Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.

Objective:To study the risk factors and the molecular epidemiology characteristics for Carbapenem-resistant Enterobacteriaceae(CRE) colonization in neonatal inpatients in Shenzhen region, China, which provide reference for the prevention and control of clinical CRE infection.Methods:This study is a prospective case-control study.Anal samples from inpatients between January 2023 and December 2023 at Longgang Maternity and Child Institute of Shantou University Medical College and Shenzhen Children's Hospital were collected for screening CRE strain. Drug susceptibility test, modified Carbapenem Inactivation Method (mCIM) test, drug resistance-related gene sequencing and multilocus sequence typing (MLST) were performed for isolated CRE strains.Meanwhile, the clinical data were collected for analyzing the risk factors of CRE intestinal colonization by multivariate regression analysis.Results:A total of 1 517 patients were screened, 26 CRE(1.7%, 26/1 517) were identified which including 14 Escherichia coli(53.8%, 14/26), 11 Klebsiella pneumoniae(42.3%, 11/26), 1 Enterobacter cloacae(3.9%, 1/26). The predominant carbapenemase gene was New Delhi Metallo(NDM) (92.4%, 24/26), followed by Imipenem (IMP) (3.8%, 1/26) and Guiana extended spectrum gene (GES) (3.8%, 1/26).Among the carried NDM resistance genes, New Delhi Metallo 5 (NDM5) was the main one, accounting for 84.6% (22/26).The MLST typing of Escherichia coli was mainly Sequence Type 48 (ST48) (6/14), while that of Klebsiella pneumoniae was mainly Sequence Type 35 (ST35) (10/11). All CRE isolates were resistant to penicillin, penicillinase inhibitors, cephalosporins, ertapenem and imipenem.The resistance rates of Escherichia coli to amikacin, levofloxacin was 1/14, 4/14, respectively. All isolates of Klebsiella pneumoniae were sensitive to amikacin, and the resistance rate to levofloxacin is 1/11. Risk factors for CRE colonization include the older age, length of hospital stay, tracheal intubation, invasive respiration, lumbar puncture, Apgar <7 score, and exposure to antibiotics.Conclusions:NDM5 is the predominant resistant gene in CRE isolated from neonatal patients feces in Shenzhen region.It is necessary to strengthen the screening of CRE colonization in neonate for prevention and control of CRE infection.

A stable HMG-CoA reductase (HMGR) reaction in vitro was developed by a sensitive, selective and precise liquid chromatography–tandem mass spectrometry (LC–MS/MS) method. The optimized enzyme reac-tion condition contained 1.5μg of HMGR, 20 nM of NADPH with 50 min of reaction time. The method was validated by several intra-and inter-day assays. The production transitions of m/z 147.0/59.1 and m/z 154.0/59.1 were used to detect and quantify mevalonolactone (MVAL) and MVAL-D7, respectively. The accuracy and precision of the method were evaluated over the concentration range of 0.005–1.000μg/mL for MVAL and 0.010–0.500μg/mL for lovastatin acid in three validation batch runs. The lower limit of quantitation was found to be 0.005μg/mL for MVAL and 0.010μg/mL for lovastatin acid. Intra-day and inter-day precision ranged from 0.95%to 2.39%and 2.26%to 3.38%for MVAL, 1.46%to 3.89%and 0.57% to 5.10% for lovastatin acid, respectively. The results showed that the active ingredients in Xuezhikang capsules were 12.2 and 14.5 mg/g, respectively. This assay method could be successfully applied to the quality control study of Xuezhikang capsule for the first time.

Xuezhikang capsule (ethanol extract of red yeast rice) which produced by Beijing WBL Peking University Biotech Co., Ltd., is a traditional Chinese medication with 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibiting activity. Clinical trials indicated that Xuezhikang with lipid-lowering action could reduce the risk of cardiac events and total mortality of Chinese coronary heart disease patients. To exactly explain the clinical features of Xuezhikang, we undertook a complete study of the chemical constituents of Xuezhikang. This study resulted in the isolation of a new monacolin analogue, named alpha, beta-dehydromonacolin L (1), along with two known compounds: monacolin L (2) and 3-(2, 6-dimethyl-1, 2, 4a, 5, 6, 7, 8, 8a-octahydronaphthalen-1-yl)propanoic acid (3). The chemical structures were determined by extensive 1D and 2D NMR and MS spectroscopic analysis.

The residents who had lived for at least 5 years and aged over 20 years old were sampled from urban to rural districts of Jiangsu Province with a stratified cluster sampling technique. B mode ultrasonography and thyroid function determination were carried out in 6 128 persons. The location, diameter, number, boundary, and calcification in thyroid nodules were described by using 7.5 MHz/50 mm transducer of thyroid ultrasonography. TSH was measured by chemiluminescence immunoassay. Free triiodothyronine(FT3)and free thyroxin(FT4)were measured when TSH was abnormal. The crude prevalence of thyroid nodules was 21.12% in total population, 14.55% in male, and 25.24% in female. The standardized prevalence was 15.69%, 11.20%, and 20.40%, respectively. The prevalence was lower in male than in female, and increased with age(P＜0.05). Thyroid nodules in Jiangsu Province were highly prevalent and more attention should be paid to the follow-up, early diagnosis, and treatment.