[Experimental assessment of embryotoxic action of low intensity ionizing irradiation in different periods of intrauterine development].

The prolonged ionizing radiation exposure at the absorbed doze rate of 2.6 mGy/hour and the total accumulated doze of about 20 cGy during different periods of the intrauterine development caused disorders of a coordinated development of organs and the decrease of endurance in physical activity in the postnatal ontogenesis of the irradiated posterity. The results obtained are comparable to the consequences of irradiation exposure of the fetus at the accumulated doze of 125 cGy during all stages of pregnancy and give grounds for considering radiation exposure at the above-mentioned rate (20 cGy) as a biologically significant factor.

[Influence of peptide derivatives of diketopiperazines on hemopoietic stem cells of an intact organism and irradiated bone marrow cells in vitro].

We have performed structural and functional studies of the hemotropic activity for a number of novel 2,5-diketopiperazine peptidomimetic derivatives. We employed a mouse model of hemopoietic stem cells cloning in the spleen of lethally irradiated animals. Biologic activity of synthetic products was studied in two experimental models: 1) in vitro irradiated bone marrow SFU-S was used for studying the radio modifying activity; 2) the biological effect of peptidomimetics on the intact non-irradiated bone marrow was evaluated in vivo. Various ways of administration of the peptidomimetics studied were used in the in vivo experiments: intravenous, intraperitoneal or subcutaneous injections and oral administration in the dose range of 10-10000 microg/kg. As a result of our work, we have discovered 2,5-diketopiperazine peptidomimetic derivatives with the dual activity: stimulation of intact committed SFU-S and radiomodifying activity.

[Increase in Ca(2+)-permeability of the plasma membrane during radiation-induced apoptosis of thymocytes]. / Uvelichenie pronitsaemosti plazmaticheskoi membrany dlia Ca(2+) pri radiatsionno-indutsirovannom apoptoze timotsitov.

The parameters of Ca(2+)-permeability (rate of Ca2+ influx in the presence of Ca(2+)-ATPase blocker vanadate and initial rate of Ca2+ uptake) were determined in the rat thymocytes after induction of apoptosis in vitro by gamma (gamma-irradiation at 5 Gy. There were no changes in the rate of Ca(2+)-influx within 30 to 909 min after irradiation, thus suggesting passive membrane permeability, while the initial rate of Ca(2+)-uptake, which characterizes Ca(2+)-exchange, approximately doubled in the irradiated cells. Thereafter, the initial rate of Ca(2+)-uptake in the intact and irradiated thymocytes became equal, while the rate of Ca(2+)-influx in the irradiated cells increased reliably 1.5-2 times within 90-180 min. Modification of membrane permeability for Ca2+ in the irradiated thymocytes precedes initiation of DNA degradation, and passive permeability is increasingly disturbed as apoptosis progresses. These data suggest that disturbances in Ca2+ passive permeability and intracellular Ca2+ homeostasis are an apoptosis trigger in lethally irradiated thymocytes.

[Organizational and economic aspects of psychiatry]. / Organizatsionnyi i ékonomicheskii aspekty psikhiatrii.

The main trends in the organization and economic transformations in psychiatric services of Russia in 1989-1996 are analyzed: financial support of the institutions of psychiatric care, changes in the organizational structure of services, new forms and types of care. The opinion of the authorities of regional services concerning the organization and economic changes in institutions of psychiatric care are presented.

Natural hidden antibodies reacting with DNA or cardiolipin bind to thymocytes and evoke their death.

Both free and hidden natural antibodies to DNA or cardiolipin were obtained from immunoglobulins of a normal donor. The free antibodies reacting with DNA or cardiolipin were isolated by means of affinity chromatography. Antibodies occurring in an hidden state were disengaged from the depleted immunoglobulins by ion-exchange chromatography and were then affinity-isolated on DNA or cardiolipin sorbents. We used flow cytometry to study the ability of free and hidden antibodies to bind to rat thymocytes. Simultaneously, plasma membrane integrity was tested by propidium iodide (PI) exclusion. The hidden antibodies reacted with 65.2 +/- 10.9% of the thymocytes and caused a fast plasma membrane disruption. Cells (28.7 +/- 7.1%) were stained with PI after incubation with the hidden antibodies for 1 h. The free antibodies bound to a very small fraction of the thymocytes and did not evoke death as compared to control without antibodies. The possible reason for the observed effects is difference in reactivity of the free and hidden antibodies to phospholipids. While free antibodies reacted preferentially with phosphotidylcholine, hidden antibodies reacted with cardiolipin and phosphotidylserine.

[Changes in the intensity of lipid peroxidation in the blood plasma of sheep under repeat gamma irradiation after chronic gamma exposure]. / Izmenenie intensivnosti perekisnogo okisleniia lipidov v plazme krovi ovets pri povtornom gamma-obluchenii posle khronicheskogo gamma-vozdeistviia.

The indices of lipid peroxidation and the contents of alpha-tocopherol and retinol in the blood plasma of sheep exposed to repeated gamma irradiations were studied. It was shown that a repeated acute gamma irradiation of sheep with sublethal and lethal doses after 9 months of chronic low-dose gamma irradiation adversely affected the activity of the lipid free-radical oxidation. A radiologic pathology in the repeatedly irradiated animals developed as a decrease in the intensity of spontaneous chemiluminescence. Also, a tendency to an increase in the concentration of malonic dialdehyde was observed along with weak changes in the contents of triene and diene conjugates and the levels of alpha-tocopherol and retinol.

[Increased plasma membrane permeability for Ca2+ in radiation-induced thymocyte apoptosis]. / Uvelichenie pronitsaemosti plazmaticheskoi membrany dlia Ca2+ pri radiatsionno-indutsirovannom apoptoze timotsitov.

Parameters of the Ca2+ permeability (the 45Ca influx rate in the presence of orthovanadate blocking the Ca(2+)-ATPhase, and the initial rate of the 45Ca uptake) and the DNA fragmentation were determined in rat thymocytes after gamma-irradiation-induced (with a dose of 5 Gy) apoptosis. Within the first 30-90 min after irradiation, the 45Ca influx rate that is characteristic of the membrane passive permeability remained unchanged. The initial rate of the 45Ca uptake that is characteristic of the Ca2+ exchange almost doubled. In 90-180 min, the rate of the 45Ca influx in the irradiated cells increased 1.5 to 2.0 times. An increase in the DNA fragmentation was observed in 90-120 min after irradiation of thymocytes; in 3 h, it developed up to 50%. Thus, modification of the membrane Ca2+ permeability in the irradiated thymocytes precedes a stage of initiation of the DNA degradation. A degree of disturbance of the membrane passive permeability increases as the thymocyte apoptosis progresses. The obtained data suggest that disturbance of the passive Ca2+ permeability and the intracellular Ca2+ homeostasis are responsible for the apoptosis of lethally irradiated thymocytes.

[Evaluation of hormonal status indicators and adenylate cyclase activity in animals in the follow-up of the Chernobyl AES accident]. / Otsenka pokazatelei gormonal'nogo statusa i aktivnosti adenilattsiklazy u zhivotnykh v otdalennye sroki posle avarii na Chernobyl'skoi AES.

Enhancing stimulation effect of prostaglandin E1 on adenylate cyclase, decrease in basal activity of adenylate cyclase in platelets and reducing thyroxine concentration in cow plasma 5 years after radioiodine damage to thyroid gland with doses higher than 200 Gy were detected, whereas only decrease in adenylate cyclase activity in platelets from animals irradiated with 40 Gy to thyroid gland was observed. No changes in platelet adenylate cyclase in cows exposed to less than 1 Gy to thyroid gland after 5 years of maintenance on the territory with 137Cs contamination density lower than 0.37 MBq/m2 were found.

[Total Ca contents in blood cells and plasma of the irradiated animals]. / Obshchee soderzhanie Ca v kletkakh krovi i plazme obluchennykh zhivotnykh.

It was found that the total Ca content in erythrocytes from irradiated sheep and horses increased by 10-40% from 1st till 5th days after irradiation, the intracellular Mg content being unchanged. More than 2-fold increase in total Ca content in lymphocytes during first 15 days was revealed, while in platelets only a trend for a growth in acute period of radiation disease was detected. On the contrary, no reliable changes in total Ca content in plasma after irradiation were observed. This fact indicates that Ca accumulation in blood cells after whole-body irradiation is due to disturbance in intracellular Ca(2+)-homeostasis.

[Modification of Ca2+ metabolism in the blood cells of cattle with radiation-induced thyroid disorder after the Chernobyl nuclear power plant accident]. / Modifikatsiia obmena Ca2+ v kletkakh krovi korov s radiatsionnym povrezhdeniem shchitovidnoi zhelezy posle avarii na Chernobylskoi AES.

Increasing of Ca2+ concentration in cytoplasm and of the rate of 45Ca iflux into cows erythrocytes in 19-24 month after Chernobyl accident was revealed. Correlation between Ca2+ concentration in cytoplasm of erythrocytes and thyroxin content in plasma of cows with radioiodine damage of thyroid gland was found. Reduction of the rate of 45Ga influx into erythrocytes in cows with radiation doses of 20-60 By on thyroid gland was shown in later time after accident (3-5 years). Changes in Ca2+ permeability through membranes of erythrocytes and neutrophils after injection of 131I into calves in doses of 300 Gy and more on thyroid gland was found.

[The effect of increased levels of chronic UVB-radiation on the functional state of the body in sheep]. / Vliianie povyshennykh urovnei UF-izlucheniia zony B na funktsional'noe sostoianie organizma ovets pri ego khronicheskom deistvii.

The effect of increased doses of UV-B-radiation produced by LER-40 lamps (with an intensity of 5.5 W/m2 at a daily dose of 20 kJ/m2 and a total dose for 15 days of 300 kJ/m2) on the cardiovascular function, biochemical, biophysical and structural parameters of blood plasma and cells of sheep was investigated. It was found that increased UV-B-radiation produced functional changes in different physiological systems of animals: arrhythmias, diastole shortening, increase of the systole-diastole index; decrease of platelet count, shortening of blood coagulation time; increase of calcium, iron and copper and decrease of zinc in plasma; conformational changes in cytoplasmic membranes of platelets and lymphocytes. The changes that occurred in the sheep at an early stage of exposure can be viewed as adaptive. However, functional changes that were seen at remote stages suggested that the sensitivity of various systems of the body to UV-B-radiation was different.

[Changes in the spontaneous DNA-synthesizing activity in the peripheral blood lymphocytes of irradiated animals]. / Izmenenie spontannoi DNK-sinteziruiushchei aktivnosti v limfotsitakh perifericheskoi krovi obluchennykh zhivotnykh.

In lymphocytes of sheep exposed to 52 and 103 mC/kg radiation revealed was an increase in spontaneous incorporation of 3H-thymidine into DNA. A change in spontaneous DNA-synthesizing activity in lymphocytes of exposed animals was accompanied by the increase in the total protein content of the peripheral blood lymphocytes.

[The content of immunoreactive calmodulin in the blood cells of irradiated animals]. / Soderzhanie immunoreaktivnogo kal'modulina v kletkakh krovi obluchennykh zhivotnykh.

The immunoreactive calmodulin content was shown to increase in the irradiated platelets of rats and cows. Total Ca content did not vary significantly in platelets of exposed animals although there was a tendency toward its increase. At the same time, total Ca content in lymphocytes of irradiated cows increased while the immunoreactive calmodulin level remained unchanged.

[Change in the adenylate cyclase activity of the lymphocytes and thrombocytes in irradiated sheep]. / Izmenenie aktivnosti adenilattsiklazy v limfotsitakh i trombotsitakh obluchennykh ovets.

Changes in basal and prostaglandin stimulated activity of adenylate cyclase in lymphocytes and platelets of irradiated sheep are phasic. In platelets adenylate cyclase activity is maximum on days 5 and 10 following irradiation, whereas in lymphocytes the enzyme activity is maximum on day 7. cAMP phosphodiesterase activity is slightly changed in platelets and increased in lymphocytes of exposed sheep.

[The treatment of acute cholecystitis]. / Lechenie ostrogo kholetsistita.

The authors treated 462 patients with acute cholecystitis. Operated on were 220 patients. Of them, 53.6%--at the first 24 hours after admission. In 26.3% of the patients, peritonitis was an indication for the operation. The postoperative lethality was 4.1%.