CYTOGENETIC STUDY OF MANIFESTATIONS OF THE UNIVERSAL PHENOMENON OF THE BYSTANDER RESPONSE.

Objective: to establish the level of chromosomal instability in peripheral blood lymphocytes (PBL) from healthyindividuals and cells from patients with B-cell chronic lymphocytic leukemia (CLL) under co-cultivation conditions and to determine the possibility of inducing manifestations of the universal phenomenon of bystander response in them.

Materials And Methods: Cytogenetic analysis of uniformly stained chromosomes from human PBL, which differed by cytogenetic markers of sex; the presence of oncological transformation and in vitro irradiation of 137Cs in a dose of 0.50 Gy under the conditions of their joint cultivation was performed.

MODIFICATION OF THE TUMOR/INDUCED BYSTANDER EFFECT BY IRRADIATION UNDER COCULTIVATION OF LYMPHOCYTES FROM PATIENTS WITH CHRONIC LYMPHOCYTIC LEUKEMIA AND LYMPHOCYTES FROM HEALTHY DONORS.

Objective: Study the tumor-induced bystander effect of blood cells from chronic lymphocytic leukemia (CLL)patients on non-transformed bystander cells (peripheral blood lymphocytes (PBL) of conditionally healthy individ-uals) and the possibility of its modification after the impact of ionizing radiation.

Materials And Methods: We carried out cocultivation and separate cultivation of blood samples from conditionallyhealthy volunteers and patients with CLL according to our technique. Using the Comet assay, the relative level ofDNA damage was evaluated.

Study of modifying effects of astaxanthin on cytogenetic manifestations of bystander response in human peripheral blood lymphocytes in vitro.

Aim: To study the possible impact of astaxanthin on the cytogenetic manifestations of the simultaneous development of radiation-induced (RIBE) and tumor-induced bystander effect (TIBE) in human peripheral blood lymphocytes.

Materials And Methods: Peripheral blood lymphocytes from healthy persons and patients with chronic lymphocytic leukemia were cultured separately or cocultured with or without previous irradiation in vitro by Cs at a dose of 0.5 Gy.

STUDY THE EFFECTS OF IONIZING RADIATION ON THE LEVEL OF CHROMOSOME INSTABILITY IN HUMAN SOMATIC CELLS DURING THE DEVELOPMENT OF TUMOR-INDUCED BYSTANDER EFFECT.

Objective: to determine the impact of the irradiated in vitro blood cells from patients with B-cell chronic lymphocytic leukemia (CLL) on the level of chromosomal instability in peripheral blood lymphocytes (PBL) from healthy persons during the development of tumor-induced bystander effect.

Materials And Methods: Separate and joint cultivation of PBL from healthy persons (cells-bystanders) together withblood cells from CLL patients irradiated in vitro at the G0 stage of the mitotic cycle by γ-quanta 137Cs in a dose of0.5 Gy 137Cs (cells-inductors) was used.

RADIATION-INDUCED BYSTANDER EFFECT - MODELING, MANIFESTATION, MECHANISMS, PERSISTENCE, CANCER RISKS (literature review).

The review summarizes and analyzes the data of world scientific literature and the results of the own research con- cerning one of the main non-targeted effects of ionizing radiation - the radiation induced bystander effect (RIBE) - the ability of irradiated target cells to induce secondary biological changes in non-irradiated receptor cells. The his- tory of studies of this phenomenon is presented - it described under various names since 1905, began to study from the end of the twentieth century when named as RIBE and caused particular interest in the scientific community during recent decades. It is shown that the development of biological science and the improvement of research methods allowed to get new in-depth data on the development of RIBE not only at the level of the whole organism, but even at the genome level.

DEVELOPMENT OF RADIATION-INDUCED BYSTANDER EFFECT IN THE SOMATIC CELLS OF PERSONS FROM DIFFERENT AGE GROUPS.

Objective: To investigate the development of chromosomal instability as a result of the radiation-induced bystandereffect in blood lymphocytes of persons from different age groups.

Materials And Methods: Materials of research were blood lymphocytes from 42 persons of different age (from 12 to102 years), divided into four age groups - teenagers, middle-aged, elderly and centenarians. Bystander effect wasstudied by modeling its induction in human lymphocytes, at which 0.

BIOLOGICAL MARKERS OF EXTERNAL AND INTERNAL EXPOSURE IN SHELTER CONSTRUCTION WORKERS: A 13-YEAR EXPERIENCE.

Objective: The aim of this study is to investigate the cellular, molecular, genetic and non-invasive functional biomarkers of occupational irradiation in workers exposed to a combination of external gamma-radiation and incorporation of transuranium elements.

Results: A study was performed in 688 radiation workers of Shelter object conversion into a safe system with mean shift dose of external exposure of 26.06 mSv (range: 0.

Comparative analysis the frequency and spectrum of chromosome aberrations in irradiated in vitro peripheral blood lymphocytes of the elderly and centenarians from Kyiv.

Objective: To establish and compare the frequency and spectrum of chromosome aberrations under X radiation exposure in vitro in dose 0.25 Gy peripheral blood lymphocytes of the elderly and centenarians.

Material And Methods: Material of cytogenetic research were peripheral blood lymphocytes from 11 elderly and 10 centenarians, which were irradiated in vitro in dose 0.

Study the impact of astaxanthin on developing of genomic instability in human peripheral blood lymphocytes irradiated in vitro on G2 phase of cell cycle.

Objective: To identify the possibility of modification by astaxanthin the level of genome damages induced by gamma quanta in the culture of human peripheral blood lymphocytes exposed in vitro on postsynthetic (G2) phase of the first mitotic cycle.

Materials And Methods: Peripheral blood lymphocytes from four apparently healthy volunteers 35-51 years old were cultivated using modified micromethod. To obtain genomic damages in G2 phase of the first mitotic cycle the part of cultures was irradiated by γ quanta in dose 1.

Chromosomal mutagenesis in human somatic cells: 30-year cytogenetic monitoring after Chornobyl accident.

In the lecture we have generalized and analyzed the data of cytogenetic laboratory of National Research Center for Radiation Medicine of the National Academy of Medical Sciences of Ukraine on 30-year selective cytogenetic monitoring among the priority contingents of different ages exposed to radiation after Chornobyl accident in Ukraine. It is highlighted that not only targeted but also untargeted radiation-induced cytogenetic effects should be explored, especially in delayed terms following radiation exposure. The new methodical approaches for studying "bystander effect", individual radiosensitivity, and various forms of radiation-induced chromosomal instability (delayed, hidden, transmissible) have been proposed.

Astaxanthin modifies clastogenic effects of ionizing radiation in vitro in peripheral blood lymphocytes of the persons recovered from acute radiation sickness.

Aim: To assess radioprotective activity of astaxanthin toward radiation-induced in vitro cytogenetic effects in human peripheral blood lymphocytes (PBL).

Materials And Methods: PBL from the cleanup workers exposed to ionizing radiation at high doses in 1986 during accident on Chornobyl nuclear power plant and who were diagnosed with acute radiation sickness of the first and second degrees, were cultured in vitro. Astaxanthin was added into the culture medium at a final concentration of 20.

Genoprotective properties of astaxanthin revealed by ionizing radiation exposure in vitro on human peripheral blood lymphocytes.

Objective: to identify possible radioprotective properties of astaxanthin by means of cytogenetic criteria.

Methods: Cultivation of peripheral blood lymphocytes from five apparently healthy volunteers; treatment of lym phocytes' cultures by astaxanthin in final concentrations 20 μg/ml in Go phase of mitotic cycle, prior to ? irradia tion in vitro in a dose 1 Gy; cytogenetic analysis the uniformly stained slides of metaphase chromosomes. The elec trophoresis of individual cells (Comet assay); visualization of results under fluorescent microscope; accounting the number of nucleoid the fourth grade that correspond to apoptosis of the cells.

Peculiarities of induction and persistence of hidden chromosome instability in peripheral blood lymphocytes of persons occupationally exposed to ionizing radiation.

Objective - to investigate the induction of hidden chromosome instability in persons occupationally exposed to ionizing radiation and its persistence in vitro in successive mitoses. Materials and methods. Using two tests ("G2-bleomycin sensitivity assay" and two-term cultivation of human peripheral blood lymphocytes) voluntary cytogenetic examination of 15 individuals participated in the conversion of the "Shelter" ("Chornobyl NPP") into ecologically safe system had been carried out.

[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.

[Radiation-induced bystander effect].

Data concerning induction mechanisms, the objects and methods of investigation of a non-target radiobiological phenomenon bystander effect, its role in radiation-induced genomic instability and oncogenesis are summarized.

[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.

[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].

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].

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.

[Chromosome aberration frequency in children with chronic thyroiditis born before and after the accident at the Chernobyl nuclear reactor].

Children with chronic thyroiditis born before and after Chernobyl accident have been investigated cytogenetically using G-banding staining. It was shown that the chromosome instability and sensitivity to cesium radioisotopes increased and the pathological process in a thyroid gland implemented in persons exposed to 131I in their childhood and living in iodine-deficient territories.

[Results of a cytogenetic study of children from radionuclide-contaminated goiter endemic zone of the Rivno region of Ukraine ].

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].

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.

[Comparison of the possibilities of micronuclear and chromosomal aberration tests for evaluation of the effects of radiation of different intensities].

The comparative evaluation of sensitivity and specificity of the micronucleus and chromosome aberration tests for human lymphocytes at the delayed terms after acute exposure to high-dose as well as during constant exposure to low-dose gamma-radiation has been done. Accordance between these tests registered only in the cases of acute radiation sickness of second and third degrees of severity (irradiation doses above 200 cGy). Unspecificity of micronucleus test for estimation of the radiation load under constant low-intensity irradiation was found.

[The detection of stable and unstable markers of radiation action in persons with a history of chronic irradiation using the methods of routine and differentiated staining of metaphase chromosomes].

A comparative cytogenetic observation of a group from Chernobyl NPP personnel has been carried out using conventional and G-banding staining. Detection rate of stable aberration by conventional staining to G-banding was 0.20.

[Cytogenetic effect in peripheral blood lymphocytes of children living in villages in the Ovruch District, Zhitomir Region of the Ukraine contaminated by radionuclides].

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.