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Antimicrobial resistance poses a significant threat to global public health, especially for Enterobacterales. In this study, we investigated the distribution and antimicrobial resistance of Enterobacterales in children in the China Antimicrobial Surveillance Network (CHINET) in 2015–2021. In total, 81,681 strains isolated from children were collected in this period, accounting for 50.1% of Gram-negative organisms. The most frequently isolated Enterobacterales were Escherichia coli, Klebsiella spp., Salmonella spp., and Enterobacter spp. The main sources of the isolates were urine and the respiratory tract, accounting for 29.3% and 27.7% of isolates, respectively. The proportions of E. coli, Klebsiella pneumoniae, and Proteus mirabilis expressing extended-spectrum β-lactamase were 48.8%–57.6%, 49.3%–66.7%, and 23.1%–33.8%, respectively. The prevalence of carbapenem-resistant Enterobacterales was 5.7%–9.5%, which showed a decreasing trend from 2015 to 2021. The detection rates of carbapenem-resistant Klebsiella spp., carbapenem-resistant Enterobacter spp., and carbapenem-resistant E. coli were 14.1%–22.6%, 7.1%–15.7% and 2.0%–3.4%, respectively. In Enterobacterales, the resistance rates to ciprofloxacin were higher than to levofloxacin. However, the Enterobacterales strains were highly susceptible to amikacin, polymyxin B, and tigecycline. The resistance rate of Salmonella spp. to ampicillin was > 70%, whereas their resistance rate to ceftriaxone was < 30%. These findings indicate that the resistant rates of some Enterobacterales isolates in children to common antimicrobial agents show decreasing trends. Continuous monitoring of bacterial resistance should be strengthened to prevent and control the spread of drug-resistant bacteria. [ABSTRACT FROM AUTHOR]

Urinary tract infections (UTIs) are common urological diseases that easily relapse and have led to an increasing economic and health burdens. The China Antimicrobial Surveillance Network (CHINET) system is one of the most influential antimicrobial resistance surveillance networks in China. This study analyzed antimicrobial resistance and distribution trends of uropathogens from 2015 to 2021 using the CHINET system. A total of 261,893 non-duplicate strains were collected; Gram-positive bacteria accounted for 23.8% while Gram-negative bacteria accounted for 76.2%. Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, and Enterococcus faecalis were the most common species. The resistance to vancomycin, linezolid, and teicoplanin in E. faecalis and E. faecium was less than 3%. The prevalence of carbapenem-resistant strains of E. coli, K. pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii was 1.7%, 18.5%, 16.4%, and 40.3%, respectively. The prevalence of carbapenem-resistant A. baumannii increased from 27.6% in 2015 to 43.4% in 2021. The prevalence of methicillin-resistant Staphylococcus aureus decreased from 40.6% in 2015 to 22.9% in 2021. The resistance rates to most β-lactam antimicrobials, aminoglycosides and fluoroquinolones in E. coli, K. pneumoniae, P. aeruginosa and A. baumannii isolated from ICU inpatients were significantly higher than in those isolated from outpatients and non-ICU inpatients. This study indicates that E. coli, Enterococcus, and K. pneumoniae were the most commonly isolated uropathogens in China. The bacterial species isolated and their antimicrobial resistance patterns differed in different patient populations. More attention must be paid uropathogen resistance surveillance to provide data for the rational use of antimicrobial agents. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance poses a global threat to human health. Analyzing monitoring data on antimicrobial resistance can assist clinicians in making strategic decisions and promptly identifying outbreaks of antimicrobial-resistant organisms. The China Antimicrobial Surveillance Network (CHINET) was established in 2004 to monitor the trends in bacterial epidemiology and antimicrobial resistance. In this study, we analyzed the distribution and changing antimicrobial resistance profiles of Enterobacter spp. isolated from 53 hospitals across China between 2015 and 2021 using the CHINET data. Over the seven-year period, a total of 37,966 clinical isolates of Enterobacter spp. were obtained, accounted for 2.5% of all isolates and 5.7% of Enterobacteriaceae isolates. Among those isolates, Enterobacter cloacae was the most prevalent, comprising 93.7% (35,571/37,966). The majority of strains were isolated from respiratory tract samples (44.6%), followed by secretion, pus (16.4%), and urine samples (16.0%). As for patient composition, 37,966 Enterobacter spp. strains were predominantly isolated from inpatients (92.9%), whereas 7.1% were isolated from outpatients and emergency patients. Among inpatients, isolates from patients in surgical ward accounted for the highest percentage (24.4%). E. cloacae exhibited the lowest rates of resistance to amikacin, tigecycline, polymyxin B, imipenem, and meropenem (resistance rates < 8%). However, the percentage of carbapenem-resistant Enterobacter spp. was 10.0%, presenting a rising tendency over the 7-year study period. Antimicrobial resistance profiles of Enterobacter spp. isolates varied according to the department of isolation and patient age (adult or child), with the intensive care unit having the highest proportion of carbapenem-resistant Enterobacter spp. isolates. [ABSTRACT FROM AUTHOR]

Background: To evaluate in vitro susceptibilities of aerobic and facultative Gram-negative bacterial (GNB) isolates from intra-abdominal infections (IAIs) to 12 selected antimicrobials in Chinese hospitals from 2012 to 2014., Methods: Hospital acquired (HA) and community acquired (CA) IAIs were collected from 21 centers in 16 Chinese cities. Extended spectrum beta-lactamase (ESBL) status and antimicrobial susceptibilities were determined at a central laboratory using CLSI broth microdilution and interpretive standards., Results: From all isolated strains the Enterobacteriaceae (81.1%) Escherichia coli accounted for 45.4% and Klebsiella pneumoniae for 20.1%, followed by Enterobacter cloacae (5.2%), Proteus mirabilis (2.1%), Citrobacter freundii (1.8%), Enterobacter aerogenes (1.8%), Klebsiella oxytoca (1.4%), Morganella morganii (1.2%), Serratia marcescens (0.7%), Citrobacter koseri (0.3%), Proteus vulgaris (0.3%) and others (1.0%). Non- Enterobacteriaceae (18.9%) included Pseudomonas aeruginosa (9.8%), Acinetobacter baumannii (6.7%), Stenotrophomonas maltophilia (0.9%), Aeromonas hydrophila (0.4%) and others (1.1%). ESBL-screen positive Escherichia coli isolates (ESBL+) showed a decreasing trend from 67.5% in 2012 to 58.9% in 2014 of all Escherichia coli isolates and the percentage of ESBL+ Klebsiella pneumoniae isolates also decreased from 2012 through 2014 (40.4% to 26.6%), which was due to reduced percentages of ESBL+ isolates in HA IAIs for both bacteria. The overall susceptibilities of all 5160 IAI isolates were 87.53% to amikacin (AMK), 78.12% to piperacillin-tazobactam (TZP) 81.41% to imipenem (IMP) and 73.12% to ertapenem (ETP). The susceptibility of ESBL-screen positive Escherichia coli strains was 96.77%-98.8% to IPM, 91.26%-93.16% to ETP, 89.48%-92.75% to AMK and 84.86%-89.34% to TZP, while ESBL-screen positive Klebsiella pneumoniae strains were 70.56%-80.15% susceptible to ETP, 80.0%-87.5% to IPM, 83.82%-87.06% to AMK and 63.53%-68.38% to TZP within the three year study. Susceptibilities to all cephalosporins and fluoroquinolones were less than 50% beside 66.5% and 56.07% to cefoxitin (FOX) for ESBL+ Escherichia coli and Klebsiella pneumoniae strains respectively., Conclusions: The total ESBL+ rates decreased in Escherichia coli and Klebsiella pneumoniae IAI isolates due to fewer prevalence in HA infections. IPM, ETP and AMK were the most effective antimicrobials against ESBL+ Escherichia coli and Klebsiella pneumoniae IAI isolates in 2012-2014 and a change of fluoroquinolone regimens for Chinese IAIs is recommended.

Background: Trehalose-6-phosphate synthase (TPS) serves important functions in plant desiccation tolerance and response to environmental stimuli. At present, a comprehensive analysis, i.e. functional classification, molecular evolution, and expression patterns of this gene family are still lacking in Solanum tuberosum (potato)., Results: In this study, a comprehensive analysis of the TPS gene family was conducted in potato. A total of eight putative potato TPS genes (StTPSs) were identified by searching the latest potato genome sequence. The amino acid identity among eight StTPSs varied from 59.91 to 89.54%. Analysis of d N /d S ratios suggested that regions in the TPP (trehalose-6-phosphate phosphatase) domains evolved faster than the TPS domains. Although the sequence of the eight StTPSs showed high similarity (2571-2796 bp), their gene length is highly differentiated (3189-8406 bp). Many of the regulatory elements possibly related to phytohormones, abiotic stress and development were identified in different TPS genes. Based on the phylogenetic tree constructed using TPS genes of potato, and four other Solanaceae plants, TPS genes could be categorized into 6 distinct groups. Analysis revealed that purifying selection most likely played a major role during the evolution of this family. Amino acid changes detected in specific branches of the phylogenetic tree suggests relaxed constraints might have contributed to functional divergence among groups. Moreover, StTPSs were found to exhibit tissue and treatment specific expression patterns upon analysis of transcriptome data, and performing qRT-PCR., Conclusions: This study provides a reference for genome-wide identification of the potato TPS gene family and sets a framework for further functional studies of this important gene family in development and stress response.

Background: The objective of this study was to investigate the distribution and susceptibility of aerobic and facultative Gram-negative bacilli isolated from Chinese patients with UTIs collected within 48 h (community acquired, CA) or after 48 h (hospital acquired, HA) of hospital admission., Methods: From 2010 to 2014, the minimum inhibitory concentrations (MICs) of 12 antibiotics for 4,332 aerobic and facultative Gram-negative bacilli, sampled in 21 hospitals in 16 cities, were determined by the broth microdilution method., Results: Enterobacteriaceae composed 88.5% of the total isolates, with Escherichia coli (E. coli) (63.2%) the most commonly isolated species, followed by Klebsiella pneumoniae (K. pneumoniae) (12.2%). Non-Enterobacteriaceae accounted for only 11.5% of all isolates and included mainly Pseudomonas aeruginosa (P. aeruginosa) (6.9%) and Acinetobacter baumannii (A. baumannii) (3.3%). Among the antimicrobial agents tested, the susceptibility rates of E.coli to the two carbapenems, ertapenem and imipenem as well as amikacin and piperacillin-tazobactam ranged from 92.5 to 98.7%. Against K. pneumonia, the most potent antibiotics were imipenem (92.6% susceptibility), amikacin (89.2% susceptibility) and ertapenem (87.9% susceptibility). Although non-Enterobacteriaceae did not show high susceptibilities to the 12 common antibiotics, amikacin exhibited the highest in vitro activity against P. aeruginosa over the 5-year study period, followed by piperacillin-tazobactam, imipenem, ceftazidime, cefepime, ciprofloxacin, and levofloxacin. The Extended Spectrum Beta-Lactamase (ESBL) rates decreased slowly during the 5 years in E. coli from 68.6% in 2010 to 59.1% in 2014, in K. pneumoniae from 59.7 to 49.2%, and in Proteus mirabilis (P. mirabilis) from 40.0 to 26.1%. However, the ESBL rates were different in 5 regions of China (Northeast, North, East, South and Middle-China)., Conclusion: E. coli and K. pneumonia were the major pathogens causing UTIs and carbapenems and amikacin retained the highest susceptibility rates over the 5-year study period, indicating that they are good drug choices for empirical therapies, particularly of CA UTIs in China.

Background: Published information regarding the clinical characteristics, laboratory findings, and outcomes of patients with Mycobacterium tuberculosis (MTB) blood stream infection (BSI) is limited. We aimed in this study to evaluate the clinical characteristics, laboratory evaluation, and outcomes of patients with MTB BSI., Methods: All patients diagnosed with MTB BSI at Peking Union Medical College Hospital between January 2008 and May 2014 were identified by examining the electronic database listing results of all blood cultures. Data on demographics, clinical characteristics, laboratory manifestations, management, and outcomes were abstracted from medical records., Results: Six thousand nine hundred seventy-four patients had mycobacterial blood cultures during the study period. Of 48 patients (0.7%) with MTB BSI, 26 patients (54%) were considered to be immunocompromised (refers to a person who has a significantly impaired immune system). This was due to human immunodeficiency virus (HIV) infection (n = 2 of 48 tested), receiving steroids (n = 17, including 16 with rheumatic diseases and one with myasthenia gravis), malignancy (n = 3), diabetes mellitus (n = 3), and renal transplantation (n = 1). The main clinical manifestations were fever (100%, with a median of 40 °C), weight loss (48%) and cough with sputum production (46%). Most patients had one or more organs involved (81%). The median time from onset of fever to diagnosis was 8 weeks (IQR 5 ~ 14). Six patients died within 1 week after diagnosis. Of the 17 patients completing treatment, 14 patients (82%) recovered without major complications and they had a shorter time interval between onsets of symptoms to treatment compared to those died of TB., Conclusions: In this group of patients with MTB BSI, fever and multiple organs involvement were common, the outcome was poor and timely diagnosis and treatment might favor outcome.

Background: Mycoplasma hominis, a well known cause of neonatal infection, has been reported as a pathogen in urogenital infections in adults; however, central nervous system (CNS) infections are rare. We report here the first case of M. hominis meningitis in China, post neurosurgical treatment for an intracerebral haemorrhage in a 71-year-old male., Case Presentation: We describe a 71-year-old man who developed M. hominis meningitis after neurosurgical treatment and was successfully treated with combined azithromycin and minocycline therapy of 2 weeks duration, despite delayed treatment because the Gram stain of cerebrospinal fluid (CSF) yielded no visible organisms. The diagnosis required 16S rDNA sequencing analysis of the cultured isolate from CSF. Literature review of M. hominis CNS infections yielded 19 cases (13 instances of brain abscess, 3 of meningitis, 1 spinal cord abscess and 1 subdural empyema each). Delay in diagnosis and initial treatment failure was evident in all cases. With appropriate microbiological testing, antibiotic therapy (ranging from 5 days to 12 weeks) and often, multiple surgical interventions, almost all the patients improved immediately., Conclusions: Both our patient findings and the literature review, highlighted the pathogenic potential of M. hominis together with the challenges prompted by rare infectious diseases in particular for developing countries laboratories with limited diagnostic resources.

Background: Cigarette smoking is the most established risk factor, and genetic variants and/or gene promoter methylations are also considered to play an essential role in development of lung cancer, but the pathogenesis of lung cancer is still unclear., Methods: We collected the data of 150 cases and 150 age-matched and sex-matched controls on a Hospital-Based Case-Control Study in China. Face to face interviews were conducted using a standardized questionnaire. Gene polymorphism and methylation status were measured by RFLP-PCR and MSP, respectively. Logistic regressive model was used to estimate the odds ratios (OR) for different levels of exposure., Results: After adjusted age and other potential confounding factors, smoking was still main risk factor and significantly increased 3.70-fold greater risk of NSCLC as compared with nonsmokers, and the ORs across increasing levels of pack years were 1, 3.54, 3.65 and 7.76, which the general dose-response trend was confirmed. Our striking findings were that the risk increased 5.16, 8.28 and 4.10-fold, respectively, for NSCLC with promoter hypermethylation of the p16, DAPK or RAR beta gene in smokers with CYP1A1 variants, and the higher risk significantly increased in smokers with null GSTM1 and the OR was 17.84 for NSCLC with p16 promoter hypermethylation, 17.41 for DAPK, and 8.18 for RAR beta in smokers with null GSTM1 compared with controls (all p < 0.01)., Conclusion: Our study suggests the strong combined effects of cigarette smoke, CYP1A1 and GSTM1 Polymorphisms, hypermethylations of p16, DAPK and RAR beta promoters in NSCLC, implying complex pathogenesis of NSCLC should be given top priority in future research.

Background: Typhoid and paratyphoid fever are endemic in China. The objective of this investigation was to determine the molecular features of nalidixic acid-resistant Salmonella enteric serovar Typhi (S. typhi) and Paratyphi (S. paratyphi) from blood isolates in Shenzhen, China., Results: Twenty-five S. typhi and 66 S. paratyphi were isolated from 91 bacteremic patients between 2002 and 2007 at a hospital in Shenzhen, Southern China. Fifty-two percent (13/25) of S. typhi and 95.3% (61/64) of S. paratyphi A were resistant to nalidixic acid. Sixty-seven isolates of nalidixic acid-resistant Salmonella (NARS) showed decreased susceptibility to ciprofloxacin (MICs of 0.125-1 microg/mL). All 75 NARS isolates had a single substitution in the quinolone resistance-determining region (QRDR) of GyrA (Ser83-->Phe/Pro/Tyr, or Asp87-->Gly/Asn), and 90.7% of these isolates carried the substitution Ser83Phe in GyrA. No mutation was found in the QRDR of gyrB, parC, or parE. Plasmid mediated quinolone resistance genes including qnr and aac(6')-Ib-cr were not detected in any isolate. Twenty-two distinct pulsed field gel electrophoresis (PFGE) patterns were observed among S. typhi. Sixty-four isolates of S. paratyphi A belonged to one clone. Eighty-seven investigated inpatients were infected in the community. Six patients infected by S. paratyphi A had a travel history before infection., Conclusions: Nalidixic acid-resistant S. typhi and S. paratyphi A blood isolates were highly prevalent in Shenzhen, China. PFGE showed the variable genetic diversity of nalidixic acid-resistant S. typhi and limited genetic diversity of nalidixic acid -resistant S. paratyphi A.

Background: Genetic factors were considered as one of the risk factors for lung cancer or other cancers. The aim of this work was to determine whether a genetic predisposition accounts for such familial aggregation of cancer among relatives of lung cancer probands., Methods: A case-control study was conducted in 800 case families identified by lung cancer patients (probands), and in 800 control families identified by the probands'spouses. The data were analysed with logistic regression analysis model., Results: The data revealed a significantly greater overall risk of cancer (OR = 1.82, P < 0.01) in the proband group. The relatives of lung cancer probands maintained an increased risk of non-lung cancer (P < 0.05) after adjusting for confounder factors. The crude odds ratio of a proband family having one family member with cancer was 1.67 compared with control families. Proband families were 2.56 times more likely to have two other family members with cancer. For three cancers and four or more cancers, the risk increased to 3.50 and 5.91, respectively. The most striking differences in cancer prevalence between proband and control families were noted for cancer risk among female relatives. The strongest effects were for not only lung cancer in any female relatives (OR 2.17, 95%CI 1.60-3.64) and mothers (OR 2.78, 95%CI 1.23-5.12) and sisters (OR 2.03, 95%CI 1.26-3.97), but also non-lung cancer in females and mothers (OR 2.00, 95%CI 1.26-3.01, and OR 2.34, 95%CI 1.28-4.40, respectively)., Conclusion: These data support the hypothesis of a genetic susceptibility to cancer in families with lung cancer, and the female genetic susceptibility to cancer might be greater than male.