EFFECTIVENESS OF THE PHOTON CAPTURE BEAM TECHNOLOGY AND PHOTODYNAMIC IMPACT ON MALIGNANT HUMAN CELLS ІN A RESTING STATE. / ЕФЕКТИВНІСТЬ ФОТОН/ЗАХВАТНОЇ ПРОМЕНЕВОЇ ТЕХНОЛОГІЇ ТА ФОТОДИНАМІЧНОГО ВПЛИВУ НА ЗЛОЯКІСНІ КЛІТИНИ ЛЮДИНИ, ЩО ЗНАХОДЯТЬСЯ У СТАНІ СПОКОЮ.

OBJECTIVE: to investigate the structural and morphofunctional changes in test system of malignant (cell line A-549) human cells in a resting state exposed to X-rays in the presence of gadolinium-containing photon capture agent «Dotavist¼ and optical light (red spectrum) in combination with «Photolon¼ photosensitizer. METHODS: Passaged malignant human cell culture technology, X-ray and red light exposure, cytological and statistical methods. RESULTS: X-ray exposure at a dose of 10.0 Gy in the presence of photon capture agent «Dotavist¼ (at a 100 µg/ml nutrient medium concentration) led to death of 75-83 % of malignant cells in a resting state on the 6-8th day of cultivation. Photodynamic exposure (630 nm wavelength red light) in the presence of «Photolon¼ photosensitizer (200 µg/ml concentration) resulted in death of 69-73 % of malignant cells, respectively. Combination of the photon-capturing technology and photodynamic exposure resulted in death of 90 % of the malignant cells in a phase of steady-state growth on the 8th day of cultivation. CONCLUSION: Combination of the photon capture technology (X-ray exposure with gadolinium-containing photoncapture agent «Dotavist¼ in cytotoxic concentration) and photodynamic exposure in the presence of «Photolon¼ photosensitizer increased devitalization effectiveness of human non-small cell lung cancer cells (A-549 cell line) being in a steady-state growth phase up to 90 %. Ten percent of cells resistant to the applied technologies retained their proliferative potential, evident as changes in their morphology, genotype and adhesiveness during further cultivation.

EFFICIENCY OF PHOTON CAPTURE BEAM TECHNOLOGY AND PHOTODYNAMIC IMPACT ON MALIGNANT AND NORMAL HUMAN CELLS IN VITRO. / EFEKTYVNIST' FOTON-ZAKhVATNOÏ PROMENEVOÏ TEKhNOLOGIÏ TA FOTODYNAMIChNOGO VPLYVU NA ZLOIaKISNI TA NORMAL'NI KLITYNY LIuDYNY IN VITRO.

OBJECTIVE: to investigate the structural and morphofunctional changes in test systems of malignant (cell lineA549) and normal (stem fibroblasts) human cells exposed to X-rays in the presence of gadoliniumcontaining photon capture agent «Dotavist¼ and optical light (red spectrum) in combination with «Fotolon¼ photosensitizer. METHODS: The continuous cell culture of normal human fibroblasts and malignant human cells technology, X-ray and red light exposure, cytological and statistical methods. RESULTS: Effects of the two binary radiation technologies, namely the photon capture impact on malignant cells(human nonsmall cell lung cancer cells i.e. line A-549) and normal cells (human stem fibroblasts) when incubated with gadoliniumcontaining photon capture agent «Dotavist¼ and photodynamic effect in the presence of «Fotolon¼ photosensitizer applied separately and in combination were studied in a comparative mode. Proceeding from morphofunctional characteristics (growth kinetics, proliferative and mitotic activity) of the abovementioned test systems, peculiarities of the effect on malignant and normal cells were established. Irradiation with X-rays to the 1.0, 5.0, and 10.0 Gy doses resulted in inactivation of respectively 10 %, 46 %, and 80% of the A-549 line malignant cells.Cellular irradiation to a 1.0 Gy dose in the presence of the photon capture agent «Dotavist¼ (10 µl/ml concentration) inhibited cell proliferation by 50 %, suppressing their mitotic activity. At a dose of 10.0 Gy in the presence of «Dotavist¼ the inhibition by 93 % of the growth and division of malignant cells occurred, indicating the high efficiency of binary radiation technology. The effect of two binary radiation technologies on malignant human cells (A-549 line), namely the combination of red light with «Fotolon¼ (0.05 mg/ml concentration) and X-ray exposure in the above doses with «Dotavist¼ (10 µl/ ml concentration) resulted in the death of respectively 64 %, 86 %, and 99% malignant cells. The culture of normal fibroblasts was found being more sensitive to the influence of a complex of binary radiation impact, as exposure to a dose of 10.0 Gy in the presence of «Dotavist¼ and «Fotolon¼ inactivated 100 % of cells. CONCLUSION: The obtained results provide basis of preclinical evaluation of effectiveness of the combined impact of two binary technologies and drugs used in the photon capture technology and photodynamic therapy i.e. the photon capture agent «Dotavist¼ and «Fotolon¼ photosensitizer respectively.

NEUROENDOCRINE EFFECTS OF PRENATAL IRRADIATION FROM RADIOACTIVE IODINE (review). / NEY̆ROENDOKRYNNI EFEKTY PRENATAL'NOGO OPROMINENNIa RADIOAKTYVNYM Y̆ODOM (ogliad).

BACKGROUND: Neuroendocrine effects of the prenatal radiation exposure from radioactive iodine in an event of nuclear power reactor accidents are a key issue in the field of radiation medicine and radiation safety because of a dramatic radiosensitivity of the developing organism. OBJECTIVE: Review of contemporary epidemiological, clinical and experimental data on neuroendocrine effects of prenatal exposure to 131I. OBJECT AND METHODS: Search in the PubMed/MEDLINE and Google Scholar abstract databases, along with a manual search for the relevant data sources. RESULTS: Estimated absorbed doses of intrauterine thyroid irradiation from radioactive iodine were obtained based on ICRP Publication 88, both with estimates of effective radiation doses on embryo and fetus, and estimates of the brain equivalent doses upon exposure in utero. The latter ones are subject to updating. The evidence-based data has been presented regarding a radiation-associated reduction of head and chest circumference at birth, as well as a radiation-associated excess of goiter with large thyroid nodules, and possibly of thyroid cancer after a prenatal exposure to 131I radionuclides. Data on intrauterine brain damage are controversial, but most researchers share the view that there are cognitive and emotional-behavioral disorders due to prenatal and postnatal irradiation and psy- chosocial impacts. Incidence increase of non-cancerous endocrine disorders and degenerative vascular disease of retina was noted. An experimental model of intrauterine irradiation from 131I on Wistar rats was for the first time ever created, extrapolating the radioneuroembryological effects in rats to individuals prenatally exposed after the Chornobyl disaster. Late neuropsychiatric and endocrine effects may be resulted from the relatively short-term impact of ionizing radiation at a level previously been considered safe. The necessity of neuropsychiatric and endocrinological monitoring of individuals exposed prenatally to ionizing radiation after the Chornobyl catastrophe throughout their life is substantiated. Experimental animal studies are a key direction in the further research of radiation effects, especially associated with low radiation doses. Further experimental and clinical neuroradiobio- logical studies aimed at exploration of the effect of ionizing radiation on hippocampal neurogenesis are most rele- vant nowadays.

Experimental evaluation of 2-merkaptobenztyazol radioprotective capacities on cell cultures test system. / EKSPERYMENTAL'NA OTsINKA RADIOPROTEKTORNYKh VLASTYVOSTEi 2-MERKAPTOBENZTIAZOLU U TEST-SYSTEMI KUL'TURY KLITYN.

OBJECTIVE: To study the radioprotective properties of 2-merkaptobenztyazol on proliferating cell culture test system. MATERIALS AND METHODS: cytogenetic, cytological, statistics. RESULTS: Analysis of cytogenetic effects of 2-merkaptobenztiazol by frequency aberrations criteria and aberrant cells damage criteria showed that upon entire investigated range of reagent concentrations the frequency of aberrations was not significantly higher than the value of this indicator in control, but there was a tendency of reduction of mitotic activity of root meristem cells. Upon the incubation of inoculated cell line L929 with 2-merkaptobenztiazolom in the concentration range 0.03 - 3.00 mg/ml statistically significant change (r≤0,05) of cell population density in monolayer cultures was found. At the same time for all the applied reagent concentrations stimulation of mitotic activity in the terminal (5 days) stage of cultivation was observed. Exposure of cells by gamma quanta of 60Co in doses of 1, 5 and 10 Gy led to dose-dependant morphological changes in cell culture. Exposure of cells in the presence of 2-merkaptobenztiaz significantly reduced the negative impact of radiation on cell viability parameters in cultureConclusions. Quantifying radioprotective properties of 2-merkaptobenztyazol in the test system - cell cultureL929 - showed that the highest rates of protection factor (0, 31 - 0.36) reagent had at a concentration of 3 mg/ml under the irradiation at a 1Gy dose. However, dose reduction factor (DRF) calculated by LD50 for concentrations of 0.03 and 0.30 mg/ml had a value of 1.5 and 1.8 respectively, and the concentration of 3.00 mg/ml DRF was the maximum - 4.The literature study and the results of our own research showed that 2 merkaptobenztiazol can be considered to be reagent with radioprotective properties for cells in vitro.