C形臂X光机急性扫描诱导的生物效应研究

发布时间：2018-05-17 08:05

本文选题：C形臂X光机 + 氧化水平　；参考：《吉林大学》2015年硕士论文

【摘要】：目前，越来越多的C形臂X光机扫描被应用到骨科手术当中。虽然C形臂的和患者的健康产生了辐射损害。C形臂X光机的高频使用或者滥用导致医护人员和患者受到低剂量电离辐射照射，，累积的电离辐射可能导致受照人群（医护人员、患者和家属）发生随机性效应或确定性效应。此外，如何做好C形臂X光机在术中的辐射防护也是放射防护领域亟需解决和关注的问题。低剂量电离辐射诱导的效应主要包括损伤效应和有益效应，这两种生物效应存在巨大的争议。低剂量电离辐射诱导的有益效应包括兴奋性效应和适应性反应，而损伤效应则包括确定性效应和、随机性效应、旁效应、遗传效应和基因组不稳定性等。根据人群流行病学资料（日本原子弹爆炸幸存者数据），低剂量电离辐射诱导的损伤效应呈线性无阈模型，即辐射人群的癌症风险和与辐射剂量呈线性关系。科学家对线性无阈模型（LNT）的主要存在有两种截然不同的观点，一是线性无阈模型可能过高评估了辐射致癌风险，①100mSv-50mSv的辐射剂量不能诱发显著的生物效应；②辐射高本底的研究结果不能充分证实辐射损伤效应；③低剂量电离辐射能诱导有益效应；④电离辐射导致机体的DNA损伤，未必一定诱发癌症或者恶性肿瘤。二是线性无阈模型可能低估了电离辐射诱导的癌症风险，①电离辐射可以诱导旁效应；②存在辐射超敏感人群和基因组不稳定性。研究表明C形臂单次扫描或者少量多次扫描均在低剂量电离辐射的范围内，低剂量电离辐射诱导的生物效应尚且存在较大争议。所以研究C形臂X光机辐射诱导的生物效应不仅能丰富低剂量电离辐射理论，还能为辐射暴露人群提供相应的理论依据。目的研究C形臂X光机急性扫描对小鼠机体的生物效应方法将健康雄性BALB/c小鼠60只随即分为对照组、单次、四次、八次、十二次扫描组，每组12只。对照组小鼠不扫描，扫描组用C形臂X光机对小鼠进行全身扫描。用热释光剂量计测量每个实验组小鼠的吸收剂量率。在照射24小时后，制备并冻存细胞悬液、血清和小鼠的甲状腺组织。采用生物化学方法检测小鼠甲状腺组织中超氧化物歧化酶（SOD）和丙二醛（MDA）的水平；采用酶联免疫吸附试验(ELISA)检测血清中IL-4和IFN-γ的变化；流式细胞仪检测各照射组小鼠外周血淋巴和骨髓细胞的凋亡水平。结果 1.不同次数C形臂X光机扫描对小鼠甲状腺组织中MDA水平的影响甲状腺组织上清经试剂盒检测结果：和对照组相比，八次和十二次C形臂扫描显著增加了甲状腺中MDA的水平，并且MDA的水平在十二次C形臂扫描后达到顶峰，甲状腺组织中的MDA水平分别升高了2.39、3.49倍，差异具有统计学意义（F=8.31，P0.05）。 2.不同次数C形臂X光机扫描诱导的SOD水平变化甲状腺组织上清经试剂盒检测结果：和对照组相比，四次、八次和十二次C形臂扫描极大的降低了甲状腺中的SOD活性，SOD水平分别降低了19.23%、25.80%和27.95%（F=4.61, P0.05）。 3.不同次数C形臂扫描诱导的血清IFN-γ和IL-4水平血清经ELISA试剂盒检测结果：和对照组相比，血清IFN-γ和IL-4水平在四次、八次、十二次C形臂扫描后呈下降趋势，在十二次C形臂扫描后两者水平达到最低值，血清IFN-γ和IL-4水平在四次以上扫描后分别降低了14.71%和22.60%、22.99%和44.05%、31.70%和44.43%，差异有统计学意义（F=59.26，P0.05）; IFN-γ/IL-4比值在不同次数照射后均无显著变化，差异无统计学意义（F=12.47，P0.05）。 4.不同次数C形臂扫描诱导外周血淋巴细胞凋亡水平变化外周血淋巴细胞经流式细胞仪检测结果：和对照组相比，八次和十二次C形臂扫描增加了小鼠外周血淋巴细胞的凋亡水平，凋亡水分别增加了1.68、2.40倍，差异有统计学意义（F=23.56，P0.05）。 5.不同次数C形臂扫描诱导骨髓细胞的凋亡水平变化骨髓细胞经流式细胞仪检测结果：和对照组相比，十二次C形臂扫描增加了骨髓细胞的凋亡水平，凋亡水平增加了2.02倍，差异有统计学意义（F=19.31，P0.05）。结论 C形臂X光机多次扫描改变了机体的氧化水平和免疫学相关指标。另外，机体通过启动凋亡来为维持基因组稳定性。
[Abstract]:At present , more and more C - arm X - ray machine scanning has been applied to orthopedic surgery . Although C - arm and patient ' s health produce radiation damage , high - frequency use or abuse of C - arm X - ray machine can lead to random or deterministic effects of medical personnel and patients with low - dose ionizing radiation . Furthermore , how to do well the radiation protection of C - arm X - ray machine in operation is a problem that needs to be solved and cared for in radiation protection field .

The effects of low - dose ionizing radiation mainly include damage effect and beneficial effect , and the two biological effects are controversial . The beneficial effects induced by low - dose ionizing radiation include excitatory effect and adaptive response , but the damage effects include deterministic effects , random effects , side effects , genetic effects and genomic instability .
( 2 ) The results of high radiation background can not fully confirm the effect of radiation damage ;
( 3 ) Low - dose ionizing radiation can induce beneficial effects ;
( 4 ) Ionizing radiation leads to DNA damage in the organism , which may not necessarily induce cancer or malignancy . Second , the linear non - threshold model may underestimate the risk of ionizing radiation - induced cancer , and ( 1 ) ionizing radiation can induce side effects ;
The results show that the biological effects induced by low dose ionizing radiation are not only rich in low dose ionizing radiation , but also can provide theoretical basis for radiation exposure .

Purpose

Study on the Biological Effects of Acute Scan of C - arm X - ray Machine on Mice

method

Sixty healthy male BALB / c mice were randomly divided into two groups : control group , single , four , eight , and ten second scanning groups , 12 in each group . The control group mice did not scan , the scanning group scanned the mice with C - arm X - ray machine . After 24 hours of irradiation , the cells were prepared and frozen . The levels of superoxide dismutase ( SOD ) and malondialdehyde ( MDA ) in thyroid tissues of mice were detected by biochemical method .
ELISA was used to detect the changes of IL - 4 and IFN - 纬 in serum .
Flow cytometry was used to detect the level of apoptosis in peripheral blood lymphocytes and bone marrow cells of irradiated mice .

Results

Effect of different times of C - arm X - ray machine scanning on the level of MDA in thyroid tissue of mice

Results : Compared with the control group , the levels of MDA in the thyroid were significantly increased compared with the control group , and the level of MDA increased 2.39 , 3.49 times higher than that in the thyroid tissues ( F = 8.31 , P0.05 ) .

2 . Changes of SOD level induced by X - ray machine scanning at different times

Results : Compared with the control group , four , eight and ten C - arm scans significantly decreased the SOD activity in the thyroid , and the SOD level decreased by 19.23 % , 25.80 % and 27.95 % ( F = 4.61 , P0.05 ) .

3 . Serum IFN - 纬 and IL - 4 levels induced by C - arm scans at different times

The levels of IFN - 纬 and IL - 4 decreased by 14.71 % and 22.60 % , 22.99 % and 44.05 % , 31.70 % and 44.43 % , respectively .

4 . Changes of apoptosis in peripheral blood lymphocytes induced by C - arm scans of different times

Compared with the control group , eight and ten C - arm scans increased the level of apoptosis in peripheral blood lymphocytes of mice , and the apoptotic water increased by 1 . 68 and 2 . 40 times , respectively ( F = 23.56 , P0.05 ) .

5 . Changes of apoptosis in bone marrow cells induced by C - arm scans of different times

Compared with the control group , the apoptosis level of bone marrow cells increased by 2 . 02 times , and the difference was statistically significant ( F = 19.31 , P0.05 ) .

Conclusion

C - arm X - ray machine multiple scans have changed the body ' s oxidation level and immunological correlation index . In addition , the organism can maintain genome stability by initiating apoptosis .
【学位授予单位】：吉林大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：R687

【参考文献】