Radiation quality and mechanisms of radiation risk

这项NSERC发现续期拨款将继续支持现有的主要NSERC资助（发现和IRC）研究项目，重点是了解低剂量辐射与生物系统的相互作用。我们的研究开发了敏感的生物模型系统，以研究受低剂量辐射照射影响的广泛生物过程。我们已经设计、建造并正在调试一个单离子生物微束（也称为微探针），用于研究极低辐射剂量对细胞和活组织的物理相互作用和微剂量学效应。这种微型探针可以将粒子加速器产生的单个或多个带电粒子（质子或阿尔法粒子）“射”到活细胞内的精确位置。带电粒子具有很高的线性能量传递（LET），当它们瞄准特定的细胞和细胞内的目标时，可以研究DNA损伤和修复的基本过程，癌症和抗癌过程，以及受损细胞和非受损细胞之间的相互作用/通信。了解这些生物过程是很重要的，因为带电粒子是自然产生的（也是人造的），所有生物都受到它们的影响。麦克马斯特大学生物微束的发展将是本提案的一个重点，其具体目的是了解低剂量和低剂量率高LET辐射引起的基因组效应的机制。这项研究的预期结果将是更好地了解辐射剂量学和受不同类型的辐射质量和照射水平影响的细胞机制。利用微光束进行的研究将为下一代辐射探测和测量以及辐射生物学专家提供教育、培训和经验。这项研究将有助于提供有用的证据，可用于改善辐射防护措施，并支持监管机构和政府做出明智的决策。

This NSERC Discovery renewal grant will continue to support a major existing NSERC funded (Discovery and IRC) research program focused on understanding low dose radiation interaction with biological systems. Our research has developed sensitive biological model systems to study a wide range of biological processes influenced by low dose radiation exposure. We have designed, constructed, and are commissioning a single-ion biological microbeam (also called a microprobe) for studies of the physical interactions and microdosimetric effects of very low radiation doses on cells and living tissue. The microprobe can "shoot" a single or multiple charged particles (protons or alphas) generated by a particle accelerator into a precise location within a living cell. Charged particles have high linear energy transfer (LET) and when aimed at specific cells and targets within cells, allow the study of fundamental processes of DNA damage and repair, cancer and anti-cancer processes, as well as interactions/communications between damaged and non-damaged cells. Understanding these biological processes is important because charged particles occur naturally (and are man-made) and all living organisms are impacted by them. The development of the McMaster University biological microbeam will be one focus of this proposal with the specific aim of understanding the mechanisms responsible for genomic effects caused by low dose and low dose rate high LET radiation. The anticipated outcomes for this research will be a better understanding of radiation dosimetry and the cellular mechanisms influenced by different types of radiation quality and exposure levels. The research performed with the microbeam will provide education, training and experience for the next generation of experts in radiation detection and measurement, and radiation biology. This research will help provide useful evidence that can be used to improve radiation protection practices and support informed decision making by regulators and government.