Objective To investigate the induction of senescence in L02 hepatocytes by low-dose fractionated X-ray radiation and its effects on oxidative stress, oxidative damage, and nuclear factor-κB (NF-κB) pathway protein levels. Methods L02 cells were subjected to fractionated X-ray irradiation at doses of 0.1, 0.2, and 0.5 Gy per fraction for a total of six fractions. Assays were performed 24 hours after the final irradiation. Measurements included SA-β-gal staining, the mRNAs of senescence-related genes p53 and p21 and their encoded proteins, mRNAs of genes encoding senescence-associated secretory phenotype factors (IL-6, IL-8, GM-CSF, MMP-15), reactive oxygen species, oxidative and anti-oxidative markers (malondialdehyde, glutathione, superoxide dismutase), DNA oxidative damage markers (8-OHdG and γ-H2AX), and NF-κB pathway protein levels. Results Compared with the control group, at 24 hours after the end of six irradiations, the number of cells positive in SA-β-gal staining was significantly increased in all dose groups. The mRNA and protein levels of p21 and p53 were significantly elevated in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The mRNA levels of genes encoding IL-6, GM-CSF, and MMP-15 were significantly increased in all dose groups (P < 0.05). The mRNA levels of the gene encoding IL-8 were significantly increased in the 0.2 Gy × 6 and 0.5 Gy × 6 groups (P < 0.05). The levels of reactive oxygen species, malondialdehyde, and glutathione were significantly increased in all dose groups (P < 0.01). The level of superoxide dismutase was significantly increased in the 0.5 Gy × 6 group (P < 0.01). The levels of 8-OHdG were significantly increased in all dose groups (P < 0.05). In both the 0.2 Gy × 6 and 0.5 Gy × 6 groups, the expression levels of γ-H2AX and p-NF-κB p65 were significantly increased (P < 0.05), and the levels of IκBα were significantly decreased (P < 0.05). Conclusion Low-dose fractionated X-ray radiation can induce senescence and cause alterations in oxidative stress, oxidative damage, and the levels of NF-κB pathway proteins in L02 hepatocytes.

ObjectiveTo improve the response capabilities to disasters and prevent major epidemics， it is of practical use to study the capability evaluation system of the national emergency medical rescue team that combines theoretical training and practical exercises， to enhance the overall quality of the teams. MethodsFirst， a capability assessment system for the national emergency medical rescue team was constructed based on the INSARAG External Classification （IEC） standards of the national emergency medical rescue team. Then， based on the outcome based education （OBE） concept， we conducted innovative research on the curriculum design and exercise programs for team building and member training. Finally， an empirical analysis was conducted on the effectiveness of the evaluation system and training exercises based on the statistical analysis of the comprehensive quality evaluation of the Shanghai national emergency medical rescue team from 2020 to 2023， as well as the empirical analysis of the rescue exercise on the Cruise of spectrum. ResultsBased on the linear regression analysis of each core competency indicators， the five core competencies in the evaluation system， including rescue skills， medical and health knowledge， disaster coping ability， team cooperation ability， and mental resilience training， were positively correlated with the cumulative number of trainings （r=0.71， r=0.76， r=0.81， r=0.84， r=0.96，all P<0.05）， indicating that the training was effective and the course design was reasonable. Empirical cases showed that the three-dimensional rescue drill model had remarkable results in the actual combat application and ability improvement of team members. ConclusionThe training courses and drills designed based on the three-level assessment system are effective in improving the comprehensive capabilities of the national emergency medical rescue team.

Objective:To compare the application effect of domestic and imported intravenous radiofrequency closure system in the treatment of primary varicose veins of lower extremities.Methods:This single-center prospective, non-inferiority randomized controlled trial was performed in the Department of Vascular Surgery, the Fourth Affiliated Hospital, Zhejiang University School of Medicine from January 2021 to January 2022. Patients with primary varicose veins of lower extremities who met the ataxation criteria were randomly assigned to the experimental group(domestic novel venous radiofrequency closure system) or the control group(imported venous radiofrequency closure system) in a ratio of 1∶1. The two groups of subjects were compared in terms of target vein closure rate, technical success rate, system operation performance, incidence of adverse events and incidence of serious adverse events(SAE) within 6 months after surgery. Quantitative data were compared by Mann-Whitney U test, and categorical data were compared by χ2 test and non-inferiority test. Results:A total of 80 subjects were included in the trial (41 in the experimental group and 39 in the control group), including 27 males and 53 females, aged ( M(IQR)) 55(23) years (range:40 to 78 years). There were 48 cases of left lower limb and 32 cases of right lower limb. The technical success rate and system control performance between the groups were 100%.The incidence of adverse events (58.5% (24/41) vs. 61.5% (24/39), χ2=0.075, P=0.784), and the incidence of SAE (7.3% (3/41) vs. 5.1% (2/39), χ2=0.163, P=0.686) within 6 months after surgery in experimental group and control group had no statistical significance. There was one device-related adverse event in each of the two groups. In the experimental group, one patient developed endovenous heat-induced thrombosis after surgery and recovered after taking rivaroxaban tablets. One patient in the control group had pain in the upper right thigh for more than 1 day after operation, which was cured after using analgesic cream. No device-related SAE occurred. The venous closure rate of the experimental group was 100% (38/38) at 6 months after surgery, and that of the control group was 97.4% (37/38). The difference between the two groups was 2.63% (95% CI:-3.19 to 8.45, Z=4.865, P<0.01), and the 95% CI lower limit of the difference in target venous closure rate between two groups was greater than the non-inferiority threshold of -10.00%. Conclusion:The early application effect of the new domestic intravenous radiofrequency closure system in patients with primary varicose veins of lower extremities is in line with expectations, it is not inferior to the imported system.

AIM:This study aims to examine the ependymin-related protein 1(EPDR1)expression in various tissues from wild-type C57BL/6 mice and type 2 diabetes(db/db)mice.The impact of EPDR1 on lipid accumulation in al-pha mouse liver 12(AML12)hepatocytes was also investigated.METHODS:Western blot was used to detect EPDR1 protein expression in the heart,liver,spleen,lung,kidney,gastrocnemius,brown adipose and brain tissues of C57BL/6 mice.Western blot and immunohistochemical(IHC)staining were also used to compare EPDR1 protein expression in the liver,gastrocnemius muscle,heart and kidney tissues of db/db and C57BL/6 mice.To develop an AML12 cell lipid deposi-tion model,palmitic acid(PA)+oleic acid(OA)was used,and the cells were transfected with adenovirus overexpressing EPDR1 or treated with exogenous recombinant EPDR1 protein(rEPDR1).ELISA was conducted to determine intracellu-lar triglyceride(TG)content,and oil red O staining was employed to assess the effect of EPDR1 on lipid accumulation in AML12 cells.RESULTS:Western blot and IHC staining results revealed that EPDR1 was widely expressed in various tis-sues of wild-type mice,with the liver exhibiting the highest protein expression level.However,EPDR1 expression was down-regulated in the liver,gastrocnemius muscle,heart and kidney tissues in diabetic db/db mice compared with wild-type mice.Oil red O staining revealed that overexpression of EPDR1 in AML12 liver cells or rEPDR1 treatment led to re-duced lipid accumulation.Furthermore,the TG content significantly decreased compared with the model group(P<0.05).CONCLUSION:EPDR1 is expressed in various tissues of wild-type mice,but showed diminished expression in the liver tissues of diabetic mice.Nevertheless,enhancing the expression of EPDR1 can aid in reducing lipid accumula-tion in hepatocytes.These findings provide an experimental foundation for further exploration of the role of EPDR1 in the development of fatty liver in diabetic liver tissue.

Objective To explore the changes and significane of USP20 and HIF-α expression in breast cancer.Methods Following transfection of shRNA-USP20 lentivirus into breast cancer MDA-MB-231 cells,the gene and protein expression levels of USP20 were detected using fluorescence quantitative PCR and Western Blot.Subsequently,the overexpression of USP20 was observed to determine its effect on HIF-α expression.Similarly,siRNA-USP20 was used to knock down USP20 in breast cancer MDA-MB-231 cells,followed by detection of gene and protein expression levels using fluorescence quantitative PCR and Western Blot.The subsequent changes in HIF-α expression were then examined.Rusults The positive expression rates of USP20 and HIF-α in breast cancer tissues were 69.6%and 46.83%,respectively,while they were negatively expressed in the adjacent normal tissues,with statistically significant differences(P＜0.01).The positive expressions of USP20 and HIF-α were predomi-nantly observed in the cytoplasm of breast cancer tissue,with a smaller amount present in the nucleus.There was a significant positive correlation between USP20 and HIF-α in breast cancer.Following transfection of shRNA-USP20 lentivirus into MDA-MB-231 cells,both the protein and gene expression levels of USP20 significantly increased(P＜0.01).Over-expression of USP20 did not affect HIF-α mRNA levels but led to a significant increase in HIF-α protein expression(P＜0.01).Conversely,siRNA-USP20 interference resulted in a significant decrease in both the protein and gene expression levels of USP20(P＜0.01),without affecting HIF-α mRNA levels;however,it caused a notable reduction in HIF-α protein expression(P＜0.01).Conclusion The expression of USP20 exhib-ited a significant positive correlation with HIF-α in breast cancer.Overexpression of USP20 led to a substantial increase in HIF-α protein expression,while knock-down of the USP20 gene resulted in a significant decrease in HIF-α protein levels.Therefore,it can be inferred that USP20 may exert its influence on the development of breast cancer through modulation of HIF-α expression,thereby providing crucial experimental evidence for clinical treat-ment,prognosis,and further investigations.

Objective To understand the serotype,molecular typing and drug sensitivity characteristics of Salmonella isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing.Methods A total of 71 Salmonella strains isolated from food and stool samples of diarrhea patients in Nan'an District of Chongqing from 2019 to 2022 were serotyped,and the drug resistance of the strains was determined by the micro-broth dilution method.Multilocus sequence typing(MLST)was performed on 2 Salmonella Ken-tucky strains,and whole genome sequencing was performed on 8 Salmonella typhimurium strains and 2 Sal-monella typhimurium variants.Results The 71 strains of Salmonella included 13 serotypes.A total of 48 Sal-monella strains were isolated from stool samples of diarrhea patients,with Salmonella typhimurium(56.25％,27/48)and Salmonella enteritidis(18.75％,9/48)as the main serotypes.A total of 23 Salmonella strains were isolated in food samples,with Salmonella Rissen(26.09％,6/23)as the predominant.The total drug re-sistance rate of 71 strains of Salmonella was 97.18％.The highest drug resistance rate was ampicillin(69.01％),followed by tetracycline(64.79％),compound sulfamethoxazole(43.66％)and chloramphenicol(43.66％).The multidrug resistant strains accounted for 61.97％(44/71),including 60.42％(29/48)of stool samples of diarrhea patients and 65.22％(15/23)of food samples.The two Salmonella Kentucky strains iso-lated from food and diarrhea patients were resistant to 7 and 8 types,respectively,with the largest number of drug resistant types in the corresponding samples.The MLST types of both Salmonella Kentucky strains was ST198 type.The MLST types of 8 Salmonella typhimurium strains selected for sequencing were ST19,and the MLST types of 2 Salmonella typhimurium monophasic variants were ST34.The genetic relationship of Salmo-nella typhimurium with the same ST type was different.Conclusion The serotypes of Salmonella isolated from Nan'an District of Chongqing are diverse and the drug resistance is serious.The detection of ST198 Sal-monella Kentucky is more accurate by using whole genome sequencing than MLST.The surveillance of Sal-monella serotypes,molecular typing and drug resistance should be strengthened.

Objective:To compare the application effect of domestic and imported intravenous radiofrequency closure system in the treatment of primary varicose veins of lower extremities.Methods:This single-center prospective, non-inferiority randomized controlled trial was performed in the Department of Vascular Surgery, the Fourth Affiliated Hospital, Zhejiang University School of Medicine from January 2021 to January 2022. Patients with primary varicose veins of lower extremities who met the ataxation criteria were randomly assigned to the experimental group(domestic novel venous radiofrequency closure system) or the control group(imported venous radiofrequency closure system) in a ratio of 1∶1. The two groups of subjects were compared in terms of target vein closure rate, technical success rate, system operation performance, incidence of adverse events and incidence of serious adverse events(SAE) within 6 months after surgery. Quantitative data were compared by Mann-Whitney U test, and categorical data were compared by χ2 test and non-inferiority test. Results:A total of 80 subjects were included in the trial (41 in the experimental group and 39 in the control group), including 27 males and 53 females, aged ( M(IQR)) 55(23) years (range:40 to 78 years). There were 48 cases of left lower limb and 32 cases of right lower limb. The technical success rate and system control performance between the groups were 100%.The incidence of adverse events (58.5% (24/41) vs. 61.5% (24/39), χ2=0.075, P=0.784), and the incidence of SAE (7.3% (3/41) vs. 5.1% (2/39), χ2=0.163, P=0.686) within 6 months after surgery in experimental group and control group had no statistical significance. There was one device-related adverse event in each of the two groups. In the experimental group, one patient developed endovenous heat-induced thrombosis after surgery and recovered after taking rivaroxaban tablets. One patient in the control group had pain in the upper right thigh for more than 1 day after operation, which was cured after using analgesic cream. No device-related SAE occurred. The venous closure rate of the experimental group was 100% (38/38) at 6 months after surgery, and that of the control group was 97.4% (37/38). The difference between the two groups was 2.63% (95% CI:-3.19 to 8.45, Z=4.865, P<0.01), and the 95% CI lower limit of the difference in target venous closure rate between two groups was greater than the non-inferiority threshold of -10.00%. Conclusion:The early application effect of the new domestic intravenous radiofrequency closure system in patients with primary varicose veins of lower extremities is in line with expectations, it is not inferior to the imported system.

Background Radiation-induced liver damage is a major complication for primary liver cancer and other upper abdominal tumors during radiation therapy. The early biological effects of radiation-induced liver damage at different doses of radiation and its mechanisms of action have not yet been elucidated. Objective To establish X-ray-induced radioactive mouse liver damage model and explore the level of oxidative stress and its correlation with nuclear factor-κB (NF-κB) and transforming growth factor-β1 (TGF-β1). Methods A total of 24 male C57BL/6J mice aged 6 weeks were randomly divided into 4 groups (control, 0.8 Gy, 1.6 Gy, and 4 Gy), with 6 mice in each group. X-rays irradiated the whole body of mice singly in each dose group. At 24 h after radiation, histopathological changes in mouse liver were evaluated; peripheral blood cell count, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels, as well as liver tissue superoxide dismutase (SOD) activity, malondialdehyde (MDA) level, reduced glutathione (GSH) level, and 8-hydroxy-2′-deoxyguanosine (8-OHdG) level were measured; real-time fluorescence quantitative PCR was used to detect liver tissue NF-κB p65 and TGF-β1 mRNA expression levels; the correlations of oxidative stress indicators with NF-κB p65 and TGF-β1 mRNA expression levels were analyzed by Pearson correlation. Results Compared with the control group, at 24 h after different doses of X-ray radiation, early injury-related histopathological changes were observed in liver, and the serum levels of AST and ALT were significantly increased in the 4 Gy group (P<0.05); the numbers of peripheral blood leukocytes and lymphocytes were decreased in the radiation exposure groups (P<0.05), showing a decreasing trend with increasing radiation doses; the levels of liver oxidative stress indicators (MDA, SOD, and GSH) in exposed mice were significantly increased (P<0.05), showing an increasing trend with increasing radiation doses. The liver 8-OHdG were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control and the 0.8 Gy groups, respectively (P<0.05). The NF-κB p65 and TGF-β1 mRNA expression levels in the liver of mice were significantly increased in the 1.6 Gy and 4 Gy groups compared with the control group (P<0.05). The TGF-β1 mRNA expression level also exhibited an increasing trend with increasing radiation doses. The results of correlation analysis showed that the levels of MDA, SOD, GSH, and 8-OHdG in liver tissues were significantly and positively correlated with the expression levels of NF-κB p65 and TGF-β1 mRNA (P<0.05). Conclusion X-rays of various doses can affect the degree of liver injury, peripheral blood cell count, serum levels of AST and ALT, and liver oxidative stress levels in mice. The level of oxidative stress induced by X-ray is positively correlated with NF-κB and TGF-β1 in liver tissues, and it may participate in the process of radiation-induced liver injury.

Objective To investigate the effects of lowdose ionizing radiation (LDIR) on oxidative stress and damage repair in human bronchial epithelial (HBE) cells. Methods HBE cells were divided into 0, 50, 100, and 200 mGy groups, and cultured for 24 and 48 h after X-ray irradiation, respectively. The cell viability, levels of glutathione (GSH), malondialdehyde (MDA), and 8-hydroxy-2’-deoxyguanosine (8-OHdG), and transcriptional levels of DNA damage repair genes PPP2R2D and TP53 were measured. Results At 24 h after irradiation, there was no significant difference in the cell viability between the dose groups and the control group (P > 0.05); all dose groups had significantly increased MDA level, dose-dependently decreased GSH level, dose-dependently increased 8-OHdG level, and significantly increased mRNA level of PPP2R2D gene (all P < 0.05); the mRNA expression level of TP53 gene was significantly increased in the 50 mGy group (P < 0.05). At 48 h after irradiation, there were the highest cell viability, significantly decreased MDA and 8-OHdG levels, and significantly increased mRNA expression levels of PPP2R2D and TP53 genes in the 50 mGy group compared with the control group (all P < 0.05); the GSH level in the 100 mGy group was significantly increased (P < 0.05). Conclusion LDIR, especially radiation at 50 mGy, can affect the oxidative-antioxidant level in HBE cells and the transcript-level differential expression of DNA damage repair genes.