Objective To understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective:To carry out carrier screening among people of childbearing age, detect the pathogenic genes of monogenic genetic diseases and analyze the carrier status of pathogenic variants, so as to provide fertility guidance and intervention measures for high-risk families.Methods:From August 2022 to August 2023, 1 533 families of childbearing age who met the criteria were recruited in the Chinese PLA General Hospital, including a total of 3 044 subjects. According to the standard enrollment procedure, 223 genes (197 autosomal recessive genes and 26 X-linked genes) of the subjects were tested. According to the screening results, genetic counseling and fertility guidance were provided to the subjects. Invasive prenatal diagnosis was performed for high-risk couples (both couples being carriers of the same autosomal recessive disease gene or the woman was a carrier of X-linked disease gene), and their pregnancy pattern, outcome and offspring phenotype were followed up.Results:(1) A total of 3 044 cases from 1 511 couples and women of childbearing age from 22 families were included for carrier screening. Totally 1 503 families chose simultaneous screening and 30 families chose sequential screening out of the 1 533 families. Among the 3 044 subjects, 1 603 individuals carried at least one pathogenic or likely pathogenic variant, and the overall carrier rate was 52.66% (1 603/3 044). A total of 2 292 pathogenic or likely pathogenic variants were detected, and 0.75 variants (2 292/3 044) were detected per capita. (2) The three genes with the highest carrier rates were GJB2 (8.67%, 264/3 044), CYP21A2 (3.19%, 97/3 044) and PAH (3.09%, 94/3 044). There were 32 genes with a carrier rate ≥1/200, 17 genes with a carrier rate ≥1/100, and 7 genes with a carrier rate ≥1/50. (3) Thirty-eight high-risk families were identified. After excluding G6PD gene mutation, there were 33 high-risk families, of which 25 couples were carriers of the same autosomal recessive gene, 9 women were carriers of X-linked gene, and 1 family was double high-risk couple with both autosomal recessive and X-linked gene. After further excluding the GJB2 c.109G>A mutation, 21 high-risk families were identified. Preimplantation genetic testing for monogenic disease was performed in 12 families after genetic counseling. Prenatal diagnosis was completed in 4 out of 5 high-risk families who conceived naturally. Two fetuses carried the parental variants and terminated the pregnancy, one fetus did not carry the parental variants but was induced due to trisomy 21 syndrome, and one fetus was a carrier of congenital disorders of glycosylation type 1a.Conclusions:Carrier screening effectively identifies high-risk genetic disease families and provides reproductive guidance to prevent the birth of affected children. However, establishing multidisciplinary team is essential for managing complex cases. Implementation should prioritize prenatal institutions with genetic counseling or diagnostic expertise for monogenic disorders or established referral networks.

Objective To investigate the effects and mechanism of Dahuang Lingxian Prescription on bile duct reaction of cholestatic liver fibrosis rats caused by bile duct ligation.Methods A total of 40 SD rats were randomly divided into blank group,model group,ursodeoxycholic acid group and Dahuang Lingxian Prescription group,with 10 rats in each group.Except for the blank group,the remaining groups of rats underwent bile duct ligation surgery to establish a cholestatic liver fibrosis model.After surgery,the ursodeoxycholic acid group was given ursodeoxycholic acid solution by gavage,Dahuang Lingxian Prescription group was given Dahuang Lingxian Prescription solution by gavage,and the blank group and model group were given equal volume of normal saline by gavage,once a day for 3 consecutive weeks.The activities of serum AST,ALT,ALP,GGT and the contents of TBIL,TBA were tetected,the morphology of liver tissue was observed by HE staining,and the liver fibrosis was observed by Masson staining,immunohistochromic staining and Western blot were used to detect the expressions of CK19,CK7,EpCAM and SOX9 proteins.Results Compared with the blank group,the liver surface of the model group rats was rough,with a harder texture and obvious graininess,HE staining showed damage to the liver lobule structure,forming pseudo lobules,a large number of bile duct hyperplasia and inflammatory cell infiltration,and a significant increase in collagen fiber deposition(P<0.01);the activities of serum AST,ALT,ALP,GGT,as well as the contents of TBIL and TBA significantly increased(P<0.01);the positive expressions of CK19,CK7 and EpCAM in liver tissue significantly increased(P<0.01),and the protein expressions of CK19,CK7,EpCAM and SOX9 significantly increased(P<0.01).Compared with the model group,the appearance and texture of the liver of the rats in the ursodeoxycholic acid group and Dahuang Lingxian Prescription group were relatively softer,the lobular structure was less damaged,the inflammatory cells infiltration was less,the collagen fiber deposition was significantly reduced(P<0.01),the activities of serum AST,ALT,ALP,GGT,and the contents of TBIL and TBA were significantly decreased(P<0.01);the expressions of TBA and TBIL were significantly decreased(P<0.01),the positive expressions of CK19,CK7 and EpCAM significantly decreased(P<0.01),and the protein expression of CK19,CK7,EpCAM and SOX9 significantly decreased(P<0.01).Conclusion Dahuang Lingxian Prescription can inhibit the bile duct reaction associated with liver progenitor cells,decrease the expression of CK19,CK7,EpCAM and SOX9,and thus improve the cholestatic liver fibrosis of rats induced by bile duct ligation.

Objective To identify the key factors affecting the risk of medical surges and their coupling relation5 ships,providing strategic support for medical institutions to optimize risk management and emergency governance.Methods 17 influencing factors were determined based on WSR theory,and an expert scoring method was employed to assess the impact strength among the factors.The DEMATEL method was applied to calculate the centrality,cau5 sality,influence,and being influenced degrees of the influencing factors.The ISM method was used to construct a hierarchical structure of the influencing factors related to medical surge risks,thereby revealing the connections and interaction mechanisms among these factors.Results Seven critical influencing factors were identified,including the crisis decision-making capacity and leadership effectiveness of emergency managers,the completeness of the emer5 gency system and dynamic execution capabilities,and the cross-departmental coordination mechanism and com5 mand collaboration efficiency.Deep driving factors and coupling pathways were also revealed.Conclusion The risk of medical surges exhibits multi-factorial coupling cascade effects;attention should be directed towards the construc5 tion of mid-to-deep level mechanisms such as information systems,institutional frameworks,and organizational management,to enhance targeted capabilities and systemic resilience in risk governance.

Objective Exploring the components of complex scenarios of healthcare surges triggered by major epidemics to provide a theorical basis for building resilience in healthcare organizations.Methods A hybrid analysis method is used to summarize macro-meso-micro multi-level and multi-source heterogeneous information,extract the elements of complex scenarios of medical surge and evaluate the rationality.Fault Tree Analysis method is used to clarify the logical relationship between various scenario elements and construct scenario reasoning paths.Results 10 scenario states,11 disaster-bearing,24 emergency management and 23 scenario results are summarized and extracted to form the key elements of complex surge scenarios.Among them,M4 expansion and coordinated scheduling of key positions,B2 conventional drug inventory emergency/insufficient core treatment drugs,B emergency medical material transportation breakage,S3 disease symptom spectrum shift to severe disease,R13 prevention and control awareness laxity,and M5 media information dissemination management are the key driving factors that promote a major turning point in the scenario.The most positive scenario result is the orderly operation of the medical service system,and the most negative scenario result is the paralysis of the medical service system.Conclusion Medical institutions need to improve emergency plans based on the complex evolution scenarios of medical surges and agile governance capabilities targeting key turning points,focus on dynamically expanding and scheduling personnel in key positions,strengthen material rotation and reserve mechanisms,maintain smooth emergency logistics channels,and improve efficient management of media and public opinion,so as to comprehensively improve overall resilience.

Objective To explore the coupling mechanism between medical surge response resources and the spread of secondary risks during public health emergencies,as well as the effectiveness of relevant interventions.Methods Based on complex network theory,a dual-layer network model of medical resources and secondary events was constructed.The interactive feedback between medical resource status and secondary event risk,as well as the effects of network structure,were analyzed through MATLAB simulations,REPAST agent-based modeling,and mean-field analysis.Results Simulation and prediction results show that an increase in first-layer resource-deficient nodes significantly raises the activation rate and transmission speed of secondary events,while the clustering and spread of secondary events in the second layer,in turn,intensify resource depletion,creating a negative feedback loop.Mean-field analysis indicates a nonlinear positive correlation between the adequacy of medical resources and the likelihood of secondary events.Network structure analysis reveals that when the average node degree exceeds 8,resource allocation efficiency improves markedly.Conclusion There exists a dynamic coupling and bidirectional feedback relationship between medical resource status and secondary event risks.Enhancing the flexible allocation and responsiveness of medical resources,improving multi-sectoral collaborative monitoring and coordinated regulation,optimizing network connectivity and coordination mechanisms for resource distribution,and establishing dynamic monitoring and tiered early warning systems are key strategies for strengthening the resilience of healthcare systems and effectively containing the spread of secondary events.

Objective To define the conceptual connotation of network dynamic collaboration capacity in medical surge response and construct its theoretical model.Methods A mixed concept analysis method was employed,integrating multidisciplinary literature and collecting empirical evidence through semi-structured expert interviews to extract the concept of network dynamic collaboration capacity in medical surge response.By integrating complex systems,network science,synergetics,and dynamic capability theory,and combining the interview results,the study used the analogy of flood control in hydraulic engineering to develop a"network-dynamic-collaboration"triangular capacity theoretical model.Results It reveals one antecedents(sudden external shocks have led to an abnormal and continuous surge in medical demand),six core attributes(information interconnection accessibility,dynamic resource adaptability,risk perception responsiveness,multi-party collaborative interactivity,service process adaptability elasticity,and learning iterative evolution),and four consequences(mitigation of crowding risk,protection of service continuity,minimization of crisis spillover,and enhancement of system resilience)for the network dynamic collaboration capacity in medical surge response.The theoretical model elucidates the coupling mechanisms among network structural resilience,dynamic regulation processes,and collaborative co-evolution in resisting medical surge.Conclusion The new concept and theoretical model proposed in this study deepen the understanding of medical surge response system mechanisms and offer a theoretical framework and practical guidance for strengthening the full-chain resilience of health emergency systems.

Objective To empirically analyze multiple pathways for enhancing medical surge response capacity and provide useful references for improving the resilience of health systems.Methods A comprehensive theoretical analysis framework for improving medical surge response capacity was constructed based on the 4S theory and collaborative governance theory.68 interview texts on medical surge response capacity conducted in July 2024 were selected as analysis samples.Using fuzzy-set Qualitative Comparative Analysis(fsQCA),7 conditional variables were selected from four dimensions:management system,information system,materials,and personnel to analyze their impact on medical surge response capacity.Results(1)A single conditional variable does not constitute a necessary condition for improving medical surge response capacity;(2)After the combination of conditions,8 specific configuration paths for capacity improvement were identified.Through systematic and comprehensive refinement,they were summarized into three modes of comprehensive configuration capacity improvement paths,namely:rapid response and collaborative operation mode,information empowerment and precise response mode,and resource conditions and resilience construction mode.Conclusion It is necessary to explore and construct systematic,combined,modularized and path-oriented capacity building strategies,refine the operational implementation paths for improving China's medical surge response capacity,target the linkage and configuration modes of different conditional variables,promote the formulation and implementation of modular construction schemes oriented by key capacity,and make efforts from multiple aspects to enhance the resilience of the health system.

Objective To investigate the predictive value of the combined detection of serum von Willebrand factor(vWF),monocyte chemotactic protein-1(MCP-1),and growth differentiation factor-15(GDF-15)for postpartum hemorrhage in patients with pernicious placenta previa(PPP).Methods One hundred and twelve patients with PPP admitted to our hospital between January 2021 and January 2024 were selected as the study group.They were further divided into a postpartum hemorrhage group and a non-postpartum hemorrhage group and 112 pregnant women with normal placental position during the same period were selected as the control group.ELISA was used to detect serum vWF,MCP-1,and GDF-15 levels.Results Serum vWF,MCP-1,and GDF-15 levels were significantly higher in the study group than in the control group(P＜0.05).Serum vWF,MCP-1,and GDF-15 levels were significantly higher in the postpartum hemorrhage group than in the non-postpartum hemorrhage group(P＜0.05).Logistic regression analysis identified vWF,MCP-1,and GDF-15 levels as factors influencing postpartum hemorrhage for women with PPP(P＜0.05).The combination of serum vWF,MCP-1,and GDF-15 predicted postpartum hemorrhage in women with PPP better than either factor alone(P＜0.05).Conclusion Combined detection of serum vWF,MCP-1,and GDF-15 levels has predictive value for postpartum hemorrhage in women with PPP.