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.

Aim To study the diastolic effect and mechanism of farrerol on isolated pulmonary arteries of C57BL/6J mice.Methods After anesthesia,mouse lung tissue was quickly removed and placed into the 4 ℃ K-H buffer,pulmonary arteries were isolated under the microscope and cut into 2 mm long vascular rings for spare use.(1)The effect of farrerol on the resting tension of isolated mouse pulmonary arteries:in the resting state,the active mouse pul-monary artery rings were treated with different concentrations of farrerol(10-6,3×10-6,10-5,3×10-5 and 10-4 mol/L).(2)Farrerol relaxed mouse pulmonary artery experiment:pulmonary arteries were contracted using phenylephrine(PE,1 μmol/L)or KCl(60 mmol/L),and when the contraction reached the platform,different concentrations of farrerol(10-6,3×10-6,10-5,3×10-5 and 10-4 mol/L)was added.(3)Farrerol inhibited pulmonary artery contraction experi-ment:under conditions with or without the addition of farrerol,pulmonary arteries were contracted using different concen-trations of PE(10-9,3×10-9,10-8,3 × 10-8,10-7,3×10-7 and 10-6 mol/L)or KCl(20,30,40,60,80 and 120 mmol/L),and the pulmonary artery muscle tension was recorded.(4)Calcium free and recalcification experiments:under conditions with or without the addition of farrerol,the changes of isolated mouse pulmonary artery tension were meas-ured in the state of calcium free or recalcification { 2.5 mmol/L[Ca2+]ex }.(5)The relationship between farrerol in-duced relaxation of isolated mouse pulmonary arteries and potassium ion channels:firstly,60 mmol/L KCl solution was used to contract the mouse pulmonary arteries until the platform.Then,3 mmol/L aminopyridine(4-AP),2 mmol/L tet-raethylammonium(TEA),30 μmol/L BaCl2,and 10 μmol/L glibenclamide(Gli)were added and treated for 15 min.Subsequently,the pulmonary arteries were relaxed using a concentration gradient of farrerol.Results Farrerol had no significant effect on the mouse pulmonary arteries in the resting state,but had a concentration-dependent relaxing effect on the mouse pulmonary arteries pre-contracted with PE and KCl.While the pretreatment of 3×10-5 mol/L farrerol could sig-nificantly reduce the maximum contraction of mouse pulmonary arteries induced by PE and KCl(P＜0.01),as well as sig-nificantly reduce the contraction of mouse pulmonary arteries induced by KCl under calcium free or recalcification conditions(P＜0.01).Addition of the voltage-dependent potassium ion channel blocker 4-AP significantly reduced the maximum diastolic rate of mouse pulmonary arteries induced by farrerol(P＜0.01),while addition of the high conductivity calcium activated potassium ion channel blocker TEA,inward rectifying potassium ion channel blocker BaCl2,or ATP sensitive po-tassium ion channel blocker Gli had no significant effect on the vasodilation effect of farrerol(P＞0.05).Conclusion Farrerol has a relaxing effect on isolated mouse pulmonary arteries,and its mechanism may be related to open voltage-de-pendent potassium ion channels.

OBJECTIVE To investigate the inhibitory effects of Bruceine A(BA)on colon cancer and its underlying mechanisms.METHODS Human colon cancer HT-29 and HCT116 cells were treated with various concentrations of BA(0,1,2,5,10,20,40,80 μmol·L-1).Cell viability was assessed using the Cell Counting Kit-8(CCK-8).Flow cytometry,wound healing assays,and Transwell assays were employed to evaluate the effects of BA on cell apoptosis,cell cycle,invasion,and migration.Mo-lecular docking simulations were used to assess the binding of BA to GSK-3β protein,and Western blot analysis was used to examine protein expression related to the cell cycle,epithelial-mesenchymal transition,and the Wnt/β-catenin signaling pathway.An HT-29 cell subcutaneous xenograft mouse model was established.After tumor formation,mice were randomly divided into three groups(six mice per group):a blank group,a low-dose BA group(0.1 mg·kg-1),and a high-dose BA group(0.2 mg·kg-1).Mice were ad-ministered the drug for 19 d,then sacrificed,and tumor tissues were collected.Tumor volume changes over time were observed;Ki67 immunohistochemistry was used to assess cell proliferation in tumor tissues;Western blot analysis of Wnt/β-catenin signaling pathway protein expression was conducted.RESULTS Compared with the blank group,BA could significantly inhibit the proliferation of HT-29 and HCT116 cells,with IC50 values of 10.80 μmol·L-1 and 17.96 μmol·L-1,respectively.Flow cytometry results showed that BA significantly induced apoptosis of HT-29 cells(P<0.01,P<0.001),and arrested the cell cycle at the S phase,accompanied by de-creased expression of cycle-related proteins CDK2 and Cyclin A(P<0.05,P<0.01,P<0.001).BA inhibited cell migration and in-vasion ability(P<0.05,P<0.01,P<0.001),reduced the expression of EMT-related proteins Snail,Vimentin,and N-Cadherin(P<0.01,P<0.001),and upregulated the expression of E-Cadherin protein.In addition,BA inhibited the expression of β-catenin and p-GSK3β proteins.Wnt agonist LiCl could significantly antagonize the anti-colon cancer effect of BA;Wnt inhibitor XAV939 could enhance the anti-colon cancer effect of BA.In the in vivo experiment,compared with the blank group,the tumor volume of the low-dose and high-dose BA groups was significantly reduced(P<0.05,P<0.001).Immunohistochemistry results showed that compared with the blank group,the expression of Ki67 in tumor tissues of the low-dose and high-dose BA groups was significantly reduced(P<0.001).Western blot results further proved that BA inhibited the Wnt/β-catenin signaling pathway.CONCLUSION BA inhibits the viability,invasion,and migration of colon cancer HT-29 cells,induces apoptosis,and causes cell cycle arrest.Additionally,it significantly suppresses the growth of subcutaneous HT-29 cell xenografts in vivo,possibly related to the Wnt/β-catenin signaling pathway.

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.

Sleep-related hypermotor epilepsy （SHE） is a rare type of epilepsy with a prevalence rate of approximately 1.8/100 000. This disease mainly manifests as complex motor behaviors during non-rapid eye movement sleep， such as leg kicking， arm waving， and sitting up. Since such symptoms are similar to non-epileptic disorders such as night terrors and sleepwalking and abnormal discharges may not be observed on electroencephalography， the diagnosis of SHE is quite challenging. Currently， there is still a lack of evidence from large-scale randomized controlled studies to support pharmacological treatment strategies for SHE， and related data in China remain scarce. This article reports a case of SHE， in order to provide a clinical reference for the diagnosis and medication treatment of this disease.
Polysomnography

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.

This study was a single-center retrospective study, to investigate the correlation between the relative level of miR-200a in exfoliated cells of peritoneal dialysis (PD) effluent and clinical indicators of peritoneal function in PD patients. Clinical data of PD patients who underwent treatment in the Department of Nephrology, the First Affiliated Hospital of Nanchang University, from January 2024 to December 2024 were collected, and the relative level of miR-200a in exfoliated cells of PD effluent was assessed. Patients were divided into three groups according to dialysis duration (Group A:≤1 year; Group B:>1 to <5 years; Group C:≥5 years), and differences in clinical data among the groups were compared. The correlation between the relative level of miR-200a and serum albumin, serum calcium, serum phosphorus, serum creatinine, hemoglobin, the neutrophil/high-density lipoprotein cholesterol ratio, the monocyte/high-density lipoprotein cholesterol ratio, the lymphocyte/high-density lipoprotein cholesterol ratio, and 24-hour urine volume in PD patients was analyzed. The results showed that there were no statistically significant differences among the three groups in gender, age, creatinine clearance rate, or Kt/V (all P>0.05). However, statistically significant differences were found among the three groups in peritoneal transport type ( χ2=13.518, P=0.001) and ultrafiltration volume ( H=6.905, P=0.032). Based on the 4-hour PD effluent creatinine/blood creatinine in the peritoneal equilibration test, patients were divided into the low transporter/low average transporter group (L group) and the high transporter/high average transporter group (H group). A statistically significant difference in the relative level of miR-200a was observed between the two groups [11.70 (1.09, 20.49) vs. 0.73 (0.46, 1.98), t=4.545, P<0.001]. The relative level of miR-200a was positively correlated with ultrafiltration volume and 24-hour urine output ( r=0.328, P=0.030; r=0.516, P<0.001), and negatively correlated with dialysis vintage ( r=-0.496, P<0.001). These results indicate that miR-200a level in PD effluent may, to some extent, reflect patients' peritoneal membrane function.

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.