Use of porine fromYersinia pseudotuberculosis outer coat for serological diagnosis of pseudotuberculosis

Porine from the outer coat ofY. pseudotuberculosis is shown to be a species-specific agent of pseudotuberculosis. Porine-based enzyme immunoassay permits the detection of antibodies to all serological variants ofY. pseudotuberculosis. The possibility of diagnosing the disease in the early stages of infection is one advantage of the proposed method. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 199–202, August, 1995     

Damage to the internal organs of experimental animals infected with Marburg's virus

It is shown that in grivets and guinea pigs Marburg's virus reproduces in cells of the mononuclear phagocyte system, in hepatocytes, and in a few endotheliocytes. Marked pathological changes develop in the liver, spleen, and kidneys. A peculiarity of infection in monkeys is the entire absence of morphological manifestations of an inflammatory reaction and of immune system activation. Cells of the mononuclear phagocyte system are thought to play a crucial role in the development of pathological changes in the organism of infected monkeys and guinea pigs. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 430–434, April, 1994     

A study of nonpathogenicFrancisella,Brucella, andYersinia strains as producers of recombinant β-endorphin

Yersinia pseudotuberculosis, Brucella abortus, andFrancisella tularensis strains producing a recombinant β-endorphin have been obtained. The highest production of this peptide, which displays physiological activity, was recorded for cells of theY. pseudotuberculosis strain 2243 (pSK95E). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 612–615, June, 1994     

Cytoarchitectonics of the striate cortex in carnivores and primates following optic tract transection

Examination of brains from Old World monkeys and cats one year after optic tract transection showed a significantly reduced density of neurons in layer IV C of area 17 (striate cortex) in the projection of central vision on the transection side in the monkeys but not in the cats. It is concluded that peripheral vision is less vulnerable to deafferentation than central vision. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 95–96, July, 1994 Presented by O. S. Adrianov, Member of the Russian Academy of Medical Sciences     

Role of the interaction between different types of serotonin and α2-adrenergic receptors in the regulation of audiogenic seizures in DBA/2 micereceptors in the regulation of audiogenic seizures in DBA/2 mice

It is shown that the serotonin receptors 5-HT_1c, 5-HT₃, and 5-HT₄ and α₂-adrenergic receptors are involved in the regulation of audiogenic seizures in DBA/2 mice, and that the effects of these serotonin receptors on the duration and magnitude of convulsive activity are the opoosite of those produced by α₂-adrenergic receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 381–383, April, 1995     

Immuno- and phagocytosis-modulating properties of low doses of B1-aflatoxin and benzene

Benzene or benzene-dissolved B₁-aflatoxin in low doses promotes an increase of the Thy-1⁺ cell count in the bone marrow of mice and an enhancement of the thymusdependent immune response.In vitro aflatoxin and benzene are unable to induce the expression of Thy-1-antigen in bone marrow T-precursors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 158–160, February, 1994 Presented by S. A. Neifakh, Member of the Russian Academy of Medical Sciences     

Time course of the content of cellular elements in the peritoneal exudate of BALB/c mice infected with coxsackievirus A13

Coxsackievirus A13 is shown to suppress macrophage exudation into the peritoneal cavity of adult male BALB/c mice. The influence of the infection on the counts of lymphocytes and polymorphonuclear leukocytes is less expressed. The detected changes are regarded as a manifestation of the immunomodulating action of coxsackievirus A13 infection. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 75–77, July, 1995 Presented by V. P. Kaznacheev, Member of the Russian Academy of Medical Sciences     

Graphic analysis of contraction-distension isotherms for pulmonary surfactant monolayers

A new method for analyzing the surface-active properties of pulmonary surfactants is proposed, based on calculating a “local stability index” and then plotting this index as a function ofS/S _o, whereS _o andS are, respectively, the initial and contracted areas of the surfactant monolayer formed at the interface. The course of the curves thus obtained allows for reasonably precise and easy comparisons of alterations in the surface-active properties of pulmonary surfactants in response to different factors acting on the body. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp 370–372, October, 1995 Presented by B. I. Tkachenko, Member of the Russian Academy of Medical Sciences     

Synthesis and properties of the immunotoxin CD5-ricin

Synthesis and properties of an immunotoxin produced by conjugating ricin with a novel monoclonal antibody (IgG3 of the ICO-104 class) are described. Cytolytic activity of the synthesized immunotoxin, determined by two independent methods and expressed in LD₅₀, is 0.3–0.6×10⁻⁷ M. Its specificity for target cells containing the CD5 antigen is shown. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 76–79, January, 1995 (Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences)     

Enhancement of liver cell proliferation by GM3 ganglioside

In experiments on rats subjected to partial hepatectomy and experimentally induced hepatitis it is shown that GM₃ ganglioside of equine erythrocytes can enhance liver cell proliferation. The effect was also observed in experiments on a primary hepatocyte culturein vitro; moreover, enhancement of cell proliferation did not depend on the type of sialic acid residues. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp 427–430, April, 1995     

A method for monitoring toxic damage to the liver,based on measurement of total water and its magnetic relaxation characteristics

Acute poisoning of rats with the hepatotropic poison tetrachloromethane was accompanied by increases in the liver content of total water and its spin-lattice (T ₁) and spin-spin (T ₂) relaxation times and by a decrease in theT ₁/T ₂ ratio, with reversal of the correlation betweenT ₁ andT ₂. The antihypoxic agent sodium γ-oxybutyrate normalized water metabolism in the liver almost completely. It is concluded that total water content andT ₁ are the more informative parameters for monitoring both toxic liver damage and the efficacy of its pharmacological correction. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 584–586, December, 1995 Presented by Yu. A. Vladimirov, Member of the Russian Academy of Medical Sciences     

Protective effect of intracerebroventricular injection of adenosine agonists during total cerebral ischemia

Adenosine and its analogs N⁶-cyclohexyladenosine (CHA) and N-ethylcarboxamideadenosine (NECA) are highly effective when injected into the lateral ventricle in very low doses (by 1–2 orders lower than subcutaneously). The protective effect of A-agonists is considered to be mediated by a central mechanism and realized via A-receptors of the brain: the effects of low doses of A-agonists are mediated by A₁-receptors, whereas higher doses exert an extra A₂-effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 622–624, June, 1994 Presented by P. V. Sergeev, Member of the Russian Academy of Medical Sciences     

Effect of dexamethasone on the expression of binding sites for high-density lipoproteins in cultured rat hepatocytes (Independence of the hormone effect on the intracellular cholesterol pool)

It is shown that glucocorticoids play a key regulatory role directed toward the maintenance of an optimal level of binding and internalization of HDL₃ in hepatocytes. Their stimulatory effect on the expression of HDL receptors proves to be independent of changes in the CH content in parenchymal cells. Translated fromByulleten' Eksperimentalnoi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 50–53, January, 1994     

Assessment of the toxic and protective effects of initiators and inhibitors of free radical reactions using a wild-type strain ofEscherichia coli and a strain deficient for superoxide dismutase

The toxic effects of H₂O₂, paraquat, and oxidized low density lipoproteins are more expressed on superoxide dismutase-deficientE. coli strains than on its wild-type strains, and the effect of tert-butyl-hydroperoxide is less dependent on the presence or absence of this enzyme in the bacterium, whereas that of bleomycin does not depend on it at all. The toxicity of the agents increases in the following series: H₂O₂<oxidized low density lipoproteins<tert-butyl-hydroperoxide <paraquat≪bleomycin. A culture ofE. coli strains AB 1157 and JI 132 may be used for assessing the toxic effect of prooxidants, and anE. coli JI 132 culture with oxidative stress induced by prooxidants as a test system for detecting the potential antioxidants and assessing the mechanism of the action. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o , pp. 74–79, January, 1996 Presented by A. I. Archakov, Member of the Russian Academy of Medical Sciences     

Effect of a peptide extract of fetal brain tissue on the intracellular pH of mouse peritoneal phagocytes

The intracellular pH (pH_i) of mouse peritoneal neutrophils, initially 0.2 U, drops after a 15-min incubation of these cells with a peptide extract of fetal brain tissue. Treatment with the preparation leads to appreciable changes in the distribution of neutrophils by the examined parameter. For macrophages, the acidifying effect of the agent and its effect on the pattern of cell distribution in terms of pH values are far less expressed. The effects of the agent in dilutions 1∶10² and 1∶10⁴ on the mean pH_i are virtually the same. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 12, pp. 626–630, December, 1995 Presented by V. I. Kulakov, Member of the Russian Academy of Medical Sciences     

A study of the mechanism of action of befol on Ca2+ metabolism in cardiomyocytes using a FURA-2 fluorescent probe

The dynamics of the Ca-response of cardiomyocytes is studied and the efficiency of befol, verapamil, and amiodarone is compared using various experimental models of stimulation of [Ca²⁺]_i. Befol (1–5 μM) is shown to inhibit the caffeine-and strophanthin G-induced rise of [Ca²⁺]_i. Unlike verapamil and amiodarone, befol exhibits no Ca-blocking activity in modeled K-depolarization. It is concluded that the cardiotropic effect of befol is mediated through its primary action on Na⁺/Ca²⁺ exchange in cardiomyocytes, while the cardioplegic effect of verapamil and amiodarone is due to their ability to block the slow Ca²⁺ inward current. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 288–291, March, 1996     

Comparison of the blood level of endogenous paramagnetics in health and pathology using proton magnetic relaxation

An experimental study is made of the longitudinal proton relaxation timeT ₁ in human serum in health and pathology as a function of the protein concentration using partially lyophilized samples. A comparison of the results with those obtained with modeled aqueous protein solutions and extrapolation of the dependences to the zero concentration demonstrate that the concentration of paramagnetic admixtures is the same in groups of healthy subjects and patients with malignant neoplasms who have reliably differentT ₁ values in native samples. There is no difference in the longitudinal proton relaxation time of the nonaqueous component of the serum between these groups. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 11, pp. 557–560, November, 1995     

Delayed-type hypersensitivity and the pathogenesis of viral hemorrhagic fever (African swine fever)

A potent inhibition of leukocyte migration, as high as 98%, was observed in superacute and acute forms and exacerbation of the chronic form of African swine fever. In an asymptomatic infection the inhibition is no more than 30%. Inhibition of the migration of porcine leukocytes infected in a cell culture was 73 to 90% after infection with four virulent strains and 15 to 36% after infection with two attenuated strains. The data onin vitro andin vivo leukocyte sensitization in African swine fever are indicative of a correlation between the severity of the pathogenetic picture of the disease and the degree of delayed-type hypersensitivity. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 168–170, August, 1994 Presented by A. A. Vorob'ev, Member of the Russian Academy of Medical Sciences     

Changes in the ultrastructure of human erythrocytes and in their content of free fatty acids during incubation with hydroperoxide and calcium ionsin vitro

It is shown that incubation of a suspension of human erythrocytes with H₂O₂ and Ca²⁺ mainly results in echinocytic transformation and hemolysis; incubation with H₂O₂ in the absence of Ca²⁺ is attended by polymorphous changes in erythrocytes: discocyte swelling, formation of stomatocytes and echinocytes and their hemolysis. The level of free fatty acids in human erythrocytes increases for incubation with Ca²⁺ and calcimycin under anaerobic conditions and drops for H₂O₂-induced activation of lipid peroxidation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8 pp. 207–211, August, 1994 Presented by N. K. Permyakov, Member of the Russian Academy of Medical Sciences     

Effect of pH and glutathione on lipid peroxidation in tocopherol-enriched liposomes

Tocopherol-enriched liver microsomes are more resistant to lipid peroxidation at an alkaline pH of 8.5 in comparison with microsomes incubated at pH 7.5. An alkaline pH provides conditions for two-electron oxidation of tocopherol, which causes the lipid molecule to revert to the initial state (O₂/H exchange). A possible mechanism of inhibition of lipid peroxidation within the physiological range of pH with participation of a glutathione-dependent enzyme is discussed. Translated fromByullenten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 268–270, September, 1995 Presented by E. I. Chazov, Member of the Russian Academy of Medical Sciences