OBJECTIVE To investigate the apoptosis-inducing effect of esculetin （Esc） on acute myeloid leukemia （AML） HL-60 cells by regulating the protein kinase B （AKT）/S-phase kinase-associated protein 2 （SKP2）/MutT homolog 1 （MTH1） pathway. METHODS AML HL-60 cells were randomly divided into control group （routine culture）， Esc low-concentration group （L-Esc group， 25 μmol/L Esc）， Esc medium-concentration group （M-Esc group， 50 μmol/L Esc）， Esc high-concentration group （H-Esc group， 100 μmol/L Esc）， and high-concentration of Esc+ SC79 （AKT agonist） group （100 μmol/L Esc+5 μmol/L SC79）. Cell proliferation in each group was detected by MTT assay and colony formation assay. The level of reactive oxygen species （ROS） in cells was measured by using the CM-H2DCFDA fluorescent probe. Cell apoptosis was analyzed by flow cytometry. Western blot assay was performed to detect the expression levels of apoptosis-related proteins [B-cell lymphoma 2 （Bcl-2）， Bcl-2-associated X protein （Bax）， cleaved caspase-3]， AKT/SKP2/MTH1 pathway-related proteins （p-AKT， AKT， SKP2， MTH1）， along with the upstream and downstream proteins of AKT phosphatidylinositol 3-kinase （PI3K）， cyclin-dependent kinase inhibitor 1 （P21） and cyclin-dependent kinase inhibitor 1B （P27）. RESULTS Compared with control group， the cell viability， colony number， and the phosphorylation levels of AKT and PI3K proteins as well as protein expressions of SKP2， MTH1 and Bcl-2 were significantly decreased （P＜0.05）， while ROS level， apoptosis rate， and the expression levels of Bax， cleaved caspase-3， P21 and P27 proteins were significantly increased （P＜0.05）. Moreover， the effects of Esc exhibited concentration-dependence （P＜0.05）. Compared with H-Esc group， above indexes of high-concentration of Esc+ SC79 group were reversed significantly （P＜0.05）. CONCLUSIONS Esc may promote massive ROS production and induce activation of apoptosis in HL-60 cells by inhibiting the AKT/SKP2/MTH1 pathway， thus inhibiting the proliferation of HL-60 cells.

ObjectiveTo investigate the effect and mechanism of transplantation of human umbilical cord mesenchymal stem cell （hUC-MSC） with overexpression of the Numb gene in the treatment of cholestatic liver fibrosis （CLF）. MethodsThe technique of lentiviral transfection was used to induce the overexpression of the Numb gene in hUC-MSC （hUC-MSC^Numb-OE）， and hUC-MSC transfected with empty vector （hUC-MSC^OE-EV） was used as negative control. Bile duct ligation （BDL） was performed to establish a rat model of CLF， and then the rats were randomly divided into BDL group， hUC-MSC group， hUC-MSC^OE-EV group， and hUC-MSC^Numb-OE group， while a sham-operation group was also established. The rats in the intervention groups were given a single splenic injection of the corresponding cells after BDL， and samples were collected at the end of week 4. Related indicators were measured， including serum biochemistry， liver histopathology， the content of hydroxyproline （Hyp） in the liver， hepatic stellate cell activation， ductular reaction， liver regeneration， and the expression levels of key molecules in the Numb-p53 signaling axis. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the BDL group， the hUC-MSC group and the hUC-MSC^OE-EV group had significant reductions in the levels of serum biochemical parameters （aspartate aminotransferase， gamma-glutamyl transpeptidase， total bile acid， total bilirubin， and direct bilirubin）， liver fibrosis markers （the content of Hyp and the expression levels of alpha-smooth muscle actin， tumor necrosis factor-α， and transforming growth factor-beta 1）， and ductular reaction markers （the expression levels of CK7 and CK19） （all P <0.05）， and compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significantly greater improvements in the above indicators （all P <0.05）. In addition， compared with the hUC-MSC^OE-EV group， the hUC-MSC^Numb-OE group had significant improvements in the expression levels of liver regeneration-related markers （albumin and hepatocyte nuclear factor 4α） and the molecules associated with the Numb-p53 signaling axis （Numb， pNumb， Mdm2， and p53） （all P <0.05）. ConclusionOverexpression of the Numb gene can enhance the therapeutic effect of hUC-MSC on CLF， possibly by activating the Numb-PTB^L-p53-HNF4α axis， promoting the hepatic differentiation of hUC-MSCs and subsequently enhancing liver regeneration.

BACKGROUND:Steroid-induced femoral head necrosis is mostly caused by long-term and extensive use of hormones,but its specific pathogenesis is not yet clear and needs further study. OBJECTIVE:To screen out the differential miRNAs in osteoclast exosomes after the intervention of Panax notoginseng saponins,and on this basis,to further construct an osteogenic-related ferroptosis regulatory network to explore the potential mechanism and research direction of steroid-induced osteonecrosis of the femoral head. METHODS:MTT assay was used to detect the toxic effects of different concentrations of dexamethasone and different mass concentrations of Panax notoginseng saponins on Raw264.7 cell line.Tartrate resistant acid phosphatase staining and TUNEL assay were used to detect the effects of Panax notoginseng saponins on osteoclast inhibition and apoptosis.Exosomes were extracted from cultured osteoclasts with Panax notoginseng saponins intervention.Exosomes from different groups were sequenced to identify differentially expressed miRNAs.CytoScape 3.9.1 was used to construct and visualize the regulatory network between differentially expressed miRNAs and mRNAs.Candidate mRNAs were screened by GO analysis and KEGG analysis.Finally,the differential genes related to ferroptosis were screened out,and the regulatory network of ferroptosis-related genes was constructed. RESULTS AND CONCLUSION:(1)The concentration of dexamethasone(0.1 μmol/L)and Panax notoginseng saponins(1 736.85 μg/mL)suitable for intervention of Raw264.7 cells was determined by MTT assay.(2)Panax notoginseng saponins had an inhibitory effect on osteoclasts and could promote their apoptosis.(3)Totally 20 differentially expressed miRNAs were identified from osteoclast-derived exosome samples,and 11 differentially expressed miRNAs related to osteogenesis were predicted by target mRNAs.The regulatory networks of 4 up-regulated differentially expressed miRNAs corresponding to 155 down-regulated candidate mRNAs and 7 down-regulated differentially expressed miRNAs corresponding to 238 up-regulated candidate mRNAs were constructed.(4)Twenty-four genes related to ferroptosis were screened out from the differential genes.Finally,12 networks were constructed(miR-98-5p/PTGS2,miR-23b-3p/PTGS2,miR-425-5p/TFRC,miR-133a-3p/TFRC,miR-185-5p/TFRC,miR-23b-3p/NFE2L2,miR-23b-3p/LAMP2,miR-98-5p/LAMP2,miR-182-5p/LAMP2,miR-182-5p/TLR4,miR-23b-3p/ZFP36,and miR-182-5p/ZFP36).These results indicate that Panax notoginseng saponins may regulate osteoblast ferroptosis by regulating the expression of miRNAs derived from osteoclast exosomes,thus providing a new idea for the study of the mechanism of steroid-induced femoral head necrosis.

Aim To investigate the antagonistic effect of Schizandrin A(SchA)on oxidative stress-induced endothelial dysfunction and its mechanism of action.Methods Human umbilical vein endothelial cells(HUVECs)were selected as the research subjects,and the effects of SchA on cell viability were detected by MTT assay;the content of ROS in the cells was detec-ted by flow cytometry;the content of MDA and CAT in the cells,and the content of NO and ET-1 in the cell supernatant were detected by kit assay;and the expres-sion of SOD1,p-eNOS/eNOS proteins,and ET-1 in the cell supernatant were detected by Western blot.Immu-nofluorescence experiments were performed to detect Nrf2 entry into the nucleus of cells.Results SchA re-versed the LPS-or hypoxia-induced increase in ROS and MDA content as well as the decrease in SOD1 and CAT content in HUVECs by activating the Nrf2/Keap1/HO-1 signaling pathway.SchA inhibited the decrease of p-eNOS and eNOS protein expression in HUVECs cells,as well as NO content in cell culture medium and the increase of ET-1 content induced by LPS.The Nrf2 inhibitor ML385 reversed the antagonis-tic effects of SchA on oxidative stress and endothelial dysfunction.Conclusions SchA antagonized LPS and hypoxia-induced oxidative stress,and SchA amelio-rated oxidative stress-induced endothelial dysfunction by up-regulating the Nrf2/Keap1/HO-1 signaling path-way.

Objective To observe the value of enhanced MRI"strawberry sign"for differentiating solitary predominantly cystic brain metastasis and glioma.Methods Thirty-four patients with solitary predominantly cystic(cystic proportion greater than 50％)brain metastasis(metastasis group)and 43 with solitary predominantly cystic glioma(glioma group)were retrospectively enrolled,and the value of"strawberry sign"showed on contrast enhanced T1WI(CE-T1WI)for differentiation was analyzed.Results The detection rate of"strawberry sign"in metastasis group was 44.12％(15/34),and the primary cancer was lung adenocarcinoma in 6 cases(6/15,40.00％),small cell lung cancer in 3 cases(3/15,20.00％),as well as lung squamous cell carcinoma,breast cancer,colon adenocarcinoma,endometrioid carcinoma,fallopian tube adenocarcinoma and rectal melanoma each in 1 case(1/15,6.67％).Meanwhile,the detection rate of"strawberry sign"in glioma group was 18.60％(8/43),and all were observed in WHO grade 4 gliomas.The detection rate of"strawberry sign"in metastasis group was higher than that in glioma group,which was not related to patients' gender(P=0.442).The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of"strawberry sign"for differentiating solitary predominantly cystic brain metastasis and glioma was 44.12％,81.40％,64.94％,65.22％and 64.81％,respectively.Conclusion"Strawberry sign"showed on CE-T1WI was helpful for differentiating solitary predominantly cystic brain metastasis and glioma.

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 explore the effect of repetitive transcranial magnetic stimulation(rTMS)on the sleep disorder and examination results of recruits.Methods At a training base,the Pittsburgh Sleep Quality Index(PSQI)was used to screen the recruits with sleep disorders(total score of PSQI>7).The recruits were randomly assigned to rTMS group or sham rTMS group.Both groups received cognitive and behavioral intervention therapy,including sleep health education and relaxation training.Moreover,the rTMS group was treated with rTMS at the right posterior parietal lobe by continuous theta burst stimulation(cTBS)twice a day at an interval of at least 50 min for 5 consecutive days as a course of treatment with an interval of 2 days for a total of 2 courses of treatment.The coil position and stimulus intensity of sham rTMS group were consistent with the rTMS group,but the head of subjects was perpendicular to the coil plane and there was no effective stimulation.Before and after treatment,PSQI,self-rating depression scale,generalized anxiety disorder-7 and health questionnaire-15 were used to evaluate the sleep,mood and physical state of the recruits.The training result was assessed one month after treatment.The total effective rate of PSQI improvement and examination results were compared between the two groups.The independent influencing factors of excellent examination result were analyzed.Results Among 351 recruits,83 with sleep disorders completed treatment and follow-up.There were 40 patients in the rTMS group and 43 patients in the sham rTMS group.There was no significant difference between the two groups at baseline.After treatment,the total effective rate of PSQI improvement in the rTMS group was higher than that in the sham rTMS group(77.50%vs 53.49%,P=0.022).The average examination score and excellent rate of the rTMS group were higher than those of the sham rTMS group(91.58±3.19 vs 89.47±4.67,P=0.020;85%vs 65.12%,P=0.037).Logistic regression analysis showed that the treatment mode(rTMS group)was the independent influencing factor of excellent examination results(P=0.032).Conclusion rTMS can effectively and safely improve the sleep disorders and examination results of recruits.rTMS may play a positive role in improving the learning and training effect of recruits,which needs to be further proved.

Objective:This study aims to determine the risk perception, evacuation decision-making, and influencing factors related to typhoon disasters among public.Methods:A cross-sectional study will be conducted in residents of Hainan from September 2024 to January 2025. The study will employ chi-square tests, t-tests, and binary logistic regression analysis to examine factors influencing evacuation behavior decisions. Furthermore, structural equation modeling based on ordered choice model will be constructed to validate the mechanisms through which risk perception affects evacuation decision-making processes.Results:Among 517 respondents from 11 administrative districts (counties) in Hainan Province, 62.09% of the residents were willing to evacuate. The decision of public evacuation behavior was significantly related to disaster knowledge, official trust, risk perception, source of warning information and some demographic characteristics. Structural equation modeling demonstrated that warning information sources positively correlated with disaster knowledge and official trust (path coefficients: 0.363, 0.315, both P < 0.001). Both disaster knowledge and official trust showed positive correlations with risk perception (path coefficients: 0.157, 0.165, both P < 0.001), while risk perception positively influenced evacuation decisions (path coefficient: 0.137, P = 0.003). Moreover, source of warning information, disaster knowledge and official trust further positively affect evacuation behavior decision through risk perception, a key mediating variable. Conclusions:Disaster knowledge, official trust, risk perception and other factors can directly or indirectly affect the evacuation behavior of the public following the typhoon disaster. In typhoon-prone areas, it is recommended to enhance public risk perception through strategies such as authoritative training, diversified early warning channels, and improving government credibility, thereby promoting disaster preparedness and evacuation behaviors.