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ObjectiveThis study used whole-genome sequencing (WGS) to explore the genetic diversity, virulence factors, and antimicrobial resistance determinants of string test-positive Klebsiella pneumoniae (KP) over a 4-year surveillance period in Huzhou, China.MethodsIn total, 632 clinical isolates were collected via hospital surveillance from 2020 to 2023; 100 were positive in the string test and these 100 strains were subjected to antimicrobial susceptibility testing using an agar dilution method followed by WGS.ResultsThe resistance rates to cefotaxime (77.0%), trimethoprim-sulfamethoxazole (67.0%), and nalidixic acid (64.0%) were high. Multilocus sequence typing revealed high genetic diversity; there were 33 sequence types (STs) and 15 capsular serotypes. The most common ST was ST23 (16.0%) and the most common capsular serotype was K1 (22.5%). Virulome analysis revealed among-strain differences in virulence factors that affected bacterial adherence, efflux pump action, iron uptake, nutritional factors, metabolic regulation, the secretion system, and toxin production. The Kleborate strain-specific virulence scores of all 100 string test-positive KPs were derived: 28 strains scored 5, 28 scored 4, 21 scored 3, 12 scored 1, and 11 scored 0. All 77 strains with scores of 3 to 5 contained the iucA gene. The phylogeny based on whole-genome single nucleotide polymorphisms (wgSNPs) indicated high clonality; the string test-positive KP strains were grouped into six clades. Closely related isolates in each genetic cluster usually shared STs.ConclusionThe present study highlights the significance of the KP iucA gene in terms of hypervirulence and the diverse genotypes of string test-positive KP strains isolated in Huzhou hospitals.

Diarrheagenic Escherichia coli (DEC) is a common pathogen around the world that can cause disease with symptoms of diarrhoea. We collected all clinical DEC isolates from diarrhoea samples in three sentinel hospitals for active surveillance of foodborne diseases in Huzhou, China, between 2020 and 2022. The isolates were characterised according to demographic characteristics, time distribution, distribution of suspected culprit foods, antimicrobial results of susceptibility testing, analysis of virulence genes, and pulsed-field gel electrophoresis (PFGE) typing. The positive detection rate was 7.28%, the highest for enteroaggregative E. coli (EAEC) strains, followed by enterotoxic E. coli (ETEC) strains. The predominant virulence genes were astA/pic in EAEC (57.25%) and estIa/estIb in ETEC (17.94%) strains. The proportion of cases was relatively high in children aged 6 years old (15.27%), and the peak of incidence was between June and September. The rates of drug resistance in DEC were high in Huzhou, and the spectrum of drug resistance was wide. The highest rate of drug resistance was for AMP (63.51%), and multiple drug resistance was common. The household was the leading site of DEC infection, and meat and meat products were the main suspected culprit foods (18.15%). EAEC strains showed 52.4-100.00% sequence identity, and ETEC strains showed 52.2-100.00% sequence identity. All cases of DEC infection in Huzhou were sporadic between 2020 and 2022. Strengthening continuous surveillance will be useful in the risk assessment of foodborne diseases caused by DEC.

【Objective】The purpose of this study was to explore the prevalence and genetic variation of canine parvovirus (CPV) in Xinxiang City, Henan Province, and provide reference for effective prevention and control of regional CPV epidemics.【Method】In this study, 23 stool samples and eye, nose, mouth and anus swabs of dogs suspected of CPV disease collected from several pet hospitals in Xinxiang were first pretreated and then PCR detected. The corresponding samples with positive PCR detection results were soaked, filtered and sterilized, and then inoculated into feline kidney cell (CRFK) for virus proliferation and culture. The isolated virus was observed under a transmission electron microscopy. Referring to the sequences of different subtypes of CPV both domestically and internationally included in GenBank, PCR was used for segmented amplification, followed by sequencing and splicing to obtain the full length genes of the virus. Molecular biology software was used for sequence analysis and amino acid homology analysis of the virus genes.【Result】One CPV was successfully isolated from the sample sent for examination and designated strain XX-2022. The virus strain was able to produce significant cytopathic changes in the CRFK cells, resulting in cell rounding, pulling and falling off. Transmission electron microscopy can observe typical canine parvovirions in a circular or hexagonal shape with a diameter of approximately 25 nm and no capsule. The full genome sequence of this virus, 4 588 bp in length, was obtained by PCR segmental amplification. Phylogenetic analysis results showed that the XX-2022 strain CPV had a close relationship with the Canine/SH/1/2019 (MN840830.1) strain CPV. The amino acid sequence of the VP2 gene of XX-2022 strain, which shares 99.7% amino acid identity with the VP2 amino acid sequence of YANJI-5 (MW715601), was analyzed using megalign software. Based on the genotyping principles of CPV, it was finally determined that the XX-2022 strain CPV belonged to CPV-2a type.【Conclusion】In this study, a CPV strain was successfully isolated from clinical material, determined as CPV-2a type, which provide a basis for the study of the epidemiology, pathogenicity, and biological characteristics of CPV in Xinxiang, as well as a reference for the regional prevalence and effective prevention and control of CPV, and to provide an endemic virus for the development of new vaccines.

Objective To investigate the serotypes, virulence genes, antimicrobial resistance and molecular characteristics of Vibrio parahaemolyticus in Huzhou of Zhejiang Province. Methods Isolates of 92 V. parahaemolyticus in Huzhou were analyzed by serological typing, virulence gene detection, antibiotic resistance testing, and pulsed-field gel electrophoresis(PFGE) for molecular typing. Results O3 ∶ K6 was the main serotype and tlh+tdh+trh- was the most frequently detected virulence genotype in clinical strains. O2 ∶ Kut was the main serotype and tlh+tdh-trh- was the most frequently detected virulence genotype in environmental strains. Antibiotic resistance testing indicated that the isolates were highly resistant to ampicillin(90. 22%, 83/92), followed by gentamicin and tetracycline. Following the restriction enzyme Not I digestion, the 91 strains yielded 81 PFGE patterns, and 16 clones had similarity values of >85.00%. Conclusion The etiologic characteristics of V. parahaemolyticus varied, which might be one of the reasons for high incidence of foodborne disease in Huzhou. There may be cross-contamination between freshwater and seawater products, so it is necessary to strengthen supervision of food processing.

Infection caused by noroviruses (NoVs) is one of the most important causes of acute gastroenteritis in humans worldwide. To gain insight into the epidemiology of and genetic variation in NoV strains, stool samples collected from 18 outbreaks of acute gastroenteritis in Huzhou, China, between January 2008 and December 2012 were analyzed. Samples were tested for NoVs by real-time RT-PCR. Partial sequences of the RNA- dependent RNA polymerase (RdRp) and capsid gene of the positive samples were amplified by RT-PCR, and the PCR products were sequenced and used for phylogenetic analysis. NoVs were found to be responsible of 88.8% of all nonbacterial acute gastroenteritis outbreaks in Huzhou over the last 5 years. Genogroup II outbreaks largely predominated and represented 93% of all outbreaks. A variety of genotypes were found among genogroups I and II, including GI.4, GI.8, GII.4, and GII.b. Moreover, phylogenetic analyses identified two recombinant genotypes (polymerase/capsid): GI.2/GI.6 and GII.e/GII.4 2012 Sydney. GII.4 was predominant and involved in 8/10 typed outbreaks. During the study period, GII.4 NoV variants 2006b, New Orleans 2009, and Sydney 2012 were identified. This is the first report of the detection of GII.4 New Orleans 2009 variant, GII.e/GII.4 Sydney 2012 recombinant in outbreaks of acute gastroenteritis in China.

Abstract Placental hypoxia is hazardous to maternal health as well as fetal growth and development. Preeclampsia and intrauterine growth restriction are common pregnancy problems, and one of the causes is placental hypoxia. Placental hypoxia is linked to a number of pregnancy illnessesv. To investigate their potential function in anoxic circumstances, we mimicked the anoxic environment of HTR-8/Svneo cells and performed lncRNA and circRNA studies on anoxic HTR-8/Svneo cells using high-throughput RNA sequencing. The miRNA target genes were predicted by integrating the aberrant expression of miRNAs in the placenta of preeclampsia and intrauterine growth restriction, and a ceRNA network map was developed to conduct a complete transcriptomic and bioinformatics investigation of circRNAs and lncRNAs. The signaling pathways in which the genes were primarily engaged were predicted using GO and KEGG analyses. To propose a novel explanation for trophoblastic organism failure caused by lncRNAs and circRNAs in an anoxic environment.

Background: Norovirus (NoV) has been recognized as the leading cause of both outbreaks and sporadic cases of acute gastroenteritis in children and adults worldwide. Stool samples collected from outpatients with clinical symptoms of acute gastroenteritis in all age groups at the First People's Hospital in Huzhou, Huzhou, China between March 2014 and February 2015 were analyzed to gain insight into the epidemiology and genetic variation in NoV strains circulating in China. Method: Real-time RT-PCR (qPCR) was performed for Norovirus detection. RT-PCR were used for genomic amplification and sequencing. Genogroup and genotype were assigned using the NoV Noronet typing tool and the strains were named according to the time of isolation. The phylogenetic analysis was conducted using MEGA 5. Results: Of the 809 specimens, 193 (23.9 %) were positive for NoV, with GII.4 and GII.17 the most commonly identified strains. Phylogenetic analysis confirmed the presence of five recombinant strains in Huzhou. Recombinants GII.P13/GII.17 and GII.P12/GII.4 were newly detected in China. The GII.P13/GII.17 recombinant was first identified in October 2014 and steadily replaced GII.Pe/GII.4 (GII.4 Sydney 2012) as the predominant circulating NoV genotype. Conclusion: This is the first report of the detection of GII.17 in the Huzhou area and of a NoV genotype being detected in greater numbers than GII.4. Furthermore, our results indicated that following the emergence of GII.17 in October 2014, it steadily replaced the previous circulating GII.4 Sydney2012 strain, which was the dominant circulating genotype for the past 2 years. As norovirus are the important cause of nonbacterial gastroenteritis, continuous and comprehensive study of the norovirus strains involved in large and cost-effective acute gastroenteritis would help understanding the molecular epidemiology of norovirus infections and development of improved prevention and control measures. [ABSTRACT FROM AUTHOR]