1.Exploring the mechanism of traditional Chinese medicine indirubin derivative E804 inhibiting the proliferation and migration of lung cancer A549 cells based on the Nrf2-HO-1/GPX4 pathway
Yujun YUAN ; Huahua CAO ; Min ZHAO ; Yuhui LUO ; Sumei ZHANG
Acta Universitatis Medicinalis Anhui 2024;59(2):331-335,343
Objective To investigate the effects of indirubatin derivative E804 on proliferation and migration of non-small cell lung cancer(NSCLC)A549 cells,and to elucidate the possible mechanism of Nrf2-HO-1/GPX4 pathway.Methods Lung cancer A549 cells were used as the cell model.The proliferation and migration of differ-ent specific inhibitors(Nec-1,CQ,Z-VAD,DFO,Fer-1 and Lip-1)in 0,10 μmol/L E804 and 10 μmol/L E804+groups were observed by MTT and cell scratch assay.The contents of reactive oxygen species(ROS)were de-tected by DCFH-DA fluorescence probe method,the contents of Fe2+were detected by colorimetric method,the contents of reduced glutathione(GSH)were detected by spectrophotometry,and the contents of malondialdehyde(MDA)were detected by micromethod.The expression levels of SLC7A11,Transferrin,GPX4,SLC40A1,Nrf2 and HO-1 were detected by Western blot in cells of 0,2.5,5 and 10 μmol/L E804 groups.Results Compared with the control group(0 μmol/L E804),2.5,5 and 10 μmol/L E804 significantly increased intracellular ROS,Fe2+and MDA levels,and decreased intracellular GSH content(P<0.01).Meanwhile,the expression levels of SLC7A11,GPX4,SLC40A1,Nrf2 and HO-1 significantly decreased(P<0.01),and the expression level of Transferrin increased(P<0.05).Compared with the 10 μmol/L E804 group alone,the apoptosis inhibitor(Z-VAD)group and the ferroptosis inhibitor(DFO,Fer-1 and Lip-1)group could significantly reverse the inhibition of proliferation and migration of A549 cells by 10 μmol/L E804(P<0.01).Conclution E804 can induce ferrop-tosis and inhibit the proliferation and migration of A549 cells,which may be related to the inhibition of Nrf2-HO-1/GPX4 pathway.
2.Correlation of triglyceride-glucose index with unfavorable outcomes following moderate-to-severe traumatic brain injury
Cheng CAO ; Haicheng XU ; Jiachen WANG ; Hongjie ZHAO ; Yuan SHI ; Yuzhou CHEN ; Wei WU ; Heng GAO
Chinese Journal of Trauma 2024;40(2):118-126
Objective:To investigate the correlation between triglyceride-glucose (TyG) index on admission and unfavorable outcomes of patients with moderate-to-severe traumatic brain injury (msTBI) at 6 months postinjury.Methods:A retrospective cohort study was conducted to analyze the clinical data of 277 patients with msTBI admitted to Affiliated Jiangyin Hospital of Nantong University from January 2019 to December 2022, including 208 males and 69 females, aged 18-88 years [(57.0±15.1)years]. Glasgow Coma Scale (GCS) scores on admission were 3-8 points in 168 patients and 9-12 points in 109. According to the Glasgow Outcome Scale-Extended (GOSE) assessment at 6 months after injury, there were 121 patients with unfavorable outcomes (GOSE≤4 points) and 156 with favorable outcomes (GOSE≥5 points). The following indicators of the patients were recorded, including gender, age, history of diabetes, cause of injury, admission GCS, GCS motor score (GCSM), pupillary light reflex, worst Marshall CT classification within the first 24 hours after admission, admission TyG index, Mean Amplitude of Glycemic Excursions (MAGE) within 24 hours after admission, GCSM decline≥2 points within 72 hours after admission, craniotomy or not after admission, and prognosis, etc. TyG index served as the exposure variable focused in this study, which was calculated with fasting triglycerides and fasting blood glucose within 24 hours after admission. The 6-month prognosis of the patients was designated as the outcome variable of the study. After the patients were divided into different groups according to the three quantiles of the TyG index and unfavorable or favorable outcomes, the univariate analysis was conducted on watch variables, and variables with statistically significant differences were included in directed acyclic graphs (DAGs) for further identification of confounding variables. Factors which were found with no statistical significance in the univariate analysis but might affect insulin resistance after injury according to the authors′ previous researches were also included in the DAGs analysis. Three Logistic regression models were designed (Model 1 without correction, Model 2 with core variables of International Mission for Prognosis and Analysis of Clinical Trials in Traumatic Brain Injury (IMPACT) corrected, and Model 3 with confounding variables screened by DAGs corrected) to analyze whether the TyG index was an independent risk factor for the prognosis of msTBI patients. The optimal Logistic regression model was selected and then restricted cubic spline (RCS) was employed to investigate the relationship between the TyG index and the unfavorable outcomes.Results:The univariate analysis suggested that there were significant differences in gender, history of diabetes, MAGE, GCSM decline, and prognosis among the three quantiles of the TyG index ( P<0.05 or 0.01). Significant differences in age, history of diabetes, GCSM, pupillary light reflex, Marshall CT classification, TyG index, MAGE and GCSM decline were observed between unfavorable and favorable outcome groups ( P<0.05 or 0.01). The results of Logistic regression analysis that identified the confounding variables that influenced the correlation between the TyG index and unfavorable prognosis with DAGs suggested that a high TyG index level was significantly correlated with unfavorable outcomes in msTBI patients. Moreover, Model 3 that was corrected with confounding variables screened by DAGs had an optimal goodness-of-fit and adaptability. Model 3-based further RCS analysis indicated that the risk of unfavorable outcomes following msTBI may increase approximately linearly with the increase in TyG index within a certain range (TyG index<9.79). Conclusions:A high TyG index level on admission is the identified as an independent risk factor for unfavorable outcomes of patients with msTBI at 6 months postinjury. As the TyG index level increases, the risk of unfavorable outcomes also rises and may show a linear increasing trend within a certain range (TyG index<9.79).
3.Pachymaran regulates pyroptosis of liver cancer cells via SQLE/NLRP3/GSDMD signaling pathway
Ying YANG ; Yuan CAO ; Jiao ZHAO ; Zheng LI ; Qun WANG ; Hao GAO ; Xiaofei SUN ; Mingdian YUAN ; Nan SONG
Chinese Journal of Pathophysiology 2024;40(3):444-455
AIM:Using bioinformatics analysis and experiment validation to explore the differential expres-sion genes related to abnormal lipid metabolism in hepatocellular carcinoma(HCC)and the molecular mechanism of pachymaran affecting pyroptosis through squalene epoxidase(SQLE)/nucleotide-binding oligomerization domain-like re-ceptor protein 3(NLRP3)/gasdermin D(GSDMD)signaling pathway.METHODS:(1)The GEO,GSEA,DAVID,STRING and GEPIA databases were employed to screen abnormal lipid metabolism-related differentially expressed genes in HCC.(2)The tumor tissues from HCC patients(n=9)were collected to verify the differential expression of SQLE.(3)The inhibitory effect of pachymaran on the viability of human HCC cell line HepG2 was measured by CCK-8 assay.(4)The HepG2 cells were divided into control group and pachymaran(800 mg/L)group.The cell migration was analyzed by wound-healing assay,and RT-qPCR was used to measure SQLE mRNA expression.(5)The HepG2 cells with overexpres-sion of SQLE(OE-SQLE)were divided into 5 groups as follows:control group,overexpression negative control(OE-NC)group,OE-SQLE group,OE-NC+pachymaran group,and OE-SQLE+pachymaran group.The mRNA and protein expres-sion levels of SQLE and pyroptosis-related factors were determined by RT-qPCR and Western blot.Colorimetric method and ELISA were used to measure lactate dehydrogenase(LDH),interleukin-1β(IL-1β)and IL-18 levels.The necrosis of HepG2 cells was analyzed by flow cytometry.RESULTS:The SQLE gene was screened through bioinformatics analysis,and its mRNA expression was significantly increased in tumor tissues from HCC patients(P<0.01).In cell experiments,treatment with 800 mg/L pachymaran for 48 h had a significant inhibitory effect on HepG2 cell viability,and the expres-sion of SQLE mRNA was reduced(P<0.01).After overexpression of SQLE,the mRNA and protein levels of pyroptosis-re-lated factors,necrotic rate,and LDH,IL-1β and IL-18 levels were significantly decreased(P<0.05).After treatment with pachymaran,the above indicators were significantly increased(P<0.05).CONCLUSION:The SQLE is abnormal-ly highly expressed in HCC,and pachymaran can affect the growth of HCC cells by activating the NLRP3/GSDMD pyropto-sis pathway through SQLE.
4.Simultaneous GC-MS determination of sixteen pesticide residues and safety assessment for Lycii Fructus
Jia-Qi QIN ; Qiang-Qiang QI ; Ya-Jun ZHANG ; Yan WANG ; Si-Yuan ZHAO ; De-Yan CAO ; Mei-Lin ZHU
Chinese Traditional Patent Medicine 2024;46(1):143-149
AIM To establish a GC-MS method for the simultaneous content determination of sixteen pesticide residues in Lycii Fructus and perform safety assessment.METHODS The analysis was performed on DB-5MS chromatographic column(30 m×0.25 mm,0.25 μm)subjected to the programmed heating,with splitless injection of 1.0 μL dissolved sample at a flowing rate of 1.0 mL/min.Other parameters were as follows:injection port temperature of 250℃,electron impact ionization(EI),electron energy of 70 eV;ion source temperature of 230℃,multi-reaction monitoring mode,and collision gas.of high-purity N2.Pesticide residues with relatively high dietary risk were analyzed and discussed with regard to residue levels,dietary intake risk,risk ranking and cumulative exposure assessment.RESULTS Sixteen pesticides showed good linear relationships within their own ranges(r≥0.994 4),whose average recoveries were 70%-114%,with the RSDs of less than 2%.The highest average cyfluthrin residue of 0.999 2 mg/kg in Lycii Fructus of production regions and the highest average cypermethrin residue of 0.088 4 mg/kg in Lycii Fructus commodities were both detected.In Lycii Fructus of production regions with chronic hazard index(HI)value of 0.012 9 and acute HI value of 0.065 5 and their commodities with chronic HI of 0.001 2 and acute HI of 0.005 4,the pesticide residue of cypermethrin was the leading cause of chronic and acute dietary risk,and additionally,pyridaben within maximum residue limit(MRL)was the only detectectable highly toxic pesticide among the other most concerning pestcides of deltamethrin,pyridaben,chlorpyrifos,dichlorvos and methidathion.CONCLUSION There exist pesticide residues within MRL values in some samples of Lycii Fructus and the use of cypermethrin should be well-controlled.
5.Shuxuetong Inhibits Bim-dependent Apoptosis of Cerebellar Granule Neurons
Shenhao PAN ; Dongfang CAO ; Fanyi ZHAO ; Sijie ZHAO ; Chenghao ZHANG ; Jianfeng LIANG ; Jianwei WU ; Zhongmin YUAN
Journal of Sun Yat-sen University(Medical Sciences) 2024;45(4):549-556
[Objective]To investigate the effect and mechanism of Shuxuetong and its main component hirudin on the apoptosis of cerebellar granule neurons(CGNs)in Sprague-Dawley(SD)rats.[Methods]CGNs incubated in vitro for 7 days were divided into survival control group or 25 K group(cultured in medium containing 25 mmol/L KCL)and apopto-sis group or 5 K group(cultured in medium containing 5 mmol/L KCL).CGNs were separately treated with proportionally diluted and different concentrations of Shuxuetong(1/50,1/40,1/30,1/20 and 1/10)and the corresponding different con-centrations of hirudin(2,2.5,3.34,5 and 10 U/mL).Hoechst staining was performed to analyze the apoptosis.Western blot was used to detect the expression levels of Cleaved Caspase-3,Bim and VEGF.[Results]Hoechst staining showed that 5 K group had a higher apoptosis rate than 25 K group.In 25 K group,there was no significant change in the apoptosis rate between neurons treated with different concentrations of Shuxuetong and hirudin,but significant changes was found in 5 K group and the higher the concentration,the lower the apoptosis rate.Western blot results revealed that,compared with control neurons in 5 K group,Shuxuetong injection and hirudin treatments resulted in a decrease of Cleaved Caspase-3 and Bim expression,but an increase of VEGF protein.[Conclusions]Shuxuetong and its main component hirudin inhibits the apoptosis of CGNs through suppressing proapoptotic BH3-only protein Bim.
6.Influencing factors of atrial fibrillation in patients with heart failure and analysis of family empower-ment mode strategy
Zhu-Mei CHEN ; Han-Li WEN ; Yuan CAO ; Ya LIU ; Fei YANG ; Qing ZHAO
Chinese Journal of cardiovascular Rehabilitation Medicine 2024;33(5):522-526
Objective:To explore the influencing factors of atrial fibrillation(AF)in patients with heart failure(HF)and the effects of family empowerment mode strategy.Methods:A total of 220 HF patients who were trea-ted in First Affiliated Hospital of Chinese PLA Air Force Military Medical University between April 2020 and March 2021 were selected.According to presence of AF or not,they were divided into AF group(n=80)and no AF group(n=140);patients in AF group received family empowerment mode strategy management for 3 months.Scores of self-care behavior scale and quality of life scale were compared between before and after intervention in AF group.Multivariate Logistic regression was used to analyze influencing factors of AF in HF patients,receiver operating characteristic(ROC)curve was used to analyze diagnostic value of above risk factors for AF in HF patients.Results:Compared with no AF group,patients in AF group had significant higher level of brain natriuretic peptide(BNP),left ventricular diameter and number of implanted stents(P<0.001 all).Multivariate Logistic regression indicated that BNP>400pg/ml,left ventricular diamcter>40mm and number of implanted stents>2 were independent risk factors for AF in HF patients(OR=1.349~2.501,P<0.01 all).ROC curve indicated that AUC of BNP,left ven-tricular diameter and number of implanted stents predicting AF in HF patients was 0.819,0.812 and 0.745 respec-tively,all of them had good diagnostic value.Compared with before intervention,there were significant rise in di-mensional scores of self-care maintenance,self-care management and self-care confidence of HF patient self-care behavior scale,and significant reductions in scores of physical domain,emotional domain and other domain of HF quality of life scale in AF group after 3-month intervention(P<0.001 all).Conclusion:BNP,left ventricular diameter and number of implanted stents are risk factors for atrial fibrillation in patients with heart failure.Self-management and quality of life significantly improve after family empowerment mode management in these patients.
7.Vaccarin alleviates mitochondrial damage and endothelial dysfunction in type 2 diabetes by regulating miR-570-3p/BNIP3 pathway
Chenyang ZHAO ; Xuexue ZHU ; Xinyu CHEN ; Tianxiao CHEN ; Jinpeng XU ; Tai-Yue LI ; Xingyu CAO ; Yuan ZHANG ; Liying QIU
Chinese Journal of Pathophysiology 2024;40(5):872-881
AIM:To investigate the effect of vaccarin(VAC)on endothelial dysfunction in type 2 diabetes mellitus(T2DM),and to uncover the underlying mechanisms.METHODS:(1)C57BL/6 mice received intraperitoneal injection of streptozotocin and were fed with a high-fat diet(21.8 kJ/kg,60%of the energy source was fat)to construct a T2DM mouse model.Thirty mice were randomly divided into control,T2DM and T2DM+VAC groups,with 10 mice in each group.The mice in T2DM+VAC group were given 1 mg/kg VAC via oral gavage for 6 weeks,while those in control and T2DM groups were given the same volume of PBS.The mRNA and protein expression levels of BCL2-interacting pro-tein 3(BNIP3),PTEN-induced kinase 1(PINK1)and parkin in the thoracic aorta were detected by RT-qPCR and West-ern blot.(2)Human umbilical vein endothelial cells(HUVECs)were stimulated by high glucose(HG;35 mmol/L glu-cose).Mitochondrial membrane potential,autophagy and mitochondrial superoxide levels were detected using JC-1,acri-dine orange(AO)and MitoSOX staining,respectively.RESULTS:Compared with control group,the mRNA and protein levels of BNIP3,PINK1 and parkin were significantly increased in the thoracic aorta of T2DM mice(P<0.05).Compared with T2DM group,the mRNA and protein levels of BNIP3,PINK1 and parkin in the thoracic aorta were significantly re-duced in T2DM+VAC group(P<0.05).The results of JC-1,AO and MitoSOX staining showed that VAC attenuated the decrease in mitochondrial membrane potential and the increase in autophagy and mitochondrial superoxide levels in HG-in-duced HUVECs.Treatment with VAC also inhibited HG-mediated mitochondrial damage in HUVECs after BNIP3 overex-pression.The effect of miR-570-3p mimic on mitochondrial damage was similar to VAC.RT-qPCR and Western blot showed that both miR-570-3p mimic and VAC significantly reduced the mRNA and protein levels of BNIP3,PINK1 and parkin.In contrast,inhibition of miR-570-3p exhibited the opposite effects.CONCLUSION:Treatment with VAC alle-viated endothelial dysfunction in T2DM by inhibiting HG-induced mitochondrial dysfunction through miR-570-3p/BNIP3.
8.A multi-center epidemiological study on pneumococcal meningitis in children from 2019 to 2020
Cai-Yun WANG ; Hong-Mei XU ; Gang LIU ; Jing LIU ; Hui YU ; Bi-Quan CHEN ; Guo ZHENG ; Min SHU ; Li-Jun DU ; Zhi-Wei XU ; Li-Su HUANG ; Hai-Bo LI ; Dong WANG ; Song-Ting BAI ; Qing-Wen SHAN ; Chun-Hui ZHU ; Jian-Mei TIAN ; Jian-Hua HAO ; Ai-Wei LIN ; Dao-Jiong LIN ; Jin-Zhun WU ; Xin-Hua ZHANG ; Qing CAO ; Zhong-Bin TAO ; Yuan CHEN ; Guo-Long ZHU ; Ping XUE ; Zheng-Zhen TANG ; Xue-Wen SU ; Zheng-Hai QU ; Shi-Yong ZHAO ; Lin PANG ; Hui-Ling DENG ; Sai-Nan SHU ; Ying-Hu CHEN
Chinese Journal of Contemporary Pediatrics 2024;26(2):131-138
Objective To investigate the clinical characteristics and prognosis of pneumococcal meningitis(PM),and drug sensitivity of Streptococcus pneumoniae(SP)isolates in Chinese children.Methods A retrospective analysis was conducted on clinical information,laboratory data,and microbiological data of 160 hospitalized children under 15 years old with PM from January 2019 to December 2020 in 33 tertiary hospitals across the country.Results Among the 160 children with PM,there were 103 males and 57 females.The age ranged from 15 days to 15 years,with 109 cases(68.1% )aged 3 months to under 3 years.SP strains were isolated from 95 cases(59.4% )in cerebrospinal fluid cultures and from 57 cases(35.6% )in blood cultures.The positive rates of SP detection by cerebrospinal fluid metagenomic next-generation sequencing and cerebrospinal fluid SP antigen testing were 40% (35/87)and 27% (21/78),respectively.Fifty-five cases(34.4% )had one or more risk factors for purulent meningitis,113 cases(70.6% )had one or more extra-cranial infectious foci,and 18 cases(11.3% )had underlying diseases.The most common clinical symptoms were fever(147 cases,91.9% ),followed by lethargy(98 cases,61.3% )and vomiting(61 cases,38.1% ).Sixty-nine cases(43.1% )experienced intracranial complications during hospitalization,with subdural effusion and/or empyema being the most common complication[43 cases(26.9% )],followed by hydrocephalus in 24 cases(15.0% ),brain abscess in 23 cases(14.4% ),and cerebral hemorrhage in 8 cases(5.0% ).Subdural effusion and/or empyema and hydrocephalus mainly occurred in children under 1 year old,with rates of 91% (39/43)and 83% (20/24),respectively.SP strains exhibited complete sensitivity to vancomycin(100% ,75/75),linezolid(100% ,56/56),and meropenem(100% ,6/6).High sensitivity rates were also observed for levofloxacin(81% ,22/27),moxifloxacin(82% ,14/17),rifampicin(96% ,25/26),and chloramphenicol(91% ,21/23).However,low sensitivity rates were found for penicillin(16% ,11/68)and clindamycin(6% ,1/17),and SP strains were completely resistant to erythromycin(100% ,31/31).The rates of discharge with cure and improvement were 22.5% (36/160)and 66.2% (106/160),respectively,while 18 cases(11.3% )had adverse outcomes.Conclusions Pediatric PM is more common in children aged 3 months to under 3 years.Intracranial complications are more frequently observed in children under 1 year old.Fever is the most common clinical manifestation of PM,and subdural effusion/emphysema and hydrocephalus are the most frequent complications.Non-culture detection methods for cerebrospinal fluid can improve pathogen detection rates.Adverse outcomes can be noted in more than 10% of PM cases.SP strains are high sensitivity to vancomycin,linezolid,meropenem,levofloxacin,moxifloxacin,rifampicin,and chloramphenicol.[Chinese Journal of Contemporary Pediatrics,2024,26(2):131-138]
9.Progress of research on MHC function and transgenic mouse models
Xiangwen CAO ; Min LI ; Qi YIN ; Xuelian HAN ; Yuan WANG ; Guangyu ZHAO
Chinese Journal of Comparative Medicine 2024;34(6):151-160
The major histocompatibility complex(MHC)is closely related to immune regulation.MHC shows distinct genetic polymorphism,and there are also species differences in MHC restriction.The human MHC is called human leukocyte antigen(HLA),and the mouse MHC is called H-2.The construction of humanized MHC transgenic mouse models is an important strategy to overcome the differences in MHC among species and simulate the characteristics of a human immune response.MHC transgenic mice are mainly divided into MHC Ⅰ or MHC Ⅱ single-transgenic mouse models and MHC Ⅰ and MHC Ⅱ double-transgenic mouse models.The development of HLA Ⅰ transgenic mouse model went through three stages,at present,the strategy of knocking out H-2Kb and H-2Db or murine β2m is adopted to eliminate the competitive inhibition of HLA Ⅰ molecules by endogenous H-2 class Ⅰ molecules.In the construction of an HLA Ⅱtransgenic mouse model,the β strand of murine origin is knocked out and HLA Ⅱ class genes are inserted.With the optimization of construction strategies,MHC transgenic mouse models have been applied to epitope vaccine development,tumor treatment,and genetic disease-association studies,becoming a powerful tool for preclinical trials.In this paper,we summarize the relevant data on MHC transgenic mouse models,as well as the construction strategies used for MHC transgenic mouse models and their application in vaccine development and disease treatment.
10.Effect of total flavonoids of Dracocephalum moldavica on TMAO-mediated JAK/STAT axis against atherosclerosis in rats and inflammation in RAW264.7 cells
Wen-Jiang CAO ; Chun-Yan DU ; Chuan-Sheng HUANG ; Yun-Li ZHAO ; Xiao-Li MA ; Yong YUAN ; Xin-Chun WANG
Chinese Pharmacological Bulletin 2024;40(9):1766-1772
Aim To investigate the protective effect of total flavonoids of Dracocephalum moldavica(TFDM)on atherosclerosis in rats and the inflammation of mouse macrophage RAW264.7 aggravated by trimeth-ylamine N-oxide(TMAO)and its possible mecha-nism.Methods The AS model of SD rats was estab-lished by high-fat diet feeding combined with intraper-itoneal injection of vitamin D3.The rats were divided into control group,model group,simvastatin group(15 mg·kg-1)and TFDM group(60,30,15 mg·kg-1).Biochemical method was used to detect the levels of se-rum total cholesterol(TC),triglyceride(TG)and low density lipoprotein cholesterol(LDL-C).HE staining was used to detect the pathological changes of aortic tissue.ELISA kit was used to detect the expression of TMAO,IL-1β,IL-6 in serum and TNF-α in liver tis-sue.Western blot was used to detect the expression of JAK,STAT and TNF-α protein in aorta.In addition,RAW264.7 macrophages were cultured in vitro,and LPS+TMAO was used to establish a macrophage in-flammation model,which was intervened by TFDM(100,50,25 mg·L-1).CCK-8 was used to determine cell viability and proliferation,and RT-qPCR was used to detect the expression of TNF-α,IL-6,JAK and STAT mRNA in cells.Results TFDM could significantly down-regulate the levels of serum TC,TG,LDL-C,ser-um TMAO,IL-1β,IL-6 and liver TNF-α,reduce aortic plaque deposition,and down-regulate the protein ex-pression of TNF-α,JAK and STAT in aorta.In addi-tion,TFDM intervention can significantly down-regulate the expression of TNF-α,IL-6,JAK,STAT mRNA and the expression of JAK,STAT protein.Conclusion TFDM can reduce the content of TMAO in serum,in-hibit JAK/STAT inflammatory signaling pathway and slow down the occurrence of inflammation,playing an anti-AS role.

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