Monte Carlo track structure applications in microdosimetry and radiation response

在放射治疗中，电离辐射用于对DNA造成不可修复的损伤并抑制癌细胞的细胞周期。叠加在DNA模型上的粒子轨迹表明，损伤是以簇的形式发生的。这些成簇的DNA损伤是电离辐射诱导的标志性DNA损伤。对辐射的生物反应用相对生物有效性（RBE）来量化，RBE定义为给定生物学终点的参考辐射吸收剂量与测试辐射吸收剂量之间的比率。低能量近距离放射治疗源、质子和离子束与高RBE值相关。初始DNA损伤的许多模拟表明，在代表DNA片段的体积中赋予的电离或能量的频率分布对于考虑辐射质量和模拟电离辐射产生的生物损伤是有用的。

In radiation therapy ionizing radiation is used to cause irreparable damage to the DNA and inhibit cell cycling of the cancer cells. Particle tracks superimposed on models of DNA indicate that damage occurs in clusters. These clustered DNA damages are the signature DNA lesion induced by ionizing radiation. The biological response to radiation is quantified in terms of the relative biological effectiveness (RBE), defined as the ratio between the absorbed dose of a reference radiation and that of a test radiation for a given biological endpoint. Low energy brachytherapy sources, proton and ion beams are associated with high RBE values. Numerous simulations of initial DNA damage suggest that the frequency distributions for ionisation or energy imparted in volumes representative of DNA segments are useful for considering radiation quality and for modelling biological damage produced by ionising radiation.