1.Enzyme-directed Immobilization Strategies for Biosensor Applications
Xing-Bao WANG ; Yao-Hong MA ; Yun-Long XUE ; Xiao-Zhen HUANG ; Yue SHAO ; Yi YU ; Bing-Lian WANG ; Qing-Ai LIU ; Li-He ZHANG ; Wei-Li GONG
Progress in Biochemistry and Biophysics 2025;52(2):374-394
Immobilized enzyme-based enzyme electrode biosensors, characterized by high sensitivity and efficiency, strong specificity, and compact size, demonstrate broad application prospects in life science research, disease diagnosis and monitoring, etc. Immobilization of enzyme is a critical step in determining the performance (stability, sensitivity, and reproducibility) of the biosensors. Random immobilization (physical adsorption, covalent cross-linking, etc.) can easily bring about problems, such as decreased enzyme activity and relatively unstable immobilization. Whereas, directional immobilization utilizing amino acid residue mutation, affinity peptide fusion, or nucleotide-specific binding to restrict the orientation of the enzymes provides new possibilities to solve the problems caused by random immobilization. In this paper, the principles, advantages and disadvantages and the application progress of enzyme electrode biosensors of different directional immobilization strategies for enzyme molecular sensing elements by specific amino acids (lysine, histidine, cysteine, unnatural amino acid) with functional groups introduced based on site-specific mutation, affinity peptides (gold binding peptides, carbon binding peptides, carbohydrate binding domains) fused through genetic engineering, and specific binding between nucleotides and target enzymes (proteins) were reviewed, and the application fields, advantages and limitations of various immobilized enzyme interface characterization techniques were discussed, hoping to provide theoretical and technical guidance for the creation of high-performance enzyme sensing elements and the manufacture of enzyme electrode sensors.
2.Altered Cerebral Blood Flow in Type 2 Diabetes Mellitus Without Cognitive Impairment.
Jia-Ying YANG ; Xue-Wei ZHANG ; Xue-Qing LIU ; Jia-Min ZHOU ; Miao HE ; Jing LI ; Xia-Li SHAO ; Wen-Hui LI ; Yu-Zhou GUAN ; Wei-Hong ZHANG ; Feng FENG
Acta Academiae Medicinae Sinicae 2025;47(2):219-225
Objective To investigate the alterations of cerebral blood flow(CBF)in type 2 diabetic mellitus(T2DM) patients without cognitive impairment by using arterial spin labeling(ASL)technique.Methods A total of 23 T2DM patients without cognitive impairment and 23 healthy controls(HC)matched by age,sex,and education attainment were recruited.Their clinical data were collected,and neuropsychological tests and cerebral magnetic resonance imaging were performed.Then,the outcomes of clinical features,neuropsychological tests,and global and regional CBF were compared between the two groups.The significant regional zCBF(z-transformed relative CBF)values were extracted and correlated with clinical data and neuropsychological scores in T2DM patients,controlling age,sex,and education.Results No significant difference was found in whole brain CBF between the two groups(P=0.155),while significantly higher CBF was identified in the left superior temporal gyrus and left insula in the T2DM group(Gaussian random field correction,initial threshold P < 0.001,cluster level P < 0.05).No correlation was observed between the significant regional zCBF values and the clinical data or the neuropsychological scores in T2DM patients(all P>0.05).Conclusion Alterations in cerebral hemodynamics may precede cognitive function changes in T2DM,suggesting that the ASL technique is promising for early monitoring of cerebral hemodynamic changes associated with cognitive impairment in patients with T2DM.
Humans
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Diabetes Mellitus, Type 2/physiopathology*
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Cerebrovascular Circulation
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Middle Aged
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Male
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Female
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Magnetic Resonance Imaging
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Case-Control Studies
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Cognitive Dysfunction
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Neuropsychological Tests
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Aged
3.Establishment of a Multiplex Detection Method for Common Bacteria in Blood Based on Human Mannan-Binding Lectin Protein-Conjugated Magnetic Bead Enrichment Combined with Recombinase-Aided PCR Technology
Jin Zi ZHAO ; Ping Xiao CHEN ; Wei Shao HUA ; Yu Feng LI ; Meng ZHAO ; Hao Chen XING ; Jie WANG ; Yu Feng TIAN ; Qing Rui ZHANG ; Na Xiao LYU ; Qiang Zhi HAN ; Xin Yu WANG ; Yi Hong LI ; Xin Xin SHEN ; Jun Xue MA ; Qing Yan TIE
Biomedical and Environmental Sciences 2024;37(4):387-398
Objective Recombinase-aided polymerase chain reaction(RAP)is a sensitive,single-tube,two-stage nucleic acid amplification method.This study aimed to develop an assay that can be used for the early diagnosis of three types of bacteremia caused by Staphylococcus aureus(SA),Pseudomonas aeruginosa(PA),and Acinetobacter baumannii(AB)in the bloodstream based on recombinant human mannan-binding lectin protein(M1 protein)-conjugated magnetic bead(M1 bead)enrichment of pathogens combined with RAP. Methods Recombinant plasmids were used to evaluate the assay sensitivity.Common blood influenza bacteria were used for the specific detection.Simulated and clinical plasma samples were enriched with M1 beads and then subjected to multiple recombinase-aided PCR(M-RAP)and quantitative PCR(qPCR)assays.Kappa analysis was used to evaluate the consistency between the two assays. Results The M-RAP method had sensitivity rates of 1,10,and 1 copies/μL for the detection of SA,PA,and AB plasmids,respectively,without cross-reaction to other bacterial species.The M-RAP assay obtained results for<10 CFU/mL pathogens in the blood within 4 h,with higher sensitivity than qPCR.M-RAP and qPCR for SA,PA,and AB yielded Kappa values of 0.839,0.815,and 0.856,respectively(P<0.05). Conclusion An M-RAP assay for SA,PA,and AB in blood samples utilizing M1 bead enrichment has been developed and can be potentially used for the early detection of bacteremia.
4. Mechanism of EGFR inhibitor AG1478 combined with oxaliplatin in inhibiting PI3K/AKT pathway and promoting autophagy in HI 975 cells
Jin-Qing HUANG ; Yang LI ; Dong-Xue WEI ; Shan JIANG ; Shao-Feng JIANG
Chinese Pharmacological Bulletin 2024;40(2):242-278
Aim To explore the effect of oxaliplatin combined with epidermal growth factor receptor tyrosine kinase inhibitor AG1478 on autophagy in non-small cell lung cancer H1975 cells. Methods H1975 cells were cultured in vitro using gradient concentrations of AG1478 (0, 5, 10, 15, 20, 25, 30, 35, 40 jjimol • IT
5.Research progress of PPAR-γ regulating brain cholesterol metabolism to clear β-amyloid protein to improve Alzheimer's disease
Xue-Qing DUAN ; Shao-Feng WANG ; Xian-Yu CHEN ; Yan-Wei HAO ; Jia-Xin LI ; Li LI ; Shi-Jun XU ; Bin LI
Chinese Pharmacological Bulletin 2024;40(11):2005-2009
Peroxisome proliferator-activated receptor gamma(PPAR-γ)is a member of the ligand-activated nuclear tran-scription factor superfamily.Activated PPAR-γ is involved in the regulation of many central nervous system(CNS)events,and is involved in cholesterol metabolism by inducing or inhibi-ting a series of gene pathways,thereby inhibiting the deposition of β-amyloid protein(Aβ).It plays an important neuroprotec-tive role in Alzheimer's disease(AD),improves memory and cognition in AD,and is a potential target for AD.Drug develop-ment aimed at restoring cholesterol homeostasis may be a poten-tial strategy to counteract AD.By analyzing the distribution and structure of PPAR-γ,focusing on the biological correlation be-tween PPAR-γ-mediated cholesterol metabolism and AD,this paper describes the mechanism regulation of PPAR-γ on key proteins,genes and their corresponding molecules,providing a new reference for the treatment of AD.
6.Safety of high-carbohydrate fluid diet 2 h versus overnight fasting before non-emergency endoscopic retrograde cholangiopancreatography: A single-blind, multicenter, randomized controlled trial
Wenbo MENG ; W. Joseph LEUNG ; Zhenyu WANG ; Qiyong LI ; Leida ZHANG ; Kai ZHANG ; Xuefeng WANG ; Meng WANG ; Qi WANG ; Yingmei SHAO ; Jijun ZHANG ; Ping YUE ; Lei ZHANG ; Kexiang ZHU ; Xiaoliang ZHU ; Hui ZHANG ; Senlin HOU ; Kailin CAI ; Hao SUN ; Ping XUE ; Wei LIU ; Haiping WANG ; Li ZHANG ; Songming DING ; Zhiqing YANG ; Ming ZHANG ; Hao WENG ; Qingyuan WU ; Bendong CHEN ; Tiemin JIANG ; Yingkai WANG ; Lichao ZHANG ; Ke WU ; Xue YANG ; Zilong WEN ; Chun LIU ; Long MIAO ; Zhengfeng WANG ; Jiajia LI ; Xiaowen YAN ; Fangzhao WANG ; Lingen ZHANG ; Mingzhen BAI ; Ningning MI ; Xianzhuo ZHANG ; Wence ZHOU ; Jinqiu YUAN ; Azumi SUZUKI ; Kiyohito TANAKA ; Jiankang LIU ; Ula NUR ; Elisabete WEIDERPASS ; Xun LI
Chinese Medical Journal 2024;137(12):1437-1446
Background::Although overnight fasting is recommended prior to endoscopic retrograde cholangiopancreatography (ERCP), the benefits and safety of high-carbohydrate fluid diet (CFD) intake 2 h before ERCP remain unclear. This study aimed to analyze whether high-CFD intake 2 h before ERCP can be safe and accelerate patients’ recovery.Methods::This prospective, multicenter, randomized controlled trial involved 15 tertiary ERCP centers. A total of 1330 patients were randomized into CFD group ( n = 665) and fasting group ( n = 665). The CFD group received 400 mL of maltodextrin orally 2 h before ERCP, while the control group abstained from food/water overnight (>6 h) before ERCP. All ERCP procedures were performed using deep sedation with intravenous propofol. The investigators were blinded but not the patients. The primary outcomes included postoperative fatigue and abdominal pain score, and the secondary outcomes included complications and changes in metabolic indicators. The outcomes were analyzed according to a modified intention-to-treat principle. Results::The post-ERCP fatigue scores were significantly lower at 4 h (4.1 ± 2.6 vs. 4.8 ± 2.8, t = 4.23, P <0.001) and 20 h (2.4 ± 2.1 vs. 3.4 ± 2.4, t= 7.94, P <0.001) in the CFD group, with least-squares mean differences of 0.48 (95% confidence interval [CI]: 0.26–0.71, P <0.001) and 0.76 (95% CI: 0.57–0.95, P <0.001), respectively. The 4-h pain scores (2.1 ± 1.7 vs. 2.2 ± 1.7, t = 2.60, P = 0.009, with a least-squares mean difference of 0.21 [95% CI: 0.05–0.37]) and positive urine ketone levels (7.7% [39/509] vs. 15.4% [82/533], χ2 = 15.13, P <0.001) were lower in the CFD group. The CFD group had significantly less cholangitis (2.1% [13/634] vs. 4.0% [26/658], χ2 = 3.99, P = 0.046) but not pancreatitis (5.5% [35/634] vs. 6.5% [43/658], χ2 = 0.59, P = 0.444). Subgroup analysis revealed that CFD reduced the incidence of complications in patients with native papilla (odds ratio [OR]: 0.61, 95% CI: 0.39–0.95, P = 0.028) in the multivariable models. Conclusion::Ingesting 400 mL of CFD 2 h before ERCP is safe, with a reduction in post-ERCP fatigue, abdominal pain, and cholangitis during recovery.Trail Registration::ClinicalTrials.gov, No. NCT03075280.
7.Contralateral endoscopic approach for lumbar foraminal stenosis using unilateral biportal endoscopic surgery
Wei CHENG ; Rong-Xue SHAO ; Cheng-Yue ZHU ; Dong WANG ; Wei ZHANG ; Hao PAN
China Journal of Orthopaedics and Traumatology 2024;37(4):331-337
Objective To assess the feasibility and imaging outcomes of unilateral biportal endoscopic technique in the treatment of lumbar foraminal stenosis through contralateral approach.Methods The clinical data of 33 patients with lumbar foraminal stenosis treated with unilateral biportal endoscopic technique from January 2021 to July 2022 were retrospectively analyzed.There were 17 males and 16 females;age ranging from 34 to 72 years old with an average of(56.00±7.89)years old;operation time and perioperative complications were recorded;visual analogue scale(VAS)of pain was recorded,to evaluate the degree of low back pain and lower extremity pain,and Oswestry disability index(ODI)to evaluate the lumbar spine func-tion.At the latest follow-up,the modified Macnab score was used to evaluate the clinical efficacy.Results All patients success-fully completed the operation.The operation time ranged from 47 to 65 minutes,with an average of(56.10±5.19)minutes.The postoperative follow-up ranged from 12 to 18 months,with an average of(14.9±2.3)months.The VAS of low back and lower extermity pain before operation were(7.273±1.442)and(7.697±1.447)scores,ODI was(69.182±9.740)%.Postoperative lumbocrural pain VAS were(3.394±0.966)and(2.818±0.727)scores,ODI was(17.30±4.78)%.At the latest follow-up,VAS of back and lower extermity pain was(2.788±0.650)and(2.394±0.704)scores,ODI was(14.33±350)%.There were signifi-cant differences in VAS of low back and lower extremity pain and ODI before and after operation(P<0.05).At the latest follow-up,according to the modified Macnab criteria,24 patients got excellent result,5 as good,2 as fair,and 2 as poor.Conclusion Unilateral biportal endoscopic treatment of lumbar foraminal stenosis through the contralateral approach is a safe and efficient method,with few complications,quick postoperative recovery,and satisfactory clinical outcomes.During the follow-up period,no iatrogenic lumbar instability was observed.
8.Comparison on radiation doses of in vitro pre-fenestration and in situ fenestration thoracic endovascular aortic repair in treatment of aortic disease
Fang XUE ; Xiaofeng HAN ; Gang WANG ; Lei SHAO ; Guangrui LIU ; Tiezheng LI ; Xi GUO ; Wei QIU ; Xiaohai MA
Chinese Journal of Interventional Imaging and Therapy 2024;21(9):553-556
Objective To compare the radiation dose of in vitro pre-fenestration and in situ fenestration thoracic endovascular aortic repair(TEVAR)in treatment of aortic disease.Methods Data of 51 patients with aortic diseases who received in vitro pre-fenestration(group A)and 21 cases who underwent in situ fenestration(group B)TEVAR were retrospectively analyzed.The fluoroscopy duration,total reference air kerma(AK),total dose area product(DAP)and TEVAR time were compared between groups.Results TEVAR was successfully completed in all 72 patients.Fluoroscopy duration([21.42±8.04]min vs.[34.57±9.07]min)and total DAP(44315.0[31157.0,56307.5]μGy·m2 vs.72153.0[45460.0,82354.0]μGy·m2)in group A were both significantly lower than those in group B(both P<0.05),while total AK(2423[1638,3533]mGy vs.3600[1898,3921]mGy)and TEVAR time([83.41±22.89]min vs.[81.00±22.13]min)in group A were not significant different from those in group B(both P>0.05).Conclusion Compared with in situ fenestration TEVAR,both the fluoroscopy time and total DAP of in vitro pre-fenestration TEVAR significantly reduced for treating aortic diseases.
9.Surveillance of bacterial resistance in tertiary hospitals across China:results of CHINET Antimicrobial Resistance Surveillance Program in 2022
Yan GUO ; Fupin HU ; Demei ZHU ; Fu WANG ; Xiaofei JIANG ; Yingchun XU ; Xiaojiang ZHANG ; Fengbo ZHANG ; Ping JI ; Yi XIE ; Yuling XIAO ; Chuanqing WANG ; Pan FU ; Yuanhong XU ; Ying HUANG ; Ziyong SUN ; Zhongju CHEN ; Jingyong SUN ; Qing CHEN ; Yunzhuo CHU ; Sufei TIAN ; Zhidong HU ; Jin LI ; Yunsong YU ; Jie LIN ; Bin SHAN ; Yunmin XU ; Sufang GUO ; Yanyan WANG ; Lianhua WEI ; Keke LI ; Hong ZHANG ; Fen PAN ; Yunjian HU ; Xiaoman AI ; Chao ZHUO ; Danhong SU ; Dawen GUO ; Jinying ZHAO ; Hua YU ; Xiangning HUANG ; Wen'en LIU ; Yanming LI ; Yan JIN ; Chunhong SHAO ; Xuesong XU ; Wei LI ; Shanmei WANG ; Yafei CHU ; Lixia ZHANG ; Juan MA ; Shuping ZHOU ; Yan ZHOU ; Lei ZHU ; Jinhua MENG ; Fang DONG ; Zhiyong LÜ ; Fangfang HU ; Han SHEN ; Wanqing ZHOU ; Wei JIA ; Gang LI ; Jinsong WU ; Yuemei LU ; Jihong LI ; Qian SUN ; Jinju DUAN ; Jianbang KANG ; Xiaobo MA ; Yanqing ZHENG ; Ruyi GUO ; Yan ZHU ; Yunsheng CHEN ; Qing MENG ; Shifu WANG ; Xuefei HU ; Wenhui HUANG ; Juan LI ; Quangui SHI ; Juan YANG ; Abulimiti REZIWAGULI ; Lili HUANG ; Xuejun SHAO ; Xiaoyan REN ; Dong LI ; Qun ZHANG ; Xue CHEN ; Rihai LI ; Jieli XU ; Kaijie GAO ; Lu XU ; Lin LIN ; Zhuo ZHANG ; Jianlong LIU ; Min FU ; Yinghui GUO ; Wenchao ZHANG ; Zengguo WANG ; Kai JIA ; Yun XIA ; Shan SUN ; Huimin YANG ; Yan MIAO ; Mingming ZHOU ; Shihai ZHANG ; Hongjuan LIU ; Nan CHEN ; Chan LI ; Jilu SHEN ; Wanqi MEN ; Peng WANG ; Xiaowei ZHANG ; Yanyan LIU ; Yong AN
Chinese Journal of Infection and Chemotherapy 2024;24(3):277-286
Objective To monitor the susceptibility of clinical isolates to antimicrobial agents in tertiary hospitals in major regions of China in 2022.Methods Clinical isolates from 58 hospitals in China were tested for antimicrobial susceptibility using a unified protocol based on disc diffusion method or automated testing systems.Results were interpreted using the 2022 Clinical &Laboratory Standards Institute(CLSI)breakpoints.Results A total of 318 013 clinical isolates were collected from January 1,2022 to December 31,2022,of which 29.5%were gram-positive and 70.5%were gram-negative.The prevalence of methicillin-resistant strains in Staphylococcus aureus,Staphylococcus epidermidis and other coagulase-negative Staphylococcus species(excluding Staphylococcus pseudintermedius and Staphylococcus schleiferi)was 28.3%,76.7%and 77.9%,respectively.Overall,94.0%of MRSA strains were susceptible to trimethoprim-sulfamethoxazole and 90.8%of MRSE strains were susceptible to rifampicin.No vancomycin-resistant strains were found.Enterococcus faecalis showed significantly lower resistance rates to most antimicrobial agents tested than Enterococcus faecium.A few vancomycin-resistant strains were identified in both E.faecalis and E.faecium.The prevalence of penicillin-susceptible Streptococcus pneumoniae was 94.2%in the isolates from children and 95.7%in the isolates from adults.The resistance rate to carbapenems was lower than 13.1%in most Enterobacterales species except for Klebsiella,21.7%-23.1%of which were resistant to carbapenems.Most Enterobacterales isolates were highly susceptible to tigecycline,colistin and polymyxin B,with resistance rates ranging from 0.1%to 13.3%.The prevalence of meropenem-resistant strains decreased from 23.5%in 2019 to 18.0%in 2022 in Pseudomonas aeruginosa,and decreased from 79.0%in 2019 to 72.5%in 2022 in Acinetobacter baumannii.Conclusions The resistance of clinical isolates to the commonly used antimicrobial agents is still increasing in tertiary hospitals.However,the prevalence of important carbapenem-resistant organisms such as carbapenem-resistant K.pneumoniae,P.aeruginosa,and A.baumannii showed a downward trend in recent years.This finding suggests that the strategy of combining antimicrobial resistance surveillance with multidisciplinary concerted action works well in curbing the spread of resistant bacteria.
10.Changing distribution and resistance profiles of common pathogens isolated from urine in the CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Yanming LI ; Mingxiang ZOU ; Wen'en LIU ; Yang YANG ; Fupin HU ; Demei ZHU ; Yingchun XU ; Xiaojiang ZHANG ; Fengbo ZHANG ; Ping JI ; Yi XIE ; Mei KANG ; Chuanqing WANG ; Pan FU ; Yuanhong XU ; Ying HUANG ; Ziyong SUN ; Zhongju CHEN ; Yuxing NI ; Jingyong SUN ; Yunzhuo CHU ; Sufei TIAN ; Zhidong HU ; Jin LI ; Yunsong YU ; Jie LIN ; Bin SHAN ; Yan DU ; Sufang GUO ; Lianhua WEI ; Fengmei ZOU ; Hong ZHANG ; Chun WANG ; Yunjian HU ; Xiaoman AI ; Chao ZHUO ; Danhong SU ; Dawen GUO ; Jinying ZHAO ; Hua YU ; Xiangning HUANG ; Yan JIN ; Chunhong SHAO ; Xuesong XU ; Chao YAN ; Shanmei WANG ; Yafei CHU ; Lixia ZHANG ; Juan MA ; Shuping ZHOU ; Yan ZHOU ; Lei ZHU ; Jinhua MENG ; Fang DONG ; Zhiyong LÜ ; Fangfang HU ; Han SHEN ; Wanqing ZHOU ; Wei JIA ; Gang LI ; Jinsong WU ; Yuemei LU ; Jihong LI ; Jinju DUAN ; Jianbang KANG ; Xiaobo MA ; Yanping ZHENG ; Ruyi GUO ; Yan ZHU ; Yunsheng CHEN ; Qing MENG ; Shifu WANG ; Xuefei HU ; Jilu SHEN ; Ruizhong WANG ; Hua FANG ; Bixia YU ; Yong ZHAO ; Ping GONG ; Kaizhen WENG ; Yirong ZHANG ; Jiangshan LIU ; Longfeng LIAO ; Hongqin GU ; Lin JIANG ; Wen HE ; Shunhong XUE ; Jiao FENG ; Chunlei YUE
Chinese Journal of Infection and Chemotherapy 2024;24(3):287-299
Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8%(62 219/261 893),and gram-negative bacteria 76.2%(199 674/261 893).The most common species were E.coli(46.7%),E.faecium(10.4%),K.pneumoniae(9.8%),E.faecalis(8.7%),P.mirabilis(3.5%),P.aeruginosa(3.4%),SS.agalactiae(2.6%),and E.cloacae(2.1%).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2%,52.8%and 37.0%,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7%,18.5%,16.4%,and 40.3%,respectively.Lower than 10%of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90%of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was<2%.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

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