Observational studies are important approaches for obtaining real-world evidence.However,due to the lack of randomized allocation,differences in baseline characteristics between groups often introduce confounding bias,which may distort the results.Traditional stratified analyses and multivariable regression models have limited ability to control confounding when multiple covariates are involved.Propensity score matching estimates the probability of receiving an intervention based on observed covariates,then matches individuals with similar propensity scores between treatment and control groups,thereby balancing covariate distributions and reducing confounding.In recent years,propensity score matching has been widely applied in various fields,including chronic disease management and drug effectiveness evaluation,public health policy and health service assessment,vaccine effectiveness studies focusing on population disparities,and evaluations of telemedicine interventions.This review summarizes common matching methods and application scenarios of propensity score matching in observational studies.

During sudden outbreaks of major infectious diseases,traditional vaccine clinical trials often fail to deliver timely and meaningful outcomes.To address this,innovative trial designs are essential to accelerate or restructure the traditional three-phase clinical trial process while maintaining adherence to scientific principles of drug candidate safety and efficacy.This paper presents various innovative vaccine clinical trial designs and concepts,along with critical considerations for their application,to serve as a methodological reference for related research.Adaptive designs provide flexibility by dynamically adjusting trial parameters—such as dose selection,population stratification,and sample size reestimation—based on interim analysis results.Bayesian designs incorporate historical data and prior information,reducing sample size requirements.Master protocol designs enable the evaluation of multiple treatments or target populations within a unified framework,significantly improving efficiency.Additionally,real-world data(RWD),including electronic health records vaccination records and insurance claims,supports the creation of virtual control groups,addressing ethical concerns while enhancing trial feasibility.A hybrid design combining randomized controlled trials(RCTs)with RWD is also proposed to leverage the strengths of both methodologies.These innovative designs optimize the research process,accelerating vaccine development and regulatory approval.By integrating these approaches,robust evidence-based insights can be generated,advancing precision medicine goals and strengthening public health responses to emerging infectious diseases.

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.

During sudden outbreaks of major infectious diseases,traditional vaccine clinical trials often fail to deliver timely and meaningful outcomes.To address this,innovative trial designs are essential to accelerate or restructure the traditional three-phase clinical trial process while maintaining adherence to scientific principles of drug candidate safety and efficacy.This paper presents various innovative vaccine clinical trial designs and concepts,along with critical considerations for their application,to serve as a methodological reference for related research.Adaptive designs provide flexibility by dynamically adjusting trial parameters—such as dose selection,population stratification,and sample size reestimation—based on interim analysis results.Bayesian designs incorporate historical data and prior information,reducing sample size requirements.Master protocol designs enable the evaluation of multiple treatments or target populations within a unified framework,significantly improving efficiency.Additionally,real-world data(RWD),including electronic health records vaccination records and insurance claims,supports the creation of virtual control groups,addressing ethical concerns while enhancing trial feasibility.A hybrid design combining randomized controlled trials(RCTs)with RWD is also proposed to leverage the strengths of both methodologies.These innovative designs optimize the research process,accelerating vaccine development and regulatory approval.By integrating these approaches,robust evidence-based insights can be generated,advancing precision medicine goals and strengthening public health responses to emerging infectious diseases.

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.

With the deepening of molecular biology and cell biology research,the regulatory mechanism of autophagy has been gradually revealed,providing new ideas for the treatment of numerous diseases.Autophagy may be closely related to pathological changes such as apoptosis resistance of fibroblast-like synoviocytes,disturbances in bone metabolic homeostasis,and antigen presentation,the regulation of autophagy homeostasis may be an important approach for the treatment of rheumatoid arthritis(RA).In this paper,we provide a review on the pathological mechanism of autophagy in RA,with a view to providing a theoretical basis for later studies.

Aim To investigate the differential characteristics of endogenous metabolites between two breast cancer cells with dif-ferent metastatic abilities(MCF-7 and MDA-MB-231)based on metabolomics,and to screen metabolic markers closely related to the metastasis potential of breast cancer cells.Methods Gas chromatography and time-of-flight mass spectrometry(GC-TOFMS)combined with multivariate statistical method were used to analyze the metabolic profile characteristics of these two breast cancer cells,and to find the different metabolites and re-lated metabolic pathways between the two groups.Results A total of 118 metabolites of cells were identified,and a discrimi-nant model for predicting metastasis potential of breast cancer cells was established.Fifty-six metabolites were found to be sig-nificantly different between MCF-7 cells and MDA-MB-231 cells.The main related metabolic pathways included alanine,as-partate and glutamate metabolism,purine metabolism,glycine,serine and threonine metabolism.There were four characteristic metabolites(adenosine,guanosine,glyceric acid,creatine)that were finally selected as biomarkers used for identification of the metastasis potential of breast cancer cells.Conclusions There is a potential association between metabolites and the metastasis ability of breast cancer cells,which can be used to identify the metastatic potential of tumor cells.This finding may provide po-tential targets for understanding the mechanisms of breast cancer metastasis and developing new drugs.

Aim To investigate the differential characteristics of endogenous metabolites between two breast cancer cells with dif-ferent metastatic abilities(MCF-7 and MDA-MB-231)based on metabolomics,and to screen metabolic markers closely related to the metastasis potential of breast cancer cells.Methods Gas chromatography and time-of-flight mass spectrometry(GC-TOFMS)combined with multivariate statistical method were used to analyze the metabolic profile characteristics of these two breast cancer cells,and to find the different metabolites and re-lated metabolic pathways between the two groups.Results A total of 118 metabolites of cells were identified,and a discrimi-nant model for predicting metastasis potential of breast cancer cells was established.Fifty-six metabolites were found to be sig-nificantly different between MCF-7 cells and MDA-MB-231 cells.The main related metabolic pathways included alanine,as-partate and glutamate metabolism,purine metabolism,glycine,serine and threonine metabolism.There were four characteristic metabolites(adenosine,guanosine,glyceric acid,creatine)that were finally selected as biomarkers used for identification of the metastasis potential of breast cancer cells.Conclusions There is a potential association between metabolites and the metastasis ability of breast cancer cells,which can be used to identify the metastatic potential of tumor cells.This finding may provide po-tential targets for understanding the mechanisms of breast cancer metastasis and developing new drugs.