Aim To study the mechanism of adipose mesenchymal stem cell exosomes(ASC-exo)inhibition of fluorescein isothiocyanate(FITC)-induced atopic dermatitis(AD).Methods The mouse age,extrac-tion method,and the concentration of a solution of typeⅠ collagen enzyme and other conditions were compared to study the effects on the morphology and quantity of adipose mesenchymal stem cells(ASCs)after extrac-ted.FITC-induced mouse model in vivo was estab-lished and different doses of ASC-exo were given to measure ear thickness,ear weight and ear scratching times of mice.HE staining was used to observe the pathological changes of ear tissue of mice.The non-toxicity of ASC-exo was detected.IgE,IL-5,IL-13 and other cytokines were detected by ELISA.The gene ex-pressions of TSLP,IL-33,occludin,Claudin-1(CLDN-1)and E-cadherin were detected by RT-qPCR.The protein expression was detected by immunohistochemis-try.Results An efficient method for extracting ASCs was established.Compared with the blank group,mice in the model group showed obvious AD symptoms.Compared with the model group,ASC-exo administra-tion group significantly reduced the number of ear scratches,epidermal thickening,inflammatory cell infil-tration and the secretion of Th2 cytokines IL-5 and IL-13.Meanwhile,ASC-exo administration group signifi-cantly increased the expression of structural proteins CLDN-1 and occludin in epithelial cells and decreased the expression of TSLP and IL-33.Conclusions ASC-exo can significantly improve Th2 skin inflamma-tion in AD mice,and its mechanism may be through in-creasing the expression of tight junction proteins and adhesion link protein in epithelial cells,repairing the skin barrier,and inhibiting the key promoters of allergy TSLP and IL-33.

Objective This study aimed to investigate the antimicrobial resistance profiles of bacterial strains isolated from pediatric intensive care units(PICU)in China for better antimicrobial therapy.Methods Clinical isolates were collected from 17 institutions,including tertiary care children's hospitals and pediatric department of tertiary general hospitals in China from January 1,2020 to December 31,2022.Antimicrobial susceptibility testing was carried out according to a unified protocol using Kirby-Bauer method or automated systems.Results were interpreted according to the breakpoints released by the Clinical and Laboratory Standards Institute(CLSI)in 2020.Results A total of 10 688 isolates were collected,including gram-positive organisms(39.2％)and gram-negative organisms(60.8％).The top three organisms were S.aureus(13.6％,1 453/10 688),A.baumannii(10.0％,1 067/10 688),and coagulase-negative Staphylococcus(9.9％,1 058/10 688).Multi-drug resistant organisms(MDROs)were very common in children.The prevalence of methicillin-resistant Staphylococcus aureus(MRSA),carbapenem-resistant Enterobacterales(CRE),carbapenem-resistant E.coli,carbapenem-resistant K.pneumoniae(CRKP),carbapenem-resistant A.baumannii(CRAB),and carbapenem-resistant P.aeruginosa(CRPA)was 41.1％,19.4％,8.8％,30.9％,67.4％,and 28.8％,respectively.Overall,more than 50％of Enterobacteriales isolates were resistant to cephalosporins,while nearly 25％of Enterobacteriales isolates were resistant to carbapenems.MDROs were highly resistant to commonly used antibiotics.More than 80％of CRE and CRAB strains were resistant to all beta-lactam antibiotics.CRE and CRAB showed low resistance rates to tigecycline and polymyxin.CRPA showed lower resistance rates to piperacillin,beta-lactamase inhibitor combinations than the resistance rates to third and fourth generation cephalosporins.All of the Staphylococcus and Enterococcus isolates were susceptible to vancomycin and tigecycline.None of PRSP strains isolated from meningitis and nonmeningitis samples were resistant to rifampicin,vancomycin,or linezolid.The prevalence of β-lactamase-negative ampicillin-resistant(BLNAR)strains was 43.3％in Haemophilus influenzae.Conclusions MDROs were prevalent in PICU.It is necessary to establish an effective multidisciplinary team(MDT)to control the antimicrobial resistance.

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.

Objective:To explore the relationship between suicide attempts,school bullying,and psychological resilience in children and adolescents with major depressive disorder(MDD)and school bullying and psychological resilience.Methods:A total of 784 patients with MDD aged 10 to 18 years were included.The Chinese version of the Olweus Bullying Victimization Questionnaire,Adolescent Psychological Resilience Scale,and a suicide attempt assessment were utilized to evaluate school bullying,psychological resilience,and suicide attempt.Stepwise logistic regression was applied to identify the associated factors of suicide attempts.Results:The occurrence of suicide at-tempts in children and adolescents with MDD was positively associated with physical bullying(OR=1.85,95％CI:1.14-3.02)and indirect bullying(OR=1.48,95％CI:1.06-2.04),and negatively associated with higher levels of goal focus(OR=0.62,95％CI:0.45-0.85)and positive cognition(OR=0.62,95％CI:0.45-0.85)at higher levels.Conclusion:Bullying significantly increases the risk of suicide attempts in children and adolescents with MDD,while higher psychological resilience could mitigate this risk.

OBJECTIVE To explore the functional substance basis of Jinhong Tablet in the treatment of chronic superficial gastri-tis(CSG).METHODS Three different models were constructed to investigate the anti-inflammatory and antioxidant effects,func-tional material basis of Jinhong Tablet:inflammatory model in human gastric epithelial cells(GES-1)induced by lipopolysaccharide(LPS),LPS-induced inflammatory model in mouse gastric organoids,and ethanol-induced oxidative damage model in GES-1 cells.MTS assay was performed to detect cell proliferation activity;qPCR was applied to measure the relative mRNA expression of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),interleukin-6(IL-6),and interleukin-8(IL-8)in cells and gastric organoids;and the levels of superoxide dismutase(SOD),malondialdehyde(MDA),and reactive oxygen species(ROS)in cells were detected.RESULTS Jinhong Tablet and 10 functional components significantly reduced the relative expression of inflammation-relat-ed genes TNF-α,IL-1β,IL-6,and IL-8 in LPS-induced GES-1 cells and gastric organoids,suggesting that these 10 components are the functional substance basis for the anti-inflammatory effects of Jin Hong Tablet.Jin Hong Tablet and 11 functional components markedly decreased the levels of MDA and ROS and increased the activity of SOD,indicating that these 11 components were the func-tional substance basis of the antioxidant effects of Jinhong Tablet.CONCLUSION Through in vitro cell and gastric organoid experi-ments,it has been preliminarily determined that allocryptopine,corydaline,dehydrocorydaline,palmatine hydrochloride,chlorogenic acid,costunolide,rutin,quercitrin,dehydrocostus lactone,tetrahydrocoptisine,isochlorogenic acid B,toosendanin,protopine,and quercetin are the functional material basis of Jinhong Tablet in treating CSG,accumulating scientific evidence for the enhancement of the quality standards of Jinhong Tablet.

This study was aimed at developing an in vitro fluorescent substrate assay for the activity of leucyl aminopeptid-ase(LAP)from Echinococcus multilocularis and comparing it with the chemical chromogenic substrate enzyme activity assay.Through the establishment of reaction conditions for the fluorescent substrate-based in vitro enzyme activity assay,we com-pared the differences between the fluorescent substrate L-Leucine-7-amido-4-methylocoumarin(Leu-AMC)and the chemical chromogenic substrate L-Leucine-4-nitroanilide(Leu-pNA)through molecular docking,inhibition rates,and precision measures.Molecular docking revealed that the fluorescent substrate Leu-AMC had higher affinity for the protein than the chemical chromogenic substrate Leu-pNA.Through analysis of the effects of varying reaction conditions on fluorescence intensi-ty,we optimized the fluorescent substrate enzyme activity assay to demonstrate favorable performance at a reaction temperature of 37℃,a pH of 9.0,a protein concentration of 800 nmol/L,and a reaction duration of 60 minutes.Leu-AMC exhibited significant and distinct responses at a 5 μmol/L substrate concentration,under varying substrate conditions.The fluo-rescent substrate assay demonstrated more significant intergroup differences than the chemical chromogenic substrate assay when various inhibitors were added.This study established a fluorescence-based enzyme activity assay for leucyl aminopeptidase from Echinococcus multilocularis by using Leu-AMC as the substrate;this method demonstrated a more significant intergroup difference and sensitivity than the chemical chromogenic substrate assay.

Tumor microenvironment(TME)is the foundation for tumor survival,which is composed of various types of cells,tumor blood vessels,secretory factors,and extracellular matrix(ECM)within the tumor.The unique regulatory mechanism triggered by the vigorous metabolic demand of tumor plays an important role in its tumorigenesis,metastasis,invasion,and treatment resistance.A deeper understanding of the metabolic transformation and tumor-immune cell interactions in the TME will enable the development of therapeutic technologies that precisely target TME metabolism,facilitate the development of combination treatment strategies,and improve the clinical response rate of existing immunotherapies.This paper reviews the composition,metabolism and regulatory mechanisms of TME,summarizes the research progress of immunotherapy strategies targeting the physiological characteristics of TME,and discusses the prospects for clinical application of precision immunotherapy strategies targeting TME,which are expected to enhance immunotherapy drugs response and infiltration degree.

High altitude heart disease(HAHD)is a chronic mountain sickness in which the body is exposed to high altitude(＞2 500 m)hypobaric hypoxia environment for a long time.HAHD has high morbidity and poor prognosis,and pulmonary hypertension is the main causative mechanism for its develop-ment.The phosphodiesterase-5 inhibitor sildenafil has become a hot drug for the treatment of pulmonary hypertension.This paper reviews the progress of HAHD and discusses the mechanism of action and effectiveness of sildenafil in the treatment of HAHD,with a view to providing a basis for the treatment of HAHD with sildenafil.

OBJECTIVE To explore the functional substance basis of Jinhong Tablet in the treatment of chronic superficial gastri-tis(CSG).METHODS Three different models were constructed to investigate the anti-inflammatory and antioxidant effects,func-tional material basis of Jinhong Tablet:inflammatory model in human gastric epithelial cells(GES-1)induced by lipopolysaccharide(LPS),LPS-induced inflammatory model in mouse gastric organoids,and ethanol-induced oxidative damage model in GES-1 cells.MTS assay was performed to detect cell proliferation activity;qPCR was applied to measure the relative mRNA expression of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),interleukin-6(IL-6),and interleukin-8(IL-8)in cells and gastric organoids;and the levels of superoxide dismutase(SOD),malondialdehyde(MDA),and reactive oxygen species(ROS)in cells were detected.RESULTS Jinhong Tablet and 10 functional components significantly reduced the relative expression of inflammation-relat-ed genes TNF-α,IL-1β,IL-6,and IL-8 in LPS-induced GES-1 cells and gastric organoids,suggesting that these 10 components are the functional substance basis for the anti-inflammatory effects of Jin Hong Tablet.Jin Hong Tablet and 11 functional components markedly decreased the levels of MDA and ROS and increased the activity of SOD,indicating that these 11 components were the func-tional substance basis of the antioxidant effects of Jinhong Tablet.CONCLUSION Through in vitro cell and gastric organoid experi-ments,it has been preliminarily determined that allocryptopine,corydaline,dehydrocorydaline,palmatine hydrochloride,chlorogenic acid,costunolide,rutin,quercitrin,dehydrocostus lactone,tetrahydrocoptisine,isochlorogenic acid B,toosendanin,protopine,and quercetin are the functional material basis of Jinhong Tablet in treating CSG,accumulating scientific evidence for the enhancement of the quality standards of Jinhong Tablet.