154 research outputs found
Exposure to Household Air Pollution from Biomass-Burning Cookstoves and HbA1c and Diabetic Status Among Honduran Women
Household air pollution from biomass cookstoves is estimated to be responsible for more than two and a half million premature deaths annually, primarily in low and middleâincome countries where cardiometabolic disorders, such as Type II Diabetes, are increasing. Growing evidence supports a link between ambient air pollution and diabetes, but evidence for household air pollution is limited. This crossâsectional study of 142 women (72 with traditional stoves and 70 with cleanerâburning Justa stoves) in rural Honduras evaluated the association of exposure to household air pollution (stove type, 24âhour average kitchen and personal fine particulate matter [PM2.5] mass and black carbon) with glycated hemoglobin (HbA1c) levels and diabetic status based on HbA1c levels. The prevalence ratio (PR) per interquartile range increase in pollution concentration indicated higher prevalence of prediabetes/diabetes (vs normal HbA1c) for all pollutant measures (eg, PR per 84 Îźg/m3 increase in personal PM2.5, 1.49; 95% confidence interval [CI], 1.11â2.01). Results for HbA1c as a continuous variable were generally in the hypothesized direction. These results provide some evidence linking household air pollution with the prevalence of prediabetes/diabetes, and, if confirmed, suggest that the global public health impact of household air pollution may be broader than currently estimated
Exposure to Household Air Pollution from Biomass Cookstoves and Blood Pressure Among Women in Rural Honduras: A CrossâSectional Study
Growing evidence links household air pollution exposure from biomass cookstoves with elevated blood pressure. We assessed crossâsectional associations of 24âhour mean concentrations of personal and kitchen fine particulate matter (PM2.5), black carbon (BC), and stove type with blood pressure, adjusting for confounders, among 147 women using traditional or cleanerâburning Justa stoves in Honduras. We investigated effect modification by age and body mass index. Traditional stove users had mean (standard deviation) personal and kitchen 24âhour PM2.5 concentrations of 126 Îźg/m3 (77) and 360 Îźg/m3 (374), while Justa stove usersâ exposures were 66 Îźg/m3 (38) and 137 Îźg/m3(194), respectively. BC concentrations were similarly lower among Justa stove users. Adjusted mean systolic blood pressure was 2.5 mm Hg higher (95% CI, 0.7â4.3) per unit increase in natural logâtransformed kitchen PM2.5 concentration; results were stronger among women of 40 years or older (5.2 mm Hg increase, 95% CI, 2.3â8.1). Adjusted odds of borderline high and high blood pressure (categorized) were also elevated (odds ratio = 1.5, 95% CI, 1.0â2.3). Some results included null values and are suggestive. Results suggest that reduced household air pollution, even when concentrations exceed air quality guidelines, may help lower cardiovascular disease risk, particularly among older subgroups
Exposure to Household Air Pollution from Biomass Cookstoves and Levels of Fractional Exhaled Nitric Oxide (FeNO) among Honduran Women
Household air pollution is estimated to be responsible for nearly three million premature deaths annually. Measuring fractional exhaled nitric oxide (FeNO) may improve the limited understanding of the association of household air pollution and airway inflammation. We evaluated the cross-sectional association of FeNO with exposure to household air pollution (24-h average kitchen and personal fine particulate matter and black carbon; stove type) among 139 women in rural Honduras using traditional stoves or cleaner-burning Justastoves. We additionally evaluated interaction by age. Results were generally consistent with a null association; we did not observe a consistent pattern for interaction by age. Evidence from ambient and household air pollution regarding FeNO is inconsistent, and may be attributable to differing study populations, exposures, and FeNO measurement procedures (e.g., the flow rate used to measure FeNO)
Exposure to household air pollution from biomassâ burning cookstoves and HbA1c and diabetic status among Honduran women
Household air pollution from biomass cookstoves is estimated to be responsible for more than two and a half million premature deaths annually, primarily in low and middleâ income countries where cardiometabolic disorders, such as Type II Diabetes, are increasing. Growing evidence supports a link between ambient air pollution and diabetes, but evidence for household air pollution is limited. This crossâ sectional study of 142 women (72 with traditional stoves and 70 with cleanerâ burning Justa stoves) in rural Honduras evaluated the association of exposure to household air pollution (stove type, 24â hour average kitchen and personal fine particulate matter [PM2.5] mass and black carbon) with glycated hemoglobin (HbA1c) levels and diabetic status based on HbA1c levels. The prevalence ratio (PR) per interquartile range increase in pollution concentration indicated higher prevalence of prediabetes/diabetes (vs normal HbA1c) for all pollutant measures (eg, PR per 84Ă ĂÂźg/m3 increase in personal PM2.5, 1.49; 95% confidence interval [CI], 1.11â 2.01). Results for HbA1c as a continuous variable were generally in the hypothesized direction. These results provide some evidence linking household air pollution with the prevalence of prediabetes/diabetes, and, if confirmed, suggest that the global public health impact of household air pollution may be broader than currently estimated.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145588/1/ina12484_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145588/2/ina12484.pd
Exposure to household air pollution from biomass cookstoves and blood pressure among women in rural Honduras: A crossâ sectional study
Growing evidence links household air pollution exposure from biomass cookstoves with elevated blood pressure. We assessed crossâ sectional associations of 24â hour mean concentrations of personal and kitchen fine particulate matter (PM2.5), black carbon (BC), and stove type with blood pressure, adjusting for confounders, among 147 women using traditional or cleanerâ burning Justa stoves in Honduras. We investigated effect modification by age and body mass index. Traditional stove users had mean (standard deviation) personal and kitchen 24â hour PM2.5 concentrations of 126Ă ĂÂźg/m3 (77) and 360Ă ĂÂźg/m3 (374), while Justa stove usersâ exposures were 66Ă ĂÂźg/m3 (38) and 137Ă ĂÂźg/m3 (194), respectively. BC concentrations were similarly lower among Justa stove users. Adjusted mean systolic blood pressure was 2.5Ă mm Hg higher (95% CI, 0.7â 4.3) per unit increase in natural logâ transformed kitchen PM2.5 concentration; results were stronger among women of 40Ă years or older (5.2Ă mm Hg increase, 95% CI, 2.3â 8.1). Adjusted odds of borderline high and high blood pressure (categorized) were also elevated (odds ratioĂ =Ă 1.5, 95% CI, 1.0â 2.3). Some results included null values and are suggestive. Results suggest that reduced household air pollution, even when concentrations exceed air quality guidelines, may help lower cardiovascular disease risk, particularly among older subgroups.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146816/1/ina12507.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146816/2/ina12507_am.pd
Kinesin expands and stabilizes the GDP-microtubule lattice
Kinesin-1 is a nanoscale molecular motor that walks towards the fast-growing (plus) ends of microtubules, hauling molecular cargo to specific reaction sites in cells. Kinesin-driven transport is central to the self-organization of eukaryotic cells and shows great promise as a tool for nano-engineering1. Recent work hints that kinesin may also play a role in modulating the stability of its microtubule track, both in vitro2,3 and in vivo4, but the results are conflicting5,6,7 and the mechanisms are unclear. Here, we report a new dimension to the kinesinâmicrotubule interaction, whereby strong-binding state (adenosine triphosphate (ATP)-bound and apo) kinesin-1 motor domains inhibit the shrinkage of guanosine diphosphate (GDP) microtubules by up to two orders of magnitude and expand their lattice spacing by ~1.6%. Our data reveal an unexpected mechanism by which the mechanochemical cycles of kinesin and tubulin interlock, and so allow motile kinesins to influence the structure, stability and mechanics of their microtubule track
Formation of Mobile Chromatin-Associated Nuclear Foci Containing HIV-1 Vpr and VPRBP Is Critical for the Induction of G2 Cell Cycle Arrest
HIV-1 Viral protein R (Vpr) induces a cell cycle arrest at the G2/M phase by activating the ATR DNA damage/stress checkpoint. Recently, we and several other groups showed that Vpr performs this activity by recruiting the DDB1-CUL4A (VPRBP) E3 ubiquitin ligase. While recruitment of this E3 ubiquitin ligase complex has been shown to be required for G2 arrest, the subcellular compartment where this complex forms and functionally acts is unknown. Herein, using immunofluorescence and confocal microscopy, we show that Vpr forms nuclear foci in several cell types including HeLa cells and primary CD4+ T-lymphocytes. These nuclear foci contain VPRBP and partially overlap with DNA repair foci components such as Îł-H2AX, 53BP1 and RPA32. While treatment with the non-specific ATR inhibitor caffeine or depletion of VPRBP by siRNA did not inhibit formation of Vpr nuclear foci, mutations in the C-terminal domain of Vpr and cytoplasmic sequestration of Vpr by overexpression of Gag-Pol resulted in impaired formation of these nuclear structures and defective G2 arrest. Consistently, we observed that G2 arrest-competent sooty mangabey Vpr could form these foci but not its G2 arrest-defective paralog Vpx, suggesting that formation of Vpr nuclear foci represents a critical early event in the induction of G2 arrest. Indeed, we found that Vpr could associate to chromatin via its C-terminal domain and that it could form a complex with VPRBP on chromatin. Finally, analysis of Vpr nuclear foci by time-lapse microscopy showed that they were highly mobile and stable structures. Overall, our results suggest that Vpr recruits the DDB1-CUL4A (VPRBP) E3 ligase to these nuclear foci and uses these mobile structures to target a chromatin-bound cellular substrate for ubiquitination in order to induce DNA damage/replication stress, ultimately leading to ATR activation and G2 cell cycle arrest
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COVID-19, systemic crisis, and possible implications for the wild meat trade in sub-Saharan Africa
Wild animals play an integral and complex role in the economies and ecologies of many
countries across the globe, including those of West and Central Africa, the focus of this
policy perspective. The trade in wild meat, and its role in diets, have been brought into
focus as a consequence of discussions over the origins of COVID-19. As a result, there
have been calls for the closure of Chinaâs âwet marketsâ; greater scrutiny of the wildlife
trade in general; and a spotlight has been placed on the potential risks posed by growing human populations and shrinking natural habitats for animal to human transmission of
zoonotic diseases. However, to date there has been little attention given to what the consequences of the COVID-19 economic shock may be for the wildlife trade; the people who
rely on it for their livelihoods; and the wildlife that is exploited. In this policy perspective,
we argue that the links between the COVID-19 pandemic, rural livelihoods and wildlife
are likely to be more complex, more nuanced, and more far-reaching, than is represented in
the literature to date. We develop a causal model that tracks the likely implications for the
wild meat trade of the systemic crisis triggered by COVID-19. We focus on the resulting
economic shockwave, as manifested in the collapse in global demand for commodities such
as oil, and international tourism services, and what this may mean for local African economies and livelihoods. We trace the shockwave through to the consequences for the use
of, and demand for, wild meats as households respond to these changes. We suggest that
understanding and predicting the complex dynamics of wild meat use requires increased
collaboration between environmental and resource economics and the ecological and conservation sciences
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