Change in the activity of glucosylceramide synthase in human hepatoma cell line with hepatitis B virus infection in vitro / 临床肝胆病杂志

ObjectiveTo investigate the change in the activity of glucosylceramide synthase, the key enzyme in glycosphingolipid metabolism and synthesis, in Huh7 cells infected by hepatitis B virus (HBV) in vitro. MethodsBlood samples were collected from nine previously untreated patients with acute hepatitis B who attended Department of Infectious Diseases, The First Hospital of Lanzhou University, from June to August, 2019, and the blood samples collected from seven healthy individuals who underwent physical examination were established as control. Huh7 cells were inoculated with the high-copy HBV particles (＞9.9×107 IU/ml) in the serum of patients with HBV infection (infection group), and Huh7 cells co-cultured with the serum of healthy individuals were established as control group. The expression levels of HBsAg and HBV DNA in the cytoplasm of HBV-infected Huh7 cells were measured, and the correlation between GCS activity and virus was analyzed. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t-test was used for further comparison between two groups, and a Pearson correlation analysis was performed. ResultsCompared with the control group, the infection group had a significant reduction in the number of cells, an increase in cell volume, and cell membrane fragmentation. The infection group had a significant increase in the expression of HBsAg in cytoplasm at 4 hours, 8 hours, 2 days, and 5 days after infection (P＜0.05); the expression level of HBV DNA tended to increase significantly from 4 hours after infection to 8 hours, 2 days, and 5 days after infection (16.67±11.55 IU/ml vs 112.01±25.94 IU/ml/328.01±10350 IU/ml/101.60±49.84 IU/ml, P＜0.001), with the highest level at 2 days after infection. During HBV infection, the activity of GCS gradually increased with the increase in viral replication from 4 hours after infection (126.21±9.59 IU/ml) and reached a peak at 2 days after infection (226.53±36.27 IU/ml), with a significant difference between the infection group and the control group at 2 days after infection (226.53±36.27 IU/ml vs 136.50±1544 IU/ml, t=3.956, P=0.016 7). The activity of GCS was positively correlated with HBV DNA level (r=0.576 8, P=0047 1). ConclusionHuh7 cells are successfully infected with the high-copy HBV particles in the serum of patients with HBV infection, which mimics the characteristics of HBV infection in vitro to a certain degree. The activity of GCS may be associated with HBV infection, suggesting that glycosphingolipid synthesis and metabolism may be closely associated with HBV.

Clinical analysis of sepsis with extensively drug resistant Gram-negative bacteria in intensive care unit treated with polymyxin B-based combination therapy / 中华危重病急救医学

Objective:To investigate the clinical efficacy and safety of polymyxin B in the treatment of sepsis caused by extensively-drug resistant (XDR) Gram-negative bacteria.Methods:A retrospective analysis of 39 septic patients with XDR Gram-negative bacterial infection treated with polymyxin B in the department of critical care medicine of Xiangya Hospital of Central South University from June 2018 to September 2019 were enrolled. The clinical characteristics, bacterial culture, the sensitivity antibacterial drugs, types and courses of antibiotics, biochemical indexes, and acute physiology and chronic health evaluationⅡ(APACHEⅡ) before and after polymyxin B treatment were collected, to assess microbial clearance and efficacy, drug related adverse effects, and 28-day mortality in septic patients with XDR.Results:Of the 39 septic patients with XDR, 32 (82.1%) were male, with the mean age of (53.6±12.6) years old. The main infection site was pulmonary infection (51.2%), and the treatment courses of polymyxin B were ≥ 5 days. A total of 66 pathogenic bacteria were detected from 39 patients. Among them, with the high estrate of detecting Acinetobacter baumannii of 51.5% (34/66). After treatment with polymyxin B, the results showed that the clearance rate of microorganisms was 65.2% (43/66), the overall effective rate was 59.0% (23/39), and the 28-day all-cause mortality was 41.0% (16/39). There were no significant differences in clinical efficacy and microbial clearance among patients with different treatment groups of polymyxin B [< 10 days, 10-15 days, and > 15 days groups: effective rates were 56.5% (13/23), 54.5% (6/11), 80.0% (4/5), χ2 = 0.999, P = 0.728; the microbial clearance rates were 43.5% (10/23), 54.5% (6/11), and 80.0% (4/5), χ2 = 2.141, P = 0.393]. The effective and microbial clearance rates of the polymyxin B daily doses of 150 mg and 200 mg groups were significantly higher than those of the daily dose of 100 mg [effectiveness: 85.7% (6/7), 87.5% (7/8) vs. 41.7% (10/24); microbial clearance rate: 71.4% (5/7), 87.5% (7/8) vs. 33.3% (8/24), all P < 0.05], however, there were no significant differences in the length of intensive care unit (ICU) stay and mechanical ventilation time among different daily dose groups. The APACHEⅡscore after polymyxin B administration was significantly lower than before administration (all patients: 16.20±9.24 vs. 24.40±4.73, effective patients: 11.30±4.08 vs. 23.00±4.56, both P < 0.05). Four patients with renal injury had an increase in serum creatinine during the administration of polymyxin B, and recovered after discontinuation of the drug without other adverse reactions. Conclusion:Polymyxin B can be used as an effective treatment option for patients with severe infection of XDR Gram-negative bacteria.

Relationship between bile acid metabolism and chronic non - cholestatic liver disease / 中华肝脏病杂志

Bile acid is a general term for a large class of cholic acid in bile and exerts its unique physiological functions by binding the relevant receptors and bile acid transporters. Bile acids not only promote the absorption of nutrients in the human body, but also as an important signaling molecule in the regulation of inflammatory processes and liver regeneration. Several studies have found that bile acid metabolism is involved in the occurrence and development of chronic non-cholestatic liver diseases. In this article, the latest research results are mentioned, and the relationship between nuclear receptors, membrane receptors, and bile acid transporters and chronic non-cholestatic liver disease that play a key role in the bile acid metabolism were emphatically reviewed.