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IMPORTANCE Local variation in the transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) across the United States has not been well studied. OBJECTIVE To examine the association of county-level factors with variation in the SARS-CoV-2 reproduction number over time.

Exposure to general anesthesia before 3 years of age was not associated with ADHD.

Epigenetic changes might provide the biological explanation for the long-lasting impact of metabolic alterations of diabetic kidney disease development. Here we examined cytosine methylation of human kidney tubules using Illumina Infinium 450 K arrays from 91 subjects with and without diabetes and varying degrees of kidney disease using a cross-sectional design. We identify cytosine methylation changes associated with kidney structural damage and build a model for kidney function decline. We find that the methylation levels of 65 probes are associated with the degree of kidney fibrosis at genome wide significance. In total 471 probes improve the model for kidney function decline. Methylation probes associated with kidney damage and functional decline enrich on kidney regulatory regions and associate with gene expression changes, including epidermal growth factor ( EGF ). Altogether, our work shows that kidney methylation differences can be detected in patients with diabetic kidney disease and improve kidney function decline models indicating that they are potentially functionally important.

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Diabetic nephropathy accounts for most of the excess mortality in individuals with diabetes, but the molecular mechanisms by which nephropathy develops are largely unknown. Here we tested cytosine methylation levels at 397,063 genomic CpG sites for association with decline in the estimated glomerular filtration rate (eGFR) over a six year period in 181 diabetic Pima Indians. Methylation levels at 77 sites showed significant association with eGFR decline after correction for multiple comparisons. A model including methylation level at two probes (cg25799291 and cg22253401) improved prediction of eGFR decline in addition to baseline eGFR and the albumin to creatinine ratio with the percent of variance explained significantly improving from 23.1% to 42.2%. Cg22253401 was also significantly associated with eGFR decline in a case-control study derived from the Chronic Renal Insufficiency Cohort. Probes at which methylation significantly associated with eGFR decline were localized to gene regulatory regions and enriched for genes with metabolic functions and apoptosis. Three of the 77 probes that were associated with eGFR decline in blood samples showed directionally consistent and significant association with fibrosis in microdissected human kidney tissue, after correction for multiple comparisons. Thus, cytosine methylation levels may provide biomarkers of disease progression in diabetic nephropathy and epigenetic variations contribute to the development of diabetic kidney disease.

Liver X receptors (LXRs) are nuclear receptors involved in the regulation of lipid metabolism and inflammatory responses in the central nervous system. Defects in cholesterol homeostasis contribute to the pathogenesis of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, multiple sclerosis, and Huntington's disease. Inflammatory responses could enhance the neurodegenerative process or act independently. The natural and synthetic LXR agonists induce the transcriptional activity of LXR target genes, thus attenuate the imbalance of cholesterol metabolism and overactivation of microglia and astrocytes in inflammation and are widely used in a variety of neurodegenerative diseases animal models. By developing more specific, potent, penetrable, and functional LXR agonist may lead to a better curative effect for neurodegenerative diseases and avoidance of potentially deleterious side effects. Here, we focus on recent advances in our understanding of the role of LXRs and their agonists in cholesterol homeostasis, inflammation, and the potential therapeutic effects in neurodegenerative diseases.

Propofol is currently one of the most widely used intravenous anesthetics and has been indicated to induce cognitive dysfunction in adults. Here, we investigated the effects of propofol exposure during early postnatal life on hippocampal neurogenesis. Propofol (30 or 60 mg/kg) was administered to mice on either postnatal day (P) 7 or P7-P9; cell proliferation and neurogenesis in the dentate gyrus (DG) were evaluated on P8 or P17. It showed that exposure to propofol on P7 decreased hippocampal cell proliferation as indicated by BrdU and Sox2 immunostaining at P8 in propofol treatment at the dosage of 60 mg/kg but not at the dosage of 30 mg/kg. Western blots revealed propofol treatment decreased Akt or extracellular signal-related kinase (ERK) 1/2 phosphorylation in the hippocampus at P8. Propofol treatment on P7 to P9 reduced the numbers of newly formed neurons in the DG at P17, which was accompanied by delay of granule neuron maturation and decreased the density of dendritic spines, particularly the mushroom-shaped mature spines. Furthermore, the in vitro findings indicated propofol suppressed cell proliferation and cell mitosis and activated apoptosis of C17.2 neural stem cell line in a dose-dependent manner. These findings suggest that propofol impairs cell proliferation and inhibits neurogenesis in the immature mouse brain and thus is possibly involved in the cognitive dysfunction induced by propofol anesthesia.