Objective To summarize the changing prevalence of carbapenem resistance in Enterobacterales based on the data of CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021 for improving antimicrobial treatment in clinical practice.Methods Antimicrobial susceptibility testing was performed using a commercial automated susceptibility testing system according to the unified CHINET protocol.The results were interpreted according to the breakpoints of the Clinical & Laboratory Standards Institute(CLSI)M100 31st ed in 2021.Results Over the seven-year period(2015-2021),the overall prevalence of carbapenem-resistant Enterobacterales(CRE)was 9.43％(62 342/661 235).The prevalence of CRE strains in Klebsiella pneumoniae,Citrobacter freundii,and Enterobacter cloacae was 22.38％,9.73％,and 8.47％,respectively.The prevalence of CRE strains in Escherichia coli was 1.99％.A few CRE strains were also identified in Salmonella and Shigella.The CRE strains were mainly isolated from respiratory specimens(44.23±2.80)％,followed by blood(20.88±3.40)％and urine(18.40±3.45)％.Intensive care units(ICUs)were the major source of the CRE strains(27.43±5.20)％.CRE strains were resistant to all the β-lactam antibiotics tested and most non-β-lactam antimicrobial agents.The CRE strains were relatively susceptible to tigecycline and polymyxins with low resistance rates.Conclusions The prevalence of CRE strains was increasing from 2015 to 2021.CRE strains were highly resistant to most of the antibacterial drugs used in clinical practice.Clinicians should prescribe antimicrobial agents rationally.Hospitals should strengthen antibiotic stewardship in key clinical settings such as ICUs,and take effective infection control measures to curb CRE outbreak and epidemic in hospitals.

Objective To characterize the changing species distribution and antibiotic resistance profiles of respiratory isolates in hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program from 2015 to 2021.Methods Commercial automated antimicrobial susceptibility testing systems and disk diffusion method were used to test the susceptibility of respiratory bacterial isolates to antimicrobial agents following the standardized technical protocol established by the CHINET program.Results A total of 589 746 respiratory isolates were collected from 2015 to 2021.Overall,82.6％of the isolates were Gram-negative bacteria and 17.4％were Gram-positive bacteria.The bacterial isolates from outpatients and inpatients accounted for(6.0±0.9)％and(94.0±0.1)％,respectively.The top microorganisms were Klebsiella spp.,Acinetobacter spp.,Pseudomonas aeruginosa,Staphylococcus aureus,Haemophilus spp.,Stenotrophomonas maltophilia,Escherichia coli,and Streptococcus pneumoniae.Each microorganism was isolated from significantly more males than from females(P＜0.05).The overall prevalence of methicillin-resistant S.aureus(MRSA)was 39.9％.The prevalence of penicillin-resistant S.pneumoniae was 1.4％.The prevalence of extended-spectrum β-lactamase(ESBL)-producing E.coli and K.pneumoniae was 67.8％and 41.3％,respectively.The overall prevalence of carbapenem-resistant E.coli,K.pneumoniae,Enterobacter cloacae,Pseudomonas aeruginosa,and Acinetobacter baumannii was 3.7％,20.8％,9.4％,29.8％,and 73.3％,respectively.The prevalence of β-lactamase was 96.1％in Moraxella catarrhalis and 60.0％in Haemophilus influenzae.The H.influenzae isolates from children(＜18 years)showed significantly higher resistance rates to β-lactam antibiotics than the isolates from adults(P＜0.05).Conclusions Gram-negative bacteria are still predominant in respiratory isolates associated with serious antibiotic resistance.Antimicrobial resistance surveillance should be strengthened in clinical practice to support accurate etiological diagnosis and appropriate antimicrobial therapy based on antimicrobial susceptibility testing results.

Objective:To investigate the correlation between rectal colonization of carbapenem resistant Klebsiella pneumoniae（CRKP）and bloodstream infections（BSI）using molecular epidemiological analysis. Methods:Patients admitted to the Intensive Care Unit（ICU），Hematology Department，and Neurosurgery Department of the First Hospital of Jiaxing from January 2022 to December 2024，were enrolled. Rectal CRKP colonization screening was performed for all participants，with concurrent monitoring for BSI.Whole genome sequencing of CRKP strains in the intestine and blood flow of patients with CRKP rectal colonization and CRKP-BSI was performed using the Illumina NovaSeq PE150 sequencing platform，and samples were genotyped based on the PubMLST database. MLST 2.0 was applied for multi site sequence typing，VFDB online database was used to analyze virulence genes，ResFinder was used to analyze resistance genes，and whole genome sequences were imported into BioNumerics software for core genome multi site sequence typing and clustering analysis. Using the BacWGSTdb database to construct a phylogenetic tree based on genomic SNPs，and the homology between CRKP rectal fixed plants and corresponding BSI-CRKP infected plants were analyzed.Results:A total of 772 patients were included，including 78 cases with positive results in rectal CRKP colonization screening（10.1%）and 694 cases without rectal CRKP colonization（89.9%）. The CRKP-BSI rate in rectal CRKP colonization patients was significantly higher than that in non-CRKP colonization patients［19.2%（15/78） vs. 5.5%（38/694）， χ2=20.749， P<0.001］. Analysis of CRKP rectal colonization strains and bloodstream infection strains in 15 patients with CRKP rectal implantation and CRKP-BSI revealed that ST11 type was the main strain（ n=10），followed by ST37 type（ n=3），with all carrying multiple β-lactam and carbapenem producing enzyme resistance genes.The distribution of virulence genes showed that CRKP strains carried multiple virulence genes，with iroE being ubiquitous，followed by iucA/ B/ C/ D， rmpA2，rmpA，and iroN. All ST11-type CRKP strains exhibited hypervirulent characteristics. Capsular serotyping analysis showed that the predominant type of CRKP colonization and infection strains was KL64. The results of cgMLST and SNP clustering analysis showed that CRKP rectal fixed plants exhibited homology with blood flow infected plants. Moreover，two clusters of CRKP rectal colonization strains with significant homology were found to cluster together among 15 patients. Conclusions:Rectal colonization of CRKP is an important risk factor for the occurrence of BSI-CRKP in hospitals，and ST11 hypervirulent CRKP is the main type. It is recommended to screen high-risk patients for CRKP to reduce the risk of BSI-CRKP.

Objective:To observe the effect of sodium cantharidate assisted bevacizumab in the treatment of advanced non-small cell lung cancer patients.Methods:A total of 120 patients with advanced lung adenocarcinoma from January 2021 to December 2023 were divided into two groups,namely the experimental group and the matched group,each consisting of 60 cases.All patients were treated with AP(cisplatin+pemetrexed)chemotherapy,and bevacizumab(7.5 mg/kg)was administered intravenously at the same time as chemotherapy in the matched group,while sodium bengalate(0.5 mg)was added intravenously in the experimental group on the basis of the matched group,and the patients in the two groups were compared with each other in terms of the clinical efficacy of the two groups in a cycle of 21 d,and the changes in the indicators of the immune function,symptoms and scores of adverse reactions were also compared before and after the 4 consecutive cycles of treatment.After 4 consecutive cycles of treatment,we compared the clinical efficacy,immune function indexes,symptoms,and the incidence of adverse reactions.Results:There was no difference in disease control rate(P＞0.05),and the objective response rate was higher than the matched group(P＜0.05);Pretherapy,tthe levels of natural killer(NK)cells,CD4+/CD8+,immunoglobulin(Ig)G and IgA were different between the test and matched group(P＞0.05).Post-treatment,the levels of NK cells,CD4+/CD8+,IgG,and IgA in the experimental group increased,while there was no significant change in the matched group.The experimental group was higher than the matched group(P＜0.05);Pretherapy,there was no difference in VAS and BFI scores between the experimental group and the matched group(P＞0.05).Post-treatment,the scores of the Simplified Fatigue Scale(BFI)and Visual Analog Scale(VAS)in both groups decreased,and the experimental group was lower than the matched group(P＜0.05);The incidence of grade Ⅰ-Ⅱ gastrointestinal reactions,liver and kidney dysfunction,bone marrow suppression,leukopenia,and grade Ⅲ-Ⅳ bone marrow suppression in the experimental group were all lower than those in the matched group(P＜0.05).Conclusion:Sodium cantharidate assisted bevacizumab therapy has a significant effect on non-small cell lung cancer.Compared with single chemotherapy combined with bevacizumab,it can improve the objective remission rate of patients,improve their immune function level,alleviate pain and cancer-related fatigue symptoms,and assist in reducing the incidence of adverse reactions caused by bevacizumab and chemotherapy.

Objective To investigate the distribution and antimicrobial resistance profiles of common pathogens isolated from cerebrospinal fluid(CSF)in CHINET program from 2015 to 2021.Methods The bacterial strains isolated from CSF were identified in accordance with clinical microbiology practice standards.Antimicrobial susceptibility test was conducted using Kirby-Bauer method and automated systems per the unified CHINET protocol.Results A total of 14 014 bacterial strains were isolated from CSF samples from 2015 to 2021,including the strains isolated from inpatients(95.3％)and from outpatient and emergency care patients(4.7％).Overall,19.6％of the isolates were from children and 80.4％were from adults.Gram-positive and Gram-negative bacteria accounted for 68.0％and 32.0％,respectively.Coagulase negative Staphylococcus accounted for 73.0％of the total Gram-positive bacterial isolates.The prevalence of MRSA was 38.2％in children and 45.6％in adults.The prevalence of MRCNS was 67.6％in adults and 69.5％in children.A small number of vancomycin-resistant Enterococcus faecium(2.2％)and linezolid-resistant Enterococcus faecalis(3.1％)were isolated from adult patients.The resistance rates of Escherichia coli and Klebsiella pneumoniae to ceftriaxone were 52.2％and 76.4％in children,70.5％and 63.5％in adults.The prevalence of carbapenem-resistant E.coli and K.pneumoniae(CRKP)was 1.3％and 47.7％in children,6.4％and 47.9％in adults.The prevalence of carbapenem-resistant Acinetobacter baumannii(CRAB)and Pseudomonas aeruginosa(CRPA)was 74.0％and 37.1％in children,81.7％and 39.9％in adults.Conclusions The data derived from antimicrobial resistance surveillance are crucial for clinicians to make evidence-based decisions regarding antibiotic therapy.Attention should be paid to the Gram-negative bacteria,especially CRKP and CRAB in central nervous system(CNS)infections.Ongoing antimicrobial resistance surveillance is helpful for optimizing antibiotic use in CNS infections.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

Lentiviral vectors(LVs)are key gene delivery tools for integrating target genes into the host genome,but they may also pose risks of insertional mutagenesis.The vector copy number(VCN)in cells is critical for determining the safety of gene modification.However,the reliability and accuracy of its quantification process are influenced by multiple factors.Developing cell reference materials with specific vector copy numbers represents a viable approach to enhance the reliability and consistency of measurement results,enabling quality control of the quantification process and traceability of outcomes.However,the preparation of such reference materials faces challenges in cell sample design,preparation protocols,and advanced quantification techniques.In this study,T lymphocyte cell line Jurkat-based reference materials with LV gene copy numbers of 1 and 2 copy/cell were developed.A high-precision duplex digital polymerase chain reaction(dPCR)method was established to quantify the LV gene and endogenous genes simultaneously.Additionally,the results of dPCR were cross-validated through next-generation sequencing and flow cytometric analysis.Ultimately,confocal microscopy characterization results showed that the developed cell reference materials had intact morphology.The quantification result of VCN-1 was(1.07±0.11)copy/cell,and that of VCN-2 was(2.09±0.21)copy/cell.These cell reference materials demonstrated compliance with stability and homogeneity requirements,and could be applied for quality control throughout the VCN measurement workflow and metrological traceability,improving the accuracy,comparability,and validity of copy number measurements.

Objective:To analyze the multimorbidity trends and influencing factors of internet addiction and depressive symptoms among middle school students in Zhejiang Province.Methods:From 2018 to 2023, a multistage stratified random cluster sampling method was used to select middle school students aged 12 to 18 in Zhejiang Province. Internet addiction and depression status were measured by the Internet Addiction Scale and the Center for Epidemiologic Studies Depression Scale. When both symptoms were present, it was defined as multimorbidity.The multivariate logistic regression model was used to analyze the influencing factors of multimorbidity among middle school students, and a trend Chi-square test was used to analyze the changing trends of internet addiction, depression and multimorbidity prevalence. Results:A total of 193 505 students were included in the study. From 2018 to 2023, the prevalence of multimorbidity of internet addiction and depressive symptoms among middle school students ranged from 2.7% to 3.5%. The prevalence of internet addiction ranged from 4.7% to 6.0%, while the prevalence of depressive symptoms ranged from 18.7% to 25.1%. Multivariate logistic regression showed that boarding students ( OR=1.34 , 95% CI: 1.26-1.42), low-frequency ( OR=1.59, 95% CI: 1.46-1.73), and high-frequency sugary drink consumption ( OR=3.91, 95% CI: 3.55-4.31) increased the risk of multimorbidity among middle school students. In contrast, higher frequencies of moderate-to-high-intensity exercise (medium: OR=0.54, 95% CI: 0.50-0.58; high: OR=0.49, 95% CI: 0.44-0.55) and sufficient sleep ( OR=0.52, 95% CI: 0.49-0.56) were protective factors. From 2018 to 2023, there was no significant change in the trend of multimorbidity prevalence among middle school students ( χ2trend=3.82, P=0.051). The prevalence of internet addiction showed an upward trend ( χ2trend=20.54, P<0.001), while depressive symptoms showed a downward trend ( χ2trend=181.41, P<0.001). Conclusion:The prevalence of internet addiction and depression symptoms among middle school students in Zhejiang Province remains stable from 2018 to 2023. The prevalence of internet addiction shows an upward trend, while the prevalence of depression symptoms shows a downward trend. The risk of multimorbidity is related to students′ boarding, consumption of sugary drinks, lack of exercise, and insufficient sleep.

Objective To compare the therapeutic efficacy of a self-locking zero-notch interbody fusion device for long-segment cervical spondylosis in elderly patients with traditional titanium plate combined with interbody fusion device.Methods From Jan 2019 to Jan 2021,elderly patients(>60 years)with 3-4 segments(C3-C7)radiculopathy,myelopathy,or mixed-type cervical spondylosis underwent anterior cervical discectomy and fusion(ACDF)using a zero-notch interbody fusion device(Group A,n=24)and ACDF using a titanium plate combined with an interbody fusion device(Group B,n=18).We recorded the surgery duration,blood loss,incision length and hospital stay,measure preoperative and postoperative intervertebral height,functional segment height and cervical lordosis,and also observe treatment outcomes and postoperative complications between the two groups.Results There were no statistically significant differences between the two groups in terms of gender,age,Japanese Orthopaedic Association(JOA)score,visual analogue scale(VAS)of upper limb,Neck Disability Index(NDI),preoperative intervertebral height,functional segment height and cervical lordosis.Blood loss,surgery time and hospital stay were similar in both groups,but Group A had shorter incision length(P<0.01)compared with Group B.There were no significant differences between the two groups in JOA scores,upper limb VAS and postoperative NDI,and even in postoperative intervertebral height,functional segment height and cervical lordosis recovery.Conclusion The zero-notch interbody fusion device is effective for treating long-segment cervical spondylosis.Compared with the traditional titanium plate combined with an interbody fusion device,it can avoid postoperative dysphagia with smaller incision and shorter surgery time,which makes it more suitable for elderly patients.