Kruszewski M, Wojewódzka M, Iwanenko T, Collins A R, Szumiel I
Department of Radiobiology and Health Protection, Institute of Nuclear Chemistry and Technology, Warsaw, Poland.
Mutat Res. 1998 Aug 7;416(1-2):37-57. doi: 10.1016/s1383-5718(98)00074-6.
In the preceding paper [M. Wojewodzka, M. Kruszewski, T. Iwanenko, A.R. Collins, I. Szumiel, Application of the comet assay for monitoring DNA damage in workers exposed to chronic low dose irradiation. I. Strand breakage., Mutat. Res. 416 (1998) 21-35], we reported the results of DNA damage examination carried out for a group of people (49 individuals) professionally at risk of exposure to low doses of ionizing radiation as measured by the alkaline comet assay. Here, we used the method in combination with oxidative base damage-specific endonucleases to estimate base damage in the same individuals. These were endonuclease III (endoIII) and formamidopyrimidine glycosylase (FPG). In contrast to the previous investigations, we found no statistically significant difference in base damage between the control and hazard groups. Interestingly, the hazard group exhibited lower level of enzyme-sensitive sites than the control; however, this different was not significant. No correlation of base damage with age was found, similarly as in the case of DNA damage measured by the alkaline comet assay. Interindividual variability of base damage precluded exposure estimation for single individuals, since several members of the control group exhibited high comet parameters.
在前一篇论文[M. Wojewodzka, M. Kruszewski, T. Iwanenko, A.R. Collins, I. Szumiel, 应用彗星试验监测长期低剂量辐射暴露工人的DNA损伤。I. 链断裂，《突变研究》416 (1998) 21 - 35]中，我们报告了通过碱性彗星试验对一组职业上有低剂量电离辐射暴露风险的人群（49人）进行DNA损伤检测的结果。在此，我们将该方法与氧化碱基损伤特异性核酸内切酶相结合，以评估同一人群中的碱基损伤。这些酶是核酸内切酶III（endoIII）和甲酰胺嘧啶糖基化酶（FPG）。与先前的研究不同，我们发现对照组和危险组之间的碱基损伤没有统计学上的显著差异。有趣的是，危险组的酶敏感位点水平低于对照组；然而，这种差异并不显著。未发现碱基损伤与年龄之间存在相关性，这与通过碱性彗星试验测量的DNA损伤情况类似。由于对照组的几名成员表现出较高的彗星参数，碱基损伤的个体间变异性使得无法对单个个体进行暴露估计。
