1.Preparation and characterization of 3D plant-based scaffold based on decellularization method in liver tissue engineering
Jingjing HU ; Songlin HE ; Daxu ZHANG ; Shuo ZHAO ; Xiaonan SHI ; Weilong LI ; Shujun YE ; Jingyi WANG ; Quanyi GUO ; Li YAN
Chinese Journal of Tissue Engineering Research 2024;28(29):4645-4651
BACKGROUND:Tissue engineering has brought new hope to the clinical challenge of liver failure,and the preparation of plant-derived decellularized fiber scaffolds holds significant importance in liver tissue engineering. OBJECTIVE:To prepare apple tissue decellularized scaffold material by using fresh apple slices and a solution of sodium dodecyl sulfate,and assess its biocompatibility. METHODS:Fresh apples were subjected to decellularization using phosphate buffer saline and sodium dodecyl sulfate solution,separately.Afterwards,the decellularized apple tissues and apple decellularized scaffold materials were decontaminated with phosphate buffer saline.Subsequently,scanning electron microscopy was used to assess the effectiveness of decellularization of the apple materials.Adipose-derived mesenchymal stem cells were extracted from the inguinal fat BALB/C of mice,and their expression of stem cell-related markers(CD45,CD34,CD73,CD90,and CD105)was identified through flow cytometry.The cells were then divided into a scaffold-free control group and a scaffold group.Equal amounts of adipose-derived mesenchymal stem cells were seeded onto both groups.The biocompatibility of the decellularized scaffold with adipose-derived mesenchymal stem cells was evaluated using CCK-8 assay,hematoxylin-eosin staining,and phalloidine staining.Cell adhesion and growth on the scaffold were observed under light microscopy and scanning electron microscopy.Furthermore,the scaffold was subdivided into the non-induced group and the hepatogenic-induced group.Adipose-derived mesenchymal stem cells were cultured on the decellularized apple scaffold,and they were cultured for 14 days in regular culture medium or hepatogenic induction medium for comparison.Immunofluorescent staining using liver cell markers,including albumin,cytokeratin 18,and CYP1A1,was performed.Enzyme-linked immunosorbent assay was used to detect the secretion of alpha fetoprotein and albumin.Additionally,scanning electron microscopy was employed to observe the morphology of the induced cells on the scaffold,verifying the expression of liver cell-related genes on the decellularized scaffold material.Finally,the cobalt-60 irradiated and sterilized decellularized apple scaffolds were transplanted onto the surface of mouse liver and the degradation of the scaffold was observed by gross observation and hematoxylin-eosin staining after 28 days. RESULTS AND CONCLUSION:(1)The scanning electron microscopy results revealed that the decellularized apple scaffold material retained a porous structure of approximately 100 μm in size,with no residual cells observed.(2)Through flow cytometry analysis,the cultured cells were identified as adipose-derived mesenchymal stem cells.(3)CCK-8 assay results demonstrated that the prepared decellularized apple tissue scaffold material exhibited no cytotoxicity.Hematoxylin-eosin staining and phalloidine staining showed that adipose-derived mesenchymal stem cells were capable of adhering and proliferating on the decellularized apple tissue scaffold.(4)The results obtained from immunofluorescence staining and enzyme-linked immunosorbent assay revealed that adipose-derived mesenchymal stem cells cultured on the decellularized apple scaffolds exhibited elevated expression of liver-specific proteins,including albumin,alpha-fetoprotein,cytokeratin 18,and CYP1A1.These results suggested that they were induced differentiation into hepatocyte-like cells possessing functional characteristics of liver cells.(5)The decellularized apple scaffold implanted at 7 days has integrated with the liver,with partial degradation of the scaffold observed.By 28 days,the decellularized apple scaffold has completely degraded and has been replaced by newly-formed tissue.(6)The results indicate that the decellularized scaffold material derived from apple tissue demonstrates favorable biocompatibility,promoting the proliferation,adhesion,and hepatic differentiation of adipose-derived mesenchymal stem cells.
2.Therapeutic Effect of Bushen Huoxue Prescription on Diuretic Resistance in Chronic Heart Failure
Yuchen SUN ; Yan ZHANG ; Wenhao YIN ; Shujun ZHAO ; Muchen ZHANG ; Guohua LIU ; Yaqin WANG ; Yilin ZHAO
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(21):123-129
ObjectiveTo investigate the effects of Bushen Huoxue prescription on the cardiac function, inflammation, and quality of life of the patients with chronic heart failure resistant to diuretics. MethodA total of 78 patients who met the inclusion criteria were randomized into observation and control groups (39 cases). Both groups received standardized treatment for diuretic resistance in accordance with the guidelines. In addition, the observation group received Bushen Huoxue prescription. The cardiac function indicators, total response rate regarding symptom alleviation, exercise endurance, urine volume, body mass, quality of life, and levels of inflammatory cytokines were compared between the two groups before and after treatment. ResultBefore treatment, the two groups of patients showed no significant differences in terms of 24 h urine volume, body mass, 6 minute walk test (6MWT), Minnesota Living with Heart Failure Questionnaire (MLHFQ) score, N-terminal pro-B-type natriuretic peptide (NT-proBNP) level, left ventricular ejection fraction (LVEF), stroke volume (SV), and serum levels of interleukin-6 (IL-6), interleukin-4 (IL-4), and tumor necrosis factor-alpha (TNF-α). After treatment, the observation group outperformed the control group in terms of the response rates regarding traditional Chinese medicine symptom scores and New York Heart Association (NYHA) grading of cardiac function (P<0.05). After treatment, the body mass, MLHFQ score, and IL-6, TNF-α, and NT-proBNP levels decreased in both groups (P<0.05, P<0.01), and the observation group showed more significant decreases than the control group (P<0.05, P<0.01). Both groups showed increases in 24-h urine volume, 6MWT, LVEF, SV, and IL-4 after treatment (P<0.05, P<0.01), and the observation group showed more significant increases than the control group (P<0.05, P<0.01). ConclusionThe combination of Bushen Huoxue prescription with standardized treatment is effective in ameliorating the clinical symptoms of the patients with chronic heart failure resistant to diuretics. Moreover, it alleviates diuretic resistance and improves the cardiac function without causing obvious adverse reactions.
3.Clinical Efficacy and Effect on Inflammatory Cytokines of Huangjin Shuangshen Jiawei Granules in Treating Patients with Postoperative Anxiety and Depression After PCI for Coronary Heart Disease
Muchen ZHANG ; Yuchen SUN ; Yaqin WANG ; Shujun ZHAO ; Sanchun TANG ; Ju YIN ; Yilin ZHAO ; Yan ZHANG
Chinese Journal of Experimental Traditional Medical Formulae 2024;30(21):138-144
ObjectiveTo explore the clinical efficacy of Huangjin Shuangshen Jiawei (HJSSJW) granules in treating postoperative anxiety and depression after percutaneous coronary intervention (PCI) for coronary heart disease and the effects of this medicine on inflammatory cytokines. MethodNinety-four patients diagnosed with anxiety and depression after PCI were randomized into observation and control groups (47 cases) by the double-blind method. On the basis of conventional Western medical treatment, the observation group was treated with HJSSJW granules for 12 weeks, and the control group with the simulant of HJSSJW granules for 12 weeks. The two groups were compared in terms of Hamilton Anxiety and Depression Scales (HAMA-14, HAMD-24), Pittsburgh Sleep Quality Inventory (PSQI), Seattle Angina Score (SAQ), TCM symptom scores, traditional Chinese medicine (TCM) symptom score and response rate, serum levels of hypersensitive-C reactive protein (hs-CPR), tumor necrosis factor (TNF)-α, and interleukin (IL-6), and incidence of major adverse cardiovascular events (MACEs) and adverse reactions. ResultAfter treatment, both groups showed declined scores of HAMA-14, HAMD-24, and PSQI (P<0.05, P<0.01) and the observation group had lower scores of HAMA-14, HAMD-24, and PSQI than the control group (P<0.01). The scores of SAQ in both groups increased after treatment (P<0.01), and the observation group had higher score of each dimension than the control group (P<0.05). The TCM symptom scores decreased in both groups after treatment (P<0.01), and they were lower in the observation group than in the control group (P<0.05). The total response rate regarding TCM symptoms in the observation group was higher than that in the control group (χ2=9.225, P<0.01). After treatment, the levels of hs-CPR, IL-6, and TNF-α became lowered in both groups (P<0.01), and the observation group had lower levels of hs-CPR, IL-6, and TNF-α than the control group (P<0.05). The incidence of MACEs in the observation group was lower than that in the control group during the 90 d of the follow-up period (χ2=4.242, P<0.05). No adverse reactions associated with the use of HJSSJW granules were observed during the trial period. ConclusionHJSSJW granules can alleviate the bad mood, improve sleep, mitigate somatic symptoms, improve the quality of life, reduce inflammatory damage, and improve prognosis, being safe for clinical use in patients with postoperative anxiety and depression after PCI for coronary heart disease.
4.Traceability of a cluster outbreak of human brucellosis in Yantai City, Shandong Province in 2022
Yifan YU ; Yan LI ; Shujun DING ; Zengqiang KOU ; Weifeng SHI
Chinese Journal of Endemiology 2024;43(5):345-349
Objective:To investigate the potential source of infection for a cluster outbreak of human brucellosis in Yantai City, Shandong Province.Methods:The information of a human brucellosis cluster outbreak case in Yantai City, Shandong Province in 2022 was collected, the strains were isolated and cultured, and DNA was extracted. BCSP31-PCR was used for species identification, and AMOS-PCR was used for species type identification. Multiple locus variable-number tandem-repeat analysis (MLVA)-16 was used for clustering analysis, and the results were compared with the public database MLVAbank and the monitoring data of Brucella in Shandong Province in 2022. At the same time, whole genome single nucleotide polymorphism (wgSNP) typing was used to analyze the 53 Brucella strains that had completed whole genome sequencing in Shandong Province in 2022, and the wgSNP phylogenetic tree was constructed. Results:According to BCSP31-PCR and AMOS-PCR identification, the three strains related to the cluster outbreak of brucellosis in Yantai City, Shandong Province in 2022 were all Brucella melitensis biotype. The results of MLVA-16 typing showed that the MLVA-16 typing of the three isolated strains was completely consistent, with 16 tandem repeat loci of 1-5-3-13-2-2-3-2-4-41-8-4-4-3-6-5, belonging to the Eastern Mediterranean clade. Compared with MLVAbank, the MLVA-16 typing of two strains isolated from Kazakhstan was consistent with the results of this study. Compared with the monitoring data of Brucella in Shandong Province in 2022, it was found that the MLVA-16 typing of 11 isolated strains was consistent with the results of this study, which were isolated from Zaozhuang, Linyi, Taian, Yantai, and Weifang cities, respectively. The results of wgSNP typing showed that the distance between the 11 strains and the strains of the current outbreak was less than 7 single nucleotide polymorphisms, and the strains were isolated from Taian, Zibo, Linyi, Binzhou, Jinan, Jining, Yantai and Weihai cities, respectively. Conclusion:After tracing the source of a human brucellosis cluster outbreak in Yantai City, Shandong Province in 2022, it is speculated that the strains of Brucella melitensis isolated from Linyi, Taian and Yantai cities are closely related, indicating that sheep in these areas have homology.
5.The change trend analysis of incidence of intracerebral hemorrhage in Tengzhou City,Shandong Province from 2013 to 2021
Xin WANG ; Jinghua FAN ; Yuluan XU ; Nana YAN ; Xianli SONG ; Wen HUANG ; Li CHENG ; Liyu ZHOU ; Hongyu ZHU ; Shujun YE ; Zongyi WU ; Fengping ZHAO ; Fuzhong SI
Chinese Journal of Neurology 2023;56(7):770-779
Objective:To analyze the changing trend of intracerebral hemorrhage (ICH) incidence among residents with different characteristics during 9 years of comprehensive hypertension prevention and control (hypertension prevention and control) in Tengzhou from 2013 to 2021.Methods:From January 1, 2013 to December 31, 2021, the new ICH cases collected by the Center for Disease Control and Prevention in Tengzhou City were analyzed to calculate the incidence of ICH, and the trend of its distribution was analyzed among residents with different ages, sexes, and between urban and rural areas. The registered population information came from Tengzhou Public Security Bureau. Age and sex standardized incidence was calculated based on the 7th National Population Census in 2020. The Cochran-Armitage test was used to analyze the time and age trends of the incidence.Results:The overall ICH crude and standardized incidence in Tengzhou City decreased from 97.30/100 000 to 52.13/100 000 ( Z=-9.93, P<0.001) and 119.30/100 000 to 50.69/100 000 ( Z=-15.40, P<0.001) from 2013 to 2021, and both elevated to form a single peak in 2020, with 22.58% ( χ 2=24.02, P<0.001) and 18.09% ( χ 2=17.08, P<0.001) higher than in 2019, respectively. The trends in male and female incidence over the same period were similar to the overall trends, and the incidence was higher in males than in females in all years. The incidence of ICH increased with age in all years. The difference of increase in male incidence rate in 2020 was statistically significant in three age groups ≥45 years compared with 2019 (36.29%, 23.57% and 16.18%, respectively, χ 2=6.73, 4.65, 4.00, P<0.001). The incidence of ICH decreased by 70.07% and 36.23% ( Z=18.44, 5.22, P<0.001) in urban and rural areas respectively from 2013 to 2021, whereas increased by 34.15% ( χ 2=10.88, P<0.01) and 22.08% ( χ 2=18.63, P<0.001) in 2020 compared with 2019 separately. Conclusions:The incidence of ICH in Tengzhou from 2013 to 2021 showed a significant downward trend, with the decrease in the incidence of ICH in women exceeding that in men. The decrease in the incidence of ICH in urban areas exceeded that in rural areas, and male morbidity seemingly had a younger trend.
6.An investigation and analysis on multidimensional health status of the rural elderly in Shandong
Shujun WANG ; Shangxin LIU ; Jing SHI ; Jiahui YAN ; Jixiang MA ; Liangxia CHEN ; Pulin YU ; Baiyu ZHOU
Chinese Journal of Geriatrics 2023;42(5):570-575
Objective:To evaluate and analyze the health status of the elderly from physical health, mental health and social health, so as to understand the health status and health service needs of rural elderly.Methods:A total of 263 elderly people aged 60 years and over(mean aged 70.9±7.9 years, 113 males and 150 females, 125 aged 60-69 years, 98 aged 70-79 years and 40 aged 80 years and over)in Nanwangkong Village, Shaozhuang Town, Qingzhou City, Weifang City, Shandong Province were selected by cluster sampling method.The physical, mental, social and overall health status of the elderly were comprehensively evaluated and analyzed by self-designed questionnaire.Results:The overall health rate was 30%(79 cases), and the physical health, mental health and social health rates were 73.8%(194 cases), 84.0%(221 cases)and 34.6%(91 cases), respectively, in rural elderly in this area.The physical health was better in males than in females in 80~ years old groups( χ2=5.736, P<0.05). The overall health was better in males than in females in the total age group and the 60~69 years old groups( χ2=7.468 and 11.116, both P<0.01). The proportions of unhealthy, basic healthy and healthy people in the overall and the dimensions of physical health, mental health and social health had significant differences in the 60~69, 70~79 and 80~ years old groups( χ2=40.590, 29.342, 18.503 and 27.615, all P<0.01), and the Chi-square test for trend showed that there was a statistically significant downward trend of overall health grade distribution with age( χ2=21.994, 12.831, 16.570 and 22.595, both P<0.01). Conclusions:In this study, 30.0% of the rural elderly were considered healthy, 48.3% were basically healthy, and 21.7% were unhealthy.The health status of the elderly gradually deteriorates with age.The government should strengthen the multidimensional health assessment of the rural elderly and provide the comprehensive health guidance services and targeted interventions for the elderly in terms of disease control, psychological counseling and social participation.
7.Application of virtual training system for composite resin filling technique in undergraduate stomatology teaching
Shujun RAN ; Qiongyi KANG ; Jia WANG ; Yan ZOU ; Zhengwei HUANG ; Feng QIN
Chinese Journal of Medical Education Research 2023;22(12):1772-1776
Objective:To assess the influence of a virtual simulation-based training system for composite resin filling on the knowledge acquisition, skill development, and overall learning experience of undergraduate stomatology students.Methods:Forty-one undergraduate students of grade 2019 majoring in stomatology were divided into two groups for preclinical training before their internships: the experimental group used a virtual training system for composite resin filling, while the control group watched instructional videos of the procedure. The two groups were compared for their first performance in composite resin filling during the internships and teaching feedback. The t-test and chi-square test were conducted for data analysis using SPSS 20.0. Results:After repeatedly using the virtual training system for composite resin filling, the students in the experimental group were able to master the key operational points of the procedure, all achieving high scores (an average of 91.77 points) with an average time of 10.39 minutes. During the internship phase, the experimental group and control group showed significant differences in the accuracy rates of instrument selection (85.71% vs. 40.00%), adhesive applying (76.19% vs. 45.00%), and layered filling (100.00% vs. 75.00%; all P<0.05). All the students unanimously recognized the value of the virtual simulation system and expressed their willingness to use it for preclinical training before internships. Nineteen students (90.48%) were satisfied with the learning experience with the virtual simulation training system. Conclusions:The virtual simulation training system for composite resin filling can improve students' understanding and proficiency levels of the technique before clinical internships, facilitating a smoother transition to the internship phase.
8.A cross-sectional survey on the allocation of nursing human resources in burn centers in China
Shujun WANG ; Fangrong LI ; Hongyan LU ; Yuanyuan CHEN ; Xinzhu LIU ; Lihua CHEN ; Yanhua WANG ; Ziqing YAN ; Ping FENG ; Ying WU ; Yan ZHANG ; Chuan'an SHEN
Chinese Journal of Burns 2023;39(4):364-370
Objective:To investigate the allocation of nursing human resources in burn centers in China.Methods:A cross-sectional survey was conducted. Using a self-designed questionnaire, a survey was carried out from January to March 2022 to investigate the January to December 2021 status of 39 burn centers in China that met the inclusion criteria based on six strategic regions and other regions, including the hospital grade and the region, the number of nurses and opening beds in the burn centers and burn intensive care units (BICUs), the age, working seniority in burn specialty, educational background, professional title, personnel employment, and turnover of nurses and training of newly recruited nurses in the burn centers.Results:This survey covered 30 provinces, municipalities, and autonomous regions in China (excluding Hong Kong Special Administrative Region, Macao Special Administrative Region, and Taiwan region of China). A total of 39 questionnaires were collected, all of which were valid. The 39 burn centers were located in 38 tertiary A hospitals and 1 tertiary B hospital, with 26 burn centers in strategic areas. The nurse/bed ratio of burn centers in the Greater Bay Area of Guangdong, Hong Kong, and Macao was the highest, while the nurse/bed ratio of burn centers in border ethnic minority area was the lowest. Except for the Chengdu-Chongqing Economic Circle, BICUs had been set up in burn centers in other regions. Among the 39 burn centers, the percentage of nurses aged 25 to 34 years was 51.21% (738/1 441), the percentage of nurses worked in burn specialty for less than 5 years was 31.16% (449/1 441), the percentage of nurses with bachelor's degree was 69.74% (1 005/1 441), and the percentage of nurses with nursing professional title was 44.14% (636/1 441), which were the highest. There were significant differences in the employment of nurses, the percentage of permanent nurses in burn centers in the collaborative development zone of Beijing-Tianjin-Hebei was 82.48% (113/137), while the percentage of permanent nurses in burn centers in important military strategic area was only 9.42% (34/361); the turnover rate of nurses was 9.03% (143/1 584), among which the turnover rate of nurses was 18.14% (80/441) in burn centers in important military strategic area. The training for newly recruited nurses in 39 burn centers was mainly based on the guidance of senior nurses and the pre-job education+specialist training.Conclusions:The burn nursing human resources in strategic areas in China are seriously insufficient and unevenly distributed, with unstable nurse team and lack of standardized specialist training. In particular, the nursing human resources in BICUs need to be equipped and supplemented urgently.
9.Epidemiological characteristics and spatial clustering analysis of brucellosis in Shandong Province from 2015 to 2020
Xiaolin YU ; Ming FANG ; Yan LI ; Kaijun FENG ; Shujun DING ; Zengqiang KOU
Chinese Journal of Endemiology 2022;41(9):750-755
Objective:To learn about the epidemiological and spatial clustering characteristics of brucellosis in Shandong Province, and to provide a reference for scientific prevention and control of brucellosis.Methods:The epidemic data of human brucellosis in Shandong Province from January 2015 to December 2020 were collected from the Infectious Disease Reporting Information Management System of China Disease Control and Prevention Information System, and the data were analyzed by descriptive epidemiology and spatial clustering analysis.Results:A total of 18 811 cases of human brucellosis were reported in Shandong Province from 2015 to 2020, and the average annual incidence rate was 3.16/100 000. Human brucellosis occurred in every month of the year, and the peak incidence was from March to August, accounting for 66.31% (12 474/18 811). The top 5 counties (districts) with average annual incidence rates were Lijin County (32.39/100 000), Kenli District (11.02/100 000), Wudi County (10.35/100 000), Zhanhua District (9.59/100 000) and Shanghe County (8.80/100 000). There were 13 436 males and 5 375 females, with a male-female sex ratio of 2.50 ∶ 1.00; the age was mainly concentrated in 30-69 years old, accounting for 83.23% (15 656/18 811); farmer was the main occupation, accounting for 85.82% (16 144/18 811). The results of global spatial autocorrelation analysis showed that the annual incidence rates of brucellosis in Shandong Province showed a spatial clustering distribution from 2015 to 2020; and the local spatial autocorrelation analysis showed that the high incidence of human brucellosis was mainly concentrated in the north of Shandong Province.Conclusions:The incidence of brucellosis in Shandong Province is mainly concentrated in spring and summer, most of them are farmers, and the high incidence areas have spatial clustering. Key prevention and control measures should be taken for high incidence seasons, high-risk population and northern high clustering areas to reduce the incidence of brucellosis.
10.Analysis on risk factors of nosocomial multi-drug resistant bacteria infection of wounds in orthopedic trauma patients
Zeqiong ZHANG ; Ganshan TAN ; Shujun WANG ; Qian NING ; Lingxiao HE ; Dengbin LIAO ; Yan JIANG
Chinese Journal of Trauma 2021;37(8):726-732
Objective:To investigate the risk factors of multi-drug resistant organism(MDRO)infection in orthopedic trauma patients.Methods:A retrospective case series study was made on clinical data of 95 orthopedic patients with in-hospital wound infection admitted to West China Hospital of Sichuan University from January 2020 to December 2020,including 71 males and 24 females at age of 14-70 years[(42.6 ± 13.8)years]. MDRO infection occurred in 38 patients(DRO group),while not in 57 patients(non-MDRO group). Etiological characteristics of wound infections were observed. Univariate analysis was used to compare variables between the two groups,including baseline data(gender,age,length of hospital stay,chronic comorbidity)and injury as well as hospitalization information(transfer from another hospital,emergency admission,time from injury to first treatment,open injury,combination with fracture,wound contamination,depth of wound,ICU stay,number of operations,cumulative operation time,type of incision,length of hospital stay before diagnosis of infection,type of antibiotics used,usage of hormones/immunosuppressive agents,level of hemoglobin/serum albumin/blood glucose on admission). Binary Logistic regression was used to analyze independent risk factors for MDRO infection.Results:A total of 119 pathogenic bacteria were detected on the wound,including 21 gram-positive cocci(18%),91 gram-negative bacilli(76%)and 7 others(6%). Top five strains were Acinetobacter baumannii,Enterobacter cloacae,Escherichia coli,Staphylococcus aureus and Pseudomonas aeruginosa. Univariate analysis showed the two groups had significant differences in terms of length of hospital stay,wound contamination,ICU stay,length of hospital stay before diagnosis of infection,type of antibiotics used and levels of hemoglobin and serum albumin on admission( P < 0.05),but not in gender,age,hypertension,diabetes,transfer from another hospital and emergency admission( P > 0.05). Multivariate Logistic regression analysis showed MDRD infection was obviously correlated with the long hospital stay( OR = 1.033, 95%CI 1.005-1.061, P < 0.05),time from injury to first treatment over 6 hours( OR = 4.282, 95%CI 1.174-15.616, P < 0.05),types of antibiotics used ≥ 3( OR = 7.486, 95%CI 2.451-22.863, P < 0.05)and low level of hemoglobin on admission( OR = 0.973, 95%CI 0.962-0.985, P < 0.05). Conclusions:For orthopedic trauma patients,MDRO infection is independently associated with long hospital stay,time from injury to first treatment,type of antibiotics use and level of hemoglobin on admission,suggesting that decreased length of hospitalization,shortened time of first wound treatment,individualized and rational usage of antibiotics and timely correction of anemia are important measures to prevent MDRO infection.

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