episode, hyponatremia with 10 years of evolution was detected. She was evaluated by multiple medical specialties and in the last 10 years suffered from anorexia, asthenia, insomnia and dizziness, a condition attributed to psychoactive drug-related hyponatremia. After hospitalization in psychiatry, it was found that this condition started before the introduction of psychotropic drugs and that there could be a total restriction of salt in the diet, motivated by a bias in doctor-patient communication. Conclusion With a careful collection of the patient's history, it is possible to deconstruct and clarify concepts and beliefs that can negatively affect her health status.
- 100m and 200m front crawl performance prediction based on anthropometric and physiological measurementsPublication . Reis, Victor M.; Silva, A.J.; Carneiro, André Luiz; Marinho, D.A.; Novaes, Giovanni Silva; Barbosa, Tiago M.The identification of the variables that are able to predict swimming performance is one of the main purposes of the “swimming science” community. Research question: The aims of the study were: (i) to compare the anthropometric and physiological profiles of 100m and 200m front crawl swimmers and; (ii) to identify anthropometric and physiological variables that account for the prediction of the swimming performance at the 100m and 200m front crawl events. Methods: Twenty-six male swimmers were divided in two groups (12 for 100m group and 14 to 200m group). The swimmers’ personal best performance for the 100m and the 200m front crawl was converted to FINA points. The subjects performed a graded swimming test and an all-out test (100 or 200m maximal swims) in different days, in which physiological measures were evaluated. Forward step-by-step linear regression models were computed to predict swimming performance. The subjects’ performances (season best and all-out test) were taken as dependent variables. The age, physiological and anthropometric measures were selected as independent variables. Results: Anthropometric and physiological profiles of 100 and 200m swimmers are different and the mean oxygen uptake during exercise combined with training experience may explain 200m front crawl best season performance with a high precision (≈2% error). The models computed were able to predict from 44 % (i.e. 200m all-out bout) to 61 % (i.e. 200m season best) swimming performance. Predictive power of the models was less accurate in the 100m event (error > 10%). Conclusions: The authors conclude that the extent to which the physiological and anthropometric variables combine to predict performance probable is group-specific.
- 13th FINA World Championship finals: stroke kinematical and race times according to performance, gender and eventPublication . Jesus, Sérgio; Costa, M.J.; Marinho, D.A.; Garrido, Nuno D.; Silva, A.J.; Barbosa, Tiago M.The aim of this work was to compare the stroke kinematics and race times of the freestyle final races at the 13th FINA World Championships between: (i) the three medalists versus the last three finalists; (ii) males versus female swimmers; (iii) all events in each gender. Data was collected from the champioships official web site. There were no significant differences in the stroke kinematics neither in the race times between medallists and non-medallists. There were significant effects in the stroke kinematics and race times according to race event. There were significant effects in the stroke kinematics and race times according to swimmers gender. It seems there are different tactics and biomechanical strategies according to gender and swimming event.
- 17 α-Ethinylestradiol degradation in continuous process by photocatalysis using Ag/Nb2O5 immobilized in biopolymer as catalystPublication . Lenzi, Giane G.; Abreu, Eduardo; Fuziki, Maria Eduarda K.; Fidelis, Michel Zampieri; Brackmann, Rodrigo; Díaz de Tuesta, Jose Luis; Gomes, Helder; Santos, Onélia A.A. dosThis study describes the application of Ag/Nb2O5 catalysts, suspension and spheres alginate immobilized for the degradation of 17α-Ethinylestradiol (EE2). The techniques used to characterize the photocatalysts were as follows: X-ray diffraction (XRD), N2 adsorption–desorption analysis (BET), point charge zero charge (PZC), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Different catalyst calcination temperatures were studied by keeping the silver metal loading at 5%. Among the operational conditions analyzed were pH, catalyst concentration, the emitting source of radiation and the inlet flow rate (in continuous operation). The results of the experiments performed initially with the catalyst in suspension revealed that the highest catalytic activity in the degradation of EE2 was the 5%Ag/Nb2O5 catalyst calcined at 973 K, which removed 77.7% of the initial pollutant concentration in 120 min of reaction. The immobilization of the catalyst in alginate spheres resulted in a degradation reduction, being able to degrade 69.2% of the initial EE2 in a batch system. In the continuous system, the immobilized catalyst obtained a total degraded of 37.3%, with a flow rate of 10 L·h−1. Catalyst reuse was promising, even dropping the removal, degrading around 27% of the initial EE2 concentration in the third cycle of use.
- 18 anos depois: os anuários financeiros dos municípios portugueses e o seu contributo para a (r)evolução das finanças locaisPublication . Costa, Cláudia S.; Maia, TâniaDecorridas quase duas décadas desde a primeira publicação do Anuário Financeiro dos Municípios Portugueses, este é hoje um indubitável mecanismo de análise, escrutínio, partilha, aprendizagem, investigação e participação democrática na realidade do universo autárquico (leia-se municípios, serviços municipalizados e empresas municipais). Envolvendo a colaboração ativa de dois centros de investigação, de filiação dos autores - o Centro de Investigação em Contabilidade e Fiscalidade, do Instituto Politécnico do Cávado e do Ave, e o Centro de Investigação em Ciência Política, da Universidade do Minho -, esta obra empreende o trabalho hercúleo de análise das contas individuais do universo municipal, dos serviços municipalizados e das empresas municipais e constitui uma referência para a transparência da informação financeira pública local. Conta igualmente com a partilha do Tribunal de Contas e do cumprimento do dever de informação dos municípios, no que toca à disponibilização dos documentos de prestação de contas. Assim, o presente artigo tem como objetivo analisar a evolução da estrutura e conteúdo dos Anuários Financeiros dos Municípios Portugueses ao longo dos seus 18 anos de edição, explorando os seus contributos para a (r)evolução das finanças locais, sem pretensão de tecer qualquer comentário ou avaliação de ordem técnica. Este segue a estrutura daquilo que as autoras consideram ser as diferentes fases do Anuário Financeiro: i) fase de transição (exercícios económicos entre 2003-2008), com o objetivo de analisar a conformidade com os requisitos legais e o sistema contabilístico vigente, evidenciando o elencar dos primeiros objetivos dos Anuários Financeiros dos Municípios Portugueses; ii) fase de estabilização (exercícios económicos 2009-2019) de práticas e formalidades inerentes à contabilidade pública autárquica, estabilizando os objetivos de discussão, avaliação e divulgação da situação financeira, patrimonial e orçamental individual e agregada do universo municipal e do setor empresarial local, bem como o ranqueamento dos municípios, em função do comportamento observado em indicadores de natureza financeira e orçamental; e iii) fase de transição para o novo normativo contabilístico SNC-AP (2020-2022) e os decorrentes desafios de implementação e comparabilidade. O artigo termina com algumas considerações finais e desafios prospetivos à elaboração dos Anuários Financeiros.
- 1D and 2D modeling and simulation of radial combustion propagation on Fe 2O 3/Al thermite systemsPublication . Brito, Paulo; Durães, Luísa; Portugal, AntónioIn previous works, a one-dimensional model was built to simulate the nonsteady radial combustion propagation on thin disk-shaped samples of Fe2O3/aluminum thermite mixtures and was successfully tested. Now, the purpose is to extend the referred model to the more sensible two-dimensional features of the samples, maintaining the main characteristics of the previous model: zero-order kinetics, conductive/radiative heat transfer, assumption of phase transitions, temperature and composition dependency for all system properties during propagation. Therefore, an adaptive numerical algorithm that conjugates a method of lines (MOL) strategy based on finite differences space discretizations, with a collocation scheme based on increasing level dyadic grids is applied for the solution of the problem. The particular integration method proves to cope satisfactorily with the steep traveling thermal wave in 1D and 2D spatial domains, either for trivial uniform mixing conditions, as in complex examples developed to feature more sophisticated circumstances, such as nonhomogeneous reactant mixing, which realistically replicate the observed experimental conditions.
- 2,3-Diarylxanthones as potential inhibitors of Arachidonic acid metabolic pathwaysPublication . Santos, Clementina M.M.; Ribeiro, Daniela; Silva, Artur; Fernandes, EduardaIn response to an inflammatory stimulus, arachidonic acid (AA), the main polyunsaturated fatty acid present in the phospholipid layer of cell membranes, is released and metabolized to a series of eicosanoids. These bioactive lipid mediators of inflammation arise physiologically through the action of the enzymes 5-lipoxygenase (5-LOX) and cyclooxygenases (constitutive COX-1 and inducible COX-2). It is believed that dual inhibition of 5-LOX and COXs may have a higher beneficial impact in the treatment of inflammatory disorders rather than the inhibition of each enzyme. With this demand for new dual-acting anti-inflammatory agents, a range of 2,3-diarylxanthones were tested through their ability to interact in the AA metabolism. In vitro anti-inflammatory activity was evaluated through the inhibition of 5-LOX-catalyzed leukotriene B4 (LTB4) formation in human neutrophils and inhibition of COX-1- and COX-2-catalyzed prostaglandin E2 (PGE2) formation in human whole blood. The results showed that some of the studied arylxanthones were able to prevent LTB4 production in human neutrophils, in a concentration-dependent manner. The xanthone with a 2-catechol was the most active one (IC50 ∼ 9 μM). The more effective arylxanthones in preventing COX-1-catalyzed PGE2 production presented IC50 values from 1 to 7 μM, exhibiting a structural feature with at least one non-substituted aryl group. All the studied arylxanthones were ineffective to prevent the formation of PGE2 catalyzed by COX-2, up to the maximum concentration of 100 μM. The ability of the tested 2,3-diarylxanthones to interact with both 5-LOX and COX-1 pathways constitutes an important step in the research of novel dual-acting anti-inflammatory drugs.
- 2,3-Diarylxanthones as strong scavengers of reactive oxygen and nitrogen species: a structure–activity relationship studyPublication . Santos, Clementina M.M.; Freitas, Marisa; Ribeiro, Daniela; Gomes, Ana Sara; Silva, Artur; Cavaleiro, José; Fernandes, EduardaXanthones are a class of oxygen-containing heterocyclic compounds widely distributed in nature. The natural derivatives can present different substitutions in the xanthone core that include hydroxyl, methoxyl, prenyl and glycosyl groups. The inclusion of aryl groups has only been reported for a few synthetic derivatives, the 2,3-diaryl moiety being recently introduced by our group. Xanthones are endowed with a broad spectrum of biological activities, many of them related to their antioxidant ability, including the scavenging of reactive oxygen species (ROS) and reactive nitrogen species (RNS), as well as metal chelating effects. Considering the interesting and promising antioxidant activities present in compounds derived from the xanthone core, the main goal of this work was to evaluate the scavenging activity of the new 2,3-diarylxanthones for ROS, including superoxide radical (O2 ), hydrogen peroxide (H2O2), singlet oxygen (1O2), peroxyl radical (ROO ) and hypochlorous acid (HOCl), and RNS, including nitric oxide ( NO) and peroxynitrite anion (ONOO ). The obtained results revealed that the tested 2,3-diarylxanthones are endowed with outstanding ROS and RNS scavenging properties, considering the nanomolar to micromolar range of the IC50 values found. The xanthones with two catechol rings were the most potent scavengers of all tested ROS and RNS. In conclusion, the new 2,3-diarylxanthones are promising molecules to be used for their potential antioxidant properties.