Effect of zinc administration on thyrotropin releasing hormone-stimulated prolactinemia in healthy men

Previous in vitro studies have demonstrated zinc (Zn++) inhibition of basal and of potassium (K+) or thyrotropin-releasing hormone (TRH)-stimulated prolactin (PRL) secretion, in a selective, reversible, and dose-dependent manner. Thus, Zn++ may regulate physiologically pituitary PRL secretion. Furthermore, studies with patients with uremia, cirrhosis or prolactinoma, have shown the coexistence of hypozincemia and hyperprolactinemia and zinc supplementation did not correct hyperprolactinemia in these patients. In normal individuals Zn++ administration produced controversial results on PRL secretion. Here, we investigated whether zinc administration affects TRH-stimulated PRL in healthy men. We found that Zn++ administration does not change the TRH-stimulated PRL. Therefore, in normal conditions, Zn++ does not inhibit TRH-stimulated prolactinemia. In addition, we found that acute increases of blood PRL and TRH do not alter blood Zn++ levels.

Zinc supplementation does not inhibit basal and metoclopramide-stimulated prolactinemia secretion in healthy men

Dopamine (DA) and zinc (Zn++) share common mechanisms in their inhibition of prolactin (PRL) secretion. Both substances are present in the same brain areas, where Zn++ is released together with DA, suggesting a modulatory effect of Zn++ on dopaminergic receptors. The aim of the present study was to evaluate the effect of Zn supplementation on basal and PRL secretion stimulated by metoclopramide (MCP), a dopaminergic antagonist. Seven healthy men were evaluated in controlled study, where MCP (5 mg) was given intravenously, before and after 3 months of oral Zn++ (25 mg) administration. Our results indicate that chronic Zn++ administration does not change basal or MCP-stimulated plasma PRL secretion suggesting that, in humans, Zn++ does not interfere on PRL secretion mediated through dopaminergic receptors.

Physical inactivity and related barriers: A study in a community dwelling of older brazilians

This study sought to investigate the prevalence of physical inactivity and related barriers in older Brazilian adults. A cross-sectional, population-based study was conducted, and a stratified random sampling procedure was used. A total of 359 older adults were interviewed. The long version of the International Physical Activity Questionnaire (IPAQ) and the Questionnaire of Barriers to Physical Activity Practice were used to assess physical activity level and barriers, respectively. No statistically significant difference was observed on the prevalence of physical inactivity in either gender or age groups. Regarding barriers, the proportion of 9 out of 22 barriers was statistically significant between men and women. Self-reported physical inactivity/activity in older Brazilian adults continues to be a concern. Uncommonly, older males reported a higher prevalence of physical inactivity compared to their counterparts. Additionally, physical inactivity prevalence continued to increase with the aging process. Yet, personal barriers such as lack of time and poor health were strongly associated with physical inactivity. The results of this study may help health professionals and public policy makers to better address the issues related to a healthy lifestyle among older adults and promote physical activity among Brazilian older adults and in other countries with similar characteristics. © 2012 Sebastião Gobbi et al.

Diversity of eating patterns in older adults: A new scenario?

OBJETIVO: Identificar padrões alimentares e a distribuição dos mesmos, em uma amostra representativa de idosos do município de Botucatu, São Paulo.MÉTODOS: Estudo transversal, ocorrido entre março e junho de 2011, com 355 idosos cadastrados na rede básica de saúde do município, selecionados por amostragem estratificada entre as unidades de saúde. Aplicou-se um questionário de frequência alimentar e questionário sociodemográfico. Padrões alimentares foram identificados utilizando-se análise de componentes principais. Escores de consumo individual foram divididos em tercis, caracterizando a adesão baixa, moderada e alta dos indivíduos para cada padrão alimentar. Realizaram-se análises entre os tercis dos padrões alimentares e as variáveis sociodemográficas.RESULTADOS: Identificaram-se seis padrões alimentares: saudável; lanches e refeição de final de semana; frutas; light e integral; dieta branda; e tradicional. A alta adesão aos padrões saudável e frutas é atingida por indivíduos que cursaram até o primário; e a alta adesão ao padrão lanches e refeição de final de semana é mais prevalente no sexo masculino e em indivíduos com nível máximo de escolaridade. A alta adesão aos padrões light e integral e dieta branda é mais prevalente no sexo feminino, sendo este último padrão também característico de idosos em idade mais avançada.CONCLUSÃO: Identificou-se uma diversidade de padrões alimentares nessa população de idosos e o comportamento alimentar variou de acordo com as condições sociodemográficas inseridas no grupo.

Lower limb muscle coactivation levels in healthy younger and older adults during functional dual-task gait

The purpose of this study was to investigate the influence of daily cognitive task on stiffness of old and young female adults during the gait. The study included 17 physically active younger and 18 older women, with low risk of falls. The volunteers were asked to walk on the treadmill at two different gait conditions: normal gait and functional dual-task gait. The electromyographic signals were collected of the lower limb muscles. The percentage of coactivation for the tibialis anterior/gastrocnemius lateralis and tibialis anterior/soleus were significantly higher in elderly than in younger in the normal gait and dual-task gait. Our results suggest that the elderly have a greater stiffness in the ankle joint during gait normal and daily dual task gait. Thus, we conclude that challenging cognitively situations during the gait may increase the risk of falls in this population.

A single bout of exercise with a flexible pole induces significant cardiac autonomic responses in healthy men

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Step Counting and Energy Expenditure Estimation in Patients With Chronic Obstructive Pulmonary Disease and Healthy Elderly: Accuracy of 2 Motion Sensors

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Incremental Shuttle Walk Test in Older Brazilian Adults

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação do estado nutricional de indivíduos adultos sadios de classe média: ingestão energética e protéica, antropometria, exames bioquímicos do sangue e testes de imunocompetência

Foram estudados parâmetros relacionados ao estado nutricional de 151 adultos sadios, pertencentes à classe média e residindo em Botucatu, SP, Brasil. Valores antropométricos foram maiores nos homens, com exceção da prega tricipital e da área adiposa do braço. O aumento da idade associou-se a aumento dos valores da massa muscular (homens e mulheres) e do peso do corpo, da prega tricipital e da área adiposa do braço (mulheres). Os resultados antropométricos aproximaram-se dos valores referenciais internacionais, mas não foram inteiramente concordantes com eles, sendo inferiores para o peso corpóreo e circunferência e área musculares do braço. Nos indivíduos de menos de 50 anos, os valores da ingestão energética foram ligeiramente inferiores aos níveis recomendados. A ingestão protéica foi adequada. Os valores médios das proteínas e lípides do soro foram similares aos valores de referência. Testes de hipersensibilidade cutânea são apresentados como uma prova funcional para avaliação do estado nutricional.

Gait analysis in clinically healthy sheep from three different age groups using a pressure-sensitive walkway

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of blood viscosity to cerebral blood flow in older humans compared to young subjects

Objective: Since blood viscosity (BV) is one of the most important factors determining blood flow, this study aimed to investigate the possible correlation between increased blood viscosity and reduction of regional cerebral blood flow (rCBF) in healthy ageing.Methods: Male subjects were distributed in two groups: "young", aged 20-30 (27 volunteers), or "elderly", aged 60-70 (50 volunteers). Whole blood viscosity was obtained with a Wells-Brookfield Cone/Plate Viscometer. Cerebral blood flow was analysed by means of single photon emission computed tomography (SPECT).Results: The mean BV values were 3.28 +/- 0.43 mPa in the group of young volunteers and 4.33 +/- 0.73 mPa in the group of elderly volunteers (t = -6.9, p < 0.0001). The elderly had a lower blood flow than the young in the following regions: bilateral parietal; temporal-parietal and temporal of the left hemisphere. Pearson's correlation between BV and rCBF showed a good inverse correlation when the BV was above 3.95 +/- 0.83 mPa.Conclusions: Our results point to a close relationship between the two parameters analysed, BV and rCBF. The impairment in rCBF observed in the elderly volunteers might be due to an increase in BV, among other factors.Significance: These findings suggest interesting possibilities for the treatment/prevention of brain ageing. (C) 2011 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Treinamento com pesos, modelo de programa sistematizado para a terceira idade

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Drinking patterns between men and women in two distinct Brazilian communities

OBJETIVO: Realizou-se um inquérito para comparar diferenças de gênero nos padrões de consumo de álcool em duas amostras urbanas, estratificadas e representativas de duas comunidades (B e RJr). MÉTODO: O questionário Genacis (Gênero, Álcool e Cultura: Um Estudo Internacional Gender, Alcohol, and Culture: An Internacional Study) foi utilizado. RESULTADOS: Houve várias diferenças significativas em dados sociodemográficos e de padrões de uso de álcool entre essas duas amostras. Uma delas tinha população mais velha, educada, católica, branca e mais mulheres na força de trabalho. Dados da comunidade B mostraram que mulheres e homens tiveram padrões similares de consumo de álcool. RJr teve uso de álcool mais alto entre homens e 22% dos homens abaixo de 49 anos de idade tinham padrão de uso do tipo binge. DISCUSSÃO: O acesso, tabagismo, renda e ter um parceiro com consumo pesado de álcool foram fatores de risco importantes para o consumo das mulheres. CONCLUSÕES: Este estudo mostra que quando os papéis das mulheres se tornam similares aos dos homens, modificam seu padrão de consumo de álcool.

Site-specific concentrations of carotenoids in adipose tissue: relations with dietary and serum carotenoid concentrations in healthy adults

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Zinc does not inhibit prolactin secretion during insulin-induced hypoglycemia in normal men

Zinc (Zn ++) has been shown as an important physiological inhibitor of pituitary PRL release, and Zn ++ and PRL could be involved in a negative feedback regulatory loop. However, this inhibitory effect has not been detected in humans with regard to thyrotropin releasing hormone (TRH), dopamine (DA) and histamine (HA) neurotransmitters. In order to investigate this topic, Zn ++ was acutely and chronically administered to five healthy men to observe the probable inhibitory effect on PRL release during insulin-induced hypoglycemia. The positive PRL response to hypoglycemia has generally been considered to be mediated via the hypothalamus by adrenergic, serotoninergic, histaminergic, opioid-peptidergic and TRH neurotransmitters. The results showed that Zn ++ was not able to inhibit the PRL release during insulin-induced hypoglycemia. Under these conditions, Zn ++ does not block hypothalamic neurotransmitters stimulated by hypoglycemia, thus excluding its clinical application in human beings. On the other hand, the effect of acute stress, such as hypoglycemia, on the serum Zn ++ profile was not observed. ©2006 Dustri-Verlag Dr. K. Feistle.