1.Research Advances in Construction Methods and Novel Technologies for Animal Models of Pulmonary Hypertension
Ziyi CHEN ; Hongyan SUN ; Pinfang KANG ; Wenjuan WU
Laboratory Animal and Comparative Medicine 2026;46(1):81-93
Pulmonary hypertension (PH), marked by sustained elevation of pulmonary artery pressure, imposes a heavy burden on the right ventricle and may culminate in right heart failure. Its pathogenesis is multifaceted, encompassing endothelial dysfunction, vascular smooth muscle proliferation, inflammation, thrombosis, and genetic factors. Animal models serve as core tools for exploring PH mechanisms and therapies, each with unique strengths and limitations. The single-dose monocrotaline (MCT) model is one of the most commonly used experimental animal models of PH and is widely applied in mechanistic studies, drug screening, and efficacy evaluation; it offers simplicity and cost-effectiveness, can induce PH within a short period, yet its pathophysiology differs to some extent from human idiopathic PH. In contrast, the Sugen5416 combined with chronic hypoxia model better mimics PH progression by placing animals under hypoxic conditions to induce pulmonary vasoconstriction and vascular remodeling, but it requires a longer modelling time, and the degree of hypoxia has a substantial impact on experimental outcomes. Beyond these two commonly used modeling approaches, a variety of emerging techniques have been applied in PH research; gene-editing technologies enable precise investigation of specific gene functions in PH. Additionally, induced pluripotent stem cell-based 3D organoid technology allows for individualized modelling while preserving patients' genetic information for precise clinical translation. Each model or technology can simulate different aspects of the pathological processes of human PH, and their findings provide key insights into the nature of the disease and serve as an important platform for the development of novel therapeutic targets. This paper comprehensively describes various animal models and emerging technologies used in PH research, analyzing their characteristics, applications, and limitations, with the aim of providing experimental and technical support for the development of new therapeutic strategies and drugs.
2.Research Progress of Glioma in China in 2024
Xiaoman KANG ; Junlin LI ; Wenlin CHEN ; Shanmu JIN ; Yilin LI ; Jiahui LIU ; Yulu GE ; Wenbo WU ; Jiaheng LI ; Yiming LIAN ; Yu WANG ; Wenbin MA
Medical Journal of Peking Union Medical College Hospital 2025;16(6):1437-1448
Glioma is the most common primary malignant tumor of the central nervous system in adults. Despite the standard treatment of surgery combined with radiotherapy and chemotherapy, the prognosis for high-grade glioma patients remains poor, highlighting the urgent need to further explore its pathogenesis and develop new therapeutic strategies. This article reviews the research progress in the field of glioma in China in 2024, covering tumorigenesis mechanisms, tumor immune microenvironment composition, advances in imaging techniques and novel imaging agents, improvements in surgical approaches, mechanisms of radio- and chemoresistance, and explorations of new therapeutic modalities. These studies provide a solid theoretical foundation for advancing clinical diagnosis and treatment of gliomas and may offer new opportunities to improve patient outcomes.
3.Adiponectin regulates ovarian cancer cell proliferation,migration,and invasion via the PI3K/Akt/mTOR signaling pathway
Yixin LIN ; Xiaoqian ZHU ; Xinger WU ; Kang CHEN
International Journal of Laboratory Medicine 2025;46(19):2319-2325
Objective To investigate the effects of adiponectin(APN)on the proliferation,migration,and invasion of ovarian cancer cells and its potential association with the phosphatidylinositol 3-kinase(PI3K)/pro-tein kinase B(Akt)/mammalian target of rapamycin(mTOR)signaling pathway.Methods A2780 and SK-OV3 cell lines were selected.AdipoR1 mRNA expression was detected by real-time polymerase chain reaction(RT-PCR).The CCK-8 assay was employed to evaluate APN-induced proliferation,while scratch wound heal-ing and Transwell assays were conducted to assess migration and invasion capabilities.Western blot analysis was performed to measure the expression levels of PI3K,Akt,mTOR,and their phosphorylated forms(p-Akt,p-mTOR)at different time points(0-60 min)after APN treatment and across intervention groups(APN,LY294002,APN+LY294002).Results Both A2780 and SKOV3 cells expressed AdipoR1 mRNA.Compared with the control group,APN significantly enhanced the proliferation,migration,and invasion of o-varian cancer cells(P<0.05).Under the stimulation of APN,the expression levels of p-Akt and p-mTOR in A2780 and SKOV3 cells showed a significant upward trend.The peak expression of p-Akt and p-mTOR in A2780 cells was observed at 30 minutes,while in SKOV3 cells,it occurred at 60 minutes.The expression lev-els of p-Akt and p-mTOR were significantly reduced in the LY294002 group and APN+LY294002 group(P<0.001).Conclusion APN enhances the proliferation,migration,and invasion behavior of ovarian cancer cells by activating the PI3K/Akt/mTOR signaling pathway,and its effect can be reversed by PI3K inhibitors,providing a theoretical basis for targeted intervention in ovarian cancer progression.
4.Design and application of novel protective ventilator circuit component
Wei-zhou WU ; Kang LU ; Jing-jie CAO ; Zhi-hua ZHAO ; Hai-tao LAN ; Zan-chao CHEN ; Qing-feng XUE
Chinese Medical Equipment Journal 2025;46(4):113-117
Objective To develop a novel protective ventilator circuit component and to verify its performance by water seal and anti-splash experiments.Methods A novel protective ventilator circuit component had a design scheme with the multifunctional joint,and consisted of a tee connection tube,an isolation sleeve and a stop sleeve,of which,the tee connection tube was made of polyethylene polymer material and the others were made of silicone material.The tee connection tube had a T-shaped structure with two standard connection ports,which was composed of an adapter,a sealing cap,a plug and a sealing ring;the isolation sleeve was in the shape of a cylinder with a raised bottom,which was inserted into the adapter;the stop sleeve was located in the isolation sleeve,with an inverted frustum of a cone at the bottom and a rounded hole in the middle of the inverted frustum.An open ventilator circuit tube was involved in the performance verification of the circuit component developed.In the water seal experiment,sputum aspiration was simulated and the heights of the liquid level drop in the L-shaped tubes were compared after sputum aspiration.In the anti-splash experiment,the infection rates on the surfaces of the sterile hole towels and gloves were calculated.Results Water seal experiment showed after sputum aspiration the open ventilator circuit tube had the liquid level at the L-shaped tube higher significantly than that of the circuit component;the anti-splash experiment indicated sputum aspiration resulted in the occurance of the splashing out of the secretion and 77.5%infection rate by the open ventilator circuit tube,while no splashing out and 0%infection rate by the circuit component developed.Conclusion The novel protective ventilator circuit component behaves well in sealing and anti-splashing,and thus is worthy of clinical application for sputum aspiration.[Chinese Medical Equipment Journal,2025,46(4):113-117]
5.Expression characteristics of OPG/RANKL/RANK and the relationship with fibrosis in myocardial tissues of rats with chronic heart failure
Xin YANG ; Xue-kun CAI ; Ze-long WU ; An-tao CHEN ; Zi-hao CHEN ; Xuan XIE ; Jia-kang OU ; Zhao-qi HUANG
The Chinese Journal of Clinical Pharmacology 2025;41(1):71-75
Objective To study the expression characteristics of osteoprotegerin(OPG)/receptor activator of nuclear factor-κB ligand(RANKL)/receptor activator of nuclear factor-κB(RANK)system and the relationship with fibrosis in myocardial tissues of rats with chronic heart failure.Methods SD rats were randomly divided into sham-operation group(12 rats)and model group.In sham-operation group,surgical thread was passed through the abdominal aorta without constricting it after laparotomy;in model group,establish the heart failure model by abdominal aorta coarctation.The successful model rats were randomly divided into model 1 week(12 rats),model 2 weeks(11 rats),model 4 weeks(11 rats),model 8 weeks(11 rats)and model 12 weeks groups(11 rats).The end point of the study is at week 12.The contents of hydroxyproline(HYP),total myocardial collagen and collagen volume fraction(CVF)were compaired in all proups.The expression levels of OPG,RANKL and RANK proteins in cardiomyocytes were determined by Western blot.Results The contents of HYP in sham-operation,model 1 week,model 2 weeks,model 4 weeks,model 8 weeks and model 12 weeks group were(0.25±0.04),(0.37±0.05),(0.45±0.04),(0.60±0.05),(0.82±0.10)and(1.03±0.07)μg·mg-1;the total myocardial collagen contents were(1.87±0.31),(2.73±0.38),(3.36±0.31),(4.47±0.37),(6.08±0.74)and(7.67±0.49)μg·mg-1;the CVF were(1.95±0.23)%,(2.40±0.25)%,(3.65±0.25)%,(5.43±0.29)%,(6.97±0.36)%and(9.38±0.49)%;the relative expression levels of OPG protein were 0.64±0.07,0.80±0.07,1.02±0.07,1.32±0.11,2.13±0.12 and 2.84±0.16;the relative expression levels of RANKL protein were 0.71±0.08,1.06±0.07,1.53±0.07,2.62±0.12,4.46±0.14 and 6.11±0.16;the relative expression levels of RANK protein were 0.30±0.05,0.45±0.05,0.63±0.06,0.98±0.07,1.43±0.10 and 1.63±0.10.With the extention of time,the above indexs of all model groups were significantly higher than those in the sham-operation group(all P<0.05).There were positive linear correlation between the relative expression levels of OPG,RANKL,RANK protein and the levels of CVF and total contents in cardiomyocytes of rats with chronic heart failure(allP<0.01).Conclusions In the process of chronic heart failure,the expression of OPG/RANKL/RANK axis is obviously enhanced,in which the up-regulation of RANKL level is most obvious.The expression level of OPG/RANKL/RANK is positively correlated with CVF and total myocardial collagen content.
6.Analysis of factors affecting long-term survival in patients with anaplastic thyroid carcinoma and the efficacy of immunotherapy
Jian BU ; Kang NING ; Yongchao YU ; Zan JIAO ; Tong WU ; Zhongyuan YANG ; Weichao CHEN ; Ankui YANG
Chinese Journal of Oncology 2025;47(8):756-762
Objective:To explore the long-term survival outcomes of patients with anaplastic thyroid cancer (ATC) and analyze key factors influencing the prognosis.Methods:A retrospective analysis was conducted on the clinical and follow-up data of 77 ATC patients treated at the Sun Yat-sen University Cancer Center from March 2000 to July 2022, with tumor-specific survival as the primary endpoint. The Kaplan-Meier method was used to plot the survival curves, and univariate and multivariate Cox regression analyses were performed to identify the prognostic factors.Results:Among the 77 patients, 64 underwent surgical treatment, with 33 receiving surgery alone, 8 undergoing surgery combined with chemotherapy, 13 undergoing surgery with radiotherapy, 1 undergoing surgery with chemotherapy and radiotherapy, 2 receiving surgery combined with chemotherapy and targeted therapy, 3 receiving surgery with targeted therapy, and 4 receiving surgery with immunotherapy and targeted therapy. Among the 13 patients who did not undergo surgery, 2 received chemotherapy alone, 3 received targeted therapy alone, 1 received immunotherapy alone, 1 received chemoradiotherapy, 5 received chemotherapy combined with immunotherapy, and 1 received immunotherapy combined with targeted therapy. The median follow-up time was 8.4 months, with 58 patients (75.3%) died, and the median survival time was 6.63 months. Univariate Cox regression analysis showed that C-reactive protein, monocyte count, lymphocyte count, abnormal albumin levels, the maximum diameter of the primary tumor, BMI, and whether immunotherapy was administered were significantly associated with survival in ATC patients (all P<0.05). Multivariate Cox regression analysis indicated that immunotherapy was an independent factor for survival in ATC patients ( HR=0.18, 95% CI: 0.05-0.62, P=0.007). Among the 40 patients admitted after 2015, the 11 patients who received immunotherapy had a median survival time of 17.2 months, which was superior to the 29 patients who did not receive this treatment (median survival time 6.2 months, P=0.03). Conclusions:ATC patients receiving immunotherapy had a better prognosis and longer survival. Additionally, elevated C-reactive protein, abnormal albumin, monocyte count, lymphocyte count, and BMI might be associated with poorer prognosis in ATC. Tailoring treatment based on the individual characteristics of ATC patients may be beneficial for their long-term survival.
7.Changing resistance profiles of Haemophilus influenzae and Moraxella catarrhalis isolates in hospitals across China:results from the CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Hui FAN ; Chunhong SHAO ; Jia WANG ; Yang YANG ; Fupin HU ; Demei ZHU ; Yunsheng CHEN ; Qing MENG ; Hong ZHANG ; Chun WANG ; Fang DONG ; Wenqi SONG ; Kaizhen WEN ; Yirong ZHANG ; Chuanqing WANG ; Pan FU ; Chao ZHUO ; Danhong SU ; Jiangwei KE ; Shuping ZHOU ; Hua ZHANG ; Fangfang HU ; Mei KANG ; Chao HE ; Hua YU ; Xiangning HUANG ; Yingchun XU ; Xiaojiang ZHANG ; Wenen LIU ; Yanming LI ; Lei ZHU ; Jinhua MENG ; Shifu WANG ; Bin SHAN ; Yan DU ; Wei JIA ; Gang LI ; Jiao FENG ; Ping GONG ; Miao SONG ; Lianhua WEI ; Xin WANG ; Ruizhong WANG ; Hua FANG ; Sufang GUO ; Yanyan WANG ; Dawen GUO ; Jinying ZHAO ; Lixia ZHANG ; Juan MA ; Han SHEN ; Wanqing ZHOU ; Ruyi GUO ; Yan ZHU ; Jinsong WU ; Yuemei LU ; Yuxing NI ; Jingrong SUN ; Xiaobo MA ; Yanqing ZHENG ; Yunsong YU ; Jie LIN ; Ziyong SUN ; Zhongju CHEN ; Zhidong HU ; Jin LI ; Fengbo ZHANG ; Ping JI ; Yunjian HU ; Xiaoman AI ; Jinju DUAN ; Jianbang KANG ; Xuefei HU ; Xuesong XU ; Chao YAN ; Yi LI ; Shanmei WANG ; Hongqin GU ; Yuanhong XU ; Ying HUANG ; Yunzhuo CHU ; Sufei TIAN ; Jihong LI ; Bixia YU ; Cunshan KOU ; Jilu SHEN ; Wenhui HUANG ; Xiuli YANG ; Likang ZHU ; Lin JIANG ; Wen HE ; Chunlei YUE
Chinese Journal of Infection and Chemotherapy 2025;25(1):30-38
Objective To investigate the distribution and antimicrobial resistance profiles of clinically isolated Haemophilus influenzae and Moraxella catarrhalis in hospitals across China from 2015 to 2021,and provide evidence for rational use of antimicrobial agents.Methods Data of H.influenzae and M.catarrhalis strains isolated from 2015 to 2021 in CHINET program were collected for analysis,and antimicrobial susceptibility testing was performed by disc diffusion method or automated systems according to the uniform protocol of CHINET.The results were interpreted according to the CLSI breakpoints in 2022.Beta-lactamases was detected by using nitrocefin disk.Results From 2015 to 2021,a total of 43 642 strains of Haemophilus species were isolated,accounting for 2.91%of the total clinical isolates and 4.07%of Gram-negative bacteria in CHINET program.Among the 40 437 strains of H.influenzae,66.89%were isolated from children and 33.11%were isolated from adults.More than 90%of the H.influenzae strains were isolated from respiratory tract specimens.The prevalence of β-lactamase was 53.79%in H.influenzae strains.The H.influenzae strains isolated from children showed higher resistance rate than the strains isolated from adults.Overall,779 strains of H.influenzae did not produce β-lactamase but were resistant to ampicillin(BLNAR).Beta-lactamase-producing strains showed significantly higher resistance rates to these antimicrobial agents than the β-lactamase-nonproducing strains.Of the 16 191 M.catarrhalis strains,80.06%were isolated from children and 19.94%isolated from adults.M.catarrhalis strains were mostly susceptible to both amoxicillin-clavulanic acid and cefuroxime,evidenced by resistance rate lower than 2.0%.Conclusions The emergence of antibiotic-resistant H.influenzae due to β-lactamase production poses a challenge for clinical anti-infective treatment.Therefore,it is very important to implement antibiotic resistance surveillance for H.influenzae and guide rational antibiotic use.All local clinical microbiology laboratories should actively improve antibiotic susceptibility testing and strengthen antibiotic resistance surveillance for H.influenzae.
8.Changing distribution and antimicrobial resistance profiles of clinical isolates in children:results from the CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Qing MENG ; Lintao ZHOU ; Yunsheng CHEN ; Yang YANG ; Fupin HU ; Demei ZHU ; Chuanqing WANG ; Aimin WANG ; Lei ZHU ; Jinhua MENG ; Hong ZHANG ; Chun WANG ; Fang DONG ; Zhiyong LÜ ; Shuping ZHOU ; Yan ZHOU ; Shifu WANG ; Fangfang HU ; Yingchun XU ; Xiaojiang ZHANG ; Zhaoxia ZHANG ; Ping JI ; Wei JIA ; Gang LI ; Kaizhen WEN ; Yirong ZHANG ; Yan JIN ; Chunhong SHAO ; Yong ZHAO ; Ping GONG ; Chao ZHUO ; Danhong SU ; Bin SHAN ; Yan DU ; Sufang GUO ; Jiao FENG ; Ziyong SUN ; Zhongju CHEN ; Wen'en LIU ; Yanming LI ; Xiaobo MA ; Yanping ZHENG ; Dawen GUO ; Jinying ZHAO ; Ruizhong WANG ; Hua FANG ; Lixia ZHANG ; Juan MA ; Jihong LI ; Zhidong HU ; Jin LI ; Yuxing NI ; Jingyong SUN ; Ruyi GUO ; Yan ZHU ; Yi XIE ; Mei KANG ; Yuanhong XU ; Ying HUANG ; Shanmei WANG ; Yafei CHU ; Hua YU ; Xiangning HUANG ; Lianhua WEI ; Fengmei ZOU ; Han SHEN ; Wanqing ZHOU ; Yunzhuo CHU ; Sufei TIAN ; Shunhong XUE ; Hongqin GU ; Xuesong XU ; Chao YAN ; Bixia YU ; Jinju DUAN ; Jianbang KANG ; Jiangshan LIU ; Xuefei HU ; Yunsong YU ; Jie LIN ; Yunjian HU ; Xiaoman AI ; Chunlei YUE ; Jinsong WU ; Yuemei LU
Chinese Journal of Infection and Chemotherapy 2025;25(1):48-58
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.
9.Surveillance of antimicrobial resistance in clinical isolates of Escherichia coli:results from the CHINET Antimicrobial Resistance Surveillance Program,2015-2021
Shanmei WANG ; Bing MA ; Yi LI ; Yang YANG ; Fupin HU ; Demei ZHU ; Yingchun XU ; Xiaojiang ZHANG ; Zhaoxia ZHANG ; Ping JI ; Yi XIE ; Mei KANG ; Chuanqing WANG ; Aimin WANG ; 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 ; Wen'en LIU ; Yanming LI ; Yan JIN ; Chunhong SHAO ; Xuesong XU ; Chao YAN ; 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 ; Wenhui HUANG ; Ruizhong WANG ; Hua FANG ; Bixia YU ; Yong ZHAO ; Ping GONG ; Kaizhen WEN ; Yirong ZHANG ; Jiangshan LIU ; Longfeng LIAO ; Hongqin GU ; Lin JIANG ; Wen HE ; Shunhong XUE ; Jiao FENG ; Chunlei YUE
Chinese Journal of Infection and Chemotherapy 2025;25(1):39-47
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.
10.Isolation,identification,and biological characterization of enterotoxigenic Escherichia coli from a South China tiger
Jing-ru XU ; Zhi-hao ZHU ; Yu-qi LI ; Si-si FAN ; Ya-li KANG ; Yu-bin ZHUO ; Ling-shan HUANG ; Shu-qi QIU ; XUE-YUXI ; Xiao-ping WU ; Yu-ting LIAO ; Wei-ye LIN ; Xiao-ziyi XIAO ; Xue-jin LI ; Teng-teng CHEN ; Xi-pan LIN ; Kai-xiong LIN ; Ke-wei FAN
Chinese Journal of Zoonoses 2025;41(6):567-573
This study was aimed at identifying the pathogenic bacteria responsible for the death of a young tiger at the Fujian Meihua Mountain South China Tiger Breeding Research Institute.Tissue samples from the lungs,liver,and intestines of the deceased tiger were collected,and the bacteria were cultured inasterile environment.The bacterial strains were characterized according to their morphological and molecular biological properties,including assessment of virulence genes and antibiotic resistance genes,mouse lethality tests,and antibiotic susceptibility evaluations.A predominant bacterial strain isolated from the liver of the deceased tiger was identified as enterotoxigenic Escherichia coli(ETEC)strain Tiger22513F.Phylogenetic analysis of the 16S rRNA gene revealed that the Tiger22513F strain exhibited close genetic similarity to the reference strain ETEC(MF919609.1),with 99.9%nucleotide similarity,and resided on the same evolutionary branch.The Tiger22513F strain contained 11 antibiotic resistance genes(tetA,sul1,sul3,cmlA,floR,blaTEM,blaSHV,blaCMY-2,qnrA,qnrS,and qnrD)along with five virulence genes(VT1,fyuA,tsh,iucD,and ST).Mouse lethality tests indicated significant pathogenicity toward mice,affecting primarily the lungs,liver,and intestines.Antibiotic susceptibility testing demonstrated that this strain exhibited resistance to various classes of beta-lactam antibiotics,as well as quinolones and aminoglycosides.This investigation successfully isolated a multi-drug resistant enterotoxigenic Escherichia coli strain with pronounced pathogenicity from the liver of a deceased tiger;thus providing valuable scientific insights for clinical diagnosis,as well as prevention and control measures,against ETEC infections in South China tigers.

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