[Medical and Dosimetric Register of the Siberian Group of Chemical Enterprises Personnel--the Basis for the Evaluation of Chronic, Radiation Exposure Effects].

The characteristic of medical and dosimetric register database of Siberian Group of Chemical Enterprises personnel is represented. This characteristic includes the description of the database structure, main sources of information, quantitative composition of the cohort under study, methods of evaluation of the external and internal irradiation doses, modern data on cancer incidence and reasons of death. The database is the basis for estimating the risk of the cancer and non-cancer effects after a long-term radiation exposure and dependence of "dose-response" at different levels: from population and group to cell and molecular. Now the database of register contains the information about more than 66,500 employees at the Siberian Group of Chemical Enterprises, about 22,000 of whom were exposed to external irradiation and more than 7500 employees--to internal irradiation. The register is the information resource of a large biological material bank. Using this bank, the research of chronic radiation exposure genetic effects and markers of individual radio sensitivity is performed.

[The frequency and spectrum of cytogenetic anomalies in employees of Siberian Group of Chemical Enterprises].

The results of the study of frequency and spectrum of cytogenetic anomalies in 657 healthy employees of the main facilities of the Siberian Group of Chemical Enterprises exposed to external, internal and combined irradiation are presented. No dependence between age and chromosome aberrations frequency was revealed. Chronic external exposure appeared to be the main factor of induction of chromosome aberrations. The frequency of aberrant cells, chromosome type aberrations, paired fragments and rings was statistically significantly higher in employees exposed to external irradiation as compared to persons exposed to combined irradiation. A nonlinear dependence the dose of irradiation and frequency of chromosome aberrations was revealed. A statistically significant decrease of prevalence of aberrant cells, aberration of chromatid and chromosome type was established in employees exposed to irradiation at a dose range of > 0-10 mSv compared to the control group. This agrees with the phenomenon of radiation hormesis. A significant increase of the frequency of chromosome aberrations was not observed at doses below > 40 mSv. In employees exposed to irradiation at a dose range > 40-100 mSv, a statistically significant increase of frequencies of aberrant metaphases, aberrations of chromatid and chromosome types was established. Same was found for dicentrics at dose range of >100-200 mSv. This supports a well known linear threshold model. Dose-effect curve has a plateau at doses ranged from 100 to 500 mSv.

[Data of coronary angiography and rheological properties of erythrocytes in non ST-elevation acute coronary syndrome].

We assessed character and extent of coronary vessels involvement in 27 patients with non ST-elevation acute coronary syndrome (NSTEACS) and compared angiography data with rheological properties of erythrocytes of patients and 30 practically healthy men. Stenoses of main branches of coronary vessels were found almost in 3/4 of cases. In 4 patients without stenoses in main branches of coronary arteries we revealed lowering of blood flow velocity related to small vessel disease (syndrome X). In 2 cases there were no changes in coronary circulation. Extent of vessel involvement was the least in patients with non Q-wave myocardial infarction as initial manifestation of ischemic heart disease and the greatest in patients with unstable angina after myocardial infarction. Patients with NSTEACS had elevated aggregation capacity and lowered deformability of erythrocytes. Degree of these changes did not depend on clinical peculiarities of development of the disease, extent of obstructions, character of vessels involvement. Positive correlation between was found content of cholesterol and degree of elevation of rate of erythrocyte aggregation.