Contribution of Indirect Effects to Clustered Damage in DNA Irradiated with Protons

0450488 - ÚJF 2016 RIV GB eng J - Journal Article
Pachnerová Brabcová, Kateřina - Štěpán, Václav - Karamitros, M. - Karabín, M. - Dostálek, P. - Incerti, S. - Davídková, Marie - Sihver, L.
Contribution of Indirect Effects to Clustered Damage in DNA Irradiated with Protons.
Radiation Protection Dosimetry. Roč. 166, 1-4 (2015), s. 44-48. ISSN 0144-8420. E-ISSN 1742-3406
R&D Projects: GA MŠMT LD12008; GA MŠMT LM2011019
Grant - others:GA MŠk(CZ) LM2010005
Institutional support: RVO:61389005
Keywords : Geant4-DNA * radiolysis * breakage * lesions * cells
Subject RIV: BO - Biophysics
Impact factor: 0.894, year: 2015

Protons are the dominant particles both in galactic cosmic rays and in solar particle events and, furthermore, proton irradiation becomes increasingly used in tumour treatment. It is believed that complex DNA damage is the determining factor for the consequent cellular response to radiation. DNA plasmid pBR322 was irradiated at U120-M cyclotron with 30 MeV protons and treated with two Escherichia coli base excision repair enzymes. The yields of SSBs and DSBs were analysed using agarose gel electrophoresis. DNA has been irradiated in the presence of hydroxyl radical scavenger (coumarin-3-carboxylic acid) in order to distinguish between direct and indirect damage of the biological target. Pure scavenger solution was used as a probe for measurement of induced OH center dot radical yields. Experimental OH center dot radical yield kinetics was compared with predictions computed by two theoretical models-RADAMOL and Geant4-DNA. Both approaches use Geant4-DNA for description of physical stages of radiation action, and then each of them applies a distinct model for description of the pre-chemical and chemical stage.
Permanent Link: http://hdl.handle.net/11104/0251796