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ObjectiveTo investigate the serotype distribution and antimicrobial resistance characteristics of Salmonella isolated from retail chicken in Beijing City.MethodsA total of 135 Salmonella strains were isolated from retail chicken meat collected from three large wholesale markets in Fengtai District in Beijing City from 2014 to 2015. The serotype of these Salmonella strains was identified using both a Luminex serotyping kit and a traditional serum agglutination method. Multilocus sequence typing was performed according to the recommended conditions of the Enterobase database. Antimicrobial susceptibility testing plates were used to determine the susceptibility of the isolates against 12 classes of drugs representing 25 antimicrobial agents. PCR was used to detect the prevalence of the 10 mobile colistin resistance genes （mcr） and three NDM-type carbapenemases genes （blaNDM）.ResultsAmong the 135 Salmonella strains， 6 serogroups were detected， with D1 and B being the main serogroups； 20 serotypes were detected， in which Enteritidis， Indiana， and Thompson were the dominant ones with percentages of 50.4%， 15.6%， and 8.1%， respectively； 21 ST types were obtained， and a good correspondence was observed between serotypes and ST types. 91.9% of all tested isolates showed resistance to the tested drugs and showed the highest resistance to nalidixic acid， ampicillin， ampicillin-sulbactam， tetracycline. Multi-drug resistant strains accounted for 71.1% of all strains and were resistant to as many as 18 kinds of antimicrobial compounds belonging to 10 categories. Among the 17 strains co-resistant to 8 or more classes of drugs， 16 were of the Indiana serotype. The proportion of strains with high multi-drug resistance was different in different packaging methods， different seasons， and different wholesale markets. All strains were negative for the mcr and blaNDM genes.ConclusionThe serotypes of Salmonella isolates from chicken meat in wholesale markets in Beijing City from 2014 to 2015 were complex， with the dominant serotype of Salmonella Enterititis， and the overall antimicrobial resistance level of all isolates was high. To assess the possible food safety risks， continuous monitoring for Salmonella Indiana with high levels of antimicrobial resistance must be carried out and their drug resistance and transmission mechanisms must be studied to help develop first-line and ultimate drugs for clinical treatment of Salmonella diseases.

The microbial control in broiler chicken slaughtering and processing is essential in ensuring food safety and human health. Scalding， washing， and cooling are crucial stages for controlling microbial contamination during broiler chicken processing， and a combined use of multiple measures can effectively reduce microbial load on broiler chicken carcasses. Among these antimicrobial agents， sodium hypochlorite， cetylpyridinium chloride， and acidified sodium chlorite are effective in reducing contamination by pathogens such as Salmonella， Escherichia coli， and Campylobacter on broiler chicken carcasses. However， the effectiveness of reducing microbes depends on the stages of microbial control and the amount and duration of antimicrobial agent application. This article provides an overview of the control measures for microbial contamination at various stages of broiler chicken slaughtering and processing. Additionally， this study systematically elucidates the microbial reduction effects of various antimicrobial agents in these process stages. This review aims to provide data references for preventing and controlling microbial contamination during broiler chicken slaughtering and processing in domestic industries， thereby promoting the healthy development of the broiler production industry and safeguarding consumer health.

The lithology and hardness of the coal seam roof are directly related to the stability and water permeability of the roadway and the safe production of the coal mine. It has become a common method to predict gas content based on AVO inversion, but the conventional AVO inversion formula is a simplified approximation of Zoeppritz equation in different degrees under certain conditions, which affects the inversion accuracy to some extent. On the basis of petrophysical analysis of the roof, the pre-stack inversion of quasi-linear Zoeppritz equation with the smallest overall angle error was employed to lithology and hardness prediction of coal seam roof in Yangquan Mining Area, Shanxi Province. The results show that the expression of quasi-linear Zoeppritz equation is simple, and through the AVO characteristic analysis of different Zoeppritz approximate formulas, found that the precision of quasi-linear Zoeppritz equation is the highest, second only to that of accurate Zoeppritz equation. The analysis of rock mechanics characteristics shows that Young’s modulus multiplied by density is the most sensitive to hardness, and pseudo-gamma P-wave velocity can effectively reflect roof lithology. The lithology and hardness characterization parameters obtained from inversion are combined with the parameter well data and geological data to comprehensively evaluate the roof stability, provide geological evidence for roadway excavation and reduce the coal mine production risk.

ObjectiveA dual real-time polymerase chain reaction (PCR) method for simultaneous detection of two virulence genes tdh and trh of Vibrio parahaemolyticus was established, and the virulence genes carried by 2 771 strains of foodborne Vibrio parahaemolyticus in China were comprehensively detected.MethodsAccording to the tdh and trh virulence genes of Vibrio parahaemolyticus, PCR primers and fluorescent probes were designed respectively, the real-time PCR reaction system and reaction procedure were optimized, and a dual real-time PCR detection method which can detect the two virulence genes at the same time was established. The virulence genes carried by 2 771 strains of foodborne Vibrio parahaemolyticus isolated in 2015 and 2016 were detected by the established method, and compared with the result of PCR method to evaluate the sensitivity, accuracy and specificity of the method.ResultsThe established dual fluorescence PCR method could detect both tdh and trh virulence genes at the same time, and its sensitivity was 1.5×10-4 ng/μL. The accuracy and specificity were 100%. In 2015, the carrying rates of tdh and trh genes in foodborne Vibrio parahaemolyticus in China were 0.26% (3/1 137) and 1.67%(19/1 137) respectively, and were 0.24%(4/1 634) and 0.43%(7/1 634) in 2016 respectively.ConclusionIn this study, a dual real-time PCR method for simultaneous detection of tdh and trh virulence genes of Vibrio parahaemolyticus was established, which could quickly and accurately screen the virulence genes of Vibrio parahaemolyticus. The carrying rate of tdh and trh virulence genes of Vibrio parahaemolyticus isolated from food in China was low. The dual real-time PCR method can be applied to the study of the pathogenicity of Vibrio parahaemolyticus in food, and provide scientific data for the risk assessment of dietary exposure to Vibrio parahaemolyticus in China.

ObjectiveWhole genome sequencing and analysis was conducted on a Burkholderia gladiolus pv. cocovenenans strain, isolated from raw corn flour sample which caused family agglutinative bongkrekic acid poisoning. The genetic characteristics of its virulence and pathogenicity were analyzed as well.MethodsGenomic DNA was extracted from DBJ isolate, the whole genome sequencing was carried out. Bioinformatics method were used to mine and analyze the data obtained from sequencing.ResultsTwo independent chromosomes (G1 and G2) and one plasmid (P) were found in DBJ isolate. The lengths of the chromosomes and plasmid were about 4 Mb and 300 kb respectively. The GC content of the two chromosomes was both around 68.0%, and that of the plasmid was slightly lower at 63.0%. The bon gene cluster was found on chromosome G2. The phylogenetic analysis showed that DBJ isolate and UCD-UG_CHAPALOTE stain which was isolated from corn sample in Canada were in the same clade. Among 255 strains, 31 carrying bon gene cluster and they had obvious genetic evolutionary tendency.ConclusionThe bon gene cluster was located on the chromosome of Burkholderia gladiolus pv. cocovenenans DBJ, and it was the main pathogenic gene causing food poisoning in human.

Objective Campylobacter species are the main causes of foodborne illness worldwide, posing significant threats to public health. This study aimed to investigate the antibiotic resistance and genomic characterization of C. jejuni/C.coli from retail chickens in Beijing. Methods Antimicrobial susceptibility testing was conducted on 126 C. jejuni/C. coli isolated from retail chickens in Beijing, following CLSI protocols. Whole genomes of all isolates were sequenced using the Illumina platform. Results More C. coli (83.82%) showed multi-drug resistance than C. jejuni (8.62%). Genomic analysis demonstrated 42 sequence types (STs) and 12 clonal complexes (CCs), from which CC828 and CC52 were dominant. cdtA, cdtB and cdtC encoding cytotoxic protein were present spontaneously in most C. jejuni but not found in any C. coli isolates. The abundances of antibiotic resistance genes (ARGs) and virulence genes (VGs) in C. jejuni and C. coli were significantly different, with ARGs numbered in C. coli and VGs in C. jejuni. Conclusions High prevalence of multi-drug resistance C. coli and C. jejuni isolated from Beijing chickens were challenging clinical antibiotic usages in the treatment of Campylobacter infection. The surveillance of particular C. jejuni and C. coli STs correlated with higher resistance and virulence needs to be strengthened in the future. [ABSTRACT FROM AUTHOR]

Burkholderia gladioli pv. cocovenenans (B. cocovenenans) and its lethal toxin, bongkrekic acid (BA), have been causing frequent incidents of food poisoning in China, resulting in increased attention. The toxin is produced by B. cocovenenans under appropriate temperature and humidity, and mainly targets the inner mitochondrial membrane to cause toxic effects. At present, there are methods available for detecting BA, but the detoxification mechanism is not perfect. This review summarizes the naming process, biological characteristics, toxin production conditions, and sources of B. cocovenenans, as well as the physical and chemical properties, poisoning mechanism, clinical presentation, detection methods, and detoxification of BA. Additionally, the review provides recommendations for preventing bongkrekic acid poisoning. [ABSTRACT FROM AUTHOR]

Intestinal injuries caused by ionizing radiation (IR) are a major complication of radiotherapy. Ferrostatin-1 (Fer-1) exerts antioxidant and anti-inflammatory effects. We investigated the influence of Fer-1 on IR-induced intestinal damage and explored the possible mechanisms. IEC-6 cells were administrated with Fer-1 for 30 min and subsequently subjected to 9.0 Gy-irradiation. Flow cytometry, qPCR, and WB were used to detect changes. For in vivo experiments, Fer-1 was given intraperitoneally to mice at 1 h before and 24 h after 9.0 Gy total body irradiation (TBI) respectively. Three days after TBI, the small intestines were isolated for analysis. The diversity and composition of the gut microbiota were analyzed by 16S rRNA gene sequencing. In vitro, Fer-1 protected IEC-6 cells from IR injury by reducing the production of ROS and inhibiting both ferroptosis and apoptosis. In vivo, Fer-1 enhanced the survival rates of mice subjected to lethal doses of IR and restored intestinal structure and physiological function. Further investigation showed that Fer-1 protected IEC-6 cells and mice by inhibiting the p53-mediated apoptosis signaling pathway and restoring the gut-microbe balance. This study confirms that Fer-1 protects intestinal injuries through suppressing apoptosis and ferroptosis. [ABSTRACT FROM AUTHOR]

Objective: Non-typhoidal Salmonella (NTS) is a major cause of human salmonellosis globally. Food animals are major NTS reservoirs. An increase in antimicrobial resistance (AMR) in foodborne NTS has led to clinical treatment failures. Here, to examine the prevalence and perform characterization of foodborne NTS with AMR in China, we tested the antimicrobial susceptibility of 1,256 NTS isolates cultured from retail foods in 2020 in China. Methods: The antimicrobial susceptibility of 26 antimicrobial agents representing 12 classes was evaluated with the broth-microdilution method; the presence of ten mcr genes was screened with multi-PCR. The complete closed genomes of mcr-gene-carrying isolates were generated by hybrid assembly through whole genome sequencing on both the PacBio and Illumina platforms. Genomic features and genetic environments of the mcr-1 gene were analysed. Results: The overall drug resistance rate was 92.28%, and the multi-drug resistance (MDR) rate was 76.53%. A total of 341 AMR profiles were determined, and resistance was highest to nalidixic acid (63.38%). Among 887 NTS isolates with MDR, 232 showed co-resistance to cefotaxime and ciprofloxacin, and 25 were resistant to ten classes of antimicrobial agents. The resistance of NTS isolated from different regions varied. Isolates from raw chicken sources most frequently showed resistance. Four NTS carried the mcr-1 gene and represented four different serotypes. Four mcr-1 gene-bearing plasmids from the four Salmonella isolates were classified into two replicon types (IncI2 and IncHI2A). Two mcr-1 genes in IncI2 type plasmids were found to be located between a PAP2 family protein-encoding gene and a relaxaseencoding gene, whereas the other two mcr-1 gene structures in IncHI2A type plasmids showed variations in the presence of insertion sequences. Conclusion: Our data demonstrated severe AMR among foodborne NTS isolated from food in China, thus highlighting the importance of antimicrobial susceptibility surveillance to decrease the spread of AMR, particularly to critical drugs in human medicine. [ABSTRACT FROM AUTHOR]

Background: Gynecological diseases threaten women's health, and vaginal microecological testing is a common method for detecting gynecological diseases. Efficient and accurate microecological testing methods have always been the goal pursued by gynecologists.Objective: In order to automatically identify different types of microbial images in vaginal micromorphology detection, this paper proposes a vaginal microecological image recognition method based on Gabor texture analysis combined with long and short-term memory network (LSTM) model.Method: Firstly, we denoise the microecological morphological im-ages, which selects the area of interest and sets the label of the microorganism according to the doctors label. Secondly, texture analysis is carried out for the region of interest, which uses Gabor filters with 8 directions and 5 scales to filter the region of interest to extract the texture features on the image. Comparing the differences between different microbial image features, and screening suitable features to reduce the number of features. Then, we design an LSTM model to analyze the relationship of image features in different categories of microorganisms. Finally, we use the full connection layer and Softmax function to realize the automatic recognition of different microbial images.Results: The experimental results show that the image classification accuracy of 8 common microorganisms is 81.26%.Conclusion: Texture analysis combined with LSTM network strategy can identify different kinds of vaginal micro ecological images. Gabor-LSTM model has better classification effect on imbalanced data sets. [ABSTRACT FROM AUTHOR]

This study assesses changes of circulating leukocyte subpopulations and the expression of checkpoint receptors in T cells in patients undergoing radiochemotherapy. Fifty-seven patients with either esophageal cancer or cervical cancer who received radiochemotherapy were recruited into this study. Serial blood collection was carried out before and during treatments. Leukocyte subpopulations and the level of PD-1 and CTLA-4 in T cells were determined by flow cytometry. The plasma concentrations of 34 human cytokines, chemokines, and growth factors were quantified. Significant decreases of lymphocyte count and percentage of T cells and B cells were observed during radiochemotherapy. Percentages of PD-1hi and CTLA-4hi populations in T cells increased after treatments. Proportion of activated T cells showed no significant difference. No significant changes in the plasma concentrations of the 34 humoral mediators except mild decreases of six cytokines. Elevated expression of PD-1 and CTLA-4 in T cells in patients receiving radiochemotherapy, which suggests that exhaustion-like T-cell dysfunction develops during cancer cytotoxic treatments. [ABSTRACT FROM AUTHOR]

Ionizing radiation (IR)‐induced intestinal damage is the major and common injury of patients receiving radiotherapy. Urolithin A (UroA) is a metabolite of the intestinal flora of ellagitannin, a compound found in fruits and nuts such as pomegranates, strawberries and walnuts. UroA shows the immunomodulatory and anti‐inflammatory capacity in various metabolic diseases. To evaluate the radioprotective effects, UroA(0.4, 2 and 10 mg/kg) were intraperitoneally injected to C57BL/6 male mice 48, 24, 1 h prior to and 24 h after 9.0Gy TBI. The results showed that UroA markedly upregulated the survival of irradiated mice, especially at concentration of 2 mg/kg. UroA improved the intestine morphology architecture and the regeneration ability of enterocytes in irradiated mice. Then, UroA significantly decreased the apoptosis of enterocytes induced by radiation. Additionally, 16S rRNA sequencing analysis showed the effect of UroA is associated with the recovery of the IR‐induced intestinal microbacteria profile changes in mice. Therefore, our results determinated UroA could be developed as a potential candidate for radiomitigators in radiotherapy and accidental nuclear exposure. And the beneficial functions of UroA might be associated with the inhibition of p53‐mediated apoptosis and remodelling of the gut microbes. [ABSTRACT FROM AUTHOR]

Introduction: This study characterized Vibrio alginolyticus isolated from seafood and freshwater products in China (2020)., Methods and Results: In total, 122 (95.31%) V. alginolyticus isolates were resistant to at least 1 antibiotic category, and 2 (1.56%) isolates were resistant to at least 3 antibiotic categories and belong to multi-drug resistance (MDR) isolates. A high prevalence rate was observed to be blaCARB (98.04%) encoding beta-lactam resistance, followed by tet (97.06%) encoding tetracycline resistance and fos (4.90%) encoding resistance to fosfomycin. Among the 57 V. alginolyticus isolates, the commonest virulence genes were type III secretion system translocated gene vopD , vopB , and vcrH (54.4%, 31/57), type III secretion system regulated gene tyeA (54.39%), followed by vscI and vscF (50.88%) encoded type III secretion system inner rod protein and needle protein, respectively. Multilocus sequence typing (MLST) showed considerable genetic diversity, with 34 distinct sequence types (STs) identified among 55 isolates. ST421 ( n  = 5), ST166 ( n  = 4), ST523 ( n  = 3), ST516 ( n  = 3), and ST507 ( n  = 3) were dominant STs among 55 V. alginolyticus isolates., Discussion: These findings highlight the widespread occurrence of V. alginolyticus in both freshwater and seafood products, underscoring the critical need for vigilant monitoring of these bacteria. Such measures are essential for ensuring effective food safety management and safeguarding public health., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sun, Yan, Yan, Li, Li, Yan, Yang, Peng, Yang, Sun, Xu, Dong and Bai.)

Background: Staphylococcal cassette chromosome mec (SCCmec) elements are highly diverse and have been classified into 14 types. Novel SCCmec variants have been frequently detected from humans and animals but rarely from food., Objectives: To characterize a novel SCCmec type and two SCCmec variants identified from food-associated MRSA in China., Methods: Three MRSA (NV_1, NT_611 and NT_8) collected from retail foods in China were subjected to WGS and the SCCmec elements were determined., Results: The novel SCCmecXV identified in NV_1 carried the mec gene complex class A (mecI-mecR1-mecA-IS431) and the ccr gene complex 7 (ccrA1B6), and a Tn558-mediated phenicol exporter gene fexA was detected in this SCCmecXV cassette. The pseudo-SCCmec elements ΨSCCmecNT_611 and ΨSCCmecNT_8 showed a truncated SCCmec pattern, carrying the class C2 mec gene complex but missing the ccr genes. The ΨSCCmecNT_611 element shared more similarities with those of Staphylococcus haemolyticus (AB478934.1) and carried a heavy metal resistance gene cluster cadD-cadX-arsC-arsB-arsR-copA. The ΨSCCmecNT_8 MRSA exhibited a highly resistant phenotype, showing the absence of a 19.3 kb segment compared with the reference SCCmecXII element (CP019945.1). Notably, a 46 kb region containing multiple transposons encoding antimicrobial or metal resistance genes flanked by IS431 or IS256 was identified ∼30 kb downstream from the mec gene complex in ΨSCCmecNT_8, which might explain such high resistance in MRSA NT_8., Conclusions: Our finding of novel and pseudo-SCCmec elements reflected the ongoing intra/interspecies genetic rearrangements in staphylococci. Further study will be needed to investigate the biological significance and prevalence of those SCCmec variants along the food chain., (© The Author(s) 2022. Published by Oxford University Press on behalf of British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)