A control mechanism that limits nuclear division is pres ent in contact-inhibited nontumorigenic mouse BALB/3T3 cells and mouse embryo fibroblasts. In the absence ofcytoplasmic division, 3T3 and mouse embryo fibroblast cells may undergo nuclear division once or occasionally twice and then stop. Also, there is no increase in the frequency of premature chromosome condensation. In non-contactinhib...

A control mechanism that limits nuclear division is pres ent in contact-inhibited nontumorigenic mouse BALB/3T3 cells and mouse embryo fibroblasts. In the absence ofcytoplasmic division, 3T3 and mouse embryo fibroblast cells may undergo nuclear division once or occasionally twice and then stop. Also, there is no increase in the frequency of premature chromosome condensation. In non-contactinhib...

A possibility of molecular-nuclear transitions to occur was recently predicted for some few-atomic systems. Among others, the molecule of ordinary water was shown to be a candidate for this effect due to a presence of (1, 4.522 MeV)-resonance in the Ne nucleus. The search for traces of nuclear reactions was carried out for condensed and vaporous phases of water, with the use of low-background a...

We measured mitosis-promoting factor (MPF) activity in two cell lines, CHO and HeLa, extensively used at mitosis as inducers in the assay of premature chromosome condensation to study the yield and the repair kinetics of radiation damage in interphase chromosomes of diverse cell lines. We found a 2.5-fold higher MPF activity in HeLa as compared to CHO mitotic cells per mg of crude extract prote...

We measured mitosis-promoting factor (MPF) activity in two cell lines, CHO and HeLa, extensively used at mitosis as inducers in the assay of premature chromosome condensation to study the yield and the repair kinetics of radiation damage in interphase chromosomes of diverse cell lines. We found a 2.5-fold higher MPF activity in HeLa as compared to CHO mitotic cells per mg of crude extract prote...

Cells of higher eukaryotes process double strand breaks (DSBs) in their genome using a non-homologous end joining apparatus that utilizes DNA-PK and other well characterized factors (D-NHEJ). Cells with defects in D-NHEJ, repair the majority of DSBs using a slow-repair pathway which is independent of genes of the RAD52 epistasis group and functions as a backup (B-NHEJ). Recent studies implicate...

The phenomenon of premature chromosome condensation (PCC) was used to compare the bone marrow proliferation characteristics of 163 patients with various forms of leukemia prior to the initiation of new therapy. The proliferative potential index (PPI, or fraction of G1 cells in late G1 phase) and the fraction of cells in S phase was determined and compared to the type of disease and the bone mar...