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.Effect of galvanic vestibular stimulation on stroke patients with lateropulsion
Xiang GONG ; Menghuan WANG ; Cunshu WU ; Junwen CHEN ; Yue XIAO ; Yun YANG ; Wanting SUN ; Jun LU ; Guangxu XU
Chinese Journal of Rehabilitation Theory and Practice 2024;30(2):210-216
ObjectiveTo investigate the effect of galvanic vestibular stimulation on stroke patients with lateropulsion. MethodsFrom February to October, 2023, 30 stroke patients with lateropulsion in the First Affiliated Hospital of Nanjing Medical University were divided into control group (n = 15) and experimental group (n = 15) randomly. The control group received routine rehabilitation and sham galvanic vestibular stimulation, and the experimental group received routine rehabilitation and true galvanic vestibular stimulation, for two weeks. They were assessed with Scale for Contraversive Pushing (SCP), subjective visual vertical (SVV), Line Cancellation Test (LCT), Star Cancellation Test (SCT), Berg Balance Scale (BBS), Holden Functional Ambulation Category (FAC) and Barthel Index (BI) before and after treatment. ResultsAll the indexes improved in both groups after intervention (|t| > 2.461, Z > 3.000, P < 0.05), except the SVV orientation, SVV certainty and SCT in the control group; while the SCP, SVV certainty, LCT and FAC were better in the experimental group than in the control group (|t| > 2.189, Z = -2.862, P < 0.05), and the differences before and after intervention were better in the experimental group than in the control group (|t| > 2.382, P < 0.05), except LCT. SCP was correlated with SVV orientation, SVV certainty, SCT, BBS, BI and FAC (|r| > 0.381, P < 0.05). ConclusionGalvanic vestibular stimulation can improve the lateropulsion, balance, walking function and activities of daily living in stroke patients, which may be related to improvement for spatial cognitive function, especially vertical perception.
3.Analysis of fertility preservation and HPV negative conversion rate of LEEP by separating the vesicorectal space
Ting JIANG ; Yu XIE ; Ying-Xin GONG ; Yun-Qiang ZHANG ; Yue SHI ; Ruo-Yi GUO ; Qing WANG ; Xiao-Xia LIU
Fudan University Journal of Medical Sciences 2024;51(2):211-217
Objective To explore the eradication rate of human papillomavirus(HPV)and gestational outcome of patients with high-grade squamous intraepithelial disease of the cervix(HSIL)after loop electrosurgical excision procedure(LEEP)by transvaginal dissection of the vesicorectal form the cervix.Methods A total of 53 patients treated with LEEP by transvaginal dissection of the vesicorectal form the cervix in Obstetrics and Gynecology Hospital,Fudan University from Jan to Dec,2019 were investigated.Clinical information of cervical cytological examination,HPV test and cervical biopsy under colposcopy were followed up for 6,12 and 24 months post-LEEP were collected.HPV infection in these 53 patients were compared before and after LEEP surgery.The rate of successful fertility of the cohort,the HPV conversion rate of patients with hysterectomy and LEEP done were compared.The association between the pathological type and positive surgical margin and the association between HPV infection type and positive surgical margin were analyzed.Results HPV infection rate of was 94.3%(50/53)and the proportion of HPV16 and/or 18 infection was 75.5%(40/53).Mono-HPV infection rate(69.8%,37/53)was significantly higher than mixed HPV infection rate(22.7%,13/53).Thirty-eight patients(71.7%)were found with positive surgical margin in previous LEEP operation.Fifteen patients had recurrence(28.3%)and 40 patients(75.5%)successfully delivered baby after surgery.Postoperative pathology was mainly HSIL,accounting for 66%(30/53),and 28.3%patients(15/53)had no pathological change.Forty cases had satisfying fertility-conservative operation outcome with negative surgical margin,and 38 patients eradicated HPV infection after LEEP,which took up 95%of patients with satisfying fertility-conservative operation.There was no significant difference of positive resection margin rate in between groups of HPV16/18 infection and other types.Five cases had successful delivery(12.5%,5/40)with 1 case of vaginal delivery and 4 cases of cesarean section.Among these 5 cases,3 cases undertook preventive cervical cerclage,with 1 case of vaginal delivery and 2 cases of cesarean sections.Conclusion HPV eradication rate and surgical outcome could be significantly improved by LEEP with transvaginal dissection of the vesicorectal from the cervix,which satisfied the fertility preservation of females at reproductive age.
4.Long-term outcome of patients with rectal cancer who achieve complete or near complete clinical responses after neoadjuvant therapy: a multicenter registry study of data from the Chinese Watch and Wait Database
Yiming ZHAO ; Weihu WANG ; Wei ZHANG ; Lin WANG ; Shuai LI ; Jingwen WANG ; Leen LIAO ; Guanyu YU ; Zhen SUN ; Yanli QU ; Yang GONG ; Yun LU ; Tao WU ; Yunfeng LI ; Quan WANG ; Guohua ZHAO ; Yi XIAO ; Peirong DING ; Zhen ZHANG ; Aiwen WU
Chinese Journal of Gastrointestinal Surgery 2024;27(4):372-382
Objective:To report the long-term outcomes of Chinese rectal cancer patients after adopting a Watch and Wait (W&W) strategy following neoadjuvant therapy (NAT).Methods:This multicenter, cross-sectional study was based on real-world data. The study cohort comprised rectal cancer patients who had achieved complete or near complete clinical responses (cCRs, near-cCRs) after NAT and were thereafter managed by a W&W approach, as well as a few patients who had achieved good responses after NAT and had then undergone local excision for confirmation of pathological complete response. All participants had been followed up for ≥2 years. Patients with distant metastases at baseline or who opted for observation while living with the tumor were excluded. Data of eligible patients were retrospectively collected from the Chinese Wait-and-Watch Data Collaboration Group database. These included baseline characteristics, type of NAT, pre-treatment imaging results, evaluation of post-NAT efficacy, salvage measures, and treatment outcomes. We herein report the long-term outcomes of Chinese rectal cancer patients after NAT and W&W and the differences between the cCR and near-cCR groups.Results:Clinical data of 318 rectal cancer patients who had undergone W&W for over 2 years and been followed up were collected from eight medical centers (Peking University Cancer Hospital, Fudan University Shanghai Cancer Center, Sun Yat-sen University Cancer Center, Shanghai Changhai Hospital, Peking Union Medical College Hospital, Liaoning Cancer Hospital, the First Hospital of Jilin University, and Yunnan Cancer Hospital.) The participants comprised 221 men (69.4%) and 107 women (30.6%) of median age 60 (26-86) years. The median distance between tumor and anal verge was 3.4 (0-10.4) cm. Of these patients, 291 and 27 had achieved cCR or near-cCR, respectively, after NAT. The median duration of follow-up was 48.4 (10.2-110.3) months. The 5-year cumulative overall survival rate was 92.4% (95%CI: 86.8%-95.7%), 5-year cumulative disease-specific survival (CSS) rate 96.6% (95%CI: 92.2%-98.5%), 5-year cumulative organ-preserving disease-free survival rate 86.6% (95%CI: 81.0%-90.7%), and 5-year organ preservation rate 85.3% (95%CI: 80.3%-89.1%). The overall 5-year local recurrence and distant metastasis rates were 18.5% (95%CI: 14.9%-20.8%) and 8.2% (95%CI: 5.4%-12.5%), respectively. Most local recurrences (82.1%, 46/56) occurred within 2 years, and 91.0% (51/56) occurred within 3 years, the median time to recurrence being 11.7 (2.5-66.6) months. Most (91.1%, 51/56) local recurrences occurred within the intestinal lumen. Distant metastases developed in 23 patients; 60.9% (14/23) occurred within 2 years and 73.9% (17/23) within 3 years, the median time to distant metastasis being 21.9 (2.6-90.3) months. Common sites included lung (15/23, 65.2%), liver (6/23, 26.1%), and bone (7/23, 30.4%) The metastases involved single organs in 17 patients and multiple organs in six. There were no significant differences in overall, cumulative disease-specific, or organ-preserving disease-free survival or rate of metastases between the two groups (all P>0.05). The 5-year local recurrence rate was higher in the near-cCR than in the cCR group (41.6% vs. 16.4%, P<0.01), with a lower organ preservation rate (69.2% vs. 88.0%, P<0.001). The success rates of salvage after local recurrence and distant metastasis were 82.1% (46/56) and 13.0% (3/23), respectively. Conclusion:Rectal cancer patients who achieve cCR or near-cCR after NAT and undergo W&W have favorable oncological outcomes and a high rate of organ preservation. Local recurrence and distant metastasis during W&W follow certain patterns, with a relatively high salvage rate for local recurrence. Our findings highlight the importance of close follow-up and timely intervention during the W&W process.
5.Preliminary study on delaying aging induced thymus degeneration in SAMP6 mice with Bazi Bushen capsule
Zhao-Dong LI ; Yin-Xiao CHEN ; Bo-Yang GONG ; Zhe XU ; Zhi-Xian YU ; Yue-Xuan SHI ; Yan-Fei PENG ; Yu-Hong BIAN ; Yun-Long HOU ; Xiang-Ling WANG ; Shu-Wu ZHAO
Chinese Pharmacological Bulletin 2024;40(6):1186-1192
Aim To explore the improvement effect of Bazi Bushen capsule on thymic degeneration in SAMP6 mice and the possible mechanism.Methods Twenty 12 week old male SAMP6 mice were randomly divided into the model group(SAMP6)and the Bazi Busheng capsule treatment group(SAMP6+BZBS).Ten SAMR1 mice were assigned to a homologous control group(SAMR1).The SAMP6+BZBS group was oral-ly administered Bazi Bushen capsule suspension(2.8 g·kg-1)daily,while the other two groups were orally administered an equal amount of distilled water.After nine weeks of administration,the morphology of the thymus in each group was observed and the thymus in-dex was calculated;HE staining was used to observe the structural changes of thymus tissue;SA-β-gal stai-ning was used to detect thymic aging;flow cytometry was used to detect the proportion of thymic CD3+T cells in each group;Western blot was used to detect the levels of p16,Bax,Bcl-2,and cleaved caspase-3 proteins in thymus;immunofluorescence was applied to detect the proportion of cortical thymic epithelial cells in each group;ELISA was employed to detect IL-7 lev-els in thymus.Results Compared with the SAMP6 group,the thymic index of the SAMP6+BZBS group significantly increased(P<0.05);the disordered thy-mic structure was significantly improved;the positive proportion of SA-β-gal staining significantly decreased(P<0.01);the proportion of CD3+T cells apparently increased(P<0.05);the level of p16 protein signifi-cantly decreased(P<0.05);the level of Bcl-2 pro-tein significantly increased(P<0.05),while the lev-el of cleaved caspase-3 protein markedly decreased(P<0.05);the proportion of cortical thymic epithelial cells evidently increased;the level of IL-7 significantly increased(P<0.01).Conclusions Bazi Bushen capsule can delay thymic degeneration,inhibit cell ap-optosis in thymus and promote thymic cell development in SAMP6 mice,which may be related to increasing the proportion of cortical thymic epithelial cells and promoting IL-7 secretion.
6.Effects of alone and co-administration of berberine and 5'-N-ethylformamidoadenosine on cardiomyocyte hypoxia/reoxygen injury
Mei-Na GONG ; Ya-Yun GAO ; Shu-Ying ZHANG ; Xiao-Qian PANG ; Wei TIAN ; Jing-Man XU
Chinese Pharmacological Bulletin 2024;40(12):2311-2318
Aim To investigate the effects of berberine(BBR)combined with 5'-n-ethylformamidoadenosine(NECA)on myocardial H9c2 and HL-1 cell damage induced by hypoxia/reoxygenation(H/R).Methods H9c2 and HL-1 cells were divided into the Control group,BBR group,NECA group,combined administra-tion group,H/R group,BBR+H/R group,NECA+H/R group,and combined administration+H/R group.CCK-8 was used to detect cell viability in each group.The TMRE kit was used to detect MMP.DCFH-DA was used to detect ROS content.The Mito SOX Red fluorescent probe was used to detect mitochondrial su-peroxide.The expressions of COX Ⅳ,Tom20,and Tim23 were detected by Western blot.The expression of COX Ⅳ and Tom20 genes was detected by qRT-PCR.Results In H9c2 cells,the cell viability and TMRE fluorescence intensity in the H/R group were significantly decreased compared with the Control group.The protein expressions of COX Ⅳ,Tom20,and Tim23,gene expressions of COX Ⅳ and Tom20,ROS,and mitochondrial superoxide contents were significant-ly increased.Compared with the H/R group,the cell viability of BBR and NECA were enhanced after ad-ministration alone.The contents of ROS and mitochon-drial superoxide were significantly decreased.In HL-1 cells,cell viability in the H/R group was significantly decreased compared with the Control group.The con-tents of ROS and mitochondrial superoxide were signifi-cantly increased.Compared with the H/R group,BBR and NECA alone and combined administration en-hanced cell viability.The contents of ROS and mito-chondrial superoxide were significantly decreased.Conclusion The administration of BBR and NECA a-lone or in combination can reduce the production of mi-tochondrial superoxide and cell ROS,thereby allevia-ting mitochondrial damage,alleviating oxidative stress damage,and ultimately reducing H/R-induced myocar-dial cell damage.
7.A novel nomogram-based model to predict the postoperative overall survival in patients with gastric and colorectal cancer
Siwen WANG ; Kangjing XU ; Xuejin GAO ; Tingting GAO ; Guangming SUN ; Yaqin XIAO ; Haoyang WANG ; Chenghao ZENG ; Deshuai SONG ; Yupeng ZHANG ; Lingli HUANG ; Bo LIAN ; Jianjiao CHEN ; Dong GUO ; Zhenyi JIA ; Yong WANG ; Fangyou GONG ; Junde ZHOU ; Zhigang XUE ; Zhida CHEN ; Gang LI ; Mengbin LI ; Wei ZHAO ; Yanbing ZHOU ; Huanlong QIN ; Xiaoting WU ; Kunhua WANG ; Qiang CHI ; Jianchun YU ; Yun TANG ; Guoli LI ; Li ZHANG ; Xinying WANG
Chinese Journal of Clinical Nutrition 2024;32(3):138-149
Objective:We aimed to develop a novel visualized model based on nomogram to predict postoperative overall survival.Methods:This was a multicenter, retrospective, observational cohort study, including participants with histologically confirmed gastric and colorectal cancer who underwent radical surgery from 11 medical centers in China from August 1, 2015 to June 30, 2018. Baseline characteristics, histopathological data and nutritional status, as assessed using Nutrition Risk Screening 2002 (NRS 2002) score and the scored Patient-Generated Subjective Global Assessment, were collected. The least absolute shrinkage and selection operator regression and Cox regression were used to identify variables to be included in the predictive model. Internal and external validations were performed.Results:There were 681 and 127 patients in the training and validation cohorts, respectively. A total of 188 deaths were observed over a median follow-up period of 59 (range: 58 to 60) months. Two independent predictors of NRS 2002 and Tumor-Node-Metastasis (TNM) stage were identified and incorporated into the prediction nomogram model together with the factor of age. The model's concordance index for 1-, 3- and 5-year overall survival was 0.696, 0.724, and 0.738 in the training cohort and 0.801, 0.812, and 0.793 in the validation cohort, respectively.Conclusions:In this study, a new nomogram prediction model based on NRS 2002 score was developed and validated for predicting the overall postoperative survival of patients with gastric colorectal cancer. This model has good differentiation, calibration and clinical practicability in predicting the long-term survival rate of patients with gastrointestinal cancer after radical surgery.
8.Effects of morphine pretreatment on mitochondrial dynamics change induced by hypoxia/reoxygenation in myocardial cells
Ya-Yun GAO ; Yun-Qi WANG ; Xi ZHANG ; Mei-Na GONG ; Xiao-Qian PANG ; Wei TIAN ; Jing-Man XU
The Chinese Journal of Clinical Pharmacology 2024;40(14):2023-2027
Objective The aim of the study was to investigate how morphine(Mor)effects mitochondrial dynamics change of H9c2 induced by hypoxia/reoxygenation(H/R).Methods Myocardial H9c2 cells were divided into blank group(without treatment),model group(H/R treatment),control group(5 μmol·L-1 Mor treatment)and experimental group(H/R+5 μmol·L-1 Mor treatment).The content of reactive oxygen species(ROS),mitochondrial membrane potential(MMP),and complex of Ⅰ and Ⅲ activity were detected using ROS,tetramethylrhodamine ethyl ester(TMRE),and mitochondrial complex of Ⅰ and Ⅲ activity detection kits,respectively.The morphology of mitochondria and lysosomes was observed by transmission electron microscope electron microscopy(TEM);Western blot was used to detect the expression of GTPase kinetic protein 1(Drp1),cytochrome c oxidase Ⅳ(COX Ⅳ)and transporters of the outer mitochondrial membrane(TOM20).Results The nuclear membrane was smooth and complete;the mitochondrial size was consistent;the crest arrangement was neat;vacuolization was reduced or even disappeared;the mitochondrial matrix electron density was increased;the number of autophagosomes was decreased in the experimental group.The contents of ROS in blank group,model group,control group and experimental group were 1.03±0.04,1.53±0.10,1.06±0.06 and 1.10±0.11;MMP were 1.00±0.15,0.80±0.16,1.06±0.19 and 1.00±0.19;the activities of complex of Ⅰ were 1.00±0.08,2.28±0.82,1.05±0.26 and 1.13±0.37;the activities of complex of Ⅲ were 1.00±0.09,2.13±0.38,0.83±0.22 and 0.96±0.11;the expression of Drp1 protein were 1.00±0.14,1.27±0.07,0.97±0.21 and 0.93±0.17;the expression of fission protein 1(Fis1)protein were 1.00±0.16,1.33±0.18,1.17±0.25 and 0.99±0.05;the expression of COX Ⅳ protein were 1.00±0.25,0.62±0.08,0.79±0.26 and 0.97±0.16;the expression of TOM20 protein were 1.00±0.13,0.67±0.15,0.75±0.13 and 0.89±0.05.The above indexes of model group were significantly different from those of blank group(P<0.05,P<0.01,P<0.001,P<0.000 1).The above indexes of experimental group were significantly different from those of model group(P<0.05,P<0.01,P<0.001,P<0.000 1).Conclusion Morphine may inhibit mitophagy and fission,and alleviated mitochondrial oxidative stress damage by decreasing the activity of respiratory chain complex of Ⅰ and Ⅲ,thus maintaining mitochondrial dynamic homeostasis and alleviating H/R-induced myocardial cell damage.
9.Long-term outcome of patients with rectal cancer who achieve complete or near complete clinical responses after neoadjuvant therapy: a multicenter registry study of data from the Chinese Watch and Wait Database
Yiming ZHAO ; Weihu WANG ; Wei ZHANG ; Lin WANG ; Shuai LI ; Jingwen WANG ; Leen LIAO ; Guanyu YU ; Zhen SUN ; Yanli QU ; Yang GONG ; Yun LU ; Tao WU ; Yunfeng LI ; Quan WANG ; Guohua ZHAO ; Yi XIAO ; Peirong DING ; Zhen ZHANG ; Aiwen WU
Chinese Journal of Gastrointestinal Surgery 2024;27(4):372-382
Objective:To report the long-term outcomes of Chinese rectal cancer patients after adopting a Watch and Wait (W&W) strategy following neoadjuvant therapy (NAT).Methods:This multicenter, cross-sectional study was based on real-world data. The study cohort comprised rectal cancer patients who had achieved complete or near complete clinical responses (cCRs, near-cCRs) after NAT and were thereafter managed by a W&W approach, as well as a few patients who had achieved good responses after NAT and had then undergone local excision for confirmation of pathological complete response. All participants had been followed up for ≥2 years. Patients with distant metastases at baseline or who opted for observation while living with the tumor were excluded. Data of eligible patients were retrospectively collected from the Chinese Wait-and-Watch Data Collaboration Group database. These included baseline characteristics, type of NAT, pre-treatment imaging results, evaluation of post-NAT efficacy, salvage measures, and treatment outcomes. We herein report the long-term outcomes of Chinese rectal cancer patients after NAT and W&W and the differences between the cCR and near-cCR groups.Results:Clinical data of 318 rectal cancer patients who had undergone W&W for over 2 years and been followed up were collected from eight medical centers (Peking University Cancer Hospital, Fudan University Shanghai Cancer Center, Sun Yat-sen University Cancer Center, Shanghai Changhai Hospital, Peking Union Medical College Hospital, Liaoning Cancer Hospital, the First Hospital of Jilin University, and Yunnan Cancer Hospital.) The participants comprised 221 men (69.4%) and 107 women (30.6%) of median age 60 (26-86) years. The median distance between tumor and anal verge was 3.4 (0-10.4) cm. Of these patients, 291 and 27 had achieved cCR or near-cCR, respectively, after NAT. The median duration of follow-up was 48.4 (10.2-110.3) months. The 5-year cumulative overall survival rate was 92.4% (95%CI: 86.8%-95.7%), 5-year cumulative disease-specific survival (CSS) rate 96.6% (95%CI: 92.2%-98.5%), 5-year cumulative organ-preserving disease-free survival rate 86.6% (95%CI: 81.0%-90.7%), and 5-year organ preservation rate 85.3% (95%CI: 80.3%-89.1%). The overall 5-year local recurrence and distant metastasis rates were 18.5% (95%CI: 14.9%-20.8%) and 8.2% (95%CI: 5.4%-12.5%), respectively. Most local recurrences (82.1%, 46/56) occurred within 2 years, and 91.0% (51/56) occurred within 3 years, the median time to recurrence being 11.7 (2.5-66.6) months. Most (91.1%, 51/56) local recurrences occurred within the intestinal lumen. Distant metastases developed in 23 patients; 60.9% (14/23) occurred within 2 years and 73.9% (17/23) within 3 years, the median time to distant metastasis being 21.9 (2.6-90.3) months. Common sites included lung (15/23, 65.2%), liver (6/23, 26.1%), and bone (7/23, 30.4%) The metastases involved single organs in 17 patients and multiple organs in six. There were no significant differences in overall, cumulative disease-specific, or organ-preserving disease-free survival or rate of metastases between the two groups (all P>0.05). The 5-year local recurrence rate was higher in the near-cCR than in the cCR group (41.6% vs. 16.4%, P<0.01), with a lower organ preservation rate (69.2% vs. 88.0%, P<0.001). The success rates of salvage after local recurrence and distant metastasis were 82.1% (46/56) and 13.0% (3/23), respectively. Conclusion:Rectal cancer patients who achieve cCR or near-cCR after NAT and undergo W&W have favorable oncological outcomes and a high rate of organ preservation. Local recurrence and distant metastasis during W&W follow certain patterns, with a relatively high salvage rate for local recurrence. Our findings highlight the importance of close follow-up and timely intervention during the W&W process.
10.Drug resistance and molecular typing of diarrheagenic escherichia coli from the diarrhea clinics in Qingpu District, Shanghai.
Yi Ru SHI ; Xi YU ; Yi HU ; Shu Wen MA ; Xiao Yun LU ; Xi GONG ; Qiu Fang XU
Chinese Journal of Preventive Medicine 2023;57():65-71
Objective: To analyze the drug resistance and multilocus sequence typing of five types of diarrheagenic Escherichia coli (DEC) isolated from diarrhea outpatients of diarrhea comprehensive monitoring designated hospital in Qingpu District, Shanghai from 2015 to 2019. Methods: From January 2015 to December 2019, five types of DEC, isolated and identified from diarrhea outpatient cases' anal swabs of the Qingpu branch of Zhongshan Hospital were collected to determine the minimal inhibitory concentration by using the micro broth dilution susceptibility test. The strains, resistant to the third-generation cephalosporins or carbapenems, or producing ESBLs, were selected based on the results of sensitivity tests and determined by WGS. The MLST typing of DEC was analyzed based on the WGS technology and the minimum spanning tree was constructed by BioNumerics 7.6 software to analyze the local dominant flora. Results: A total of 513 strains of DEC were detected and isolated from 4 494 anal swabs, with a detection rate of 11.42%. About 500 strains were tested for drug sensitivity to nine antibiotics in four classes, including 330 strains of enterotoxigenic E.coli (ETEC), 72 strains of enteroaggregative E.coli (EAEC), 95 strains of enteropathogenic E.coli (EPEC), 1 strain of enterohemorrhagic E.coli (EHEC), and 2 strains of enteroinvasive E.coli (EIEC). From 2015 to 2019, the resistance rate of cefotaxime-clavulanic acid was significantly different (P<0.05). The resistance rate of virulence types of DEC to nalixic acid was significantly different (P<0.05). About 71 strains of DEC were determined by WGS, and 77 drug-resistant genes were detected. Strains were classified into 32 ST subtypes, with the dominant genotypes being ST-1491 (29.6%, 21/71) and ST-10 Complex (23.9%, 17/71). All ST-1491 produced ESBLs, which were blaCTX-M gene mutant strains. The dominant type of ST-10 complex was ST-218 (35.3%, 6/17). In addition, 8 strains of EAEC, 14 strains of EPEC and 49 strains of ETEC were classified into 7, 14 and 18 ST subtypes, respectively. Conclusion: The drug resistance of DEC strains from the diarrhea outpatient case of Qingpu District is serious. The ST types of EAEC and EPEC are highly polymorphic. The dominant ST types of DEC are basically consistent with the common genotypes in southeast China.

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