1.Differences in deltamethrin resistance and kdr gene mutation in Culex tritaeniorhynchus population in and outside the Yellow Sea wetland
Xiao-er ZHANG ; Zhi-ming WU ; Ye TIAN ; Qian CUI ; Yu-qian JI ; Huan WANG ; Shu-juan YANG ; Yi-chao ZHAO ; Yu WANG ; Hua-yu YIN ; Yu DING ; Guo-jin YAN ; Min-sen ZHAO ; Shou-gang ZHANG ; Bing-dong SONG ; Hong-na CHEN ; Jian GAO ; Wei-fang YANG ; Yu-fu ZHANG ; Hui LIU ; Hong-liang CHU
Acta Parasitologica et Medica Entomologica Sinica 2026;33(2):101-107
Objective To gain insights into the biological characteristics of different populations of Culex tritaeniorhynchus within and around the Yellow Sea wetland from the perspective of the occurrence of resistance, we investigated the levels of resistance to deltamethrin and kdr gene mutation in the wetland and its peripheral areas. Methods Specimens were collected from Cx. tritaeniorhynchus populations at two monitoring sites in the Rare Bird National Nature Reserve and Tiaozi Ni Wetland Scenic Area, and also from two populations in Yancheng City and the Liuhe District of Nanjing, and the resistance of these mosquitoes to deltamethrin was determined using the CDC biotest bottle method. For each concentration of deltamethrin assessed, a random subset of exposed specimens was selected for amplification of the kdr gene fragment, followed by Sanger sequencing to identify and analyze resistance-associated mutations. Results The LC50 levels of deltamethrin among mosquitoes from the four populations in Luhe, Yancheng, the Rare Bird National Nature Reserve and the Tiaozi Ni Wetland Scenic Area were 2.048 5, 7.798 2, 3.473 3, and 17.695 5 mg/mL, respectively, with corresponding concentrations of deltamethrin ranging from 0.005 to 5.000,0.050 to 50.000,0.050 to 25.000 and 0.050 to 50.000 mg/mL, respectively. Furthermore, the ranges of the KT50 values were 11.76-107.43, 67.05-216.30,29.77-107.43 and 28.40-329.51 min; the 1-h knockdown rates were 34.58%-99.15%, 9.52%-43.80%, 55.09%-73.01%, and 10.09%-68.07%; and the 24-h mortality rates were 12.15%-67.52%,9.52%-79.56%,13.17%-82.21%, and 11.01%-78.99%, respectively. With respect to kdr gene mutation, we assayed a total of 63,70,59, and 57 mosquitoes for the four populations, for which we detected L1014F mutation frequencies of 14.29%, 35.00%, 20.34%, and 31.58%, respectively, with a majority of these mutations being heterozygous for resistance. In addition, five adult mosquitoes were identified has having synonymous mutations at site 1011[i. e. , AAT(asparagine)mutation to AAC(asparagine)]. Conclusions Our findings revealed the clear resistance of Cx. tritaeniorhynchus to deltamethrin in the Yancheng region of the Yellow Sea wetland, and the resistance phenotype and kdr frequency of Cx. tritaeniorhynchus in the wetland environment were comparable to those of Cx. tritaeniorhynchus in the wetland environment, thereby indicating that the resistance of different populations of Cx. tritaeniorhynchus was homogeneous under the pressure of different insecticide selection within and around the wetland. However, the underlying mechanisms need to be further studied.
2.The first record of Anopheles messeae (Diptera: Culicidae) parasitized by water mites in China
Xue-ru CHEN ; Wen-zhen YAO ; Yu-hao LI ; Gui-chang LI ; Tao MENG ; Qun-ling FENG ; Xin-hui LIU ; Li-hong QIAO ; Xiang-ting WU ; Xue-feng ZHANG ; Cheng-lin LI ; Xue-cheng DONG ; Da-wei WANG ; Xiao-yan SI ; Yu-hong GUO
Acta Parasitologica et Medica Entomologica Sinica 2026;33(1):53-57
Objective This study reports on the obligatory parasitism of water mites Arrenurus sp. on Anopheles messeae at the Manzhouli Port, Inner Mongolia, China. Methods Duing July 2024, a survey on the mosquito diversity was conducted at the Manzhouli Port. Captured mosquitoes and their ectoparasites were identified to species level. Results A total of 1840 adult mosquitoes were collected, representing species from three genera: Culex(Cx. modestus, Cx. pipiens pallens), Aedes(Ae. dorsalis, Ae. flavidorsalis, Ae. flavescens), and Anopheles (An. messeae). Among all the mosqutioes specimens,3 out of 150 captured An. messeae were found to carry ectoparasitic mites, with number of 2,4,27 mites separately. Morphological and molecular identification reached the same result as water mites(Hydrachnidiae, Hydracrina). COI gene sequence showed 94% similarity with the closest species Arrenurus truncatellus. Conlusions Literature review suggests water mites are host-specific parasitism of mosquito species and herein with the first record of Arrenurus sp. parasiting on An. Messeae in the most high-latitude region globally.
3.Ameliorating effects of tetrahydrocurcumin and its nano-preparations on lipopolysaccharide-induced depression in mice
Hui Tan ; Yuanping Li ; Jingyuan Meng ; Tengteng Ma ; Yan Yang ; Zhengmao Yang ; Jiaqing Ma ; Jianping Xie ; Ying Guo
Acta Universitatis Medicinalis Anhui 2025;60(1):79-86
Objective :
To investigate the antidepressant effects and the underlying mechanisms of tetrahydrocurcumin(THC) and its nanoparticle formulation(THCN).
Methods :
Forty-six male ICR mice were randomly divided into Con group, LPS group, THC group, THCN group and SER group. A mouse depression model was established by intraperitoneal administration of LPS. The anxiety and depression-like behaviors of mice were evaluated by open field test(OFT) and forced swimming test(FST). Myelin staining was applied to assess the extent of demyelination in the prefrontal cortex of the mice. The prefrontal cortex and hippocampus were further examined for the expression levels of glial fibrillary acidic protein(GFAP) and Toll-like receptor 4(TLR4) through quantitative immunofluorescence assays.
Results :
Compared with the Con group, the LPS group showed increased anxiety-like and depressive-like behaviors in both the long-term and short-term experiments(P<0.05); the degree of demyelination increased in the LPS group of the long-term experiment(P<0.01); the expression of GFAP was reduced in the LPS group of the short-term experiment(P<0.01), while the expression of TLR4 increased(P<0.05); the expression of TLR4 decreased in the THC group(P<0.01); the expression of GFAP in the prefrontal cortex of the THCN group was reduced(P<0.01), while the expression of TLR4 increased(P<0.05). Compared with the LPS group, the THC group showed reduced depressive-like behaviors in the long-term experiment(P<0.05), while the anxiety-like and depressive-like behaviors of the THCN group and the SER group were reduced(P<0.05), and the anxiety-like and depressive-like behaviors of the THC group and the THCN group were reduced in the short-term experiment(P<0.05); the degree of demyelination was reduced in the THC group, THCN group and SER group in the long-term experiment(P<0.05); the expression of GFAP increased in the THC group of the short-term experiment(P<0.05), while the expression of TLR4 was reduced(P<0.05), and the expression of GFAP increased in the THCN group(P<0.05). Compared with the THC group, the THCN group and the SER group showed reduced anxiety-like behaviors in the long-term experiment(P<0.05); the expression of GFAP in the prefrontal cortex of the THCN group was reduced in the short-term experiment(P<0.05), while the expression of TLR4 in the hippocampal DG area increased in the short-term experiment(P<0.01).
Conclusion
Tetrahydrocurcumin and its nanoparticle formulation both exert significant ameliorative effects on depression-like behaviors and demyelination in mice induced by lipopolysaccharide. The antidepressant mechanism of THC appears to be mediated through the down-regulation of TLR4 and the up-regulation of GFAP. The mechanism underlying the antidepressant action of THCN seems predominantly focused on the enhancement of GFAP expression.
4.Constructing an induction educational system for clinical rotations in standardized pediatric residency training: program development and outcome evaluation
Ying LIAO ; Wei BAI ; Shan LI ; Guo YU ; Danyu SONG ; Hui YAN
Chinese Journal of Medical Education Research 2025;24(4):440-445
Objective:To construct a multimodal induction educational system suitable for standardized pediatric residency training bases, and to evaluate its effectiveness, thereby obtaining suggestions for further improvement.Methods:Twelve residents newly enrolled in the 2023 standardized residency training program who commenced their first-year training were included as study subjects. The induction educational system comprised multiple modules: department introduction, training plan and assessment requirements, departmental workflow, routine diagnosis and treatment of major diseases, specialized skills/procedures, and lifestyle guidance. Training materials and methods were tailored to the characteristics of each training module. Checklists were used for supervision and review, and a competency checklist was designed to evaluate residents' mastery of the training at two weeks of induction, which would guarantee the effectiveness of the training. A questionnaire survey, powered by wjx.cn, was used to obtain the experience and suggestions from the residents and ward instructors on induction education, and content ranking analysis was performed on the survey results.Results:The survey revealed that, before starting a new rotation, residents' top three educational needs were departmental workflow, routine diagnosis and treatment of common diseases, and specialized skills/procedures. Residents preferred face-to-face lectures and demonstrations by attending physicians or senior residents; instructors suggested improving relevant materials (such as resident physician manuals and video materials) and face-to-face lectures. The residents considered the current induction educational system to be greatly beneficial in basic theories, treatment principles, basic skills, and auxiliary examination processes.Conclusions:Through the above research, a multimodal induction educational system suitable for the standardized pediatric residency training base in the Peking University First Hospital has been preliminarily established, and suggestions for further improvement have been obtained, which is conducive to further improving the system and residents' post competency.
5.Application of biomimetic model combined with scenario simulation in otolaryngology skill training
Bo YU ; Hui KONG ; Rongnan ZHAO ; Yan GUO
Chinese Journal of Medical Education Research 2025;24(6):823-828
Objective:To study the application value of biomimetic model combined with scenario simulation in the training of otolaryngology skills.Methods:This study included 21 residents who underwent standardized residency training in the Department of Otolaryngology of the Second Hospital of Dalian Medical University from March to October 2023. The application of a teaching method combining biomimetic model and scenario simulation was evaluated by comparing pre- and post-training performance in terms of operation time, pass rate, and success rate. SPSS 23.0 was used for the paired sample t test and paired chi-square test. Results:Significant improvements were observed in several key indicators after training, including foreign body detection rate [(11/21) vs. (19/21)], number of assistance requests during using forceps [(1.62±0.92) vs. (0.90±0.94)], the number of touching the lateral pharyngeal wall [(4.62±0.92) vs. (1.90±1.34)], residual body incidence [(12/21) vs. (2/21)], operation time [(26.52±3.61) vs. (22.76±4.55)], and suture time [(19.10±2.98) vs. (15.24±1.18)]. Number of requests for tonsillectomy [(2.90 ± 1.04) vs. (0.86 ± 0.48)]( P<0.05). Conclusions:The combination of 3D biomimetic model with scenario simulation not only compensates for the limited practical training in otolaryngology and meets the requirements of clinical teaching, but also provides new ideas and methods for the reform of teaching otolaryngology. This approach is feasible for implementation in other training centers of similar scale.
6.Correlation between cerebral perfusion and cognitive function in patients with minor stroke or transient ischemic attack caused by severe intracranial arterial stenosis or occlusion
Meiling SHANG ; Yanran CHEN ; Bingbing GUO ; Xiaotong CHI ; Lu QUAN ; Gezhi YAN ; Hui WANG ; Ling MA ; Fude LIU ; Jia YU ; Jianfeng HAN ; Ming ZHANG ; Wanghuan DUN ; Yujing WANG
Chinese Journal of Cerebrovascular Diseases 2025;22(10):701-711
Objective This study aimed to investigate the correlation of cerebral perfusion and cognitive function status in patients with minor stroke(MS)or transient ischemic attack(TIA)complicated by severe intracranial arterial stenosis or occlusion(hereafter referred to as ICAS-MSTIA).Methods Retrospectively enrol consecutive ICAS-MSTIA patients admitted to the Department of Neurology,the First Affiliated Hospital of Xi'an Jiaotong University,from June 2023 to May 2024.In the meantime,healthy controls were openly recruited.The ICAS-MSTIA patients were divided into two groups based on the side of intracranial large artery stenosis or occlusion:the left intracranial large artery involvement group and the right intracranial large artery involvement group.All patients with intracranial large artery stenosis or occlusion underwent MR scanning within 2 weeks after the first episode of TIA or MS,while there was no specific time requirement for MR examination in the healthy control group.On the day of MR scanning,the Montreal cognitive assessment(MoCA)scale was used to evaluate the participants'global cognitive function and performance in various cognitive domains,including visuospatial/executive function,naming,attention,language,abstraction,delayed recall,and orientation.General information of all participants was collected,including age,sex,educational level,body mass index,and history of smoking and alcohol consumption.Clinical data were collected from both left and right intracranial large artery involvement groups,including cerebrovascular risk factors(such as,diabetes mellitus,hypertension,and hyperlipidemia),National Institutes of Health stroke scale(NIHSS)score at admission,responsible stenotic or occluded arteries(internal carotid artery,middle cerebral artery),degree of stenosis in the responsible vessel(severe stenosis[stenosis rate 70%-99%],occlusion[stenosis rate100%])and non-responsible vessel(no stenosis[0],mild stenosis[stenosis rate>0-49%]),collateral circulation compensation(American Society of Interventional and Therapeutic Neuroradiology/Society of Interventional Radiology[ASTIN/SIR]collateral circulation classification),and responsible events(TIA,MS).General data and MoCA scale scores were compared across the three groups,while clinical data were compared between the left and right intracranial large artery involvement groups.Statistical parametric mapping 12(SPM 12)was used to perform voxel-wise independent samples t-tests on cerebral blood flow(CBF)differences among the left ICAS-MSTIA group,right ICAS-MSTIA group,and healthy control group,with cluster-level family-wise error(FWE)correction applied for adjustment.Multiple linear regression analysis was conducted to evaluate the relationship between global CBF values and total MoCA scores in ICAS-MSTIA patients with left or right intracranial large artery involvement.Results A total of 33 ICAS-MSTIA patients and 33 healthy controls were enrolled in the study.Among the ICAS-MSTIA patients,21 had left intracranial large artery involvement and 12 had right involvement.(1)Among the three groups,statistically significant differences were observed in the proportions of individuals with reported smoking history(P=0.024)and alcohol consumption history(P=0.011).The left intracranial large artery involvement group had a higher NIHSS score(0[0,2]vs.0[0,0],P=0.044)and a higher proportion of patients with internal carotid artery involvement(13/21 cases vs.2/12 cases,P=0.027)compared with the right side group.No statistically significant differences were observed in other general or clinical data across the three groups or between the two non-control groups(all P>0.05).(2)Statistically significant differences were found across the three groups in the MoCA scale total score and scores of visuospatial/executive function,attention,language,abstraction,delayed recall,and orientation cognitive domains(all P<0.05),while no significant difference was noted in the naming score(P=0.063).The left intracranial large artery involvement group had lower total MoCA score and lower scores in visuospatial/executive function,attention,language,abstraction,delayed recall,and orientation in comparison to the healthy control group(all P<0.016 7).The right intracranial large artery involvement group had significantly lower scores in language,abstraction,and orientation domains than the healthy control group(all P<0.016 7).Additionally,the left side group had a lower attention domain score than the right side group(P<0.016 7).No other statistically significant differences were found in pairwise comparisons(all P>0.016 7).(3)Patients in both the left and right intracranial large artery involvement groups exhibited a significant decrease in CBF in extensive regions on the affected side,including the temporal lobe,dorsolateral prefrontal cortex,and occipital lobe.Furthermore,after correction,in the left involvement group CBF was higher in the contralateral lingual gyrus,cuneus,and calcarine sulcus compared with the healthy control group(P<0.05).While in the right involvement group,no regions had increased CBF compared to the healthy control group.(4)Multiple linear regression showed positive correlation between CBF in ipsilateral precentral gyrus and superior temporal gyrus,and the total MoCA score in patients with left intracranial large artery involvement(FWE-corrected,P<0.05).In contrast,there was no correlation between CBF and total MoCA score in patients with right intracranial large artery involvement.Conclusions ICAS-MSTIA patients exhibited various degrees of impairment in cerebral perfusion and cognitive function.A significant positive correlation is observed between these two impairments in patients with left intracranial large artery involvement.
7.Preliminary study on the role and mechanism of ISG15 in exosomes in platinum resistance in ovarian cancer
Yanan TIAN ; Hui ZHENG ; Tianqing YAN ; Heng ZHANG ; Renquan LU ; Lin GUO
China Oncology 2025;35(4):346-354
Background and purpose:Epithelial ovarian cancer(EOC)has a poor prognosis and is prone to developing resistance to platinum-based chemotherapy.Exosomes are currently believed to be involved in platinum resistance in ovarian cancer.This study explored the role and mechanism of exosomes on platinum resistance of ovarian cancer.Methods:Through ultracentrifugation,exosomes were isolated and analyzed using electron microscopy,particle size studies,and Western blot for detailed exosome analysis.We detected the expression levels of exosomal proteins and related signaling pathways.Exosomal protein expression profile was analyzed by proteomics.Key differential proteins were screened by intersecting with existing drug resistance datasets.Furthermore,patients diagnosed with EOC via pathological analysis at the Fudan University Shanghai Cancer Center from August 2023 to August 2024,who underwent surgery and fulfilled the eligibility requirements,were gathered to examine the link between the expression of interferon-stimulated gene 15(ISG15)in serum exosomes and resistance to platinum medication.The expression levels of related proteins in serum exosomes were quantitatively detected by enzyme-linked immunosorbent assay(ELISA).Receiver operating characteristic(ROC)curve was plotted to explore the predictive value of serum exosomal protein in ovarian cancer resistance.Results:Exosomes derived from platinum-sensitive and drug-resistant ovarian cancer cells were extracted and proteomic analysis was further performed.We identified 9 differential proteins associated with platinum-resistance and found the key molecule interferon-stimulated gene 15(ISG15).Compared with sensitive cells,the expression of ISG15 in exosomes of drug-resistant ovarian cancer cells was significantly upregulated.Exosome tracer tests showed that exosomes were successfully taken up by ovarian cancer receptor cells.After coculture with drug-resistant exosomes,the expression level of ISG15 in ovarian cancer receptor cells was increased.Knockdown ISG15 in EOC cells decreased the expression of ISG15 in exosomes,and incubation of ISG15-knockdown exosomes decreased the cell viability on the condition of platinum drugs,indicating that ISG15 in exosomes regulated platinum resistance of ovarian cancer cells.Moreover,ISG15 could regulate the expression of multidrug resistance protein 1(MDR1)through phosphoinositide 3-kinase(PI3K)/protein kinase B(AKT)/nuclear factor-kappa-light-chain-enchancer of activated B cells(NF-κB)signaling pathway.This study included a total of 87 patients.Clinical serum samples also showed that the expression of ISG15 in exosomes was higher in platinum-resistant ovarian cancer patients than in sensitive ovarian cancer patients.Using serum exosomal ISG15 as an indicator to distinguish between sensitivity and resistance,the area under ROC curve was 0.779(P<0.05),cutoffvalue was 27.35ng/mL,sensitivity was 70.2%,and specificity was 76.4%.Conclusion:ISG15 in exosomes can regulate the expression of MDR1 in ovarian cancer cells through PI3K/AKT/NF-κB signaling pathway,and promote platinum resistance in ovarian cancer cells.
8.Expert consensus on infection prevention and control of Creutzfeldt-Jakob disease in medical institutions
Tianxiang GE ; Yangyang JIA ; Chunhui LI ; Jianrong HUANG ; Xiujuan MENG ; Xiaodong GAO ; Jingping ZHANG ; Fu QIAO ; Lijuan XIONG ; Hui LIANG ; Wei LI ; Haiyan LOU ; Wenjuan WU ; Tianxin XIANG ; Jiansen CHEN ; Biao ZHU ; Kaijin XU ; Zhihui ZHOU ; Hongliu CAI ; Meihong YU ; Yan ZHANG ; Yanwan SHANGGUAN ; Haiting FENG ; Hangping YAO ; Lei GUO ; Tieer GAN ; Weihong ZHANG ; Jimin SUN ; Ye LU ; Qun LU ; Meng CAI ; Jin SHEN ; Yunsong YU ; Anhua WU ; Liu-yi LI ; Tingting QU
Chinese Journal of Infection Control 2025;24(4):437-450
Creutzfeldt-Jakob disease(CJD)is a rapidly progressive and fatal neurodegenerative disorder caused by prions,with certain infectivity and iatrogenic transmission risks.With the rapid progress and application of new dia-gnostic biomarkers and detection methods,as well as the construction and improvement of surveillance and reporting systems,the detection of CJD in patients domestically and internationally has shown an increasing trend year by year.Due to its long incubation period and heterogeneity of early symptoms,early identification and diagnosis of the disease is difficult,increasing the risk of transmission within medical institutions.Currently,there is a lack of con-sensus on the infection prevention and control of CJD.In order to timely identify and diagnose CJD as well as effec-tively block its transmission in medical institutions,this consensus summarizes 15 clinical concerns and formulates 24 specific recommendations based on the latest domestic and international research findings and clinical evidence,as well as combines with clinical practice,aiming to standardize healthcare-associated infection prevention and control measures for CJD and reduce its transmission risk in medical institutions.
9.Proficiency testing for 11 clinical biobanks in Beijing City: simulation study and result analysis
Qian ZHANG ; Yun ZHANG ; Lu HAN ; Min LIU ; Yongbo YU ; Yan WANG ; Ying HU ; Hui ZHONG ; Dan GUO ; Shipeng SUN ; Jinxi LIN ; Siyuan XU ; Xiaokun TANG ; Gaoyuan SUN ; Chuanbao ZHANG ; Hexin LI
Chinese Journal of Preventive Medicine 2025;59(9):1590-1596
Objective:To evaluate the sample preparation proficiency and storage proficiency of 11 clinical biobanks in Beijing through simulated experiments, and to establish an assessment method for the quality comparability of biological samples.Methods:An exploratory research design was adopted. In November 2023, artificial composite serum quality control materials containing six recombinant human protein markers—recombinant human alanine aminotransferase (rhALT), recombinant human aspartate aminotransferase (rhAST), recombinant human creatine kinase (rhCK), recombinant human creatine kinase-MB (rhCK-MB), recombinant human B-type natriuretic peptide (rhBNP), and recombinant human troponin I (rhTNI)—were distributed to 11 clinical biobanks in Beijing City. Sample preparation and storage followed the standardized operating procedures. Proficiency differences were assessed through statistical analysis.Results:Three-way repeated measures ANOVA revealed all six protein markers showed a declining trend over storage time in ultra-low-temperature environments ( F values 11.68-4 179.66, all P<0.01). However, neither long-term/temporary refrigerator types ( F values 0.01-1.23, all P>0.05)nor placement locations within refrigerators significantly affected the stability of these six proteins ( F valus 0.03-1.47, all P>0.05). The biases in detection results for rhALT, rhAST, rhTNI, and rhBNP at different storage time points were within the allowable bias limits for each item, supporting their use as markers for protein stability in biobank samples. All 11 institutions passed the storage proficiency assessment. In the preparation proficiency assessment, deviations were observed in post-preparation sample results, with a notably high out-of-control rate for rhCK (36.36%). Conclusion:Sample preparation proficiency can serve as a quality control metric for clinical biobanks. Future external quality assessment systems for biobanks should focus on sample preparation rather than storage processes.
10.Epidemiological trends and resistance mechanisms of enterobacterales carrying multiple carbapenemases
Ke WANG ; Qi WANG ; Shuo YANG ; Ruiqi WANG ; Xujun CAI ; Jun HOU ; Hong ZOU ; Yan JIN ; Mei LI ; Hui GUO ; Liang JIN ; Xu YANG ; Lin ZHANG ; Hui WANG
Chinese Journal of Laboratory Medicine 2025;48(9):1158-1164
Objective:To characterize the epidemiology, antimicrobial susceptibility, and molecular mechanisms of carbapenem-resistant Enterobacterales (CRE) carrying multiple carbapenemase genes in China, and to provide evidence for infection control and antibiotic stewardship.Methods:From 2016 to 2023, 115 CRE isolates harboring at least two carbapenemase genes were collected from 41 hospitals in 18 provinces across China. Species identification, antimicrobial susceptibility testing, and whole-genome sequencing were performed. Multilocus sequence typing (MLST) and capsular typing were conducted using Kleborate, plasmid replicon types were identified with PlasmidFinder, and a core genome phylogenetic tree was constructed.Results:The majority of isolates belonged to Klebsiella spp. (80.0%, 92/115), followed by E. cloacae (8.7%, 10/115) and E. coli (6.1%, 7/115). The isolates were mainly from Hebei, Beijing, Shandong, and Hunan (60.9%, 70/115), and sputum was the predominant specimen (43.5%, 50/115). The most common genotype was bla KPC+bla NDM (73.0%, 84/115), primarily in Klebsiella spp. (79.8%, 67/84), followed by bla NDM+bla IMP (15.7%, 18/115). The prevalent plasmid replicon types were IncFII (77.5%, 86/111), IncFIB (68.5%, 76/111), IncR (51.4%, 57/111), and IncX3 (20.7%, 23/111). Notably, 88.6% (31/35) of ST11-KL64 K. pneumoniae strains co-harbored IncFII, IncFIB, and IncR plasmids simultaneously. Between 2016 and 2022, the dominant subtype among Klebsiella spp. isolates was bla KPC-2+bla NDM-1 (56.2%, 36/64). In 2023, the bla KPC-2+bla NDM-13 subtype (29.5%, 19/64) emerged and exhibited clonal transmission (single nucleotide polymorphism 2?74 bp) in Hebei, Beijing, and Jilin. Susceptibility testing showed widespread resistance to β-lactams (90.2%-100%). Aztreonam-avibactam, tigecycline, and colistin retained high activity, with susceptibility rates of 90.16%-98.36%. Conclusions:In China, the majority of clinical Enterobacteriaceae strains that harbor multiple carbapenemases are Klebsiella spp. co-producing KPC and NDM enzymes. Dissemination is driven by both clonal expansion of ST11-KL64 and horizontal transfer of IncFII, IncFIB, and IncR plasmids. The recent emergence and regional clonal spread of the bla KPC-2+bla NDM-13 genotype underscore the urgent need for strengthened surveillance and containment measures.


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