RCAAP Repository

Epithelial wound healing relies on tissue movements and cell shape changes. Our work shows that, immediately after wounding, there was a dramatic cytoskeleton remodeling consisting of a pulse of actomyosin filaments that assembled in cells around the wound edge and flowed from cell to cell toward the margin of the wound. We show that this actomyosin flow was regulated by Diaphanous and ROCK and that it elicited a wave of apical cell constriction that culminated in the formation of the leading edge actomyosin cable, a structure that is essential for wound closure. Calcium signaling played an important role in this process, as its intracellular concentration increased dramatically immediately after wounding, and down-regulation of transient receptor potential channel M, a stress-activated calcium channel, also impaired the actomyosin flow. Lowering the activity of Gelsolin, a known calcium-activated actin filament-severing protein, also impaired the wound response, indicating that cleaving the existing actin filament network is an important part of the cytoskeleton remodeling process.

Residence within a customized vacuole is a highly successful strategy used by diverse intracellular microorganisms. The parasitophorous vacuole membrane (PVM) is the critical interface between Plasmodium parasites and their possibly hostile, yet ultimately sustaining, host cell environment. We show that torins, developed as ATP-competitive mammalian target of rapamycin (mTOR) kinase inhibitors, are fast-acting antiplasmodial compounds that unexpectedly target the parasite directly, blocking the dynamic trafficking of the Plasmodium proteins exported protein 1 (EXP1) and upregulated in sporozoites 4 (UIS4) to the liver stage PVM and leading to efficient parasite elimination by the hepatocyte. Torin2 has single-digit, or lower, nanomolar potency in both liver and blood stages of infection in vitro and is likewise effective against both stages in vivo, with a single oral dose sufficient to clear liver stage infection. Parasite elimination and perturbed trafficking of liver stage PVM-resident proteins are both specific aspects of torin-mediated Plasmodium liver stage inhibition, indicating that torins have a distinct mode of action compared with currently used antimalarials.

Behçet's disease (BD) is a complex disease with genetic and environmental risk factors implicated in its etiology; however, its pathophysiology is poorly understood. To decipher BD's genetic underpinnings, we combined gene expression profiling with pathway analysis and association studies. We compared the gene expression profiles in peripheral blood mononuclear cells (PBMCs) of 15 patients and 14 matched controls using Affymetrix microarrays and found that the neuregulin signaling pathway was over-represented among the differentially expressed genes. The Epiregulin (EREG), Amphiregulin (AREG), and Neuregulin-1 (NRG1) genes of this pathway stand out as they are also among the top differentially expressed genes. Twelve haplotype tagging SNPs at the EREG-AREG locus and 15 SNPs in NRG1 found associated in at least one published BD genome-wide association study were tested for association with BD in a dataset of 976 Iranian patients and 839 controls. We found a novel association with BD for the rs6845297 SNP located downstream of EREG, and replicated three associations at NRG1 (rs4489285, rs383632, and rs1462891). Multifactor dimensionality reduction analysis indicated the existence of epistatic interactions between EREG and NRG1 variants. EREG-AREG and NRG1, which are members of the epidermal growth factor (EGF) family, seem to modulate BD susceptibility through main effects and gene-gene interactions. These association findings support a role for the EGF/ErbB signaling pathway in BD pathogenesis that warrants further investigation and highlight the importance of combining genetic and genomic approaches to dissect the genetic architecture of complex diseases.

Methods: Forty-five patients (40 women, 5 men; mean age 45.6 yrs) with untreated recent-onset polyarthritis participated in this prospective study and were examined using an US and MRI approach including both wrists and hands. After a followup of 12 months, patients were classified as having RA if they fulfilled the criteria for RA. The proportion of synovitis identified by US and MRI for each joint and tendon region was compared by chi-square test. The diagnostic performance of US and MRI for RA identification was evaluated using receiver-operating curve (ROC) analysis. Possible associations between synovitis for each joint and tendon region as identified by US or MRI and RA diagnosis at 12 months were tested by logistic regression analysis. The diagnostic performance of the ACR/EULAR RA classification criteria corrected by US and MRI joint and tendon counts was evaluated using ROC analysis. Results: Thirty patients fulfilled the ACR/EULAR criteria [early RA (ERA) patients] and the remaining 15 failed to meet these criteria (non-RA). Carpal joint synovitis and tenosynovitis of the flexor tendons was found in 86.7% and 86.7% of patients with ERA on MRI compared with 63.3% and 50% on US, respectively (p < 0.05). The global MRI and US counts revealed a good diagnostic performance for RA diagnosis of both techniques, although MRI was statistically significantly better [area under the curve (AUC) = 0.959 and AUC = 0.853, respectively; z statistic = 2.210, p < 0.05]. MRI identification of carpal joint synovitis (OR 3.64, 95% CI 1.119-11.841), tenosynovitis of the flexor tendons (OR 5.09, 95% CI 1.620-16.051), and global joint and tendon count (OR 2.77, 95% CI 1.249-6.139) were in the multivariate logistic regression model the most powerful predictors of progression toward RA. In the group of ERA patients with US joint and tendon counts ≤ 10, a statistically significant difference was found between the diagnostic performance for RA of the ACR/EULAR criteria as previously described and the diagnostic performance of the MRI-corrected ACR/EULAR criteria (AUC = 0.898 and AUC = 0.986, respectively; z statistic = 2.181, p < 0.05). Conclusion: 3.0-T MRI identified a higher prevalence of synovitis in comparison to US in an early polyarthritis cohort. Both techniques have good diagnostic performance for RA although MRI reveals a significantly higher diagnostic capability. Synovitis of carpal joints and of flexor tendons as identified by MRI were the most powerful predictors of progression toward RA. In patients with US joint and tendon counts ≤ 10, MRI can significantly improve the diagnostic performance of the 2010 ACR/EULAR classification criteria.

Objective: B cells play important roles in rheumatoid arthritis (RA). Given the beneficial effect of B cell depletion therapy in RA as well as the observed alterations in B cell subpopulations in this disease, we evaluated whether changes in the expression of genes related to B cell survival and activation were already present in patients with untreated very early RA (VERA; < 6 weeks of disease duration). Methods: The expression of a group of B cell-related activation and survival genes was quantified in peripheral blood mononuclear cells from patients with VERA by real-time PCR and compared with untreated early RA (< 1 year), established treated RA, and other untreated early arthritis conditions. Serum B cell-activating factor belonging to the tumor necrosis factor family (BAFF) was quantified by ELISA. Results: BAFF gene expression and serum levels were highest in patients with VERA. The expression of BAFF receptor (BAFF-R) increased with disease progression, while transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) was elevated since the first weeks of RA onset. Paired box 5 gene expression was also increased at all RA stages. Chemokine (C-X-C motif) receptor 5 was elevated only in established RA. No differences were observed in B cell maturation antigen, activation-induced cytidine deaminase, B lymphocyte-induced maturation protein, and B cell lymphoma 2 expression. Conclusion: Disturbances in the expression of B cell-related activation and survival genes, particularly BAFF and TACI, occur from the onset of RA and precede changes in BAFF-R. These alterations can lead to the development of autoreactive B cells from the first weeks of RA onset.

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Na obra de Agostinho da Silva, o humanismo e o universalismo são acentuados pela singularidade na arte de dizer e fazer educação. Neste apontamento, procurarei salientar estes aspectos e farei convergir o olhar para o depoimento que, em 1968, o filósofo proferiu na Câmara Parlamentar, em Brasília. Aí defendeu que a Universidade de Brasília fosse uma Escola Normal de Universidades, recebendo estudantes de todo o Brasil e formando-os para professores das outras universidades.

Many acute viral infections can be controlled by vaccination; however, vaccinating against persistent infections remains problematic. Herpesviruses are a classic example. Here, we discuss their immune control, particularly that of gamma-herpesviruses, relating the animal model provided by murid herpesvirus-4 (MuHV-4) to human infections. The following points emerge: (i) CD8(+) T-cell evasion by herpesviruses confers a prominent role in host defence on CD4(+) T cells. CD4(+) T cells inhibit MuHV-4 lytic gene expression via gamma-interferon (IFN-gamma). By reducing the lytic secretion of immune evasion proteins, they may also help CD8(+) T cells to control virus-driven lymphoproliferation in mixed lytic/latent lesions. Similarly, CD4(+) T cells specific for Epstein-Barr virus lytic antigens could improve the impact of adoptively transferred, latent antigen-specific CD8(+) T cells. (ii) In general, viral immune evasion necessitates multiple host effectors for optimal control. Thus, subunit vaccines, which tend to prime single effectors, have proved less successful than attenuated virus mutants, which prime multiple effectors. Latency-deficient mutants could make safe and effective gamma-herpesvirus vaccines. (iii) The antibody response to MuHV-4 infection helps to prevent disease but is suboptimal for neutralization. Vaccinating virus carriers with virion fusion complex components improves their neutralization titres. Reducing the infectivity of herpesvirus carriers in this way could be a useful adjunct to vaccinating naive individuals with attenuated mutants.

Background: Mig-SCog is a 9-item questionnaire developed to quantify attack-related cognitive complaints in migraine (M). The items relate to executive function and language, and the total Mig-SCog score is the sum of those scales. Objective: To evaluate the Mig-SCog scores regarding cognitive symptoms during a variety of conditions. Methods: We conducted a prospective comparative study of the Mig-SCog scores (1) between migraine and tension-type headache (TTH) patients during a headache; (2) in migraine patients between migraine attacks, non-headache pain and pain-free status; (3) in migraine patients during and outside a migraine attack. Results: One hundred forty-nine patients (98 M and 51 TTHA). Total Mig-SCog score was higher in migraine patients than TTH (8.0 ± 4.1 vs 3.4 ± 3.2, P < .0001). Sixty-three patients took part in the next part of the study. Migraine patients rated the Mig-SCog higher for migraine (7.9 ± 4.6) than for non-headache pain (2.3 ± 2.9, P < .0006) or pain-free (1.6 ± 2.4, P < .0006). In the final phase of the study, 38 patients Mig-SCog scores were not significantly different whether obtained during or outside an M attack (P = .26). Conclusions: Attack-related subjective cognitive symptoms, assessed by Mig-SCog scores, differed between migraine and TTH patients. The Mig-SCog scores from migraine patients were found to be higher during migraine than during non-headache pain or pain-free conditions. Patient scoring from memory for usual attacks was not significantly different to scoring within attacks, We believe this demonstrates negligible recall bias.

The first obligatory phase of mammalian infection by Plasmodium parasites, the causative agents of malaria, occurs in the liver of the host. This stage of Plasmodium infection bears enormous potential for anti-malarial intervention. Recent technological progress has strongly contributed to overcoming some of the long-standing difficulties in experimentally assessing hepatic infection by Plasmodium. Here, we review appropriate infection models and infection assessment tools, and provide a comprehensive description of recent advances in experimental strategies to investigate the liver stage of malaria. These issues are discussed in the context of current challenges in the field to provide researchers with the technical tools that enable effective experimental approaches to study liver stage malaria.

Introduction: Respiratory tests are fundamental for monitoring respiratory function in ALS, and essential in clinical trials. Slow vital capacity (SVC) was canceled in some countries to prevent COVID-19 transmission. We aimed to test phrenic nerve motor responses as an option to SVC in clinical trials. Methodology: Patients followed-up in our unit were selected respecting inclusion criteria used elsewhere: possible/probable/definite disease; onset-age 18-80years; disease duration from disease duration ≤24months; body mass index (BMI)>20kg/m2; respiratory subscore of the revised ALS functional rating scale (ALSFRS-R)≥11; upright SVC ≥ 70%. We added normal phrenic responses (meanPhrenAmpl, ≥0.4mV). All patients were on riluzole. SVC and meanPhrenAmpl were recorded at study entry (T0) and 24 weeks later (T1). Decays were determined. Sample size was calculated for a treatment effect of 30% on the decay rate. Results: We included 317 ALS patients (191 males, 225 spinal-onset), mean onset-age 59.9 ± 10.7 (31-80)years, mean onset BMI 25.48 ± 3.2 (20.1-35)kg/m2, mean disease duration 10.5 ± 5.6 (1-24)months, mean ALSFRS-R 41.54 ± 4.3 (22-47) and respiratory subscore 11.83 ± 0.38 (11-12). MeanPhrenAmpl and SVC were weakly but significantly correlated at T0 and T1. At T1, MeanPhrenAmpl decayed 16.94 ± 16.45% and SVC 13.5 ± 16.86%. For the proposed drug effect, 174 and 272 patients would be needed to recruit using respectively meanPhrenAmpl and SVC decline as the primary outcome measurement (accepting no dropouts). Discussion: Contrary to SVC, meanPhrenAmpl is non-volitional and not associated with aerosolization risk. Lower recruitment number (98 patients less) would be needed, translating shorter inclusion period, trial length and costs, and probable lower missed data rate. MeanPhrenAmp is an alternative test in ALS clinical trials.

Objetivo: Avaliar o efeito de três tratamentos térmicos pós-polimerização nas alterações dimensionais de duas resinas bis-acrílicas. Materiais e métodos: Com auxílio de um molde metálico foram realizados 100 espécimes (n=10), de acordo com as possíveis combinações entre as resinas bis-acrílicas testadas (Protemp 4 e Structur 3) e os tratamentos térmicos pós-polimerização utilizados (sem tratamento, banho de água a 60ºC, ação de microondas, secador de cabelo convencional e controlo sem envelhecimento). Foram realizadas duas digitalizações, aos 15 e 30 min após o início da mistura, e determinadas as alterações dimensionais ocorridas durante esse período. Após a primeira digitalização os espécimes foram submetidos aos tratamentos térmicos durante 2 min. Posteriormente, foi medido o volume de cada uma das imagens, com recurso a um software para o efeito, permitindo avaliar as alterações dimensionais ocorridas. Os dados foram analisados com testes não paramétricos de Mann-Whitney e Kruskal-Wallis, onde α=0,05. Resultados: Em todos os grupos ocorreu uma contração. Quando comparando os dois materiais testados, não se verificaram diferenças estatisticamente significativas entre eles (p=0,809). O mesmo ocorreu na comparação entre os tipos de tratamentos térmicos pós-polimerização utilizados, não se verificando diferenças estatisticamente significativas (p>0,05) entre os mesmos. Conclusão: Os tratamentos térmicos pós-polimerização parecem não influenciar a contração do material.

Introdução: A instrumentação é um dos passos do tratamento endodôntico, mais especificamente o passo responsável pela remoção mecânica de detritos, micro-organismos e os seus produtos metabólicos do sistema canalar e pela modelagem destes. Este passo pode ser realizado com recurso a limas mecanizadas ou limas manuais. O objetivo deste estudo foi comparar a velocidade de tratamento recorrendo a cada um destes métodos e comparar a prevalência de complicações durante e após a realização de tratamentos endodônticos recorrendo a cada um destes métodos de instrumentação. Materiais e métodos: Foram analisados todos os registos clínicos de tratamentos endodônticos efetuados pelos alunos do mestrado integrado em medicina dentária de quarto e quinto ano entre o ano letivo de 2016/2017 e de 2019/2020, destes foram recolhidos o número de consultas necessárias para concluir cada tratamento realizado, o número de complicações que se deram durante o tratamento e após o término do mesmo e o método escolhido para realizar a instrumentação. Resultados: Não se detetaram diferenças estatisticamente significativas no número de sessões entre as duas técnicas de instrumentação. Relativamente à presença de complicações no decorrer do tratamento, verificou-se uma tendência semelhante entre as técnicas de instrumentação. Em casos de instrumentação mecanizada o tipo de complicação registada mais prevalente foi a fratura de limas e em casos de instrumentação manual foi o abcesso. Não existe registo de complicações após a conclusão dos tratamentos endodônticos em nenhum dos registos clínicos incluídos no estudo. Conclusões: O presente estudo concluí que não existe diferença estatisticamente significante na velocidade de realização de um tratamento endodôntico entre casos realizados com instrumentação manual e com instrumentação mecanizada e que não existe diferença estatisticamente significante na incidência de complicações durante o tratamento endodôntico entre casos realizados com instrumentação manual e casos realizados com instrumentação mecanizada.

Introdução: O tratamento endodôntico tem como objetivo a eliminação de bactérias e os subprodutos. Divide-se em três fases principais: limpeza/modelação, desinfeção e obturação. A realização de radiografias de qualidade sem distorções tem uma extrema importância para o correto diagnóstico e tratamento. Objetivos: Criar uma comparação entre a instrumentação manual versus mecanizada, referente à manutenção da anatomia do canal, posição do ápex, qualidade da obturação e criação de conicidade ideal. Materiais e Métodos: Foram analisados todos os registos clínicos de tratamentos endodônticos efetuados pelos alunos do mestrado integrado em medicina dentária de quarto e quinto ano desde o ano letivo de 2016/2017 até 2019/2020, destes, foram digitalizadas e avaliadas por três alunas as radiografias, inicial e final do tratamento e registado o método de instrumentação realizado. Resultados: Na avaliação da retificação da anatomia do canal, houve uma associação estatisticamente significativa para duas avaliadoras, sendo que a mecanizada respeitou mais a anatomia. Registou-se uma associação significativa entre a ocorrência de transporte apical e a técnica de instrumentação para duas avaliadoras, com a técnica mecanizada a apresentar uma proporção superior de transporte apical. Registou-se uma maior frequência de obtenção de conicidade ideal através da técnica de mecanizada, apesar de não existir uma associação estatisticamente significativa. Verificou-se uma associação estatisticamente significativa entre a qualidade da obturação e a técnica de instrumentação, independentemente da avaliadora, sendo que para os casos bem obturados a frequência é superior nos casos realizados com sistema manual. Conclusão: Em relação à retificação da anatomia a instrumentação mecanizada respeitou mais a anatomia natural, à ocorrência de transporte apical não houve concordância entre avaliadoras, porém ocorreu maioritariamente nos casos de instrumentação mecanizada. Existiu uma diferença estatisticamente significativa, quanto à qualidade de obturação, sendo que com instrumentação manual foi observado uma melhor qualidade de obturação.

Hereditary amyloidosis related to transthyretin (hATTR) is a fatal progressive, autosomal dominant disease caused by mutations in the TTR gene. The most common TTR mutation worldwide is the V30M with a neuropathic phenotype, originating early impairment of small fibres responsible for the autonomic and sensory abnormalities frequently found as the first manifestation of disease. Diagnostic tools to assess autonomic function are essential in the diagnosis of small fibre neuropathy (SFNP) in early stages of disease, allowing an early treatment management.

Skeletal muscle cells (myofibers) are rod-shaped multinucleated cells surrounded by an extracellular matrix (ECM) basal lamina. In contrast to other cell types, nuclei in myofibers are positioned just below the plasma membrane at the cell periphery. Peripheral nuclear positioning occurs during myogenesis and is driven by myofibril crosslinking and contraction. Here we show that peripheral nuclear positioning is triggered by local accumulation of fibronectin secreted by myofibroblasts. We demonstrate that fibronectin via α5-integrin mediates peripheral nuclear positioning dependent on FAK and Src activation. Finally, we show that Cdc42, downstream of restricted fibronectin activation, is required for myofibril crosslinking but not myofibril contraction. Thus we identify that local activation of integrin by fibronectin secreted by myofibroblasts activates peripheral nuclear positioning in skeletal myofibers.

This project, situated from the discipline of design, and motivated by the desire to contribute to the decolonization of public spaces and the collective imaginary, aims to make visible the sociocultural tensions that emanate from the presence of monuments that commemorate the colonial-era in the public sphere. In addressing the issue from the perspective of cultural memory studies and postcolonial theory, it shows how Eurocentric epistemic frameworks give the colonial narrative a rationality that normalizes the domination relations imposed by the empires. In turn, it shows how mediums such as monuments, by remaining intact and glorified, end up projecting in time these power structures and reproducing them in the present. Based on the theory of remediation postulates, the principles of Discursive Design and Speculative Design, and seeking to explore the potential offered by new technologies associated with artificial intelligence and image processing on the web, an application was developed based on a fictional scenario, in which some of the most problematic traits observed in European authorities are exacerbated to the point of satire. This process gave birth to Colombot: Bring Your Favorite Colonialist to Life!, a web application that emulates the incarnation of historical figures of colonialism in an artificial intelligence, which aims to provoke debate by revealing the violent and segregating dimensions of the colonial era.

Numa sociedade marcada pelo cariz científico e tecnológico, a educação em ciência assume um papel fundamental para o desenvolvimento do indivíduo. O ensino das ciências deverá promover a apropriação de conhecimentos e o desenvolvimento de capacidades e atitudes essenciais à vida em sociedade. Este estudo pretende compreender se a implementação da Metodologia de Projecto nas aulas de Ciências da Natureza do 2º ciclo do Ensino Básico permite motivar e envolver os alunos activamente na sua aprendizagem com vista à apropriação de conhecimentos científicos e simultaneamente ao desenvolvimento de competências relacionadas com a autonomia, o pensamento crítico, o espírito de entreajuda e o gosto por aprender. Pretendeuse ainda perceber se o trabalho colaborativo desenvolvido com a investigadora num contexto de supervisão, contribuiu para o desenvolvimento profissional da professora participante. Adoptou-se uma abordagem interpretativa, de tipo qualitativo, seguindo a metodologia de estudo de caso. Como métodos de recolha de dados, realizaram-se entrevistas, efectuaram-se observações no âmbito da implementação da Metodologia de Projecto na sala de aula, e analisaram-se diversos documentos, como o Currículo Nacional do Ensino Básico – Competências Essenciais (DEB, 2001), documentos produzidos colaborativamente pela investigadora e a professora, como planificações e materiais inerentes ao trabalho de projecto e ainda os trabalhos desenvolvidos pelos alunos. Os resultados do estudo apoiam a ideia de que a realização de projectos através da Metodologia de Projecto, contribuíram para a aprendizagem de conteúdos científicos numa perspectiva construtivista da aprendizagem e promoveram o desenvolvimento de competências sociais essenciais a uma cidadania responsável e crítica. O trabalho de projecto proporcionou ainda a integração de outras áreas disciplinares e não disciplinares, constituindo uma metodologia integradora de saberes. Também o trabalho colaborativo com a professora participante em contexto de supervisão, parece ter contribuído para o enriquecimento das práticas pedagógicas, revelando-se um elemento facilitador do desenvolvimento profissional das professoras envolvidas.

The present document intends to demonstrate the validity of the structure and strategy of the game in the artistic process, more than drawing a parallel between game and art. Starting by finding the differences, with regard to the antagonism of the seriousness of the game and the work, it unfolds to show that the game has always been and is always (and will be) present in art (and in life) – Chapter I, The game in art and the art in the game. As soon as we get that out of the way, we set out to explain ‘what game is’ and what constitutes it in its genesis – Chapter II, The polarity of the word game – highlighting its particularities and discovering its system while the echo and coincidence increasingly manifests itself – Chapter III, the peculiarity of the game – resulting in one of the points of greatest interest and attraction, an inherent duplicity that inevitably unites game and art – Chapter IV, The double play / the double game. Thus, we move towards that which is the main figure of this paper, the artist, - Chapter V, The Pawn , the artist=naught - the creative subject who moderates realities that aim at doubles. With a sharp approach to a third realm, one that seems to be out of our control, we conclude this investigation talking about chance and data, - Chapter VI, My niece is cold – supporting an idea that revolves around winning and losing. the moment when the game is over (and cyclically renewed). Can the game be considered as artistic process?

This work project aims to demonstrate the usefulness of QR codes in museum collections, having as a case study the Sculpture Storage Room of the Faculty of Fine Arts of the University of Lisbon. This storage room has works of art that emerged from various contexts, with 99% of the collection consisting of plasters and the rest by other materials. In addition to the objects in the storage room, there are many pieces exhibited throughout the faculty which are also part of the collection. Due to several factors, such as the fact that it is a large collection and is inserted in the academic context, there are some issues that need to be solved as they may be of concern in the future. The most worrying and the one addressed in this dissertation is the degradation factor called dissociation. As identifying the location of objects and their connection to a system is one of the ways to combat dissociation, we propose the implementation of a QR code system, which can be read with the cameras of our smartphones, allowing access to a large quantity of information through public or private websites. These codes allow us to create links between objects inside the storage room and the information associated with them, such as inventory sheets, location of the objects and map, thus solving the existing problem. In addition to its usefulness in organizing and managing the storage room, these codes can also be useful in Faculty corridors as a way of providing additional information to the visitor, making it accessible to everyone.