Objective To investigate the distribution and antimicrobial resistance profiles of the common pathogens isolated from urine from 2015 to 2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods The bacterial strains were isolated from urine and identified routinely in 51 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Antimicrobial susceptibility was determined by Kirby-Bauer method,automatic microbiological analysis system and E-test according to the unified protocol.Results A total of 261 893 nonduplicate strains were isolated from urine specimen from 2015 to 2021,of which gram-positive bacteria accounted for 23.8％(62 219/261 893),and gram-negative bacteria 76.2％(199 674/261 893).The most common species were E.coli(46.7％),E.faecium(10.4％),K.pneumoniae(9.8％),E.faecalis(8.7％),P.mirabilis(3.5％),P.aeruginosa(3.4％),SS.agalactiae(2.6％),and E.cloacae(2.1％).The strains were more frequently isolated from inpatients versus outpatients and emergency patients,from females versus males,and from adults versus children.The prevalence of ESBLs-producing strains in E.coli,K.pneumoniae and P.mirabilis was 53.2％,52.8％and 37.0％,respectively.The prevalence of carbapenem-resistant strains in E.coli,K.pneumoniae,P.aeruginosa and A.baumannii was 1.7％,18.5％,16.4％,and 40.3％,respectively.Lower than 10％of the E.faecalis isolates were resistant to ampicillin,nitrofurantoin,linezolid,vancomycin,teicoplanin and fosfomycin.More than 90％of the E.faecium isolates were ressitant to ampicillin,levofloxacin and erythromycin.The percentage of strains resistant to vancomycin,linezolid or teicoplanin was＜2％.The E.coli,K.pneumoniae,P.aeruginosa and A.baumannii strains isolated from ICU inpatients showed significantly higher resistance rates than the corresponding strains isolated from outpatients and non-ICU inpatients.Conclusions E.coli,Enterococcus and K.pneumoniae are the most common pathogens in urinary tract infection.The bacterial species and antimicrobial resistance of urinary isolates vary with different populations.More attention should be paid to antimicrobial resistance surveillance and reduce the irrational use of antimicrobial agents.

Objective To understand the distribution and changing resistance profiles of clinical isolates of Enterococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Enterococcus according to the unified protocol of CHINET program by automated systems,Kirby-Bauer method,or E-test strip.The results were interpreted according to the Clinical & Laboratory Standards Institute(CLSI)breakpoints in 2021.WHONET 5.6 software was used for statistical analysis.Results A total of 124 565 strains of Enterococcus were isolated during the 7-year period,mainly including Enterococcus faecalis(50.7％)and Enterococcus faecalis(41.5％).The strains were mainly isolated from urinary tract specimens(46.9％±2.6％),and primarily from the patients in the department of internal medicine,surgery and ICU.E.faecium and E.faecalis strains showed low level resistance rate to vancomycin,teicoplanin and linezolid(≤3.6％).The prevalence of vancomycin-resistant E.faecalis and E.faecium was 0.1％and 1.3％,respectively.The prevalence of linezolid-resistant E.faecalis increased from 0.7％in 2015 to 3.4％in 2021,while the prevalence of linezolid-resistant E.faecium was 0.3％.Conclusions The clinical isolates of Enterococcus were still highly susceptible to vancomycin,teicoplanin,and linezolid,evidenced by a low resistance rate.However,the prevalence of linezolid-resistant E.faecalis was increasing during the 7-year period.It is necessary to strengthen antimicrobial resistance surveillance to effectively identify the emergence of antibiotic-resistant bacteria and curb the spread of resistant pathogens.

Objective To examine the changing antimicrobial resistance profile of Enterobacter spp.isolates in 53 hospitals across China from 2015 t0 2021.Methods The clinical isolates of Enterobacter spp.were collected from 53 hospitals across China during 2015-2021 and tested for antimicrobial susceptibility using Kirby-Bauer method or automated testing systems according to the CHINET unified protocol.The results were interpreted according to the breakpoints issued by the Clinical & Laboratory Standards Institute(CLSI)in 2021(M100 31st edition)and analyzed with WHONET 5.6 software.Results A total of 37 966 Enterobacter strains were isolated from 2015 to 2021.The proportion of Enterobacter isolates among all clinical isolates showed a fluctuating trend over the 7-year period,overall 2.5％in all clinical isolates amd 5.7％in Enterobacterale strains.The most frequently isolated Enterobacter species was Enterobacter cloacae,accounting for 93.7％(35 571/37 966).The strains were mainly isolated from respiratory specimens(44.4±4.6)％,followed by secretions/pus(16.4±2.3)％and urine(16.0±0.9)％.The strains from respiratory samples decreased slightly,while those from sterile body fluids increased over the 7-year period.The Enterobacter strains were mainly isolated from inpatients(92.9％),and only(7.1±0.8)％of the strains were isolated from outpatients and emergency patients.The patients in surgical wards contributed the highest number of isolates(24.4±2.9)％compared to the inpatients in any other departement.Overall,≤ 7.9％of the E.cloacae strains were resistant to amikacin,tigecycline,polymyxin B,imipenem or meropenem,while ≤5.6％of the Enterobacter asburiae strains were resistant to these antimicrobial agents.E.asburiae showed higher resistance rate to polymyxin B than E.cloacae(19.7％vs 3.9％).Overall,≤8.1％of the Enterobacter gergoviae strains were resistant to tigecycline,amikacin,meropenem,or imipenem,while 10.5％of these strains were resistant to polycolistin B.The overall prevalence of carbapenem-resistant Enterobacter was 10.0％over the 7-year period,but showing an upward trend.The resistance profiles of Enterobacter isolates varied with the department from which they were isolated and whether the patient is an adult or a child.The prevalence of carbapenem-resistant E.cloacae was the highest in the E.cloacae isolates from ICU patients.Conclusions The results of the CHINET Antimicrobial Resistance Surveillance Program indicate that the proportion of Enterobacter strains in all clinical isolates fluctuates slightly over the 7-year period from 2015 to 2021.The Enterobacter strains showed increasing resistance to multiple antimicrobial drugs,especially carbapenems over the 7-year period.

Objective To understand the changing distribution and antimicrobial resistance profiles of Proteus,Morganella and Providencia in hospitals across China from January 1,2015 to December 31,2021 in the CHINET Antimicrobial Resistance Surveillance Program.Methods Antimicrobial susceptibility testing was carried out following the unified CHINET protocol.The results were interpreted in accordance with the breakpoints in the 2021 Clinical & Laboratory Standards Institute(CLSI)M100(31 st Edition).Results A total of 32 433 Enterobacterales strains were isolated during the 7-year period,including 24 160 strains of Proteus,6 704 strains of Morganella,and 1 569 strains of Providencia.The overall number of these Enterobacterales isolates increased significantly over the 7-year period.The top 3 specimen source of these strains were urine,lower respiratory tract specimens,and wound secretions.Proteus,Morganella,and Providencia isolates showed lower resistance rates to amikacin,meropenem,cefoxitin,cefepime,cefoperazone-sulbactam,and piperacillin-tazobactam.For most of the antibiotics tested,less than 10％of the Proteus and Morganella strains were resistant,while less than 20％of the Providencia strains were resistant.The prevalence of carbapenem-resistant Enterobacterales(CRE)was 1.4％in Proteus isolates,1.9％in Morganella isolates,and 15.6％in Providencia isolates.Conclusions The overall number of clinical isolates of Proteus,Morganella and Providencia increased significantly in the 7-year period from 2015 to 2021.The prevalence of CRE strains also increased.More attention should be paid to antimicrobial resistance surveillance and rational antibiotic use so as to prevent the emergence and increase of antimicrobial resistance.

Objective To understand the changing distribution and antimicrobial resistance profiles of Klebsiella strains in 52 hospitals across China in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Antimicrobial susceptibility testing was carried out according to the unified CHINET protocol.The susceptibility results were interpreted according to the breakpoints in the Clinical & Laboratory Standards Institute(CLSI)M100 document.Results A total of 241,549 nonduplicate Klebsiella strains were isolated from 2015 to 2021,including Klebsiella pneumoniae(88.0％),Klebsiella aerogenes(5.8％),Klebsiella oxytoca(5.7％),and other Klebsiella species(0.6％).Klebsiella strains were mainly isolated from respiratory tract(48.49±5.32)％.Internal medicine(22.79±3.28)％,surgery(17.98±3.10)％,and ICU(14.03±1.39)％were the top 3 departments where Klebsiella strains were most frequently isolated.K.pneumoniae isolates showed higher resistance rate to most antimicrobial agents compared to other Klebsiella species.Klebsiella isolates maintained low resistance rates to tigecycline and polymyxin B.ESBLs-producing K.pneumoniae and K.oxytoca strains showed higher resistance rates to all the antimicrobial agents tested compared to the corresponding ESBLs-nonproducing strains.The K.pneumoniae and carbapenem-resistant K.pneumoniae(CRKP)strains isolated from ICU patients demonstrated higher resistance rates to majority of the antimicrobial agents tested than the strains isolated from non-ICU patients.The CRKP strains isolated from adult patients had higher resistance rates to most of the antimicrobial agents tested than the corresponding CRKP strains isolated from paediatric patients.Conclusions The prevalence of carbapenem-resistant strains in Klebsiella isolates increased greatly from 2015 to 2021.However,the Klebsiella isolates remained highly susceptible to tigecycline and polymyxin B.Antimicrobial resistance surveillance should still be strengthened for Klebsiella strains.

Objective To investigate the changing distribution and antibiotic resistance profiles of clinical isolates of Staphylococcus in hospitals across China from 2015 to 2021.Methods Antimicrobial susceptibility testing was conducted for the clinical isolates of Staphylococcus according to the unified protocol of CHINET(China Antimicrobial Surveillance Network)using disk diffusion method and commercial automated systems.The CHINET antimicrobial resistance surveillance data from 2015 to 2021 were interpreted according to the 2021 CLSI breakpoints and analyzed using WHONET 5.6.Results During the period from 2015 to 2021,a total of 204,771 nonduplicate strains of Staphylococcus were isolated,including 136,731(66.8％)strains of Staphylococcus aureus and 68,040(33.2％)strains of coagulase-negative Staphylococcus(CNS).The proportions of S.aureus isolates and CNS isolates did not show significant change.S.aureus strains were mainly isolated from respiratory specimens(38.9±5.1)％,wound,pus and secretions(33.6±4.2)％,and blood(11.9±1.5)％.The CNS strains were predominantly isolated from blood(73.6±4.2)％,cerebrospinal fluid(12.1±2.5)％,and pleural effusion and ascites(8.4±2.1)％.S.aureus strains were mainly isolated from the patients in ICU(17.0±7.3)％,outpatient and emergency(11.6±1.7)％,and department of surgery(11.2±0.9)％,whereas CNS strains were primarily isolated from the patients in ICU(32.2±9.7)％,outpatient and emergency(12.8±4.7)％,and department of internal medicine(11.2±1.9)％.The prevalence of methicillin-resistant strains was 32.9％in S.aureus(MRSA)and 74.1％in CNS(MRCNS).Over the 7-year period,the prevalence of MRSA decreased from 42.1％to 29.2％,and the prevalence of MRCNS decreased from 82.1％to 68.2％.MRSA showed higher resistance rates to all the antimicrobial agents tested except trimethoprim-sulfamethoxazole than methicillin-susceptible S.aureus(MSSA).Over the 7-year period,MRSA strains showed decreasing resistance rates to gentamicin,rifampicin,and levofloxacin,MRCNS showed decreasing resistance rates to gentamicin,erythromycin,rifampicin,and trimethoprim-sulfamethoxazole,but increasing resistance rate to levofloxacin.No vancomycin-resistant strains were detected.The prevalence of linezolid-resistant MRCNS increased from 0.2％to 2.3％over the 7-year period.Conclusions Staphylococcus remains the major pathogen among gram-positive bacteria.MRSA and MRCNS were still the principal antibiotic-resistant gram-positive bacteria.No S.aureus isolates were found resistant to vancomycin or linezolid,but linezolid-resistant strains have been detected in MRCNS isolates,which is an issue of concern.

Restoration of teeth after removal of previous restorations is a common problem in the dental clinic. The situation of teeth after removal of previous restoration is complex and often requires multidisciplinary cooperation. However, there is a lack of systematic and concise guidelines for determining the treatment plan for those teeth. Through a combination of restorative clinical experience and the opinions of endodontic specialists, the author systematically described the problems that may exist after the removal of previous restorations in the teeth that have not undergone or have undergone root canal treatment (RCT) and those with post and core restorations. And summarized the corresponding treatment recommendations according to their pulpal and periapical status, the quality of RCT and the presence or absence of post and core restorations. ①For teeth without RCT, the vitality of the pulp, the occurrence of pulpal/periapical disease and the amount of re-preparation need to be assessed to determine whether RCT is necessary. ②For teeth with RCT, if the quality of RCT is good and no periradicular lesion exists, direct restorative treatment can be considered. If the quality of the RCT is unsatisfactory but no periradicular lesion exists, root canal retreatent (re-RCT), follow up or direct restorative treatment should be performed as appropriate and treatment plan can be developed in conjunction with the endodontist if necessary. If the quality of the RCT is unsatisfactory and periradicular lesion exists, re-RCT is necessary before restorative treatment.③For teeth with post and core restorations, if the quality of RCT is good and no periradicular lesion exists, direct restorative treatment can be considered. If the quality of the RCT is unsatisfactory but no periradicular lesion exists, follow up or direct restorative treatment should be performed as appropriate and treatment plan can be developed in conjunction with the endodontist if necessary. If the quality of RCT is unsatisfactory and periradicular lesion exists, for teeth with thin post and thick root canal walls, re-RCT after removal of the post can be attempted. For teeth with thick post and thin root canal walls, preservation of the post and apical surgery can be considered. For the teeth with excessively large defects or extremely poor periodontal conditions, extraction is recommended. The author refined the above recommendations into a set of treatment procedures, aiming to provide a reference for the selection of treatment options for teeth after removal of previous restorations.

Objective To investigate the prevalence of colistin resistance and mcr-1 gene in pa-tients with bloodstream infection caused by Escherichia coli (E.coli) and Klebsiella pneumoniae (K.pneu-moniae) in Zhejiang Province. Methods A total of 869 clinical strains of the Enterobacteriaceae family, including 611 E.coli and 258 K.pneumonia strains, were isolated from patients with bloodstream infection (BSI) in Zhejiang Province from March 2014 to April 2015. Broth microdilution method and PCR were re-spectively performed to detect colistin resistance and mcr-1 gene in those stains. Susceptibilities of mcr-1-positive strains to other antibiotics were assessed by E-test. Pulsed-field gel electrophoresis(PFGE) and multilocus sequence typing(MLST) were used for molecular typing. Location of mcr-1 gene was determined by analysis of PFGE profiles of S1-digested genomic DNA and Southern blot hybridization. Plasmid transfer to E.coli recipients was investigated using filter mating test. Clinical data of the patients infected with mcr-1-positive strains was collected and analyzed. Results The minimum inhibitory concentration (MIC) values of colistin to the 869 Enterobacteriaceae strains ranged from ≤0.06 μg/ml to 16 μg/ml. Six (0.69%) E.coli strains were identified to be colistin-resistant and mcr-1-positive and the MIC values against them ranged from 8 μg/ml to 16 μg/ml. No colistin-resistant or mcr-1-positive K.pneumonia strain was identified. All mcr-1-positive strains were susceptible to carbapenems and most of them(83.33%,5/6) were suscepti-ble to tigecycline and β-lactamase inhibitor combinations tested in this study. The six mcr-1-positive strains were of different sequence types (STs) and the mcr-1 genes carried by them located on three types of plas-mids with the sizes of 33 kb,61 kb and 244.4 kb. Conclusion The prevalence of mcr-1 gene in E.coli and K.pneumonia strains isolated from patients with BSI in Zhejiang Province was relatively low, only ac-counting for 0.69% of all isolated Enterobacteriaceae strains.Those strains carrying mcr-1 gene showed low drug resistance to colistin. The mcr-1-positive strains were usually non-pathogenic clones and remained sus-ceptible to many antimicrobial agents, which was conducive to favorable outcomes. In order to clarify the clinical impact of this novel resistance gene on public health,further studies should be conducted.

Objective To explore the effects of Yishen-Jianpi decoction on bone mineral density (BMD) and serum sclerostin level in chronic atrophic gastritis in rats. Methods Wistar rats were randomly divided into normal control group, model group, Weimeisu group, low-, medium-and high-dose Yishen-Jianpi Decoction groups. Chronic atrophic gastritis was induced via depriving of water by replacement with 0.1%ammonia water for 180 days. After modeling, the rats in the Yishen-Jianpi decoction groups of low-, medium-and high-dose received intragastric administration of Yishen-Jianpi decoction of 7.5, 15, 30 g/(kg?d), respectively;the Weimeisu group received intragastric administration of Weimeisu suspension 0.28 g/(kg?d);the normal control group and the model group received intragastric administration of equivalent volume of normal saline. After 90 d continuous administration the specimens were drawn. The femur BMD and BMC were detected with dual energy X-ray absorptiometry. The serum sclerostin level was measured with enzyme-linked immunosorbent assay. The serum levels of parathyroid hormone (PTH) and human calcitonin (CT) were detected with radioimmunoassay. Results Compared with the normal control group (n=10), the femur BMD (0.168 ± 0.007 g/cm2 vs. 0.235 ± 0.029 g/cm2), BMC (0.383 ± 0.022 g vs. 0.637 ± 0.085 g), and the serum CT level (26.76 ± 11.54 pg/m vs. 33.85 ± 13.12 pg/ml) in the model group (n=9) were significantly decreased (all P<0.05), while the serum level of sclerostin (105.78 ± 34.43 pg/ml vs. 71.51 ± 23.21 pg/ml) and PTH (11.52 ± 4.34 ng/dl vs. 8.46 ± 2.39 ng/dl) were significantly increased (all P<0.05). Compared with the model group, the femur BMD (0.197 ± 0.011 g/cm2, 0.201 ± 0.017 g/cm2, 0.206 ± 0.021 g/cm2 vs. 0.168 ± 0.007 g/cm2), BMC (0.538 ± 0.036 g, 0.546 ± 0.039 g, 0.569 ± 0.048 g vs. 0.383 ± 0.022 g), serum CT level (30.42 ± 12.61 pg/ml, 31.35 ± 12.75 pg/ml, 30.83 ± 13.10 pg/ml vs. 26.76 ± 11.54 pg/ml) in the Yishen-Jianpi decoction groups of low-(n=10), medium-(n=10) and high-dose (n=9) were significantly increased (all P<0.05), while serum levels of sclerostin (86.32 ± 24.28 pg/ml, 87.65 ± 24.75 pg/ml, 86.82 ± 25.56 pg/ml vs. 105.78 ± 34.43 pg/ml) and PTH (9.36 ± 2.76 ng/dl, 9.76 ± 2.85 ng/dl, 9.84 ± 2.97 ng/dl vs. 11.52 ± 4.34 ng/dl) were significantly decreased (all P<0.05). Conclusions Yishen-Jianpi decoction can reduce serum sclerostin level, and has protective effects against osteoporosis in chronic atrophic gastritis in rats.

Objective To discuss the effect of atorvastatin to prevent the arterial restenosis after intracavitary therapy of patients with lower atherosclerotic occlusive (LASO).Methods One hundred and ten patients with LASO were randomly divided into the control group (n =55) and research group (n =55).All patients were given intraeavitary therapy (including balloon dilation, stent implantation and endarterectomy, stentimplantation and thromboetomy).The patients of the control group were given conventional anticoagulant therapy while the observation group were given atorvastatin 20 mg/d based same treatment of the control group for 6 months.The blood lipid, C-reactive protein (CRP), intima-media thickness (IMT) and the patency rate of lower limb artery of two group were observed and recorded before treatment and at 1 day,1 month,3 months and 6 months after treatment.Results The total cholesterol (preoperation, 1 month, 3 months and 6 months after operation were (4.90± 1.02) mmol/L, (4.07 ± 0.76) mmol/L, (3.82 ± 0.53) mmol/L and (3.64 ± 0.35) mmol/L respectively), CRP (preoperation, 1 month, 3 months and 6 months after operation were (31.60 ± 13.32) mg/L, (19.24±9.45) mg/L, (9.84 ± 6.43) mg/L and (6.34 ± 3.82) mg/L respectively) and IMT (preoperation, 1 month, 3 months and 6 months after operation were (1.08±0.25) mm, (1.02±0.27) mm, (0.92±0.22) mm and (0.81±0.16) mm respectively) of research group showed a downward trend,while the control group had no significant change, there were statistically significant differences among the research group (P＜0.05).Total cholesterol, IMT and CRP were significantly different among the patients of the research group at different time points (P ＜ 0.05), while there was no statistically significant difference in different times of patient(P＞0.05).There were no statistical significant about the patency rate at 1 day, 1 month,and 3 months after treatment between the two groups(P＞0.05),while the patency rate of research group at 6 months after treatment was obviously higher than that of control group (94.5％ (52/55) vs.74.5％ (41/55);x2 =7.637, P ＜0.05).Conclusion Atorvastatin can effectively reduce the blood lipid and CRP of patients with lower atherosclerotic occlusive and increase the patency rate,it is worth popularization and application.