Estudos de neotectónica na ilha de São Miguel: uma contribuição para o estudo do risco sísmico no arquipélago dos Açores

Tese de Doutoramento, Geologia (Vulcanologia), 21 de Março de 2014, Universidade dos Açores.

Geologia estrutural da região Povoação-Nordeste (Ilha de São Miguel, Açores)

Dissertação de Mestrado, Vulcanologia e Riscos Geológicos, 10 de Novembro de 2005, Universidade dos Açores.

O uso do smartphone na avaliação do risco de queda associado ao envelhecimento

Introdução: O declínio do equilíbrio, da força dos membros inferiores e o medo de cair são fatores de risco de queda associados ao envelhecimento e a sua avaliação pode ser realizada pelo teste One Leg Standing (OLS), Sit to Stand (STS) e pela Falls Eficacy Scale (FES), respetivamente. As aplicações para smartphone constituem uma alternativa para a avaliação dos fatores de risco de queda no envelhecimento. Objetivo: Analisar a capacidade de uma aplicação para smartphone na avaliação dos testes STS, OLS e FES. Metodologia: Realizou-se um estudo analítico numa amostra de 27 voluntários com idade ≥ 60 anos. Realizaram-se os testes STS, OLS e a FES (versão iconográfica, apresentada no smartphone). Os dados foram recolhidos simultaneamente por um smartphone e pelo Qualisys Motion Capture Systems associado a uma plataforma de forças. Foi utilizado o r de Pearson ou Spearman para analisar as possíveis correlações. Resultados: No STS obteve-se uma correlação muito forte (rp=0.97) no número de repetições de ciclos Sit Stand Sit (SLS) e forte na duração média do SLS (rp=0.85) e das subfases Sit to Stand (rp=0.69) e Stand to Sit (rp=0.778), com p<0.001. As medidas de inclinação do tronco apresentaram correlações fortes, com exceção do ângulo inicial (p≥0.05). No OLS, verificou-se uma correlação moderada entre o deslocamento do centro de pressão peak to peak médio-lateral (rs=0.45; p=0.017) e antero-posterior (rs=0.39; p=0.046), root mean square médio-lateral (rs=0.39; p=0.046) e antero-posterior (rs=0.46; p=0.017) e área do estatocinesiograma (rs=0.45; p=0.018). Na FES obteve-se uma correlação moderada em três categorias: ‘tomar banho/duche’ (rs=0.49; p=0.010), ‘deitar/levantar da cama (rs=0.43; p=0.024) e ‘chegar aos armários’ (rs=0.38; p=0.050). Conclusão: A aplicação para smartphone parece avaliar corretamente os ciclos e a variação da inclinação do tronco no STS, porém parece necessitar de ser reajustada na FES e na velocidade do deslocamento do centro de pressão, no OLS.

Influence of environmental temperature and humidity on the acute ventilatory response to exercise in asthmatic adolescents

Asthma is a chronic inflammatory disorder of the respiratory airways affecting people of all ages, and constitutes a serious public health problem worldwide (6). Such a chronic inflammation is invariably associated with injury and repair of the bronchial epithelium known as remodelling (11). Inflammation, remodelling, and altered neural control of the airways are responsible for both recurrent exacerbations of asthma and increasingly permanent airflow obstruction (11, 29, 34). Excessive airway narrowing is caused by altered smooth muscle behaviour, in close interaction with swelling of the airway walls, parenchyma retractile forces, and enhanced intraluminal secretions (29, 38). All these functional and structural changes are associated with the characteristic symptoms of asthma – cough, chest tightness, and wheezing –and have a significant impact on patients’ daily lives, on their families and also on society (1, 24, 29). Recent epidemiological studies show an increase in the prevalence of asthma, mainly in industrial countries (12, 25, 37). The reasons for this increase may depend on host factors (e.g., genetic disposition) or on environmental factors like air pollution or contact with allergens (6, 22, 29). Physical exercise is probably the most common trigger for brief episodes of symptoms, and is assumed to induce airflow limitations in most asthmatic children and young adults (16, 24, 29, 33). Exercise-induced asthma (EIA) is defined as an intermittent narrowing of the airways, generally associated with respiratory symptoms (chest tightness, cough, wheezing and dyspnoea), occurring after 3 to 10 minutes of vigorous exercise with a maximal severity during 5 to 15 minutes after the end of the exercise (9, 14, 16, 24, 33). The definitive diagnosis of EIA is confirmed by the measurement of pre- and post-exercise expiratory flows documenting either a 15% fall in the forced expiratory volume in 1 second (FEV1), or a ≥15 to 20% fall in peak expiratory flow (PEF) (9, 24, 29). Some types of physical exercise have been associated with the occurrence of bronchial symptoms and asthma (5, 15, 17). For instance, demanding activities such as basketball or soccer could cause more severe attacks than less vigorous ones such as baseball or jogging (33). The mechanisms of exercise-induced airflow limitations seem to be related to changes in the respiratory mucosa induced by hyperventilation (9, 29). The heat loss from the airways during exercise, and possibly its post-exercise rewarming may contribute to the exercise-induced bronchoconstriction (EIB) (27). Additionally, the concomitant dehydration from the respiratory mucosa during exercise leads to an increased interstitial osmolarity, which may also contribute to bronchoconstriction (4, 36). So, the risk of EIB in asthmatically predisposed subjects seems to be higher with greater ventilation rates and the cooler and drier the inspired air is (23). The incidence of EIA in physically demanding coldweather sports like competitive figure skating and ice hockey has been found to occur in up to 30 to 35% of the participants (32). In contrast, swimming is often recommended to asthmatic individuals, because it improves the functionality of respiratory muscles and, moreover, it seems to have a concomitant beneficial effect on the prevalence of asthma exacerbations (14, 26), supporting the idea that the risk of EIB would be smaller in warm and humid environments. This topic, however, remains controversial since the chlorified water of swimming pools has been suspected as a potential trigger factor for some asthmatic patients (7, 8, 20, 21). In fact, the higher asthma incidence observed in industrialised countries has recently been linked to the exposition to chloride (7, 8, 30). Although clinical and epidemiological data suggest an influence of humidity and temperature of the inspired air on the bronchial response of asthmatic subjects during exercise, some of those studies did not accurately control the intensity of the exercise (2, 13), raising speculation of whether the experienced exercise overload was comparable for all subjects. Additionally, most of the studies did not include a control group (2, 10, 19, 39), which may lead to doubts about whether asthma per se has conditioned the observed results. Moreover, since the main targeted age group of these studies has been adults (10, 19, 39), any extrapolation to childhood/adolescence might be questionable regarding the different lung maturation. Considering the higher incidence of asthma in youngsters (30) and the fact that only the works of Amirav and coworkers (2, 3) have focused on this age group, a scarcity of scientific data can be identified. Additionally, since the main environmental trigger factors, i.e., temperature and humidity, were tested separately (10, 28, 39) it would be useful to analyse these two variables simultaneously because of their synergic effect on water and heat loss by the airways (31, 33). It also appears important to estimate the airway responsiveness to exercise within moderate environmental ranges of temperature and humidity, trying to avoid extreme temperatures and humidity conditions used by others (2, 3). So, the aim of this study was to analyse the influence of moderate changes in air temperature and humidity simultaneously on the acute ventilatory response to exercise in asthmatic children. To overcome the above referred to methodological limitations, we used a 15 minute progressive exercise trial on a cycle ergometer at 3 different workload intensities, and we collected data related to heart rate, respiratory quotient, minute ventilation and oxygen uptake in order to ensure that physiological exercise repercussions were the same in both environments. The tests were done in a “normal” climatic environment (in a gymnasium) and in a hot and humid environment (swimming pool); for the latter, direct chloride exposition was avoided.

Intra- and interspecific mineral composition variability of commercial instant coffees and coffee substitutes: contribution to mineral intake

The present paper reports the amount and estimated daily mineral intake of nine elements (Ca, Mg, K, Na, P, Fe, Mn, Cr and Ni) in commercial instant coffees and coffee substitutes (n = 49). Elements were quantified by high-resolution continuum source flame (HR-CS-FAAS) and graphite furnace (HR-CS-GFAAS) atomic absorption spectrometry, while phosphorous was evaluated by a standard vanadomolybdophosphoric acid colorimetric method. Instant coffees and coffee substitutes are rich in K, Mg and P (>100 mg/100 g dw), contain Na, Ca and Fe in moderate amounts (>1 mg/100 g), and trace levels of Cr and Ni. Among the samples analysed, plain instant coffees are richer in minerals (p < 0.001), except for Na and Cr. Blends of coffee substitutes (barley, malt, chicory and rye) with coffee (20–66%) present intermediate amounts, while lower quantities are found in substitutes without coffee, particularly in barley. From a nutritional point of view the results indicate that the mean ingestion of two instant beverages per day (total of 4 g instant powder), either with or without coffee, cannot be regarded as important sources of minerals to the human diet, although providing a supplementation of some minerals, particularly Mg and Mn in instant coffees. Additionally, and for authentication purposes, the correlations observed between some elements and the coffee percentage in the blends, with particular significance for Mg amounts, provides a potential tool for the estimation of coffee in substitute blends.

Avaliação dos níveis de atividade física e capacidade aeróbia estimada em estudantes universitários

Mestrado em Fisioterapia

Habitat predictive modelling of demersal fish species in the Azores

Dissertação de Mestrado, Estudos Integrados dos Oceanos, 25 de Março de 2013, Universidade dos Açores.

Dietary patterns and risk of oral cancer: a case-control study in São Paulo, Brazil

OBJECTIVE: To analyze the association between dietary patterns and oral cancer. METHODS: The study, part of a Latin American multicenter hospital-based case-control study, was conducted in São Paulo, Southeastern Brazil, between November 1998 and March 2002 and included 366 incident cases of oral cancer and 469 controls, frequency-matched with cases by sex and age. Dietary data were collected using a food frequency questionnaire. The risk associated with the intake of food groups defined a posteriori, through factor analysis (called factors), was assessed. The first factor, labeled "prudent," was characterized by the intake of vegetables, fruit, cheese, and poultry. The second factor, "traditional," consisted of the intake of rice, pasta, pulses, and meat. The third factor, "snacks," was characterized as the intake of bread, butter, salami, cheese, cakes, and desserts. The fourth, "monotonous," was inversely associated with the intake of fruit, vegetables and most other food items. Factor scores for each component retained were calculated for cases and controls. After categorization of factor scores into tertiles according to the distribution of controls, odds ratios and 95% confidence intervals were calculated using unconditional multiple logistic regression. RESULTS: "Traditional" factor showed an inverse association with cancer (OR=0.51; 95% CI: 0.32; 0.81, p-value for trend 0.14), whereas "monotonous" was positively associated with the outcome (OR=1.78; 95% CI: 1.78; 2.85, p-value for trend <0.001). CONCLUSIONS: The study data suggest that the traditional Brazilian diet, consisting of rice and beans plus moderate amounts of meat, may confer protection against oral cancer, independently of any other risk factors such as alcohol intake and smoking.

Efeitos do treinamento aeróbio intervalado periodizado sobre os parâmetros antropométricos, bioquímicos e clínicos em portadores de síndrome metabólica

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

OsRMC, a negative regulator of salt stress response in rice, is regulated by two AP2/ERF transcription factors

High salinity causes remarkable losses in rice productivity worldwide mainly because it inhibits growth and reduces grain yield. To cope with environmental changes, plants evolved several adaptive mechanisms, which involve the regulation of many stress-responsive genes. Among these, we have chosen OsRMC to study its transcriptional regulation in rice seedlings subjected to high salinity. Its transcription was highly induced by salt treatment and showed a stress-dose-dependent pattern. OsRMC encodes a receptor-like kinase described as a negative regulator of salt stress responses in rice. To investigate how OsRMC is regulated in response to high salinity, a salt-induced rice cDNA expression library was constructed and subsequently screened using the yeast one-hybrid system and the OsRMC promoter as bait. Thereby, two transcription factors (TFs), OsEREBP1 and OsEREBP2, belonging to the AP2/ERF family were identified. Both TFs were shown to bind to the same GCC-like DNA motif in OsRMC promoter and to negatively regulate its gene expression. The identified TFs were characterized regarding their gene expression under different abiotic stress conditions. This study revealed that OsEREBP1 transcript level is not significantly affected by salt, ABA or severe cold (5 °C) and is only slightly regulated by drought and moderate cold. On the other hand, the OsEREBP2 transcript level increased after cold, ABA, drought and high salinity treatments, indicating that OsEREBP2 may play a central role mediating the response to different abiotic stresses. Gene expression analysis in rice varieties with contrasting salt tolerance further suggests that OsEREBP2 is involved in salt stress response in rice.

Expression of YAP4 in Saccharomyces cerevisiae under osmotic stress

YAP4, a member of the yeast activator protein (YAP) gene family, is induced in response to osmotic shock in the yeast Saccharomyces cerevisiae. The null mutant displays mild and moderate growth sensitivity at 0.4 M and 0.8 M NaCl respectively, a fact that led us to analyse YAP4 mRNA levels in the hog1 (high osmolarity glycerol) mutant. The data obtained show a complete abolition of YAP4 gene expression in this mutant, placing YAP4 under the HOG response pathway. YAP4 overexpression not only suppresses the osmosensitivity phenotype of the yap4 mutant but also relieves that of the hog1 mutant. Induction, under the conditions tested so far, requires the presence of the transcription factor Msn2p, but not of Msn4p, as YAP4 mRNA levels are depleted by at least 75% in the msn2 mutant. This result was further substantiated by the fact that full YAP4 induction requires the two more proximal stress response elements. Furthermore we find that GCY1, encoding a putative glycerol dehydrogenase, GPP2, encoding a NAD-dependent glycerol-3-phosphate phosphatase, and DCS2, a homologue to a decapping enzyme, have decreased mRNA levels in the yap4 -deleted strain. Our data point to a possible, as yet not entirely understood, role of the YAP4 in osmotic stress response.

A eficácia entre duas intervenções na Síndrome do Canal Cárpico

A Síndrome do Canal Cárpico (SCC) é a neuropatia compressiva mais comum do membro superior, causada pela compressão direta sobre o nervo mediano no interior do canal cárpico.Os resultados deste estudo mostram em cada um dos grupos, após a intervenção, uma melhoria estatisticamente significativa da sintomatologia no G-AFN (p=0,02) e no GTRN/ EAA (p=0,004) e uma melhoria estatisticamente significativa do estado funcional no G-AFN (p=0,022). Verificamos também em cada um dos grupos, após a intervenção, uma melhoria estatisticamente significativa na “Força de preensão” (p=0,005), na “Pinça polegar/dedo indicador” (p=0,021), na “Pinça polegar/dedo médio” (p=0,026) e “Pinça polegar/dedo anular” (p=0,026) no G-AFN, e uma melhoria estatisticamente significativa na “Pinça polegar/indicador” (p=0,016), na “Pinça polegar/dedo médio” (p=0,035), na “Pinça polegar/dedo anular” (p=0,010), na “Pinça trípode” (p=0,005) e na “Pinça lateral” (p=0,051) no G-TRN/EAA. Após a intervenção, não verificamos diferenças estatisticamente significativas nos valores das escalas de gravidade de sintomas (p=0,853) e de estado funcional (p=0,148) entre os grupos, mas diferenças estatisticamente significativas nos valores dos testes neurofisiológicos (p=0,047) e força de preensão da mão (p=0,005). Do estudo, concluímos que a utilização da intervenção articular/fascial/neural (AFN) e a intervenção com tala de repouso noturna e exercícios de auto alongamento (TRN/EAA), beneficia os indivíduos com SCC não severa, como nos casos incipientes, ligeiros ou moderados. Os indivíduos com esta condição clínica apresentam sintomatologia caraterística de dor, parestesia, especialmente noturna e disfunção muscular da mão. Tais manifestações originam perda funcional com implicações nas áreas de desempenho ocupacional, nomeadamente, nas atividades da vida diária, produtivas e de lazer. O tratamento conservador na SCC não severa, como nos casos incipientes, ligeiros e moderados, apesar de controverso, é recomendado. O tema suscita o nosso interesse, razão pela qual nos propomos realizar um estudo experimental em indivíduos com o diagnóstico clínico de SCC não severa e aplicar num grupo a intervenção articular, fascial e neural (AFN) e noutro grupo a intervenção com tala de repouso noturna e exercícios de auto alongamento (TRN/EAA). O estudo tem como principais objetivos, por um lado, verificar o impacto das intervenções em cada um dos grupos e, por outro lado, comparar o seu impacto entre os grupos, no que respeita à gravidade de sintomas, ao estado funcional, à força de preensão da mão e força de pinças finas. Fomos também comparar os resultados dos testes neurofisiológicos (Velocidade de Condução Motora) antes e depois da intervenção AFN e da intervenção com TRN/EAA, e averiguar o seu impacto nos valores da latência motora distal e da velocidade de condução sensitiva, entre os grupos. Identificamos também quais as variáveis sócio demográficas e as que caraterizam a patologia que estão relacionadas com o problema em estudo e com os valores obtidos com as escalas do Boston Carpal Tunnel Questionnaire (BCTQ), no grupo articular, fascial e neural (G-AFN) e no grupo com tala de repouso noturna e exercícios de auto alongamento (G-TRN/EAA). Para a concretização do estudo, recorremos a uma amostra de 23 indivíduos de ambos os sexos do Hospital Curry Cabral, Empresa Pública Empresarial -Centro Hospitalar de Lisboa Central (HCC, EPE -CHLC).

Relationship of PON1 192 and 55 gene polymorphisms to calcific valvular aortic stenosis

Introduction and Objectives - Paraoxonases may exert anti-atherogenic action by reducing lipid peroxidation. Previous studies examined associations between polymorphisms in the paraoxonase 1 (PON1) gene and development of coronary artery disease (CAD), with inconsistent results. Given the similarities in clinical and pathophysiological risk factors of CAD and calcific aortic valve stenosis (CAVS), we postulated a link between PON1 alleles and CAVS progression. Methods - We investigated the association between PON1 55 and 192 single nucleotide polymorphisms (SNPs), their enzyme activity, and CAVS progression assessed by aortic valve area and transvalvular peak velocity in 67 consecutive patients with moderate CAVS and 251 healthy controls. Results - PON1 paraoxonase activity was higher in CAVS patients (P<0.001). The PON1 genotype Q192R SNP (P=0.03) and variant allele (R192) (P=0.01) frequencies differed between CAVS patients and controls. Significant association existed between PON1 enzyme activity, phenotypic effects of PON1 192 genotype polymorphisms, and CAVS progression, but not between PON1 55 and high-density lipoprotein (P=0.44) or low-density lipoprotein cholesterol (P=0.12), between 192 genotype and high-density lipoprotein (P=0.24) or low-density lipoprotein cholesterol (P=0.52). Conclusion - The PON1 genotype Q192R SNP has an important effect on CAVS disease progression. This study helps outline a genotype-phenotype relationship for PON1 in this unique population.

Genotoxic effects in occupational exposure to formaldehyde: A study in anatomy and pathology laboratories and formaldehyde-resins production

Background - According to the Report on Carcinogens, formaldehyde ranks 25th in the overall U.S. chemical production, with more than 5 million tons produced each year. Given its economic importance and widespread use, many people are exposed to formaldehyde environmentally and/or occupationally. Presently, the International Agency for Research on Cancer classifies formaldehyde as carcinogenic to humans (Group 1), based on sufficient evidence in humans and in experimental animals. Manyfold in vitro studies clearly indicated that formaldehyde can induce genotoxic effects in proliferating cultured mammalian cells. Furthermore, some in vivo studies have found changes in epithelial cells and in peripheral blood lymphocytes related to formaldehyde exposure. Methods - A study was carried out in Portugal, using 80 workers occupationally exposed to formaldehyde vapours: 30 workers from formaldehyde and formaldehyde-based resins production factory and 50 from 10 pathology and anatomy laboratories. A control group of 85 non-exposed subjects was considered. Exposure assessment was performed by applying simultaneously two techniques of air monitoring: NIOSH Method 2541 and Photo Ionization Detection equipment with simultaneously video recording. Evaluation of genotoxic effects was performed by application of micronucleus test in exfoliated epithelial cells from buccal mucosa and peripheral blood lymphocytes. Results - Time-weighted average concentrations not exceeded the reference value (0.75 ppm) in the two occupational settings studied. Ceiling concentrations, on the other hand, were higher than reference value (0.3 ppm) in both. The frequency of micronucleus in peripheral blood lymphocytes and in epithelial cells was significantly higher in both exposed groups than in the control group (p < 0.001). Moreover, the frequency of micronucleus in peripheral blood lymphocytes was significantly higher in the laboratories group than in the factory workers (p < 0.05). A moderate positive correlation was found between duration of occupational exposure to formaldehyde (years of exposure) and micronucleus frequency in peripheral blood lymphocytes (r = 0.401; p < 0.001) and in epithelial cells (r = 0.209; p < 0.01). Conclusions - The population studied is exposed to high peak concentrations of formaldehyde with a long-term exposure. These two aspects, cumulatively, can be the cause of the observed genotoxic endpoint effects. The association of these cytogenetic effects with formaldehyde exposure gives important information to risk assessment process and may also be used to assess health risks for exposed workers.

Familial amyloid polyneuropathy (FAP): clinical features, pathophysiology and treatment

In the literature, concepts of “polyneuropathy”, “peripheral neuropathy” and “neuropathy” are often mistakenly used as synonyms. Polyneuropathy is a specific term that refers to a relatively homogenous process that affects multiple peripheral nerves. Most of these tend to present as symmetric polyneuropathies that first manifest in the distal portions of the affected nerves. Many of these distal symmetric polyneuropathies are due to toxic-metabolic causes such as alcohol abuse and diabetes mellitus. Other distal symmetric polyneuropathies may result from an overproduction of substances that result in nerve pathology such as is observed in anti-MAG neuropathy and monoclonal gammopathy of undetermined significance. Other “overproduction” disorders are hereditary such as noted in the Portuguese type of familial amyloid polyneuropathy (FAP). FAP is a manifestation of a group of hereditary amyloidoses; an autosomal dominant, multisystemic disorder wherein the mutant amyloid precursor, transthyretin, is produced in excess primarily by the liver. The liver accounts for approximately 98% of all transthyretin production. FAP is confirmed by detecting a transthyretin variant with a methionine for valine substitution at position 30 [TTR (Met30)]. Familial Amyloidotic Polyneuropathy (FAP) – Portuguese type was first described by a Portuguese neurologist, Corino de Andrade in 1939 and published in 1951. Most persons with this disorder are descended from Portuguese sailors who sired offspring in various locations, primarily in Sweden, Japan and Mallorca. Their descendants emigrated worldwide such that this disorder has been reported in other countries as well. More than 2000 symptomatic cases have been reported in Portugal. FAP progresses rapidly with an average time course from symptom onset to multi-organ involvement and death between ten and twenty years. Treatments directed at removing this aberrant protein such as plasmapheresis and immunoadsorption proved to be unsuccessful. Liver transplantation has been the only effective solution as evidenced by almost 2000 liver transplants performed worldwide. A therapy for FAP with a novel agent, “Tafamidis” has shown some promise in ongoing phase III clinical trials. It is well recognized that regular physical activity of moderate intensity has a positive effect on physical fitness as gauged by body composition, aerobic capacity, muscular strength and endurance and flexibility. Physical fitness has been reported to result in the reduction of symptoms and lesser impairment when performing activities of daily living. Exercise has been advocated as part of a comprehensive approach to the treatment of chronic diseases. Therefore, this chapter concludes with a discussion of the role of exercise training on FAP.