LETHAL AND POTENTIALLY LETHAL LESIONS INDUCED BY RADIATION - A UNIFIED REPAIR MODEL
LETHAL AND POTENTIALLY LETHAL LESIONS INDUCED BY RADIATION - A UNIFIED REPAIR MODEL
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DOI：
10.2307/3576798
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发表时间：
1986-05-01
影响因子：
3.4
通讯作者：
CURTIS, SB
中科院分区：
文献类型：
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作者：
CURTIS, SB
辐射作用的模型描述了几个主要的现有概念已被应用到细胞杀伤的统一。被称为致死和潜在致死（LPL）模型，它结合了病变相互作用、单轨迹引起的不可修复病变、线性病变固定、通过一级动力学进行的病变修复和二元误修复的想法。假设有两种不同类型的病变：不可修复（致命）和可修复（潜在致命）病变。他们正在初步确定与不同严重程度的DNA双链断裂。两个过程竞争消耗潜在的致命病变：正确的修复后的一级动力学，和错误修复后的二级动力学。也可能发生这些病变的固定。该模型目前仅适用于平台期（稳定期）细胞。所描述的放射生物学现象包括低剂量率、高LET和修复动力学的影响，如用修复抑制剂（例如高渗溶液和β-半乳糖）测量的。阿拉伯呋喃糖基腺嘌呤（β- araA）。该模型的一个结果是，亚致死性损伤的修复和潜在致死性损伤修复的缓慢部分是同一修复过程的两种表现。高渗治疗修复了一种全新的病变类型，通常可以正确修复。该模型的另一个结果是，存活曲线的初始斜率取决于照射后可用于修复的时间量。出现在几个线性二次配方的“剂量率因子”出现时，适当的低剂量和长修复时间的近似。
A model of radiation action is described which unifies several of the major existing concepts which have been applied to cell killing. Called the lethal and potentially lethal (LPL) model, it combines the ideas of lesion interaction, irreparable lesions caused by single tracks, linear lesion fixation, lesion repair via first-order kinetics, and binary misrepair. Two different kinds of lesions are hypothesized; irreparable (lethal) and repairable (potentially lethal) lesions. They are tentatively being identified with DNA double-strand breaks of different severity. Two processes compete for depletion of the potentially lethal lesions: correct repair following first-order kinetics, and misrepair following second-order kinetics. Fixation of these lesions can also occur. The model applies presently only to plateau (stationary)-phase cells. Radiobiological phenomena described include effects of low dose rate, high LET, and repair kinetics as measured with repair inhibitors such as hypertonic solution and .beta.-arabinofuranosyladenine (.beta.-araA). One consequence of the model is that repair of sublethal damage and the slow component of the repair of potentially lethal damage are two manifestations of the same repair process. Hypertonic treatment fixes a completely new class of lesions which normally repair correctly. Another consequence of the model is that the initial slope of the survival curve depends on the amount of time available for repair after irradiation. The "dose-rate factor" occurring in several linear-quadratic formulations is shown to emerge when appropriate low-dose and long-repair-time approximations are made.