Investigation on the correlation between energy deposition and clustered DNA damage induced by low-energy electrons
Language
en
Article de revue
This item was published in
Radiat.Environ.Biophys. 2018, vol. 57, n° 2, p. 179-187
English Abstract
This study presents the correlation between energy deposition and clustered DNA damage, based on a Monte Carlo simulationof the spectrum of direct DNA damage induced by low-energy electrons including the dissociative ...Read more >
This study presents the correlation between energy deposition and clustered DNA damage, based on a Monte Carlo simulationof the spectrum of direct DNA damage induced by low-energy electrons including the dissociative electron attachment.Clustered DNA damage is classified as simple and complex in terms of the combination of single-strand breaks (SSBs) ordouble-strand breaks (DSBs) and adjacent base damage (BD). The results show that the energy depositions associated withabout 90% of total clustered DNA damage are below 150 eV. The simple clustered DNA damage, which is constituted of thecombination of SSBs and adjacent BD, is dominant, accounting for 90% of all clustered DNA damage, and the spectra of theenergy depositions correlating with them are similar for different primary energies. One type of simple clustered DNA damageis the combination of a SSB and 1–5 BD, which is denoted as SSB+BD. The average contribution of SSB+BD to totalsimple clustered DNA damage reaches up to about 84% for the considered primary energies. In all forms of SSB+BD, theSSB+BD including only one base damage is dominant (above 80%). In addition, for the considered primary energies, there isno obvious difference between the average energy depositions for a fixed complexity of SSB+BD determined by the numberof base damage, but average energy depositions increase with the complexity of SSB+BD. In the complex clustered DNAdamage constituted by the combination of DSBs and BD around them, a relatively simple type is a DSB combining adjacentBD, marked as DSB+BD, and it is of substantial contribution (on average up to about 82%). The spectrum of DSB+BD isgiven mainly by the DSB in combination with different numbers of base damage, from 1 to 5. For the considered primaryenergies, the DSB combined with only one base damage contributes about 83% of total DSB+BD, and the average energydeposition is about 106 eV. However, the energy deposition increases with the complexity of clustered DNA damage, andtherefore, the clustered DNA damage with high complexity still needs to be considered in the study of radiation biologicaleffects, in spite of their small contributions to all clustered DNA damage.Read less <
Origin
Hal imported