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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]

Fresh Milk Bar (FMB), an emerging dairy retail franchise, is used to instantly produce and sell pasteurized milk and other dairy products in China. However, the quality and safety of pasteurized milk in FMB have received little attention. The objective of this study was to investigate the prevalence, antimicrobial resistance, and virulence genes of Escherichia coli, Staphylococcus aureus, and Streptococcus in 205 pasteurized milk samples collected from FMBs in China. Four (2.0%) isolates of E. coli, seven (3.4%) isolates of S. aureus, and three (1.5%) isolates of Streptococcus agalactiae were isolated and identified. The E. coli isolates were resistant to amikacin (100%), streptomycin (50%), and tetracycline (50%). Their detected resistance genes include aac(3)-III (75%), blaTEM (25%), aadA (25%), aac(3)-II (25%), catI (25%), and qnrB (25%). The S. aureus isolates were mainly resistant to penicillin G (71.4%), trimethoprim-sulfamethoxazole (71.4%), kanamycin (57.1%), gentamicin (57.1%), amikacin (57.1%), and clindamycin (57.1%). blaZ (42.9%), mecA (28.6%), ermB (14.3%), and ermC (14.3%) were detected as their resistance genes. The Streptococcus strains were mainly resistant to tetracycline (66.7%) and contained the resistance genes pbp2b (33.3%) and tetM (33.3%). The virulence genes eae and stx2 were only found in one E. coli strain (25%), sec was detected in two S. aureus strains (28.6%), and bca was detected in one S. agalactiae strain (33.3%). The results of this study indicate that bacteria with drug resistance and virulence genes isolated from the pasteurized milk of FMB are a potential risk to consumers' health. [ABSTRACT FROM AUTHOR]

The tigecycline resistance gene tet (X4) has been widely reported in animals and animal products in some Asian countries including China in recent years but only sporadically detected in human. In this study, we investigated the prevalence and genetic features of tet (X4)-positive clinical E. coli strains. A total of 462 fecal samples were collected from patients in four hospitals located in four provinces in China in 2023. Nine tet (X4)-positive E. coli strains were isolated and subjected to characterization of their genetic and phenotypic features by performing antimicrobial susceptibility test, whole-genome sequencing, bioinformatic and phylogenetic analysis. The majority of the test strains were found to exhibit resistance to multiple antimicrobial agents including tigecycline but remained susceptible to colistin and meropenem. A total of seven different sequence types (STs) and an unknown ST type were identified among the nine tet (X4)-positive strains. Notably, the tet (X4) gene in six out of these nine tet (X4)-positive E. coli strains was located in a IncFIA-HI1A-HI1B hybrid plasmid, which was an tet (X4)-bearing epidemic plasmid responsible for dissemination of the tet (X4) gene in China. Furthermore, the tet (X4) gene in four out of nine tet (X4)-positive E. coli isolates could be successfully transferred to E. coli EC600 through conjugation. In conclusion, this study characterized the epidemic tet (X4)-bearing plasmids and tet (X4)-associated genetic environment in clinical E. coli strains, suggested the importance of continuous surveillance of such tet (X4)-bearing plasmids to control the increasingly widespread dissemination of tigecycline-resistant pathogens in clinical settings in China. [ABSTRACT FROM AUTHOR]

The thin-walled grid plate is one of the passive aerodynamic measures for suppressing vortex-induced vibration (VIV) of twin-box girder bridges. However, the effectiveness of the grid plate in aerodynamic stabilization is not fully known. In this study, we compared the flutter performance and aerostatic performance, as well as VIV performance, of a twin-box girder suspension bridge with four different grid porosities, through a series of wind-tunnel tests and three-dimensional nonlinear finite-element analyses. Results show that a thin-walled grid plate with larger grid porosity could effectively improve both the flutter performance and aerostatic performance of the bridge. This was particularly true with a plate of 100% grid porosity. Based on the 3D nonlinear bridge finite-element model, the flutter divergence mode of a 3D bridge is caused mainly by symmetrical vertical bending as grid porosity increases. Furthermore, the torsional VIV performance of a twin-box girder with smaller grid porosity is superior to those with larger grid porosity, and the application of grid plates of 30% and 50% porosity can result in VIV performance that complies fully with both the wind-resistance specification of China and the Sperling indicator. • 3D nonlinear flutter, VIV and stationary aerodynamic performance of a super longs-span suspension bridge with four grid porosities were studied to identify the aerodynamic optimal of grid plates on the twin-box girder. • A grid plate with larger grid porosity effectively improves the flutter and stationary aerodynamic performance. • The flutter divergence in the coupled vibration with larger grid porosity is caused mainly by the symmetrical vertical bending mode. • Only the torsional VIV displacements with 30% and 50% grid porosities satisfy the requirements of two stipulates. [ABSTRACT FROM AUTHOR]

Multiple myeloma (MM) is a malignant disorder characterised by progressive immune dysregulation. The importance of programmed cell death protein 1 (PD-1)/programmed cell death ligand 1 (PD-L1) in MM has been documented in various populations, but studies have been limited to the Chinese cohort. In the present study, we examined the role of PD-1/PDL-1 in large cohorts of Chinese patients with MM and healthy controls to reveal a possible association with MM. Three hundred thirty-four MM patients and 202 healthy age-sex-matched subjects were enrolled in the present study. Serum levels of PD-1 and PD-L1 were quantified by ELISA. Percentages of T cells (CD4 + and CD8 + T cells) expressing PD-1 receptor were assessed by flow cytometry. Variants in PD-L1 (rs4143815) and PD-1 gene (rs2227981, rs2227982, rs7421861 and rs11568821) were genotyped by PCR-RFLP method. Patients with multiple myeloma had higher levels of PD-1 and PDL-1 than healthy controls, indicating an important role for programmed cell death protein-1 and its ligand in the pathogenesis of MM. T cells expressing PD-1 receptors were also significantly higher in MM patients than in controls. Mutants for PD-L1 (rs4143815) and PD-1 (rs2227982 and rs7421861) polymorphisms were significantly more common in MM than in HC. Interestingly, PD-L1 (rs4143815) and PD-1 (rs2227982 and rs7421861) variants were linked to higher sPD-L1 and sPD-1 levels, respectively. PD-1/PD-L1 levels are significantly higher in MM patients and could be a promising biomarker for the disease. Variants of PD-L1 and PD-1 are linked to serum-soluble proteins and are associated with the development of MM.

Background: Early-onset scoliosis (EOS), defined by an onset age of scoliosis less than 10 years, conveys significant health risk to affected children. Identification of the molecular aetiology underlying patients with EOS could provide valuable information for both clinical management and prenatal screening., Methods: In this study, we consecutively recruited a cohort of 447 Chinese patients with operative EOS. We performed exome sequencing (ES) screening on these individuals and their available family members (totaling 670 subjects). Another cohort of 13 patients with idiopathic early-onset scoliosis (IEOS) from the USA who underwent ES was also recruited., Results: After ES data processing and variant interpretation, we detected molecular diagnostic variants in 92 out of 447 (20.6%) Chinese patients with EOS, including 8 patients with molecular confirmation of their clinical diagnosis and 84 patients with molecular diagnoses of previously unrecognised diseases underlying scoliosis. One out of 13 patients with IEOS from the US cohort was molecularly diagnosed. The age at presentation, the number of organ systems involved and the Cobb angle were the three top features predictive of a molecular diagnosis., Conclusion: ES enabled the molecular diagnosis/classification of patients with EOS. Specific clinical features/feature pairs are able to indicate the likelihood of gaining a molecular diagnosis through ES., Competing Interests: Competing interests: JRL has stock ownership in 23andMe, is a paid consultant for Regeneron Pharmaceuticals and Novartis and is a coinventor on multiple US and European patents related to molecular diagnostics for inherited neuropathies, eye diseases and bacterial genomic fingerprinting. The Department of Molecular and Human Genetics at Baylor College of Medicine derives revenue from the chromosomal microarray analysis (by comparative genomic hybridisation microarray and/or single-nucleotide polymorphism arrays), clinical exome sequencing and whole-genome sequencing offered in the Baylor Genetics Laboratory (http://bmgl.com)., (© Author(s) (or their employer(s)) 2021. No commercial re-use. See rights and permissions. Published by BMJ.)

Heat stress decreases milk yield and deleteriously alters milk composition. Reduced feed intake partially explains some of the consequences of heat stress, but metabolic changes in the mammary tissue and liver associated with milk synthesis have not been thoroughly evaluated. In the current study, changes of protein abundance in the mammary tissue and liver between heat-stressed cows with ad libitum intake and pair-fed thermal neutral cows were investigated using the iTRAQ proteomic approach. Most of the differentially expressed proteins from mammary tissue and liver between heat-stressed and pair-fed cows were involved in Gene Ontology category of protein metabolic process. Pathway analysis indicated that differentially expressed proteins in the mammary tissue were related to pyruvate, glyoxylate and dicarboxylate metabolism pathways, while those in the liver participated in oxidative phosphorylation and antigen processing and presentation pathways. Several heat shock proteins directly interact with each other and were considered as central "hubs" in the protein interaction network. These findings provide new insights to understand the turnover of protein biosynthesis pathways within hepatic and mammary tissue that likely contribute to changes in milk composition from heat-stressed cows., Competing Interests: The authors have declared that no competing interests exist.

Background: To validate iScore and PLAN score in acute anterior circulation large vessel occlusion stroke patients undergoing thrombectomy., Methods: iScore and PLAN score were calculated for consecutive acute ischemic stroke undergoing thrombectomy were included and death at 1 month and death at 3 months were recorded. The area under the receiver operating characteristic curve was used to assess the discrimination ability of the scales for death., Results: Two hundred and twenty-nine patients were included, 25.3% (58 of 229) of patient died at 1 month after thrombectomy and 25.8% (59 of 229) of them died at 3 months after thrombectomy. The receiver operator curve analysis found that iScore (area under the curve [AUC] = .76, 95% confidence interval [CI] .69-.83) was numerically better than PLAN score (AUC = .73, 95% CI .66-.81) for predicting death at day 90. The cut-off for iScore is 193, with sensitivity 64%, specificity 79%, positive predictive value 75% and negative predictive value 69%., Conclusions: The iScore scale is a valid predictive tool for death in anterior circulation large vessel occlusions undergoing thrombectomy., (Copyright © 2018. Published by Elsevier Inc.)

Background: Milk composition and its fatty acid profile have received much attention with respect to improving human health. However, limited work has been conducted to assess the composition of milk fat in China, which is the third largest producer of milk in the world. In this study the effects of geographical region and seasonal changes (spring and summer) on the fatty acid composition of milk samples collected from six Chinese farms were investigated., Results: Milk fat and protein contents, as well as some individual fatty acids and five fatty acid groups, were found to be unaffected by season, but they did show significant differences by geographical region. Levels of milk cis-9, trans-11 conjugated linoleic acid decreased in summer and increased in spring, increased in north (Hohhot), northeast (Harbin), north centre (Beijing) and northwest (Xi'an) China and decreased in far northwest (Urumqi) and east (Chuzhou) China. Monounsaturated fatty acids increased in east and northwest China and decreased in northeast China, while polyunsaturated fatty acids increased in far northwest and north centre China and decreased in northeast China., Conclusion: This study provides relevent information that contributes to the understanding of parameters affecting variability of milk fatty acid profiles., (© 2012 Society of Chemical Industry.)