636 research outputs found

    Influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training on the plasma cytokine response to maximum sustainable voluntary ventilation

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    The influence of oxidative stress, diaphragm fatigue, and inspiratory muscle training (IMT) on the cytokine response to maximum sustainable voluntary ventilation (MSVV) is unknown. Twelve healthy males were divided equally into an IMT or placebo (PLA) group, and before and after a 6-wk intervention they undertook, on separate days, 1h of (1) passive rest and (2) MSVV, whereby participants undertook volitional hyperpnea at rest that mimicked the breathing and respiratory muscle recruitment patterns commensurate with heavy cycling exercise. Plasma cytokines remained unchanged during passive rest. There was a main effect of time (P < 0.01) for plasma interleukin-1 (IL-1) and interleukin-6 (IL-6) concentrations and a strong trend (P = 0.067) for plasma interleukin-1 receptor antagonist concentration during MSVV. Plasma IL-6 concentration was reduced after IMT by 27 + 18% (main effect of intervention, P = 0.029), whereas there was no change after PLA (P = 0.753). There was no increase in a systemic marker of oxidative stress [DNA damage in peripheral blood mononuclear cells (PBMC)], and diaphragm fatigue was not related to the increases in plasma IL-1 and IL-6 concentrations. A dose-response relationship was observed between respiratory muscle work and minute ventilation and increases in plasma IL-6 concentration. In conclusion, increases in plasma IL-1 and IL-6 concentrations during MSVV were not due to diaphragm fatigue or DNA damage in PBMC. Increases in plasma IL-6 concentration during MSVV are attenuated following IMT, and the plasma IL-6 response is dependent upon the level of respiratory muscle work and minute ventilation

    SENIEUR status of the originating cell donor negates certain ‘anti-immunosenescence’ effects of ebselen and N-acetyl cysteine in human T cell clone cultures

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    BACKGROUND: Damage to T cells of the immune system by reactive oxygen species may result in altered cell function or cell death and thereby potentially impact upon the efficacy of a subsequent immune response. Here, we assess the impact of the antioxidants Ebselen and N-acetyl cysteine on a range of biological markers in human T cells derived from a SENIEUR status donor. In addition, the impact of these antioxidants on different MAP kinase pathways in T cells from donors of different ages was also examined. METHODS: T cell clones were derived from healthy 26, 45 and SENIEUR status 80 year old people and the impact of titrated concentrations of Ebselen or N-acetyl cysteine on their proliferation and in vitro lifespan, GSH:GSSG ratio as well as levels of oxidative DNA damage and on MAP kinase signaling pathways was examined. RESULTS: In this investigation neither Ebselen nor N-acetyl cysteine supplementation had any impact on the biological endpoints examined in the T cells derived from the SENIEUR status 80 year old donor. This is in contrast to the anti-immunosenescent effects of these antioxidants on T cells from donors of 26 or 45 years of age. The analysis of MAP kinases showed that pro-apoptotic pathways become activated in T cells with increasing in vitro age and that Ebselen or N-acetyl cysteine could decrease activation (phosphorylation) in T cells from 26 or 45 year old donors, but not from the SENIEUR status 80 year old donor. CONCLUSIONS: The results of this investigation demonstrate that the biological phenotype of SENIEUR status derived human T cells negates the anti-immunosenescence effects of Ebselen and also N-acetyl cysteine. The results highlight the importance of pre-antioxidant intervention evaluation to determine risk-benefit

    The Association Between Objectively Measured Vision Impairment and Self-Reported Physical Activity Among 34,129 Adults Aged ≥50 Years in Six Low- and Middle-Income Countries

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    The authors investigated the association between vision impairment and physical activity among older adults from low- and middle-income countries. Visual acuity was measured using the tumbling ElogMAR chart, and vision impairment was defined as visual acuity worse than 6/18 (0.48 logMAR) in the better seeing eye. Physical activity was assessed by the Global Physical Activity Questionnaire. Multivariable logistic regression and meta-analysis were conducted to assess associations. The sample included 34,129 individuals aged 50–114 years (mean [SD] age 62.4 [16.0] years; 47.9% male). After adjustment for confounders, near vision impairment was not significantly associated with low physical activity, but far vision impairment showed a significant association (odds ratio = 1.32; 95% confidence interval [1.17, 1.49], I2 = 0.0%). Far vision impairment was dose-dependently associated with low physical activity (e.g., severe [<6/10] vs. no [≥6/12] far vision impairment; odds ratio = 1.80; 95% confidence interval [1.03, 3.15]). Interventions to address low levels of physical activity in the visually impaired in low- and middle-income countries should target those with far vision impairment

    Temporal trends of carbonated soft-drink consumption among adolescents aged 12-15 years from 18 countries from Africa, Asia, and the Americas

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    Carbonated soft-drink consumption is detrimental to multiple facets of adolescent health. However, little is known about temporal trends in carbonated soft-drink consumption among adolescents, particularly in non-Western countries. Therefore, we aimed to examine this trend in representative samples of school-going adolescents from 18 countries in Africa, Asia, and the Americas.Cross-sectional data from the Global School-based Student Health Survey 2009-2017 were analyzed. Carbonated soft-drink consumption referred to drinking carbonated soft-drinks at least once per day in the past 30 days. The prevalence of carbonated soft-drink consumption was calculated for each survey, and crude linear trends were assessed by linear regression models. Data on 74,055 students aged 12-15 years were analyzed [mean (SD) age 13.9 (1.0) years; 49.2% boys]. The overall mean prevalence of carbonated soft-drink consumption was 42.1%. Of the 18 countries included in the study, significant decreasing, increasing, and stable trends of carbonated soft-drink consumption were observed in seven, two, and nine countries, respectively. The most drastic decrease was observed in Kuwait between 2011 (74.4%) and 2015 (51.7%). Even in countries with significant decreasing trends, the decrease was rather modest, while some countries with stable trends had very high prevalence across time (e.g., Suriname 80.5% in 2009 and 79.4% in 2016). The prevalence of carbonated soft-drink consumption was high in all countries included in the present analysis, despite decreasing trends being observed in some. Public health initiatives to reduce the consumption of carbonated soft-drink consumption among adolescents are urgently required

    The effects of inspiratory muscle training in older adults

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    Purpose: Declining inspiratory muscle function and structure and systemic low-level inflammation and oxidative stress may contribute to morbidity and mortality during normal ageing. Therefore, we examined the effects of inspiratory muscle training (IMT) in older adults on inspiratory muscle function and structure and systemic inflammation and oxidative stress, and re-examined the reported positive effects of IMT on respiratory muscle strength, inspiratory muscle endurance, spirometry, exercise performance, physical activity levels (PAL) and quality of life (QoL). Methods: Thirty-four healthy older adults (68 ± 3 years) with normal spirometry, respiratory muscle strength and physical fitness were divided equally into a pressure-threshold IMT or sham-hypoxic placebo group. Before and after an 8 week intervention, measurements were taken for dynamic inspiratory muscle function and inspiratory muscle endurance using a weighted plunger pressure-threshold loading device, diaphragm thickness using B-mode ultrasonography, plasma cytokine concentrations using immunoassays, DNA damage levels in peripheral blood mononuclear cells (PBMC) using Comet Assays, spirometry, maximal mouth pressures, exercise performance using a six minute walk test, PAL using a questionnaire and accelerometry, and QoL using a questionnaire

    Association between food insecurity and depressive symptoms among adolescents aged 12-15 years from 22 low- and middle-income countries

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    Food insecurity may be a risk factor for depression in adolescents. However, data on this topic from low- and middle-income countries (LMICs) are scarce, despite food insecurity being most common in LMICs. Therefore, we aimed to examine the association between food-insecurity and depressive symptoms among school-going adolescents from 22 LMICs. Cross-sectional data from the Global school-based Student Health Survey were analyzed. Self-report measures assessed past 12-month depressive symptoms and past 30-day food insecurity (hunger). Multivariable logistic regression and meta-analysis were conducted to assess associations. Data on 48,401 adolescents aged 12–15 years were analyzed [mean (SD) age 13.8 (0.9) years; 51.4 % females]. The prevalence of depressive symptoms was 29.3 %, and those of moderate and severe food insecurity were 45.0 and 6.3 %, respectively. After adjustment for potential confounders, compared to no food insecurity, the pooled OR (95 %CI) of moderate and severe food insecurity were 1.36 (1.30–1.42) and 1.81 (1.67–1.97), respectively. The level of between-country heterogeneity was low. Food insecurity was associated with significantly higher odds for depressive symptoms among adolescents in LMICs. Policies to address food insecurity may also help prevent depression in this population, pending future longitudinal research.</p

    Furthering alternative cultures of valuation in higher education research

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    The value of higher education is often implicit or assumed in educational research. The underlying and antecedent premises that shape and influence debates about value remain unchallenged which perpetuates the dominant, but limiting, terms of the debate and fosters reductionism. I proceed on the premise that analyses of value are not self–supporting or self-referential but are embedded within prevailing cultures of valuation. I contend that challenging, and providing alternatives to, dominant narratives of higher education requires an appreciation of those cultures. I therefore highlight some of the existing cultures of valuation and their influence. I then propose Sayer’s concept of lay normativity as a culture of valuation and discuss how it translates into the practices of research into higher education, specifically the practice of analysis. I animate the discussion by detecting the presence of lay normativity in the evaluative space of the capability approach

    Unclean Cooking Fuel Use and Slow Gait Speed Among Older Adults From 6 Countries

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    Background Outdoor air pollution has been reported to be associated with frailty (including slow gait speed) in older adults. However, to date, no literature exists on the association between indoor air pollution (eg, unclean cooking fuel use) and gait speed. Therefore, we aimed to examine the cross-sectional association between unclean cooking fuel use and gait speed in a sample of older adults from 6 low- and middle-income countries (China, Ghana, India, Mexico, Russia, and South Africa). Methods Cross-sectional, nationally representative data from the World Health Organization Study on global AGEing and adult health were analyzed. Unclean cooking fuel use referred to the use of kerosene/paraffin, coal/charcoal, wood, agriculture/crop, animal dung, and shrubs/grass based on self-report. Slow gait speed referred to the slowest quintile based on height, age, and sex-stratified values. Multivariable logistic regression and meta-analysis were done to assess associations. Results Data on 14 585 individuals aged ≥65 years were analyzed (mean [standard deviation] age 72.6 [11.4] years; 45.0% males). Unclean cooking fuel use (vs clean cooking fuel use) was significantly associated with higher odds for slow gait speed (odds ratio = 1.45; 95% confidence interval: 1.14–1.85) based on a meta-analysis using country-wise estimates. The level of between-country heterogeneity was very low (I2 = 0%). Conclusions Unclean cooking fuel use was associated with slower gait speed among older adults. Future studies of longitudinal design are warranted to provide insight into the underlying mechanisms and possible causality
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