ObjectiveThe accuracy of Y-chromosome haplogroup assignment is crucial for tracing paternal lineage in male samples. With the advancement of high-throughput sequencing technologies, high-density Y-SNP genotyping from whole-genome or array-based data has become a standard method for determiningY-chromosome haplogroups. This study systematically evaluated the performance of 4 commonly used high-density SNP genotyping systems—namely, the Global Screening Array (GSA), Chinese Genotyping Array (CGA), Affymetrix array, and the 1240K capture panel—for haplogroup assignment. This work provides a reference for data comparison across different systems. MethodsWe extracted genotype data for the 4 Y-SNP panels from 30× whole-genome sequencing (WGS) data of 1 590 male samples from the 1000 Genomes Project. Additionally, GSA array genotype data from 384 relative pairs (spanning 1st- to 12th-degree relationships) from 109 Chinese Han families were collected. Haplogroup assignment was performed using Y-LineageTracker v1.3.0 software. We assessed the concordance and resolution of haplogroup assignments between the four Y-SNP panels and the WGS data. The consistency and resolution of haplogroup assignments were also evaluated for both the 1000 Genomes Project samples and the 109 family samples collected in this study. Furthermore, the impact of varying numbers of Y-SNPs on haplogroup assignment was examined. ResultsThe GSA and CGA panels demonstrated superior resolution and discrimination of haplogroup subclades compared with the other two panels. The haplogroup assignments from the GSA, CGA, and 1240K panels showed high concordance with WGS data, with consistency rates exceeding 88.70%, whereas the Affymetrix platform exhibited a significantly lower consistency rate of 61.89%. Specifically, the GSA and CGA panels consistently demonstrated superior performance compared with the other two panels in the assignment of haplogroups O-M175 and H-L901, achieving complete concordance (100%) for both haplogroups. In contrast, the Affymetrix panel erroneously assigned all individuals belonging to haplogroup O-M175 to haplogroup K2-M526. Furthermore, its accuracy for haplogroup H-L901 was exceedingly low, at merely 1.41%. This poor performance was characterized by the misassignment of 98.59% of H-L901 samples—specifically, 1.41% to J-M304 and a predominant 97.18% to F-M89. For haplogroup R-M207, all four panels exhibited uniformly high levels of consistency, with concordance values exceeding 94.00%. Notably, for haplogroup E-M96, the 1240K and Affymetrix panels outperformed the GSA and CGA panels in terms of concordance, representing the first instance in which these two panels surpassed the latter. Conversely, for haplogroups J-M304, Q-M242, and I-M170, all 4 panels showed relatively elevated misclassification rates, with the Affymetrix array demonstrating the poorest overall performance. None of the four panels showed any discordant haplogroup assignments among the familial relative pairs analyzed. A positive correlation was observed between the number of Y-SNPs (ranging from 1 000 to 10 000) and classification consistency; however, classification consistency plateaued when the number of Y-SNPs exceeded 10 000. Furthermore, a random sampling analysis conducted on the GSA and CGA panels demonstrated that the haplogroup misclassification rate exhibited negligible fluctuation across the Y-SNP range of 500 to 1 000. Conversely, a marked enhancement in classification consistency was observed as the number of markers increased from 1 000 to 5 000, ultimately reaching a plateau within the interval of 5 000 to 8 000 markers. ConclusionThese findings indicate that the GSA and CGA panels provide high resolution and concordance, delivering reliable Y-haplogroup assignment for forensic investigations.

ObjectiveThe accuracy of Y-chromosome haplogroup assignment is crucial for tracing paternal lineage in male samples. With the advancement of high-throughput sequencing technologies, high-density Y-SNP genotyping from whole-genome or array-based data has become a standard method for determiningY-chromosome haplogroups. This study systematically evaluated the performance of 4 commonly used high-density SNP genotyping systems—namely, the Global Screening Array (GSA), Chinese Genotyping Array (CGA), Affymetrix array, and the 1240K capture panel—for haplogroup assignment. This work provides a reference for data comparison across different systems. MethodsWe extracted genotype data for the 4 Y-SNP panels from 30× whole-genome sequencing (WGS) data of 1 590 male samples from the 1000 Genomes Project. Additionally, GSA array genotype data from 384 relative pairs (spanning 1st- to 12th-degree relationships) from 109 Chinese Han families were collected. Haplogroup assignment was performed using Y-LineageTracker v1.3.0 software. We assessed the concordance and resolution of haplogroup assignments between the four Y-SNP panels and the WGS data. The consistency and resolution of haplogroup assignments were also evaluated for both the 1000 Genomes Project samples and the 109 family samples collected in this study. Furthermore, the impact of varying numbers of Y-SNPs on haplogroup assignment was examined. ResultsThe GSA and CGA panels demonstrated superior resolution and discrimination of haplogroup subclades compared with the other two panels. The haplogroup assignments from the GSA, CGA, and 1240K panels showed high concordance with WGS data, with consistency rates exceeding 88.70%, whereas the Affymetrix platform exhibited a significantly lower consistency rate of 61.89%. Specifically, the GSA and CGA panels consistently demonstrated superior performance compared with the other two panels in the assignment of haplogroups O-M175 and H-L901, achieving complete concordance (100%) for both haplogroups. In contrast, the Affymetrix panel erroneously assigned all individuals belonging to haplogroup O-M175 to haplogroup K2-M526. Furthermore, its accuracy for haplogroup H-L901 was exceedingly low, at merely 1.41%. This poor performance was characterized by the misassignment of 98.59% of H-L901 samples—specifically, 1.41% to J-M304 and a predominant 97.18% to F-M89. For haplogroup R-M207, all four panels exhibited uniformly high levels of consistency, with concordance values exceeding 94.00%. Notably, for haplogroup E-M96, the 1240K and Affymetrix panels outperformed the GSA and CGA panels in terms of concordance, representing the first instance in which these two panels surpassed the latter. Conversely, for haplogroups J-M304, Q-M242, and I-M170, all 4 panels showed relatively elevated misclassification rates, with the Affymetrix array demonstrating the poorest overall performance. None of the four panels showed any discordant haplogroup assignments among the familial relative pairs analyzed. A positive correlation was observed between the number of Y-SNPs (ranging from 1 000 to 10 000) and classification consistency; however, classification consistency plateaued when the number of Y-SNPs exceeded 10 000. Furthermore, a random sampling analysis conducted on the GSA and CGA panels demonstrated that the haplogroup misclassification rate exhibited negligible fluctuation across the Y-SNP range of 500 to 1 000. Conversely, a marked enhancement in classification consistency was observed as the number of markers increased from 1 000 to 5 000, ultimately reaching a plateau within the interval of 5 000 to 8 000 markers. ConclusionThese findings indicate that the GSA and CGA panels provide high resolution and concordance, delivering reliable Y-haplogroup assignment for forensic investigations.

Objective:To investigate the application effect of aleximumab combined with ivabradine in patients with STEMI after PCI.Methods:A retrospective analysis was conducted on 90 STEMI patients admitted to Jiamusi Central Hospital for PCI treatment from October 2023 to October 2024.The patients were divided into two groups based on whether they were treated with aleximumab in the early stages of admission.The 45 patients treated with aleximumab combined with ivabradine were assigned to the experimental group,and the 45 patients treated with ivabradine were assigned to the matched group.Compare two groups of blood lipid metabolism indicators[Low density lipoprotein cholesterol(LDL-C),triglycerides,total cholesterol],inflammatory factors[interleukin-6(IL-6),matrix metalloproteinase-9(MMP-9),hypersensitive C-reactive protein(Hs CRP)],ventricular remodeling[Left ventricular mass index(LVMI),end diastolic interventricular thickness(LVST)],and carotid plaques[plaque score,plaque area,carotid intima-media thickness(CarST)].otid intima-media thickness(IMT)was observed,and patients were followed up by telephone and outpatient follow-up for 6 months to record the incidence of cardiovascular adverse events(MACE).Results:Post-treatment,the level of lipid metabolism in both groups was lower than that pretherapy,and the level of lipid metabolism in the test group was lower than that in the matched group(P＜0.05);Post-treatment,the levels of inflammatory factors in both groups were lower than that pretherapy,and the test group was lower than that in the matched group(P＜0.05);Post-treatment,t-test showed that LVMI LVST,The plaque score,plaque area,and TMT level were all lower than pretherapy,and the experimental group was lower than the matched group(P＜0.05);All patients were followed up for 6 months after surgery.Through follow-up,it was found that the total incidence of MACE in the experimental group was 8.89％,while that in the matched group was 26.67％.According to the chi square test,the total incidence of MACE in the experimental group was lower than that in the matched group(P＜0.05).Conclusion:The combination of aleximumab and ivabradine treatment after PCI in STEMI patients can further improve the patient's lipid metabolism,reduce the body's inflammatory response,reverse some carotid plaques,improve ventricular remodeling,and thus further reduce the risk of long-term cardiovascular adverse events in patients.

AIM To evaluate the quality of Gegen Formula Granules.METHODS Linear calibration with two reference substances(LCTRS)was adopted in the predicting of retention time with puerarin and daidzein as internal standards.UPLC characteristic chromatograms were established.The contents of 3'-hydroxy puerarin,puerarin(internal standard),3'-methoxy puerarin,puerarin 6"-O-xyloside,puerarin apioside and daidzin were determined by quantitative determination analysis multi-components by a single marker(QAMS),after which their transfer rates were calculated.RESULTS Compared with relative retention time method,LCTRS demonstrated higher positional accuracy for characteristic peaks and wider application range for columns.There were 9 characteristic peaks in the characteristic chromatograms for 14 batches of formula granules and 15 batches of standard decoctions with the similarities of more than 0.95.The contents and transfer rates of various constituents in formula granules and standard decoctions were basically consistent.CONCLUSION The chemical constituents in formula granules and their standard decoctions of Puerariae lobatae Radix display good consistency,reliable preparation process is observable in the former.

OBJECTIVE: To observe the clinical symptoms and MRI outcomes of patients with ruptured lumbar disc herniation(LDH) through a multicenter randomized controlled study, and to evaluate the clinical efficacy and safety of Yiqi Huoxue formula() in the treatment of this disease. METHODS: A total of 160 outpatients and inpatients with ruptured LDH admitted to 4 medical centers from January 2023 to June 2023 were selected and randomly divided into the Yiqi Huoxue formula group and the control group, with 80 patients in each group. In the Yiqi Huoxue formula group, there were 43 males and 37 females, with an age of (41.03±9.56) years and a disease duration of (10.45±25.37) days, and the patients were treated with Yiqi Huoxue formula. In the control group, there were 34 males and 46 females, with an age of (42.14±8.73) years and a disease duration of (11.31±21.14) days;during the acute phase, patients in this group could take celecoxib capsules orally, and methylcobalamin orally at the same time. The Japanese Orthopaedic Association (JOA) score, Oswestry disability index (ODI), changes in the volume of herniated disc tissue on MRI, herniation rate, and absorption rate were recorded at the time of enrollment and during follow-ups at the 3rd, 6th, and 12th month after treatment. RESULTS: A total of 156 patients completed the clinical follow-up, and 4 patients withdrew midway. The clinical symptoms of all patients who completed the study were relieved to varying degrees, and reabsorption of herniated disc tissue was observed in all patients in the Yiqi Huoxue formula group after treatment. For the JOA score:in the Yiqi Huoxue formula group, it was (10.73±2.76) points before treatment and (24.65±2.19) points at the 12th month after treatment;in the control group, it was (11.01±1.20) points before treatment and (17.07±3.26) points at the 12th month after treatment. For the ODI score:in the Yiqi Huoxue formula group, it was (26.21±3.55) points before treatment and (5.65±2.19) points at the 12th month after treatment;in the control group, it was (27.92±2.51) points before treatment and (9.09±2.15) points at the 12th month after treatment. At the 12th month after treatment, the JOA and ODI scores of both groups were better than those before treatment, and the scores of the Yiqi Huoxue formula group were better than those of the control group, with statistically significant differences (P<0.05). In terms of the herniated disc volume and herniation rate on MRI, the Yiqi Huoxue formula group was superior to the control group, with statistically significant differences(P<0.05). Reabsorption occurred in 56.96%(45/79) of patients in the Yiqi Huoxue formula group, which was significantly higher than the 37.66%(29/77) in the control group. CONCLUSION After treatment with Yiqi Huoxue formula, patients with ruptured LDH show significant improvement in clinical symptoms and a marked reduction in the volume of herniated discs. During the follow-up period, no obvious adverse drug reactions are observed in patients, and no recurrence of symptoms is found at the last follow-up, indicating that the formula has safe and reliable efficacy.
Humans ; Male ; Female ; Intervertebral Disc Displacement/drug therapy* ; Adult ; Drugs, Chinese Herbal/adverse effects* ; Middle Aged ; Lumbar Vertebrae

Aim To explore the effects of high glucose on KIAA0753 and CCSAP and the relationship between KIAA0753 and CCSAP and osteogenic differentiation and calcium signaling pathway under high glucose con-ditions.Methods Mouse embryonic osteoblast pre-cursor cells(MC3T3-E1)were induced by osteoblast medium with glucose concentrations of 5.5 and 25 mmol·L-1,and the protein expressions of KIAA0753 and CCSAP were detected by Western blot.The over-expressed plasmid was transfected into human embry-onic kidney cells(HEK-293T),and the interaction between KIAA0753 and CCSAP was detected by co-im-munoprecipitation.MC3T3-E1 cells were treated in the osteogenic medium with different glucose concentrations and induction times.Alkaline phosphatase(ALP)ac-tivity was detected with a kit.The expression of KI-AA0753,CCSAP,osteopontin,osteocalcin,and other proteins were assessed using Western blot.and then 5.5,25 mmol·L-1,and 25 mmol·L-1+OE-CCSAP three groups of MC3T3-E1 cells were set.The expression of KIAA0753,OCN,OPN protein,and ALP activity were detected successively.The diabetic mouse model dataset in Gene Expression Omnibus was used to screen differential genes for bioinformatics a-nalysis.MC3T3-E1 cells were set up in three groups,5.5,25 mmol·L-1,and 25 mmol·L-1+OE-KI-AA0753,respectively.The calcium/calmodulin-de-pendent protein kinase Ⅱ beta(CAMK2B)and phos-pholamban(PLN)were detected by Western blot.Re-sults Compared with the 5.5 mmol·L-1 group,25 mmol·L-1 inhibited the expression of KIAA0753 and CCSAP proteins in osteoblasts,and there was an inter-action between KIAA0753 and CCSAP.At the same time,25 mmol·L-1 also inhibited the expression of ALP,OPN,and OCN proteins in osteoblasts.Overex-pression of CCSAP at 25 mmol·L-1 up-regulated the expression of KIAA0753,OCN,OPN,and ALP.The differential genes of the diabetic mouse model were mainly concentrated in the aspects of"signal receptor and signal regulation".25 mmol·L-1 glucose inhibi-ted the expression of CAMK2B and PLN proteins in os-teoblasts,and overexpression of KIAA0753 at 25 mmol·L-1 upregulated the expression of CAMK2B and PLN proteins.Conclusions High glucose inhibits the expression of KIAA0753 and CCSAP protein,inhibits the osteogenic differentiation and calcium signaling in mouse embryonic osteoblast precursor cells,overex-pression of CCSAP saves the inhibitory effect of high glucose on osteogenic differentiation,and overexpres-sion of KIAA0753 reverses the inhibitory effect of high glucose on calcium signaling pathway.

Objective:To describe the body mass index (BMI) level and long-term trends of Chinese older adults aged 65 and above.Methods:Older adults aged 65 and above from six waves (2002-2018) of the China Longitudinal Healthy Longevity Survey were selected as the study population. Multiple cross-sectional design with six survey waves conducted in 2002, 2005, 2008, 2011, 2014, and 2018 was adopted, enrolling 15 647, 15 358, 15 622, 9 166, 6 302, and 12 417 participants, respectively. Additionally, a total of 13, 755 participants were included in the cohort study design. Relevant information was collected through questionnaires and physical examinations. The χ2 trend test was used to compare the changes in the rates of underweight and overweight/obesity over the years, and the linear mixed-e?ects model (LMM) was used to fit trajectory curves of BMI changes with advancing age in older adults. Results:The baseline ages of the participants included in 2002, 2005, 2008, 2011, 2014, and 2018 were (85.16±11.26), (84.23±11.83), (84.99±12.16), (81.10±11.86), (78.89±11.30), and (83.08±12.42) years, respectively, with a relatively high proportion of females and rural residents. In the cohort study, the 13 755 participants had a median ( Q1, Q3) follow-up time of 6.5 (5.2, 10.0) years, with a cumulative follow-up duration of 109 041 person-years. In each wave, males had higher BMI than females, urban residents had higher BMI than rural residents, and BMI gradually decreased with increasing age (all P<0.001). The mean BMI of older adults in China increased from (19.37±3.80) kg/m2 in 2002 to (22.04±4.01) kg/m2 in 2018 ( P<0.001). Across all survey years, the prevalence of underweight was consistently higher in women than in men and in rural areas than in urban areas, with an upward trend as age increased (all P<0.001). In 2018, the underweight rates in the 65-79, 80-89, 90-99, and ≥100-year-old age groups were 8.0%, 16.7%, 26.2%, and 35.5%, respectively. Meanwhile, the prevalence of overweight/obesity was higher in men than in women and in urban areas than in rural areas, showing a declining trend with advancing age (all P<0.001). The prevalence of underweight among the older adults decreased significantly from 45.2% in 2002 to 18.9% in 2018 ( P<0.001), while the prevalence of overweight/obesity increased from 11.0% in 1998 to 29.6% in 2018 ( P<0.001). The trajectory curves fitted by the LMM model showed that individuals born in later decades had higher BMI levels at the same age compared to earlier cohorts. Conclusion:From 2002 to 2018, the BMI level among Chinese older adults showed an increasing trend. The prevalence of underweight showed a declining trend, while the rates of obesity and overweight increased. However, the underweight rate remained notably high among the oldest old.

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 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.

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.