The Mechanism of the Stimforte Effect on the Activation of Target Cell Defense against Viral Infection.

Stimforte in a wide range of concentrations (15-225 µg/mL) totally inhibits the cytopathic activity of hepatitis C virus (HCV) in the Vero-V cell culture. Interferons (IFN) play the most important role in the suppression of infection when the drug is introduced into the culture before the infection. When Stimforte is introduced after the infection, the mechanism of action seems to be different. The activators of IFN production are mainly (or exclusively) the ligands of receptor complexes TLR-4 and NOD-2 contained in the drug. The action of these substances is probably synergistic, similar to the action of LPS and MDP in Vero-V cells.

[Substances from pyrolised tissues of reptile carcases differently modulate immunity of mammals of both sexes].

Substances with gender action on immunity were detected in water soluble hydrolised matter from reptile carcases. The gender action was shown on isolated blood neutrophils, whole blood and in vivo by the antiviral activity on experimental animals, contaminated with three types of viruses: Herpes simplex type 1, the virus of encephalomyocarditis and the virus of hepatitis of mice. The possible mechanism of the inhibitory action on the male immunity was associated with the protein kinase cascade, including protein kinase C, activated by phorbolmyristate in the cells of the immune system.

[Stimforte action on the main inflammation characteristics in experimental animals contaminated by Herpes simplex-1].

In the brain and lungs of the experimental animals contaminated by Herpes simplex-1 there were detected much higher levels of the thiobarbituric acid-stained lipid oxidation products and proteolytic activity, evident of the inflammation process. Stimforte lowered the inflammation indices to the level, close to that in the brain of the noninfected animals. Yet the drug provided lower titers of the virus in the brain, lungs and serum in the contaminated animals and arrested the infection process by stimulation of the immune system. The mechanism of the inflammation suppression is discussed.

[Effect of Stimforte in combination with Virazole on infection induced by hepatitis C virus in mice].

Twenty-four hours after intramuscular injection of Stimforte in a dose of 25 microg in mice weighing 18-20 g, chronically infected with hepatitis C virus (HCV), viral infection was shown to be at the most suppressed viral replication, as suggested by the data of the infectious and antigenic activities of HCV. Following 72 hours of its administration, the quantity of viral antigen and the infectious activity restored. Readministration of the agent considerably suppressed HCV replication. When given in a dose of 12.5 microg/kg, the agent reduced HCV titers by 2.0-2.5 log10 TCID50; when used in a dose of 25 microg/kg, it diminished the infectious activity of HCV by 3.2 log. The similar data were obtained in the study of the antigenic activity of HCV in infected animals. The effect of Virazole in combination with Stimforte in reducing the replication of infectious HCV and the accumulation of antigens in HCV-infected mice was additive or synergic, suggesting that it is expedient to use them concurrently.

[Effect of Stimforte on infection induced by hepatitis C virus, genotype 1b].

When given at two concentrations of 12.5 and 25 microg/kg to mice weighing 18-20 g in chronic Infection, the novel immunomodulator Stimforte was tested for effects on replication of hepatitis C virus (HCV), 1b strain. The efficacy of the agent was evaluated from the decrease in virus titers in the liver, serum, brain, and spleen and from the reduction of antigen titers in the same organs. When administered at a concentration of 12.5 microg/kg, the agent was ineffective and did not decrease significantly the examined indices in any of the organs. When used at a concentration of 25 microg/kg, Stimforte significantly lowered the number of virus antigen in the study organs, rather than in the serum, the liver showing a 15-fold antigen reduction as compared with the controls. HCV replication decreased by 2.4 log10 in the serum and 1.7-1.9 log10 in the organs of the animals given the agent. A Stimforte-induced decrease in HCV replication correlated well with the increased concentration of proinflammatory cytokines (tumor necrosis factor-alpha, interferon-gamma, interleukin (IL)-6, IL-1 beta , which might be one of the mechanisms responsible for the antiviral activity of the agent in hepatitis C.

[Change in Na+,K+-ATPase activity during reproduction of the tick-borne encephalitis virus in SPEV cell culture]. / Izmenenie aktivnosti Na+,K+-ATPasy pri reproduktsii virusa kleshchevogo éntsefalita v kul'ture kletok SPEV.

Changes in the activity of Na(+),K(+)-ATPase during infection of SPEV cells with tick-borne encephalitis (TBE) virus were studied in preparations of cell membranes and directly in the culture and the effect of this enzyme activity on the penetration of TBE virus in the cells and production of virus-specific proteins investigated. The highest activity of the enzyme was observed directly after challenge and during the 5th and 6th hours of infection, whereas the lowest was recorded during the second and third hours and 24 h postinfection. A similar decrease in the activity of this ATPase was observed in the brain cells of infected mice. Ouabain and low (0 degree C) temperature prevented the virus penetration in the cells, which indicates that this process is energy-dependent. Inhibition of Na(+),K(+)-ATPase led to a drop in the production of virus-specific protein.

[The use of rocket immunoelectrophoresis for determining glycoprotein in concentrated rabies vaccines]. / Primenenie raketnogo immunoélektroforeza dlia opredeleniia glikoproteina v kontsentrirovannykh antirabicheskikh vaktsinakh.

Rocket immunoelectrophoresis (RIE) was shown to be useful for the evaluation of glycoprotein (GP) content in concentrated rabies vaccines, and disintegron B., a zwitterionic detergent made in this country, for treatment of the vaccines for these evaluations. The values of GP content obtained by RIE and single radial immunodiffusion test were similar. The highest values were obtained for all the vaccines tested with anti-PM GP serum compared with anti-ERA and Vnukovo-32 GP serum. When anti-PM and anti-Vnukovo-32 GP sera were used for RIE two components were revealed in the vaccines. All the preparations under study contained soluble GP.

[Protein kinase activity of proteins extracted by triton X-100 from isolated rat liver cell nuclei and Zajdela hepatoma]. / Proteinkinaznaia aktivnost' belkov, ékstragiruemykh tritonom X-100 iz izolirovannykh kletochnykh iader pecheni krysy i gepatomy Zaidela.

Proteins extracted with Triton X-100 from rat liver tissue and Zajdela hepatoma nuclei exhibited similar electrophoretic properties of both proteins and phosphoproteins if they were separated by means of electrofocusing. Four protein-kinase activity peaks were detected in each of these preparations. Three protein-kinases from rat liver tissue and Zajdela hepatoma were similar in their electrofocusing point and substrate specificity. However, the fourth protein-kinase, which had pI 6.1-6.3 and was activated by rabbit muscle thermostable proteins, was detected only in the preparation of rat liver tissue, while the enzyme with isoelectric point at pH 4.0 was found only in Zajdela hepatoma preparation. All the protein-kinases studied phosphorylated nuclear matrix proteins at higher rate as compared with histones.

[Action of dithiothreitol on protein pattern and phosphorylation in nuclear matrix preparations isolated from the rat liver and Zajdela's hepatoma]. / Vliianie ditiotreitola pri vydelenii preparatov iadernogo matriksa iz pecheni krysy i gepatomy Zaidala na ikh belkovyi sostav i fosforilirovanie.

After rat liver nuclei had been treated with 10 mM dithiothreitol nuclear matrix contained 40 per cent less protein than without treatment. Protein composition did not change qualitatively. The protein with a molecular weight of 35 kD was not phosphorylated in the treated samples. After Zajdela hepatoma nuclei had been treated in the same way, nuclear-matrix contained 25% less protein. High molecular weight proteins (140, 150 and 220 kD) were solubilized by media containing dithiothreitol. After dithiothreitol treatment phosphatase and protein-phosphatase activities reduced dramatically both in rat liver and Zajdela hepatoma nuclear matrices.

[Proteolytic degradation of nuclear matrix proteins in the rat liver, Zajdela's hepatoma and hepatoma 22A in the presence of ATP]. / Proteoliticheskii raspad belkov iadernogo matriksa pecheni krysy, gepatomy Zaidela i gepatomy 22A v prisutstvii ATF.

An intense proteolytic degradation of both proteins and phosphoproteins has been observed in isolated nuclear matrices from rat liver, Zajdela Hepatoma and Hepatoma 22a, incubated with NP-40, DTT and gamma-[32P] ATP being most intense in Hepatoma 22a. Practically all phosphoproteins of Hepatoma 22a nuclear matrix degraded. This implies either an extremely high proteolytic activity in the preparation or the presence of a specific to phosphoproteins protease absent from rat liver and Zajdela Hepatoma nuclear matrices.

[Changes in biological properties of tick-borne encephalitis virus during cleavage of disulfide bonds in protein E]. / Izmeneniia biologicheskikh svoistv virusa kleshchevogo éntsefalita pri razryve disul'fidnykh sviazei v belke E.

The study showed the disruption of disulphide bonds in E protein of tick-borne encephalitis virus (TBE) to lead to the loss of antigenicity, infectivity, hemagglutinating and protective activities. The loss of infectivity under the effect of a thiolic reagent appears to be associated with block of the very first stage of virus-cell interaction, virus adsorption on the target cell. An attempt to reestablish the E protein structure and the above-mentioned virus properties after the removal of the thiolic reagent failed. The role of tertiary structure of E protein in the manifestation of TBE virus main biological properties is discussed.

[Comparison of the specificity of polyclonal antibodies to the tick-borne encephalitis virus in immunoenzyme analysis and immunoblotting]. / Sravnenie spetsifichnosti poliklonal'nykh antitel k virusu kleshchevogo éntsefalita v immunofermentnom analize i immunoblottinge.

The present study deals with the optimization of the conditions of immunoblotting (IB) and the enzyme-linked immunosorbent assay (ELISA) with the use of mouse polyclonal immunoglobulins to tick-borne encephalitis virus. In contrast to ELISA, the results of IB depended, to a great extent, on the composition and pH of blocking buffer mixtures. In some cases IB permitted the detection of a heretofore unknown virus-specific polypeptide with a molecular weight of 58-60 KD. The results of the study lead to the conclusion on the impossibility of the direct transfer of data concerning the specificity of individual preparations of immunoglobulins in ELISA or IB due to differences in information.

[Use of direct solid-phase immunoenzyme analysis for assessing the immunological activity of a vaccine against tick-borne encephalitis]. / Primenenie priamogo tverdofaznogo immunofermentnogo analiza dlia otsenki immunologicheskoi aktivnosti vaktsiny protiv kleshchevogo éntsefalita.

A high correlation between the current index of the effectiveness of tick-borne encephalitis vaccine, its protective activity in mice, and the results of the direct solid-phase enzyme-immunoassay has been established, which permits the use of this assay as an auxiliary method for the immunological evaluation of newly prepared commercial purified tick-borne-encephalitis vaccine.

[Phosphorylation of the nuclear matrix proteins of the liver and of Zajdela's hepatoma in the rat]. / Fosforilirovanie belkov iadernogo matriksa pecheni i gepatomy Zaidelia krysy.

The rate of protein phosphorylation in isolated nuclear matrices from liver and Zajdela's hepatoma is very high, being even slightly higher than in isolated nuclei. This indicates that active protein kinases remain tightly bound to the nuclear matrix, since the areas of phosphorylation are the same. However, during isolation of the nuclear matrix from labeled nuclei in the absence of proteolysis and dephosphorylation inhibitors, most part of the label is eliminated from nuclear matrix proteins. These proteins were phosphorylated in both the tissues, however, in Zajdela's hepatoma, two proteins with a molecular weight of 29-31 kD and four proteins with a molecular weight of 12-19 kD were phosphorylated more intensely than in the liver.

Toxins of some marine algae (Pyrrophyta).

The literature data on toxins of neuroparalytic action, produced by pyrrophytic algae and capable of being accumulated by edible mollusks, are presented. The LD50 for mice of saxitoxin, the best known and most strongly acting toxin, is 5-10 microgram/kg. some toxins of dinoflagellates have been isolated in purified form. Their physicochemical properties have been studied and the structural formula of crystalline derivatives of saxitoxin has been established. The major problem of environmental protection is associated with a study of toxic dinoflagellates.