22 resultados para NOXIOUS STIMULI
Resumo:
Background Erectile dysfunction (ED) is a prevalent complication of diabetes, and oxidative stress is an important feature of diabetic ED. Oxidative stress-induced damage plays a pivotal role in the development of tissue alterations. However, the deleterious effects of oxidative stress in the corpus cavernosum with the progression of diabetes remain unclear. The aim of this study was to evaluate systemic and penile oxidative stress status in the early and late stages of diabetes. Methods Male Wistar streptozotocin-diabetic rats (and age-matched controls) were examined 2 (early) and 8 weeks (late) after the induction of diabetes. Systemic oxidative stress was evaluated by urinary H2O2 and the ratio of circulating reduced/oxidized glutathione (GSH/GSSG). Penile oxidative status was assessed by H2O2 production and 3-nitrotyrosine (3-NT) formation. Cavernosal endothelial nitric oxide synthase (eNOS) was analyzed by quantitative immunohistochemistry. Dual immunofluorescence was also performed for 3-NT and α-smooth muscle actin (α-SMA) and eNOS–α-SMA. Results There was a significant increase in urinary H2O2 levels in both diabetic groups. The plasma GSH/GSSG ratio was significantly augmented in late diabetes. In cavernosal tissue, H2O2 production was significantly increased in late diabetes. Reactivity for 3-NT was located predominantly in cavernosal smooth muscle (SM) and was significantly reduced in late diabetes. Quantitative immunohistochemistry revealed a significant decrease in eNOS levels in cavernosal SM and endothelium in late diabetes. Conclusions The findings indicate that the noxious effects of oxidative stress are more prominent in late diabetes. Increased penile protein oxidative modifications and decreased eNOS expression may be responsible for structural and/or functional deregulation, contributing to the progression of diabetes-associated ED.
Resumo:
Epigenetic modulation is found to get involved in multiple neurobehavioral processes. It is believed that different types of environmental stimuli could alter the epigenome of the whole brain or related neural circuits, subsequently contributing to the long-lasting neural plasticity of certain behavioral phenotypes. While the maternal influence on the health of offsprings has been long recognized, recent findings highlight an alternative way for neurobehavioral phenotypes to be passed on to the next generation, i.e., through the male germ line. In this review, we focus specifically on the transgenerational modulation induced by environmental stress, drugs of abuse, and other physical or mental changes (e.g., ageing, metabolism, fear) in fathers, and recapitulate the underlying mechanisms potentially mediating the alterations in epigenome or gene expression of offsprings. Together, these findings suggest that the inheritance of phenotypic traits through male germ-line epigenome may represent the unique manner of adaptation during evolution. Hence, more attention should be paid to the paternal health, given its equivalently important role in affecting neurobehaviors of descendants.
Resumo:
Adult mammalian brains continuously generate new neurons, a phenomenon called adult neurogenesis. Both environmental stimuli and endogenous factors are important regulators of adult neurogenesis. Sleep has an important role in normal brain physiology and its disturbance causes very stressful conditions, which disrupt normal brain physiology. Recently, an influence of sleep in adult neurogenesis has been established, mainly based on sleep deprivation studies. This review provides an overview on how rhythms and sleep cycles regulate hippocampal and subventricular zone neurogenesis, discussing some potential underlying mechanisms. In addition, our review highlights some interacting points between sleep and adult neurogenesis in brain function, such as learning, memory, and mood states, and provides some insights on the effects of antidepressants and hypnotic drugs on adult neurogenesis.
Resumo:
Microbiota is a set of microorganisms resident in gut ecosystem that reacts to psychological stressful stimuli, and is involved in depressed or anxious status in both animals and human being. Interestingly, a series of studies have shown the effects of physical exercise on gut microbiota dynamics, suggesting that gut microbiota regulation might act as one mediator for the effects of exercise on the brain. Recent studies found that gut microbiota dynamics are also regulated by metabolism changes, such as through physical exercise or diet change. Interestingly, physical exercise modulates different population of gut bacteria in compared to food restriction or rich diet, and alleviates gut syndromes to toxin intake. Gut microbiota could as well contribute to the beneficial effects of exercise on cognition and emotion, either directly through serotonin signaling or indirectly by modulating metabolism and exercise performance.
Resumo:
Anxiety disorders are the most common psychiatric disorders observed currently. It is a normal adaptive response to stress that allows coping with adverse situations. Nevertheless, when anxiety becomes excessive or disproportional in relation to the situation that evokes it or when there is not any special object directed at it, such as an irrational dread of routine stimuli, it becomes a disabling disorder and is considered to be pathological. The traditional treatment used is medication and cognitive behavioral psychotherapy, however, last years the practice of physical exercise, specifically aerobic exercise, has been investigated as a new non-pharmacological therapy for anxiety disorders. Thus, the aim of this article was to provide information on research results and key chains related to the therapeutic effects of aerobic exercise compared with other types of interventions to treat anxiety, which may become a useful clinical application in a near future. Researches have shown the effectiveness of alternative treatments, such as physical exercise, minimizing high financial costs and minimizing side effects. The sample analyzed, 66.8% was composed of women and 80% with severity of symptoms anxiety as moderate to severe. The data analyzed in this review allows us to claim that alternative therapies like exercise are effective in controlling and reducing symptoms, as 91% of anxiety disorders surveys have shown effective results in treating. However, there is still disagreement regarding the effect of exercise compared to the use of antidepressant symptoms and cognitive function in anxiety, this suggests that there is no consensus on the correct intensity of aerobic exercise as to achieve the best dose-response, with intensities high to moderate or moderate to mild.
Resumo:
Numa era de globalização, de desenvolvimento tecnológico exponencial e de consumismo exacerbado, a publicidade conquistou o quotidiano das sociedades modernas e seduziu, também, as nossas crianças. Subjacente ao paradigma de que o comportamento humano dá respostas favoráveis a estímulos adequados e apresentados com oportunidade e habilidade (Caetano et al., 2011), colocamos a hipótese de utilização didática de anúncios publicitários na aula de Inglês para o desenvolvimento de competências comunicativas. Este projeto assentou no aproveitamento do potencial que a publicidade oferece, tendo em conta, por um lado, a envolvência sedutora que a torna um meio privilegiado para captar a atenção e veicular informação e, por outro, a prevalência de palavras em Inglês que nela se observa. O estudo, de natureza qualitativa, é o resultado de uma investigação-ação, na qual adotamos uma metodologia baseada num modelo descritivo e interpretativo, através de métodos qualitativos de recolha de dados e análise de informação, que teve como participantes crianças do 4.º ano de escolaridade. Desenvolvemos questionários, como instrumentos de recolha de dados, aplicados a professores e alunos. Construímos, igualmente, guiões de atividades com sugestões de exploração da publicidade no ensino da língua. Comprovamos que a publicidade, aliada ao Inglês, pode ser um valioso recurso no desenvolvimento e aprendizagem das crianças, pois é um material autêntico, motivador, atrai a atenção, possibilita o contacto com situações reais, envolve linguagem verbal e não-verbal e permite a exploração de diferentes temas, o que contribui, certamente, para a compreensão intercultural, a mobilização de saberes e o desenvolvimento do espírito crítico.
Resumo:
O desenvolvimento e proliferação de equipamentos e produtos multimédia, permitindo a combinação de som, imagem e texto despoletou a emergência de novos estímulos que se associam a sensações, novas formas de interagir, de comunicar e também de brincar e aprender. Jogar e brincar são excelentes fontes de estímulos, principalmente para as crianças, pois potenciam a evolução da lógica, do raciocínio, das associações e da capacidade de escolha. No contexto dos jogos, decorrente da evolução tecnológica, o mercado dos jogos digitais tem vindo a expandir-se consideravelmente, nomeadamente na área dos jogos educativos. Os jogos educativos baseados em contos infantis permitem um enriquecimento de experiências, de capacidades sequenciais de lógica e promovem a apetência da criança para fantasiar num mundo paralelo. No entanto, do nosso ponto de vista, o mercado dos jogos digitais ainda tem um longo caminho a percorrer para fornecer de forma equilibrada este tipo de jogos educativos. Com este trabalho abordam-se as potencialidades que os jogos educativos baseados em contos infantis podem ter no desenvolvimento de algumas competências das crianças, nomeadamente através da análise das suas vantagens e dos seus aspetos negativos. O mercado dos jogos digitais é também analisado para determinar os seus contributos e as ideias principais presentes. A componente prática deste trabalho de mestrado contempla a criação de um jogo educativo baseado em contos infantis que corresponda aos interesses das crianças entre os 3 e os 5 anos de idade, e que fomente o desenvolvimento de algumas das suas competências a nível da linguagem. Os testes feitos com o protótipo do jogo permitem aferir a recetividade por parte das crianças. A simplicidade no manuseamento da aplicação e o facto de integrar histórias do imaginário infantil consideram-se fatores positivos e motivadores à utilização do jogo “Contos Baralhados: Brinca com as Histórias”.