Han Z B, Suzuki H, Suzuki F, Suzuki M, Furusawa Y, Kato T, Ikenaga M
Radiation Biology Center, Kyoto University, Japan.
J Radiat Res. 1998 Sep;39(3):193-201. doi: 10.1269/jrr.39.193.
Syrian hamster embryo cells were used to study the morphological transformation induced by accelerated heavy ions with different linear energy transfer (LET) ranging from 13 to 400 keV/micron. Exponentially growing cells were irradiated with 12C or 28Si ion beams generated by the Heavy Ion Medical Accelerator in Chiba (HIMAC), then inoculated to culture dishes. Morphologically altered colonies were scored as transformants. Over the LET range examined, the frequency of transformation induced by the heavy ions increased sharply at very low doses no greater than 5 cGy. The relative biological effectiveness (RBE) of the heavy ions relative to X-rays first increased with LET, reached a maximum value of about 7 at 100 keV/micron, then decreased with the further increase of LET. Our findings confirmed that high LET heavy ions are much more effective than X-rays for the induction of in vitro cell transformation.
叙利亚仓鼠胚胎细胞被用于研究不同线性能量传递（LET）范围从13至400keV/微米的加速重离子诱导的形态转化。将指数生长的细胞用千叶重离子医用加速器（HIMAC）产生的12C或28Si离子束辐照，然后接种到培养皿中。形态改变的集落被计为转化体。在所研究的LET范围内，重离子诱导的转化频率在不超过5cGy的非常低剂量下急剧增加。重离子相对于X射线的相对生物效能（RBE）首先随LET增加，在100keV/微米时达到约7的最大值，然后随LET的进一步增加而降低。我们的研究结果证实，高LET重离子在诱导体外细胞转化方面比X射线有效得多。
