[Early medical consequences of the radiation accidents in the former USSR Territory].

The paper sums up the information on radiation incidents at the former USSR territory, which incidents are related to the human exposure of clinically significant effects. Within more than 60 years (since 1949), at least 356 radiation incidents accompanied by the clinically significant human exposure have happened at the former USSR territory, which has resulted to clinically significant health effects in 765 victims. This exposed cohort includes 348 acute radiation sickness (ARS) patients including cases aggravated by local radiation injuries (LRI). 407 victims were affected by local radiation injuries only. Totally, 71 radiation induced fatalities were observed within first 3-4 months after the irradiation. The maximum adverse effects as a result of accidental exposure of radiation incidents in the former USSR territory, had a place for professional workers whose work is associated with sources of ionizing

[The bioavailability of zinc oxide nanoparticles. Study using methods of radionuclide indicators].

Zinc oxide nanoparticles labeled with 65Zn were administered once intragastrically to male Wistar rats. The distribution of radionuclide-marker (65Zn) was measured by gamma-spectrometer in tissue samples of animals the organs through 4 hours, 1, 3 and 5 days after administration, and in the wastes of animals through 1 since 5 days. The data obtained demonstrate for the first time the bioavailability of zinc trace element in the form of its oxide nanoparticles.

[Early leukemia effect during chronic exposure to radiation with high doses].

The preliminary results of the analysis of leukemia morbidity in the sub-cohort of workers from PA "Mayak" exposed with high (more than 4Gy) doses during relatively short time range (few years) have been obtained in terms of materials from the medical-dosimetry register (SUrIBPh). The earlier dynamics of the leukemia morbidity implementation (2-5 years after the beginning of exposure) was established for this sub-cohort, in contrast to that predicted on the base of examination of the cohort of atomic bombardment victims from Japan cities (LSS). The "'early" leukemia effect is connected with intensive cell death and has a threshold nature. It could be supposed, that intensification of born-marrow hematopoetics restricts a potential of reparation processes and leads to earlier (in contrast with that observed in the LSS cohort) implementation of carcinogenetic effect. Using propositions developed to describe the process of the creation of consecutive specific stable mutation in the target cells, the options is proposed of multistage model, which allows the prediction of post-radiation dynamics of leukemia morbidity intensity. Both data from LSS(DS86) and from the register for workers from PA "Mayak" were used to asses the model parameters. The satisfactory agreement is illustrated between the observed dynamics of leukemia morbidity and the model calculations.

[Infection syndrome in acute radiation sickness patients subjected to Chernobyl accident].

In spite of intensive antimicrobial prophylaxis and therapy, most patients with acute radiation sickness I-IV severity grade (dose of 0.1-13.7 Gy) developed infections caused by bacteria, fungi and viruses. Frequency and intensity of those infections were proportional to the radiation dose and severity grade of radiation sickness.

[Reaction of the blood forming system of the dogs to acute radiation exposure (by the SRC-Institute of biophysics data bank)]. / Reaktsiia krovetvornoi sistemy sobak na ostroe radiatsionnoe vozdeistvie (po materialam bazy dannykh GNTS-Institut biofiziki MZ RF).

At present time in the SRC--Institute of Biophysics the data bank containing the information on the reactions of 431 dogs to radiation exposure in a wide range of doses has been created. By the results of 4299 blood tests reporting a leukocyte content, including 2509 tests reporting a blood formula, the individual peculiarity of the peripheral blood reaction in dogs were analyzed. Dose dependencies for the reaction of blood-forming system to radiation exposure to doses in the range from 1.0 to 7.0 Gy were obtained. In comparison with the similar data for humans, the neutrophil content in peripheral blood decreased approximately 1.5-2.0 times faster in dogs than in men, resulting in earlier recovery.

[Instrumentation for ultrasound diagnosis of vascular diseases]. / Pribory dlia ul'trazvukovoi diagnostikoi sosudistykh zabolevanii.

The paper describes the computer-based ultra-sound medical instruments worked out by the authors to diagnose the diseases and traumas of the brain, vessels, arteries and cerebral veins as well as of pathologies of the upper and lower extremities. The portable instruments are capable of four diagnostic methods: echoencephalography, echopulsegraphy as well as ultra-sound and transcranial Doppler-graphy.

[The relation of the times of onset of vomiting to the magnitude and power of the dose of ionizing radiation]. / Zavisimost' srokov vozniknoveniia rvoty ot velichiny i moshchnosti dozy ioniziruiushchego izlucheniia.

The paper is concerned with analysis of correlation of the time of appearance of vomit in a person and a mean dose rate of prolonged gamma-radiation in the persons affected at the Chernobyl accident. The data were approximated by power function. For irradiation with a constant dose rate (P) such correlation looks like Tp = 2.48p-0.5, where Tp is the time of the beginning of vomit, hours after the beginning of irradiation. A semiempirical model combining different conditions of irradiation was formed. Prognosis of a severity of lesion with relation to the time of vomit was given for different conditions of irradiation.

[Neutrophil and lymphocyte dose curves in relatively uniform human whole body irradiation (based on data of the accident at the Chernobyl AES)]. / Doznye krivye neitrofilov i limfotsitov pri obshchem otnositel'no ravnomernom gamma-obluchenii cheloveka (po materialam avarii na Chernobyl'skoi AES).

The authors have summed up the experience in a study of regularities of the bone marrow syndrome in persons exposed to rather homogeneous gamma-beam irradiation during the accident at the Chernobyl Nuclear Power Station (127 cases). Hematological data were processed by computer, and empiric dose curves of neutrophils and lymphocytes were obtained within the range of 0.5-12 Gy by regressive analysis. These curves were compared with the previous data on the time course of these cells after whole-body irradiation. New data were obtained on the nature of a course of a granulocyte recovery phase at a dose level over 5 Gy. Some features of the time course of lymphocytes in persons exposed to radiation during the accident at the Chernobyl Nuclear Power Station, were considered.

[The direct use of cytogenetic data for plotting prognostic curves of the dynamics of neutrophil count after acute relatively uniform gamma irradiation (based on data from the victims of the accident at the Chernobyl Atomic Electric Power Station]. / Priamoe ispol'zovanie tsitogeneticheskikh dannykh dlia postroeniia prognosticheskikh krivykh dinamiki chisla neitrofilov posle ostrogo otnositel'no ravnomerno gamma-oblucheniia (na materiale postradavshikh pri avarii na Chernobylskoi AES).

A considerable number of irradiated persons appeared as a result of the accident at the Chernobyl Atomic Power Station. Analysis of chromosome aberrations and detailed hematological investigations were performed in them. Relatively uniform affection of the hemopoietic tissue could be anticipated on the basis of the results of the cytogenetic analysis in most of these persons who had been exposed to radiation at doses that were critical for the development of the bone marrow syndrome. It made it possible to establish direct quantitative relationship between the indices of a postradiation curve of the time course of the neutrophil count in peripheral blood and the mean rate of dicentrics in lymphocytes for cases of relatively uniform irradiation and to plot prognostic curves of neutrophils for different frequencies of dicentrics.

[Estimation of the critical level of an arrest in differentiation of human hematopoietic stem cells]. / Otsenka kriticheskogo urovnia "zapreta na differentsirovku" chislennosti stvolovykh krovetvornykh kletok cheloveka.

On the basis of the analysis of postirradiation changes in the specific number human peripheral blood neutrophils the authors have estimated the level of the "arrest of differentiation" (AD) of their precursors (haemopoietic stem cells (HSC) which amounted to 0.2-0.9% of their normal number at a local functional site of haemopoiesis. The time of the onset of AD, with subcritical doses (to 6.4-8.8 Gy) leading to HSC pool depletion, which does not reach a critical level, decreases linearly with dose, and its duration is practically independent of the dose and makes up 10 (6 to 16) days on an average.