Prophylactic and corrective action of the polyethylene oxide polyox WSR-301 in rats with experimental lipoidosis

Two once-weekly intravenous injections of the polyethylene oxide Polyox WSR-301 (yielding a blood concentration of the order of 5×10⁻⁶ g/ml) led to a 38% decrease in the area occupied by sudanophilic lesions in the aortic arch of rats fed an atherogenic diet for two weeks. Perfusion under constant pressure of the formalin-fixed vascular system in the posterior part of the body with physiological saline and then with polyethylene oxide (10⁻⁵ g/ml) was without effect in normal rats and in those with mild lipoidosis, but reduced hydrodynamic vascular resistance by 9–14.5% in rats with pronounced lipoidosis. Intravenous injection of polyethylene oxide into anesthetized rats with pronounced lipoidosis in doses that were subthreshold for normal rats (blood concentrations of the polymer were of the order of 10⁻⁷ g/ml) caused a 20% decrease in the total peripheral resistance to blood flow, with a 17–20% rise of the blood flow rate in the carotid artery. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 587–589, June, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Ambiguity of the effect of high and low doses of amino-acid preparations on the immune response and phagocytosis in mice

It is shown that the effect of amino-acid preparations (levamine-70–70, cerebrolysin, and aviamine) is dose-dependent. Thus, levamine-70 and cerebrolysin at 65 mg/kg do not affect the immune response but stimulate phagocytosis. Aviamine at 65 mg/kg inhibits the immune response but stimulates phagocytosis and in a dose of 6.5×10⁻² mg/kg boosts both processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 500–501, May, 1994 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

High-molecular-weight polyethylene oxide improves blood flow through stenosed carotid artery

Intravenous injection of 0.1 mg/kg high-molecular-weight polyethylene oxide (molecular weight 5.8×10⁶) to narcotized cats with experimental stenosis of the right carotid artery considerably improved blood flow and reduce blood pressure in stenosed vessel. This normalizes cerebral blood supply via both carotid arteries despite a decrease in systemic blood pressure. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 7, pp. 60–62, July, 1998     

Effects of dose and administration mode of endothelin 1 on the mean arterial pressure and heart rate in awake rats

The effects of bolus administration and short-term infusion of endothelin 1 in four doses (2×10⁻¹⁶, 2×10⁻¹⁴, 2×10⁻¹², and 2×10⁻¹⁰ mol/kg) on arterial pressure and heart rate were compared in awake rats. Infusion and bolus administration of the two highest doses increased arterial pressure and provoked bradycardia. Infusion of the two lowest doses increased heart rate without concomitant changes in arterial pressure, while bolus injection of endothelin 1 in the same doses decreased both arterial pressure and the heart rate. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 11, pp. 491–494, November, 1997     

Effect of hyperbaria on acetylcholinesterase of human erythrocytes

It is shown that a helium pressure of 100 kgs/cm² (9.81 MPa) inhibits acetylcholinesterase of erythrocytes within nonsaturation concentrations of the substrate and has no effect within saturation conditions. This effect is assumed to be one of the possible mechanisms of biological action of hyperbaria. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 10, pp. 399–401, October, 1994 Presented by Yu. A. Romanov, Member of the Russian Academy of Medical Sciences     

Effect of toxic substances of diphtheria corynebacteria on aggregation of human platelets

The effect of the toxic substances of diphtheria corynebacteria (diphtheria toxin, diphtheria anatoxin, and codivac) on the aggregation of human plateletsin vitro was demonstrated using platelet-rich plasma prepared from citrated blood and the standard platelet activator ADP (2×10⁻⁵ M). These substances induce platelet aggregation in a dose-dependent manner. Incubation of diphtheria toxin and anatoxin with platelets reduces ADP-induced and total platelet aggregation, the effect being dependent on the inducer dose and incubation time. By contrast, codivac stimulates ADP-induced and total platelet aggregation in all experimental series. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp 623–625, December, 1994 Presented by V. I. Pokrovskii, Member of the Russian Academy of Medical Sciences     

Effects of the nootropics piracetam and GVS-111 on voltage-dependent ion channels of neuronal membranes

The effect of two nootropics, piracetam and N-phenylacetyl-L-prolyglycine ethyl ester (GVS-111), is studied by measuring high-threshold K⁺ and Ca²⁺ currents in isolated snail neurons using a two-microelectrode patch-clamp technique. Piracetam and GVS-111 are shown to reduce the amplitude of both the K⁺ and the Ca²⁺ (to a lesser extent) current. The threshold concentrations for GVS-111 and piracetam are 10⁻⁹-10⁻⁸ M and 1–5×10⁻⁴ M, respectively. It is assumed that the antiamnestic effect of the nootropics is partially mediated by a blockade of ion channels of the neuronal membrane. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 151–155, February, 1996 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effect of human defensins on the cytoplasmic Ca2+ content in platelets

The effect of the total fraction of human defensins (HNP-1, HNP-2, and HNP-3) on the cytoplasmic Ca²⁺ content ([Ca²⁺]_i) in the platelets of healthy donors was studied. At concentrations of 0.1–40 μg/ml and an incubation time of 10 min defensins have no effect on [Ca²⁺]_i in platelets labeled with Fura-2AM. However, at higher concentrations (100 μg/ml) they increased platelet [Ca²⁺]_i. In addition, defensins (40 μg/ml) inhibited the Ca²⁺ increase in platelets induced by thrombin, adenosine diphosphate, and the lipopolysaccharide ofS. typhimurium endotoxin. The most pronounced inhibitory effect was observed in a suspension of thrombin-stimulated platelets. It is shown that the effect of human defensins on the functional activity of platelets is due to the alterations in the intracellular Ca²⁺. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 600–603, December, 1994     

Effect of endothelin-1 on DNA synthesis in tracheal epithelium and smooth muscle cells in newborn albino rats

Repeated (5-fold) intraperitoneal injections of 5×10⁻⁹ mol/kg endothelin-1 inhibited DNA synthesis in tracheal epitheliocytes and activated lipid peroxidation in the lungs of newborn rats. Endothelin-1 in a dose of 5×10⁻⁸ mol/kg stimulated proliferative activity of tracheal smooth muscle cells and intensified lipid peroxidation in the blood, which aggravated observed changes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 3, pp. 294–296, March. 2000     

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)     

Changed count of CD4+ T-lymphocytes in the bone marrow of aggressive CBA mice

Enhanced immune response of aggressive CBA mice after 10 daily confrontations in sensory contact on day 4 after immunization with sheep red blood cells (5×10⁸) is paralleled by an increase in the count of CD4⁺ T-cells in the bone marrow. Aggressive behavior, weight of the spleen, and count of CD4⁺ T-helpers in the bone marrow (which is increased only in aggressors with a history of at least 3 victories) are correlated. The effect of aggressive behavior on immunity can be caused by changes of the neurochemical status of the brain and determined by an increase in the CD4⁺ T-helper count. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 11, pp. 544–546, November, 1997     

Informational capacity of the rat sensorimotor cortex in the postresuscitation period (morphometric analysis of a neuronal population)

The number of neurons was counted in different functional neuronal complexes of the sensorimotor cortex in albino rats in the control and at different times after clinical death caused by asphyxia. A decrease of the number of neurons from 2.5×10⁶ in the control to 1.56×10⁶ toward the 30th day of the postresuscitation period was found in the sensorimotor cortex. The complexes of small neurons in the upper floor (layers II–IV) suffer badly, while the neurons of layer VI are damaged to a somewhat lesser degree and the cells of layer V are minimally altered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 331–333, March, 1995 Presented by L. V. Poluektov, Member of the Russian Academy of Medical Sciences     

Impact of 13(S)-HPODE,a lipoxygenase product of linoleic acid,on calcium transport and Na,K-ATPase activity in the myocardial sarcolemma

In thisin vitro study using a purified sarcolemmic fraction of guinea pig myocardium, the 13(S)-hydroperoxide of linoleic acid (13-HPODE) increased in a dose-dependent manner the permeability of myocardial sarcolemma to Ca ions in concentrations above 10 μmol/liter, stimulated Na/Ca exchange there in concentrations from 0.1 to 10 μmol/liter, and exerted a digitalis-like action on sarcolemmic Na,K-ATPase in concentrations between 0.1 and 100 μmol/liter (IC₅₀=20 μmol/liter). The results indicate that the linoleic acid hydroperoxide may be an effective modulator of sarcolemmic Ca²⁺ transport and of membrane-bound enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 255–257, September, 1995 Presented by D. F. Chebotarev, Member of the Russian Academy of Medical Sciences     

Microwave-induced changes in synaptoarchitectonics at different levels of the visual analyzer

It is shown that interneuronal bonds at different levels of the visual analyzer are highly sensitive to microwaves (60 mW/cm², 10 min). Evidence of this is seen from the early degeneration and reduced numerical density of synapses and, in the cortical substance, in the reduced total length of active zones of contacts. The rate of recovery of the synaptic apparatus decreases in the following order: retina→external geniculate bodies→visual cortex. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 219–222, February, 1996 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Impact of plasmin and its complexes with α2-macroglobulin or α2-antiplasmin on the proliferative activity of human lymphocyteson the proliferative activity of human lymphocytes

It is shown that plasmin in doses of 0.1, 1, or 10 μg/ml did not influence significantly phytohemagglutinin-induced proliferation of mononuclear lymphocytes in a 3-day culture with these cells. Their proliferative response to pokeweed mitogen was stimulated by plasmin in the dose of 10 μg/ml only. Biogenic complexes of plasmin with α₂-macroglobulin or α₂-antiplasmin induced a moderate reduction of spontaneous proliferation after 3 days of culture, and so did plasmin after 5 days; α₂-macroglobulin induced a dose-dependent comitogenic effect with phytohemagglutinin and pokeweed mitogen, while α₂-antiplasmin induced a dose-independent comitogenic effect with pokeweed mitogen. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 304–305, September, 1994 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences     

Effect of exogenous acetylcholine on neuromuscular transmission in the stimulated rat diaphragm

Nerve stimulation is performed in rat phrenicodiaphragmal preparations with armine-inhibited acetylcholinesterase. Acetylcholine (1×10⁻⁷ M) is added to the saline for 15 min, and as it is washed off (during 1–2 h), the amplitude of isometric contractions and of the total action potential increases in the continuously stimulated muscle. Contractions in response to direct muscle stimulation remain unchanged. The membrane resting potential of muscle fibers exposed to acetylcholine shifts by 2–3 mV toward hyperpolarization and remains at this level for 2 h after the removal of acetylcholine from the saline. Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 457–459, November, 1994     

The effect of some botanical preparations on the production of lymphocyte-activating factor by mouse macrophages after rotation stress

It is found that a short-term rotation stress triggers the production of lymphocyte-activating factors by peritoneal macrophages of (CBA×C57BI/6), F₁ mice and raises blood levels of interleukin-1α and corticosterone. Botanical preparations administered to unstressed animals induce no secretion of lymphocyte-activating factors by macrophages and do not change blood levels of interleukin-1α and corticosterone. The herbals limit the stress-induced production of lymphocyte-activating factors by peritoneal macrophages. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 135–138, February, 1996 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

An enzyme immunoassay system for neonatal screening for predisposition to allergy

A test system has been developed for rapid, simple, and reliable measurement of immunoglobulin E in umbilical blood in the range from 0 to 10 IU/ml with a sensitivity of 0.1 IU/ml. The system may be used for the detection of a predisposition to allergy at a very early age, allowing for timely measures to prevent allergic diseases. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 418–421, October, 1995 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Function of neutrophils in nonphlogogenetic reaction

Clinically nonphlogogenetic phagocyte reaction under conditions of bacterial challenge was studiedin vivo. The “mission” of phagocytes under such conditions is completed by evacuation of phagocytized bacteria from the site of capture into the blood and then into the intestine. The purulent process induced by massive doses ofStaphylococcus aureus (25×10⁶ and 25×10⁸ bacteria), without any concomitant injury to the peritoneum does not lead to the development of inflammation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 9, pp. 356–360, September, 1997     

Mechanism of arterial pressure elevation in calcium deficiency

We compared the effects of intravenous administration of the calcium-dependent hypertensive factor from the plasma of patients with essential hypertension and of a synthetic heptapeptide with hypertensive activity. Both substances prove to induce prolonged and pronounced elevation of arterial blood pressure. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 476–477, May, 1994 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences