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Objective To continue following up the cohort members in Jiangsu province who were the largest subgroup in Chinese medical X-ray workers cohort subgroups on radiation carcinogenesis and analysis the cancer risk of medical X-ray workers which might be induced by chronic low-dose ionizing radiation between 1997 and 2011.Methods A retrospective cohort study was utilized to accumulate data.Epicure was applied to compute cumulative person years (with module of Datab) and relative risk (including 95％ CI) of malignant tumor on exposed group(with module of AMFIT) while the factors such as sex and attained-age were adjusted in the cohort members.Results The 7 708 follow-up members included 3 668 medical X-ray workers.The cumulative person-year in the cohort members was 94 651.2 (1997-2011) and its lost rate was 5.79％.During the follow-up period,441 cases had became cancer patients.The relative risk of all cancers was 1.44 (95％ CI:1.18-1.75),so was the solid cancers.Significant elevated risks of cancer were found on lung (RR =1.95,95％ CI:1.30-2.92),esophagus (RR =3.04,95％ CI:1.20-7.70),lymphoma(RR =2.24,95％ CI:0.67-7.48),leukemia(RR =1.57,95 ％ CI:0.33-7.39),throat (RR =2.47) and thyroid (RR =2.80,95 ％ CI:0.24-32.26) among medical X-ray workers.However,The RR of malignant tumors might not be associated with occupational exposure to ionizing radiation if we considered the lost factors (RR =1.2,95％ CI:0.94-1.46)Conclusions The RR of malignant tumors such as the cancer on lung,esophagus,thyroid among the medical X-ray workers in Jiangsu province were enhanced which might be associated with occupational exposure to ionizing radiation.
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Objective To study the relationship between the risk of malignant tumor and occupational radiation factor among medical diagnostic X-ray workers in Jiangsu province.Methods The retrospective and prospective cohort studies were adopted to investigate the incidence of cancer.Eligible medical diagnostic X-ray workers from the department of radiology in hospitals were selected and assigned into exposure group,while other medical workers from the departments of Internal Medicine,Ear-NoseThroat (ENT) or Pediatrics who attended work at the same period in the same hospital but not engaged in radiation work were regarded as control group during 1950-2011 in Jiangsu province.We calculated the total person-year and analyzed the relative risk (RR) of malignant tumor using Poisson regression model.Results 7 703 participants (3 961 in exposed group and 3 742 in unexposed group) were recruited and followed up,with a total of 315 309 person years and the lost follow-up rate was 6.92％ (533/7 703).During the follow up period,a total of 819 tumor cases were identified (771 were malignant tumors).We found the significant relationship between the risk of malignant tumor and occupational radiation factor,and the RR of solid cancer and total malignant tumor were 1.31 (95％ CI:1.11-1.55) and 1.33 (95％ CI:1.13-1.57),respectively.In addition,the risk of lung cancer in medical diagnostic X-ray workers was significantly higher than that in control group (RR =1.45,95％ CI:1.00-2.09).Conclusions The incidence risk of lung cancer,solid caner and total malignant tumors in medical diagnostic X-ray workers was significantly higher than that in the control group,which might be associated with occupational exposure to ionizing radiation.
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Objective To investigate the expression and function of SH2 domain containing protein tyrosine phosphatase SHP 2 of thymocytes in ? ray irradiation induced leukemia in mice. Methods BALB/c mice were divided into canceration group, non canceration group, and control group. The expression, level of tyrosine phosphorylation, and enzyme catalytic activity of SHP 2 in thymocytes were detected by Western blotting, immunoprecipitation, and biochemical method. Results There was obvious correlation among the expression, level of tyrosine phosphorylation, and enzyme catalytic activity of SHP 2, which were significantly higher in the canceration group than those in the non canceration group and the control group ( P
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Objective To investigate alteration of SHP-2 mRNA and protein of bone marrow cells of leukemia mice after ?-ray exposure.Methods A total of 318 BALB/c mice were exposed to ~(60)Co ?-ray once a week for 4 weeks,and the total dose of ?-ray received by mice was 7.00 Gy.By pathological examination,39 mice developed thymic lymphoma,14 acute lymphoblastic leukemia,21 T-lymphoblast leukemia/lymphoma,1 spiroma,4 malignant yolk sac tumors.Exposed to ?-ray,the mice that developed leukemia or were free of canceration were used in our study(n=10 in each group),and another 10 mice free from irradiation served as control.SHP-2 mRNA and protein in femoral bone marrow cells were detected by real time fluorescence quantitative PCR(FQ-PCR) and Western blotting respectively.Results SHP-2 mRNA was(5.08?2.87) in leukemia mice,(4.59?2.36) in mice free of canceration and(3.54?1.02) in controls.SHP-2 protein was(0.956?0.125) in leukemia mice,(0.892?0.236) in mice free of canceration and(0.712?0.368) in controls.The enzyme catalytic activity of SHP-2 was(0.156?0.069),(0.118?0.065),(0.098?0.048).No significant difference in mRNA,protein or enzyme catalytic activity of SHP-2 was found in leukemia mice,mice free from canceration and control mice.Conclusion SHP-2 mRNA and protein was significantly increased in bone marrow cells of leukemia mice induced by ?-ray irradiation.
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Objective To investigate the alterations of SHP-2 mRNA of thymus cells of mice with ? ray-induced leukemia. Methods BALB/c mice were randomly divided into canceration group, non-canceration group, and control group. The gene mutation and content of SHP-2 mRNA in thymus cells were detected by PCR-SSCP, DNA sequencing, and real time fluorescence quantitative PCR (FQ-PCR). Results PCR-SSCP showed there was gene mutation within 700～1 096 bp of SHP-2 mRNA in thymus cells of mice in the canceration group, which was not supported by DNA sequencing. No significant difference in change of SHP-2 mRNA content was found in thymus cells in canceration, non-canceration, and control groups. Conclusion There is translational abnormality of SHP-2 mRNA in thymus cells of mice with ? ray-induced leukemia, which is presented as translational enhancement.
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Objective To investigate alteration of SHP-1 mRNA and protein of bone marrow cells of leukemia mice after ?-ray exposure.Methods A total of 318 BALB/c mice were exposed to ~(60)Co ?-ray once a week for 4 weeks,and the total dose of ?ray received by mice was 7.00 Gy.By pathological examination,39 mice developed thymic lymphoma,14 acute lymphocytic leukemia,21 T-lymphoblast leukemia/lymphoma,1 spiroma,4 malignant yolk sac tumor.Exposed to ?-ray,the mice that developed leukemia or were free of canceration were used in our study(n=10 in each group),and another 10 mice free from irradiation served as control.SHP-1 mRNA and protein in femoral bone marrow cells were detected by real-time fluorescence quantitative PCR(FQ-PCR) and Western blotting respectively.Results SHP-1 mRNA in leukemia mice was(5.26?2.14),significantly higher than that of mice free of canceration(3.68?1.27) and controls(2.95?1.09)(P