932 resultados para tire rolling circumference
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Introduction: Highly Active Antiretroviral Therapy (HAART) has improved and extended the lives of thousands of people living with HIV/AIDS around the world. However, this treatment can lead to the development of adverse reactions such as lipoatrophy/lipohypertrophy syndrome (LLS) and its associated risks. Objective: This study was designed to assess the prevalence of self-reported lipodystrophy and nutritional status by anthropometric measurements in patients with HIV/AIDS. Methods: An observational study of 227 adult patients in the Secondary Immunodeficiencies Outpatient Department of Dermatology, Hospital das Clínicas, Faculty of Medicine, University of São Paulo (3002 ADEE-HCFMUSP). The sample was divided into three groups; Group 1 = 92 patients on HAART and with self-reported lipodystrophy, Group 2 = 70 patients on HAART without self-reported lipodystrophy and Group 3 = 65 patients not taking HAART. The nutritional status of individuals in the study sample was determined by body mass index (BMI) and percentage of body fat (% BF). The cardiovascular risk and diseases associated with abdominal obesity were determined by waist/hip ratio (WHR) and waist circumference (WC). Results: The prevalence of self-reported lipoatrophy/lipohypertrophy syndrome was 33% among women and 59% among men. Anthropometry showed depletion of fat mass in the evaluation of the triceps (TSF) in the treatment groups with HAART and was statistically independent of gender; for men p = 0.001, and for women p = 0.007. Similar results were found in the measurement of skin folds of the upper and lower body (p = 0.001 and p = 0.003 respectively). In assessing the nutritional status of groups by BMI and % BF, excess weight and body fat were more prevalent among women compared to men (p = 0.726). The WHR and WC revealed risks for cardiovascular and other diseases associated with abdominal obesity for women on HAART and with self-reported LLS (p = 0.005) and (p = 0.011). Conclusions: Anthropometric measurements were useful in the confirmation of the prevalence of LLS. BMI alone does not appear to be a good parameter for assessing the nutritional status of HIV-infected patients on HAART and with LLS. Other anthropometric measurements are needed to evaluate patients with the lipoatrophy/lipohypertrophy syndrome.
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OBJECTIVE:Endograft mural thrombus has been associated with stent graft or limb thrombosis after endovascular aneurysm repair (EVAR). This study aimed to identify clinical and morphologic determinants of endograft mural thrombus accumulation and its influence on thromboembolic events after EVAR. METHODS: A prospectively maintained database of patients treated by EVAR at a tertiary institution from 2000 to 2012 was analyzed. Patients treated for degenerative infrarenal abdominal aortic aneurysms and with available imaging for thrombus analysis were considered. All measurements were performed on three-dimensional center-lumen line computed tomography angiography (CTA) reconstructions. Patients with thrombus accumulation within the endograft's main body with a thickness >2 mm and an extension >25% of the main body's circumference were included in the study group and compared with a control group that included all remaining patients. Clinical and morphologic variables were assessed for association with significant thrombus accumulation within the endograft's main body by multivariate regression analysis. Estimates for freedom from thromboembolic events were obtained by Kaplan-Meier plots. RESULTS: Sixty-eight patients (16.4%) presented with endograft mural thrombus. Median follow-up time was 3.54 years (interquartile range, 1.99-5.47 years). In-graft mural thrombus was identified on 30-day CTA in 22 patients (32.4% of the study group), on 6-month CTA in 8 patients (11.8%), and on 1-year CTA in 17 patients (25%). Intraprosthetic thrombus progressively accumulated during the study period in 40 patients of the study group (55.8%). Overall, 17 patients (4.1%) presented with endograft or limb occlusions, 3 (4.4%) in the thrombus group and 14 (4.1%) in the control group (P = .89). Thirty-one patients (7.5%) received an aortouni-iliac (AUI) endograft. Two endograft occlusions were identified among AUI devices (6.5%; overall, 0.5%). None of these patients showed thrombotic deposits in the main body, nor were any outflow abnormalities identified on the immediately preceding CTA. Estimated freedom from thromboembolic events at 5 years was 95% in both groups (P = .97). Endograft thrombus accumulation was associated with >25% proximal aneurysm neck thrombus coverage at baseline (odds ratio [OR], 1.9; 95% confidence interval [CI], 1.1-3.3), neck length ≤ 15 mm (OR, 2.4; 95% CI, 1.3-4.2), proximal neck diameter ≥ 30 mm (OR, 2.4; 95% CI, 1.3-4.6), AUI (OR, 2.2; 95% CI, 1.8-5.5), or polyester-covered stent grafts (OR, 4.0; 95% CI, 2.2-7.3) and with main component "barrel-like" configuration (OR, 6.9; 95% CI, 1.7-28.3). CONCLUSIONS: Mural thrombus formation within the main body of the endograft is related to different endograft configurations, main body geometry, and device fabric but appears to have no association with the occurrence of thromboembolic events over time.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics
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RESUMO: Conclusão - Este estudo sugere que mulheres grávidas beneficiam da prática rotineira de 30 min de relaxamento perante a eminência de um acontecimento indutor de stress. O benefício será tanto psicológico como fisiológico e será mais marcado de manhã do que de tarde. As mulheres com maior tendência ansiosa, tipicamente as mais jovens e com menos idade gestacional, serão as que mais beneficiam. Entre os tipos de intervenção experimentados, todos eles não dispendiosos, a audição de música foi globalmente o mais eficaz para o propósito pretendido. A variação do cortisol e a variação da testosterona estão altamente correlacionadas, e este efeito poderá ser explorado em futuras intervenções relaxantes. Programas curtos de relaxamento poderão conduzir a benefícios para o bem-estar psicológico e para a saúde da grávida, com benefícios adicionais no desfecho da gravidez. O rácio digital 2D:4D do recém-nascido apresenta características sexualmente dimórficas, sendo mais baixo em rapazes que em raparigas, confirmando a influência dos androgénios pré-natais, mas há grande sobreposição entre os sexos pelo que, isoladamente, não pode ser utilizado como marcador de risco. No entanto, se associado a outros marcadores biológicos, como o peso ao nascer e a circunferência cerebral, entre outros, poderá ser um parâmetro a valorizar desde cedo, possivelmente no acompanhamento pediátrico. Nas raparigas, o RD da mãe e a testosterona no LA explicam uma proporção significativa do seu 2D:4D. Em ambos os sexos, o rácio 2D:4D aumenta após o nascimento e o dimorfismo sexual observado com base em amostras de crianças com mais de dois anos de idade, é afectado pela testosterona pós-natal, especialmente no que se refere à mão direita.----------ABSTRACT: Conclusions - This study suggests that pregnant women would benefit from the routine practice of 30min relaxation when at the imminence of a stressful event. The benefit would be both psychological and physiological and would be more pronounced in the morning than in the afternoon. Women tending to be more anxious, typically younger and at a lower gestational age, are the ones that benefit the most. Among the interventions investigated, all being non-expensive and easy to implement, listening to relaxing music was globally the most efficient for the benefit intended. The variation of cortisol and the variation of testosterone are significantly correlated, an association that might be used in future relaxation interventions. It is feasible to conceive short relaxation programs aimed at benefiting psychological well-being and health in pregnancy, with additional benefits for pregnancy outcome. The digital ratio 2D:4D is sexually dimorphic, being lower in males than in females, confirming the influence of pre-natal androgens. There is however large overlap between sexes, rendering the 2D:4D a risk marker not to be used in isolation but rather in association with other markers, like for instance the weight at birth and the head circumference, wherein it may be a relevant parameter for pediatric follow-up. In newborn females, a significant amount of variability in 2D:4D is accounted for by their mother’s digital ratio and AF testosterone. In both sexes, the 2D:4D ratio increases following birth and sexual dimorphism,as assessed from samples of subjects with more than 2 years of age, is affected by post-natal testosterone, especially in what concerns the right hand.
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RESUMO - Introdução: A literatura aponta que a gravidez é um período do ciclo reprodutivo associado com o excesso de peso, que se tem tornado um problema de saúde pública em ascensão. Na verdade, evidências sugerem que o excessivo peso pré-gestacional e o ganho ponderal excessivo estão associados a um peso elevado do RN. Objetivos: Relacionar o IMC antes da conceção e o ganho ponderal durante a gestação com o PN do RN. Métodos: Foi realizado um estudo epidemiológico, analítico, observacional e transversal, com uma amostra de cento e três mães e respetivos RNs, de termo, saudáveis e de gravidez única, da Unidade de Obstetrícia do Hospital Beatriz Ângelo. Estas foram recrutadas entre novembro de 2012 e março de 2013 inclusive. Para tal, foram recolhidos dados clínicos e outras informações relativas à gravidez e parto, nomeadamente o PN, através do sistema informático. Resultados: Após a análise dos resultados, constatou-se que mães com IMC superior a 25 antes da gravidez apresentam ganho ponderal durante a gravidez acima dos valores recomendados (47,2%). A prevalência de macrossomia e baixo peso ao nascer também foi maior em mães com excesso de peso (p=0,021), tal como de PIG e GIG (p=0,004). Observando a influência do ganho ponderal verificou-se que 9,5% (n=4) das mães com ganho ponderal excessivo tiveram RN com elevado peso ao nascer, enquanto 14,3% (n=4) das mães com ganho ponderal abaixo do recomendado tiveram RN com baixo peso ao nascer (p=0,018). Verificou-se também que o tempo de gestação é maior em mães com ganho ponderal acima do recomendado (p=0,024), e que este fator está positivamente associado com o PN (r=0,218; p=0,029), comprimento (r=0,221; p=0,027) e PC (r=0,249; p=0,012) do RN. No que se refere às correlações, encontrou-se uma correlação positiva moderada entre os fatores maternos (peso antes de engravidar; IMC pré-gestacional; e ganho ponderal) e o PN. Discussão/Conclusão: Desta forma, podemos concluir que tanto o excesso de peso pré-gestacional como o ganho de peso inadequado durante a gestação têm implicações diretas no peso do recém-nascido, nomeadamente aumentando o risco de macrossomia fetal.
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Economics from the NOVA – School of Business and Economics
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Endemic pemphigus foliaceus, and long-term corticotherapy may affect serum lipid levels. The aim of this study was to compare serum lipids of pemphigus foliaceus patients on glucocorticoid therapy to a healthy control group. Fifteen patients receiving prednisone (0.33 ± 0.22mg/kg) for at least 12 months and 15 controls were submitted to 48-h food intake records, anthropometry, and biochemical measurements. Data were compared by chi2, Mann-Whitney and Student "t" tests. The groups were matched for gender, age, weight, body mass index, arm circumference and triceps skin fold. No differences were observed in relation to energy, fat, protein and carbohydrate daily intakes, total cholesterol, HDL, LDL, uric acid, and serum creatinine levels. Pemphigus foliaceus patients had higher triglyceride [159 (64-371) vs. 100 (45-133) mg/dl], VLDL [32 (13-74) vs. 20 (9-114) mg/dl] and ESR [44 (9-87) vs. 7 (1-30) mm/h] levels than controls, probably due to metabolic effects of inflammatory disease and corticotherapy.
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RESUMO: Ao longo das últimas décadas a redistribuição etária da população mundial tem vindo a apresentar um aumento do número de pessoas com 65 ou mais anos, integrando um grupo populacional comummente designado por população idosa. Importa aprofundar mecanismos fisiológicos que conduzem ao envelhecimento e de que forma podem condicionar não só aspetos clínicos, como também nutricionais, entre outros, com a perspetiva da sua origem no aparecimento de doenças crónicas. Com esse enfoque, a desnutrição na pessoa idosa é hoje considerada pela European Nutrition for Health Alliance(ENHA) um problema de saúde pública. Está descrito que a sua prevalência ronda os 60% a nível de instituições hospitalares, 40% em unidades residenciais e 5 a 10% na pessoa idosa a residir em domicílio próprio ou de familiares, e na sua maioria permanece por diagnosticar e tratar. Assim, foi objetivo deste estudo caracterizar e estimar a prevalência da desnutrição e do risco de desnutrição na pessoa idosa, nas primeiras 72 horas de admissão hospitalar. Aplicou-se um estudo observacional, analítico, transversal, quantitativo e correlacional, cujos dados foram recolhidos por entrevista ao próprio e por observação. O estudo desenvolveu-se em duas vertentes de investigação, uma focada na caracterização da desnutrição em pessoas idosas institucionalizadas em hospitais portugueses da zona centro e sul do Continente e Madeira, nos períodos de julho/agosto de 2009, abril/junho de 2010, maio/julho de 2011, através do MNA®. A outra, uma avaliação nutricional detalhada, efetuada no Centro Hospitalar de Lisboa Central – Hospital de Santa Marta, EPE, entre o início de janeiro de 2009 e o fim de janeiro de 2010, sendo a amostra recrutada de entre os idosos de ambos os sexos, internados. Foram estudados dados sociodemográficos, de saúde e feita uma avaliação nutricional extensa. A avaliação nutricional constou de colheita de parâmetros laboratoriais (hematológicos e bioquímicos) e antropométricos (índice de massa corporal (IMC), prega cutânea tricipital(PCT), prega cutânea subescapular (PCSE), perímetro braquial (PB), adequação do perímetro braquial (APB), área muscular braquial (AMB) e perímetro Geminal (PG), análise da composição corporal (Massa Gorda Corporal (MGC), Massa Isenta de Gordura (MIG)),caracterização de um dia alimentar tipo e questionário Mini Nutritional Assessment Long Form®– MNA LF®. Dos dados obtidos em hospitais portugueses, destaca-se que dos 402 idosos avaliados, 53% eram do sexo masculino, tinham uma idade média de 75,8 + 6,52 (65 – 100) e segundo o MNA® 57,5% encontravam-se Desnutridos ou em Risco de Desnutrição.Na amostra, dos dados obtidos, a nível sociodemográfico salienta-se que 50% dos doentes eram do sexo masculino, a idade média rondava os 75,5 + 7,22 (65 – 100) anos, 55% eram naturais de Lisboa e 80% residiam em Lisboa e Vale do Tejo, 38% não tiveram estudos formais e 43% fizeram-no apenas até ao 4º ano de escolaridade. Em relação aos dados de saúde, a maioria dos doentes foi admitida através do Serviço de Urgência do Centro Hospitalar de Lisboa Central – Hospital de São José e foram internados no Serviço de Medicina (38%) e no Serviço de Cardiologia (30%), por patologia médica (38%) e patologia do sistema circulatório (56%). Nos hábitos de vida, quanto à mobilidade, um terço dos doentes estavam acamados e os restantes deambulavam ou tinham uma mobilidade normal, 74% não apresentaram hábitos etanólicos regulares, 19% apresentavam um consumo elevado (> 30g de etanol/dia); 95% dos doentes não apresentavam hábitos tabágicos. Relativamente à caracterização nutricional, os valores médios encontrados em relação aos parâmetros laboratoriais revelaram-se inferiores aos valores padrão para a idade e sexo e eram inferiores no sexo feminino. Na caracterização antropométrica verificaram-se os seguintes achados: o cálculo do IMC mostrou-se pouco sensível na identificação de doentes desnutridos; a PCT e a PCSE revelaram valores de massa gorda dentro do intervalo considerado normal;segundo o PB, 88% não apresentavam valor indicativo de desnutrição e 8% estavam desnutridos; a APB identificou 50% de doentes desnutridos; a AMB, revelou que 97% dos homens e 95% das mulheres apresentavam deficit da massa magra e segundo o PG, 18% apresentavam um valor inferior a 31cm descritor de desnutrição. Na análise da composição corporal verificou-se que ambos os sexos apresentavam uma percentagem de MGC classificada como demasiado alta e que esta era superior nas mulheres em relação aos homens. Ao analisar a ingestão nutricional verificou-se que esta era inferior às Dietary Reference Intakes (DRIs) para a ingestão hídrica (p=0,00), energética (p=0,00), proteica (p=0,00), lipídica (p=0,01), MUFA (p=0,00), PUFA (p=0,00), e glícidos (p=0,00), fibra (p=0,02), potássio (p=0,00), cálcio (p=0,00), magnésio (p=0,00), fósforo (p=0,00), zinco (p=0,00), vitamina D (p=0,00), vitamina E (p=0,00) e folato (p=0,00). No que diz respeito ao MNA®, a sua aplicação permitiu identificar 62% de situações de risco nutricional ou de desnutrição já instalada. Valores de MNA® indicativos de desnutrição ou risco estavam associados a níveis de escolaridade mais baixos (r=0,32; p=0,00). Verificou-se correlação entre o MNA® e a PCT (r=0,30;p=0,00), PCSE (r=0,19;p=0,03) e PG (r=0,27;p=0,00). Na análise da amostra por sexo e escalão etário, apenas se distinguiram as mulheres mais velhas, que apresentaram situação de IMC indicador de risco de desnutrição (IMC <23,5 + 2,9, (r=0,42;p=0,02)), e de valores médios de PB de 25,6+3,84cm (r=0,42;p=0,01), em situações de menor mobilidade caraterizados pelo MNA®. Os homens maisvelhos apresentaram correlação entre o MNA® e PCSE (r=0,41;p=0,02), APMB (r=0,57;p=0,00)e PG (r=0,55;p=0,00), e as mulheres mais velhas apenas com a PCT (r=0,39;p=0,02). A análise multivariada do MNA® em função do sexo e do escalão etário, revelou que estes são independentes. Os homens apresentaram valores médios de MNA® superiores às mulheres e à medida que a idade aumenta, os valores de MNA® em ambos os sexos diminuem, sendo indicativos de risco de desnutrição. Consideramos que, tendo em conta a natureza e objetivos do presente estudo, foi possível caracterizar e estimar a prevalência da desnutrição e do risco de desnutrição em pessoas idosas nas primeiras 72 horas de admissão hospitalar. Os resultados obtidos sinalizam a sua elevada prevalência e alertam para a necessidade de procedimentos protocolados de avaliação e intervenção nutricional da população idosa na admissão hospitalar. Para este efeito a aplicação do MNA® provou a sua aplicabilidade, assim como a medição e cálculo da AMB, que poderão ser muito precocemente aplicados e contribuir para potenciar melhorias do estado de saúde e diminuir o tempo de internamento, nomeadamente de pessoas idosas. Em relação ao padrão alimentar, este estudo contribuiu para uma chamada de atenção dos profissionais de saúde que a população idosa pode apresentar carências nutricionais na admissão, e que estas se não forem devidamente sinalizadas e colmatadas tendem a agravar-se durante o internamento podendo contribuir para o aumento da morbilidade.-------------ABSTRACT:Over the last decades the age redistribution group of the population worldwide has been presenting an increasing number of people aged 65 years or more, incorporating a population group commonly referred to as the elderly population. It´s important to further analyze the physiological mechanisms that lead to aging and how they might influence not only clinical aspects, but also nutritional, among others, with the perspective of their origin in the onset of chronic diseases. With this approach, malnutrition in the elderly is now considered by the European Nutrition for Health Alliance (ENHA) a public health problem. It is reported that its prevalence is around 60% at the level of hospital units, 40% in residential units and 5 to 10% in the elderly living in their own home or family's, and mostly remains to diagnose and treat. The aim of this study was to characterize and estimate the prevalence of malnutrition and risk of malnutrition in the elderly, in the first 72 hours of hospital admission. We applied an observational, analytical, cross-sectional and correlacional quantitative type of study and data were collected by interview and observation itself. The study was developed in two lines of research: one focused on the characterization of malnutrition in elderly institutionalized in Portuguese hospitals, in the central and southern mainland and Madeira, in the periods between July - August 2009, April - June 2010, May - July 2011, through the MNA®; and the other: a detailed nutritional assessment, conducted in Hospital Lisbon Center - Hospital de Santa Marta, EPE, between early January 2009 and late January 2010, and the sample was recruited from among the elderly of both sexes at hospital admission. We studied intensively sociodemographic, health and nutritional assessment done extensive. Nutritional evaluation consisted of harvesting different parameters: hematological, biochemical and anthropometric (body mass index (BMI), triceps skinfold (TSF), sub-scapular skinfold (SSF), arm circumference (AC), arm muscle area (AMA), geminal perimeter (GP), analysis of body composition (Fat Mass (FM), Fat Free Mass (FFM)), characterization of a daily food type and Mini Nutritional Assessment Long Form® questionnaire - MNA LF®. Form the data obtained in Portuguese hospitals, it is noteworthy that of the 402 patients included, 53% were male, had a mean age of 75,8 + 6,52 (65 - 100) and, according to the MNA®, 57,5% were malnourished or at risk of malnutrition. In the sample, from the sociodemographic data obtained, we saw that 50% of patients were male, the average age was around 75,5 + 7,22 years (65-100), 55% were from Lisbon and 80 %lived in Lisbon, 38% had no formal education and 43% did so only until the 4th grade. Regarding health data, the majorities of patients were admitted through the ER of Hospital Lisbon Center - S. José Hospital - and were admitted to the Medicine Unit (38%) and to the Cardiology Unit (30%), by medical pathology (38%) and circulatory system disease (56%). In regard to lifestyle, and considering mobility, one third of patients were bedridden and the rest were ambulating or had a normal mobility. 74% had no regular ethanol habits, 19% had a high intake (> 30 g ethanol / day); 95% of the patients had no smoking habits. Regarding nutritional assessment, the mean values for laboratory parameters proved inferior to standard values for age and sex and were lower in females. In anthropometric assessment these were the findings: BMI calculation showed to be scarcely sensitive in the identification of undernourished patients; the TSF and SSF revealed values of fat mass within the normal range; in AC, 88% did not have an indicative value of malnutrition and 8% were malnourished; in AMA, 97% of men and 95% women had a deficit of lean mass and in GP, 18% had a value of less than the 31cm malnutrition descriptor. In body composition analysis found that both sexes showed a percentage of FM ranked too high and this was higher in women compared to men. By analyzing the nutritional intake was found that this was less than the Dietary Reference Intakes (DRIs) for water intake (p=0,00), energy (p=0,00), protein (p=0,00), lipid (p=0,01), MUFA (p=0,00), PUFA (p=0,00), carbohydrates (p=0,00), fiber (p=0,02), potassium (p=0,00), calcium (p=0,00), magnesium (p=0,00), phosphorus (p=0,00), zinc (p=0,00), vitamin D (p=0,00), vitamin E (p=0,00) and folate (p=0,00). Regarding MNA®, its application identified 62% of cases of nutritional risk or malnutrition already installed. MNA® values indicative of malnutrition or risk were associated with lower levels of education (r=0,32; p=0,00). There was a correlation between the MNA ® and TSF (r =0,30, p = 0,00), SFF (r = 0,19, p = 0,03) and GP (r=0,27, p = 0,00). In the analysis of the sample by gender and age group, the highlight was in older women who had BMI status indicator of malnutrition risk (BMI <23,5 + 2,9 (r=0,42;p=0,02)) and mean values of AC 25,6 +3,84cm (r=0,42; p=0,01), in situations characterized by low mobility MNA®. Older men showed a correlation between the MNA® and SFF (r = 0,41; p = 0,02), AMA (r = 0,57; p = 0,00) and GP (r=0,55;p=0,00), and in older women only TSF showed a correlation(r = 0,39; p =0,02). Multivariate analysis of the MNA® by gender and age group, revealed that they are independent. The men had MNA® mean superior to women, and as the age increases, the values of MNA® in both sexes declined, being indicative of risk of malnutrition. We believe that, given the nature and objectives of the present study, it allowed us to characterize and estimate the prevalence of risk of malnutrition and malnutrition in older people during the first 72 hours of hospital admission. The results indicate a high prevalence and point to the need for protocol procedures of nutritional assessment and intervention in the elderly population at hospital admission. For this purpose the application of MNA® has proved its applicability, as well as measuring and calculating AMA, which may be applied in early stages thus contributing to enhance health state improvements and to shorten the time of hospitalization, particularly in elderly people. In relation to dietary pattern, this study contributed to call of attention from health professionals that the elderly may have nutritional deficiencies on admission, and that these are not properly marked and addressed tend to worsen during hospitalization may contribute to increased morbidity.
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Shape memory alloys are characterized by the ability of recovering their initial shape after being deformed and by superelasticity. Since the discovery of these alloys, a new field of interest emerged not only for the scientific community but also to many industries. However, these alloys present poor machinability which constitute a constrain in the design of complex components for new applications. Thus, the demand for joining techniques able to join these alloys without compromising their properties became of great importance to enlarge the complexity of existing applications. Literature shows that these alloys are joined mainly using laser welding. In the present study, similar NiTi butt joints, were produced using TIG welding. The welds were performed in 1.5 mm thick plates across the rolling direction. A special fixture and gas assist device was designed and manufactured. Also a robot arm was adapted to accommodate the welding torch to assure the repeatability of the welding parameters. Welds were successfully achieved without macroscopic defects, such as pores and distortions. Very superficial oxidation was seen on the top surface due to insufficient shielding gas flow on the weld face. The welded joints were mechanically tested and structurally characterized. Testing methods were used to evaluate macro and microstructure, as well as the phase transformation temperatures, the mechanical single and cyclic behaviour and the shape recovery ability. Differential Scanning Calorimetry (DSC), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), microhardness measurements were techniques also used to evaluate the welded joints. A depletion in Ni in the fusion zone was seen, as well as a shift in Ms temperature. For strain values of 4% the accumulated irrecoverable strain was of about 30% and increased with the strain imposed during cycling. Nevertheless, a complete recovery of initial shape was observed when testing the shape memory effect on a dedicated device that introduces a deformation of 6.7%. That is, the welding procedure does not remove the ability of the specimens to recover their initial shape.
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Most of today’s systems, especially when related to the Web or to multi-agent systems, are not standalone or independent, but are part of a greater ecosystem, where they need to interact with other entities, react to complex changes in the environment, and act both over its own knowledge base and on the external environment itself. Moreover, these systems are clearly not static, but are constantly evolving due to the execution of self updates or external actions. Whenever actions and updates are possible, the need to ensure properties regarding the outcome of performing such actions emerges. Originally purposed in the context of databases, transactions solve this problem by guaranteeing atomicity, consistency, isolation and durability of a special set of actions. However, current transaction solutions fail to guarantee such properties in dynamic environments, since they cannot combine transaction execution with reactive features, or with the execution of actions over domains that the system does not completely control (thus making rolling back a non-viable proposition). In this thesis, we investigate what and how transaction properties can be ensured over these dynamic environments. To achieve this goal, we provide logic-based solutions, based on Transaction Logic, to precisely model and execute transactions in such environments, and where knowledge bases can be defined by arbitrary logic theories.
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This paper studies the effects of monetary policy on mutual fund risk taking using a sample of Portuguese fixed-income mutual funds in the 2000-2012 period. Firstly I estimate time-varying measures of risk exposure (betas) for the individual funds, for the benchmark portfolio, as well as for a representative equally-weighted portfolio, through 24-month rolling regressions of a two-factor model with two systematic risk factors: interest rate risk (TERM) and default risk (DEF). Next, in the second phase, using the estimated betas, I try to understand what portion of the risk exposure is in excess of the benchmark (active risk) and how it relates to monetary policy proxies (one-month rate, Taylor residual, real rate and first principal component of a cross-section of government yields and rates). Using this methodology, I provide empirical evidence that Portuguese fixed-income mutual funds respond to accommodative monetary policy by significantly increasing exposure, in excess of their benchmarks, to default risk rate and slightly to interest risk rate as well. I also find that the increase in funds’ risk exposure to gain a boost in return (search-for-yield) is more pronounced following the 2007-2009 global financial crisis, indicating that the current historic low interest rates may incentivize excessive risk taking. My results suggest that monetary policy affects the risk appetite of non-bank financial intermediaries.
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Introduction Even with current highly active antiretroviral therapy, individuals with AIDS continue to exhibit important nutritional deficits and reduced levels of albumin and hemoglobin, which may be directly related to their cluster of differentiation 4 (CD4) cell counts. The aim of this study was to characterize the nutritional status of individuals with human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) and relate the findings to the albumin level, hemoglobin level and CD4 cell count. Methods Patients over 20 years of age with AIDS who were hospitalized in a university hospital and were receiving antiretroviral therapy were studied with regard to clinical, anthropometric, biochemical and sociodemographic characteristics. Body mass index, percentage of weight loss, arm circumference, triceps skinfold and arm muscle circumference were analyzed. Data on albumin, hemoglobin, hematocrit and CD4 cell count were obtained from patient charts. Statistical analysis was performed using Fisher's exact test, Student's t-test for independent variables and the Mann-Whitney U-test. The level of significance was set to 0.05 (α = 5%). Statistical analysis was performed using Statistical Package for the Social Sciences (SPSS) 17.0 software for Windows. Results Of the 50 patients evaluated, 70% were male. The prevalence of malnutrition was higher when the definition was based on arm circumference and triceps skinfold measurement. The concentrations of all biochemical variables were significantly lower among patients with a body mass index of less than 18.5kg/m2. The CD4 cell count, albumin, hemoglobin and hematocrit anthropometric measures were directly related to each other. Conclusions These findings underscore the importance of nutritional follow-up for underweight patients with AIDS, as nutritional status proved to be related to important biochemical alterations.
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Introduction: Human T cell lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) can impact the independence and motricity of patients. The aims of this study were to estimate the effects of physiotherapy on the functionality of patients with HAM/TSP during the stable phase of the disease using proprioceptive neuromuscular facilitation (PNF) and to compare two methods of treatment delivery. Methods: Fourteen patients with human T cell lymphotropic virus type I (HTLV-I) were randomly allocated into two groups. In group I (seven patients), PNF was applied by the therapist, facilitating the functional activities of rolling, sitting and standing, walking and climbing and descending stairs. In group II (seven patients), PNF was self-administered using an elastic tube, and the same activities were facilitated. Experiments were conducted for 1h twice per week for 12 weeks. Low-back pain, a modified Ashworth scale, the functional independence measure (FIM) and the timed up and go test (TUG) were assessed before and after the interventions. Results: In the within-group evaluation, low-back pain was significantly reduced in both groups, the FIM improved in group II, and the results of the TUG improved in group I. In the inter-group analysis, only the tone was lower in group II than in group I. Conclusions: Both PNF protocols were effective in treating patients with HAM/TSP.
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RESUMO: A hipertensão arterial (HA) é uma patologia altamente prevalente, embora claramente subdiagnosticada, em doentes com síndrome de apneia obstrutiva do sono (SAOS). Estas duas patologias apresentam uma estreita relação e a monitorização ambulatória da pressão arterial (MAPA), por um período de 24 horas, parece ser o método mais preciso para o diagnóstico de hipertensão em doentes com SAOS. No entanto, esta ferramenta de diagnóstico para além de ser dispendiosa e envolver um número acrescido de meios técnicos e humanos, é mais morosa e, por conseguinte, não é utilizada por rotina no contexto do diagnóstico da SAOS. Por outro lado, apesar da aplicação de pressão positiva contínua nas vias aéreas (CPAP – Continous Positive Airway Pressure) ser considerada a terapêutica de eleição para os doentes com SAOS, o seu efeito no abaixamento da pressão arterial (PA) parece ser modesto, exigindo, por conseguinte, a implementação concomitante de terapêutica anti-hipertensora. Acontece que são escassos os dados relativos aos regimes de fármacos anti-hipertensores utilizados em doentes com SAOS e, acresce ainda que, as guidelines terapêuticas para o tratamento farmacológico da HA, neste grupo particular de doentes, permanecem, até ao momento, inexistentes. A utilização de modelos animais de hipóxia crónica intermitente (CIH), que mimetizam a HA observada em doentes com SAOS, revela-se extremamente importante, uma vez que se torna imperativo identificar fármacos que promovam um controle adequado da PA neste grupo de doentes. No entanto, estudos concebidos com o intuito de investigar o efeito anti-hipertensor dos fármacos neste modelo animal revelam-se insuficientes e, por outro lado, os escassos estudos que testaram fármacos anti-hipertensores neste modelo não foram desenhados para responder a questões de natureza farmacológica. Acresce ainda que se torna imprescindível garantir a escolha de um método para administração destes fármacos que seja não invasivo e que minimize o stress do animal. Embora a gavagem seja uma técnica indiscutivelmente eficaz e amplamente utilizada para a administração diária de fármacos a animais de laboratório, ela compreende uma sequência de procedimentos geradores de stress para os animais e, que podem por conseguinte, constituir um viés na interpretação dos resultados obtidos. O objectivo global da presente investigação translacional foi contribuir para a identificação de fármacos anti-hipertensores mais efectivos para o tratamento da HT nos indivíduos com SAOS e investigar mecanismos subjacentes aos efeitos sistémicos associadas à SAOS bem como a sua modulação por fármacos anti-hipertensores. Os objectivos específicos foram: em primeiro lugar,encontrar novos critérios, baseados nas medidas antropométricas, que permitam a identificação de doentes com suspeita de SAOS, que erroneamente se auto-classifiquem como nãohipertensos, e desta forma promover um uso mais criterioso do MAPA; em segundo lugar, investigar a existência de uma hipotética associação entre os esquemas de fármacos antihipertensores e o controle da PA (antes e após a adaptação de CPAP) em doentes com SAOS em terceiro lugar, avaliar a eficácia do carvedilol (CVD), um fármaco bloqueador β-adrenérgico não selectivo com actividade antagonista α1 intrínseca e propriedades anti-oxidantes num modelo animal de hipertensão induzida pela CIH; em quarto lugar, explorar os efeitos da CIH sobre o perfil farmacocinético do CVD; e, em quinto lugar, investigar um método alternativo à gavagem para a administração crónica de fármacos anti-hipertensores a animais de laboratório. Com este intuito, na primeira fase deste projecto, fizemos uso de uma amostra com um número apreciável de doentes com SAOS (n=369), que acorreram, pela primeira vez, à consulta de Patologia do Sono do CHLN e que foram submetidos a um estudo polissonográfico do sono, à MAPA e que preencheram um questionário que contemplava a obtenção de informação relativa ao perfil da medicação anti-hipertensora em curso. Numa segunda fase, utilizámos um modelo experimental de HT no rato induzida por um paradigma de CIH. Do nosso trabalho resultaram os seguintes resultados principais: em primeiro lugar, o índice de massa corporal (IMC) e o perímetro do pescoço (PP) foram identificados como preditores independentes de “auto-classificação errónea” da HA em doentes com suspeita de SAOS; em segundo lugar, não encontramos qualquer associação com significado estatístico entre os vários esquemas de fármacos anti-hipertensores bem como o número de fármacos incluídos nesse esquemas, e o controle da PA (antes e depois da adaptação do CPAP); em terceiro lugar, apesar das doses de 10, 30 e 50 mg/kg de carvedilol terem promovido uma redução significativa da frequência cardíaca, não foi observado qualquer decréscimo na PA no nosso modelo animal; em quarto lugar, as razões S/(R+S) dos enantiómeros do CVD nos animais expostos à CIH e a condições de normóxia revelaram-se diferentes; e, em quinto lugar, a administração oral voluntária mostrou ser um método eficaz para a administração diária controlada de fármacos anti-hipertensores e que é independente da manipulação e contenção do animal. Em conclusão, os resultados obtidos através do estudo clínico revelaram que o controle da PA, antes e após a adaptação do CPAP, em doentes com SAOS é independente, quer do esquema de fármacos anti-hipertensores, quer do número de fármacos incluídos num determinado esquema. Os nossos resultados salientam ainda a falta de validade da chamada self-reported hypertension e sugerem que em todos os doentes com suspeita de SAOS, com HA não diagnosticada e com um IMC e um PP acima de 27 kg/m2 e 39 cm, respectivamente, a confirmação do diagnóstico de HA deverá ser realizada através da MAPA, ao invés de outros métodos que com maior frequência são utilizados com este propósito. Os resultados obtidos no modelo animal de HA induzida pela CIH sugerem que o bloqueio do sistema nervoso simpático, juntamente com os supostos efeitos pleiotrópicos do CVD, não parece ser a estratégia mais adequada para reverter este tipo particular de hipertensão e indicam que as alterações farmacocinéticas induzidas pela CIH no ratio S/(R+S) não justificam a falta de eficácia anti-hipertensora do CVD observada neste modelo animal. Por último, os resultados do presente trabalho suportam ainda a viabilidade da utilização da administração oral voluntária, em alternativa à gavagem, para a administração crónica de uma dose fixa de fármacos anti-hipertensores.---------------------------- ABSTRACT: Hypertension (HT) is a highly prevalent condition, although under diagnosed, in patients with obstructive sleep apnea (OSA). These conditions are closely related and 24-hour ambulatory blood pressure monitoring (ABPM) seems to be the most accurate measurement for diagnosing hypertension in OSA. However, this diagnostic tool is expensive and time-consuming and, therefore, not routinely used. On the other hand, although continuous positive airway pressure (CPAP) is considered the gold standard treatment for symptomatic OSA, its lowering effect on blood pressure (BP) seems to be modest and, therefore, concomitant antihypertensive therapy is still required. Data on antihypertensive drug regimens in patients with OSA are scarce and specific therapeutic guidelines for the pharmacological treatment of hypertension in these patients remain absent. The use of animal models of CIH, which mimic the HT observed in patients with OSA, is extremely important since it is imperative to identify preferred compounds for an adequate BP control in this group of patients. However, studies aimed at investigating the antihypertensive effect of antihypertensive drugs in this animal model are insufficient, and most reports on CIH animal models in which drugs have been tested were not designed to respond to pharmacological issues. Moreover, when testing antihypertensive drugs (AHDs) it becomes crucial to ensure the selection of a non-invasive and stress-free method for drug delivery. Although gavage is effective and a widely performed technique for daily dosing in laboratory rodents, it comprises a sequence of potentially stressful procedures for laboratory animals that may constitute bias for the experimental results. The overall goal of the present translational research was to contribute to identify more effective AHDs for the treatment of hypertension in patients with OSA and investigate underlying mechanisms of systemic effects associated with OSA, as well as its modulation by AHDs. The specific aims were: first, to find new predictors based on anthropometric measures to identify patients that misclassify themselves as non-hypertensive, and thereby promote the selective use of ABPM; second, to investigate a hypothetical association between ongoing antihypertensive regimens and BP control rates in patients with OSA, before and after CPAP adaptation; third, to determine, in a rat model of CIH-induced hypertension, the efficacy of carvedilol (CVD), a nonselective beta-blocker with intrinsic anti-α1-adrenergic activity and antioxidant properties; fourth, to explore the effects of CIH on the pharmacokinetics profile of CVD and fifth, to investigate an alternative method to gavage, for chronic administration of AHDs to laboratory rats. For that, in the first phase of this project, we used a sizeable sample of patients with OSA (n=369), that attended a first visit at Centro Hospitalar Lisboa Norte, EPE Sleep Unit, and underwent overnight polysomnography, 24-h ABPM and filled a questionnaire that included ongoing antihypertensive medication profile registration. In the second phase, a rat experimental model of HT induced by a paradigm of CIH that simulates OSA was used. The main findings of this work were: first, body mass index (BMI) and neck circumference (NC) were identified as independent predictors of hypertension misclassification in patients suspected of OSA; second, in patients with OSA, BP control is independent of both the antihypertensive regimen and the number of antihypertensive drugs, either before or after CPAP adaptation; third, although the doses of 10, 30 and 50 mg/Kg of CVD promoted a significant reduction in heart rate, no decrease in mean arterial pressure was observed; fourth, the S/(R+S) ratios of CVD enantiomers, between rats exposed to CIH and normoxic conditions, were different and fifth, voluntary ingestion proved to be an effective method for a controlled daily dose administration, with a define timetable, that is independent of handling and restraint procedures. In conclusion, the clinical study showed that BP control in OSA patients is independent of both the antihypertensive regimen and the number of antihypertensive drugs. Additionally, our results highlight the lack of validity of self-reported hypertension and suggest that all patients suspected of OSA with undiagnosed hypertension and with a BMI and NC above 27 Kg/m2 and 39 cm should be screened for hypertension, through ABPM. The results attained in the rat model of HT related to CIH suggest that the blockade of the sympathetic nervous system together with the putative pleiotropic effects of carvedilol is not able to revert hypertension induced by CIH and point out that the pharmacokinetic changes induced by CIH on S/(R+S) ratio are not apparently responsible for the lack of efficacy of carvedilol in reversing this particular type of hypertension. Finally, the results here presented support the use of voluntary oral administration as a viable alternative to gavage for chronic administration of a fixed dose of AHDs.
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Prolonged total food deprivation in non-obese adults is rare, and few studies have documented body composition changes in this setting. In a group of eight hunger strikers who refused alimentation for 43 days, water and energy compartments were estimated, aiming to assess the impact of progressive starvation. Measurements included body mass index (BMI), triceps skinfold (TSF), arm muscle circumference (AMC), and bioimpedance (BIA) determinations of water, fat, lean body mass (LBM), and total resistance. Indirect calorimetry was also performed in one occasion. The age of the group was 43.3±6.2 years (seven males, one female). Only water, intermittent vitamins and electrolytes were ingested, and average weight loss reached 17.9%. On the last two days of the fast (43rd-44th day) rapid intravenous fluid, electrolyte, and vitamin replenishment were provided before proceeding with realimentation. Body fat decreased approximately 60% (BIA and TSF), whereas BMI reduced only 18%. Initial fat was estimated by BIA as 52.2±5.4% of body weight, and even on the 43rd day it was still measured as 19.7±3.8% of weight. TSF findings were much lower and commensurate with other anthropometric results. Water was comparatively low with high total resistance, and these findings rapidly reversed upon the intravenous rapid hydration. At the end of the starvation period, BMI (21.5±2.6 kg/m²) and most anthropometric determinations were still acceptable, suggesting efficient energy and muscle conservation. Conclusions: 1) All compartments diminished during fasting, but body fat was by far the most affected; 2) Total water was low and total body resistance comparatively elevated, but these findings rapidly reversed upon rehydration; 3) Exaggerated fat percentage estimates from BIA tests and simultaneous increase in lean body mass estimates suggested that this method was inappropriate for assessing energy compartments in the studied population; 4) Patients were not morphologically malnourished after 43 days of fasting; however, the prognostic impact of other impairments was not considered in this analysis.