Cellular recovery kinetics for postirradiation treatments.
Cellular recovery kinetics for postirradiation treatments.
复制标题
辐射后治疗的细胞恢复动力学。
DOI：
10.1080/09553009214552191
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发表时间：
1992
影响因子：
2.6
通讯作者：
Ostashevsky,JY
中科院分区：
文献类型：
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作者：
Ostashevsky,JY
在先前发展的DSB模型(Ostashevsky 1989)的框架下，分析了延迟电镀、ARAA、高渗盐水(HS)及其组合的辐射后细胞恢复动力学。考虑了两种可能的DNA双链断裂(DSB)修复动力学：合作和非合作，其中限速步骤与DNA分子有关，而限速步骤与DSB相关。对平台期V79细胞进行了以下估计：(1)HS导致DSB修复的暂时性阻断。对于DSB修复阻断持续时间的估计，10min处理约为0.6h，20min处理约为1.2h。(2)HS产生额外的DNA片段。0.37mNaC l处理所计算的这些片段的数目与0.5mNaC l处理的合作性DSB修复的估计数一致，但与非合作性DSB修复的估计数不同。(3)限制DNA片段形成的时间常数估计为10-20min。在200-400µMaraa存在的情况下，此过程的速率应降低2-5倍。(4)ARAA恢复动力学的时间常数与DSB修复的时间常数一致，与实验数据一致。(5)对于延迟电镀修复，协同DSB修复的动力学曲线与实验数据吻合较好，而非合作DSB修复的动力学曲线与实验数据吻合较好。
Postirradiation cellular recovery kinetics for delayed plating, araA, hypertonic saline (HS) treatments and their combinations, were analysed in the framework of the previously developed dsb model (Ostashevsky 1989). Two possible types of DNA double-strand break (dsb) repair kinetics were considered: cooperative, where the rate-limiting step is related to a DNA molecule, and non-cooperative, where the rate-limiting step is related to a dsb. The following estimates were made for plateau-phase V79 cells: (1) HS induces a temporary block of dsb repair. The estimates for the dsb repair block duration are about 0·6 h for a 10-min treatment and about 1·2 h for a 20-min treatment. (2) HS creates additional DNA fragments. The number of these fragments calculated for 0·37mNaCl treatment, in a way independent of the type of dsb repair, was consistent with the number estimated for 0·5mNaCl treatment for cooperative dsb repair, but not for noncooperative dsb repair. (3) The estimated time constant for the process restricting the formation of DNA fragments was 10–20 min. In the presence of 200–400 µmaraA, the rate of this process should decrease 2–5-fold. (4) The time constant for the araA recovery kinetics coincides with that for dsb repair, in agreement with experimental data. (5) For delayed plating recovery the kinetics curve calculated for cooperative dsb repair fits well experimental data, in contrast to the curve calculated for non-cooperative dsb repair.