Hei T K, Komatsu K, Hall E J, Zaider M
Radiological Research Laboratory, College of Physicians and Surgeons, Columbia University, New York, NY 10032.
Carcinogenesis. 1988 May;9(5):747-50. doi: 10.1093/carcin/9.5.747.
Neoplastic transformation incidence and cytotoxicity were scored in the C3H/10T1/2 cell system following irradiation with charged particles of defined linear energy transfer (LET) produced at the Radiological Research Accelerator Facility of Columbia University. Cells cultured in monolayers, attached to thin Mylar sheets, were irradiated with accelerated protons, deuterons or helium-3 ions, and the results compared with X-rays. Defined LET values obtained by using the track segment mode, ranged from 10 to 120 keV/microns. For X-rays, and for the charged particles of lower LET, the dose-response curves for cell survival have a marked initial shoulder. With increasing LET, there is a progressive decrease in the size of the shoulder and for the highest LETs, survival curves approximate an exponential function of dose. The transformation incidence, likewise, showed a direct correlation to LET over the dose range examined. The efficiencies of transformation, however, appeared to approach a plateau between 80 and 120 keV/micron. Transformation data were analyzed using a linear-quadratic function of dose for the transformation probability. This latter quantity, when analyzed using microdosimetric consideration, suggests that the target volume for this end point is of the order of micrometer.
在哥伦比亚大学放射研究加速器设施产生的具有确定线能量转移（LET）的带电粒子辐照后，对C3H/10T1/2细胞系统中的肿瘤转化发生率和细胞毒性进行评分。将单层培养并附着在薄聚酯薄膜片上的细胞用加速质子、氘核或氦 - 3离子辐照，并将结果与X射线进行比较。使用径迹段模式获得的确定LET值范围为10至120 keV/微米。对于X射线以及较低LET的带电粒子，细胞存活的剂量 - 反应曲线有明显的初始肩部。随着LET增加，肩部尺寸逐渐减小，对于最高LET，存活曲线近似剂量的指数函数。在所检查的剂量范围内，转化发生率同样与LET呈直接相关。然而，转化效率似乎在80至120 keV/微米之间接近平稳状态。使用转化概率的剂量线性 - 二次函数分析转化数据。当使用微剂量学考虑因素进行分析时，后一个量表明该终点的靶体积约为微米量级。
