ObjectiveTo investigate the role of interleukin （IL）-17A in acute inhalational pneumonia induced by the highly drug-resistant and hypervirulent Staphylococcus aureus strain USA300-R in mice. MethodsAn acute inhalational pneumonia model was established in mice using an aerosolized pulmonary delivery technique. RNA sequencing （RNA-seq） and enzyme-linked immunosorbent assay （ELISA） were employed to examine the expression dynamics of Il17a mRNA and IL-17A protein， respectively， in the lungs of infected mice. Il17a knockout （Il17a^-/-） mice were generated using CRISPR/Cas9 gene editing technology. The survival rate， body weight， bacterial load in lung tissue， and histopathological changes were compared between Il17a^-/- and wild-type （WT） mice following inhalational infection with USA300-R. Results12 hours after USA300-R infection， compared to pre-infection， the expression level of Il17a mRNA in lung tissue and the level of IL-17A protein in bronchoalveolar lavage fluid （BALF） increased by approximately 50-fold （P<0.01） and 6-fold （P<0.001）， respectively. Compared to WT mice， Il17a^-/- mice exhibited approximately 10-fold higher bacterial loads in lung tissue at both 12 and 24 hours post-infection （P<0.001， P<0.05）. However， they showed significantly attenuated lung histopathological injury， reduced alveolar wall thickening， markedly decreased neutrophil infiltration， and an approximately 50% improvement in survival rate （P<0.05）. ConclusionIn acute Staphylococcus aureus USA300-R inhalational pneumonia， IL-17A contributes to bacterial clearance by recruiting neutrophils； however， excessive neutrophil infiltration exacerbates pulmonary inflammation and injury， reduces survival rates， and represents a potential therapeutic target.

Objective To investigate predictive value of soluble growth stimulation-expressed gene 2 protein (sST2), cardiac troponin T (cTnT), and creatine kinase-myocardial band (CK-MB) for steroid resistance and prognosis in patients with immune checkpoint inhibitor-associated myocarditis (ICIAM). Methods A total of 28 patients with ICIAM were prospectively enrolled from March 2023 to February 2024 at Zhongshan Hospital, Fudan University. All participants were divided into the steroid-resistant ICIAM (srICIAM) group and the non-srICIAM group. Baseline serum levels of sST2, cTnT and CK-MB were detected prior to treatment initiation. ROC curve analysis was applied to evaluate the predictive value of these biomarkers, and Kaplan-Meier survival analysis was performed to explore the relationship between sST2 and all-cause mortality. Results Baseline sST2, cTnT, and CK-MB levels were significantly higher in the srICIAM group (n＝15) than in the non-srICIAM group (n＝13, P＜0.05). Combination of cTnT and sST2 improved predictive performance for srICIAM (AUC＝0.857, sensitivity 0.714, specificity 1.000). After 6 months of follow-up, the high sST2 group had a significantly higher all-cause mortality than the low sST2 group (P＝0.016). Conclusions The combination of sST2 and cTnT could effectively predict srICIAM, and elevated sST2 is associated with increased higher all-cause mortality in ICIAM patients, providing a basis for early risk stratification and treatment optimization.

In recent years,there has been a significant rise in the incidence of peripheral nerve injury(PNI),highlighting the urgent need for effective treatment strategies.The inflammation and pain hypersensitivity associated with PNI greatly diminish patients'quality of life.Although there are promising treatment approaches for nerve injury,the com-plex pathological mechanisms underlying neuropathic pain caused by PNI present significant challenges for clinical manage-ment.Extensive research has established that the development of neuropathic pain is closely linked to nerve conduction and related signaling molecules.Among these,P2X4 receptor(P2X4R),an ATP-dependent ion channel,is involved in nerve signal transmission and associated pathways-plays a crucial role in the progression of neuropathic pain.This article offers a comprehensive overview of the function and distribution of P2X4R,investigates its pathological mechanisms in PNI-induced neuropathic pain,and elucidates its relationship with peripheral neuropathic pain disorders.Through this explo-ration,we aim to provide valuable insights that could inform the development of novel clinical strategies for pain management.

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 understand the changing composition and antibiotic resistance of bacterial species in the clinical isolates from outpatient and emergency department(hereinafter referred to as outpatients)and inpatient children over time in various hospitals,and to provide laboratory evidence for rational antibiotic use.Methods The data on clinically isolated pathogenic bacteria and antimicrobial susceptibility of isolates from outpatients and inpatient children in the CHINET program from 2015 to 2021 were collected and analyzed.Results A total of 278 471 isolates were isolated from pediatric patients in the CHINET program from 2015 to 2021.About 17.1％of the strains were isolated from outpatients,primarily group A β-hemolytic Streptococcus,Escherichia coli,and Staphylococcus aureus.Most of the strains(82.9％)were isolated from inpatients,mainly SS.aureus,E.coli,and H.influenzae.The prevalence of methicillin-resistant S.aureus(MRSA)in outpatients(24.5％)was lower than that in inpatient children(31.5％).The MRSA isolates from outpatients showed lower resistance rates to the antibiotics tested than the strains isolated from inpatient children.The prevalence of vancomycin-resistant Enterococcus faecalis or E.faecium and penicillin-resistant S.pneumoniae was low in either outpatients or inpatient children.S.pneumoniae,β-hemolytic Streptococcus and S.viridans showed high resistance rates to erythromycin.The prevalence of erythromycin-resistant group A β-hemolytic Streptococcus was higher in outpatients than that in inpatient children.The prevalence of β-lactamase-producing H.influenzae showed an overall upward trend in children,but lower in outpatients(45.1％)than in inpatient children(59.4％).The prevalence of carbapenem-resistant Klebsiella pneumoniae(CRKpn),carbapenem-resistant Pseudomonas aeruginosa(CRPae)and carbapenem-resistant Acinetobacter baumannii(CRAba)was 14％,11.7％,47.8％in outpatients,but 24.2％,20.6％,and 52.8％in inpatient children,respectively.The prevalence of multidrug-resistant E.coli,K.pneumoniae,Proteus mirabilis,P.aeruginosa and A.baumannii strains was lower in outpatients than in inpatient children.The prevalence of fluoroquinolone-resistant E.coli,ESBLs-producing K.pneumoniae,ESBLs-producing P.mirabilis,carbapenem-resistant E.coli(CREco),CRKpn,and CRPae was lower in children in outpatients than in inpatient children,but the prevalence of CRAba in 2021 was higher than in inpatient children.Conclusions The distribution of clinical isolates from children is different between outpatients and inpatients.The prevalence of MRSA,ESBL,and CRO was higher in inpatient children than in outpatients.Antibiotics should be used rationally in clinical practice based on etiological diagnosis and antimicrobial susceptibility test results.Ongoing antimicrobial resistance surveillance and prevention and control of hospital infections are crucial to curbing bacterial resistance.

Objective To investigate the changing antibiotic resistance profiles of E.coli isolated from patients in the 52 hospitals participating in the CHINET program from 2015 to 2021.Methods Antimicrobial susceptibility was tested for clinical isolates of E.coli according to the unified protocol of CHINET program.WHONET 5.6 and SPSS 20.0 software were used for data analysis.Results Atotal of 289 760 nonduplicate clinical strains ofE.coli were isolated from 2015 to 2021,mainly from urine samples(44.7±3.2)％.The proportion of E.coli strains isolated from urine samples was higher in females than in males(59.0％vs 29.5％).The proportion of E.coli strains isolated from respiratory tract and cerebrospinal fluid samples was significantly higher in children than in adults(16.7％vs 7.8％,0.8％vs 0.1％,both P＜0.05).The isolates from internal medicine department accounted for the largest proportion(28.9±2.8)％with an increasing trend over years.Overall,the prevalence of ESBLs-producing E.coli and carbapenem resistant E.coli(CREco)was 55.9％and 1.8％,respectively during the 7-year period.The prevalence of ESBLs-producing E.coli was the highest in tertiary hospitals each year from 2015 to 2021 compared to secondary hospitals.The prevalence of CREco was higher in children's hospitals compared to secondary and tertiary hospitals each year from 2015 to 2021.The prevalence of ESBLs-producing E.coli in tertiary hospitals and children's hospitals and the prevalence of CREco in children's hospitals showed a decreasing trend over the 7-year period.The prevalence of CREco in secondary and tertiary hospitals increased slowly.Antibiotic resistance rates changed slowly from 2015 to 2021.Carbapenem drugs(imipenem,meropenem)were the most active drugs amongβ-lactams against E.coli(resistance rate≤2.1％).The resistance rates of E.coli to β-lactam/β-lactam inhibitor combinations(piperacillin-tazobactam,cefoperazone-sulbactam),aminoglycosides(amikacin),nitrofurantoin and fosfomycin(for urinary isolates only)were all less than 10％.The resistance rate of E.coli strains to antibiotics varied with the level of hospitals and the departments where the strains were isolated,especially for cefazolin and ciprofloxacin,to which the resistance rate of E.coli strains from children in non-ICU departments was significantly lower than that of the strains isolated from other departments(P＜0.05).The E.coli isolates from ICU showed higher resistance rate to most antimicrobial agents tested(excluding tigecycline)than the strains isolated from other departments.The E.coli strains isolated from tertiary hospitals showed higher resistance rates to the antimicrobial agents tested(excluding tigecycline,polymyxin B,cefepime and carbapenems)than the strains from secondary hospitals and children's hospitals.Conclusions E.coli is an important pathogen causing clinical infection.More than half of the clinical isolates produced ESBL.The prevalence of CREco is increasing in secondary and tertiary hospitals over the 7-year period even though the overall prevalence is still low.This is an issue of concern.

Objective To explore the molecular mechanisms by which cytochrome P4502C regulates ferroptosis in hu-man retinal microvascular endothelial cells(hRMECs)under high-glucose conditions.Methods Human retinal microvas-cular endothelial cells(hRMECs)were cultured in vitro and divided into six groups:the NG group(cells cultured in ser-um-free DMEM medium containing 5.5 mmol·L-1 glucose);the NG+fenofibrate group(10 μmol·L-1 fenofibrate added to the NG group);the NG+rifampicin group(10 μmol·L-1 rifampicin added to the NG group);the HG group(cells cul-tured in serum-free DMEM medium containing 25.5 mmol·L-1 glucose);the HG+fenofibrate group(10 μmol·L-1 feno-fibrate added to the HG group);and the HG+rifampicin group(10 μmol·L-1 rifampicin added to the HG group).After 48 hours of culture,subsequent experiments were conducted.Cell viability was assessed using the CCK-8 assay.The levels of malondialdehyde(MDA)and iron content in hRMECs were measured using commercial assay kits.The relative fluores-cence intensity of Liperfluo was quantified by flow cytometry.The mRNA expression levels of glutathione peroxidase 4(GPX4),cytochrome P4502C,and acyl-CoA synthetase long-chain family member 4(ACSL4)in hRMECs were analyzed using real-time quantitative PCR.The protein expression levels of GPX4,cytochrome P4502C,and ACSL4 in hRMECs were evaluated using Western blot analysis.Results Optimal concentration analysis showed that the 10 μmnol·L-1 fenofibrate group had the highest cell viability compared to the HG group(P＜0.05),while the 10 μmol·L-1 rifampicin group had the lowest cell viability(P＜0.05).Thus,10 μmol·L-1 was selected as the optimal concentration for both fenofibrate and rif-ampicin for subsequent experiments.Cell viability in the NG,NG+fenofibrate,NG+rifampicin,HG,HG+fenofibrate,and HG+rifampicin groups was(100.00±7.85)％,(102.15±9.07)％,(69.97±4.22)％,(61.74±6.13)％,(83.64±7.58)％,and(56.96±5.34)％,respectively.Compared with the NG group,the HG group had significantly lower cell via-bility(P＜0.05).Compared with the HG group,the HG+fenofibrate group had significantly higher cell viability(P＜0.05).Compared with the NG group,the HG group had higher levels of MDA,iron content,and Liperfluo relative fluores-cence intensity(all P＜0.05).Compared with the HG group,the HG+fenofibrate group had lower levels of MDA,iron content,and Liperfluo relative fluorescence intensity(all P＜0.05);the HG+rifampicin group had higher levels of these parameters(all P＜0.05).Compared with the NG group,the HG group had higher mRNA and protein expression levels of cytochrome P4502C and ACSL4,but lower levels of GPX4 mRNA and protein(all P＜0.05).Compared with the HG group,the HG+fenofibrate group had lower mRNA and protein expression levels of cytochrome P4502C and ACSL4,but higher lev-els of GPX4 mRNA and protein(all P＜0.05);the HG+rifampicin group had higher mRNA and protein expression levels of cytochrome P4502C and ACSL4,but lower levels of GPX4 mRNA and protein(all P＜0.05).Conclusion Cytochrome P4502C can promote ferroptosis of hRMECs under high-glucose conditions by regulating the GPX4/ACSL4 signaling axis;in-hibition of cytochrome P4502C expression can exert a protective effect on DR;modulation of the expression levels or bal-ance of the key factors GPX4 and ACSL4 in this pathway may hold promise as a potential strategy to slow the progression of DR.

Objective:To explore the improvement of the quality standard of Ginkgo Leaf Extract and Dipyridamole Injection and conduct safety tests including abnormal toxicity test,allergic reaction test,hemolysis and coagulation test.Methods:Ginkgo Leaf Extract and Dipyridamole Injection from 3 different manufactures(A,B and C)were tested respectively through abnormal toxicity test and acute toxicity test in mice,active systemic anaphylaxis test in guinea pigs and hemolysis test in vitro.Five mice were used in each batch for abnormal toxicity test according to the abnormal toxicity test method in general notice of the Chinese Pharmacopoeia 2020 Volume Ⅳ(1141),and 50 mice were selected in each batch for acute toxicity test to determine the median lethal dose(LD50)or maximum tol-erable dose(MTD)of Ginkgo Leaf Extract and Dipyridamole Injection,which were used to establish the method of abnormal toxicity experiment.The anaphylaxis of Ginkgo Leaf Extract and Dipyridamole Injection was evaluated by active systemic anaphylaxis test in guinea pigs,which was used to establish the method of allergic test.The hemoly-sis test of Ginkgo Leaf Extract and Dipyridamole Injection was studied by conventional tube method in vitro(macro-scopic observation)and improved hemolysis method in vitro(spectrophotometric method),which were used to establish the method of hemolysis and coagulation test.Results:① In manufacture A,the results of abnormal toxicity test were showed that LD50 was20.8 mL·kg-1and MTD was 16.5 mL·kg-1.No death or abnormal reac-tions were observed in mice tested for abnormal toxicity of 2 manufactures(B and C),and MTD was 50 and 40 mL·kg-1,respectively.②The no-observed-adverse-effect dose of Ginkgo Leaf Extract and Dipyridamole Injec-tion from 3 manufactures to guinea pig intravenous was 0.83 mL·kg-1,and no allergic reaction symptoms were observed when Ginkgo Leaf Extract and Dipyridamole Injection was diluted 4 times to challenge the sensitized guinea pigs(equivalent to human clinical dosage).③Differences were observed in the hemolytic effects of Ginkgo Leaf Extract and Dipyridamole Injection from 3 manufactures,but no obvious hemolytic reaction occurred when it was diluted 1.2 times(equivalent to 5%of the maximum clinical concentration).Conclusion:It is recommended to add abnormal toxicity test,allergic reaction test,hemolysis and coagulation test in the quality standard of Ginkgo Leaf Extract and Dipyridamole Injection as safety test items to control the risk.The proposed method is diluting Ginkgo Leaf Extract and Dipyridamole Injection by 5 times,4 times and 1.2 times to perform abnormal toxicity test,allergic reaction test,hemolysis test and coagulation test respectively.