Microbiota-dependent alteration in innate immune response early on during infection may explain poor outcome in aged host with CDI.

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The widespread availability of energy-dense, rewarding foods is correlated with the increased incidence of obesity across the globe. Overeating during mealtimes and unscheduled snacking disrupts timed metabolic processes, which further contribute to weight gain. The neuronal mechanism by which the consumption of energy-dense food restructures the timing of feeding is poorly understood. Here, we demonstrate that dopaminergic signaling within the suprachiasmatic nucleus (SCN), the central circadian pacemaker, disrupts the timing of feeding, resulting in overconsumption of food. D1 dopamine receptor (Drd1)-null mice are resistant to diet-induced obesity, metabolic disease, and circadian disruption associated with energy-dense diets. Conversely, genetic rescue of Drd1 expression within the SCN restores diet-induced overconsumption, weight gain, and obesogenic symptoms. Access to rewarding food increases SCN dopamine turnover, and elevated Drd1signaling decreases SCN neuronal activity, which we posit disinhibits downstream orexigenic responses. These findings define a connection between the reward and circadian pathways in the regulation of pathological calorie consumption.

On the macroevolutionary time scale, does trait evolution proceed gradually or by rapid bursts (pulses) separated by prolonged periods of stasis or slow evolution? Although studies have shown that pulsed evolution is prevalent in animals, our knowledge about the tempo and mode of evolution across the tree of life is very limited. This long-standing debate calls for a test in bacteria and archaea, the most ancient and diverse forms of life with unique population genetic properties. Using a likelihood-based framework, we show that pulsed evolution is not only present but also prevalent and predominant in microbial genomic trait evolution. We detected two distinct types of pulsed evolution (small frequent and large rare jumps) that are predicted by the punctuated equilibrium and quantum evolution theories. Our findings suggest that major bacterial lineages could have originated in quick bursts and that pulsed evolution is a common theme across the tree of life.

Objective To explore susceptibility loci associated with uveitis in Behçet's disease (BD). Methods We conducted a 2‐stage study, consisting of a genome‐wide association study (GWAS) stage and a replication stage, in a Chinese population. The GWAS stage included 978 cases with BD‐related uveitis and 4,388 controls, and the replication stage included 953 cases with BD‐related uveitis and 2,129 controls. Luciferase reporter analysis and chromatin immunoprecipitation assay were performed to explore the functional role of susceptibility genetic variants near ZMIZ1. Results Three independent HLA alleles (HLA–B51 [3.75 × 10−190], HLA–A26 [1.50 × 10−18], and HLA–C0704 [3.44 × 10−16]) were identified as having a genome‐wide association with BD‐related uveitis. In the non‐HLA region, in addition to confirming 7 previously reported loci, we identified 22 novel susceptibility variants located in 16 loci. Meta‐analysis of the Chinese cohort consisting of 1,931 cases and 6,517 controls and a published Japanese cohort of 611 cases and 737 controls showed genome‐wide significant associations with ZMIZ1, RPS6KA4, IL10RA, SIPA1‐FIBP‐FOSL1, and VAMP1. Functional experiments demonstrated that genetic variants of ZMIZ1 were associated with enhanced transcription activity and increased expression of ZMIZ1. Conclusion This GWAS study identified a novel set of genetic variants that are associated with susceptibility to uveitis in BD. These findings enrich our understanding of the contribution of genetic factors to the disease.