caa a22 4500 44581294X CHVBK 20180317145217.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s00411-011-0360-2 doi (NATIONALLICENCE)springer-10.1007/s00411-011-0360-2 Chromosome aberration measurements in mitotic and G2-PCC lymphocytes at the standard sampling time of 48h underestimate the effectiveness of high-LET particles [Elektronische Daten] [Ryonfa Lee, Elena Nasonova, Carola Hartel, Marco Durante, Sylvia Ritter] The relationship between heavy-ion-induced cell cycle delay and the time-course of aberrations in first-cycle metaphases or prematurely condensed G2-cells (G2-PCC) was investigated. Lymphocytes of the same donor were irradiated with X-rays or various charged particles (carbon, iron, xenon, and chromium) covering an LET range of 2-3,160keV/μm. Chromosome aberrations were measured in samples collected at 48, 60, 72, and 84h postirradiation. Linear-quadratic functions were fitted to the data, and the fit parameters α and β were determined. At any sampling time, α values derived from G2-cells were higher than those from metaphases. The α value derived from metaphase analysis at 48h increased with LET, reached a maximum around 155keV/μm, and decreased with a further rise in LET. At the later time-points, higher α values were estimated for particles with LET>30keV/μm. Estimates of α values from G2-cells showed a similar LET dependence, yet the time-dependent increase was less pronounced. Altogether, our data demonstrate that heavily damaged lymphocytes suffer a prolonged G2-arrest that is clearly LET dependent. For this very reason, the standard analysis of aberrations in metaphase cells 48h postirradiation will considerably underestimate the effectiveness of high-LET radiation. Scoring of aberrations in G2-PCC at 48h as suggested by several authors will result in higher aberration yields. However, when particles with a very high-LET value (LET>150keV/μm) are applied, still a fraction of multiple damaged cells escape detection by G2-analysis 48h postirradiation. Springer-Verlag, 2011 Lee Ryonfa Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut Nasonova Elena Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut Hartel Carola Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut Durante Marco Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut Ritter Sylvia Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut Radiation and Environmental Biophysics Springer-Verlag 50/3(2011-08-01), 371-381 0301-634X 50:3<371 2011 50 411 https://doi.org/10.1007/s00411-011-0360-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s00411-011-0360-2 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lee Ryonfa Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut NATIONALLICENCE 700 1- Nasonova Elena Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut NATIONALLICENCE 700 1- Hartel Carola Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut NATIONALLICENCE 700 1- Durante Marco Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut NATIONALLICENCE 700 1- Ritter Sylvia Biophysics Department, GSI Helmholtzzentrum für Schwerionenforschung, Planckstraße 1, 64291, Darmstadt, Germany aut NATIONALLICENCE 773 0- Radiation and Environmental Biophysics Springer-Verlag 50/3(2011-08-01), 371-381 0301-634X 50:3<371 2011 50 411 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer