1.Hepatitis C virus infection:surveillance report from China Healthcare-as-sociated Infection Surveillance System in 2020
Xi-Mao WEN ; Nan REN ; Fu-Qin LI ; Rong ZHAN ; Xu FANG ; Qing-Lan MENG ; Huai YANG ; Wei-Guang LI ; Ding LIU ; Feng-Ling GUO ; Shu-Ming XIANYU ; Xiao-Quan LAI ; Chong-Jie PANG ; Xun HUANG ; An-Hua WU
Chinese Journal of Infection Control 2024;23(1):1-8
Objective To investigate the infection status and changing trend of hepatitis C virus(HCV)infection in hospitalized patients in medical institutions,and provide reference for formulating HCV infection prevention and control strategies.Methods HCV infection surveillance results from cross-sectional survey data reported to China Healthcare-associated Infection(HAI)Surveillance System in 2020 were summarized and analyzed,HCV positive was serum anti-HCV positive or HCV RNA positive,survey result was compared with the survey results from 2003.Results In 2020,1 071 368 inpatients in 1 573 hospitals were surveyed,738 535 of whom underwent HCV test,4 014 patients were infected with HCV,with a detection rate of 68.93%and a HCV positive rate of 0.54%.The positive rate of HCV in male and female patients were 0.60%and 0.48%,respectively,with a statistically sig-nificant difference(x2=47.18,P<0.001).The HCV positive rate in the 50-<60 age group was the highest(0.76%),followed by the 40-<50 age group(0.71%).Difference among all age groups was statistically signifi-cant(x2=696.74,P<0.001).In 2003,91 113 inpatients were surveyed.35 145 of whom underwent HCV test,resulting in a detection rate of 38.57%;775 patients were infected with HCV,with a positive rate of 2.21%.In 2020,HCV positive rates in hospitals of different scales were 0.46%-0.63%,with the highest in hospital with bed numbers ranging 600-899.Patients'HCV positive rates in hospitals of different scales was statistically signifi-cant(X2=35.34,P<0.001).In 2020,12 provinces/municipalities had over 10 000 patients underwent HCV-rela-ted test,and HCV positive rates ranged 0.19%-0.81%,with the highest rate from Hainan Province.HCV posi-tive rates in different departments were 0.06%-0.82%,with the lowest positive rate in the department of pedia-trics and the highest in the department of internal medicine.In 2003 and 2020,HCV positive rates in the depart-ment of infectious diseases were the highest,being 7.95%and 3.48%,respectively.Followed by departments of orthopedics(7.72%),gastroenterology(3.77%),nephrology(3.57%)and general intensive care unit(ICU,3.10%)in 2003,as well as departments of gastroenterology(1.35%),nephrology(1.18%),endocrinology(0.91%),and general intensive care unit(ICU,0.79%)in 2020.Conclusion Compared with 2003,HCV positive rate decreased significantly in 2020.HCV infected patients were mainly from the department of infectious diseases,followed by departments of gastroenterology,nephrology and general ICU.HCV infection positive rate varies with gender,age,and region.
2.National bloodstream infection bacterial resistance surveillance report (2022) : Gram-negative bacteria
Zhiying LIU ; Yunbo CHEN ; Jinru JI ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Haifeng MAO ; Hui DING ; Pengpeng TIAN ; Jiangqin SONG ; Yongyun LIU ; Jiliang WANG ; Yan JIN ; Yuanyuan DAI ; Yizheng ZHOU ; Yan GENG ; Fenghong CHEN ; Lu WANG ; Yanyan LI ; Dan LIU ; Peng ZHANG ; Junmin CAO ; Xiaoyan LI ; Dijing SONG ; Xinhua QIANG ; Yanhong LI ; Qiuying ZHANG ; Guolin LIAO ; Ying HUANG ; Baohua ZHANG ; Liang GUO ; Aiyun LI ; Haiquan KANG ; Donghong HUANG ; Sijin MAN ; Zhuo LI ; Youdong YIN ; Kunpeng LIANG ; Haixin DONG ; Donghua LIU ; Hongyun XU ; Yinqiao DONG ; Rong XU ; Lin ZHENG ; Shuyan HU ; Jian LI ; Qiang LIU ; Liang LUAN ; Jilu SHEN ; Lixia ZHANG ; Bo QUAN ; Xiaoping YAN ; Xiaoyan QI ; Dengyan QIAO ; Weiping LIU ; Xiusan XIA ; Ling MENG ; Jinhua LIANG ; Ping SHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2024;17(1):42-57
Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of national bloodstream infection Bacterial Resistant Investigation Collaborative System(BRICS)were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute(CLSI). WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:During the study period,9 035 strains of Gram-negative bacteria were collected from 51 hospitals,of which 7 895(87.4%)were Enterobacteriaceae and 1 140(12.6%)were non-fermenting bacteria. The top 5 bacterial species were Escherichia coli( n=4 510,49.9%), Klebsiella pneumoniae( n=2 340,25.9%), Pseudomonas aeruginosa( n=534,5.9%), Acinetobacter baumannii complex( n=405,4.5%)and Enterobacter cloacae( n=327,3.6%). The ESBLs-producing rates in Escherichia coli, Klebsiella pneumoniae and Proteus spp. were 47.1%(2 095/4 452),21.0%(427/2 033)and 41.1%(58/141),respectively. The prevalence of carbapenem-resistant Escherichia coli(CREC)and carbapenem-resistant Klebsiella pneumoniae(CRKP)were 1.3%(58/4 510)and 13.1%(307/2 340);62.1%(36/58)and 9.8%(30/307)of CREC and CRKP were resistant to ceftazidime/avibactam combination,respectively. The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)complex was 59.5%(241/405),while less than 5% of Acinetobacter baumannii complex was resistant to tigecycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa(CRPA)was 18.4%(98/534). There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of main Gram-negative bacteria resistance among different regions,with statistically significant differences in the prevalence of CRKP and CRPA( χ2=20.489 and 20.252, P<0.001). The prevalence of CREC,CRKP,CRPA,CRAB,ESBLs-producing Escherichia coli and Klebsiella pneumoniae were higher in provinicial hospitals than those in municipal hospitals( χ2=11.953,81.183,10.404,5.915,12.415 and 6.459, P<0.01 or <0.05),while the prevalence of CRPA was higher in economically developed regions(per capita GDP ≥ 92 059 Yuan)than that in economically less-developed regions(per capita GDP <92 059 Yuan)( χ2=6.240, P=0.012). Conclusions:The proportion of Gram-negative bacteria in bloodstream infections shows an increasing trend,and Escherichia coli is ranked in the top,while the trend of CRKP decreases continuously with time. Decreasing trends are noted in ESBLs-producing Escherichia coli and Klebsiella pneumoniae. Low prevalence of carbapenem resistance in Escherichia coli and high prevalence in CRAB complex have been observed. The composition ratio and antibacterial spectrum of bloodstream infections in different regions of China are slightly different,and the proportion of main drug resistant bacteria in provincial hospitals is higher than those in municipal hospitals.
3.Determining Whether an Individual is 18 Years or Older Based on the Third Molar Root Pulp Visibility in East China
De-Min HUO ; Kai-Jun MA ; Jing-Lan XU ; Xu SONG ; Xiao-Yan MAO ; Xia LIU ; Kai-Fang ZHAO ; Jian ZHANG ; Meng DU
Journal of Forensic Medicine 2024;40(2):149-153
Objective To investigate the age-related changes of the mandibular third molar root pulp visibility in individuals in East China,and to explore the feasibility of applying this method to deter-mine whether an individual is 18 years or older.Methods A total of 1 280 oral panoramic images were collected from the 15-30 years old East China population,and the mandibular third molar root pulp visibility in all oral panoramic images was evaluated using OLZE 0-3 four-stage method,and the age distribution of the samples at each stage was analyzed using descriptive statistics.Results Stages 0,1,2 and 3 first appeared in 16.88,19.18,21.91 and 25.44 years for males and in 17.47,20.91,22.01 and 26.01 years for females.In all samples,individuals at stages 1 to 3 were over 18 years old.Conclusion It is feasible to determine whether an individual in East China is 18 years or older based on the mandibular third molar root pulp visibility on oral panoramic images.
4.Development and Challenges of Additive Manufactured Customized Implant
Changning SUN ; Zijie MENG ; Ling WANG ; Jiankang HE ; Qin LIAN ; Lin GAO ; Xiao LI ; Mao MAO ; Hui ZHU ; Dichen LI
Chinese Journal of Medical Instrumentation 2024;48(3):237-244
Additive manufacturing(3D printing)technology aligns with the direction of precision and customization in future medicine,presenting a significant opportunity for innovative development in high-end medical devices.Currently,research and industrialization of 3D printed medical devices mainly focus on nondegradable implants and degradable implants.Primary areas including metallic orthopaedic implants,polyether-ether-ketone(PEEK)bone implants,and biodegradable implants have been developed for clinical and industrial application.Recent research achievements in these areas are reviewed,with a discussion on the additive manufacturing technologies and applications for customized implants.Challenges faced by different types of implants are analyzed from technological,application,and regulatory perspectives.Furthermore,prospects and suggestions for future development are outlined.
5.Experimental study on the inhibition of the NLRP3 signaling pathway with Shengsan Jiedu Huayu decoction to alleviate inflammatory injury in rats with acute-on-chronic liver failure
Xiao LIU ; Jianlin MENG ; Minggang WANG ; Dewen MAO ; Ming DAI
Chinese Journal of Hepatology 2024;32(4):354-362
Objective:To observe the therapeutic effect of Shengsan Jiedu Huayu decoction in alleviating inflammatory liver injury in rats with acute-on-chronic liver failure (ACLF) and its effect on the activation intensity for the NLRP3 signaling pathway.Methods:63 SD rats were randomly divided into a blank group, a model group, and low-, medium-, and high-dose groups of Shengsan Jiedu Huayu decoction (7.29 g/kg/d, 14.58 g/kg/d, and 29.16 g/kg/d). The ACLF rat model was replicated using carbon tetrachloride combined with d-galactosamine and lipopolysaccharide. Different dose gradients of the Shengsan Jiedu Huayu decoction were used for a five-day intervention treatment, and then rat serum and tissue samples were collected. A biochemical analyzer was used to detect the serum levels of ALT, AST, and TBIL in rats. ELISA was used to detect serum IL-18 and IL-1β content. HE staining was used to observe histomorphological changes in liver tissue. Immunohistochemistry was used to detect GSDMD expression in liver tissue. Western blot and PCR were used to detect NLRP3, Caspase1, ASC, TLR4, IL-1β, IL-18 protein, and mRNA expression levels.The groups were compared using analysis of variance and the rank-sum test.Results:Compared with the blank group, the model group’s rat liver tissue was severely injured. Serum levels of ALT, AST, and TBIL, inflammatory factors IL-1β and IL-18, and the GSDMD protein expression level, NLRP3 expression level, TLR4, caspase 1, ASC, IL-1β, IL-18 protein, and mRNA ( P<0.01) were all significantly increased in the model than the blank group ( P<0.01). Additionally, compared with the model group, the low-, medium-, and high-dose groups of Shengsan Jiedu Huayu decoction had improved liver tissue injury in ACLF rats, while the serum levels of ALT, AST, TBIL, IL-1β, IL-18, liver tissue GSDMD protein, NLRP3, TLR4, caspase 1, and ASC expressions were all lower in the different dose gradients of the Shengsan Jiedu Huayu decoction than the model group, with the most evident reduction in the high-dose group ( P<0.01). Conclusion:Shengsan Jiedu Huayu decoction can weaken the activation intensity of the NLRP3 signaling pathway, alleviate liver tissue pathological injury, reduce inflammatory factor release, and alleviate inflammatory liver injury in ACLF rats.
6.Considerations for cardiac safety risk management in phase Ⅰ clinical trials of sphingosine phosphate receptor 1 modulators
Xiao-Meng MAO ; Jing ZHANG ; Hai-Jing YANG ; Jing-Jing WANG
The Chinese Journal of Clinical Pharmacology 2024;40(11):1646-1649
Sphingosine 1-phosphate receptor 1(S1PR1)is currently a popular research target for the treatment of immune-related diseases,but it also has potential cardiac safety risks.This article summarizes the experience of the completed phase Ⅰ clinical trial of S1PR1 innovative drug and discusses the necessity and implementation points of cardiac safety risk management and control in the phase Ⅰ clinical trial of S1PR1 innovative drug by summarizing the experience of the completed phase Ⅰclinical trial of S1PR1 innovative drug,combined with the guiding principles of risk identification and control strategy for early clinical trial and clinical evaluation of drug QT at home and abroad,for the reference of the industry.
7.National bloodstream infection bacterial resistance surveillance report(2022): Gram-positive bacteria
Chaoqun YING ; Yunbo CHEN ; Jinru JI ; Zhiying LIU ; Qing YANG ; Haishen KONG ; Haifeng MAO ; Hui DING ; Pengpeng TIAN ; Jiangqin SONG ; Yongyun LIU ; Jiliang WANG ; Yan JIN ; Yuanyuan DAI ; Yizheng ZHOU ; Yan GENG ; Fenghong CHEN ; Lu WANG ; Yanyan LI ; Dan LIU ; Peng ZHANG ; Junmin CAO ; Xiaoyan LI ; Dijing SONG ; Xinhua QIANG ; Yanhong LI ; Qiuying ZHANG ; Guolin LIAO ; Ying HUANG ; Baohua ZHANG ; Liang GUO ; Aiyun LI ; Haiquan KANG ; Donghong HUANG ; Sijin MAN ; Zhuo LI ; Youdong YIN ; Kunpeng LIANG ; Haixin DONG ; Donghua LIU ; Hongyun XU ; Yinqiao DONG ; Rong XU ; Lin ZHENG ; Shuyan HU ; Jian LI ; Qiang LIU ; Liang LUAN ; Jilu SHEN ; Lixia ZHANG ; Bo QUAN ; Xiaoping YAN ; Xiaoyan QI ; Dengyan QIAO ; Weiping LIU ; Xiusan XIA ; Ling MENG ; Jinhua LIANG ; Ping SHEN ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2024;17(2):99-112
Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical Gram-positive bacteria isolates from bloodstream infections in China in 2022.Methods:The clinical isolates of Gram-positive bacteria from blood cultures in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System(BRICS)were collected during January 2022 to December 2022. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute(CLSI). WHONET 5.6 and SPSS 25.0 software were used to analyze the data.Results:A total of 3 163 strains of Gram-positive pathogens were collected from 51 member units,and the top five bacteria were Staphylococcus aureus( n=1 147,36.3%),coagulase-negative Staphylococci( n=928,29.3%), Enterococcus faecalis( n=369,11.7%), Enterococcus faecium( n=296,9.4%)and alpha-hemolyticus Streptococci( n=192,6.1%). The detection rates of methicillin-resistant Staphylococcus aureus(MRSA)and methicillin-resistant coagulase-negative Staphylococci(MRCNS)were 26.4%(303/1 147)and 66.7%(619/928),respectively. No glycopeptide and daptomycin-resistant Staphylococci were detected. The sensitivity rates of Staphylococcus aureus to cefpirome,rifampin,compound sulfamethoxazole,linezolid,minocycline and tigecycline were all >95.0%. Enterococcus faecium was more prevalent than Enterococcus faecalis. The resistance rates of Enterococcus faecium to vancomycin and teicoplanin were both 0.5%(2/369),and no vancomycin-resistant Enterococcus faecium was detected. The detection rate of MRSA in southern China was significantly lower than that in other regions( χ2=14.578, P=0.002),while the detection rate of MRCNS in northern China was significantly higher than that in other regions( χ2=15.195, P=0.002). The detection rates of MRSA and MRCNS in provincial hospitals were higher than those in municipal hospitals( χ2=13.519 and 12.136, P<0.001). The detection rates of MRSA and MRCNS in economically more advanced regions(per capita GDP≥92 059 Yuan in 2022)were higher than those in economically less advanced regions(per capita GDP<92 059 Yuan)( χ2=9.969 and 7.606, P=0.002和0.006). Conclusions:Among the Gram-positive pathogens causing bloodstream infections in China, Staphylococci is the most common while the MRSA incidence decreases continuously with time;the detection rate of Enterococcus faecium exceeds that of Enterococcus faecalis. The overall prevalence of vancomycin-resistant Enterococci is still at a low level. The composition ratio of Gram-positive pathogens and resistant profiles varies slightly across regions of China,with the prevalence of MRSA and MRCNS being more pronounced in provincial hospitals and areas with a per capita GDP≥92 059 yuan.
8.BRICS report of 2021: The distribution and antimicrobial resistance profile of clinical bacterial isolates from blood stream infections in China
Yunbo CHEN ; Jinru JI ; Zhiying LIU ; Chaoqun YING ; Qing YANG ; Haishen KONG ; Jiliang WANG ; Hui DING ; Haifeng MAO ; Yizheng ZHOU ; Yan JIN ; Yongyun LIU ; Yan GENG ; Yuanyuan DAI ; Hong LU ; Peng ZHANG ; Ying HUANG ; Donghong HUANG ; Xinhua QIANG ; Jilu SHEN ; Hongyun XU ; Fenghong CHEN ; Guolin LIAO ; Dan LIU ; Haixin DONG ; Jiangqin SONG ; Lu WANG ; Junmin CAO ; Lixia ZHANG ; Yanhong LI ; Dijing SONG ; Zhuo LI ; Youdong YIN ; Donghua LIU ; Liang GUO ; Qiang LIU ; Baohua ZHANG ; Rong XU ; Yinqiao DONG ; Shuyan HU ; Kunpeng LIANG ; Bo QUAN ; Lin ZHENG ; Ling MENG ; Liang LUAN ; Jinhua LIANG ; Weiping LIU ; Xuefei HU ; Pengpeng TIAN ; Xiaoping YAN ; Aiyun LI ; Jian LI ; Xiusan XIA ; Xiaoyan QI ; Dengyan QIAO ; Yonghong XIAO
Chinese Journal of Clinical Infectious Diseases 2023;16(1):33-47
Objective:To report the results of national surveillance on the distribution and antimicrobial resistance profile of clinical bacterial isolates from bloodstream infections in China in 2021.Methods:The clinical bacterial strains isolated from blood culture from member hospitals of Blood Bacterial Resistant Investigation Collaborative System (BRICS) were collected during January 2021 to December 2021. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical Laboratory Standards Institute (CLSI). WHONET 5.6 was used to analyze data.Results:During the study period, 11 013 bacterial strains were collected from 51 hospitals, of which 2 782 (25.3%) were Gram-positive bacteria and 8 231 (74.7%) were Gram-negative bacteria. The top 10 bacterial species were Escherichia coli (37.6%), Klebsiella pneumoniae (18.9%), Staphylococcus aureus (9.8%), coagulase-negative Staphylococci (6.3%), Pseudomonas aeruginosa (3.6%), Enterococcus faecium (3.6%), Acinetobacter baumannii (2.8%), Enterococcus faecalis (2.7%), Enterobacter cloacae (2.5%) and Klebsiella spp (2.1%). The prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase-negative Staphylococcus aureus were 25.3% and 76.8%, respectively. No glycopeptide- and daptomycin-resistant Staphylococci was detected; more than 95.0% of Staphylococcus aureus were sensitive to ceftobiprole. No vancomycin-resistant Enterococci strains were detected. The rates of extended spectrum B-lactamase (ESBL)-producing isolated in Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were 49.6%, 25.5% and 39.0%, respectively. The prevalence rates of carbapenem-resistance in Escherichia coli and Klebsiella pneumoniae were 2.2% and 15.8%, respectively; 7.9% of carbapenem-resistant Klebsiella pneumoniae was resistant to ceftazidime/avibactam combination. Ceftobiprole demonstrated excellent activity against non-ESBL-producing Escherichia coli and Klebsiella pneumoniae. Aztreonam/avibactam was highly active against carbapenem-resistant Escherichia coli and Klebsiella pneumoniae. The prevalence rate of carbapenem-resistance in Acinetobacter baumannii was 60.0%, while polymyxin and tigecycline showed good activity against Acinetobacter baumannii (5.5% and 4.5%). The prevalence of carbapenem-resistance in Pseudomonas aeruginosa was 18.9%. Conclusions:The BRICS surveillance results in 2021 shows that the main pathogens of blood stream infection in China are gram-negative bacteria, in which Escherichia coli is the most common. The MRSA incidence shows a further decreasing trend in China and the overall prevalence of vancomycin-resistant Enterococci is low. The prevalence of Carbapenem-resistant Klebsiella pneumoniae is still on a high level, but the trend is downwards.
9.Association of sleep duration and risk of frailty among the elderly over 80 years old in China: a prospective cohort study.
Wen Fang ZHONG ; Fen LIANG ; Xiao Meng WANG ; Pei Liang CHEN ; Wei Qi SONG ; Ying NAN ; Jia Xuan XIANG ; Zhi Hao LI ; Yue Bin LYU ; Xiao Ming SHI ; Chen MAO
Chinese Journal of Preventive Medicine 2023;57(5):607-613
Objective: To explore the association between sleep duration and the risk of frailty among the elderly over 80 years old in China. Methods: Using the data from five surveys of the China Elderly Health Influencing Factors Follow-up Survey (CLHLS) (2005, 2008-2009, 2011-2012, 2014, and 2017-2018), 7 024 elderly people aged 80 years and above were selected as the study subjects. Questionnaires and physical examinations were used to collect information on sleep time, general demographic characteristics, functional status, physical signs, and illness. The frailty state was evaluated based on a frailty index that included 39 variables. The Cox proportional risk regression model was used to analyze the correlation between sleep time and the risk of frailty occurrence. A restricted cubic spline function was used to analyze the dose-response relationship between sleep time and the risk of frailty occurrence. The likelihood ratio test was used to analyze the interaction between age, gender, sleep quality, cognitive impairment, and sleep duration. Results: The age M (Q1, Q3) of 7 024 subjects was 87 (82, 92) years old, with a total of 3 435 (48.9%) patients experiencing frailty. The results of restricted cubic spline function analysis showed that there was an approximate U-shaped relationship between sleep time and the risk of frailty. When sleep time was 6.5-8.5 hours, the elderly had the lowest risk of frailty; Multivariate Cox proportional risk regression model analysis showed that compared to 6.5-8.5 hours of sleep, long sleep duration (>8.5 hours) increased the risk of frailty by 13% (HR: 1.13; 95%CI: 1.04-1.22). Conclusion: There is a nonlinear association between sleep time and the risk of frailty in the elderly.
Aged
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Humans
;
Aged, 80 and over
;
Frailty/epidemiology*
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Sleep Duration
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Prospective Studies
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Sleep/physiology*
;
China/epidemiology*
10.Prediction of superantigen active sites and clonal expression of staphylococcal enterotoxin-like W.
Yu Hua YANG ; Xin KU ; Ya Nan GONG ; Fan Liang MENG ; Dong bo BU ; Ya Hui GUO ; Xiao Yue WEI ; Li Jin LONG ; Jia Ming FAN ; Mao Jun ZHANG ; Jian Zhong ZHANG ; Xiao Mei YAN
Chinese Journal of Epidemiology 2023;44(4):629-635
Objective: The docking and superantigen activity sites of staphylococcal enterotoxin-like W (SElW) and T cell receptor (TCR) were predicted, and its SElW was cloned, expressed and purified. Methods: AlphaFold was used to predict the 3D structure of SElW protein monomers, and the protein models were evaluated with the help of the SAVES online server from ERRAT, Ramachandran plot, and Verify_3D. The ZDOCK server simulates the docking conformation of SElW and TCR, and the amino acid sequences of SElW and other serotype enterotoxins were aligned. The primers were designed to amplify selw, and the fragment was recombined into the pMD18-T vector and sequenced. Then recombinant plasmid pMD18-T was digested with BamHⅠand Hind Ⅲ. The target fragment was recombined into the expression plasmid pET-28a(+). After identification of the recombinant plasmid, the protein expression was induced by isopropyl-beta-D- thiogalactopyranoside. The SElW expressed in the supernatant was purified by affinity chromatography and quantified by the BCA method. Results: The predicted three-dimensional structure showed that the SElW protein was composed of two domains, the amino-terminal and the carboxy-terminal. The amino-terminal domain was composed of 3 α-helices and 6 β-sheets, and the carboxy-terminal domain included 2 α-helices and 7 antiparallel β-sheets composition. The overall quality factor score of the SElW protein model was 98.08, with 93.24% of the amino acids having a Verify_3D score ≥0.2 and no amino acids located in disallowed regions. The docking conformation with the highest score (1 521.328) was selected as the analysis object, and the 19 hydrogen bonds between the corresponding amino acid residues of SElW and TCR were analyzed by PyMOL. Combined with sequence alignment and the published data, this study predicted and found five important superantigen active sites, namely Y18, N19, W55, C88, and C98. The highly purified soluble recombinant protein SElW was obtained with cloning, expression, and protein purification. Conclusions: The study found five superantigen active sites in SElW protein that need special attention and successfully constructed and expressed the SElW protein, which laid the foundation for further exploration of the immune recognition mechanism of SElW.
Humans
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Enterotoxins/genetics*
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Superantigens/genetics*
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Catalytic Domain
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Selenoprotein W/metabolism*
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Receptors, Antigen, T-Cell

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