Comportamento do tronco na fase inicial da sequência de movimento de sentado para de pé, em indivíduos com Acidente Vascular Encefálico, em fase aguda

As alterações do controlo postural do tronco observadas em indivíduos pós acidente vascular encefálico (AVE) podem traduzir-se em dificuldades na realização da sequência de movimento de sentado para de pé (STS). Desta forma, o presente estudo teve como objetivo descrever o comportamento do tronco, durante a primeira fase do STS, em cinco indivíduos pós-AVE, em fase aguda. Para tal, os indivíduos foram avaliados em dois momentos, antes (M0) e após (M1) um período de intervenção de 3 meses. Recorreu-se ao Software de Avaliação Postural (SAPo) para analisar o deslocamento do tronco no sentido anterior, bem como a simetria entre hemitronco contralesional vs. ipsilesional. Avaliou-se também o controlo postural e equilíbrio através das Escala de Avaliação Postural para Pacientes com Sequelas de AVE (PASS) e Escala de Equilíbrio de Berg (EEB), respetivamente. Para cada indivíduo foi desenvolvido um processo de raciocínio clínico tendo por base a avaliação observacional de componentes do movimento. Os resultados evidenciaram uma diminuição do deslocamento do tronco entre M0 e M1, em três dos cinco indivíduos, no que se refere ao ângulo do plano horizontal - EIPS - ângulo inferior da omoplata e do plano horizontal – EIPS – acrómio; outro dos indivíduos, no M0 não foi capaz de realizar o deslocamento do tronco, mas concluiu-o em M1; e outro indivíduo aumentou esse deslocamento nos dois ângulos. Em relação à diferença das distâncias entre o hemitronco contralesional vs ipsilesional, para o ângulo superior da omoplata e C7, estes resultados diminuíram de M0 para M1 em todos os indivíduos. Em quatro dos cinco indivíduos, as diferenças das distâncias para o ângulo inferior da omoplata e T7 e o ângulo inferior da omoplata e a EIPS, entre o hemitronco contralesional vs ipsilesional também diminuíram no M1 comparativamente ao M0. Foi ainda possível observar que todos os indivíduos apresentaram uma melhor extensão linear do tronco na posição inicial de sentado em M1 comparativamente a M0. Para as escalas aplicadas, PASS e EEB, a maioria dos indivíduos em estudo duplicou em M1 a pontuação obtida em M0. Concluindo, os participantes do estudo evidenciaram um menor deslocamento anterior do tronco durante o STS, assim como, uma maior simetria entre os dois hemitroncos, após uma intervenção de fisioterapia baseada nos princípios do conceito de Bobath.Changes in postural control of the trunk observed in individuals post stroke can translate into difficulties in the realization of the sequence of movement from sitting to standing (STS). Thus, this study aimed to describe the behavior of the trunk during movement on the stage one: flexion momentum of the STS, in five individuals with stroke in the acute phase. To this end, subjects were evaluated at two times before (M0) and after (M1) a period of three months of intervention. Resorted to the Postural Assessment Software (SAPo) to analyze the displacement of the trunk in forward as well as the symmetry between contralesional vs. ipsilesional hemitrunks. We also evaluated the postural control and balance through the Postural Assessment Scale for Stroke Patients (PASS) and Berg Balance Scale (BBS), respectively. For each individual, we developed a clinical reasoning process based on the assessment of observational components of the movement. The results showed a decrease in the displacement of the trunk between M0 and M1 in three of the five individuals with regard to the angle from the horizontal plane - EIPS - inferior angle of the scapula and the horizontal plane - EIPS - acromion; other individuals in M0 was not able to perform the displacement of the trunk, but found it to M1, and another individual increased that the two displacement angles. Regarding the difference of the distances between the contralesional vs. ipsilesional hemitrunks to the superior angle of the scapula and C7 these results M0 to M1 decreased in all subjects. In four of the five subjects, the differences of the distances to the inferior angle of the scapula and T7 and the inferior angle of the scapula and the EIPS, between contralesional vs. ipsilesional hemitrunks, in M1 also decreased in comparison to M0. It was also observed that all subjects had a best linear extension of the trunk in the initial position of sitting in M1 compared to M0. For scales applied, PASS and BBS, the majority of individuals in the study doubled the score in M1 M0. In conclusion, the study participants showed a smaller anterior displacement of the trunk during the STS, as well as greater symmetry between the two hemitrunks after a physical therapy intervention based on the principles of the Bobath concept

Fracture Characterisation of bonded joints between cortical bone tissue and bone cement

The process of evolution has led to the creation of fantastic materials. Bone is one of these materials and has a complex, anisotropic, hierarchical and heterogeneous microstructure, characterised by an excellent mechanical performance. However, as it is an almost fragile material, it often ends up fracturing. These fractures decrease the patient's quality of life and entail high costs for the health system. In order to deal with these fractures, the BoFraPla project arose, which aims to develop a fibrous system for fixing bone fractures. Therefore, in the scope of the activities of this project, the present dissertation emerges, proposing to mechanically characterise the bond between the bone and bone cement. From a thorough literature review, it was found that although the bone cement has been used for more than fifty years, there are few references to its mechanical characterisation and none were found that have made a clear characterisation of the fracture process between the bone and the cement. Hence, in this report, a pure mode I characterisation (tension) through a Double Cantilever Beam (DCB) test and another pure mode II characterisation (shear) through an End-Notched Flexure (ENF) test are presented. In order to overcome the difficulties in monitoring the crack length during the laboratory tests, a method based on the equivalent crack length was used. With this method, the resistance curve was drawn for each specimen and, in most of them, the existence of thresholds was remarkable, which allowed a correct measurement of the fracture energy for each test. In order to validate the results obtained, numerical simulations were performed with cohesive models. Through the results, it was possible to determine that the chosen tests, the defined dimensions and the adopted procedure, can be used to characterise the fracture of these two materials in the studied loading modes.O processo de evolução natural levou à existência de materiais fantásticos. O osso é um destes materiais e apresenta uma microestrutura complexa, anisotrópica, hierárquica e heterogénea, caracterizada por um excelente desempenho mecânico. Contudo, como se trata de um material quase frágil, inúmeras vezes acaba por fraturar. Estas fraturas diminuem a qualidade de vida do paciente e acarretam elevados custos para o sistema de saúde. Com vista ao tratamento destas fraturas, surgiu o projeto BoFraPla, que se propõe a desenvolver um sistema fibroso de fixação de fraturas ósseas. Assim, no âmbito das atividades deste projeto, surge a presente dissertação que se propõe a caracterizar mecanicamente a ligação entre o osso e um cimento ósseo. A partir de uma profunda revisão bibliográfica apurou-se que, apesar do cimento ósseo ser utilizado há mais de cinquenta anos, existem poucas referências à sua caracterização mecânica, não sendo encontrada nenhuma que fizesse uma clara caracterização do processo de fratura entre o osso e o cimento. Assim, neste relatório é apresentada uma caracterização em puro modo I (tensão), através de um ensaio Double Cantilever Beam (DCB) e outra caracterização em puro modo II (cisalhamento), através de um ensaio End-Notched Flexure (ENF). Para colmatar as dificuldades de monitorização do comprimento de fenda durante os ensaios laboratoriais, recorreu-se a um método baseado no comprimento de fenda equivalente. Com este método foi traçada a curva de resistência para cada provete, sendo notória a existência de patamares na sua maioria, o que permite uma correta medição da energia de fratura para cada ensaio. Com vista a validar os resultados obtidos, foram realizadas simulações numéricas com modelos coesivos. Através dos resultados, foi possível apurar que os ensaios escolhidos, as dimensões definidas e o procedimento adotado, podem ser utilizados para caracterizar à fratura entre estes dois materiais nos modos de carregamento estudados

Tauroursodeoxycholic Acid Drives Mitochondrial Bioenergetics Toward Neural Stem Cell Proliferation

Neurogenesis occurs throughout life in discrete areas of the adult mammalian brain. Unfortunately, there is a lack of effective regeneration during aging or after injury. Therefore, life-long potentiation of endogenous neurogenesis represents a major issue. Curiously, proliferation and differentiation potential of neural stem cells (NSCs) were recently shown to be highly dependent on mitochondrial bioenergetics and fatty acid (FA) lipogenesis. Furthermore, tauroursodeoxycholic acid (TUDCA), an endogenous neuroprotective bile acid, considered a regulator of energy metabolism and an inhibitor of early differentiation-associated apoptosis events in NSCs, stimulates proliferation and neuronal conversion of these cells. We aimed to clarify the impact of TUDCA on the mitochondrial proteome in self-renewing or differentiating mouse NSCs, using liquid chromatography coupled with mass spectrometry (LC-MS) based detection of differential proteomics. Validation of mitochondrial proteomic analysis by Western blot in two different NSC lines revealed that TUDCA significantly decreases the mitochondrial levels of long-chain acyl-CoA dehydrogenase (LCAD) protein upon differentiation, an enzyme crucial for β-oxidation of long-chain FAs. Further, nuclear levels of sterol regulatory element-binding protein (SREBP-1), a major transcription factor of lipid biosynthesis, were also found significantly increased, as the levels of palmitic and stearic FAs raise up. Interestingly, mitochondrial levels of pyruvate dehydrogenase E1-α (PDHE1-α), an enzymatic subunit belonging to glucose metabolism, were also markedly enhanced by TUDCA. Of note, TUDCA promoted mitochondria-nucleus translocation of PDHE1-α. Therefore, the proliferative role of this bile acid may rely, in part, in increasing the pool of mitochondrial and/or nuclear acetyl-CoA to assure NSC cycle progression. Finally, LCAD, SREBP-1, and PDHE1-α expression profiles were also assessed during early stages of neural differentiation bringing novel insights to NSC metabolic choices throughout differentiation. Altogether, our results unravel the metabolic impact of TUDCA in controlling NSC fate, demonstrating that this bile acid not only induces mitochondrial advantageous conditions but also metabolic plasticity

The pine wood nematode, Bursaphelenchus xylophilus, in Portugal: possible introductions and spread routes of a serious biological invasion revealed by molecular methods

The pine wood nematode (PWN), Bursaphelenchus xylophilus, the causal agent of pine wilt disease (PWD), is a major world-wide pathogen and pest of pine, with impacts on forest health, natural ecosystem stability and international trade. In Portugal, PWN was first diagnosed in 1999, the first occurrence also for Europe. The disease was recently detected on the island ofMadeira and in northern Spain. In an attempt to search for more reliable and robust molecular markers that enable the study of intraspecific variability of B. xylophilus from different geographic locations, the intergenic spacer (IGS) region of the 5S rRNA gene and inter-simple sequence repeats (ISSR) analysis were used to determine the genetic relationships among 43 B. xylophilus isolates from Portugal, China, Japan, South Korea and USA. IGS sequence analysis showed that this region can only be used to establish interspecific relationships, since no differences were detected among Portuguese isolates from different geographic locations. Fingerprints obtained with ISSR show high genetic variability among Portuguese isolates, except for the ones obtained prior to 2008. The ISSR dendrogram suggests the spread of the disease inside continental Portugal and to Madeira. Until 2008, B. xylophilus populations found in continental Portugal showed low genetic diversity, pointing to a single introduction, probably from Asia, whereas recent populations from continental Portugal (2009-2010) and Madeira show high genetic diversity, suggesting multiple introductions from different origins

Rethinking the stylistic categories of Portuguese 19th Century Sculpture: The Work of António Teixeira Lopes

El artículo reflexiona sobre las categorías estilísticas de la escultura portuguesa del siglo XIX a partir del análisis de la obra de António Teixeira Lopes, considerado el principal representante del naturalismo escultórico de este país. En primer lugar, se aborda el concepto de naturalismo en la historia del arte portuguesa, ofreciendo una visión crítica sobre su separación en relación con el Romanticismo, a diferencia de la teoría dominante en la historiografía especializada sobre este tema. Al mismo tiempo, demostraremos la dificultad que entraña la aplicación de los conceptos de análisis de la pintura a la escultura cuando se analiza una obra de arte concreta. En segundo lugar, con el contexto artístico portugués como telón de fondo, se estudia la carrera académica y profesional de Teixeira Lopes. Finalmente, a partir del análisis de la obra del escultor y del conocimiento de sus métodos y puntos de vista sobre el arte, se cuestiona el etiquetado de Lopes como naturalista y se defiende la necesidad de una comprensión menos compartimentada del arte del siglo XIX

Dissecting cross-talk between microglia and motoneurons in ALS: signaling events and soluble factors

Dissertação para obtenção do Grau de Mestre em Genética Molecular e BiomedicinaConvergence of pathways in motoneuron (MN) injury include microglia in the initiation and progression of Amyotrophic Lateral Sclerosis (ALS). Neuroinflammation is a pathological hallmark of ALS and microglia may acquire neurotoxic or neuroprotective properties in response to misfolded superoxide dismutase-1 (SOD1) or other molecules produced by the injured MN. We assessed: (i) the role of microglia in preventing/restoring MN dysfunction using a mixed culture of NSC-34 MN-like cells (mutated in G93A) and of N9 microglia cells, added at 0 or 2 days-invitro(M0, M2) and cultured till 4 and 7 days-in-vitro; (ii) neurodegenerative network in organotypic cultures from lumbar segments of spinal cord (SC) obtained from the ALS mice model TgSOD1-G93A at 7 day-old and aged for 10 days-in-vitro, as well as the response to lipopolysaccharide (LPS, 1μg/mL) immunostimulation. Western blot assays for SOD1, high-mobility-group-box-protein-1 (HMGB1) and toll-like receptor-4 (TLR-4), and fluorimetric/colorimetric assays for ATP, glutamate and nitric oxide (NO), were used. Microglia (M0/M2) decreased the accumulation of human/mouse mutated SOD1 (P<0.01). In addition, elevation of glutamate efflux (P<0.01), and reduction of extracellular ATP (P<0.01), MMP-2(P<0.05) and MMP-9 (P<0.01) was observed by M2 at 7 days-in-vitro. Reduction of NO (P<0.05) and MMP-2 (P<0.01) was obtained with M0. HMGB1 increased by M0 and decreased by M2, suggesting HMGB1 release from the cell. Accumulation of SOD1 was verified in SC organotypic cultures, but no changes in ATP or NO were obtained, although a slight decrease in ATP by LPS was verified. Downregulation of TLR-4 by LPS may indicate the exhaustion of the inflammatory response mechanisms in the aged SC culture. Together, these results suggest that microglia by inhibiting MMP activation and HMGB1 cytoplasmic translocation in the ALS model are key in modulating MN degeneration and should be considered as therapeutic targets in ALS.supported by FEDER (COMPETE Programme) and by National funds (Fundação para a Ciência e a Tecnologia – FCT, Portugal) with the projects PTDC/SAU-FAR/118787/2010 to D.B. and PEst-OE/SAU/UI4013/2011 and 2012 to iMed.U

Paralytic shellfish toxins and ocean warming: bioaccumulation and ecotoxicological responses in jujvenile Gilthead Seabream (Sparus aurata)

Warmer seawater temperatures are expected to increase harmful algal blooms (HABs) occurrence, intensity, and distribution. Yet, the potential interactions between abiotic stressors and HABs are still poorly understood from ecological and seafood safety perspectives. The present study aimed to investigate, for the first time, the bioaccumulation/depuration mechanisms and ecotoxicological responses of juvenile gilthead seabream (Sparus aurata) exposed to paralytic shellfish toxins (PST) under different temperatures (18, 21, 24 °C). PST were detected in fish at the peak of the exposure period (day five, 0.22 µg g-1 N-sulfocarbamoylGonyautoxin-1-2 (C1 and C2), 0.08 µg g-1 Decarbamoylsaxitoxin (dcSTX) and 0.18 µg g-1 Gonyautoxin-5 (B1)), being rapidly eliminated (within the first 24 h of depuration), regardless of exposure temperature. Increased temperatures led to significantly higher PST contamination (275 µg STX eq. kg-1). During the trial, fish antioxidant enzyme activities (superoxide dismutase, SOD; catalase, CAT; glutathione S-transferase, GST) in both muscle and viscera were affected by temperature, whereas a significant induction of heat shock proteins (HSP70), Ubiquitin (Ub) activity (viscera), and lipid peroxidation (LPO; muscle) was observed under the combination of warming and PST exposure. The differential bioaccumulation and biomarker responses observed highlight the need to further understand the interactive effects between PST and abiotic stressors, to better estimate climate change impacts on HABs events, and to develop mitigation strategies to overcome the potential risks associated with seafood consumption.Agência financiadora European Union (EU) 678193 Portuguese Foundation for Science and Technology (FCT) IF/00253/2014 CEECIND/01739/2017 UID/Multi/04326/2019info:eu-repo/semantics/publishedVersio

The influence of chain orientation in the electric behaviour of polymer diodes

Recently some experimental results have showed that the spatial alignment of conjugated polymer chains on nanometre length scales can influence the behaviour of polymer-based electronic devices, such as light-emitting diodes, field effect transistors, and photovoltaic cells. The effects of chain orientation at electrode-polymer interfaces on the charge injection process and charge mobility through the polymer layer are not well understood. In this work we use a generalized dynamical Monte Carlo method to study the influence of different polymer chain orientation relative to the electrodes surface on the electric behaviour of single-layer polymer diode, namely density current and charge density.Fundação para a Ciência e a Tecnologia (FCT) - POCTI/CTM/41574/2001; CONC-REEQ/443/EEI/2005; SFRH/BD/22143/2005FEDE

Computer simulation of hole distribution in polymeric materials

Polymers have been known for their flexibility and easy processing into coatings and films, which made them suitable to be applied in a variety of areas and in particular the growing area of organic electronics. The electronic properties of semiconducting polymers made them a serious rival in areas where until now inorganic materials were the most used, such as light emitting diodes or solar cells. Typical polymers can be seen as a network of molecular strands of varied lengths and orientations, with a random distribution of physical and chemical defects which makes them an anisotropic material. To further increase their performance, a better understanding of all aspects related to charge transport and space charge distribution in polymeric materials is required. The process associated with charge transport depends on the properties of the polymer molecules as well as connectivity and texture, and so we adopt a mesoscopic approach to build polymer structures. Changing the potential barrier for charge injection we can introduce holes in the polymer network and, by using a generalised Monte-Carlo method, we can simulate the transport of the injected charge through the polymer layer caused by imposing a voltage between two planar electrodes. Our results show that the way that holes distribute within polymer layer and charge localization in these materials is quite different from the inorganic ones.Fundação para a Ciência e a Tecnologia (FCT) – Programa Operacional “Ciência, Tecnologia, Inovação” – POCTI/CTM/41574/2001, CONC-REEQ/443/EEI/2005, SFRH/BD/22143/2005European Community Fund (FEDER