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Oxidative stress, impairment of antioxidant defenses, and disruption of calcium homeostasis are associated with the toxicity of methylmercury (MeHg). Yet, the relative contribution and interdependence of these effects and other molecular mechanisms that mediate MeHg-induced neurotoxicity remain uncertain. The signal transducer and activator of transcription 3 (STAT3) is a transcription factor that regulates the expression of anti-apoptotic and cell cycle progression genes. In addition to its role in cell growth and survival, STAT3 regulates redox homeostasis and prevents oxidative stress by the modulation of nuclear genes that encode for electron transport complexes (ETC) and antioxidant enzymes. Here we tested the hypothesis that STAT3 contributes to the orchestration of the antioxidant defense response against MeHg injury. We show that MeHg (>1 μM) exposure induced STAT3 activation within 1 h and beyond in mouse hypothalamic neuronal GT1-7 cells in a concentration-and time-dependent manner. Pharmacological inhibition of STAT3 phosphorylation exacerbated MeHg-induced reactive oxygen species (ROS) production and antioxidant responses. Finally, treatment with the antioxidant Trolox demonstrated that MeHg-induced STAT3 activation is mediated, at least in part, by MeHg-induced ROS generation. Combined, our results demonstrated a role for the STAT3 signaling pathway as an early response to MeHg-induced oxidative stress.Ferroptosis was first described in 2012 as an iron- and lipid peroxidation-dependent form of regulated cell death. Since its initial description, these two characteristics have informed numerous cell culture studies where inhibitors of lipid peroxidation and/or iron chelators have been shown to prevent cell death induced by a wide range of insults. However, it is not clear whether these two characteristics are sufficient to distinguish ferroptosis from other forms of regulated cell death. Thus, the primary goal of this study was to determine whether a unique combination of features could be identified that would provide an approach to more clearly separate ferroptosis from other forms of regulated cell death. To this end, multiple pharmacological inhibitors based on a variety of studies were tested. Many of these inhibitors were previously shown to protect cells from oxytosis, a regulated cell death pathway that mechanistically overlaps with ferroptosis and is induced by some of the same chemicals as ferroptosis. These inhibitors were not only tested against both known ferroptosis and oxytosis inducers but also a number of other insults that have been suggested to induce ferroptosis. The results show that a pharmacological fingerprint for ferroptosis can be established and used to categorize toxic insults into those that overlap with oxytosis/ferroptosis and those that do not.

The epidemiology of atrial fibrillation (AF) in India has not been studied systematically in large scale population based surveys. Pimasertib MEK inhibitor Stroke is one of the leading causes of death and disability in India. As AF is a major contributor of stroke, it is important to know the burden of AF and stroke risk in the population. The Andhra Pradesh Atrial Fibrillation (AP-AF) study aims to assess the prevalence, etiology, risk factors and stroke risk among the rural population in Andhra Pradesh, India.

This is a cross-sectional survey done using a two-stage sampling process. Adults (≥18years) from villages in East and West Godavari districts were sampled. Field investigators used a structured questionnaire to collect information on basic demographics, cardiovascular risk factors and medical history. Anthropometric measurements were performed, blood pressure measured and fasting capillary blood glucose was assessed. Electrocardiogram was done using a hand-held mobile ECG device-KardioMobile. ECGs were interpreted by study cardiologists. Participants diagnosed to have AF were invited to participate in a camp conducted by cardiologists where echocardiogram was done and also a focused history related to AF was collected. Along with age and sex stratified prevalence of AF, descriptive statistics will be used to present demographics, clinical profile, and cardiovascular risk factors. Stroke risk will be calculated using CHA 2 DS 2 -Vasc score.

The AP-AF study is expected to provide important information on AF epidemiology in rural India. The information may help improve health care policies in preventing stroke and other complications of AF.

The AP-AF study is expected to provide important information on AF epidemiology in rural India. The information may help improve health care policies in preventing stroke and other complications of AF.An effective response to the ongoing coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) will involve a range of complementary preventive modalities. The current studies were conducted to evaluate the in vitro SARS-CoV-2 antiviral and virucidal (irreversible) activity of astodrimer sodium, a dendrimer with broad spectrum antimicrobial activity, including against enveloped viruses in in vitro and in vivo models, that is marketed for antiviral and antibacterial applications. We report that astodrimer sodium inhibits replication of SARS-CoV-2 in Vero E6 and Calu-3 cells, with 50% effective concentrations (EC50) for i) reducing virus-induced cytopathic effect of 0.002-0.012 mg/mL in Vero E6 cells, and ii) infectious virus release by plaque assay of 0.019-0.032 mg/mL in Vero E6 cells and 0.030-0.037 mg/mL in Calu-3 cells. The selectivity index (SI) in these assays was as high as 2197. Astodrimer sodium was also virucidal, irreversibly reducing SARS-CoV-2 infectivity by >99.9% (>3 log10) within 1 min of exposure, and up to >99.999% (>5 log10) shown at astodrimer sodium concentrations of 10-30 mg/mL in Vero E6 and Calu-3 cell lines. Astodrimer sodium also inhibited infection in a primary human airway epithelial cell line. The data were similar for all investigations and were consistent with the potent antiviral and virucidal activity of astodrimer sodium being due to irreversible inhibition of virus-host cell interactions, as previously demonstrated for other viruses. Further studies will confirm if astodrimer sodium binds to SARS-CoV-2 spike protein and physically blocks initial attachment of the virus to the host cell. Given the in vitro effectiveness and significantly high SI, astodrimer sodium warrants further investigation for potential as a topically administered agent for SARS-CoV-2 therapeutic applications.