Rnf20 deficiency in adipocyte impairs adipose tissue development and thermogenesis

RNF20, an E3 ligase critical for monoubiquitination of histone H2B at lysine 120 (H2Bub), has been implicated in the regulation of various cellar processes; however, its physiological roles in adipocytes remain poorly characterized. Here, we report that the adipocyte-specific knockout of Rnf20 (ASKO) in mice led to progressive fat loss, organomegaly and hyperinsulinemia. Despite signs of hyperinsulinemia, normal insulin sensitivity and improved glucose tolerance were observed in the young and aged CD-fed ASKO mice. In addition, high-fat diet-fed ASKO mice developed severe liver steatosis. Moreover, we observed that the ASKO mice were extremely sensitive to a cold environment due to decreased expression levels of brown adipose tissue (BAT) selective genes, including uncoupling protein 1 (Ucp1), and impaired mitochondrial functions. Significantly decreased levels of peroxisome proliferator-activated receptor gamma (Pparγ) were observed in the gonadal white adipose tissues (gWAT) from the ASKO mice, suggesting that Rnf20 regulates adipogenesis, at least in part, through Pparγ. Rosiglitazone-treated ASKO mice exhibited increased fat mass compared to that of the non-treated ASKO mice. Collectively, our results illustrate the critical role of RNF20 in control of white and brown adipose tissue development and physiological function.

Distribution, drug resistance and drug sensitivity of pathogens in patients with intra-abdominal infection / 安徽医科大学学报

Objective To investigate the distribution of pathogens and the results of drug sensitivity test in patients with intra-abdominal infection, and to provide theoretical basis for the rational selection of anti-infective programs. Methods The pathogenic bacteria culture and drug sensitivity test results of peritoneal fluid or drainage fluid in hospitalized patients with intra-abdominal infection were retrospectively analyzed. Results 405 cases of positive culture results were obtained in 3 509 cases of intra-abdominal infection specimens. A total of 436 strains of pathogens, including 268 strains of Gram-negative bacteria (61.47％), 151 strains of Gram-positive bacteria(34. 63％), 17 strains of Fungi (3. 90％). The top five were Escherichia coli (22. 25％), Acinetobacter baumannii (10. 09％), Klebsiella pneumoniae (9. 86％), Enterococcus faecium (7. 80％), Staphylococcus aureus(4. 13％). The extended spectrum β-lactamas rates of Escherichia coli and Klebsiella pneumoniae were 58. 76％ and 16. 28％, respectively. The multi-drug resistant strains of Acinetobacter baumannii were 79. 55％. Vancomycin resistant strains were detected in Enterococcus faecium (8. 82％), the detection rate of methicillin-resistant Staphylococcus aureus (MRSA) in Staphylococcus aureus was 72. 22％, and the detection rate of methicillin-resistant Staphylococcus aureus (MRCNS) in coagulase-negative Staphylococci was 51. 92％. Conclusion The main pathogens of intra-abdominal infection is Escherichia coli, followed by Acinetobacter baumannii, Klebsiella pneumoniae, Enterococcus faecium and Staphylococcus aureus, the detection rate of MRSA and MRCNS is high. The overall drug resistance of intra-abdominal infection is serious.