[Radiation induced modification of human somatic cells chromosome sensitivity in testing mutagenic effect of bleomycin].

The voluntary investigation of hidden chromosome instability in 53 persons with different intensity of radiation exposure had been carried pout using modified "G2-bleomycin sensitivity assay". In all examined groups the individual levels of chromosome injuries under identical bleomycin exposure varied in wide range and didnrt depend on their initial values in the intact cultures. Among control donors and individuals with low radiation exposure approximately 33% hypersensitive persons had been identified that can be considered as genetically caused phenomenon. In patients recovered from acute radiation syndrome (57.9%) persons expressed hidden chromosome instability. The data permit to assume that high doses of ionizing radiation can modify inherited human chromosomes susceptibility to mutagen exposure.

[Chromosome instability revealed in children of fathers irradiated during Chernobyl accident].

Four children groups with and without thyroid pathology born to fathers exposed to ionizing irradiation in 1986 during Chernobyl accident as liquidators as well as residents of territory with radioactive contamination have been cytogenetically observed. The frequency and spectrum of chromosome aberrations in peripheral blood lymphocytes have been studied using two-termed cultivation (during 48 and 144 hours). Under the short-term incubation the observed groups did not significantly differ on the mean-group integral cytogenetic parameters which corresponded to age norm, but in progeny of parents from radionuclide contaminated territory the increased level of chromosome type exchanges has been revealed. In long-termed lymphocyte cultures of children with chronic thyroiditis the significantly increased cytogenetic effects of both chromatid (single fragments) and chromosome types (abnormal monocentrics, centric rings) have been established. The data received testified the reality of the transmissible chromosome instability phenomenon in progeny of irradiated parents and confirmed the possibility of its expression in consequent mitoses.

[The level of spontaneous chromosome aberrations in children from ecologically clean region of Ukraine studied with cytogenetic analysis of uniformly and differentially stained metaphase chromosomes]. / Riven' spontannykh khromosomnykh aberatsii u ditei z ekolohichno chystoho rehionu Ukraïny, vstanovlenyi pry tsytohenetychnomu analizi rivnomirno ta dyferentsiino zabarvlenykh metafaznykh khromosom.

The frequency of chromosome aberrations in children from Lviv region of Ukraine born after Chernobyl accident have been determined using conventional and G-banding staining.

[FISH detection of spontaneous level of chromosome aberrations in peripheral blood lymphocytes in persons of different ages]. / Spontannyi riven' aberatsii khromosom, vstanovlenyi v limfotsytakh peryferychnoï krovi osib riznoho viku za dopomohoiu metodu FISH.

FISH-WCP method with fluorescent probes to chromosomes 1, 2, 4 was used for cytogenetical examination of two groups of male (middle age 23 and 53.5 years) who deny their deliberate contact with known or supposed mutagens. The wide inter-individual variability of the stable chromosome aberration frequencies in each group has been shown (0.006-0.014 and 0.006-0.025 per cell per genome-equivalent correspondingly). The trend of increasing of the mean-group level of one-way and two-way translocations during aging has been revealed (0.009 and 0.013 per cell per genome-equivalent, correspondingly).

[Results of a cytogenetic study of children from radionuclide-contaminated goiter endemic zone of the Rivno region of Ukraine ]. / Rezul'taty tsytohenetychnoho obstezhennia ditei, iaki meshkaiut' na kontaminovanii radionukidamy terytoriï zony zobnoï endemiï Rivnens'koï oblasti Ukraïny.

Under the conventional cytogenetical examination of 6 different children groups (with and without non-stohastic thyroid pathology, exposed and nonexposed to the iodine isotopes in 1986) from the goiter endemic zone of Ukraine which belongs to the territory contaminated by 137Cs radionuclides, the identical to the spontaneous level of somatic chromosome mutagenesis of the last decade in all observed groups with the tendency to increasing of stable aberrations in some persons had been established.

[FISH analysis in verification of recorded doses in liquidators of Chernobyl accident]. / Vykorystannia metodu FISH dlia veryfikatsiï doz oprominennia u likvidatoriv Chornobyl's'koï avariï.

With the help of the FISH technique the Official Dose Records (ODR) in 40 liquidators from the National (18 persons) and Military (22 persons) Registers were verified. In the civil liquidators the cases with the overestimated individual ODR were predominated while in the liquidators from the Military Register the cases with underestimation of the ODR in comparison with biological irradiation doses were prevailed. The both groups were considered as true "high-dose" ones with radiation exposure that exceed permissible levels for an accident.

[Cytogenetic effect in peripheral blood lymphocytes of children living in villages in the Ovruch District, Zhitomir Region of the Ukraine contaminated by radionuclides]. / Tsytohenetichnyi efekt v limfotsytakh periferiinoï krovi ditei, shcho meshkaiut' v deiakykh naselenykh punktakh Ovruts'koho raionu Zhitomirs'koï oblasti Ukraïny, zabrudneniikh radionuklidamy.

For the purpose of genetic indication of low level of chronic radiation exposure the cytogenetic monitoring of some critical children groups living in two contaminated Ukrainian villages was carried out. In all the groups the mean frequency of aberrant cells and chromosome type aberrations (including dicentrics, centric rings, chromosome translocations as well as polyploid cells) significantly exceeded control level. During the repeated examination of children from Vistupovichi (in 13 months after the first one) the striking increase of cytogenetic effect was revealed. Dicentrics and rings were registered in 79% of persons with the individual rate 0.5-1.5 and mean group frequency 0.57 per 100 cells. The authors tried to evaluate the average cumulative doses of radiation for examined groups using G. Littlefield equation for dicentric outcome under the low dose rate Cs-137 source and taking into account the assumption about the reducing of 50% dicentrics per year. According to this rough calculation, the revealed cytogenetic effect can correspond to the mean total dose of 33 cSv for Vistupovichi children.