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 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 investigate the clinical efficacy and safety of facilitated percutaneous coronary intervention(PCI)with half-dose recombinant staphylokinase(r-SAK)in patients with ST-segment elevation myocardial infarction(STEMI)who are expected to undergo PCI within 120 minutes.Methods From October 2021 to August 2022,a total of 200 STEMI patients in eight centers were included and randomly assigned in a 1﹕1 ratio to either r-SAK group or control group.Patients received loading doses of aspirin and ticagrelor and intravenous heparin and were randomized to receive an intravenous bolus of either 5 mg r-SAK or normal saline prior to PCI.The outcomes were set as ST-segment resolution(STR)at 60-90 minutes after PCI,the proportion and transition of pathological Q waves on the 5th day after PCI,and the proportion of high-sensitivity cardiac troponin T(hs-cTnT)peaking within 12 hours of onset.The safety outcome was major bleeding events defined as Bleeding Academic Research Consortium(BARC)≥type 3 bleeding during hospitalization.Results Compared with the control group,the r-SAK group had a higher proportion of STR≥70%within 60-90 minutes after PCI(58.3%vs.40.3%,P=0.009);a lower proportion of pathological Q waves(59.1%vs.74.1%,P=0.040);a lower rate of Q wave progression(14.8%vs.43.2%,P＜0.001);a higher rate of Q wave disappearance(12.5%vs.3.7%,P=0.027);and a higher proportion of hs-cTnT peaking within 12 hours of symptom onset[31/40(77.5%)vs.17/33(51.5%),P=0.027].Regarding the safety outcome,no significant difference in BARC≥type 3 bleeding was found between the two groups during hospitalization(P＞0.05).Conclusions For STEMI patients who were expected to undergo primary PCI within 120 minutes of symptom onset,the facilitated PCI with half-dose r-SAK significantly increased the proportion of STR≥70%at 60-90 minutes after PCI,reduced the formation of pathological Q waves,and shortened the time to peak hs-cTnT,without increasing the risk of bleeding,which should be an alternative reperfusion strategy worthy of further study.

AIM:This study aims to design pH/near-infrared(NIR)dual-responsive metal-organic framework composite nanoparticles co-loaded with indocyanine green(ICG)and sphingosine kinase 1(SphK1)siRNA(siSphK1),and to evaluate their anticancer efficacy against non-small-cell lung cancer A549 cells.METHODS:The ZIF-8 nanopar-ticles were synthesized and loaded with ICG and siSphK1 to prepare ZIF-8@ICG@siSphK1 nanoparticles.Their morpholo-gy,particle size,surface charge,and crystalline structure were characterized through transmission electron microscopy,dynamic light scattering,and X-ray diffraction.Stability,siSphK1 encapsulation and protection,and pH/NIR response were assessed.The gene silencing efficacy and anticancer activity in A549 cells were evaluated using Western blot,RT-qPCR,MTT assay,flow cytometry,and reactive oxygen species(ROS)fluorescence staining.RESULTS:The ZIF-8@ICG@siSphK1 nanoparticles exhibited a typical polyhedral structure with an average particle size of(76.8±0.9)nm and a ζ potential of(9.2±0.1)mV.The nanoparticles effectively encapsulated siSphK1,protecting it from RNase degra-dation,and demonstrated excellent NIR responsiveness with a photothermal conversion efficiency of 39.7%.After 10 h of 808 nm laser irradiation,siRNA cumulative release was significantly higher at pH 5.5 compared with pH 7.4.In A549 cells,the nanoparticles efficiently delivered siSphK1 under NIR irradiation,significantly down-regulated SphK1 gene ex-pression,inhibited cell proliferation,induced apoptosis,and increased intracellular ROS levels.CONCLUSION:The ZIF-8@ICG@siSphK1 nanoparticles effectively induce cytotoxic effects against A549 cells through gene silencing and pho-tothermal therapy.

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.

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 explore the effect of Lactobacillus reuteri on testicular injury in mice exposed to neonicotinoid insec-ticides(NNI).Methods:Fifteen C57BL/6 male mice were randomly divided into control group(CTRI.group),exposure group(NNI group)and Lactobacillus intervention group(NNI-L group).The mice in CTRL group were given 0.02ml/g of 0.5％carboxym-ethyl cellulose sodium solution by gavage for 14 days.The mice in NNI group were given 0.02 ml/g of NNI mixture by gavage for 14 days.The mice in NNI-L group were given 0.02 ml/g of NNI mixture by gavage and 5 × 108cfu/ml of Lactobacillus reuteri powder so-lution for 14 days.Then,the histomorphology and function of testicle were evaluated by hematoxylin-eosin staining,immunofluores-cence staining and RNA sequencing.Results:Compared with CTRL group,the thickness of testicular seminiferous epithelium in the NNI group was significantly thinner.And the decline in the number of spermatogenic cells and sperm was observed.And the expression of spermatogonial stem cell marker UCHL1 was down-regulated which was significantly improved in NNI-L group compared with the NNI group.The abnormal expressions of hormone and sperm methylation related genes in testis of NNI group were detected by RNA sequen-cing,with significant down-regulation being found in NPFF and IGF2.While the expression of HSD3B8 was significantly up-regulated.The abnormal expression of these genes could be significantly improved after oral administration of Lactobacillus reuteri.Conclusion:Testicular spermatogenesis and endocrine function can be damaged by NNI exposure.And oral administration of Lactoba-cillus reuteri protects testis from the adverse effects of NNI toxicity.

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.