ObjectiveThis paper aims to observe the syndrome improvement and negative antigen conversion rate of Qingxuan Daozhi formula in the treatment of influenza in children （heat accumulation in the lung and stomach syndrome）. MethodsThrough a multi-center randomized controlled methodology design，confirmed influenza cases were collected from October 2022 to April 2023 in the pediatrics department of eight hospitals，such as Dongfang Hospital of Beijing University of Chinese Medicine. A total of 180 children with influenza and heat accumulation in the lung and stomach syndrome conforming to the standard were recruited through the clinic. The sick children meeting the inclusion criteria were randomly divided into groups by a block-randomized method. The children in the experimental group were treated with Qingxuan Daozhi formula for five days，and those in the control group were treated with Oseltamivir Phosphate Granules for five days. The primary efficacy indicator was the negative conversion rate of influenza antigen detection. Secondary efficacy indicators were the Canadian acute respiratory illness and flu scale （CARIFS） and the incidence of complications，severe cases， and critical cases. Follow-up observation was conducted on the day of enrollment，48 hours after medication，72 hours after medication， and （6+1） d after medication. ResultsOne hundred and eighty participants were randomly assigned to the experimental group （90 cases） or the control group （90 cases）. All participants were followed up during the study. Comparison of influenza antigen detection results in the primary efficacy indicators showed that the average time of negative influenza antigen conversion in the experimental group was （5.29±1.25） d，and that in the control group was （5.40±1.68） d，without a statistically significant difference. After five days of intervention，52 cases in the experimental group and 51 cases in the control group converted to negative，without a statistically significant difference. CARIFS score results in the secondary efficacy indicators showed that during 72 hours after intervention，there were statistically significant differences between the experimental group and the control group in three dimensions， including headache，muscle soreness， and the need for extra care （P<0.05）. On the （6+1） days after the intervention，the differences in both the experimental group and the control group were statistically significant in 10 dimensions， including sore throat，bad sleep，uncomfortable feeling，poor spirit and fatigue，crying more than usual，the need for extra care，symptom，function，influence on parents，and total score （P<0.05）. The comparison results within the group in the dimensional scores of symptom， function， and influence on parents，as well as the CARIFS total score showed that with the delay of follow-up time，scores of both groups decreased significantly，with a statistically significant difference （P<0.01）. Inter-group comparison results showed that the mean score of the experimental group was higher than that of the control group at the time of enrollment. With the progress of intervention，the score of the experimental group was significantly decreased compared with that of the control group. At the end of follow-up，the mean score of the experimental group was lower than that of the control group，with no statistically significant difference. In terms of the incidence of complications，severe cases， and critical cases， there were no complications，severe cases， and critical cases in the two groups，without a statistically significant difference. ConclusionThe symptom improvement effect and negative antigen conversion rate of Qingxuan Daozhi formula in the treatment of influenza in children （heat accumulation in the lung and stomach syndrome） are not inferior to Oseltamivir Phosphate granules， and children's acceptance is better. It can be more widely used in clinical treatment of influenza in children （heat accumulation in the lung and stomach syndrome）.

Objective:To develop a modified University of Wisconsin preservation solution (UW solution) containing α 2-adrenergic receptor agonists (dexmedetomidine) and noble gases (argon) and investigate its protective effect on the isolated amputated skeletal muscle of rats. Methods:Sixty male SD rats were selected to establish a hindlimb cold preservation/perfusion model and were divided into blank control group, hypothermic storage group, UW solution perfusion group, and modified UW solution perfusion group using a random number table, with 15 rats in each group. Simultaneously, a cold preservation model of rat skeletal muscle myoblasts (L6 cells) was established and the rats were also divided into four groups in the same way. Animal models were prepared in different ways: In the blank control group, the hindlimbs received no special treatment; In the hypothermic storage group, the amputated hindlimbs were stored in a dry centrifuge tube at 4℃ for 18 hours; In the UW solution perfusion group, the amputated hindlimbs were perfused with UW solution and then stored in a centrifuge tube containing UW solution at 4℃ for 18 hours; In the modified UW solution perfusion group, the amputated hindlimbs were perfused with modified UW solution (containing 0.1 nmol/L dexmedetomidine and 50% volume fraction of argon) and then stored in a centrifuge tube containing the modified UW solution at 4℃ for 18 hours. Cell models were treated as follows: In the blank control group, L6 cells were cultured under standard conditions; In the hypothermic storage group and UW solution group, L6 cells were treated with conventional culture medium or UW solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours; In the modified UW solution group, L6 cells were treated with the modified solution, stored in argon-filled sealed bags at 4℃ for 8 hours, and then rewarmed and cultured for 6 hours. After sample collection, skeletal muscle morphology, tissue edema and ultrastructure features were assessed by HE staining, wet-to-dry weight ratio, and transmission electron microscopy, respectively. Additionally, L6 cell morphology was examined by light microscopy. L6 cell viability was determined by cell counting kit-8 (CCK-8) assay (expressed as absorbance A value). Expression levels of glutathione peroxidase 4 (GPX4) protein in both skeletal muscle tissue and L6 cells were evaluated by immunofluorescence staining and Western blot, respectively.Results:After 18 hours of in vitro preservation of rat isolated amputated limbs, the following results were obtained: (1) HE staining results showed that the muscle fiber morphology of the modified UW solution perfusion group was close to that of the blank control group. Moreover, the area ratio of skeletal muscle cells in the modified UW solution perfusion group was significantly higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). (2) The wet-dry weight ratio results showed that there was no statistically significant difference among the modified UW solution perfusion group, the blank control group and UW solution group ( P>0.05), with significantly lower ratios in all three groups than that in the hypothermic storage group ( P<0.05). (3) Transmission electron microscopy results revealed that the modified UW solution perfusion group showed no statistically significant differences in ultrastructural metrics, including myofiber diameter, sarcomere length, mitochondrial short-axis/long-axis ratio, and mitochondrial cristae count, compared with those in the blank control group ( P>0.05), and performed significantly better than both the hypothermic storage group and UW solution perfusion group ( P<0.05). (4) Morphological observation of L6 cells showed that the cellular morphology was regular in the modified UW solution perfusion group, close to that in the blank control group, while it was severely damaged in the hypothermic storage group. Moreover, the cells were reduced in number and partially damaged in the UW solution group. The sequence of cell viability expressed as absorbance A value was blank control group >modified UW solution perfusion group > UW solution perfusion group > hypothermic storage group, with statistically significant differences among the four groups ( P<0.05). (5) Immunofluorescence staining showed that there was no statistically significant difference in fluorescence intensity of GPX4 protein expression between the modified UW solution perfusion group and blank control group ( P>0.05), while the fluorescence intensity was higher in the modified UW solution perfusion group than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Western blot analysis showed that the relative expression level of GPX4 in the modified UW solution group was significantly lower than that in the blank control group ( P<0.05), but higher than that in the hypothermic storage group and UW solution perfusion group ( P<0.05). Conclusion:The modified UW solution can stabilize the expression level of GPX4 protein, thereby inhibiting ferroptosis and alleviating cold preservation injury in both rat amputated isolated limb skeletal muscle tissue and L6 cells.

Objective:To investigate the influencing factors of diarrhea during early enteral nutrition(EEN)therapy in severe patients with temporary ileostomy.Method:A total of 154 patients with temporary ileostomy who received EEN in the Department of General Surgery,Jinling Hospital from November 2019 to November 2023 were included in this study.All patients were divided into two groups:the diarrhea group(n=43)and the non-diarrhea group(n=111).The clinical data of the patients were retrospectively collected and analyzed,and univariate analysis was performed to compare the differences between groups.The indicators with significant differences were subjected to multivariate logistic regression analysis to determine the influencing factors of diarrhea during EEN therapy in severe patients with temporary ileostomy.Result:Among the 154 patients,43 developed diarrhea during EEN therapy,with an incidence of 27.9%.Multivariate logistic regression analysis showed that enteral nutrition(EN)infusion rate(OR=6.342,P=0.001,95%CI:2.055～19.572),antibiotics type(OR=8.342,P=0.013,95%CI:1.577～44.119),mechanical ventilation(OR=7.011,P=0.001,95%CI:2.272～21.629),EN formulation type(OR=6.497,P=0.001,95%CI:2.177～19.392),and diabetes(OR=3.321,P=0.036,95%CI:1.080～10.215)were closely associated with EN-related diarrhea in severe patients with temporary ileostomy.Conclusion:There was a high incidence of diarrhea in severe patients with temporary ileostomy who received EEN.EN infusion rate,antibiotics use,mechanical ventilation,EN formulation type and diabetes were the influencing factors for presence of EEN-related diarrhea in the patients.Our data could provide a reference for preventing EEN-related diarrhea in severe patients with temporary ileostomy after surgery.

Objective To explore the sex differences in drug metabolism of sufentanil in Chinese patients based on the mutation classification of cytochrome P450 3A(CYP3A)enzymes.Methods According to the possible effects of combined cytochrome P450 3A4 gene*1G locus(CYP3A4*1G)and cytochrome P450 3A5 gene*3 locus(CYP3A5*3)mutation groups on Chinese population,we added different weights to CYP3A4*1G and CYP3A5*3 polymorphisms and classified patients into 3 groups:GroupⅠ,patients carried either the CYP3A4*1G/*1G allele or both CYP3A4*1/*1G allele and CYP3A5*3/*3 allele;Group Ⅱ,patients with both CYP3A4*1/*1G allele and CYP3A5*1/*3 allele;Group Ⅲ,patients with either the CYP3A4*1/*1 allele or both CYP3A4*1/*1G allele and CYP3A5*1/*1 allele.A single-dose,double-blind,stratified random sampling was performed,and 255 patients undergoing endoscopic surgery in the First Affiliated Hospital of Army Medical University were finally subjected.According to the results of genetic testing,an independent statistician,before operation,randomly selected 30 patients from each stratified group to form a study cohort(male-female ratio of 1∶1)and named each group A,B or C.Clinical investigators and subjects kept double-blind to the results of grouping and genetic testing.After entering the operating room,the subjected 90 patients received a single dose of sufentanil followed by collection of blood samples at 10 time points including 2 min before and from 2 to 120 min after administration.After the surgery,we determined the plasma drug concentration,calculated the pharmacokinetic parameters,and compared the metabolic differences between different genders in each group and unblinded the study.Results The cohort best fitted the two-compartment pharmacokinetic model,and groups A,B and C corresponded to group Ⅰ,Ⅱand Ⅲ,respectively.In different patient groups based on mutatron types of CYP3A enzymes the females had lower plasma drug concentration-time curves at each time point,higher systemic clearance(P≤0.01)and smaller area under the plasma concentration-time curve from zero to infinity(P＜0.05)when compared with the males.In addition,in group Ⅰ,the elimination rate of central compartment and movement rate of drug from central compartment to peripheral compartment were obviously greater in the females than the males(P＜0.05),while the distribution half-life(P＜0.05)and elimination half-life(P＜0.01)were notably longer in the males than the females.In both group Ⅱ and group Ⅲ,the males obtained larger total area under the plasma concentration-time curve than the females(P＜0.05).Conclusion There are sex differences in the drug metabolism of sufentanil in Chinese patients.Women show faster distribution and higher clearance of sufentanil while men present greater drug exposure.Preoperative CYP3A genotyping and intraoperative personalized medication are of great significance to ensure the safety in clinical practice.

Objective To establish a mouse model of bronchiectasis with acute infection and evaluate the immunogenicity and protective effect of a self-assembling Pseudomonas aeruginosa(PA)nanoparticle vaccine rePO-FN based on fusion of PcrV-OprI(rePO)protein with self-assembling ferritin(Ferritin).Methods ① SPF-grade female C57BL/6 mice(aged 6～8 weeks,weighing 18～20 g)were randomly allocated into normal saline group,and low-,medium-and high-dose elastase groups(n=6).A mouse model of bronchiectasis was established via intratracheal instillation of different doses of elastase(30 μL of normal saline containing 0.65,1.30 and 2.60 IU elastase)for 3 consecutive days.At 14 and 21 d after modeling,ELISA and HE staining were performed respectively to detect the concentration of IL-6 and to observe pathological changes in lung tissue in order to confirm the modeling.② A recombinant plasmid encoding the gene of fusion protein rePO-FN was constructed and expressed in E.coli.The target protein was purified via affinity chromatography and renatured to obtain the desired protein.The physicochemical properties of the rePO-FN protein were characterized using SDS-PAGE protein gel electrophoresis,dynamic light scattering,molecular sieve chromatography,and transmission electron microscopy.③ C57BL/6J mice were randomly divided into PBS group,rePO group,rePO-FN group,and Ferritin group(n=10).The mice in the above groups were immunized intramuscularly with 100 μL PBS buffer alone or containing 10 μg of corresponding proteins on days 0,7,and 14.ELISA was used to measure the specific antibodies in serum.In 7 d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the PBS,rePO,and rePO-FN groups.After establishing a bronchiectasis model by intratracheal instillation of 2.60 IU of elastase in C57BL/6J mice as described above,the mice were randomly divided into bronchiectasis PBS group,bronchiectasis rePO group,and bronchiectasis rePO-FN group(n=10).Immunization was conducted at the same dose and procedure as described above,in 21 d after bronchiectasis modeling.At the 7th d after the final immunization,an acute PA infection model was used to compare the survival rates and bacterial colonization among the groups.Results ①Repeated intratracheal instillation of elastase significantly increased the concentration of IL-6 in the lung tissue when compared to the content of the normal saline group(P＜0.05).Pathological observations revealed varying degrees of bronchial wall destruction,alveolar fusion,edema,neutrophil infiltration,and hemorrhage,with the severity increasing with elastase dose,which confirming successful establishment of the mouse model of bronchiectasis.② Well-dispersed rePO-FN nanoparticles were successfully prepared,with an average particle size of 91.28 nm,a Zeta potential of approximately-6.5 mV,and a polydispersity index(PDI)of 0.306.Molecular sieve chromatography determined the elution volume of rePO-FN protein to be 8.80 mL,corresponding to a molecular weight of approximately 1 400 kDa.③ Under acute PA XN-1 strain infection,the survival rate of the rePO-FN immunization group and the bronchiectasis rePO-FN immunization group were significantly higher than that of the PBS control group(P＜0.05).Additionally,bacterial colonization in the lung tissues was significantly lower in the rePO-FN immune group and the bronchiectasis rePO-FN immune group under acute PA XN-1 strain infection than that in the rePO group and the bronchiectasis rePO group(P＜0.05).Conclusion Our vaccine rePO-FN can effectively trigger a strong humoral immune response and provide significant protection against PA infection in a mouse bronchiectasis model.

Objective To explore the pharmacokinetic characteristics of sufentanil in individuals with normal body mass index(BMI),overweight BMI,and different CYP3A4/5 enzyme genotypes.Methods The patients receiving laparoscopic surgery under general anesthesia in the First Affiliated Hospital of Army Medical University from November 2020 to September 2021 were prospectively recruited in this study.Before the operation,the oral swabs were collected from all the patients for genotyping using the human CYP3A4/5 gene kit.Based on the potential impact of combination of their polymorphisms on sufentanil metabolism and the proportion of different genotype combinations of CYP3A4/5 enzymes,the patients were divided into groups I(3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation),II(3A4 heterozygous mutation+3A5 heterozygous mutation),and III(3A4 wild type or 3A4 heterozygous mutation+3A5 wild type).According to their BMI,they were also assigned into a normal body weight group(18.5～24.0 kg/m2)and an overweight group(24～<28 kg/m2),and the differences in drug metabolism parameters were statistically analyze between the 2 groups.After routine general anesthesia induction(sufentanil 0.5 μg/kg),venous blood samples were collected to detect the changes in its concentration using high performance liquid chromatography-mass spectrometry(HPLC-MS).The pharmacokinetic data of sufentanil were calculated between the normal BMI group and overweight group in all participants and between the 2 body weight groups among those with different genotype combinations.Results Among the 90 participants completing the blood drug concentration test,8 patients had their blood samples contaminated(including 1 case with an anesthesia duration of<2 h),and 3 were excluded due to low weight or overweight.Eventually,79 participants were included in the pharmacokinetic analysis on the normal body weight group and the overweight group.Compared with the normal body weight group,the central compartment volume of distribution in the overweight group was significantly reduced(P<0.05),while no obvious differences were observed between the 2 groups in terms of peripheral compartment volume of distribution,total clearance rate,peripheral compartment clearance rate,distribution half-life,clearance half-life,and area under the blood concentration-time curve.In group Ⅰ(n=26),the overweight patients(n=13)had significantly reduced central compartment volume of distribution,peripheral compartment volume of distribution,and peripheral compartment clearance rate when compared with the normal body weight patients(n=13)(P<0.05),while no differences were observed in other pharmacokinetic parameters.In groups Ⅱ(n=25)and Ⅲ(n=28),the overweight patients and normal body weight patients had no statistical differences in all pharmacokinetic parameters.Conclusion Among the patients with the same genotype combination of CYP3A4/5 mutations,there was no difference in the metabolism of sufentanil between the overweight and normal weight patients.Additionally,in the population of 3A4 homozygous mutation or 3A4 heterozygous mutation+3A5 homozygous mutation,the overweight patients have smaller peripheral distribution range of sufentanil,and weakened metabolic process.

Objective:To investigate the association of monocyte-to-high-density lipoprotein cholesterol ratio (MHR) with the severity of white matter hyperintensities (WMHs) and its spatial distribution.Methods:Patients admitted to the Department of Neurology, Jiangning Hospital Affiliated to Nanjing Medical University due to various chronic diseases or physical examinations between January 2023 and December 2024 were included retrospectively. Past medical history, clinical and imaging data were collected. The Fazekas scale was used to assess the severity of WMHs. According to the scoring results of periventricular WMHs (PVWMHs) and deep WMHs (DWMHs), WMHs were divided into no/mild group (0-1 points) and moderate/severe group (2-3 points). Multivariate logistic regression analysis was used to determine independent correlation factors for the severity of WMHs, PVWMHs, and DWMHs. Results:A total of 357 patients were included, aged 65.42±9.95 years, with 198 males (55.5%). There were 193 patients (54.1%) in the no/mild group and 164 (45.9%) in the moderate/severe group. Univariate analysis showed that the proportion of patients with hypertension, diabetes, history of cerebral infarction and cerebral hemorrhage, carotid plaque, and age, serum creatinine, monocyte count and MHR in the moderate/severe group were significantly higher than those in the no/mild group (all P<0.05). Multivariate logistic regression analysis showed a significant positive correlation between MHR and the severity of WMHs (odds ratio 3.138, 95% confidence interval 1.042-9.451; P=0.042). Further analysis showed a significant positive correlation between MHR and PVWMHs (odds ratio 3.384, 95% confidence interval 1.111-10.305; P=0.032), but no independent correlation with DWMHs. In addition, age and hypertension, diabetes, history of cerebral infarction and cerebral hemorrhage were significantly positively correlated with the severity of WMHs, PVWMHs and DWMHs. Conclusion:MHR is correlated with the severity of WMHs, and higher MHR is significantly associated with PVWMHs, but not with DWMHs.

ObjectiveTo investigate the effect of Danggui Shaoyaosan on ferroptosis in the rat model of non-alcoholic fatty liver disease （NAFLD） and explore the underlying mechanism based on the nuclear factor E₂-related factor 2 （Nrf2）/solute carrier family 7 member 11 （SLC7A11）/glutathione peroxidase 4 （GPX4） signaling pathway. MethodsThe sixty SD rats were randomly grouped as follows： control， model， Yishanfu （0.144 g·kg^-1）， and low-， medium-， and high-dose （2.44， 4.88， and 9.76 g·kg^-1， respectively） Danggui Shaoyaosan. A high-fat diet was used to establish the rat model of NAFLD. After 12 weeks of modeling， rats were treated with corresponding agents for 4 weeks. Then， the body weight and liver weight were measured， and the liver index was calculated. At the same time， serum and liver samples were collected. The levels or activities of total cholesterol （TC）， triglycerides （TG）， alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， and Fe²⁺ in the serum and TC， TG， free fatty acids （FFA）， malondialdehyde （MDA）， superoxide dismutase （SOD）， glutathione peroxidase （GPX）， and Fe²⁺ in the liver were measured. Hematoxylin-eosin staining and oil red O staining were employed to observe the pathological changes in the liver. Immunofluorescence was used to assess the reactive oxygen species （ROS） content in the liver. Mitochondrial morphology was observed by transmission electron microscopy. The protein levels of Nrf2， SLC7A11， GPX4， transferrin receptor 1 （TFR1）， and divalent metal transporter 1 （DMT1） in the liver were determined by Western blot. ResultsCompared with the control group， the model group showed increases in the body weight， liver weight， liver index， levels or activities of TC， TG， ALT， AST， and Fe²⁺ in the serum， levels of TC， TG， FFA， MDA， Fe²⁺， and ROS in the liver， and protein levels of TFR1 and DMT1 in the liver （P<0.01）， and decreases in the activities of SOD， GPX and the protein levels of Nrf2， SLC7A11， and GPX4 in the liver （P<0.05， P<0.01）. Meanwhile， the liver tissue in the model group presented steatosis， iron deposition， mitochondrial shrinkage， and blurred or swollen mitochondrial cristae. Compared with the model group， all doses of Danggui Shaoyaosan reduced the body weight， liver weight， liver index， levels or activities of TC， TG， ALT， AST， and Fe²⁺ in the serum， levels of TC， TG， FFA， MDA， Fe²⁺， and ROS in the liver， and protein levels of TFR1 and DMT1 in the liver （P<0.01）， while increasing the activities of SOD and GPX and the protein levels of Nrf2， SLC7A11， and GPX4 in the liver （P<0.01）. Furthermore， Danggui Shaoyaosan alleviated steatosis， iron deposition， and mitochondrial damage in the liver. ConclusionDanggui Shaoyaosan may inhibit lipid peroxidation and ferroptosis by activating the Nrf2/SLC7A11/GPX4 signaling pathway to treat NAFLD.

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.

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.