[Different mechanisms of blood thymidine levels caused by irradiation and polyanion administration]. / Razlichnye mekhanizmy timidinemii, vyzvannoi oblucheniem i vvedeniem polianionov.

The administration of dextran sulfate causes an increase in the thymidine content of rat blood comparable with the postirradiation thymidinemia. In contrast to radiation dextran sulfate does not increase polydeoxynucleotide content of thymus. Isoptin, a calcium antagonist, decreases thymidinemia induced by dextran sulfate to a greater extent than that induced by ionizing radiation. Thymidinemia induced by dextran sulfate is supposed to be due to its effect on cell membranes. In radiation-induced thymidineamia this mechanism is of lesser significance.

[Free thymidine in the blood serum of irradiated rats with different levels of cellular depletion of the thymus and spleen]. / Svobodnyi timidin v syvorotke krovi obluchennykh krys pri raznykh urovniakh kletochnogo opustosheniia timusa i selezenki.

The levels of the postirradiation thymidinemia, with an equal degree of the proceeding cell depletion of lymphoid organ tissues caused by the administration of dexamethasone and exposure of rats to 3 Gy radiation, markedly varied. Three days after the injection of the hormone, the organism responded to irradiation by an increase in the concentration of thymidine in blood serum in the same manner as intact animals did. The preirradiation with a dose of 3 Gy reduced sharply the ability of the organism to respond the repeated irradiation (after 3 days) by thymidinemia. There was a lesser increase in the thymidine concentration in the blood after the injection of dexamethasone than after irradiation inducing the same cell depletion of the thymus and spleen.

[A simple radioimmunological method of determining thymidine in biological fluids]. / Prostoi radioimmunologicheskii metod opredeleniia timidina v biologicheskikh zhidkostiakh.

A simple, sensitive and reproducible radioimmunoassay for determination of thymidine in biological fluids was developed. The technique is based on competition between 3H-thymidine and unlabelled thymidine for antithymidine antibodies. The cross-reactivity of structurally related compounds with the antibody was mostly negligible, except for deoxyuridine. The sensitivity of the assay was 10(-7) M. This radioimmunoassay may be used for measuring content of thymidine in blood serum and urine. A method for direct determination of thymidine in urine was not described before.

Antibodies to natural double-stranded RNA and to synthetic polyribonucleotides in the sera of patients with systemic lupus erythematosus.

A parallel testing of antibodies to double-stranded ribonucleic acid in 80 sera from patients with systemic lupus erythematosus by the membrane binding method using natural 3H-dsRNA preparation and synthetic 125I-poly I. poly C preparation revealed a good correlation (r = +0.81). In a selected set of patients with SLE we observed a slight tendency to preferential binding of the natural preparation and a lower frequency of anti-dsRNA antibodies when compared to that reported by other investigators. The presence of anti-dsRNA did not correlate with the presence of anti-dsDNA.

[Factors affecting the DNA-binding activity of the blood serum in in patients and healthy persons at low ionic strength]. / Faktory, vliiaiushchie na DNK-sviazyvaiushchuiu aktivnost' syvorotki krovi bol'nykh i zdorovykh liudei v usloviiakh nizkoi ionnoi sily.

Interaction of blood serum proteins with native DNA at low ionic strength [0.05 M NaCl and 0.015 M sodium citrate], estimated by adsorption of DNA-protein complex on nitrocellulose filtrs, depended on specific activity, molecular weight of DNA as well as on the amount of DNA and blood serum in the samples. DNA-binding activity of blood serum from the patients should be estimated at such ratio of components, when the blood serum from healthy persons adsorbed minimal quantities of DNA, since the molecular weight and specific activity of the DNA preparations might vary in various samples. As a factor, regulating the rate of DNA binding on filtrs, such amount of blood serum from patients should be added to the samples, which corresponded to the maximal amount of normal blood serum causing no binding with the DNA preparations.

[Antibodies to double-helical RNA and several viruses in medical personnel caring for systemic lupus erythematosus patients]. / Antitela k dvuspiral'noi RNK i nekotorym virusam u meditsinskogo personala, obsluzhivaiushchego bol'nykh sistemnoi krasnoi volchankoi.

An average level of antibody to double-stranded RNA in patients with systemic lupus erythematosus and medical staff taking care of these patients is higher than that in physicians from other institutions and donors. The level of antibodies to antigens of various viruses in lupus patients is elevated in comparison with that in the medical staff. No statistically significant differences in the levels of antibody to viruses in the staff of various institutions were found.

[Increased thymidine excretion under the influence of polyanions]. / Povyshennaia ékskretsiia timidina pod vliianiem polianionov

During the first 24 hours following injection of polyanions (dextran sulphate in a dose of 62.5 mg per 1 kg of body weight; poly I. poly C in a dose of 2.5 mg per 1 kg of body weight) to rats and mongrel albino mice an increased urinary excretion of thymidine was revealed which occurred after their exposure to high X-ray doses. An increase in urinary excretion of thymidine is assumed to be due to migration of lymphocytes to the blood channel.