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The experimental study identified the antiviral activity of Bacillus pumilus RNase (binase) against the reovirus of serotype 1/strain Lang. For the first time, it has been found that 50 μg/mL of binase effectively reduced the hemagglutinin and cytocidal activity of reovirus in Vero cell line. The preincubation of the enzyme with reovirus before infection of the cells inhibited the viral replication. To determine the stagedependent effect of reovirus reproduction upon binase inhibition, the infected cells were treated with binase or RNase A at different phases of the infectious cycle. The treatment of virus-infected cells has revealed that both enzymes have a maximal antiviral effect on the reovirus propagation during early phases of the reovirus reproduction cycle, with binase being more effective than RNase A. It has been hypothesized that the combined action of the oncolytic reovirus and binase is promising for the elimination of tumor cells carrying mutated RAS gene.

By the method of indirect immunohistochemistry, distribution of transferrin and of transferrin receptor of the type (TFR1) was studied in the formed rat eye retina at the period of early postnatal ontogenesis (from birth to opening of eyelids). It has been established that the character of distribution of these proteins and intensity of specific staining change dependent on the retina formation stage. Retina of the newborn rat is characterized by diffuse transferrin distribution in nuclear retina layers (in the neuroblast layer--NBL) and in the ganglionic cell layer (GCL) as well as in the eye pigment epithelium (PE); relative immunoreactivity to transferrin is not high. At the 5th postnatal day, immunoreactivity to transferrin is maximal and is revealed both in nuclear and in plexiform layers of retina and in the eye PE, the greatest signal being characteristic of NBL. At the 10th postnatal day the transferrin signal intensity in retina decreases, specific staining is revealed in GCL, PE, and in the area of formed outer segments of photoreceptors. At the 15th postnatal day, transferrin is revealed in GCL, in outer and inner photoreceptor segments and in the eye PE. TFR1 is present in all retinal layers at all stages of the retina formation; the relative immunoreactivity to TFR1 sharply rises beginning from the 10th postnatal day; correlation between distribution of transferrin and TFR1 is detected in the entire retina of newborn rats as well as in the external retina area at subsequent stages of its development. A possible role of transferrin at various stages of formation of retinal is discussed.

Study of behavior and performance patterns of two Bion 11 monkeys showed that they adapted to the space environment at a different rate. Inflight, both animals successfully performed eye-head-hand coordination tasks (Program 1) and failed to complete foot pedal tasks (Program 2), although they were successful in performing Program 2 before and immediately after flight.

Before flight, the flight pool monkeys were trained to experience spaceflight-type effects (diminished motor activity and confinement) and to perform eye-head-hand coordination and foot-pedal tasks. A battery of tests was used to select strong and highly adaptable animals as flight candidates. The animals with strong active defensive and exploratory reactions proved to be the best.

Measurement of non-heme iron in the sera of patients with peripheral tapetoretinal abiotrophy aged 10-72 years with stages I-IV of the disease showed a statistically significant (26-30%) decrease of this parameter in comparison with healthy controls. Total iron-binding capacity of the serum was unchanged. The results are discussed with regard for previous reports about changed iron homeostasis in animals with hereditary retinal degeneration (Campbell rats) and the role of iron in the development and formation of nervous tissues.

Ribosomes, sufficiently purified by physicochemical criteria (with the RNA/protein ratio equal to 1.6 - 1.7), were isolated from disintegrated C.perfringens cells, type A, strain BP6K, by ultracentrifugation or by fractionation with polyethylene glycol. The purified conjugates of ribosomes and C.perfringens toxoid, absorbed on aluminum hydroxide, were obtained. The ribosomal preparations had low toxicity and high protective activity: when used in a dose of 6 binding units, they protected guinea pigs and mice inoculated with 8 - 9 LD50 of C.perfringens culture.

Effects of ferric ions, native ferric chelator desferal and of microsomal membranes containing different amount of nonheme ferric on activity of aldose reductase were studied in the enzyme preparations isolated from brain cortex and sometimes from retina of healthy rats and of the animals with hereditary degeneration of retina. In the healthy animals activity of aldose reductase was distinctly increased in the presence of ferric ions and of microsomal membranes; desferal inhibited drastically the enzyme activity. At the same time, these agents did not affect the aldose reductase activity in the preparations isolated from the animals with hereditary degeneration of retina.

Maximal activity of NADP.H-cytochrome c reductase was found in the liver, the lowest one--in the retina. On the contrary, the highest activity of aldose reductase was observed in the retina, the lowest one--in the liver. The activity of NADP.H-cytochrome c reductase in the retina of rats with hereditary degeneration of the retina increased to the 60th day of postnatal life by 33%, the increase reaching 273% to the 90th day. In the brain cortex, the increase in the activity to the 45-60th days amounted to 22-34%, whereas at the age of 90 days the difference between healthy and patient rats, as well as the difference between males and females became less significant. The activity of aldose reductase in the cortex and retina in patient rats at the 20th day was 35% lower than in healthy animals. In the liver of patient rats, to the age of 45 days, the activity of aldose reductase decreased by 38%. At other periods, no significant differences were observed between healthy and patient animals with respect to the activity of this enzyme.

It is established that previously observed increased rate of the induced lipid peroxidation in brain tissue of rats with hereditary retinal degeneration as compared with normal rats is due to the change of the rate of this process in the microsome cortex brain fraction and was not observed in the mitochondrial-synaptosomal and nuclear fractions. The content of nonheme iron ions in microsome cortex brain fraction of the Campbell rats is decreased by 35% and of the Fe ion was in the reduced form as compared with the Wistar rats. The ratio of Fe2+/Fe3+ in this fraction of the Campbell rats will be 5.21; Wistar rats--0.51. The increase of the reduced form of the Fe ion may be a result of the increased rate of the glucose-6-phosphate dehydrogenase activity in cortex brain tissue of the Campbell rats. We accept change of the content and the forms of the Fe ions in the microsome cortex brain fraction as a cause of the increased rate of induced lipid peroxidation in brain of the Campbell rats. All the observed phenomena are manifested at the early stage of life and indicated that different metabolic disorders can be observed in the Campbell rats not only in the retina and eye pigment epithelium but also in the brain tissue.

In relation to Cosmos experiments behavioural responses of rhesus monkeys were investigated and compared with their conditioned reflex activities. The animals with a distinct search-oriented behaviour showed a higher rate of recovery of instrumented reflexes, better stability of conditioned-reflex activities to stress-effects and a faster adaptation to them. Extreme effects associated with changes in the experimental environment and rigid fixation inhibited conditioned-reflex activities to a greater extent than strong but short-term exposures followed by tests in a normal environment. It was also demonstrated that variations of the sleep structure in stress situations were largely dependent on typological features of animals.

The data on the study of the protective activity of theta hemolysin and Cl. perfringens lecithinase preparations and the corresponding antitoxic sera obtained by indirect immune affinity chromatography are presented. Experiments in mice and guinea pigs indicate that the injection of antihemolytic serum and immunization with anatheta hemolysin ensures the protection of the animals from theta toxin. The enrichment of analecithinase preparation with anatheta hemolysin has been found to increase its protective properties against Cl. perfringens culture and toxin.

Purified Cl. perfringens theta-hemolysin with a specific activity of 15-16 X 10(5) HU per mg of protein nitrogen, toxic for mice when injected intravenously, has been obtained by precipitation with zinc chloride, gel filtration through Sephadex G-100 and ion-exchange chromatography on DEAE Sephadex A-50. 1 Dcl of the toxin is 0.2-0.4 mg. The yield of theta-hemolysin amounting to 20-25% has been achieved, the degree of its purification reaching 80- to 120-fold. Equine anti-theta hemolytic serum has been obtained. The method for the determination of the anti-theta toxin-binding properties of Cl. perfringens toxins and the quantitative content of anti-theta-hemolysin in sera has been developed.

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