Factors influencing chromosome aberration yields in the human peripheral leukocyte system

The Oxygen Enhancement Ratio for X-ray-induced Chromosomal Aberrations in Cultured Human Lymphocytes

“…The yield of dicentric chromosomes and Cu cells, in all cultures, reached a maximum after incubation for 60 hours. A similar initial increase of aberration yield with time in culture has been recently reported for non-gassed irradiated lymphocytes (Bender and Brewen 1969). No scorable metaphase lymphocytes and, in most cultures, no mitotic cells were observed at 40 hours in culture.…”

Cell cycle analysis and properties of two sub-populations in PHA responding lymphocytes

“…Recently various investigations have indicated the presence of at least two subpopulations in human PHA-stimulated lymphocyte cultures (Michalowski, 1963;Bender and Brewen, 1969;Steffen and Michalowski, 1973;Dudin et al, 1974). The In the present experiments the MLI curves of the first post-labelling mitosis were very resembled one another in the trisomic and control cells, respectively.…”

“…However, no difference was found between the two sub-populations either in the trisomic or normal groups. Bender and Brewen (1969) suggested that in normal lymphocyte cultures a cell sub-population which entered earlier into mitosis after PHA-stimulation might be more sensitive concerning the induction of dicentrics and rings by ionizing radiations. Similar evidence for the production of chromosome aberrations has been indicated by Beek and Obe (1974) in their experiments treated together with aH-TdR and an alkylating agent, A 139 (2,5-bis-(methoxyethoxy)-3,6-bis-(ethyleneimino)-p-benzoquinone).…”

Chromosome aberrations as a measure of mutagenesis: cytogenetic extrapolation from animal to man

“…In the experiments of Bianchi et al (1979), the lymphocytes in the first division at 40, 44, and 72 h after the start of culture had a lower sensitivity to radiation than lymphocytes making their first division at 48, 52, and 56 h, some of the individuals studied by van Buul and Natarajan (1980) showing little variation with sampling time and others showing strong variation. It is difficult to consider these results as de monstrating the existence of subpopulations of lymphocytes displaying differential radio sensitivity, a hypothesis which was already proposed several years ago (Bender and Brewen, 1969;Steffen and M ichalowski, 1973;Beek and O be, 1976). A constant yield of dicentrics in Ml cells, independent of the time of harvest, was, indeed, ob served by Scott and Lyons (1979) and Leonard and D ecat (1979).…”