VI Workshop on Computational Data Analysis and Numerical Methods: Book of Abstracts

The VI Workshop on Computational Data Analysis and Numerical Methods (WCDANM) is going to be held on June 27-29, 2019, in the Department of Mathematics of the University of Beira Interior (UBI), Covilhã, Portugal and it is a unique opportunity to disseminate scientific research related to the areas of Mathematics in general, with particular relevance to the areas of Computational Data Analysis and Numerical Methods in theoretical and/or practical field, using new techniques, giving especial emphasis to applications in Medicine, Biology, Biotechnology, Engineering, Industry, Environmental Sciences, Finance, Insurance, Management and Administration. The meeting will provide a forum for discussion and debate of ideas with interest to the scientific community in general. With this meeting new scientific collaborations among colleagues, namely new collaborations in Masters and PhD projects are expected. The event is open to the entire scientific community (with or without communication/poster)

Physical fitness : identifiers of sport participation and bone health in youth

Physical fitness (PF) assessment is a key tool in monitoring sports performance and health indicators in young people, mainly because PF is related to indicators of both sporting potential and performance, used in signalization, recruitment and surveillance, and bone health. Therefore, this tool may be considered of valuable use to both sport and health professionals. However, there is not a single standardised protocol able to assess the several attributes of PF among young athletes from different sport backgrounds and non-athletes. In this context, this dissertation presents four investigations developed in two major research areas in the evaluation of PF: sports performance and bone health. Regarding sports performance, the reliability of the PF tests, in young athletes from different competitive levels and sports backgrounds were tested. The battery of the FITescola® program proved to be applicable in young athletes of both sexes, constituting a reliable instrument of simple application in the field of sports performance. The discriminatory power of each FITescola® test for signalling young people with sport potential, in consolidated sport organization models, according to gender and age was also analysed. The results showed that PF tests are a valid instrument for signalling young people with sport potential, and that the discriminatory power of the tests varied according to gender and age. In the area of bone health, one investigation was conducted to analyze the relationship between different PF tests and speed of sound (SoS) values in the radius and tibia of young athletes and non-athletes. Different degrees of association were observed between the several PF tests and the radial and tibial SoS values. The degrees of association varied according to gender and athlete status of the participants. The results of this investigation indicate that, for the purpose of monitoring bone health, different PF tests XIX should be applied depending on whether or not young people were athletes. Another analyzed, for the first time, the relationship between vigorous physical activity and SoS in the radius and tibia and whether this relationship was mediated by different PF tests and fatness. The results suggested that some of the effects of vigorous physical activity on radial and tibial SoS were mediated by cardiorespiratory fitness in girls, while the upper and lower muscle strength, speed of displacement and fat mass (%) were found to be mediators in boys. The mediating effect of a PF tests and fat mass (%) on the association of vigorous physical activity with bone health outcomes differed between boys and girls. In summary, this dissertation provides observational scientific evidence on the importance and applicability of PF assessment in the context of competitive sport and, simultaneously, for monitoring bone health among young athletes and non-athletes. These findings may be relevant for present and future interventions in competitive sport as well as in public health.A avaliação da aptidão física é um instrumento fundamental para a monitorização do rendimento desportiva e da saúde, principalmente devido ao facto da aptidão física estar associada a indicadores de potencial desportiva, utilizados no processo de sinalização e recrutamento de jovens, bem como a indicadores de saúde óssea. Desta forma, este instrumento pode ser considerado como uma mais-valia para profissionais da área do desporto e saúde. Todavia, não existe um único protocolo estandardizado capaz de avaliar os vários atributos da aptidão física entre jovens atletas de diferentes modalidades e não atletas. No âmbito do rendimento desportivo, foi testada a reprodutibilidade e a fiabilidade dos testes de aptidão física em jovens atletas de diferentes níveis competitivos. A bateria do programa FITescola® demonstrou ser aplicável em jovens atletas de ambos os sexos, constituindo um instrumento fiável de aplicação simples no âmbito do rendimento desportivo. Adicionalmente, foi analizado o poder discriminativo de cada teste do FITescola® para sinalizar jovens com potencial desportivo, em função do sexo e da idade. Os resultados demonstraram que os testes de aptidão física são um instrumento válido para a sinalização de jovens com potencial desportivo e que o poder discriminatório dos testes variou de acordo com o sexo e a idade. Na área da saúde óssea, foi conduzido uma investigação para analisar a relação entre os diferentes testes de aptidão física e os valores da velocidade do som no rádio e na tíbia, em jovens atletas e não atletas. Os graus de associação variaram em função do sexo e da condição de atleta dos participantes. Os resultados desta investigação indicam que, para efeitos de monitorização da saúde óssea, diferentes testes de aptidão física devem ser aplicados, em função da condição de atleta. Outra XXI investigação analisou, pela primeira vez, a relação entre a atividade física vigorosa e a velocidade do som no rádio e na tíbia, e se esta relação era mediada por diferentes testes de aptidão física e pela massa gorda (%). Os resultados sugerem que nas raparigas, uma parte dos efeitos da atividade física vigorosa na velocidade do som no rádio e na tíbia ere mediada pela aptidão cardiorrespiratória, enquanto, nos rapazes, a força muscular superior e inferior, a velocidade de deslocamento e a massa gorda (%) foram identificados como mediadores desta relação. A presente dissertação fornece evidência científica observacional sobre a importância e aplicabilidade da avaliação da aptidão física tanto no contexto competitivo, como na monitorização da saúde óssea em jovens atletas e não atletas. Estes resultados podem ser relevantes para intervenções presentes e futuras no âmbito do desporto de competição e da saúde pública

Eye quietness and quiet eye in expert and novice golf performance: an electrooculographic analysis

Quiet eye (QE) is the final ocular fixation on the target of an action (e.g., the ball in golf putting). Camerabased eye-tracking studies have consistently found longer QE durations in experts than novices; however, mechanisms underlying QE are not known. To offer a new perspective we examined the feasibility of measuring the QE using electrooculography (EOG) and developed an index to assess ocular activity across time: eye quietness (EQ). Ten expert and ten novice golfers putted 60 balls to a 2.4 m distant hole. Horizontal EOG (2ms resolution) was recorded from two electrodes placed on the outer sides of the eyes. QE duration was measured using a EOG voltage threshold and comprised the sum of the pre-movement and post-movement initiation components. EQ was computed as the standard deviation of the EOG in 0.5 s bins from –4 to +2 s, relative to backswing initiation: lower values indicate less movement of the eyes, hence greater quietness. Finally, we measured club-ball address and swing durations. T-tests showed that total QE did not differ between groups (p = .31); however, experts had marginally shorter pre-movement QE (p = .08) and longer post-movement QE (p < .001) than novices. A group × time ANOVA revealed that experts had less EQ before backswing initiation and greater EQ after backswing initiation (p = .002). QE durations were inversely correlated with EQ from –1.5 to 1 s (rs = –.48 - –.90, ps = .03 - .001). Experts had longer swing durations than novices (p = .01) and, importantly, swing durations correlated positively with post-movement QE (r = .52, p = .02) and negatively with EQ from 0.5 to 1s (r = –.63, p = .003). This study demonstrates the feasibility of measuring ocular activity using EOG and validates EQ as an index of ocular activity. Its findings challenge the dominant perspective on QE and provide new evidence that expert-novice differences in ocular activity may reflect differences in the kinematics of how experts and novices execute skills

Molecular study of Familial Dyslipidaemias by Next Generation Sequencing

Tese de mestrado, Bioquímica (Bioquímica Médica) Universidade de Lisboa, Faculdade de Ciências, 2022Dyslipidemia, a clinical condition defined by an abnormal concentration of lipids in the blood, can have a genetic etiology. Familial dyslipidemias constitute a group of genetically determined conditions, the majority being rare. In addition, these are often associated to serious conditions that can be prevented by the early identification of patients. Hypercholesterolemia promotes atherosclerosis, increasing patients' cardiovascular risk. Neurological manifestations and poor weight progression are frequent complications of hypocholesterolemia, and an increased risk of pancreatitis is often verified in cases of hypertriglyceridemia. This project aimed to identify the genetic cause of dyslipidemia in 96 Portuguese individuals, referred to the Cardiovascular Research Group at the National Health Institute, with a clinical diagnosis of several genetic dyslipidemias associated to different traits: hypercholesterolaemia, hypocholesterolaemia, and hypertriglyceridaemia. The lipid profile of the 96 index cases was determined for biochemical characterization. The molecular study of individuals was performed by Next Generation Sequencing with a customised target panel of 57 genes involved in lipid metabolism. Molecular diagnosis was provided after analysis of 18 genes strongly associated with several familial dyslipidemias. Rare variants detected were confirmed by PCR and Sanger Sequencing. A definite cause of monogenic dyslipidemia was established in 35 cases: 22 individuals were diagnosed with familial hypercholesterolaemia, 3 with familial hypobetalipoproteinemia, 2 with familial chylomicronemia syndrome, 7 with multifactorial chylomicronemia, and one with autosomal recessive hypertriglyceridemia. Moreover, several variants with uncertain significance were found by NGS during this project, the majority lacking functional data. As these variants can constitute the cause of disease in some cases, functional studies will be essential to assess variant’s pathogenicity. This work allowed an early and correct identification of Portuguese patients with different familial dyslipidemias, thus providing guidance for pharmacological treatment and lifestyle adaptations to reduce the chance of suffering disease complications, improving this way patients’ prognosis

Genetic susceptibility to myeloproliferative neoplasms and therapeutic efficacy

RESUMO: As neoplasias mieloproliferativas são classicamente divididas em neoplasias mieloproliferativas BCR-ABL1 (cromossoma Philadelphia) positivas, como é o caso da leucemia mieloide crónica, e BCR-ABL1 negativas, incluindo a policitémia vera, a trombocitémia essencial e a mielofibrose primária. Estas entidades nosológicas têm origem na transformação maligna das stem-cells hematopoiéticas, levando a amplificação anormal e à proliferação das células das linhagens mielóides. A diversidade fenotípica das neoplasias mieloproliferativas Philadelphia negativas resulta da combinação de mutações somáticas já identificadas e caracterizadas, variabilidade genética hereditária, regulação pós-genética e condicionantes individuais. De acordo com a literatura, vários polimorfismos genéticos foram identificados, podendo influenciar os mecanismos de apoptose e de capacidade de reparação do DNA, comprometendo a transcrição genética e/ou a atividade celular, conferindo predisposição genética para a doença, incluindo o caso das neoplasias mieloproliferativas, e condicionando a resposta terapêutica, a evolução clínica e o prognóstico. O presente trabalho teve como objetivo caraterizar a população portuguesa de acordo com o tipo de neoplasia mieloproliferativa Philadelphia negativa, a sua prevalência e a presença da mutação JAK2, dando especial ênfase a alguns doentes em particular; investigar o papel dos polimorfismos nos genes envolvidos nas vias de apoptose e de reparação por excisão de bases na susceptibilidade para estas doenças e, juntamente com outros fatores de risco, na sobrevivência, evolução clínica e prognóstico. Foram realizados estudos caso-controlo numa amostragem de 133 doentes Portugueses caucasianos e 281 indivíduos saudáveis correspondentes e foram selecionados nove e oito polimorfismos de genes envolvidos nas vias de apoptose e de reparação por excisão de bases, respectivamente, que foram genotipados utilizando a técnica de Polymerase Chain Reaction em tempo real. A análise estatística foi realizada com recurso ao software SPSS versão 22.0. Os resultados deste estudo revelaram uma distribuição dos doentes por patologia de 60,2% com trombocitémia essencial, 29,3% com policitémia vera e 10,5% com mielofibrose primária, um discreto predomínio nas mulheres e 75,0% dos doentes positivos para a presença da mutação JAK2 V617F, evidenciando uma incidência mais elevada na trombocitémia essencial e mais reduzida na policitémia vera, relativamente ao esperado. Entre os doentes, alguns casos em particular foram destacados e apresentados nesta tese: o caso de um doente com policitémia vera JAK2 exão 12 positivo, apresentando uma nova mutação - c.1605G> T (p.Met535Ile) - associada a outra mutação já anteriormente descrita, evidenciando um fenótipo clínico atípico; dois doentes com trombocitémia essencial, com suspeita da coexistência rara da mutação JAK2 V617F e da translocação BCR-ABL1; e um doente com leucemia mieloide crónica,apresentando uma nova mutação no domínio kinase BCR-ABL1 - c.839T> G (p.Val280Gly) - que poderá estar associada a resistência ao imatinib. Quanto aos polimorfismos investigados, os nossos resultados revelaram potenciais associações entre alguns dos polimorfismos e a susceptibilidade individual para estas doenças, sugerindo o potencial envolvimento de polimorfismos do gene CASP9 (Phe136Phe) e dos genes XRCC1_399 (Gln399Arg) e MUTYH (Gln335His), após estratificação por patologia para os doentes com trombocitémia essencial e quando se tratam de mulheres. Nos doentes JAK2 positivos verificou-se uma associação com os polimorfismos do gene CASP9 (Phe136Phe) e do gene XRCC1_399 (Gln399Arg). Nos genes de reparação por excisão de bases, a combinação de alelos também demonstrou associação com doença para um haplogrupo específico. Em relação à evolução clínica dos doentes sob tratamento, na maioria dos casos com hidroxiureia, de acordo com nossos resultados: 17 doentes apresentaram progressão para mielofibrose secundária/leucemia mieloide aguda, influenciando a sobrevivência e estando associada à exposição a agentes citoredutores. Nestes doentes, houve também evidência global de associação com polimorfismos do gene CASP8 (3'UTR) e do gene XRCC1_194 (Arg194Trp), e após estratificação para trombocitémia essencial com polimorfismos do gene CASP9 (Arg173His) e dos genes APEX1 (Asp148Glu) e XRCC1_194 (Arg194Trp); 11 doentes desenvolveram uma neoplasia não mieloide primária de novo, evidenciando uma associação global com polimorfismos do gene CASP8 (Asp270His) e do gene XRCC1_399 (Gln399Arg); 22 doentes apresentaram eventos trombóticos e uma associação global com polimorfismos do gene XRCC1_399 (Gln399Arg). Os resultados apresentados na presente dissertação ajudaram a caracterizar uma população de doentes com neoplasias mieloproliferativas Philadelphia negativas, podendo refletir a realidade portuguesa, e revelaram o papel potencial de determinados polimorfismos e outros fatores na susceptibilidade para a doença e na evolução clínica dos doentes sob terapêutica, com impacto prognóstico. Embora sejam necessários estudos mais alargados para confirmar estes resultados, estes novos dados podem contribuir para um melhor conhecimento da fisiopatologia e, no futuro, para uma escolha mais racional e eficiente das estratégias terapêuticas a adotar nestas patologias.ABSTRACT: Myeloproliferative neoplasms are classically divided into BCR-ABL1 (Philadelphia chromosome) positive chronic myeloid leukemia and BCR-ABL1 negative myeloproliferative neoplasms, including polycythemia vera, essential thrombocythemia and primary myelofibrosis. These disorders have origin from the malignant transformation of a hematopoietic stem-cell, leading to abnormal amplification and proliferation of myeloid lineages. The phenotypic diversity of Philadelphia chromosome negative myeloproliferative neoplasms results from the combination of somatic mutations already identified and characterized, inherited genetic variability, postgenetic regulation, and individual conditioners. According to the literature, several genetic polymorphisms have been identified, which may influence the apoptosis mechanisms and the DNA repair capacity, compromising genetic transcription and/or cell function, conferring genetic predisposition to disease, including myeloproliferative disorders, and conditioning the therapeutic response, the clinical outcome and prognosis. The present work had the purpose of characterize the Portuguese population according to the type of Philadelphia chromosome negative myeloproliferative neoplasm, its prevalence and the presence of JAK2 mutation, with special emphasis on some particular patients; investigate the role of polymorphisms in genes involved in apoptosis and base excision repair pathways in these disorders susceptibility and, along with other risk factors, in survival, clinical outcome and prognosis. Case-control studies were carried out in a Caucasian Portuguese sample of 133 patients and 281 matched control subjects, nine and eight polymorphisms of genes involved in apoptosis and base excision repair pathways, respectively, were selected and genotyped using real time polymerase chain reaction technique and statistical analysis was performed with SPSS version 22.0. The results from this study revealed a pathology distribution of 60.2% of patients with essential thrombocythemia, 29.3% with polycythemia vera and 10.5% with primary myelofibrosis, with a discrete predominance in females, and a total of 75.0% of patients positive for the presence of the JAK2 V617F mutation, with an increased incidence in essential thrombocythemia and a decreased incidence in polycythemia vera patients than expected. Among the patients, some particular cases were highlighted and presented in this thesis, namely the case of a polycythemia vera patient JAK2 exon 12 positive, presenting a novel mutation – c.1605G>T (p.Met535Ile) - associated with another mutation previously described, evidencing an atypical clinical phenotype; two patients with essential thrombocythemia, with suspicion of the rare coexistence of JAK2 V617F mutation and BCR-ABL1 translocation; and a patient with chronic myeloid leukemia, presenting a new BCR-ABL1 mutation kinase domain mutation – c.839T>G (p.Val280Gly) – which might be associated with resistance to imatinib. Concerning the polymorphisms investigated, our results revealed potential associations between some polymorphisms and individual susceptibility to these disorders, suggesting the potential involvement of CASP9 (Phe136Phe) gene and XRCC1_399 (Gln399Arg) and MUTYH (Gln335His) genes polymorphisms after stratification by pathology diagnosis for essential thrombocythemia patients and when they are women. When patients are JAK2 positive an association with CASP9 (Phe136Phe) gene and XRCC1_399 (Gln399Arg) gene polymorphisms was found. In base excision repair genes, combination of alleles also demonstrated an association with the disease for one specific haplogroup. Regarding the clinical outcome in patients under treatment, the majority of them with hydroxyurea, according to our results: 17 patients showed progression to secondary myelofibrosis/acute myeloid leukemia, influencing survival and being associated with exposure to cytoreductive agents. In these patients, there was also global evidence of association with CASP8 (3’UTR) gene and XRCC1_194 (Arg194Trp) gene polymorphisms, and after stratification for essential thrombocythemia with CASP9 (Arg173His) gene, and APEX1 (Asp148Glu) and XRCC1_194 (Arg194Trp) genes polymorphisms; 11 patients developed a new primary nonmyeloid neoplasm, evidencing a global association with CASP8 (Asp270His) gene and XRCC1_399 (Gln399Arg) gene polymorphisms; 22 patients presented thrombotic events and a global association with XRCC1_399 (Gln399Arg) gene polymorphisms. The results shown in the present dissertation helped to characterize a population of Philadelphia negative myeloproliferative neoplasms patients that could reflect Portuguese reality, and have revealed the potential role of polymorphisms and other factors in disease susceptibility and clinical outcome of patients under treatment, with prognostic impact. Although larger studies are required to confirm these results, these new data may contribute to a best knowledge of the pathophysiology and, in the future, to a more rational and efficient choice of therapeutic strategies to be adopted in these disorders

Cardiovascular Effects of Relaxin-2: Therapeutic Potential and Future Perspectives

A hormona Relaxina-2 tem vindo a destacar-se como um elemento promissor na regulação da fisiologia do sistema cardiovascular. Ao atuar através do receptor de peptídeo da família da Relaxina 1 (RXFP1), produz diferentes efeitos, desde da indução da vasodilatação, prevenção da fibrose, redução da inflamação e do stress oxidativo, até à estimulação da angiogénese. Tanto a Relaxina-2 como a sua forma humana recombinante, conhecida como Serelaxina, têm sido alvo de investigação em estudos pré-clínicos e clínicos como uma potencial terapêutica para doenças cardiovasculares, em particular para a insuficiência cardíaca, uma vez que esta permanece como uma das principais causas de morbidade e mortalidade em todo o mundo. No entanto, os resultados dos ensaios clínicos têm sido inconsistentes e ainda são necessários mais estudos para se compreender o verdadeiro potencial da Relaxina-2. Esta revisão oferece uma visão geral do uso da Serelaxina em ensaios clínicos passados, bem como das direções futuras no desenvolvimento de miméticos da Relaxina, que são particularmente interessantes, pois têm o potencial de oferecer novas opções terapêuticas para pacientes com insuficiência cardíaca.The hormone Relaxin-2 has emerged as a promising player in regulating the physiology of the cardiovascular system. It exerts its effects through the Relaxin Family Peptide Receptor 1 (RXFP1) with multiple functions including induction of vasodilation, prevention of fibrosis, reduction of inflammation and oxidative stress and stimulation of angiogenesis. The potential of Relaxin-2, or its recombinant human form known as Serelaxin, has been investigated in both preclinical and clinical studies as a potential therapy for cardiovascular diseases, in particular for heart failure, which remains a significant cause of morbidity and mortality worldwide. However, evidence from past clinical trials has been inconsistent and further research is needed to fully understand the potential applications of Relaxin-2. This review provides an overview of the use of Serelaxin in clinical trials, as well as future directions in the development of Relaxin mimetics, which could potentially offer new therapeutic options for patients with Heart Failure

Role of tomm40’523 – apoe haplotypes in alzheimer’s disease etiology – from clinics to mitochondria

RESUMO: TOMM40’523 é um polimorfismo poli-T do gene TOMM40 que foi descrito por Roses et al. como estando associado com o risco e idade de início da doença de Alzheimer (DA). Entretanto, e com base na distribuição do número de timinas, três tipos de alelos foram estabelecidos: “short” (S, ≤ 19), “long” (L, 20– 29) e “very long” (VL, ≥ 30). Desde a descoberta inicial de Roses et al. vários estudos encontraram associações entre o polimorfismo TOMM40’ 523 e características relacionadas com a DA entre elas, idade de início e risco de DA, alterações na morfologia cerebral e cognição, enquanto outros estudos não conseguiram replicar estas associações. Além do mais, este polimorfismo foi pouco estudado em populações com défice cognitivo ligeiro (DCL) e tanto quanto sabemos nenhum destes estudos se debruçou na relação entre o polimorfismo TOMM40’ 523 e o risco e tempo de conversão de DCL para DA. Assim, na primeira parte do trabalho aqui apresentado o nosso principal objetivo foi investigar a relação do polimorfismo TOMM40’ 523 com o risco e tempo de conversão de DCL para DA, bem como replicar a associação inicial descrita por Roses et al. com o risco e idade de início da DA. Em segundo lugar, explorámos a relação entre este polimorfismo e os níveis de biomarcadores de DA no líquido cefalorraquidiano (LCR), nomeadamente Ab42, Tau total e fosfo-Tau. Para este efeito, procedemos à genotipagem para o polimorfismo TOMM40’ 523 em 147 pacientes com DA, 102 pacientes com DCL e 105 controlos cognitivamente normais. Os pacientes DCL foram subdivididos em dois grupos distintos: um grupo de pacientes DCL que converteram para AD (DCL-C) e um grupo de pacientes que permaneceu cognitivamente estável (DCLNC). Começámos neste estudo por demonstrar que os doentes DCL que não converteram (DCL-NC) e os doentes que converteram (DCL-C) apresentavam uma distribuição distinta do número de timinas neste polimorfismo, sendo o alelo L significativamente mais frequente no grupo DLC-C. Posteriormente, avaliámos como é que esta diferença afetava o risco de conversão de DCL para DA e verificámos que a presença de pelo menos um alelo L aumentava significativamente o risco de conversão de DCL para DA. Contudo, quando tido em conta o alelo ε4 do gene APOE, verificámos que tanto o alelo L como alelo ε4 perdiam significância no modelo de conversão (p > 0.05). Então decidimos estudar o haplótipo APOE ε4-TOMM40ʹ 523 L e observámos que doentes com este haplótipo apresentavam um risco significativamente maior de conversão de DCL para DA e menores tempos de conversão. Verificou-se também uma associação significativa entre este haplótipo e um perfil de biomarcadores compatível com DA, nomeadamente menores níveis de Ab42 e níveis mais altos de Tau total e fosfo-Tau. Adicionalmente, verificamos que o haplótipo APOE ε4-TOMM40ʹ 523 L estava significativamente associado com um maior risco de desenvolver DA e com menor idade de início da doença. O gene TOMM40 codifica a proteína TOM40 (Translocase da membrana externa, 40 kD) que forma o canal na membrana externa da mitocôndria através do qual a maioria das proteínas codificadas no citoplasma entram na mitocôndria. Sendo a importação de proteínas essencial para a biogénese e funcionamento da mitocôndria, não é de surpreender que a proteína TOM40 seja essencial para os seres eucarióticos, e que modificações nesta proteína possam eventualmente levar a disfunção mitocondrial. A disfunção mitocondrial é um evento bem caracterizado na DA. Tendo isto em conta, colocámos a hipótese de que o polimorfismo TOMM40’ 523 poderia ter um papel importante na disfunção mitocondrial e patogénese da DA. Utilizando células mononucleares do sangue periférico (PBMCs) de doentes com DA, estudámos o impacto deste polimorfismo em diferentes parâmetros mitocondriais como função, estrutura e apoptose. As PBMCs foram obtidas de doentes homozigóticos para os alelos S, L e VL, sendo denominados posteriormente como grupos S,L e VL. Neste estudo, podémos observar que o grupo VL apresentava níveis significativamente mais elevados da proteína TOM40, semelhante potencial de membrana mitocondrial, maiores níveis de proteínas de fissão mitocondrial e uma menor ativação da caspase 3 quando comparado com o grupo S. Apesar destes dois últimos parâmetros não alcançarem significância estatística, estes dados reforçam a hipótese de que o aumento nos níveis de TOM40, tal como observado também por Zeitlow et al., poderão ser protetores para mitocôndria. Contudo estes dados têm de ser replicados em experiências futuras. Em jeito de sumário, neste trabalho pretendemos estudar o potencial papel do polimorfismo TOMM40’523 no risco de desenvolver DA, bem como o seu envolvimento na fisiopatologia desta doença via disfunção mitocondrial, numa perspetiva “ da clinica para a mitocôndria”.ABSTRACT: TOMM40’523 is a poly-T polymorphism of the gene TOMM40 which was reported by Roses et al. to be associated with risk and age of onset (AOO) of Alzheimer’s Disease (AD) nearly a decade ago. Meanwhile, based on the distribution behavior of the number of thymine (T) residues, three categories (alleles) of repeat length were established: short (S, ≤ 19), long (L, 20– 29) and very long (VL, ≥ 30). Since the original discovery by Roses et al. multiple studies found associations between TOMM40’ 523 and LOAD-related features, such as AOO and risk of AD, brain structure and cognition, while other studies could not replicate these associations. Moreover, this polymorphism has been poorly addressed in mild cognitive impairment cohorts (MCI) and as far as we know, none of these studies fully addressed the connection between TOMM40’ 523 polymorphism and the risk and time of conversion from MCI to AD. Therefore, in the first part of this work our aim was to investigate the relationship between TOMM40’ 523 polymorphism with the risk and conversion time from MCI to AD, and replicate the association of TOMM40’523 polymorphism with AOO and risk of AD. Secondly, the association between TOMM40’ 523 genotype and AD cerebrospinal fluid (CSF) biomarkers, particularly Ab42, t-Tau and p-Tau, was also explored. For this purpose, 147 AD patients, 102 MCI patients and 105 cognitively normal controls were genotyped for poly-T polymorphism. MCI patients were subdivided into 2 groups, the group of patients that converted to AD (MCI-AD) and the group of those that remained stable (MCI-S). We first demonstrated that MCI non-converters (MCI-S) and converters (MCI-AD) had a different poli-T distribution, where the L allele was significantly more frequent in the MCI-AD group. We further evaluated how this difference impacted the risk of conversion and found that having at least one L allele significantly increased the risk of conversion from MCI to AD. However, when adjusted for the presence of APOE ε4 allele, both the L allele and ε4 allele lost significance in the model (p > 0.05). We then analysed the APOE ε4-TOMM40ʹ 523 L haplotype and observed that patients carrying this haplotype had significantly higher risk and mean lower times of conversion to AD. This haplotype was also significantly associated with a biomarker profile compatible with AD namely, significantly lower levels of Ab42 and higher levels of t-Tau and p-Tau. Similar results were observed for AD where ε4-L haplotype carriers where associated with a significantly higher risk of AD and lower AOO of AD patients. TOMM40 gene encodes the Tom40 protein (translocase of the outer mitochondrial membrane, 40 kD) which forms the channel subunit of the outer mitochondrial membrane protein complex through which the majority of nuclear-encoded proteins enter mitochondria. As the import of mitochondrial proteins into mitochondria is essential for biogenesis and functioning of mitochondria, it is not surprising that TOM40 is essential for life in eukaryotic organisms and that modifications in this protein could lead to mitochondrial dysfunction. Mitochondria dysfunction is a well characterized event in AD. Considering this, it was hypothesized that TOMM40’ 523 polymorphism could have a role on AD through mitochondrial dysfunction. However, the few studies performed so far did not reach clear conclusions. Using Peripheral Blood Mononuclear Cells (PBMCs) from AD patients, we addressed the impact of this polymorphism on different mitochondrial features, such as function, structure and apoptosis. We obtained PBMCs from patients homozygous for S, L and VL TOMM40’ 523 polymorphisms, which are thereafter called S, L and VL groups. In this study, we observed that VL group had significant higher levels of TOM40 than S group, similar mitochondrial membrane potential, higher mitochondrial fission protein levels and lower caspase activation. Although these two last parameters did not reach statistical significance, our data reinforce the hypothesis thatincreased levels of TOM40, as have been observed by Zeitlow et al.seem to be protective to mitochondria, however these experiments should be replicated. In summary in this work we aimed to study the potential role of TOMM40’523 as a risk gene for AD and its involvement in AD pathophysiology through mitochondrial dysfunction, under the perspective “from clinics to mitochondria”

Book of abstracts and proceedings. 44th international conference of the stress, trauma, anxiety, and resilience society (STAR)

Stress and anxiety situations are increasing problems in recent years. In fact, anxiety disorders take first place in the ranking of global psychopathology, followed by depression. Many of these situations are traumatic, and it is essential to develop resilience to make people and communities more resilient to prevent these situations. Several factors have contributed to this, including the high demand in the professional activity, the breakneck pace people have to live and make decisions, the high competitiveness, the lack of social support, the lack of control in many situations, the uncertainty and the insecurity. Recently, it has also highlighted the economic crisis and unemployment, the healthy problems, namely because of the Covid pandemic, and the war in ukraine, as major factors for stress, anxiety and trauma that many people have. It is increasingly important that people know how to handle these situations, through their coping strategies, and resilience skills.info:eu-repo/semantics/publishedVersio