1.Application of single-cell RNA sequencing technology in Parkinson's disease
Ziyu LIU ; Dandan GENG ; Runjiao ZHANG ; Qing LIU ; Yibo LI ; Hongfang WANG ; Wenmeng XIE ; Wenyu WANG ; Jiaxin HAO ; Lei WANG
Chinese Journal of Tissue Engineering Research 2025;29(1):193-201
BACKGROUND:Parkinson's disease has the main pathological changes in the midbrain,especially in the dense substantia nigra,leading to impaired motor and non-motor function in patients.At present,research is limited by cellular heterogeneity,and its pathogenesis still needs to be further elucidated.In recent years,single-cell RNA sequencing(scRNA-seq)has gradually been applied in neurodegenerative diseases,which is of great significance for understanding intercellular heterogeneity,disease development mechanisms,and treatment strategies. OBJECTIVE:To review the research progress of scRNA-seq technology applied to Parkinson's disease in recent years,providing a theoretical basis for the application of scRNA-seq in the treatment and diagnosis of Parkinson's disease. METHODS:The first author used a computer system to search for relevant literature in the CNKI,WanFang,PubMed,and Web of Science databases,with the Chinese search terms"single-cell RNA sequencing,Parkinson's disease,cell heterogeneity,cell subtypes,dopaminergic neurons,glial cells"and English search terms"single-cell RNA seq,Parkinson disease,heterogenicity,subtypes,dopaminergic neurons,glial cells."71 articles were ultimately included for review and analysis. RESULTS AND CONCLUSION:(1)scRNA-seq is a high-throughput experimental technique that utilizes RNA sequencing at the single-cell level to quantify gene expression profiles in specific cell populations,revealing cellular mysteries at the molecular level.Compared with traditional sequencing techniques,scRNA-seq technology is used to reveal the diversity of cell types and changes in specific gene expression in complex tissues under various physiological and pathological conditions through automatic clustering analysis of cell transcriptome.(2)By using scRNA-seq,the development process of dopaminergic neurons and the unique functional characteristics of various cell subtypes are elucidated,in order to better understand potential therapeutic molecular targets.(3)The use of scRNA-seq analysis has improved our understanding of the response of Parkinson's disease glial cells,enabling us to comprehensively map and characterize different cell type populations,identify specific glial cell subpopulations related to neurodegeneration,and draw valuable single cell maps as reference data for future research.(4)The application of scRNA-seq to detect embryonic mice and stem cells will help improve the in vitro differentiation protocol and quality control of cell therapy,as well as evaluate the overall cell quality and developmental stage of dopaminergic neurons derived from stem cells.
2.Production of GTKO pigs and kidney xenotransplantation from pigs to rhesus macaques
Yan WANG ; Yue CHANG ; Chang YANG ; Taiyun WEI ; Xiaoying HUO ; Bowei CHEN ; Jiaoxiang WANG ; Heng ZHAO ; Jianxiong GUO ; Hongfang ZHAO ; Xiong ZHANG ; Feiyan ZHU ; Wenmin CHENG ; Hongye ZHAO ; Kaixiang XU ; Ameen Jamal MUHAMMAD ; Zhendi WANG ; Hongjiang WEI
Organ Transplantation 2025;16(4):526-537
Objective To explore the construction of α-1,3-galactosyltransferase (GGTA1) gene-knockout (GTKO) Diannan miniature pigs and the kidney xenotransplantation from pigs to rhesus macaques, and to assess the effectiveness of GTKO pigs. Methods The GTKO Diannan miniature pigs were constructed using the CRISPR/Cas9 gene-editing system and somatic cell cloning technology. The phenotype of GTKO pigs was verified through polymerase chain reaction, Sanger sequencing and immunofluorescence staining. Flow cytometry was used to detect antigen-antibody (IgM) binding and complement-dependent cytotoxicity. Kidney xenotransplantation was performed from GTKO pigs to rhesus macaques. The humoral immunity, cellular immunity, coagulation and physiological indicators of the recipient monkeys were monitored. The function and pathological changes of the transplanted kidneys were analyzed using ultrasonography, hematoxylin-eosin staining, immunohistochemical staining and immunofluorescence staining. Results Single-guide RNA (sgRNA) targeting exon 4 of the GGTA1 gene in Diannan miniature pigs was designed. The pGL3-GGTA1-sgRNA1-GFP vector was transfected into fetal fibroblasts of Diannan miniature pigs. After puromycin selection, two cell clones, C59# and C89#, were identified as GGTA1 gene-knockout clones. These clones were expanded to form cell lines, which were used as donor cells for somatic cell nuclear transfer. The reconstructed embryos were transferred into the oviducts of trihybrid surrogate sows, resulting in 13 fetal pigs. Among them, fetuses F04 and F11 exhibited biallelic mutations in the GGTA1 gene, and F04 had a normal karyotype. Using this GTKO fetal pig for recloning and transferring the reconstructed embryos into the oviducts of trihybrid surrogate sows, seven surviving piglets were obtained, all of which did not express α-Gal epitope. The binding of IgM from the serum of rhesus monkey 20# to GTKO pig PBMC was reduced, and the survival rate of GTKO pig PBMC in the complement-dependent cytotoxicity assay was higher than that of wild-type pig. GTKO pig kidneys were harvested and perfused until completely white. After the left kidney of the recipient monkey was removed, the pig kidney was heterotopically transplanted. Following vascular anastomosis and blood flow restoration, the pig kidney rapidly turned pink without hyperacute rejection (HAR). Urine appeared in the ureter 6 minutes later, indicating successful kidney transplantation. The right kidney of the recipient was then removed. Seven days after transplantation, the transplanted kidney had good blood flow, the recipient monkey's serum creatinine level was stable, and serum potassium and cystatin C levels were effectively controlled, although they increased 10 days after transplantation. Seven days after transplantation, the levels of white blood cells, lymphocytes, monocytes and eosinophils in the recipient monkey increased, while platelet count and fibrinogen levels decreased. The activated partial thromboplastin time, thrombin time and prothrombin time remained relatively stable but later showed an upward trend. The recipient monkey survived for 10 days. At autopsy, the transplanted kidney was found to be congested, swollen and necrotic, with a small amount of IgG deposition in the renal tissue, and a large amount of IgM, complement C3c and C4d deposition, as well as CD68+ macrophage infiltration. Conclusions The kidneys of GTKO Diannan miniature pigs may maintain normal renal function for a certain period in rhesus macaques and effectively overcome HAR, confirming the effectiveness of GTKO pigs for xenotransplantation.
3.Variation of 137Cs activity concentration in aerosol in Beijing
Huan WANG ; Qinghua MENG ; Yun LOU ; Bin BAI ; Weijie ZHU ; Hongfang WANG ; Yuxia KONG ; Zechen FENG ; Shuguang ZHAI ; Jun YU ; Yaru SUN ; Yongzhong MA
Journal of Environmental and Occupational Medicine 2024;41(9):1038-1042
Background 137Cs in atmospheric aerosol is the product of past nuclear weapon tests and nuclear accidents. When 137Cs is released into the atmosphere, it will deposit in dry land and marine environment, causing pollution of soil surface, water, agricultural products, and animal byproducts, and affecting public health. Objective To identify the variation pattern of 137Cs activity concentration in aerosol and its correlation with dust concentration in Beijing area from 2017 to 2020. Methods A total of 958 aerosol samples were collected from November 1, 2017 to June 30, 2020 in Beijing with a high volume air sampler at a sampling flow rate about 600 m3·h−1 and a collection time for each sample about 24 h. The activity concentration of 137Cs in the aerosol samples was determined with a low-background high-purity germanium γ spectrometer. The dust concentration was calculated using the difference in the mass of the aerosol filter before and after sampling. The detection rate of 137Cs and dust concentration in different seasons were compared. Spearman rank correlation test was used to analyze the correlation between 137Cs activity concentration and dust concentration. Results From 2017 to 2020, the 137Cs activity concentrations of 33 from 958 aerosol samples in Beijing were above the minimum detectable activityconcentration, the overall detection rate of 137Cs was 3.4%, and the activity concentration ranged from 1.86 to 45.53 μBq·m−3, with a median value of 4.85 μBq·m−3. The detection rate of 137Cs was highest in spring, followed by autumn, and lowest in winter and summer (8.4%, 3.0%, 1.1%, and 0.5%, respectively). The dust concentration ranged from 0.03 to 1.55 mg·m−3, with an average value of 0.18 mg·m−3. There was a statistically significant difference in the dust concentrations in spring, summer, autumn, and winter (F=45.51, P<0.05), and the highest value was 0.24 mg·m−3 in spring (P<0.05). The 137Cs activity concentration was positively correlated with the dust concentration (P<0.05). Conclusion The 137Cs activity concentration in aerosol in Beijing from 2017 to 2020 fluctuates within the range of background level, and its activity concentration is highest in spring, followed autumn, and lowest in summer and winter.
4.Epidemiological investigation of a brucellosis outbreak transmitted through a lamb slaughtering site
ZHANG Hongfang ; WANG Guohua ; LIU Jian ; QIAN Hua ; TANG Tao
Journal of Preventive Medicine 2024;36(10):887-888,892
Abstract
On August 11, 2022, Tongxiang Center for Disease Control detected a case of brucellosis, and the case was not engaged in related work. Case finding and risk factor investigation were immediately conducted to trace the source of infection. It was revealed that the case sold aquatic products at a farmer's market and frequently picked up goods at a seafood warehouse adjacent to a lamb slaughtering site. There was a potential risk of infection due to indirect contact with slaughtered lambs or contaminants. Serological tests were conducted on 9 employees of the slaughtering site and 48 residents nearby, and the brucellosis cases diagnosed in hospitals in the same area were searched. A total of 11 brucellosis cases were identified, including 9 confirmed cases and 2 asymptomatic infections. There were 2 cases of slaughtering workers and 9 cases of non-occupational individuals from the surrounding area of the slaughtering site. Brucella melitensis biovar 3 were isolated from a slaughtering worker and a non-occupational individual. The slaughtered lambs primarily came from northern regions such as Inner Mongolia and Heilongjiang. It was concluded that it was a cluster caused by Brucella melitensis biovar 3 and spread through direct or indirect contact with imported infected lambs or contaminated environments from a lamb slaughtering site. It is suggested to strengthen the quarantine of imported sheep, legally shut down non-compliant lamb slaughtering sites, implement designated slaughtering and enhance occupational protection.
5.Preliminary Study on Construction Method of Type 1 Diabetes Model in Banna Miniature Pig
Kai LIU ; Yuqi HU ; Yatian GENG ; Wenjie CHENG ; Jing WANG ; Taiyun WEI ; Hongfang ZHAO ; Jiayu LI ; Deling JIAO ; Hongye ZHAO ; Hongjiang WEI
Laboratory Animal and Comparative Medicine 2024;44(4):384-392
Objective To construct a Type 1 diabetes model in miniature pigs and explore postoperative care strategies for effectively prolonging the survival time of the model pigs.Methods Seven Banna miniature pigs were selected for pancreatectomy.Glucose,vitamins,and antibiotics were administered for 3-5 days after surgery to aid recovery.Blood glucose and urine glucose levels were measured twice a day in the morning and evening to adjust insulin supplementation accordingly.The model pigs were observed daily and records were kept,including orexis,psychosis,weakness,skin ulcer,and feces and urine.Body weight was measured weekly until the death of the model animals.Based on the model pigs'condition,glucose injection and Ringer's lactate solution were administered to supplement nutrition and correct electrolyte imbalances.Results All seven Banna miniature pigs showed typical symptoms of diabetes:random blood glucose levels higher than 11.1 mmol/L after pancreatectomy,far exceeding the average blood glucose level of 6.0 mmol/L in normal pigs;positive urine glucose;and progressive weight loss.These features indicated the successful construction of Type 1 diabetes model.Additionally,Type 1 diabetic pigs that survived more than 8 weeks showed progressive hair loss and skin ulceration.Euthanasia was performed on model pigs when they were unable to stand or even eat independently,and pathological examination and HE staining were conducted on tissues collected from affected organs such as the liver,kidneys,and skin.Pathological sections revealed liver congestion,massive glycogen accumulation,ballooning degeneration of hepatocytes,and progressive liver fibrosis,along with glomerular congestion,vacuolar degeneration in renal tubular epithelial cells,proteinuria,dermal congestion,thinning of vascular walls,and varying degrees of parakeratosis and dyskeratosis in the liver,kidneys,and skin tissues due to prolonged hyperglycemia.The average survival time of the constructed Banna miniature pig diabetes model was 44 d,with a maximum survival time of 121 d.Conclusion Type 1 diabetes model can be constructed successfully in Banna miniature pigs through pancreatectomy.With meticulous postoperative care,a long-term Type 1 diabetes model with significant complications can be achieved,providing a stable large-animal model for Type 1 diabetes treatment strategies.
6.Application value of modified multivisceral transplantation in chronic intestinal pseudo-obs-truction secondary to autoimmune leiomyositis
Changzhen ZHU ; Yuanxin LI ; Zhidong ZHU ; Feng WANG ; Qian ZHANG ; Tianlei XU ; Huan LI ; Hongfang YIN
Chinese Journal of Digestive Surgery 2024;23(9):1178-1187
Objective:To investigate the application value of modified multivisceral trans-plantation (MMT) in chronic intestinal pseudo-obstruction (CIPO) secondary to autoimmune enteril leiomyositis (AEL).Methods:The retrospective and descriptive study was conducted. The clinico-pathological data of a recipient who was admitted to Beijing Tsinghua Changgung Hospital Affiliated to Tsinghua University on February 2022 and underwent MTT for CIPO secondary to AEL were collected. The recipient was a male, aged 29 years old. Results of preoperative histopathological examination showed that there were muscle plexus and ganglion cells in the rectum, sigmoid colon, ascending colon, intrinsic muscle layer of ileum, and a small amount of submucosal layer. There was also a small amount of chronic inflammatory cell infiltration in the muscle, indicating a high possi-bility of diagnosis of neurogenic CIPO.Results:(1) Surgical situations. The operation time was 14 hours and 30 minutes, and the cold ischemia time was 9 hours and 30 minutes. The intra-operative blood product dosage included 14 U of red blood cells, 1 400 mL of fresh frozen plasma, and two therapeutic doses of platelets. (2) Postoperative histopathological examination. Results of postoperative histopathological examination showed chronic inflammation and local erosion of the small intestine and duodenal mucosa, with scattered disappearance of the focal mucosal muscle layer; There is a large infiltration of CD3 + and CD8 + lymphocytes in the lamina propria, especially in the muscularis propria. In severe lesions, there is infiltration of ribbon lymphocytes in the subserosal and muscular layers; Muscle fiber degeneration, reduction, and fibrosis. Deposition of pigment granules in the cytoplasm of smooth muscle cells; No abnormalities were found in the intermuscular, submu-cosal ganglia, and Cajal cells; Fibrosis of the serosal layer with local cellulose exudation; Chronic inflammation of the colonic mucosa, scattered and focal lymphocyte infiltration in the local muscle layer, and myositis related changes. Pathological diagnosis was secondary CIPO induced by AEL. (3) Postoperative immune rejection, recurrence and treatment. Results of colonoscopy and histopatholo-gical examination at postoperative 8 days showed acute cellular rejection. The cell count of reci-pient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes were 27.00×10 3, 373.00×10 3, 179.00×10 3 and 142.00×10 3 cell/mL, respectively. Anti-immune rejection treatment was performed using tacrolimus, rabbit anti-human thymocyte immunoglobulin, methylprednisolone mycophenolate mofetil, and monoclonal antibodies against basil. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes at postoperative 57 days were 0.72×10 3, 239.59×10 3, 89.28×10 3 and 91.53×10 3 cell/mL, respectively. Results of colonoscopy and histopathological examination at postoperative 79 days showed the recurrence of AEL. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lymphocytes, and CD8 + lymphocytes were 0.32×10 3, 264.92×10 3, 46.95×10 3 and 169.54×10 3 cell/mL, respectively. The tacrolimus and methylprednisolone were used for treatment. Results of colonoscopy and histopathological examina-tion at postoperative 89 days showed AEL recurrence without remission. The cell count of recipient′s B lymphocytes, CD3 + lymphocytes, CD4 + lympho-cytes, and CD8 + lymphocytes were 0.28×10 3, 187.00×10 3, 55.52×10 3 and 92.45×10 3 cell/mL, respec-tively. The tacrolimus and methylprednisolone were used for treatment. Results of colonoscopy and histopathological examination at postoperative 92 days showed the intestinal mucosa had returned to a normal state. (4) Postoperative oral feeding time and time to get rid of parenteral nutrition. The recipient began oral feeding at postoperative 28 days and eliminated parenteral nutrition at postoperative 35 days. (5) Follow-up. The recipient was discharged 114 days after surgery and as of the follow-up deadline, the graft function was good. The recipient maintained a low-fat, high sugar, and high protein diet, completely consumed orally, with a body mass index of 22 kg/m 2, and has returned to normal work. Conclusion:MMT can be used for the treatment of CIPO secondary to AEL.
7.Predicting the risk of local tumor progression after radiofrequency ablation of hepatocellular carcinoma
Hongfang WANG ; Guanhua YANG ; Minglei WANG ; Yu BAI ; Yong CHEN
Journal of Practical Radiology 2024;40(11):1875-1879
Objective To investigate the risk factors for identifying local tumor progression(LTP)in patients with hepatocellular carcinoma(HCC)after radiofrequency ablation(RFA)and to establish a predictive model.Methods The clinical data of 122 HCC patients treated by RFA were analyzed retrospectively,and then the patients were divided into positive and negative LTP groups according to that whether LTP occurred within 12 months after RFA.The risk factors of LTP were determined using univariate and multivari-ate analysis,and the predictive model was constructed based on these factors and the internal validation was conducted.Results The results of this study showed that multiple number,diameter>2 cm,rough margin,and adjacent to large blood vessels of the tumor could be independent predictors of LTP,which were further incorporated into constructing the predictive model.Internal validation results showed that the area under the curve(AUC)of receiver operating characteristic(ROC)curve was 0.815[95%confidence interval(CI)0.735-0.895],indicating the model with high differentiation ability.The calibration curve was drawn and the Hosmer-Lemeshow goodness-fit test showed that the model had good stability(P>0.05).The decision curve suggested that the model had good clinical application value.Conclusion The independent risk factors of LTP of HCC after RFA are multiple number,diameter>2 cm,rough margin,and adjacent to large blood vessels of the tumor.When the predictive model is integrated with the above factors,it can poten-tially predict the risk of local tumor and may offer useful guidance for individual treatment and follow-up.
8.Prone position-cardiopulmonary resuscitation in adults: a scoping review
Xuhong LAN ; Longfei GUO ; Hongfang ZHOU ; Hengyang WANG ; Qian WANG ; Donghui JIA ; Wenjuan YUAN ; Yuchen WU ; Zhigang ZHANG ; Caili PENG
Chinese Critical Care Medicine 2024;36(10):1049-1055
Objective:To comprehensively search the relevant literature on prone position-cardiopulmonary resuscitation (PP-CPR) in adults at home and abroad, analyze the content, summarize the evidence, and provide reference for clinical health care professionals.Methods:Systematic search of CNKI, China Biomedical Literature Service System (SinoMed), Wanfang Data, VIP database, PubMed, Embase, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochran Library, Web of Science, Scopus literature database and other Chinese and English databases was conducted. The search period was from inception to June 15 in 2024. The contents of PP-CPR from randomized controlled trial (RCT), non-RCT (prospective or retrospective), cohort studies and case reports were extracted and systematically analyzed. The search results were standardized by the method of scoping review.Results:A total of 523 articles were obtained through preliminary search, and 14 references and gray literature were retrieved, totaling 537 articles. After strict screening by two researchers, a total of 26 literatures were included, 3 were non-RCT and 23 were case reports, involving 12 countries, including 3 in Chinese, 19 in English, 2 in French, 1 in German, and 1 in Korean. Three non-RCT demonstrated that compared with standard cardiopulmonary resuscitation (CPR), PP-CPR could produce higher pressure, and provide good respiratory and circulatory support. A total of 25 adult patients were included in the 23 case reports, of which 17 reported total recovery time and 13 reported PP-CPR time ≤ 5 minutes, all of which recovered spontaneous circulation, indicating the effectiveness of PP-CPR technology. In terms of final outcome, 4 patients (16.0%) died and 21 patients (84.0%) survived, indicating that PP-CPR technology could provide timely blood circulation and improve clinical outcomes for prone cardiac arrest patients. Among the 11 patients who reported complications after resuscitation, no neurological damage was found in the short-term outcomes, indicating that PP-CPR technology had a certain level of safety.Conclusions:PP-CPR can provide timely blood circulation for patients with cardiac arrest who are unable to lie supine quickly, and win "golden time" for defibrillation and further treatment. In clinical practice, medical staff need to evaluate the emergency environment, the number of rescuers and the specific condition of the patient, and implement first aid as soon as possible, so as to reduce the time of no blood flow in the vital organs of patients with cardiac arrest in prone position, and improve the clinical prognosis.
9.Metacognition in relation to quality of life in patients with ovarian cancer: mediating role of fear of disease progression
Hongfang SUN ; Ling CHEN ; Jing ZHANG ; Yan WANG ; Hongshuang LIU
Sichuan Mental Health 2023;36(6):532-537
BackgroundQuality of life, as a major criterion for judging the clinical outcome of ovarian cancer patients, can be affected by adverse psychological symptoms of patients. Meanwhile, fear of disease progression, as a frequent psychological symptom among cancer survivors, is significantly influenced by metacognition, while there is a paucity of research into the specific correlation among the three in patients with ovarian cancer. ObjectiveTo explore the correlation among fear of disease progression, metacognition and quality of life in patients with ovarian cancer, and to test the role of fear of disease progression in the relationship between metacognition and quality of life, so as to provide references for improving the quality of life in patients with ovarian cancer. MethodsA total of 135 patients with ovarian cancer hospitalized in Cangzhou People's Hospital of Hebei Province from January 2019 to December 2022 were selected. All subjects were requested to complete the Functional Assessment of Cancer Therapy-Ovarian Cancer (FACT-O), Fear of Progression Questionnaire-Short Form (FoP-Q-SF) and Metacognition Questionnaire (MCQ) to assess their quality of life, fear of disease progression and metacognitive level. Pearson correlation analysis was adopted to examine the correlation among the above scales. Process v3.5 macro program was utilized to determine the mediating effect of fear of disease progression on the relationship between metacognition and quality of life, and nonparametric Bootstrap with bias-correction was used to test the mediating effect. ResultsA total of 122 patients (90.37%) with ovarian cancer completed the effective questionnaire survey. Patients scored (90.52±17.13) on FACT-O, (68.52±16.31) on MCQ, and (37.72±8.91) on FoP-Q-SF. Pearson correlation analysis denoted that FoP-Q-SF score was negatively correlated with FACT-O score (r=-0.412, P<0.05) and positively correlated with MCQ score (r=0.241, P<0.05), and MCQ score was negatively correlated with FACT-O score (r=-0.453, P<0.05). Analysis demonstrated that the total effect of metacognition on quality of life was -0.298 (95% CI: -0.402~-0.186). The direct effect of metacognition on quality of life was -0.219 (95% CI: -0.504~-0.277), accounting for 73.49% of the total effect, and the indirect effect of metacognition on quality of life via fear of disease progression was -0.079 (95% CI: -0.162~-0.037), accounting for 26.51% of the total effect. ConclusionQuality of life is reduced in patients with ovarian cancer, and fear of disease progression plays a partial mediating role in the relationship between metacognition and quality of life.
10.Investigation on present state of radiation protection of a 60Co irradiation facility
Hongfang WANG ; Zechen FENG ; Huan WANG ; Bin BAI ; Shuguang ZHAI ; Yongzhong MA
Chinese Journal of Radiological Medicine and Protection 2023;43(3):204-208
Objective:To explore the present state of radiation protection in an operational large-sized irradiation facility and the distribution of incurred radiation doses in the controlled area under abnormal conditions, and to analyze the acompanied radiation risk.Methods:With an irradiation facility in operation as the research object, the radiation doses were measured using AT1121 X and gamma dose rate meters for the soruce both in working and storage. Thermoluminescent dosimeters (TLDs) were used to measure the dose distribution in an irradiation field under abnormal conditions. The radiation safety features were checked against the several relevant national standards, with the radiation risks evaluated.Results:The radiation dose rates were in the range of 0.09-0.11 μSv/h, lower than the environmental background level whether in storage or working. Under abnormal working conditions, the radiation dose values from high to low were 1.0-101.3 Sv, 32.7-514.0 mSv and 8.7-183.2 μSv in the irradiation field, respectively. At the outside maze, the doses were close to the background level.Conclusions:The protection features of the irradiation facility meet the requirements of the relevant national standards. Under abnormal conditions, radiation could cause serious damages to the persons staying in the irradiation field. These persons were suggested to access to maze as soon as possible to reduce the exposure time, and activate the emergency protection equipments to deescalate the 60Co source onto the well.


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