Inter-track and intra-track DNA fragment distributions in dependence of radiation quality, particle fluence and LET

Track detection on the cells exposed to high LET heavy-ions by CR-39 plastic and terminal deoxynucleotidyl transferase (TdT)

Background: The fatal effect of ionizing radiation on cells depends on Linear Energy Transfer (LET) level. The distribution of ionizing radiation is sparse and homogeneous for low LET radiations such as X or γ, but it is dense and concentrated for high LET radiation such as heavy-ions radiation. Material and Methods: Chinese hamster ovary cells (CHO-K1) were exposed to 4 Gy Fe-ion 2000 keV/...

Monte Carlo predictions of DNA fragment-size distributions for large sizes after HZE particle irradiation.

DSBs (double-strand breaks) produced by densely ionizing space radiation are not located randomly in the genome: recent data indicate DSB clustering along chromosomes. DSB clustering at large scales, from >100 Mbp down to approximately 2 kbp, is modeled using a Monte-Carlo algorithm. A random-walk model of chromatin is combined with a track model, that predicts the radial distribution of energy...

Proton beam dosimetry by CR-39 track-etched detector

Background: High and intermediate energy protons are not able to form a track in a solid state nuclear track detector (SSNTD) directly. However, such tracks can be formed through secondary particles created during primary radiation nuclear reactions in a SSNTD. Materials and Methods: The protons with primary energies of 9.6 and 30 MeV available at the cyclotron accelerator with corresponding lo...

Radiation track and DNA damage

A formalism for analysing large-scale clustering of radiation-induced breaks along chromosomes.

PURPOSE To model intrachromosomal clustering of DSB (DNA double strand breaks) induced by ionizing radiation. That DSB are located non-randomly along chromosomes after high LET irradiation, with clustering even at extremely large scales, has been confirmed by recent pulsed field gel electrophoresis data for size distributions of DNA fragments. We therefore extend the standard random-breakage mo...