Analysis of distribution characteristics and drug resistance of pathogens isolated from ascites of patients in Children's Hospital Affiliated to Zhengzhou University, 2015-2021 / 中国热带医学

@#Abstract: Objective　To investigate the distribution and drug resistance of pathogenic bacteria separated from ascites of patients in Children’s Hospital Affiliated to Zhengzhou University from 2015 to 2021, and to provide a basis for rational clinical antimicrobial agents. Methods　Bacterial culture, bacterial identification and drug sensitivity analysis were performed on 1 058 non-duplicate ascites culture specimens from January 2015 to December 2021. The clinica1 and microbiologica1 data were ana1yzed by WHONET 5.6 and SAS 9.4 Results　Of the 1 058 specimens, 586 (55.39%) were positive for pathogenic bacteria, with a total of 781 strains isolated. There was no significant trend of increase or decrease in the positivity rate over different years. Male children (63.99%) were more prevalent than female children. Appendicitis (59.22%) was the most common disease and Escherichia coli was the most common causative bacteria. Among neonates (≤28 d), the bacteria with the highest detection rate were Klebsiella pneumoniae (23.50%) and Enterococcus faecium (23.50%), while among children (>28 d), the highest detection rate was Escherichia coli (35.98%). Gram-negative bacteria accounted for 64.79% of the 781 strains, mainly Escherichia coli (38.28%), Klebsiella pneumoniae (8.58%), and Pseudomonas aeruginosa (5.89%); Gram-positive bacteria accounted for 29.45%, mainly Enterococcus faecium (8.58%), Streptococcus constellatus (2.69%), and Enterococcus avium (2.43%); fungi accounted for 1.66% and anaerobic bacteria accounted for 4.10%. The resistance rates of Escherichia coli to cefoperazone/sulbactam, piperacillin/tazobactam, imipenem and meropenem were 6.02%, 4.35%, 4.35%, and 3.68%, respectively. The resistance rates of Klebsiella pneumoniae to these drugs were 59.70%, 59.70%, 50.75% and 53.73% respectively. Linezolid-resistant strains of Enterococcus faecium were found. Conclusion　Appendicitis is the most common abdominal infection in children, and the distribution of ascites pathogens varies with ages and diseases. The pathogenic bacteria are mainly Gram-negative bacteria, and the drug resistance of Klebsiella pneumoniae was more serious. It is particularly important to use antibiotics correctly and rationally to reduce the emergence of drug resistant bacteria.

Rapid Increase in Prevalence of Carbapenem-Resistant Enterobacteriaceae (CRE) and Emergence of Colistin Resistance Gene mcr-1 in CRE in a Hospital in Henan, China.

The global spread of carbapenem-resistant Enterobacteriaceae (CRE) is one of the most severe threats to human health in a clinical setting. The recent emergence of plasmid-mediated colistin resistance gene mcr-1 among CRE strains greatly compromises the use of colistin as a last resort for the treatment of infections caused by CRE. This study aimed to understand the current epidemiological trends and characteristics of CRE from a large hospital in Henan, the most populous province in China. From 2014 to 2016, a total of 7,249 Enterobacteriaceae isolates were collected from clinical samples, among which 18.1% (1,311/7,249) were carbapenem resistant. Carbapenem-resistant Klebsiella pneumoniae and carbapenem-resistant Escherichia coli were the two most common CRE species, with Klebsiella pneumoniae carbapenemases (KPC) and New Delhi metallo-ß-lactamases (NDM), respectively, responsible for the carbapenem resistance of the two species. Notably, >57.0% (n = 589) of the K. pneumoniae isolates from the intensive care unit were carbapenem resistant. Furthermore, blaNDM-5 and mcr-1 were found to coexist in one E. coli isolate, which exhibited resistance to almost all tested antibiotics. Overall, we observed a significant increase in the prevalence of CRE isolates during the study period and suggest that carbapenems may no longer be considered to be an effective treatment for infections caused by K. pneumoniae in the studied hospital.

Lactobacillus species shift in distal esophagus of high-fat-diet-fed rats.

AIM: To analyze the microbiota shift in the distal esophagus of Sprague-Dawley rats fed a high-fat diet. METHODS: Twenty Sprague-Dawley rats were divided into high-fat diet and normal control groups of 10 rats each. The composition of microbiota in the mucosa from the distal esophagus was analyzed based on selective culture. A variety of Lactobacillus species were identified by molecular biological techniques. Bacterial DNA from Lactobacillus colonies was extracted, and 16S rDNA was amplified by PCR using bacterial universal primers. The amplified 16S rDNA products were separated by denaturing gradient gel electrophoresis (DGGE). Every single band was purified from the gel and sent to be sequenced. RESULTS: Based on mucosal bacterial culturing in the distal esophagus, Staphylococcus aureus was absent, and total anaerobes and Lactobacillus species were decreased significantly in the high-fat diet group compared with the normal control group (P < 0.01). Detailed DGGE analysis on the composition of Lactobacillus species in the distal esophagus revealed that Lactobacillus crispatus, Lactobacillus gasseri (L. gasseri) and Lactobacillus reuteri (L. reuteri) comprised the Lactobacillus species in the high-fat diet group, while the composition of Lactobacillus species in the normal control group consisted of L. gasseri, Lactobacillus jensenii and L. reuteri. CONCLUSION: High-fat diet led to a mucosal microflora shift in the distal esophagus in rats, especially the composition of Lactobacillus species.

Effects of two Lactobacillus strains on lipid metabolism and intestinal microflora in rats fed a high-cholesterol diet.

BACKGROUND: The hypocholesterolemic effects of lactic acid bacteria (LAB) have now become an area of great interest and controversy for many scientists. In this study, we evaluated the effects of Lactobacillus plantarum 9-41-A and Lactobacillus fermentum M1-16 on body weight, lipid metabolism and intestinal microflora of rats fed a high-cholesterol diet. METHODS: Forty rats were assigned to four groups and fed either a normal or a high-cholesterol diet. The LAB-treated groups received the high-cholesterol diet supplemented with Lactobacillus plantarum 9-41-A or Lactobacillus fermentum M1-16. The rats were sacrificed after a 6-week feeding period. Body weights, visceral organ and fat pad weights, serum and liver cholesterol and lipid levels, and fecal cholesterol and bile acid concentrations were measured. Liver lipid deposition and adipocyte size were evaluated histologically. RESULTS: Compared with rats fed a high-cholesterol diet but without LAB supplementation, serum total cholesterol, low-density lipoprotein cholesterol and triglycerides levels were significantly decreased in LAB-treated rats (p < 0.05), with no significant change in high-density lipoprotein cholesterol levels. Hepatic cholesterol and triglyceride levels and liver lipid deposition were significantly decreased in the LAB-treated groups (p < 0.05). Accordingly, both fecal cholesterol and bile acids levels were significantly increased after LAB administration (p < 0.05). Intestinal Lactobacillus and Bifidobacterium colonies were increased while Escherichia coli colonies were decreased in the LAB-treated groups. Fecal water content was higher in the LAB-treated groups. Compared with rats fed a high-cholesterol diet, administration of Lactobacillus plantarum 9-41-A resulted in decreases in the body weight gain, liver and fat pad weight, and adipocytes size (p < 0.05). CONCLUSIONS: This study suggests that LAB supplementation has hypocholesterolemic effects in rats fed a high-cholesterol diet. The ability to lower serum cholesterol varies among LAB strains. Our strains might be able to improve the intestinal microbial balance and potentially improve intestinal transit time. Although the mechanism is largely unknown, L. plantarum 9-41-A may play a role in fat metabolism.

GPC3 fused to an alpha epitope of HBsAg acts as an immune target against hepatocellular carcinoma associated with hepatitis B virus.

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) in China is closely related to the population infected with hepatitis B virus (HBV). HCC cells with HBV secrete soluble HBsAg into blood but do not express it on the cell membrane. This study aimed to construct and investigate a new glycosyl-phosphatidylinositol (GPI)-anchored protein (GPC3+alpha+EGFP) as a DNA vaccine against HCC associated with HBV. METHODS: A recombinant plasmid (pcDNA3.1(+)/GPC3+ alpha+EGFP) was constructed and verified by restriction endonuclease digestion and sequencing. pcDNA3.1(+)/GPC3+alpha+EGFP was transfected into HepG2 cells (experimental group) using lipofectamine 2000. pEGFP-N1-transfected HepG2 cells were used as a negative control, and non-transfected HepG2 cells served as a blank control. HepG2 cells that steadily expressed the fusion protein GPC3+alpha+EGFP were screened by G418, propagated, and co-cultured with lymphocytes from healthy donors. Cell proliferation was measured by the classic sulforhodamine B assay. Apoptosis was assessed by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL), and Fas gene transcription was determined by quantitative fluorescent PCR. RESULTS: The pcDNA3.1(+)/GPC3+alpha+EGFP plasmid was successfully constructed. In the experimental group, green fluorescence was observed at the cell periphery and in the cytoplasm, whereas in the negative control group, fluorescence was evenly distributed throughout the cell. Proliferation of the experimental group significantly decreased after 72 hours compared to the negative and blank control groups. Furthermore, the number of apoptotic cells was statistically different among the three groups as determined by a contingency table Chi-square test; the experimental group had the highest incidence of apoptosis. Fas gene transcription in the experimental group was higher than in the two control groups, and an increasing trend with time in the experimental group was observed. CONCLUSION: A chimeric, membrane-anchored protein, GPC3+alpha+EGFP, localized to the membrane of HepG2 cells and inhibited proliferation and accelerated apoptosis through a Fas-FasL pathway after co-cultivation with lymphocytes.