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ObjectiveTo provide scientific basis for the prevention and control of foodborne diseases and clinical treatment， the serological， drug resistance and molecular typing characteristics of Salmonella isolated from patients with foodborne diarrhea in Wenzhou City was investigated.MethodsA total of 567 Salmonella strains isolated from foodborne diarrhea cases in Wenzhou City from 2017 to 2021 were sorted out and serotyped. The susceptibility tests to 15 antimicrobial agents were performed using the broth microdilution method. Pulsed field gel electrophoresis （PFGE） was used for molecular typing.ResultsAmong the 567 patients of Salmonella， 326 were male and 241 were female， accounting for 57.5% and 42.5%， respectively. Most of them were children under 6 years old， and 119 strains were isolated， accounting for 21.0%. Next was the elderly over 60 years old， 111 strains of Salmonella were isolated， accounting for 19.6%. The 567 isolates of Salmonella were divided into 50 serotypes， among which the top two serotypes were Salmonella typhimurium （33.5%， 190/567） and Salmonella enteritidis （23.6%， 134/567）. The results showed that the resistance rate to ampicillin was the highest （73.5%， 417/567）. It was followed by tetracycline （63.3%， 359/567）. Salmonella typhimurium had the highest resistance to tetracycline （84.2%， 160/190）， and Salmonella enteritidis had the highest resistance to nalidixic acid （95.5%， 128/134） among 15 antibiotics. Among 567 strains of Salmonella， 178 kinds of drug resistance spectrum were found， the rate of multiple drug resistance was 62.6%and the highest proportion was AMP-AMS-CFZ-CT-NAL. The 201 strains of Salmonella typhimurium and the monophasic varieties of Salmonella typhimurium produced 70 band types. The band types varied greatly and the similarity was between 1.5% and 100%. One hundred and twenty-seven strains of Salmonella enteritidis obtained a total of 32 band types with the similarity between 35.8% and 100%. Fifty strains of Salmonella london obtained a total of 24 band types by PFGE， and the similarity was between 40.0% and 100%.ConclusionFoodborne Salmonella strains isolated in Wenzhou displayed diverse serotypes， varying degrees of drug resistance， and multi-drug resistance. To effectively prevent and control foodborne diseases caused by Salmonella， enhancing monitoring of Salmonella among foodborne diarrhea patients was essential. Timely understanding of Salmonella serotype distribution trends and drug resistance patterns in the region， followed by appropriate measures， was imperative.

ObjectiveTo investigate the distribution and molecular typing characters of Yersinia enterocolitica in food in Wenzhou.MethodsAfter pre-enrichment of samples at 4 ℃， the selective media was used for the isolation and identification of Yersinia enterocolitica from food. The biotype， serotype， virulence genotype， drug resistance and pulsed field gel electrophoresis， （PFGE） molecular typing of the isolated strains were analyzed.ResultsAmong 676 samples in 6 categories， 69 Yersinia enterocolitica strains were isolated from 68 samples， with a positive rate of 10.1% （68/676）. The detection rate of prepared meat products was the highest （20.5%， 9/44）， followed by quick-frozen food （17.2%， 11/64）. Biotype 1A accounted for 95.7% （66/69） of the isolates， and the predominant bioserotype was 1A/O∶5 （29.0%）， followed by 1A/O∶8（14.5%）. 88.4% （61/69） of the strains only harbored ystB gene. Particularly， there was a bioserotype 4/O∶3 strain carried the virulence gene of ail， ystA， yadA and virF. The sensitivity rates of the isolates to 14 kinds of antibiotics were over 94%. Thirty two serotyped strains were divided into 29 PFGE patterns.ConclusionFood was contaminated by Yersinia enterocolitica to some degree in Wenzhou， and the pathogenic strain was detected. The antibiotic resistance rate of Yersinia enterocolitica was at a low level， and PFGE suggested highly genetic polymorphism.

Abstract Background Rainbow trout (Oncorhynchus mykiss) are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL) have been identified for production and life-history traits in rainbow trout. An integrated physical and genetic map is needed to facilitate fine mapping of QTL and the selection of positional candidate genes for incorporation in marker-assisted selection (MAS) programs for improving rainbow trout aquaculture production. Results The first generation integrated map of the rainbow trout genome is composed of 238 BAC contigs anchored to chromosomes of the genetic map. It covers more than 10% of the genome across segments from all 29 chromosomes. Anchoring of 203 contigs to chromosomes of the National Center for Cool and Cold Water Aquaculture (NCCCWA) genetic map was achieved through mapping of 288 genetic markers derived from BAC end sequences (BES), screening of the BAC library with previously mapped markers and matching of SNPs with BES reads. In addition, 35 contigs were anchored to linkage groups of the INRA (French National Institute of Agricultural Research) genetic map through markers that were not informative for linkage analysis in the NCCCWA mapping panel. The ratio of physical to genetic linkage distances varied substantially among chromosomes and BAC contigs with an average of 3,033 Kb/cM. Conclusions The integrated map described here provides a framework for a robust composite genome map for rainbow trout. This resource is needed for genomic analyses in this research model and economically important species and will facilitate comparative genome mapping with other salmonids and with model fish species. This resource will also facilitate efforts to assemble a whole-genome reference sequence for rainbow trout.

Abstract Background Rainbow trout (Oncorhynchus mykiss) are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL) have been identified for production and life-history traits in rainbow trout. A bacterial artificial chromosome (BAC) physical map is needed to facilitate fine mapping of QTL and the selection of positional candidate genes for incorporation in marker-assisted selection (MAS) for improving rainbow trout aquaculture production. This resource will also facilitate efforts to obtain and assemble a whole-genome reference sequence for this species. Results The physical map was constructed from DNA fingerprinting of 192,096 BAC clones using the 4-color high-information content fingerprinting (HICF) method. The clones were assembled into physical map contigs using the finger-printing contig (FPC) program. The map is composed of 4,173 contigs and 9,379 singletons. The total number of unique fingerprinting fragments (consensus bands) in contigs is 1,185,157, which corresponds to an estimated physical length of 2.0 Gb. The map assembly was validated by 1) comparison with probe hybridization results and agarose gel fingerprinting contigs; and 2) anchoring large contigs to the microsatellite-based genetic linkage map. Conclusion The production and validation of the first BAC physical map of the rainbow trout genome is described in this paper. We are currently integrating this map with the NCCCWA genetic map using more than 200 microsatellites isolated from BAC end sequences and by identifying BACs that harbor more than 300 previously mapped markers. The availability of an integrated physical and genetic map will enable detailed comparative genome analyses, fine mapping of QTL, positional cloning, selection of positional candidate genes for economically important traits and the incorporation of MAS into rainbow trout breeding programs.

Aims Cronobacter spp. are emerging food-borne pathogens capable of causing life-threatening illness via several distinct routes. Although endeavors to reduce the incidence of Cronobacter infections are implemented, potential risk of these microorganisms on food safety remains poorly understood. Here, we evaluated the genomic features of clinical Cronobacter and the possible food reservoirs of these infections. Methods and results Whole-genome sequencing (WGS) data of all human clinical cases (n  = 15) during 2008–2021 in Zhejiang were used and compared to sequenced Cronobacter genomes (n  = 76) representing various food products. Cronobacter strains exhibited a high degree of genetic diversity by WGS-based subtyping. A variety of serotypes (n  = 12) and sequence types (n  = 36) were identified, including six novel STs (ST762-ST765, ST798, and ST803) first-time described in this study. Nine clinical clusters representing 12/15 (80%) patients match a potential food source. Genomic insights into virulence genes revealed species/hosts specificity signatures associated with autochthonous populations. Resistance to streptomycin, azithromycin, sulfanilamide isoxazole, cefoxitin, amoxicillin, ampicillin, and chloramphenicol, as well as multidrug resistance, was noted. WGS data can be used to predict resistance phenotypes in amoxicillin, ampicillin, and chloramphenicol, which were extensively used in clinical treatment. Conclusions The wide dissemination of pathogenic potential and antibiotic-resistant strains in multiple food sources emphasized the importance of rigorous food safety policies to reduce Cronobacter contamination in China. [ABSTRACT FROM AUTHOR]

In order to develop high power lithium ion batteries (LIBs), urgent requirements including adequate safety, higher current density and superior cyclic stability are proposed for separator. Tissue paper, composed of packed cellulose fibers, possesses lower production cost, easier accessibility, superior wettability together with outstanding thermostability, and is thus a candidate to be the substrate for high performance separator. To address the issue of structural failure usually encountered by single polymer as binder during long term cycling, crosslinked binder was constructed on tissue paper to adhere nano-SiO2 through chemical reactions between poly (vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) and hyperbranched polyethyleneimine (PEI) in this work. The effects of crosslinking degree on physical properties and electrochemical performance were studied thoroughly. When the feed ratio of PVDF-HFP and PEI is fixed at 10:1, the crosslinked composite separator displays excellent electrolyte uptake and wettability, superior ionic conductivity, better interfacial compatibility as well as higher Li+ transference number (0.56), thus offering battery with prominent rate capabilities. Besides, this crosslinked composite separator exhibits satisfying dimensional stability even treated at 250 °C, better flame retardancy, enhanced mechanical behavior, wider electrochemical window and outstanding cycle stability. Accordingly, tissue paper-based crosslinked composite separators can meet higher requirements put forward by high power LIBs. [ABSTRACT FROM AUTHOR]

Abstract Background Barrett's esophagus (BE) is caused by gastroesophageal reflux with consecutive mucosal inflammation, predisposing patients to the development of esophageal adenocarcinoma (EAC). We investigated changes in T cell-related mucosal combinatorial molecular protein patterns in both diseases using the novel Multi-Epitope-Ligand-Cartography, a unique robotic whole-cell imaging technology that simultaneously visualizes dozens of proteins in structurally intact tissues and correlates cellular localization of proteins with function. Results Biopsies were taken during endoscopy from BE, EAC, and normal control tissue, and proteomic microscopy was performed on 32 different epitopes. When the significance level was set to p < 0.0005 and the search depth to five antibody combinations, controls and BE can be differentiated by 63, controls and EAC by 3222, and BE from EAC by 1521 distinct protein combinations. For example, the number of activated apoptotic naïve and memory T cells was significantly increased only in BE, whereas the number of activated apoptotic helper and regulatory T cells was significantly elevated in BE and EAC. In contrast, the number of activated apoptotic cytotoxic T cells was significantly elevated only in EAC. Confirming different pathways in BE and EAC, the number of T lymphocytes with p53 expression and downregulation of bcl2 expression (CD3+p53+Bcl2-NfkB-) was significantly increased in EAC compared to BE and controls. Interestingly, the number of precursor T cells (CD7+) was significantly elevated only in EAC. These cells lack Bax and caspase-8, suggesting impaired apoptosis in the early stages of T cell differentiation. Conclusion Proteomic analysis showed for the first time that proteins, which are critically involved in the mucosal immune system of the esophagus, are distinctly expressed in BE and EAC, whereas others are comparably altered in both diseases, suggesting that many pathogenic events might be shared by both diseases. Topological proteomic analysis, therefore, helps us to understand the different pathogenic events in the underlying disease pathways.

Abstract Background Rainbow trout (Oncorhynchus mykiss) are the most-widely cultivated cold freshwater fish in the world and an important model species for many research areas. Coupling great interest in this species as a research model with the need for genetic improvement of aquaculture production efficiency traits justifies the continued development of genomics research resources. Many quantitative trait loci (QTL) have been identified for production and life-history traits in rainbow trout. A bacterial artificial chromosome (BAC) physical map is needed to facilitate fine mapping of QTL and the selection of positional candidate genes for incorporation in marker-assisted selection (MAS) for improving rainbow trout aquaculture production. This resource will also facilitate efforts to obtain and assemble a whole-genome reference sequence for this species. Results The physical map was constructed from DNA fingerprinting of 192,096 BAC clones using the 4-color high-information content fingerprinting (HICF) method. The clones were assembled into physical map contigs using the finger-printing contig (FPC) program. The map is composed of 4,173 contigs and 9,379 singletons. The total number of unique fingerprinting fragments (consensus bands) in contigs is 1,185,157, which corresponds to an estimated physical length of 2.0 Gb. The map assembly was validated by 1) comparison with probe hybridization results and agarose gel fingerprinting contigs; and 2) anchoring large contigs to the microsatellite-based genetic linkage map. Conclusion The production and validation of the first BAC physical map of the rainbow trout genome is described in this paper. We are currently integrating this map with the NCCCWA genetic map using more than 200 microsatellites isolated from BAC end sequences and by identifying BACs that harbor more than 300 previously mapped markers. The availability of an integrated physical and genetic map will enable detailed comparative genome analyses, fine mapping of QTL, positional cloning, selection of positional candidate genes for economically important traits and the incorporation of MAS into rainbow trout breeding programs.