ObjectiveTo investigate the molecular mechanisms by which salvianolic acid B （SalB） inhibits epithelial-mesenchymal transition （EMT） in non-small cell lung cancer （NSCLC） by downregulating phosphoribosylaminoimidazole carboxylase and phosphoribosylaminoimidazole succinocarboxamide synthetase （PAICS） expression. MethodsNSCLC A549 cells and normal bronchial epithelial cells （bronchial epithelium transformed with Ad12-SV40 2B， BEAS-2B） were used as models. Cell viability was assessed using the cell counting kit-8 （CCK-8） assay after treatment with SalB （0， 50， 100， 200， 300， 400， 500 μmol·L^-1 for 24 or 48 h to determine effective and safe intervention concentrations. Cell proliferation， cell cycle distribution， and apoptosis were evaluated by 5-ethynyl-2′-deoxyuridine （EdU） staining and flow cytometry， respectively. Wound healing and Transwell invasion assays were performed to assess cell migration and invasion. RNA sequencing combined with bioinformatic analysis was conducted to identify differentially expressed genes and functional enrichment. Molecular docking was used to predict the binding ability between SalB and PAICS， and the cellular thermal shift assay （CETSA） was performed to evaluate the effect of SalB on the thermal stability of the PAICS protein. Western blot （WB） was used to detect the effects of SalB on PAICS and EMT-related proteins （E-cadherin， N-cadherin， Vimentin， Snail， and Slug）. A functional rescue assay was conducted by PAICS overexpression via plasmid transfection. ResultsCompared with the control group， SalB inhibited A549 cell viability in a dose-dependent manner （P<0.05）， and the effective concentrations （≤300 μmol·L^-1） showed no significant cytotoxicity in BEAS-2B cells. Within this concentration range， SalB significantly inhibited A549 cell proliferation， migration， and invasion， and induced G₀/G₁ phase arrest and apoptosis （P<0.05）. Transcriptomic analysis showed that SalB significantly downregulated PAICS expression， and its functions were enriched in cell proliferation and EMT. Bioinformatic analysis indicated that PAICS is highly expressed in lung adenocarcinoma and is associated with poor prognosis （P<0.01）. Molecular docking showed that SalB has strong binding ability to PAICS （binding energy -9.1 kcal·mol^-1. CETSA results showed that SalB significantly increased the thermal stability of the PAICS protein （P<0.05）. WB results showed that， compared with the control group， SalB dose-dependently downregulated PAICS expression， upregulated E-cadherin， and downregulated N-cadherin， Vimentin， Snail， and Slug （P<0.05）. Functional rescue experiments showed that， compared with the empty vector group， PAICS overexpression significantly enhanced A549 cell proliferation， migration， and invasion， promoted cell cycle progression， and inhibited apoptosis （P<0.05）. Meanwhile， compared with the empty vector + SalB-H group， PAICS overexpression partially reversed the inhibitory effects of SalB on malignant phenotypes and EMT-related proteins （N-cadherin， Vimentin， Snail， and Slug）， and downregulated E-cadherin expression （P<0.05，P<0.01）， indicating that PAICS is a key functional target mediating the antitumor effects of SalB. ConclusionSalB effectively inhibits EMT progression and cell cycle progression in A549 cells by downregulating PAICS expression， thereby exerting anti-NSCLC effects. This study not only reveals that PAICS is a key functional target through which SalB regulates EMT， but also provides experimental evidence supporting SalB as a potential candidate drug for inhibiting NSCLC metastasis.

ObjectiveTo investigate the mechanisms by which eupatilin （Eup） inhibits proliferation， invasion， and metastasis of non-small cell lung cancer （NSCLC） through the enhancer of zeste homolog 2/histone H3 lysine 27 trimethylation （EZH2/H3K27me3） signaling pathway. MethodsIn vivo， a subcutaneous xenograft tumor model was established in nude mice using H1299 cells to evaluate the anti-NSCLC effects of Eup. Immunohistochemistry （IHC-P） was used to detect the expression of proliferation- and invasion/metastasis-related proteins， including proliferating cell nuclear antigen （PCNA）， matrix metalloproteinase-2 （MMP-2）， matrix metalloproteinase-9 （MMP-9）， and vascular endothelial growth factor A （VEGFA）. In vitro， cell counting kit-8 （CCK-8） assays were performed to determine the viability of H1299 cells treated with different concentrations of Eup （0-200 μmol·L^-1） and to select appropriate concentrations. Colony formation and 5-ethynyl-2′-deoxyuridine （EdU） assays were used to evaluate cell proliferation. Wound healing and invasion assays were conducted to assess cell migration and invasion. Human umbilical vein endothelial cell （HUVEC） angiogenesis assays were used to evaluate the effects of Eup on angiogenesis. Transcriptomic analysis was performed to identify the targets of Eup in H1299 cells and to explore its major functions. Molecular docking and molecular dynamics simulations were conducted to predict the binding affinity and interaction stability between Eup and its target proteins. Western blot was used to detect the effects of Eup on the expression levels of EZH2/H3K27me3 pathway-related proteins and proliferation- and invasion/metastasis-related proteins， including PCNA， MMP-2， MMP-9， and VEGFA. ResultsIn the subcutaneous xenograft model， compared with the model group， Eup treatment dose-dependently inhibited the growth of H1299 xenograft tumors， and the tumor inhibition rate was significantly increased （P<0.05）. IHC-P results showed that， compared with the model group， high-dose Eup significantly reduced the expression levels of PCNA， MMP-2， MMP-9， and VEGFA in vivo （P<0.05）. In vitro， compared with the control group， Eup inhibited the proliferation， invasion， and metastasis of NSCLC cells in a concentration-dependent manner. Transcriptomic analysis further showed that， compared with the control group， Eup significantly downregulated EZH2 expression， and its functional effects were associated with inhibition of tumor metastasis. Molecular docking and molecular dynamics simulations indicated that Eup exhibited strong binding affinity with EZH2 and stable interactions. Western blot results demonstrated that， compared with the model group， Eup significantly inhibited， in a dose-dependent manner， the expression levels of EZH2， H3K27me3， and proliferation- and invasion/metastasis-related proteins （PCNA， MMP-2， MMP-9， and VEGFA） in both in vivo and in vitro experiments （P<0.05）. In vitro， compared with the control group， overexpression of EZH2 via plasmid transfection partially reversed the inhibitory effects of Eup on the expression of key proteins involved in proliferation and invasion/metastasis in H1299 cells. ConclusionEup effectively inhibits the proliferation， migration， and invasion of H1299 cells both in vivo and in vitro. The underlying mechanism may be related to inhibition of the EZH2/H3K27me3 signaling pathway and downregulation of proliferation- and invasion/metastasis-related proteins， including PCNA， MMP-2， MMP-9， and VEGFA. Eup may serve as a potential therapeutic agent for suppressing proliferation and invasion/metastasis in NSCLC.

ObjectiveTo investigate the molecular mechanisms by which salvianolic acid B （SalB） inhibits epithelial-mesenchymal transition （EMT） in non-small cell lung cancer （NSCLC） by downregulating phosphoribosylaminoimidazole carboxylase and phosphoribosylaminoimidazole succinocarboxamide synthetase （PAICS） expression. MethodsNSCLC A549 cells and normal bronchial epithelial cells （bronchial epithelium transformed with Ad12-SV40 2B， BEAS-2B） were used as models. Cell viability was assessed using the cell counting kit-8 （CCK-8） assay after treatment with SalB （0， 50， 100， 200， 300， 400， 500 μmol·L^-1 for 24 or 48 h to determine effective and safe intervention concentrations. Cell proliferation， cell cycle distribution， and apoptosis were evaluated by 5-ethynyl-2′-deoxyuridine （EdU） staining and flow cytometry， respectively. Wound healing and Transwell invasion assays were performed to assess cell migration and invasion. RNA sequencing combined with bioinformatic analysis was conducted to identify differentially expressed genes and functional enrichment. Molecular docking was used to predict the binding ability between SalB and PAICS， and the cellular thermal shift assay （CETSA） was performed to evaluate the effect of SalB on the thermal stability of the PAICS protein. Western blot （WB） was used to detect the effects of SalB on PAICS and EMT-related proteins （E-cadherin， N-cadherin， Vimentin， Snail， and Slug）. A functional rescue assay was conducted by PAICS overexpression via plasmid transfection. ResultsCompared with the control group， SalB inhibited A549 cell viability in a dose-dependent manner （P<0.05）， and the effective concentrations （≤300 μmol·L^-1） showed no significant cytotoxicity in BEAS-2B cells. Within this concentration range， SalB significantly inhibited A549 cell proliferation， migration， and invasion， and induced G₀/G₁ phase arrest and apoptosis （P<0.05）. Transcriptomic analysis showed that SalB significantly downregulated PAICS expression， and its functions were enriched in cell proliferation and EMT. Bioinformatic analysis indicated that PAICS is highly expressed in lung adenocarcinoma and is associated with poor prognosis （P<0.01）. Molecular docking showed that SalB has strong binding ability to PAICS （binding energy -9.1 kcal·mol^-1. CETSA results showed that SalB significantly increased the thermal stability of the PAICS protein （P<0.05）. WB results showed that， compared with the control group， SalB dose-dependently downregulated PAICS expression， upregulated E-cadherin， and downregulated N-cadherin， Vimentin， Snail， and Slug （P<0.05）. Functional rescue experiments showed that， compared with the empty vector group， PAICS overexpression significantly enhanced A549 cell proliferation， migration， and invasion， promoted cell cycle progression， and inhibited apoptosis （P<0.05）. Meanwhile， compared with the empty vector + SalB-H group， PAICS overexpression partially reversed the inhibitory effects of SalB on malignant phenotypes and EMT-related proteins （N-cadherin， Vimentin， Snail， and Slug）， and downregulated E-cadherin expression （P<0.05，P<0.01）， indicating that PAICS is a key functional target mediating the antitumor effects of SalB. ConclusionSalB effectively inhibits EMT progression and cell cycle progression in A549 cells by downregulating PAICS expression， thereby exerting anti-NSCLC effects. This study not only reveals that PAICS is a key functional target through which SalB regulates EMT， but also provides experimental evidence supporting SalB as a potential candidate drug for inhibiting NSCLC metastasis.

ObjectiveTo investigate the mechanisms by which eupatilin （Eup） inhibits proliferation， invasion， and metastasis of non-small cell lung cancer （NSCLC） through the enhancer of zeste homolog 2/histone H3 lysine 27 trimethylation （EZH2/H3K27me3） signaling pathway. MethodsIn vivo， a subcutaneous xenograft tumor model was established in nude mice using H1299 cells to evaluate the anti-NSCLC effects of Eup. Immunohistochemistry （IHC-P） was used to detect the expression of proliferation- and invasion/metastasis-related proteins， including proliferating cell nuclear antigen （PCNA）， matrix metalloproteinase-2 （MMP-2）， matrix metalloproteinase-9 （MMP-9）， and vascular endothelial growth factor A （VEGFA）. In vitro， cell counting kit-8 （CCK-8） assays were performed to determine the viability of H1299 cells treated with different concentrations of Eup （0-200 μmol·L^-1） and to select appropriate concentrations. Colony formation and 5-ethynyl-2′-deoxyuridine （EdU） assays were used to evaluate cell proliferation. Wound healing and invasion assays were conducted to assess cell migration and invasion. Human umbilical vein endothelial cell （HUVEC） angiogenesis assays were used to evaluate the effects of Eup on angiogenesis. Transcriptomic analysis was performed to identify the targets of Eup in H1299 cells and to explore its major functions. Molecular docking and molecular dynamics simulations were conducted to predict the binding affinity and interaction stability between Eup and its target proteins. Western blot was used to detect the effects of Eup on the expression levels of EZH2/H3K27me3 pathway-related proteins and proliferation- and invasion/metastasis-related proteins， including PCNA， MMP-2， MMP-9， and VEGFA. ResultsIn the subcutaneous xenograft model， compared with the model group， Eup treatment dose-dependently inhibited the growth of H1299 xenograft tumors， and the tumor inhibition rate was significantly increased （P<0.05）. IHC-P results showed that， compared with the model group， high-dose Eup significantly reduced the expression levels of PCNA， MMP-2， MMP-9， and VEGFA in vivo （P<0.05）. In vitro， compared with the control group， Eup inhibited the proliferation， invasion， and metastasis of NSCLC cells in a concentration-dependent manner. Transcriptomic analysis further showed that， compared with the control group， Eup significantly downregulated EZH2 expression， and its functional effects were associated with inhibition of tumor metastasis. Molecular docking and molecular dynamics simulations indicated that Eup exhibited strong binding affinity with EZH2 and stable interactions. Western blot results demonstrated that， compared with the model group， Eup significantly inhibited， in a dose-dependent manner， the expression levels of EZH2， H3K27me3， and proliferation- and invasion/metastasis-related proteins （PCNA， MMP-2， MMP-9， and VEGFA） in both in vivo and in vitro experiments （P<0.05）. In vitro， compared with the control group， overexpression of EZH2 via plasmid transfection partially reversed the inhibitory effects of Eup on the expression of key proteins involved in proliferation and invasion/metastasis in H1299 cells. ConclusionEup effectively inhibits the proliferation， migration， and invasion of H1299 cells both in vivo and in vitro. The underlying mechanism may be related to inhibition of the EZH2/H3K27me3 signaling pathway and downregulation of proliferation- and invasion/metastasis-related proteins， including PCNA， MMP-2， MMP-9， and VEGFA. Eup may serve as a potential therapeutic agent for suppressing proliferation and invasion/metastasis in NSCLC.

Objective To observe the clinical efficacy of Si-hour"Supplementing Yang and Unblocking Collaterals"Electroacupuncture Therapy based on the midnight-midday ebb-flow theory in treating hemiplegia caused by ischemic stroke.Methods A total of 160 patients diagnosed with ischemic stroke hemiplegia who were treated in the wards and outpatient departments of Huaian Hospital of Traditional Chinese Medicine between January 2023 and June 2024 were selected as study subjects.Patients were randomly divided into an observation group and a control group using a random number table,with 80 cases in each group.Both groups received conventional internal medicine rehabilitation treatment.The control group received conventional acupuncture therapy,while the observation group received Si-hour"Supplementing Yang and Unblocking Collaterals"Electroacupuncture Therapy based on the midnight-midday ebb-flow theory.Treatment was administered for 2 weeks per course,with a total of 3 courses.After completion of treatment,clinical efficacy was evaluated by observing changes in traditional Chinese medicine(TCM)syndrome scores,simplified Fugl-Meyer Assessment(FMA)scores,modified Barthel Index(MBI)scores,fractional anisotropy(FA)values in the cerebral peduncle and posterior limb of internal capsule regions,modified Edinburgh-Scandinavian Stroke Scale(MESSS)scores,as well as plasma viscosity,hematocrit(HCT),and fibrinogen(FIB)levels before and after treatment in both groups.Results(1)The total effective rate was 86.25％(69/80)in the observation group and 70.00％(56/80)in the control group.The efficacy of the observation group was significantly superior to that of the control group,with a statistically significant difference(P＜0.05).(2)After treatment,TCM syndrome scores were significantly improved in both groups(P＜0.05),and the improvement in the observation group was significantly greater than that in the control group,with a statistically significant difference(P＜0.05).(3)After treatment,FMA and MBI scores were significantly improved in both groups(P＜0.05),and the improvement in the observation group was significantly greater than that in the control group,with a statistically significant difference(P＜0.05).(4)After treatment,FA values in the cerebral peduncle and posterior limb of internal capsule regions,as well as MESSS scores,were significantly improved in both groups(P＜0.05),and the improvement in the observation group was significantly greater than that in the control group,with a statistically significant difference(P＜0.05).(5)After treatment,plasma viscosity,HCT,and FIB levels were significantly improved in both groups(P＜0.05),and the improvement in the observation group was significantly greater than that in the control group,with a statistically significant difference(P＜0.05).Conclusion Si-hour"Supplementing Yang and Unblocking Collaterals"Electroacupuncture Therapy based on the midnight-midday ebb-flow theory significantly improves limb motor function,enhances neural conduction,and optimizes hemorheological parameters in patients with hemiplegia caused by ischemic stroke,demonstrating notable clinical efficacy.

Objective To summarize the whole process comprehensive management experience in transfemoral aortic valve replacement(TF-TAVR)using self-expanding valve in 79 patients with pure native aortic valve regurgitation(PNAR).Methods The nursing team adopted a multi-team collaboration approach.Preoperative nursing assessment and full preparation,enhanced psychological support,and sleep management were carefully carried out;during the operation,nurses well cooperated with doctor,implemented predictive care and intervention for possible complications;and after surgery the hemodynamics and respiratory functions were closely monitored to promptly detect and manage the complications,and to implement the infection prevention cluster management process and discharge preparation services.Besides,the comprehensive management measures throughout the entire process,the occurrence of complications and corresponding nursing responses,as well as the six-minute walk test before and after the operation were recorded.The Discharge Readiness Scale was used to evaluate the implementation of patient discharge readiness services so as to check the implementation effect of the comprehensive whole process management measures.Results Through the implementation of comprehensive whole process management measures,the surgery-related ventricular fibrillation and cardiac arrest obtained accurate and timely treatment,no newly-developed complications such as deep vein thrombosis of lower limbs occurred.Through the implementation of infection cluster nursing measures,the incidence of pulmonary infection in patients decreased from 52.00％in the early stage of carrying out the management measures to 9.26％.Through the implementation of discharge preparation services and continuous quality improvement,the left ventricular ejection fraction(LVEF)value in 64 patients receiving successful TAVR increased from(44.06±5.51)％to(54.67±5.20)％,and the difference was statistically significant(t=19.634,P＜0.001).On the day of discharge,the six-minute walk test distance increased from preoperative(131.39±39.36)meters to postoperative(180.77±29.72)meters,and the difference was statistically significant(t=10.898,P＜0.001).The average self-assessment score of discharge readiness of patients was(7.33±1.41)points.All patients were well recovered when discharged from hospital.Conclusion According to the different surgical key points and the difficult problems,full and effective implementation of comprehensive whole process management measures can ensure that the PNAR patients are able to smoothly pass through the perioperative period and obtain a satisfactory recovery after receiving TF-TAVR.

Objective To discuss the application effect of intravenous anesthesia with oxycodone plus propofol or oliceridine plus propofol for sedating elderly patients during endoscopic retrograde cholangiopancreatography(ERCP).Methods Sixty elderly patients,who were planned to receive ERCP in Shengli Oilfield Central Hospital from March to Sepcember 2024,were randomly divided into oxycodone group and oliceridine group,with 30 patients in each group.Intravenous anesthesia with oxycodone plus propofol or oliceridine plus propofol was adopted for the patients of the corresponding group.The patient's postoperative comfort score,the dosage of propofol used during surgery,the number of additional analgesics administered,the time of patient entering the operation room(T0),3 minutes after analgesia(T1),after anesthesia induction(T2),immediately upon examination(T3),time on arrival at the duodenal papilla(T4),and time on consciousness waking-up(T5)were recorded.The surgical time,consciousness waking-up time,endoscopist satisfaction degree,patient's satisfaction rate,and incidence of anesthesia-related adverse events were documented.Results The comparison of postoperative comfort scores showed that the score in the oliceridine group was(7.6±1.9)points,which was significantly higher than(6.6±1.3)points in the oxycodone group(t=2.23,P=0.03).The dosage of propofol used during surgery in the oliceridine group was significantly lower than that in the oxycodone group(P＜0.05).The mean arterial pressure(MAP),heart rate(HR),and respiratory rate(RR)at T1-T4 time points were significantly decreased in both groups when compared with their values at T0 time point(all P＜0.05).The reduction degrees of the above indexes at T1-T3 time points in the oxycodone group were more pronounced than those in the oliceridine group(all P＜0.05).At T4,MAP and HR were increased in both groups,which in the oxycodone group were remarkably higher than those in the oliceridine group(both P＜0.05).No statistically significantly difference in oxygen saturation(SpO2)existed between T1 time point and T0 time point(P＞0.05);but at the other time points,SpO2 was decreased to varying degrees in both groups,and the within-group comparison and between-group comparison showed that the differences in SpO2 were statistically significant(all P＜0.05).In oliceridine group,the time of patient's consciousness waking-up was obviously shorter than that in the oxycodone group(P＜0.05),and the endoscopist satisfaction degree and patient satisfaction rate were strikingly higher than those in the oxycodone group(both P＜0.05).The incidence of intraoperative adverse events in the oliceridine group was prominently lower than that in the oxycodone group(P＜0.05).No statistically significant difference in the incidence of adverse events during consciousness waking-up time existed between the two groups(P＞0.05),but the incidences of postoperative nausea,vomiting and respiratory depression in the oliceridine group was obviously lower than those in the oxycodone group(all P＜0.05).Conclusion In performing ERCP for elderly patients,oliceridine plus propofol is clinically safe and feasible with less adverse events,high satisfaction rate and higher patient's comfort level when compared with oxycodone plus propofol.

AIM:To investigate the impact of es-ketamine-mediated opioid-free anesthesia(OFA)on postoperative gastrointestinal function in patients undergoing laparoscopic distal gastrectomy for gas-tric cancer.METHODS:A total of 150 pa-tients,scheduled for elective laparoscopic distal gas-trectomy for gastric cancer and meeting the inclu-sion and exclusion criteria,were randomly assigned to either the OFA group or the opioid-based anes-thesia(OBA)group using a random number ta-ble,with 75 patients in each group.The OFA group was administered an anesthesia regimen pri-marily consisting of esketamine,while the OBA group received conventional opioid anesthesia,pri-marily consisting of sufentanil and remifentanil.The primary outcome measure was postoperative flatus time,defined as the interval from the end of sur-gery to the first passage of gas.RESULTS:The OFA group exhibited a shorter postoperative flatus time compared to the OBA group(P＜0.01).Intraopera-tive blood loss and norepinephrine consumption were significantly less in the OFA group compared to the OBA group(P＜0.05);the postoperative HADS-D score was better in the OFA group than in the OBA group,and both the OFA and OBA groups showed significantly lower postoperative HADS-A and HADS-D scores compared to their preoperative levels(P＜0.05);the incidence rate of abdominal distension was significantly lower in the OFA group compared to the OBA group(P＜0.05).CONCLUSION:The use of esketamine-mediated opioid-free anesthesia can expedite gastrointestinal function recovery,reduce hospital stay duration,and decrease postoperative adverse reactions in patients undergoing laparo-scopic distal gastrectomy for gastric cancer.

AIM:To investigate the impact of es-ketamine-mediated opioid-free anesthesia(OFA)on postoperative gastrointestinal function in patients undergoing laparoscopic distal gastrectomy for gas-tric cancer.METHODS:A total of 150 pa-tients,scheduled for elective laparoscopic distal gas-trectomy for gastric cancer and meeting the inclu-sion and exclusion criteria,were randomly assigned to either the OFA group or the opioid-based anes-thesia(OBA)group using a random number ta-ble,with 75 patients in each group.The OFA group was administered an anesthesia regimen pri-marily consisting of esketamine,while the OBA group received conventional opioid anesthesia,pri-marily consisting of sufentanil and remifentanil.The primary outcome measure was postoperative flatus time,defined as the interval from the end of sur-gery to the first passage of gas.RESULTS:The OFA group exhibited a shorter postoperative flatus time compared to the OBA group(P＜0.01).Intraopera-tive blood loss and norepinephrine consumption were significantly less in the OFA group compared to the OBA group(P＜0.05);the postoperative HADS-D score was better in the OFA group than in the OBA group,and both the OFA and OBA groups showed significantly lower postoperative HADS-A and HADS-D scores compared to their preoperative levels(P＜0.05);the incidence rate of abdominal distension was significantly lower in the OFA group compared to the OBA group(P＜0.05).CONCLUSION:The use of esketamine-mediated opioid-free anesthesia can expedite gastrointestinal function recovery,reduce hospital stay duration,and decrease postoperative adverse reactions in patients undergoing laparo-scopic distal gastrectomy for gastric cancer.

BackgroundStudents in secondary vocational health school are at the age of puberty and prone to depressive symptoms. Peer victimization and social media addiction are found to be crucial in influencing the development of depression， and positive mental health has been proven to alleviate depressive symptoms， whereas there remains a striking lack of research on the mediating role of positive mental health and social media addiction in the relationship between peer victimization and depressive symptoms among secondary vocational health school students. ObjectiveTo explore the relationship between peer victimization and depressive symptoms and investigate the mediating role of positive mental health and social media addiction， so as to provide references for the prevention of depression among secondary vocational health school students. MethodsFrom October to December 2020， a cluster sampling framework was utilized to recruit 7 307 students from a secondary vocational health school in Luzhou City， Sichuan Province. Assessments were performed using Multidimensional Peer Victimization Scale （MPVS）， Warwick-Edinburgh Mental Well-being Scale （WEMWBS）， Bergen Social Media Addiction Scale （BSMAS） and Patient Health Questionnaire Depression Scale-9 item （PHQ-9）. Spearman correlation analysis was calculated to determine correlations between scores of scales， Process 4.0 was employed to test the mediation effect， and the bias-corrected Bootstrap procedure was used to test the significance of the mediation effect. ResultsA total of 7 044 （96.40%） valid questionnaires were collected. And 4 391（62.34%）students were found to have depressive symptoms. Correlation analysis revealed that PHQ-9 score was positively correlated with BSMAS score and MPVS score （r=0.404， 0.506， P<0.01）. WEMWBS score was negatively correlated with PHQ-9 score， BSMAS score and MPVS score （r=-0.587， -0.259， -0.358， P<0.01）. BSMAS score was positively correlated with MPVS score （r=0.328， P<0.01）. Positive mental health played a mediating role in the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.130 （95% CI： 0.119~0.141）， accounting for 30.81% of the total effect. Social media addiction also mediated the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.052 （95% CI： 0.045~0.059）， accounting for 12.34% of the total effect. Positive mental health and social media addiction exhibited a chained mediation effect on the relationship between peer victimization and depressive symptoms， with an indirect effect value of 0.012 （95% CI： 0.010~0.014） and accounting for 2.84% of the total effect. ConclusionPeer victimization can affect the presence of depressive symptoms among secondary vocational health school students both directly and indirectly through either separate or chained mediation of positive mental health and social media addiction.