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 To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective To observe the protective effect of Yuebi Decoction on adriamycin(ADR)-induced mouse glomerular endothelial cells(MGEC),and to explore the possible mechanism of action.Methods MGEC were stimulated with ADR at a concentration of 1.25 μmol·L-1 for 12 h.MGEC were divided into five groups:normal group,model group,and Yuebi Decoction low,medium,and high dosage groups(5%,10%,and 20%of drug-containing serum);the viability of cells was detected by CCK-8 assay,the cell mobility was detected by Transwell assay.The relative expression levels of MGEC VCAM-1,Rac1,STAT3,and p-STAT3 were detected by Western blot.The expression of endothelial marker CD31,VCAM-1 and ICAM-1 was detected by immunofluorescence.Results Compared with the normal group,the endothelial cell migration rate was decreased in the model group(P<0.01),the protein expression levels of VCAM-1,ICAM-1,Rac1 and p-STAT 3 were significantly increased(P<0.05,P<0.01).The endothelial cell migration rate of the high-dose group of Yuebi Decoction was significantly increased compared with that of the model group(P<0.05).VCAM-1,ICAM-1,Rac1 and p-STAT3 protein expression levels of the drug-containing serum of Yuebi Decoction each group were significantly reduced(P<0.05,P<0.01).Conclusion Yuebi Decoction inhibited ADR-induced adhesion molecule expression in MGEC,alleviated endothelial injury,and improved endothelial cell migration rate.Its mechanism may be related to the inhibition of the Rac1/STAT3 signaling pathway.

Objective Sleep is an important physiological process for maintaining normal cognitive functions,but with the accelerated pace and increased work pressure in modern society,sleep deprivation has become a common phenomenon.It has been shown that sleep deprivation interferes with higher cognitive functions such as working memory,but the specific mechanism of its effect is still not completely clear.The present study aimed to systematically investigate the effects of 36 hours of sleep deprivation on the stages of the working memory processing chain and its neural mechanisms through behavioral and event-related potential(ERP)techniques.Methods Using a randomized controlled experimental design,48 healthy adult subjects were recruited and randomly assigned to sleep deprivation and control groups.All subjects completed a 2-back phonological working memory task,and behavioral data(response time and correctness)and ERP data(P2,N2,and P3 component wave amplitudes)were collected at 0 and 36 hours,respectively.The effects of sleep deprivation on working memory behavioral performance and neurophysiological indices were assessed by ANOVA.Results Behavioral results showed that the sleep deprivation group had a significantly longer response time after 36 hours,but no significant decrease in correctness,indicating a decrease in response efficiency but stable accuracy.ERP results showed that P2 amplitude did not change significantly before and after sleep deprivation,indicating that the early perception and categorization stages were limitedly affected by sleep deprivation;whereas,N2 and P3 amplitudes decreased significantly after sleep deprivation,reflecting that later cognitive processing such as conflict monitoring and resource allocation and other late cognitive processing were significantly disturbed.Conclusion Through ERP technology,this study uncovers the phased impact of 36-hour sleep deprivation on the working memory processing chain.The study found that early perceptual and categorization stages may be less susceptible to the effects of sleep deprivation,likely due to their relatively automatic processing and lower demand for cognitive resources.In contrast,during later stages of cognitive processing,particularly in higher-order functions such as conflict monitoring and resource allocation,sleep deprivation significantly impaired task performance efficiency by disrupting prefrontal cortex function.This finding deepens the understanding of the mechanisms underlying the effects of sleep deprivation and provides a scientific basis for cognitive intervention and management strategies in high-stress occupational groups.Future studies can further explore the long-term effects of sleep deprivation and its neural mechanisms by combining multimodal techniques.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

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 observe the effects of Yuebi Decoction on adriamycin-induced nephrotic syndrome(NS)and adhesion molecule levels in rats;To explore the possible mechanism of its inhibition of NS edema.Methods A NS rat model was established by a one-time tail vein injection of 6.5 mg/kg adriamycin.The rats were randomly divided into normal group,model group,prednisone group and Yuebi Decoction group.The prednisone group and Yuebi Decoction group were given 5 mg/kg prednisone and 22.2 g/kg Yuebi Decoction by gavage,respectively.The normal group and the model group were given an equal amount of normal saline by gavage,once a day for 2 consecutive weeks.The wet and dry weight ratios of skin and kidney were detected,24 hour urine total protein quantification(24 hUTP)and the contents of blood urea nitrogen(BUN),serum creatinine(SCr),total cholesterol(TC),albumin(ALB),hemoglobin(HB)were detected,HE and PAS staining was used to observe the morphology of renal tissue,ELISA was used to detect vascular cell adhesion molecule-1(VCAM-1)and intercellular adhesion molecule-1(ICAM-1)contents in renal tissue,the positive expressions of VCAM-1 and ICAM-1 were detected by immunohistochemistry,the expressions of VCAM-1,Rac1,signal transducer and activator of transcription 3(STAT3)and p-STAT3 proteins were detected by Western blot.Results Compared with the normal group,the wet dry weight ratio of the skin and kidney of the model group rats significantly increased(P<0.01),and the 24 hUTP,SCr,BUN and TC contents significantly increased(P<0.01),while the ALB and HB contents significantly decreased(P<0.01);with glomerular balloon atrophy,the renal tubules exhibit protein casts,inflammatory cell infiltration in renal interstitium,and significant increase in the contents of VCAM-1,ICAM-1 and protein expressions of VCAM-1,Rac1,p-STAT3 in renal tissue(P<0.01).Compared with the model group,the wet dry weight ratio of the skin and kidneys of rats in the prednisone group and Yuebi Decoction group was significantly reduced(P<0.05,P<0.01),and the 24 hUTP,SCr,BUN and TC were significantly reduced(P<0.01),while the contents of ALB and HB significantly increased(P<0.01);the infiltration of inflammatory cells in renal tissue was reduced,the protein casts decreased,and the contents of VCAM-1 and ICAM-1 in renal tissue,as well as the expressions of VCAM-1,Rac1 and p-STAT3 proteins significantly decreased(P<0.05,P<0.01).Conclusion Yuebi Decoction can alleviate edema,reduce urine protein,and improve capillary permeability in NS rats.Its mechanism is related to inhibiting the Rac1/STAT3 signaling pathway and reducing the expression of renal tissue adhesion molecules.

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.