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ObjectiveTo understand the contamination status， virulence gene carrying status and pulsed field gel electrophoresis （PFGE） molecular typing of Cronobacter sakazakii in food in Shanxi Province.MethodsThe strain was identified by Antu mass spectrometry detection system. Four virulence genes， ompX， cpa， hly and sip， were detected by fluorescent PCR， and PFGE molecular typing was performed.ResultsThe results showed that in 1 050 samples from 2013 to 2022， 80 strains of Cronobacter sakazakii were isolated， and the total detection rate was 7.62%. The detection rates of four virulence genes were ompX 86.25%， cpa 85.00%， hly 98.75% and sip 86.25%， respectively. PFGE genotype was divided into 67 gene profiles with similarity ranging from 43.7% to 100%， showing great genetic diversity among strains.The strains of different origin and different manufacturers were scattered， and only a few strains showed genetic correlation.ConclusionThe results of this study can provide data support for the risk status and typing of Cronobacter sakazakii in food from Shanxi Province， It is necessary to strengthen assessment and multi-link prevention and control.

Chronic kidney disease （CKD） has become a global public health event. CKD may eventually progress into end-stage renal disease （ESRD）. Renal interstitial fibrosis （RIF） is the common pathway for the progression from CKD into ESRD. Due to the complex pathogenesis, there is currently no effective treatment for RIF. Recent studies have shown that exosomes play an important role in the occurrence and development of a variety of kidney diseases. In this article, the latest research progress on the role of exosomes in the pathogenesis of RIF was reviewed, and the application prospect of exosomes in the diagnosis and treatment of RIF was investigated.

Propylparaben (PrP) is widely applied in food, pharmaceuticals and personal care products as preservatives, and the extensive usage of PrP has posed potential threat to aquatic ecosystem. In this study, wild-sourced female mosquitofish were treated with different concentrations of PrP (0.15, 6.0 and 240.0 µg⋅L-1) for 4 d and 16 d respectively. The tissue sections as well as mRNA expression changes of antioxidant and endocrine-related genes from the brain, gills and liver, were analyzed to investigate the toxicological effects of PrP on mosquitofish. The results showed that different PrP exposure time resulted in varying degrees of damage to the gills and liver of mosquitofish. With the extension of exposure time, the expression of antioxidant-related genes in the brain was up-regulated, whereas the expression of antioxidant-related genes in the gills, as well as cat and cyp4501a genes in the liver, were down-regulated, and the oxidative stress response in the gills and liver gradually weakened. When female mosquitofish were exposed to PrP for 4 d, the endocrine-related genes in the brain increased firstly and then decreased with increasing PrP dose, while in the 16-d-PrP-exposure groups, the genes showed an increased trend compared with that of the control. After 4 d of PrP exposure, a significant difference was observed in the expression of the vtgB gene within liver tissues between the 0.15 µg⋅L-1 PrP group and the control group, as well as in the expression of the arβ gene within liver tissues between the 240.0 µg⋅L-1 PrP group and the control group; however, no significant differences were found in other endocrine-related genes among different PrP groups and the control group. When the exposure time was extended to 16 d, the expression of era, erβ, arα, arβ, vtgC and vtgB genes in the liver was all up-regulated in the three treatment groups, indicating that PrP had estrogenic effects on mosquitofish. This study revealed the toxic damage, oxidative stress and endocrine disrupting effects of PrP on mosquitofish, through the phenotypic variations in tissues and changes in mRNA expression of key functional genes, which will provide a scientific basis for the potential health risk assessment and safe application of PrP. [ABSTRACT FROM AUTHOR]

In order to increase the output of high-grade camel hair products and meet the increasing social demand, the camel hair fiber was treated with sodium bisulfite (NaHSO3) to explore the feasibility of hair refinement. The results show that NaHSO3 solution can open the disulfide bond of camel hair, resulting in an increase of elongation at break upto 150%. Infrared spectrum shows that hydrogen bond of camel hair plays a role of temporary shape fixation and stimulus recovery in cyclic tensile test. In addition, the water and the hydrogen bonding interaction can lead to temporary shape of camel hair macromolecular response rates above 90%, and the temporary shape recovery rate of camel hair after NaHSO3 treatment is reduced to 60% and 50% due to the partial destruction of disulfide bond and hydrogen bond. The shape memory property of the treated camel hair is weakened, which is conducive to the slenderation process, and the shape of the drawn camel hair is stable and solidified, thereby to increase the production amount of super-fine camel hair. [ABSTRACT FROM AUTHOR]

Anthrax is a highly lethal infectious disease caused by the spore-forming bacterium Bacillus anthracis. The major virulence factor of B. anthracis consists of protective antigen (PA), lethal factor (LF) and edema factor (EF). PA binds with LF to form lethal toxin (LT), and PA binds with EF to form edema toxin (ET). Antibiotics is hard to work in advanced anthrax infections, because injuries and deaths of the infected are mainly caused by lethal toxin (LT). Thus, the therapeutic neutralizing antibody is the most effective treatment of anthrax. Currently most of the anthrax toxin antibodies are monoclonal antibodies (MAbs) for PA and US FDA has approved ABTHRAX humanized PA monoclonal antibody for the treatment of inhalational anthrax. Once B. anthracis was artificially reconstructed or PA had mutations within recognized neutralization epitopes, anti-PA MAbs would no longer be effective. Therefore, anti-LF MAbs is an important supplement for anthrax treatment. Most of the anti-LF antibodies are murine or chimeric antibodies. By contrast, fully human MAbs can avoid the high immunogenicity of murine antibodies. First, we used LF to immunize the transgenic mice and used fluorescent cell sorting to get antigen-specific memory B cells from transgenic mice spleen lymphocytes. By single cell PCR method, we quickly found two strains of anti-LF MAbs with binding activity, 1D7 and 2B9. Transiently transfected Expi 293F cells to obtain MAbs protein after purification. Both 1D7 and 2B9 efficiently neutralized LT in vitro, and had good synergistic effect when mixed with anti-PA MAbs. In summary, combining the advantages of transgenic mice, fluorescent cell sorting and single-cell PCR methods, this study shows new ideas and methods for the rapid screening of fully human monoclonal antibodies.

Objective: To express human-mouse chimeric antibody against Yersinia pestis F1 capsular antigen (F1 antigen) and analyze its biological activities., Methods: The heavy chain gene of the chimeric antibody was obtained by fusing the variable region gene of the mouse mAb heavy chain with human IgG1 constant region gene. The light chain gene of the chimeric antibody was obtained by fusing the variable region gene of the mouse mAb light chain with the human kappa constant region gene. Both the heavy and light chain genes of the chimeric antibody were further verified by sequencing. The chimeric antibody heavy and light chain genes were inserted into EcoR I/Not I of pcDNA3.1 (+) to construct expression plasmids termed pcDNA3.1-L and pcDNA3.1-H, respectively. Then, two plasmids were mixed and transfected into CHO-S cells. Finally, the stable cell clone secreting chimeric antibody was obtained by G418 selection. The culture supernatants of serum-free medium were collected and the chimeric antibody was purified by MabSelect SuRe affinity chromatography. The purified chimeric antibody was analyzed by SDS-PAGE, Western blotting, ELISA and evaluated in the protective effect in vivo., Results: PCR and sequencing analysis proved that plasmids pcDNA3.1-H and pcDNA3.1-L were correctly constructed. Dot blot showed that a cell line with high-level expression of chimeric antibody was obtained. SDS-PAGE and western blot showed that the chimeric antibody was successfully purified. ELISA showed that the chimeric antibody could specifically bind to F1 antigen. In vivo activity assay showed that 80% BALB/c mice treated with the chimeric antibody survived from 36 MLD virulent Yersinia pestis., Conclusion: The chimeric antibody against F1 antigen with neutralizing activity was successfully expressed in CHO-S cells, which laid a foundation for the preparation of anti-plague passive immunity agents.

Objective: Set an objectively scientific foundation for name, diagnosis, therapy and assessment of mutational falsetto., Method: We analyzed the acoustic samples of patients by computer, 15 patients, 12 normal young men, 13 normal young women and 12 normal children were asked to produced comfortable modal vowel/a/ and /i/, sustained 3 seconds. The falsetto /a/ and /i/ were only collected from young men and women. The acoustic parameters were compared between any two groups., Result: Both vowel /a/ and /i/, the fundamental frequency, highest fundamental frequency and lowest fundamental frequency of patients are closed to young women's (P > 0.05). Jitter percent and pitch perturbation quotient is significantly higher than other groups (P < 0.05). Fundamental frequency variation has no significant difference between groups, but the patients mean is higher than others. Shimmer percent and peak-to-peak amplitude variation of patients' vowel /a/ are distinctly greater than other groups. Amplitude perturbation quotient of vowel /a/ has no significance between groups, but the patients' group is higher than others. Shimmer percent, peak-to-peak amplitude variation and amplitude perturbation of vowel /i/ has no significant difference between most groups, but the results of patients are the biggest. Noise to harmonic ratio of falsetto is the lowest among all groups. Voice turbulence index of the patients and falsetto is lower than that of others. Soft phonation index of patients is higher than other groups and near to falsetto, vowel /i/ is more significant than /a/. The children falsetto and the patients have voice break., Conclusion: Mutational "falsetto" is not really falsetto, but rather similar to female's voice. To lower fundamental frequency and improve chest resonance is the key of treatment. Both psychotherapy and voice training are important. We can try to use rigid phonation to treat patients.