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Selenium is an essential trace element and its deficiency was implicated in heart diseases. We recently showed low Se levels in chronic chagasic patients with cardiomyopathy. Herein, mice were depleted in Se by feeding the mothers with chow containing only 0.005 mg Se/kg and maintaining this diet for offspring, that were further infected with Trypanosoma cruzi. Survival rate was significantly lower in Se deficient than in control mice. Parasitemia was similar in all groups. Necrotic heart lesions were found after infection (high CK-MB levels). No outbreaks of parasite growth were detected in chronic survivors submitted or not to a second Se depletion. The present results confirm our hypothesis that a nutritional deficiency in Se is associated to a higher mortality during T. cruzi infection. The potential beneficial effect of Se supplementation is a perspective. Hypothesis to explain the higher susceptibility of Se-depleted mice to T. cruzi infection are discussed.Index Descriptors and Abbreviations: Se, selenium; GPx (EC 1.11.1.9), glutathione peroxidade; CK-MB (EC 2.7.3.2), creatine kinase cardiac isoenzyme; Trypanosoma cruzi; Chagas’ disease. [Copyright &y& Elsevier]

The Caatinga biome, characterized by its dynamic vegetation due to climate and land use changes, experiences varied environmental responses during the dry and rainy seasons. This research aims to dissect the complexity of surface radiation fluxes, vapor pressure, and air and soil temperatures across three distinct vegetation densities within the Caatinga: recovering, degraded, and preserved. Utilizing data from Moderate Resolution Imaging Spectroradiometer/Enhanced Vegetation Index products to analyze these densities offers a novel lens through which to view the biome's reaction to climatic shifts. Our findings unveiled specific patterns of solar and longwave radiation fluxes that correlate with key climatic variables like air temperature and surface albedo. This investigation not only addresses a critical gap in our knowledge of a globally significant but underexplored biome, but it also advances our comprehension of how vegetation density influences radiation fluxes in arid settings. Insights from this study are vital for forecasting and mitigating the ecological and climatic impacts of land cover transformations in semiarid regions worldwide. Significantly, the degraded site displayed nearly double the solar radiation reflection (138 Wm−2) compared to the recovering site (68 Wm−2), underscoring the role of vegetation density in modulating local climate conditions, despite atmospheric consistency across the study sites. [Display omitted] • The Caatinga biome covers the world's most densely populated dry region. • The study observes radiation fluxes over different vegetation densities. • Recovering and degraded vegetation had higher incoming solar radiation. • Preserved Caatinga areas emitted the most intense longwave radiation. • Degraded Caatinga showed the highest surface albedo values. [ABSTRACT FROM AUTHOR]