Objective To investigate the spreading characteristics of plasmid-mediated resistance and the clones dissemination in multidrug resistant Klebsiella pneumoniae.Methods A total of 53 strains of multidrug resistant Klebsiella pneumoniae were successively collected from the First Affiliated Hospital,Zhejiang University School of Medicine during December 2009 and February 2012.Antimicrobial agents susceptibility was determined by Kirby-Bauer (K-B) method,and pulsed field gel electrophoresis (PFGE) was used to investigate the clonality of clinical isolates.Filter mating method was used for plasmid conjugation,and the relative molecular mass of the plasmid was determined using S1-PFGE assay.PCR amplification and sequencing were used to screen common antimicrobial resistance genes.Results Fiftythree clinical isolated Klebsiella pneumoniae strains were all resistant to penicillins,and their sensitive rates to piperacillin/tazobactam,cefoperazone/sulbactam were below 15％.More than 86％ strains were resistant to cephalosporins,and 60％-70％ strains were resistant to quinolones,sulfonamides and tetracyclines.About 50％ strains were resistant or intermediate sensitive to carbapenems.PFGE results did not support the evidence of clone dissemination.Resistant isolates harbored conjugant plasmid with 34 000-355 000 bp size,which encoded penicillins,cephalosporins,carbapenems or aminoglycoside resistant determinants,including CTX-M,TEM,KPC type β-1actamase genes and plasmid-mediated quinolone resistance gene qnr.Conclusions Multidrug resistance is prevalent in clinical Klebsiella pneumoniae isolates.Rapid prevalence of resistance is mainly determined by conjugant plasmid horizontal transfer rather than simple clone dissemination.

Objective To investigate the effects of triptolide on the expression of a series of proteins associated with interferon-γ (IFN-γ)signaling in HaCaT keratinocytes.Methods After pretreatment with difrerent dosages of triptolide(10-10-10-7 mol/L),HaCaT cells were stimulated by recombinant human IFN-γ(rhIFN-γ,500 U/mL)for various periods followed by the collection of cells.Then,total protein was extracted from these cells and subjected to Western blotting for the detection of expression of interferon-γ receptor α(IFN-γRα),phosphorylated Janus kinase 2(pJAK2)and suppressor of cytokine signaling (SOCS1).Results Triptolide at the concentrations of 10-8 mol/L and 10-7 mol/L significantly inhibited the IFN-γRα expression upregulated by rhIFN-γ(both P＜0.05).The expression of pJAK2 induced bv rhIFN-γ was also suppressed by triptolide at the concentrations of 10-9 moI/L and 10-8 mol/L(both P＜0.05).The inhibition of triptolide on IFN-γRα and pJAK2 expression was dose-dependent and the 50%inhibitory concentrations(IC50 value)were 1.37×10-8 mol/L and 2.83×10-9 mol/L,respectively.On the contrary,triptolide upregulated the expression of SOCS1 stimulated by rhIFN-γ at the concentrations of 10-10,10-9 and 10-8 mol/L(P＜0.05,0.05,0.01,respectively)with the 50%effective dosage(ED50 value)at 3.32 × 10-11 mol/L.Conclusions By inhibiting the expression of IFN-γRα as well as phosphorylation of JAK2 and upregulating the expression of SOCS1,triptolide inhibits the phosphorylation of STAT-1,resulting in the inhibition of genetic transcription of multiple inflammatory factors induced by IFN-γ signaling in HaCaT keratinocytes,and the inhibition probably contributes to the efficacy of triptolide in the treatment of IFN-γ-dependent inflammatory skin disorders,such as psoriasis.

Objective To analyse the clinical and therapeutic features as well as laboratory findings in bullous pemphigoid with non-bullous lesions as initial manifestation. Methods Clinical data on 34 cases of bullous pemphigoid with non-bullous lesions as initial manifestation were retrospectively analyzed. Results The male to female ratio was 1.83 :1, with a mean age of onset at 59.79±15.63 years. Before typical bullae appeared, patients presented with erythema, papules, papulovesicles' plaques" wheals, nodules,or erythema muitiforme-like lesions, with the most common lesions being erythematous papules and plaques (occumng in 35.29% of these patients). Conclusions Among these patients, nearly 1/3 displayed various skin lesions at the onset; simultaneous erythematous papules and plaques are the most common initial manifestation.

Objective: To investigate the prognosis of patients who receive neoadjuvant chemotherapy (NAC) for invasive micropapillary carcinoma (IMPC) of the breast using a propensity score matching (PSM) method and to analyze the effects of NAC. Methods: Clinical and pathological data of a total of 251 cases of IMPC of the breast were collected for this study, from January 2011 to March 2014 in Tianjin Medical University Cancer Institute and Hospital, of which the NAC group comprised 67 cases and the non-NAC group comprised 184 cases. Tumor sizes before and after NAC were compared in the NAC group. Prognostic differences were compared between the NAC group and non-NAC group before and after PSM balancing the baseline. Results: The mean value of the maximum dimensions significantly reduced from 5.0cm to 4.2cm in the NAC group after NAC (P=0.035), but there was no statistically significant difference in T stage changes (P=0.064). A total of 49 pairs of patients were matched after PSM, and differences in the baseline data of the paired group were not significant. Univariate survival analysis showed no significant difference in the recurrence-free survival (RFS) rate between the NAC group (77.6% vs. 89.2%) and non-NAC group (72.1% vs. 91.0%) before and after PSM (all P>0.05). The 5-year distant metastasis-free survival (DMFS) rates in the NAC group before and after PSM were 53.4% and 50.0%, respectively, which were both significantly lower than those in the non-NAC group 69.1%, 59.2% (all P<0.05), and multivariate survival analysis showed that undergoing NAC was an independent prognostic factor of DMFS after PSM. Conclusion: Breast IMPC is a special type of tumor that is not sensitive to chemotherapy. Although some tumors decrease after NAC, IMPC patients do not benefit from NAC in terms of RFS; NAC may even increase the risk of distant metastasis. Therefore, IMPC patients should undergo surgical treatment as soon as possible, and NAC is not recommended.

The epidemic of COVID-19 has become the topmost public health threat worldwide. The authors suggested that in addition to strengthening the organization and leadership of the abovementioned work, greater attention be paid to establishing and improving the prevention and control mechanism.Furthermore, special efforts should be given to the safety of the medical workers, by strengthening their infection monitoring and outbreak management. Medical workers in different work areas and positions should be placed under careful protection with due cleaning and disinfection measures. The protection during specimen collection, transportation and medical waste management should also be prioritized. Such special issues in the management of pediatric patients, as allocation of nurses, the screening and management of caregivers, the problem of breastfeeding, and the disinfection of children′s toys and diapers were discussed. This paper also put forward management suggestions for the outpatient department, isolation ward and other key departments, which aim to guide the prevention and control of COVID-19 nosocomial infection in the pediatric outpatient and ward.

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.