Modelling of DNA damage induced by energetic electrons (100 eV to 100 keV)
Modelling of DNA damage induced by energetic electrons (100 eV to 100 keV)
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DOI：
10.1093/oxfordjournals.rpd.a006843
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发表时间：
2002-01-01
影响因子：
1
通讯作者：
Goodhead, DT
中科院分区：
文献类型：
--
作者：
Nikjoo, H;Bolton, CE;Goodhead, DT
建模和计算的光谱产生的初始DNA损伤的能量为100 eV至100 keV的电子。初始损伤谱分析。基于损伤的来源（直接能量沉积和与扩散OH自由基的反应）和复杂性。表明大多数相互作用不会对DNA造成损伤，并且确实发生的任何损伤最有可能是简单的单链断裂（SSB）。高能电子的复合损伤的分数低于由锁定能量电子和超软X射线引起的复合损伤的分数，但仍代表轮胎总双股断裂（DSB）的可观分数（20-30%）。链断裂的相对产率的依赖于假设的能量沉积阈值和（在羟基自由基产生单链断裂的概率）进行了研究。在所研究的电子能量范围内，直接损伤与间接损伤的比率没有显著变化，并且这些值完全在实验数据范围内。DNA中的直接能量沉积代表了较大比例的轮胎损伤，尽管从断裂的绝对产率和损伤的复杂性来看，来自羟基自由基的贡献也很大。
Modelling and calculations are presented for the spectrum of initial DNA damage produced by 100 eV to 100 keV energetic electrons. Analysis of the initial spectrum of damage. based upon the source (direct energy deposition and reactions with diffusing OH radicals) and complexity of damage. indicates that tire majority of tire interactions cause no damage to DNA and any damage that does occur is most likely to be a simple single strand break (SSB). The fraction of complex damage for energetic electrons is lower than that induced by lock energy electrons and ultrasoft X rays but still represents an appreciable fraction (20-30%) of tire total double strand breaks (DSBs). Relative yields of strand breaks are investigated for dependence on the assumed energy deposition threshold and (in the probability of the hydroxyl radicals to produce a single strand break. The ratio of direct to indirect damage does not change significantly across the electron energy range investigated and the values lie well within tire experimental data. The direct energy deposition in DNA represents a larger proportion of tire damage although the contribution from the hydroxyl radicals is also substantial, both in terms of the absolute yield of the breaks and the complexity of the damage.