Antonelli F, Belli M, Campa A, Chatterjee A, Dini V, Esposito G, Rydberg B, Simone G, Tabocchini M A
Istituto Superiore di Sanità, Rome, Italy.
Adv Space Res. 2004;34(6):1353-7. doi: 10.1016/j.asr.2003.11.020.
Outside the magnetic field of the Earth, high energy heavy ions constitute a relevant part of the biologically significant dose to astronauts during the very long travels through space. The typical pattern of energy deposition in the matter by heavy ions on the microscopic scale is believed to produce spatially correlated damage in the DNA which is critical for radiobiological effects. We have investigated the influence of a lucite shielding on the initial production of very small DNA fragments in human fibroblasts irradiated with 1 GeV/u iron (Fe) ions. We also used gamma rays as reference radiation. Our results show: (1) a lower effect per incident ion when the shielding is used; (2) an higher DNA Double Strand Breaks (DSB) induction by Fe ions than by gamma rays in the size range 1-23 kbp; (3) a non-random DNA DSB induction by Fe ions.
在地球磁场之外，在宇航员漫长的太空旅行中，高能重离子构成了生物显著剂量的一个相关部分。据信，重离子在微观尺度上在物质中的典型能量沉积模式会在DNA中产生空间相关的损伤，这对放射生物学效应至关重要。我们研究了有机玻璃屏蔽对用1 GeV/u铁（Fe）离子辐照的人类成纤维细胞中非常小的DNA片段初始产生的影响。我们还使用伽马射线作为参考辐射。我们的结果表明：（1）使用屏蔽时每个入射离子的效应较低；（2）在1 - 23 kbp大小范围内，Fe离子诱导的DNA双链断裂（DSB）比伽马射线更高；（3）Fe离子诱导的DNA DSB是非随机的。
