Objective To establish a flow cytometry method for detecting C1s protein on platelet surface and preliminarily explore its potential application value in the auxiliary diagnosis of primary immune thrombocytopenia(ITP).Methods C1s-conjugated 2 μm car-boxylated magnetic beads(C1s beads)were prepared and used as quality control particles.Fluorescein isothiocyanate(FITC)-labeled anti-C1s antibody was employed as the detection antibody to develop a flow cytometric assay for detecting C1s protein expression on platelets.The intra-assay and inter-assay precision,as well as the dilution linearity of the method,were evaluated.Subsequently,the expression levels of C1 s protein on the surface of platelets were compared among the ITP group,the non-ITP thrombocytopenia group,and the healthy control group.Results Light microscopy showed that both unconjugated carboxylated magnetic beads(blank beads)and C1s-conjugated beads were uniformly dispersed without aggregation.Under fluorescence microscopy,C1s beads exhibited strong yellow-green fluorescence,whereas the blank beads showed no fluorescence signal.The established flow cytometry assay exhibited ac-ceptable precision,with intra-assay coefficient of variation(CV)values of 7.02％,7.12％,and 3.91％for low,medium,and high con-centrations of C1s beads,respectively,and inter-assay CV values of 13.49％,6.15％,and 0.78％,respectively.The dilution linearity was satisfactory,coefficient of determination(R2)=0.998 8.Clinical sample testing revealed that the proportion of C1s-positive plate-lets in ITP group(2.56±0.79)％was significantly higher than that in healthy control group(0.23±0.18)％and the non-ITP thrombo-cytopenia control group(0.22±0.10)％,with statistically significant differences(both P＜0.05).Conclusion This study successfully established a stable and reliable flow-cytometry method for quantifying C1s expression on platelet surface and preliminarily demonstrated that C1s expression is significantly elevated on platelets of ITP patients,suggesting that C1s could serve as a potential auxiliary diag-nostic marker for ITP.

Objective:To evaluate the effectiveness of entrustable professional activities (EPAs) in the general practice internship of undergraduate clinical medicine students, identify issues that need improvement in the internship, and enhance medical students' competence.Methods:A total of 75 students in the five-year (English class) clinical medicine program enrolled in 2018 and 2019 who participated in general practice internship in Renji Hospital affiliated to Shanghai Jiao Tong University School of Medicine from October 2021 to October 2023 were selected as study subjects. The design of core EPAs was adopted to assess the correlation among different EPA dimensions and to analyze the qualified rates.Results:The evaluation of EPAs showed that EPA2 (practicing respect, understanding and teamwork) had the highest mean score of 9.33, and EPA10 (chronic disease management and management of key populations) had the lowest mean score of 8.08. A supervision level of 3a and above was used as the criterion for qualification. The supervision levels of the students' EPAs were mostly concentrated at levels 3a and 3b. The highest qualified rate was for EPA2 (practicing respect, understanding and teamwork) at 85.33%, followed by EPA1 (complying with the rules of the profession and demonstrating professionalism) at 80.00% and EPA8 (reviewing information and solving clinical problems) at 72.00%. The lowest qualified rate was for EPA10 (chronic disease management and management of key populations) at 33.33%, followed by EPA4 (analyzing and interpreting test results) at 57.33%.Conclusions:EPAs concretize competency evaluation, which can effectively reflect the "competency-oriented" training objectives encompassing multiple elements such as knowledge, skills, values, and attitudes, while maintaining professional specificity. Undergraduates demonstrated strengths in professionalism and academics, but showed deficiencies in community chronic disease management and management of key populations. These findings suggest the need to strengthen the training in health and social care to better align with the competencies required during standardized residency training.

AIM:To investigate the role and mechanism of cell death-inducing DNA fragmentation factor al-pha(DFFA)-like effector B(Cideb)in promoting palmitic acid(PA)-induced lipid deposition in human hepatoblastoma HepG2 cells.METHODS:The HepG2 cells were divided into control group,model group,negative control silencing(siR-NC)group and Cideb silencing(siR-Cideb)group.The cells were treated with PA to establish a cellular model of lipid deposition.Specific siRNAs were used to silence the expression of Cideb,and the intracellular lipid content was mea-sured.Lipid deposition was observed by oil red O staining.RT-qPCR and Western blot were used to detect the expression levels of Cideb,sterol regulatory element-binding protein 1c(SREBP1c),acetyl-CoA carboxylase 1(ACC1),fatty acid synthase(FAS),stearoyl-CoA desaturase 1(SCD1)and AMP-activated protein kinase α(AMPKα)in the cells.The ef-fects of Cideb overexpression on HepG2 cells were observed by transfection with a Cideb eukaryotic expression plasmid.RESULTS:Compared with control group,the cells in PA model group presented lipid deposition,significantly increased triglyceride(TG)and total cholesterol(TC)content,elevated expression levels of Cideb,SREBP1c,ACC,FAS and SCD1,and decreased expression of AMPKα(P＜0.05).Compared with siR-NC group,the cells in siR-Cideb group pre-sented decreased lipid deposition,reduced intracellular TG and TC content,decreased SREBP1c,ACC,FAS and SCD1 expression levels,and increased AMPKα expression(P＜0.05).The overexpression of Cideb increased the lipid deposi-tion,TG and TC content,and the expression levels of SREBP1c,ACC,FAS and SCD1 in HepG2 cells,but decreased the expression of AMPKα(P＜0.05).CONCLUSION:Reduction of Cideb alleviates PA-induced lipid deposition in HepG2 cells by down-regulating the SREBP1c/ACC/FAS/SCD1 pathway and up-regulating the AMPKα pathway.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

This research aims to construct a stable epithelial cell senescence model for screening and e-valuation of senolytics.We explored the optimal conditions for doxorubicin-induced senescence of non-transformed epithelial cells MCF 10A,including the optimal induction concentration,the optimal inter-vention time,and the optimal senescence duration,and confirmed the feasibility of MCF 10A as an epi-thelial senescence model by multiple ways.The optimal condition for Doxorubicin-induced senescence of MCF 10A cells was treatment with 0.6 μmol/L Doxorubicin for 16 h to achieve the best senescence state on the 8th day.Under the optimal induction conditions,the positive rate of senescence-associated β-gal-actosidase(SA-β-gal)staining in the treated group reached 97％.At the same time,biochemical results of detecting the expression of mRNA,proteins,and immunofluorescence demonstrated that the expression levels of senescence-associated secretory phenotype(SASP),p16,p21 and p53 in the treated group were significantly higher than those in the control cells,and Lamin B1 was significantly decreased(P＜0.001),which were consistent with the specific characteristics of senescence.In summary,an epithelial senescence model was successfully induced in MCF 10A cells by Doxorubicin in this study,which will promote the screening of senolytics for senescent epithelial cells.

Objective To establish a flow cytometry method for detecting C1s protein on platelet surface and preliminarily explore its potential application value in the auxiliary diagnosis of primary immune thrombocytopenia(ITP).Methods C1s-conjugated 2 μm car-boxylated magnetic beads(C1s beads)were prepared and used as quality control particles.Fluorescein isothiocyanate(FITC)-labeled anti-C1s antibody was employed as the detection antibody to develop a flow cytometric assay for detecting C1s protein expression on platelets.The intra-assay and inter-assay precision,as well as the dilution linearity of the method,were evaluated.Subsequently,the expression levels of C1 s protein on the surface of platelets were compared among the ITP group,the non-ITP thrombocytopenia group,and the healthy control group.Results Light microscopy showed that both unconjugated carboxylated magnetic beads(blank beads)and C1s-conjugated beads were uniformly dispersed without aggregation.Under fluorescence microscopy,C1s beads exhibited strong yellow-green fluorescence,whereas the blank beads showed no fluorescence signal.The established flow cytometry assay exhibited ac-ceptable precision,with intra-assay coefficient of variation(CV)values of 7.02％,7.12％,and 3.91％for low,medium,and high con-centrations of C1s beads,respectively,and inter-assay CV values of 13.49％,6.15％,and 0.78％,respectively.The dilution linearity was satisfactory,coefficient of determination(R2)=0.998 8.Clinical sample testing revealed that the proportion of C1s-positive plate-lets in ITP group(2.56±0.79)％was significantly higher than that in healthy control group(0.23±0.18)％and the non-ITP thrombo-cytopenia control group(0.22±0.10)％,with statistically significant differences(both P＜0.05).Conclusion This study successfully established a stable and reliable flow-cytometry method for quantifying C1s expression on platelet surface and preliminarily demonstrated that C1s expression is significantly elevated on platelets of ITP patients,suggesting that C1s could serve as a potential auxiliary diag-nostic marker for ITP.

Objective:To evaluate the effectiveness of entrustable professional activities (EPAs) in the general practice internship of undergraduate clinical medicine students, identify issues that need improvement in the internship, and enhance medical students' competence.Methods:A total of 75 students in the five-year (English class) clinical medicine program enrolled in 2018 and 2019 who participated in general practice internship in Renji Hospital affiliated to Shanghai Jiao Tong University School of Medicine from October 2021 to October 2023 were selected as study subjects. The design of core EPAs was adopted to assess the correlation among different EPA dimensions and to analyze the qualified rates.Results:The evaluation of EPAs showed that EPA2 (practicing respect, understanding and teamwork) had the highest mean score of 9.33, and EPA10 (chronic disease management and management of key populations) had the lowest mean score of 8.08. A supervision level of 3a and above was used as the criterion for qualification. The supervision levels of the students' EPAs were mostly concentrated at levels 3a and 3b. The highest qualified rate was for EPA2 (practicing respect, understanding and teamwork) at 85.33%, followed by EPA1 (complying with the rules of the profession and demonstrating professionalism) at 80.00% and EPA8 (reviewing information and solving clinical problems) at 72.00%. The lowest qualified rate was for EPA10 (chronic disease management and management of key populations) at 33.33%, followed by EPA4 (analyzing and interpreting test results) at 57.33%.Conclusions:EPAs concretize competency evaluation, which can effectively reflect the "competency-oriented" training objectives encompassing multiple elements such as knowledge, skills, values, and attitudes, while maintaining professional specificity. Undergraduates demonstrated strengths in professionalism and academics, but showed deficiencies in community chronic disease management and management of key populations. These findings suggest the need to strengthen the training in health and social care to better align with the competencies required during standardized residency training.