30 research outputs found
The Interaction of Hypotaurine and Other Sulfinates with Reactive Oxygen and Nitrogen Species:A Survey of Reaction Mechanisms
Considerable strides have been made in understanding the oxidative mechanisms involved in the final steps of the cysteine pathway leading to taurine. The oxidation of sulfinates, hypotaurine and cysteine sulfinic acid, to the respective sulfonates, taurine and cysteic acid, has never been associated with any specific enzyme. Conversely, there is strong evidence that in vivo formation of taurine and cysteic acid is the result of sulfinate interaction with a variety of biologically relevant oxidants. In the last decade, many experiments have been performed to understand whether peroxynitrite, nitrogen dioxide and carbonate radical anion could be included in the biologically relevant reactive species capable of oxidizing sulfinates. Thanks to this work, it has been possible to highlight two possible reaction mechanisms (direct and indirect reaction) of sulfinates with reactive oxygen and nitrogen species.The sulfinates oxidation, mediated by peroxynitrite, is an example of both reaction mechanisms: through a two-electron-direct-reaction with peroxynitrite or through a one-electron-indirect-transfer reaction. In the indirect mechanism, the peroxynitrite homolysis releases hydroxyl and nitrogen dioxide radical and in addition the degradation of short-lived adduct formed by peroxynitrite and CO2 can generate carbonate radical anion. The reaction of hypotaurine and cysteine sulfinic acid with peroxynitrite-derived radicals is accompanied by extensive oxygen uptake with the generation of transient intermediates, which can begin a reaction by an oxygen-dependent mechanism with the sulfonates, taurine, and cysteic acid as final products. Due to pulse radiolysis studies, it has been shown that transient sulfonyl radicals (RSO2(•)) have been produced during the oxidation of both sulfinates by one-electron transfer reaction.The purpose is to analyze all the aspects of the reactive mechanism in the sulfinic group oxidation of hypotaurine and cysteine sulfinic acid through the results obtained from our laboratory in recent years
Non-alcoholic fatty liver disease (NAFLD) in different populations: A clinical and epidemiological study – sample of São José do Rio Preto
Identification of Laser Intensity Assuring the Destruction of Target Region of Biological Tissue Using the Gradient Method and Generalized Dual-Phase Lag Equation
Seismic swarms, fault plane solutions, and stress tensors for São Miguel Island central region (Azores)
Hábito alimentar, nÃveis de lipÃdios sangüÃneos e o status antioxidante de adultos jovens fumantes e não fumantes Food habits, blood lipid levels and antioxidant status of young adults smokers and non-smokers
OBJETIVO: Avaliar o hábito alimentar, os nÃveis dos lipÃdios sangüÃneos e o status antioxidante de jovens fumantes e não fumantes. MÉTODOS: Trata-se de um estudo transversal em que 68 indivÃduos, de 18 a 26 anos, emparelhados por sexo e idade, foram divididos em dois grupos: fumantes (n=34) e não fumantes (n=34). Os voluntários selecionados em instituições de ensino, em Viçosa (MG) foram questionados quanto a: hábito de fumar, consumo de bebidas alcoólicas e atividade fÃsica; também foi estimada a dependência nicotÃnica. O hábito alimentar foi avaliado por questionário de freqüência de consumo. Quantificaram-se nÃveis séricos de lipÃdios, nÃvel plasmático de malondialdeÃdo, vitamina E e vitamina C. RESULTADOS: Os jovens começaram a fumar precocemente, independentemente do sexo. O hábito de fumar foi estratificado e encontrou-se 58,8% de fumantes leves e 41,2% de fumantes pesados. Os fumantes apresentaram hábitos alimentares inadequados e consumo freqüente de bebida alcoólica. De acordo com a recomendação do International Physical Activity Questionnaire 69% dos fumantes eram ativos e 27,6% eram muito ativos. Não se observou diferença significante na concentração sérica de lipÃdios entre fumantes e não fumantes. No grupo de fumantes mulheres, verificou-se correlação positiva entre o número de cigarros fumados por dia e os triglicerÃdeos séricos (r=0,824 e p=0,0001) e também entre o tempo que fumavam em anos e o nÃvel de colesterol total (r=0,523 e p=0,031). Os fumantes apresentaram concentração inferior de vitaminas E e C (p=0,002 e p=<0,001, respectivamente) e a concentração de malondialdeÃdo plasmático correlacionou-se ao tempo de tabagismo em anos (r=0,352 e p=0,041). CONCLUSÃO: O grupo de fumantes apresentou hábito alimentar inadequado, principalmente para alimentos gordurosos, e consumo freqüente de bebida alcoólica. Os valores para malondialdeÃdo plasmático apresentaram correlação positiva com o tempo de tabagismo, mas não com o número de cigarros fumados por dia.<br>OBJECTIVE: The objective was to evaluate the food habits, blood lipid levels and antioxidant status of young adult smokers and non smokers. METHODS: This cross-sectional study divided 68 individuals aged 18 to 26 years, matched for age and sex, into two groups: smokers (n=34) and non-smokers (n=34). The individuals, selected from schools in Viçosa (MG), were asked about smoking status, consumption of alcoholic beverages and physical activity levels. Nicotine dependence was also estimated. The Food Frequency Questionnaire was used to assess food habits. Serum levels of lipids, malondialdehyde, vitamin E and vitamin C were measured. RESULTS: The smokers started smoking early, regardless of sex. The smokers were further stratified into two groups: light smokers (58.8%) and heavy smokers (41.2%). Smokers had inadequate food habits and consumed alcoholic beverages frequently. According to the International Physical Activity Questionnaire, 69% of the smokers were active and 27.6% were very active. There was no significant difference between the serum lipid levels of smokers and non-smokers. In women, there was a positive correlation between the number of cigarettes smoked per day and serum triglyceride levels (r=0.824, p=0.0001) and number of years smoking and total cholesterol levels (r=0.523, p=0.031). Smokers had lower vitamin E and C serum concentrations (p=0.002 and p<0.001, respectively) and the concentration of plasma malondialdehyde correlated with the number of years smoking (r=0.352 and p=0.041). CONCLUSION: The group of smokers presented inadequate food habits, consuming alcoholic beverages frequently and high-fat foods. Plasma malondialdehyde levels were positively correlated with the number of years smoking but not with the number of cigarettes smoked per day
Aneurismas dissecantes intracranianos da circulação posterior relato de três casos e revisão da literatura
As dissecções dos vasos cerebrais é causa rara de acidente vascular cerebral (quarta causa). Geralmente são de aparecimento espontâneo ou após trauma simples. É mais comprometido o sistema carotÃdeo e a evolução costuma ser benigna. As dissecções do sistema vértebro-basilar são menos comuns e a dissecção primária da artéria basilar é rara. As dissecções da circulação posterior têm sido diagnosticadas em proporção crescente, porém, seus mecanismos de lesão, o quadro clÃnico, os critérios de diagnóstico e o tratamento constituem problema da prática neurológica e a taxa de morbidade e mortalidade ainda é alta. Os autores abordam estes problemas e sugerem medidas que possam ser úteis no manuseio dessa patologia. Descrevem-se três casos de dissecção, dois da artéria vertebral e um da artéria basilar. É feito também levantamento de 80 casos já publicados, comparando-os aos três casos descritos