63 research outputs found
Corrida em esteira e exercĂcios de força: efeitos agudos da ordem de realização sobre a hipotensĂŁo pĂłs-exercĂcio
Este estudo analisou as respostas de pressĂŁo arterial sistĂłlica (PAS) e pressĂŁo arterial diastĂłlica (PAD) apĂłs duas sessĂ”es de exercĂcio concorrente realizado em diferentes ordens [aerĂłbio-força (AF), e força-aerĂłbio (FA)]. Quinze indivĂduos normotensos foram submetidos a duas sessĂ”es de exercĂcio realizadas em dias distintos na seguinte sequĂȘncia AF e FA. A PAS e PAD foram medidas antes e a cada 15 min durante 60 min de recuperação pĂłs-exercĂcio. Houve hipotensĂŁo pĂłs-exercĂcio (HPE) para PAS, aos 30 min (-7,4 mmHg), 45 min (-12,14 mmHg) e 60 min (-15,14 mmHg) de recuperação na sessĂŁo AF. JĂĄ na FA houve HPE apenas aos 60 min (-8,34 mmHg) de recuperação. A variação da PAS e PAD entre as sessĂ”es revelou HPE maior aos 15 min, 45 min e 60 min na PAS; e aos 45 min na PAD comparando-se AF a FA. A realização de exercĂcio aerĂłbio antes do de força resultou em maior HPE para adultos jovens
High-Density Expression of Ca2+-Permeable ASIC1a Channels in NG2 Glia of Rat Hippocampus
NG2 cells, a fourth type of glial cell in the mammalian CNS, undergo reactive changes in response to a wide variety of brain insults. Recent studies have demonstrated that neuronally expressed acid-sensing ion channels (ASICs) are implicated in various neurological disorders including brain ischemia and seizures. Acidosis is a common feature of acute neurological conditions. It is postulated that a drop in pH may be the link between the pathological process and activation of NG2 cells. Such postulate immediately prompts the following questions: Do NG2 cells express ASICs? If so, what are their functional properties and subunit composition? Here, using a combination of electrophysiology, Ca2+ imaging and immunocytochemistry, we present evidence to demonstrate that NG2 cells of the rat hippocampus express high density of Ca2+-permeable ASIC1a channels compared with several types of hippocampal neurons. First, nucleated patch recordings from NG2 cells revealed high density of proton-activated currents. The magnitude of proton-activated current was pH dependent, with a pH for half-maximal activation of 6.3. Second, the current-voltage relationship showed a reversal close to the equilibrium potential for Na+. Third, psalmotoxin 1, a blocker specific for the ASIC1a channel, largely inhibited proton-activated currents. Fourth, Ca2+ imaging showed that activation of proton-activated channels led to an increase of [Ca2+]i. Finally, immunocytochemistry showed co-localization of ASIC1a and NG2 proteins in the hippocampus. Thus the acid chemosensor, the ASIC1a channel, may serve for inducing membrane depolarization and Ca2+ influx, thereby playing a crucial role in the NG2 cell response to injury following ischemia
Socio-cultural determinants of physical activity across the life course: a 'Determinants of Diet and Physical Activity' (DEDIPAC) umbrella systematic literature review
Objective
Regular physical activity (PA) reduces the risk of disease and premature death. Knowing factors associated with PA might help reducing the disease and economic burden caused by low activity. Studies suggest that socio-cultural factors may affect PA, but systematic overviews of findings across the life course are scarce. This umbrella systematic literature review (SLR) summarizes and evaluates available evidence on socio-cultural determinants of PA in children, adolescents, and adults.
Methods
This manuscript was drafted following the recommendations of the âPreferred Reporting Items for Systematic reviews and Meta-Analysesâ (PRISMA) checklist. The MEDLINE, Web of Science, Scopus, and SPORTDiscus databases were searched for SLRs and meta-analyses (MAs) on observational studies published in English that assessed PA determinants between January 2004 and April 2016. The methodological quality was assessed and relevant information on socio-cultural determinants and any associations with PA was extracted. The available evidence was evaluated based on the importance of potential determinants and the strength of the evidence.
Results
Twenty SLRs and three MAs encompassing 657 eligible primary studies investigated potential socio-cultural PA determinants, with predominantly moderate methodological quality. Twenty-nine potential PA determinants were identified that were primarily assessed in children and adolescents and investigated the micro-environmental home/household level. We found probable evidence that receiving encouragement from significant others and having a companion for PA were associated with higher PA in children and adolescents, and that parental marital status (living with partner) and experiencing parental modeling were not associated with PA in children. Evidence for the other potential determinants was limited, suggestive, or non-conclusive. In adults, quantitative and conclusive data were scarce.
Conclusions
A substantial number of SLRs and MAs investigating potential socio-cultural determinants of PA were identified. Our data suggest that receiving social support from significant others may increase PA levels in children and adolescents, whereas parental marital status is not a determinant in children. Evidence for other potential determinants was limited. This was mainly due to inconsistencies in results on potential socio-cultural determinants of PA across reviews and studies
A many-analysts approach to the relation between religiosity and well-being
The relation between religiosity and well-being is one of the most researched topics in the psychology of religion, yet the directionality and robustness of the effect remains debated. Here, we adopted a many-analysts approach to assess the robustness of this relation based on a new cross-cultural dataset (N=10,535 participants from 24 countries). We recruited 120 analysis teams to investigate (1) whether religious people self-report higher well-being, and (2) whether the relation between religiosity and self-reported well-being depends on perceived cultural norms of religion (i.e., whether it is considered normal and desirable to be religious in a given country). In a two-stage procedure, the teams first created an analysis plan and then executed their planned analysis on the data. For the first research question, all but 3 teams reported positive effect sizes with credible/confidence intervals excluding zero (median reported ÎČ=0.120). For the second research question, this was the case for 65% of the teams (median reported ÎČ=0.039). While most teams applied (multilevel) linear regression models, there was considerable variability in the choice of items used to construct the independent variables, the dependent variable, and the included covariates
Comportamento cardiovascular apĂłs o exercĂcio resistido realizado de diferentes formas e volumes de trabalho
OBJETIVO: Verificar as respostas cardiovasculares apĂłs o exercĂcio resistido realizado de diferentes formas e volumes de trabalho. MĂTODOS: Dez homens saudĂĄveis realizaram em dias diferentes e aleatoriamente sessĂ”es de oito exercĂcios resistidos (18 repetiçÔes e 40% de 1RM) e uma sessĂŁo controle. As sessĂ”es de exercĂcios foram executadas com uma sĂ©rie em circuito (1CIRC), trĂȘs sĂ©ries em circuito (3CIRC), uma sĂ©rie de forma convencional (1CONV) e trĂȘs sĂ©ries de forma convencional (3CONV). A pressĂŁo arterial (PA) e a variabilidade da frequĂȘncia cardĂaca (VFC) foram medidas em repouso e por uma hora apĂłs as sessĂ”es. RESULTADOS: Considerando a mĂ©dia do perĂodo de monitorização, em relação Ă PA sistĂłlica, somente a sessĂŁo 3CIRC (-9,4 ± 3,0mmHg; P = 0,02) promoveu reduçÔes em relação Ă sessĂŁo controle. JĂĄ para a PA diastĂłlica, as sessĂ”es 1CIRC (-5,7 ± 1,8mmHg; P = 0,005), 3CIRC (-8,4 ± 1,6mmHg; P = 0,0002) e 3CONV (-8,6 ± 2,2mmHg; P = 0,0001) ocasionaram reduçÔes em relação Ă sessĂŁo controle. De forma idĂȘntica, a PA mĂ©dia permaneceu reduzida em relação ao controle apĂłs as sessĂ”es 1CIRC (-5,0 ± 1,8mmHg; P = 0,02), 3CIRC (-8,7 ± 1,6mmHg; P = 0,0002) e 3CONV (-7,9 ± 1,9mmHg; P = 0,0006).Em relação Ă FC, a sessĂŁo 3CIRC mostrou valores superiores relação Ă s sessĂ”es 1CONV (P = 0,001) e 3CONV (P = 0,04). A razĂŁo entre os componentes LF/HF da VFC tambĂ©m foi superior em relação ao controle na sessĂŁo 3CIRC. CONCLUSĂO: As sessĂ”es envolvendo mais sĂ©ries de exercĂcios ocasionaram reduçÔes na PA de maneira similar. PorĂ©m, a sessĂŁo 3CIRC acarretou maior esforço cardĂaco pĂłs-esforço
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