[摘 要] 目的：开发新型溶瘤呼肠孤病毒（Reo）递送系统，以克服中和抗体对Reo的中和作用并提升其肿瘤靶向性。方法：通过切向流过滤联合超高速离心法制备自然杀伤细胞外泌体（NKexo），叶酸（FA）修饰后采用挤压法包载Reo，构建FA-NKexo-Reo递送系统；通过透射电镜（TEM）、纳米粒径分析、蛋白质印迹（WB）法、核磁共振氢谱及流式细胞术等技术表征其理化性质；采用CCK-8、流式细胞术、Transwell实验及激光共聚焦显微镜评估FA-NKexo-Reo递送系统体外细胞毒性及细胞摄取能力；通过人卵巢癌裸鼠皮下移植瘤模型评价FA-NKexo-Reo的肿瘤靶向性、疗效及安全性。结果：FA-NKexo-Reo粒径为（94.0 ± 28.5）nm，Zeta电位为（-21.26 ± 1.57）mV，包封率达（49.7 ± 15.6）%；在中和抗体的存在下，FA-NKexo-Reo对卵巢癌细胞SKOV3和A2780仍可表现出显著的细胞毒性（P < 0.01）；荷瘤鼠活体成像显示FA-NKexo-Reo肿瘤靶向性显著优于NKexo组，肿瘤抑制率提升60%（P < 0.001）。结论：成功制备FA-NKexo-Reo递送系统，在中和抗体的存在下，FA-NKexo-Reo可保护并靶向递送Reo到高表达叶酸受体的卵巢癌细胞，从而增强Reo的抗肿瘤作用。

Objective: To analyze the school tuberculosis (TB) outbreaks and preventive treatment in Hefei from 2022 to 2024, so as to provide reference for TB prevention and control in schools. Methods: Data were collected on all school based TB outbreaks occurring during 2022-2024 in Hefei, defined as ≥2 epidemiologically linked TB cases within the same school during a single semester. Statistical analyses were performed using the Chi square test. Results: Close contacts exhibited significantly higher TB incidence (2.88%) and latent mycobacterium tuberculosis infection (LTBI) rates (13.80%) in the school TB outbreaks, compared to non close contacts (0.12% and 2.63%, respectively). Among close contacts, secondary school students showed lower TB incidence (0.48%) and LTBI prevalence (3.42%) than both primary school or younger children (0.68%, 6.95%) and college students ( 0.78% , 6.50%), with statistically significant differences ( χ 2=360.91, 6.37; 791.71, 102.03, all P <0.05). The proportion of LTBI individuals recommended for preventive therapy was higher in primary school or younger groups (98.59%) than in secondary (95.25%) or college students (86.34%) ( χ 2=25.86, P <0.01). However, among those recommended, close contacts had higher uptake (85.82%) and completion rates (87.25%) of preventive therapy than non close contacts (69.63% and 70.57%); similarly, secondary school students demonstrated higher uptake (91.21%) and completion rates (86.45%) compared to primary school or younger (88.57%, 83.87%) and college students (57.28%, 64.08%) ( χ 2=30.52, 26.72; 125.17, 38.84, all P <0.01). Subsequent TB incidence among LTBI close contacts (13.30%) and among those who did not complete preventive therapy (22.73%) were significantly higher than among non close contacts (2.80%, 2.41%), respectively ( χ 2=32.19, 13.87, both P <0.05). Conclusions In school TB outbreaks, close contacts face higher LTBI prevalence and subsequent TB risk than non close contacts. College students show notably low adherence to preventive therapy. It is necessary to take targeted measures to improve the compliance of preventive measures among students.

BackgroundSchizophrenia， as a common chronic mental disorder， although second-generation antipsychotic drugs have shown significant efficacy in alleviating positive symptoms， the widespread cognitive dysfunction among patients remains a challenge in clinical treatment. Traditional Chinese medicine has unique advantages in the treatment of mental disorders. However， the current clinical research on the combination of Wendan Decoction and antipsychotic drugs for schizophrenia varies in quality， and there is a lack of systematic reviews evaluating its effects on cognitive improvement and safety. ObjectiveTo systematically evaluate the effects of modified Wendan Decoction combined with antipsychotic drugs on schizophrenia symptoms and cognitive improvement， providing evidence-based support for the clinical application of Wendan Decoction. MethodsLiterature searches were conducted in China National Knowledge Infrastructure （CNKI）， Wanfang Data， VIP Information， China Biomedical Literature Service System， China Clinical Trial Registry， PubMed， Web of Science， the Cochrane Library， and Embase to collect randomized controlled trials （RCTs） of modified Wendan Decoction combined with antipsychotic drugs for the treatment of schizophrenia. The search period was from the establishment of the databases to March 19， 2026. The quality of the included literature was evaluated using the Cochrane 6.3. Meta-analysis was performed using RevMan 5.3 software. ResultsA total of 11 studies were included， involving 1 130 patients with schizophrenia. Among them， 566 cases were in the study group （receiving modified Wendan Decoction combined with antipsychotic drugs）， and 564 cases were in the control group （receiving antipsychotic drugs only）. Meta-analysis showed that the effective rate of improvement in psychotic symptoms in the study group was higher than that in the control group （RR=1.21，95% CI： 1.15–1.27， P<0.01）. In terms of psychotic symptoms， the Positive and Negative Symptom Scale （PANSS） positive symptom score （MD=-3.69， 95% CI： -5.87–-1.51， P<0.01） and PANSS total score （MD=-9.20， 95% CI： -11.80–-6.59， P<0.01） of the study group were lower than those of the control group. In cognitive function assessments， the Mini-Mental State Examination （MMSE） score （MD=2.51， 95% CI： 1.33–3.68， P<0.01） and the Loewenstein Occupational Therapy Cognitive Assessment （LOTCA） score （MD=11.85， 95% CI： 2.55–21.15， P=0.010） of the study group were higher than those of the control group， and the Wisconsin Card Sorting Test （WCST） score was lower than that of the control group （MD=-9.34， 95% CI： -12.57–-6.11， P<0.01）. The levels of brain-derived neurotrophic factor （BDNF） （SMD=1.34， 95% CI： 0.63–2.05， P<0.01） and nerve growth factor （NGF） （MD=6.94， 95% CI： 4.00–9.89， P<0.01） of the study group were higher than those of the control group. In terms of safety， there was no statistically significant difference in the incidence of adverse reactions between the two groups （RR=0.60， 95% CI： 0.31–1.18， P=0.14）. ConclusionThe modified Wendan Decoction combined with antipsychotic drugs may be more effective than antipsychotic drugs alone in improving positive symptoms and cognitive function in patients with schizophrenia， and it also exerts a favorable neurotrophic regulatory effect. ［Funded by Postgraduate Education Reform and Quality Improvement Project of Henan Province （number， YJS2023AL060）； Key Scientific Research Projects of Higher Education Institutions in Henan Province （number， 24B320018， 25B310004）］

Objective To explore the construction of α-1,3-galactosyltransferase (GGTA1) gene-knockout (GTKO) Diannan miniature pigs and the kidney xenotransplantation from pigs to rhesus macaques, and to assess the effectiveness of GTKO pigs. Methods The GTKO Diannan miniature pigs were constructed using the CRISPR/Cas9 gene-editing system and somatic cell cloning technology. The phenotype of GTKO pigs was verified through polymerase chain reaction, Sanger sequencing and immunofluorescence staining. Flow cytometry was used to detect antigen-antibody (IgM) binding and complement-dependent cytotoxicity. Kidney xenotransplantation was performed from GTKO pigs to rhesus macaques. The humoral immunity, cellular immunity, coagulation and physiological indicators of the recipient monkeys were monitored. The function and pathological changes of the transplanted kidneys were analyzed using ultrasonography, hematoxylin-eosin staining, immunohistochemical staining and immunofluorescence staining. Results Single-guide RNA (sgRNA) targeting exon 4 of the GGTA1 gene in Diannan miniature pigs was designed. The pGL3-GGTA1-sgRNA1-GFP vector was transfected into fetal fibroblasts of Diannan miniature pigs. After puromycin selection, two cell clones, C59# and C89#, were identified as GGTA1 gene-knockout clones. These clones were expanded to form cell lines, which were used as donor cells for somatic cell nuclear transfer. The reconstructed embryos were transferred into the oviducts of trihybrid surrogate sows, resulting in 13 fetal pigs. Among them, fetuses F04 and F11 exhibited biallelic mutations in the GGTA1 gene, and F04 had a normal karyotype. Using this GTKO fetal pig for recloning and transferring the reconstructed embryos into the oviducts of trihybrid surrogate sows, seven surviving piglets were obtained, all of which did not express α-Gal epitope. The binding of IgM from the serum of rhesus monkey 20# to GTKO pig PBMC was reduced, and the survival rate of GTKO pig PBMC in the complement-dependent cytotoxicity assay was higher than that of wild-type pig. GTKO pig kidneys were harvested and perfused until completely white. After the left kidney of the recipient monkey was removed, the pig kidney was heterotopically transplanted. Following vascular anastomosis and blood flow restoration, the pig kidney rapidly turned pink without hyperacute rejection (HAR). Urine appeared in the ureter 6 minutes later, indicating successful kidney transplantation. The right kidney of the recipient was then removed. Seven days after transplantation, the transplanted kidney had good blood flow, the recipient monkey's serum creatinine level was stable, and serum potassium and cystatin C levels were effectively controlled, although they increased 10 days after transplantation. Seven days after transplantation, the levels of white blood cells, lymphocytes, monocytes and eosinophils in the recipient monkey increased, while platelet count and fibrinogen levels decreased. The activated partial thromboplastin time, thrombin time and prothrombin time remained relatively stable but later showed an upward trend. The recipient monkey survived for 10 days. At autopsy, the transplanted kidney was found to be congested, swollen and necrotic, with a small amount of IgG deposition in the renal tissue, and a large amount of IgM, complement C3c and C4d deposition, as well as CD68⁺ macrophage infiltration. Conclusions The kidneys of GTKO Diannan miniature pigs may maintain normal renal function for a certain period in rhesus macaques and effectively overcome HAR, confirming the effectiveness of GTKO pigs for xenotransplantation.

Objective: To investigate the association between screen time (ST) during leisure time and anxiety-depression symptoms among middle school students, so as to provide a basis for formulating relevant intervention measures. Methods: From November to December 2023, a stratified cluster random sampling method was used to select 2 542 students from junior and senior high school in Taiyuan City. A self designed questionnaire, the Generalized Anxiety Disorder Scale (GAD-7), and the Patient Health Questionnaire (PHQ-9) were used to investigate ST and anxiety/depression symptoms among middle school students. The Logistic regression model was used to explore the association of ST with symptoms of anxiety and depression, as well as with anxiety and depression comorbiditles (CAD). Results: The detection rates of anxiety symptoms, depression symptoms, and CAD were 13.69%, 15.77%, and 10.11%, respectively. The median ST was 2.00 h/d [interquartile range ( IQR =2.38) for weekly averages], with 0.33 h/d ( IQR =1.67) on work days and 5.00 h/d ( IQR=5.50) on rest days. Logistic regression analysis indicated that the total ST of mobile phones during rest days ( OR =1.07, 1.10, 1.11) and the averages ST of mobile phones over a week ( OR = 1.20 , 1.22, 1.29), as well as the total ST of all screen types during rest days ( OR =1.04, 1.04, 1.05) and the averages ST of all screen types over a week ( OR =1.08, 1.09, 1.21) were positively correlated with anxiety symptoms, depression symptoms, and CAD (all P <0.01). Conclusions Among middle school students in Taiyuan City, screen time is positively correlated with symptoms of anxiety or depression and the comorbidity of anxiety and depression, especially smartphone screen time and weekend screen use. Therefore, measures should be implemented to reduce unnecessary screen time among middle school students, especially the use of mobile phones, in order to mitigate the occurrence of anxiety and depression.

Objective To develop GTKO (α-1,3-galactosyltransferase gene-knockout, GTKO)/hCD55 (human CD55) gene-edited xenotransplant donor pigs and verify their function. Methods In this study, CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated nuclease 9), PiggyBac transposon technology and somatic cell nuclear transfer technology were used to construct GTKO/hCD55 gene-edited Diannan miniature pigs. The phenotype and function of GTKO/hCD55 pigs were analyzed by Sanger sequencing, real-time fluorescence quantitative PCR, flow cytometry, immunofluorescence, bisulfite sequencing, antigen-antibody binding assays, and complement-dependent cytotoxicity assays. Results After transfection of PX458 and PiggyBac gene editing vectors into wild-type fetal pig fibroblasts, 48 single-cell colonies were obtained through puromycin drug screening. Two single-cell colonies were selected for somatic cell nuclear transfer, resulting in two fetal pigs at 33 days of gestation. The GGTA1(α-1,3-galactosyltransferase) genotypes of fetal pig F01 were -17 bp and wild type (WT), while the GGTA1 genotypes of fetal pig F02 were -26 bp/+2 bp and -3 bp. The hCD55 mRNA expression levels of both fetal pigs were significantly higher than those of WT pigs (P＜0.01). The fetal pig F02 was selected as the donor cell source for recloning, 11 surviving piglets were obtained, all identified as GTKO/hCD55 gene-edited pigs. These pigs showed absence of α-Gal antigen expression, but weak or no expression of hCD55 was observed. Methylation analysis of the hCD55 gene's CpG island showed hypermethylation in kidney tissue lacking hCD55 expression, whereas it was not methylated or partially methylated in kidney tissue expressing hCD55. Moreover, codon optimization of the CpG island of the hCD55 gene to reduce CG content could achieve stable expression of the hCD55 gene. In addition, antigen-antibody binding experiment showed that the amount of human IgM binding to GTKO/hCD55 gene-edited pig fibroblasts was significantly lower than that of WT pigs (P＜0.01). Complement-dependent cytotoxicity experiment showed that the survival rate of fibroblasts in GTKO/hCD55 pigs was significantly higher than that in WT pigs (P＜0.01). Conclusion This study demonstrates the successful generation of GTKO/hCD55 gene-edited xenotransplant donor pigs. Methylation-induced gene silencing of the hCD55 gene can be effectively avoided by reducing the CG content of the CpG island through codon optimization. This study provides a reference for the development of xenotransplant donor pigs and guides subsequent research on xenotransplantation.

OBJECTIVE: Based on the PTEN-induced hypothetical kinase 1 (PINK1)/Parkin pathway, the effect of acupuncture pretreatment on the expression of mitochondrial autophagy-related proteins in gastrocnemius muscle tissue of rats with exercise-induced muscle damage (EIMD) was observed, and the underlying mechanism of acupuncture pretreatment for the prevention and treatment of EIMD was explored. METHODS: Of 88 SD male rats, aged 6 weeks, 8 rats were randomly selected as a blank group, and the remaining 80 rats were randomized into a model group and an acupuncture pretreatment group, with 40 rats in each group. Either the model group or the acupuncture pretreatment group was subdivided randomly into 5 subgroups with 8 rats in each one according to the time points of sample collection, 0 h, 12 h, 24 h, 48 h and 72 h after modeling. An intermittent downhill running centrifugal exercise was carried out on an animal experimental treadmill to establish the EIMD model in the model group and the acupuncture pretreatment group. The rats in the acupuncture pretreatment group received acupuncture at "Guanyuan" (CV6) and bilateral "Zusanli" (ST36), once a day for 20 min each time, for 7 consecutive days before EIMD model preparation. Transmission electron microscopy was used to observe the ultrastructure of gastrocnemius muscle tissue in each group. The contents of malondialdehyde (MDA), superoxide dismutase (SOD) and catalase (CAT) in serum were detected by ELISA. Western blot was used to detect the protein expression of PINK1, Parkin, sequestosome 1 (p62) and microtubule-associated protein light chain 3B (LC3B) in rat gastrocnemius muscle tissue. Real-time PCR was adopted to detect the mRNA expression of PINK1, Parkin, p62 and LC3B in rat gastrocnemius muscle tissue. RESULTS: Compared with the blank group, the mitochondria of gastrocnemius muscles showed obvious swelling in the 0 h, 12 h, 24 h, and 48 h model subgroups , autophagosomes were formed in the 12 h and 24 h model subgroups, and the mitochondrial morphology returned to normal gradually in the 72 h model subgroup. The serum MDA contents of rats in 5 model subgroups increased (P<0.01, P<0.05). The contents of SOD and CAT in the subgroups of 0 h, 12 h, 24 h and 48 h decreased (P<0.05, P<0.01). The protein and mRNA expression levels of PINK1, Parkin and LC3B in gastrocnemius muscle tissue of rats in 0 h, 12 h and 24 h subgroups were elevated (P<0.01); and the protein and mRNA expression levels of p62 in the 0 h, 12 h, 24 h and 48 h subgroups were reduced (P<0.01, P<0.05). Compared with the model subgroup at the same time point, the myofibril damage and the degree of mitochondrial swelling were mild in each acupuncture pretreatment subgroup, and the numbers of autophagosomes were fewer. The contents of MDA in the acupuncture pretreatment subgroups decreased at 0 h, 12 h, 24 h, and 48 h (P<0.05, P<0.01). The contents of SOD and CAT in the 12 h acupuncture pretreatment subgroup increased (P<0.05, P<0.01). The protein and mRNA expression levels of PINK1 and Parkin in the 0 h, 12 h, and 24 h acupuncture pretreatment subgroups decreased (P<0.01, P<0.05). The protein and mRNA expression levels of LC3B in the 12 h acupuncture pretreatment subgroup decreased (P<0.01), and that of p62 in the 0 h and 24 h acupuncture pretreatment subgroups increased (P<0.01, P<0.05). CONCLUSION The intermittent downhill running centrifugal exercise induces the excessive mitochondrial autophagy. Acupuncture pretreatment may attenuate EIMD, and the underlying mechanism is related to the regulation of PINK1/Parkin signaling pathway expression, reducing oxidative stress damage in skeletal muscle cells, and inhibiting mitochondrial autophagy overactivation.
Animals ; Ubiquitin-Protein Ligases/genetics* ; Male ; Rats ; Acupuncture Therapy ; Protein Kinases/genetics* ; Rats, Sprague-Dawley ; Mitophagy ; Humans ; Muscle, Skeletal/metabolism* ; Physical Conditioning, Animal ; Muscular Diseases/physiopathology* ; Signal Transduction

OBJECTIVE To explore the effect of Zi Zhu Ointment combined with herbal fumigation on wound heal-ing,oxidative stress and microribonucleic acid(miR)-200b of the patients with diabetic foot infection.METHODS A total of 102 patients with diabetic foot infection who were treated in Heping Hospital Affiliated to Changzhi Medical College from Sep.2020 to Sep.2023 were enrolled in the study and were divided into the control group with 48 cases and the study group with 54 cases according to the treatment program.The control group was trea-ted with conventional therapy and herbal fumigation,the study group was given additional Zi Zhu Ointment on ba-sis of the treatment of the control group,and both groups were persistently treated for 1 month.The clinical cura-tive effect,wound healing status,hemodynamics indexes of dorsal foot,pain score,oxidative stress indexes and miR-200b expression levels were observed and compared between the two groups of patients.RESULTS The effec-tive rate of clinical treatment of the study group was higher than that of the control group after the treatment(Z=2.138,P=0.033).The wound area of the study group was(0.42±0.05)cm2 after the treatment,smaller than that of the control group;the cover area of neoplastic granulation tissue of the study group was(16.87±3.21)cm2,larger than that of the control group;the coverage fraction of the neoplastic granulation tissue of the study group was(55.23±6.17)％,greater than that of the control group;there were significant differences between the two groups(P＜0.05).The blood vessel diameter of dorsal foot of the study group was greater than that of the control group after the treatment,the blood flow velocity of the study group was greater than that of the control group,and the visual analogue scale(VAS)score of the study group was lower than that of the control group(P＜0.05).There were no significant differences in the expression levels of advanced oxidative protein product(AOPP),superoxide dismutase(SOD),malondialdehyde(MDA)and miR-200b between the two groups of pa-tients before the treatment;the expression levels of AOPP,MDA and miR-200b of the study group were lower than those of the control group after the treatment,while the SOD level of the study group was higher than that of the control group(P＜0.05).CONCLUSIONS Zi Zhu Ointment combined with herbal fumigation can remarkably improve the clinical curative effect on the patients with diabetic foot infection,promote the wound healing,im-prove the arterial hemodynamics of dorsal foot,and relieve the pain.The mechanism may be associated with the improvement of oxidative stress response and downregulated expression level of miR-200b.

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.