Xymedon restores T-cell immune response inhibited by γ-irradiationin vivo: Interrelations with Ca2+-ATPase and DNA-relaxing activities

High radioprotective activity of xymedon was shown in mice. Radioprotective effects of this preparation were accompanied by restoration of the delayed-type hypersensitivity response and Ca²⁺-ATPase activity in splenocytes which were inhibited by γ-irradiation (3 Gy). At concentrations of 10⁻³ and 10⁻⁶ M xymedon stimulated the activity of DNA topoisomerase-I of splenocyte nuclei. Here we discuss a mechanism of radioprotective effects of pyrimidine derivatives associated with the inhibition of apoptosis of lymphoid cells and the stimulation of proliferation and differentiation of lymphoid precursor cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 127, No. 1, pp. 66–70, January, 1999     

Modulation of interleukin-2-induced proliferation and nonspecific cytotoxicity of rat lymphocytes by phorbol myristate acetate and staurosporine

It is shown that a 19-h pretreatment of rat splenocytes with 1 μM phorbol 12-myristate 13-acetate followed by a 42-h incubation with human recombinant interleukin-2 inhibits nonspecific cytotoxicity of these cells toward the target YAC-1 cells. By contrast, proliferation of splenocytes and thymocytes incubated under the same conditons increases considerably. The inhibitor of protein kinase C staurosporine (0.1 μM) significantly decreases nonspecific cytotoxicity of splenocytes after a 20-min incubation, while in a dose of 0.01 μM it stimulates lytic activity of splenocytes and thymocytes following a 3-day incubation with interleukin-2 in the presence of the inhibitor. Cell proliferation under these conditions is markedly decreased. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 122, No. 10, pp. 394–398, October, 1996     

Contribution of the reproductive hormones to the regulation of prostaglandin F2α production by immunocompetent cells

The ability of estradiol, progesterone, and chorionic gonadotropin to influence prostaglandin F_2α production by intact splenocytes of CBA mice was studied. Estradiol and progesterone similarly activated the processes of prostaglandin F_2α production. No relationship was revealed between the effect and the concentration of the hormones. Chorionic gonadotropin activated prostaglandin production by immunocompetent cells but only when used in a concentration reflecting the peak of its physiological secretion. Combining gonadotropin with estradiol or progesterone did not lead to any appreciable differences in the prostaglandin-stimulating action of each hormone alone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 178–180, August, 1995 Presented by K. P. Kashkin, Member of the Russian Academy of Medical Sciences     

Derivation of a new B-cell line from mouse spleen and its characterization

Prolonged culturing of splenocytes of (CBA×C57B1/6)F₁ hybrid mice in RPMI-1640 medium with 15% fetal calf serum resulted in the derivation of a new B-cell line. After a monolayer of stromal fibroblast-like cells was formed, lymphoid cell growth was observed in 4–5 weeks of splenic cell culturing. All the cells of the splenic line belonged to the B series and expressed IgM on their surface; they did not form lymphoid colonies after injection to lethally irradiated mice, and even after 8-month culturing and several passages they could not be differentiated. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 183–186, February, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Lymphocytes from mice with a 1-methyl-4-phenyl-1,2, 3,6-tetrahydropyridine(MPTP)-induced parkinsonian syndrome reduce motor activity in C57Bl/6 mice

Motor activity of C57Bl/6 mice is found to be decreased following syngeneic transfer to them of splenocytes from mice with an MPTP-induced parkinsonian syndrome. The decrease in motor activity does not result from the transfer of MPTP and is apparently associated with the transfer of B lymphocytes and with antibody production by these cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 232–234, March, 1994     

Size of lymphocyte subpopulations in the spleen and level of hemopoietic tissue proliferation in mice during surgical interventions

The percent and absolute content of T helpers increases in the spleen of mice 4 and 17 h after resection of the liver or removal of a kidney, which is associated with an increase of the mitotic index of splenocytes. The number of T suppressors and the bone marrow cell mitotic index are unchanged. The T-helper/T-suppressor ratio in the spleen increases 1.7–2 times during surgery on the liver and kidney. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 301–303, March, 1996 Presented by N. K. Permyakov, Member of the Russian Academy of Medical Sciences     

Immunomodulating effect of weak magnetic fields on antibody production in mice

The possibility of a resonance mechanism of immunomodulation of antibody secretion by immune antibody-producing splenocytes in mice is demonstrated. Parameters of the effects of weak magnetic fields on the process of immune antibody production in mice are defined. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 482–483, May, 1994 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Modification of ethylmethane sulfonate-induced mytagenesis with adrenaline

Experiments withCrepis capillaris dry seeds show that pretreatment with adrenaline hydrochloride and adrenaline hydrotartrate significantly reduces the number of aberrations induced by the supermutagen ethylmethane sulfonate. The effective concentration ranges for adrenaline adrenaline hydrotartrate and hydrochloride are 10⁻¹–10⁻⁷ M and 10⁻³–10⁻⁷ M, respectively. Adrenaline hydrochloride is more effective than adrenaline hydrotartrate (79.1vs. 65%, respectively). Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 126, No. 10, pp. 427–429, October, 1998     

Modulation of the oxidative burst in mouse macrophages and human neutrophils by superlow concentrations of GM1 ganglioside

It is shown that ganglioside GM1 in picomolar concentrations stimulates the phorbol-12-myristate-13-acetate (PMA)-induced generation of active forms of oxygen by neutrophils and peritoneal macrophages. GM1 (10⁻¹¹ M) is found to enhance the luminol-dependent chemiluminescence induced by 10⁻⁸ M PMA in mouse macrophages in comparison with the effect of PMA alone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 44–46, January, 1994 Presented by A. N. Klimov, Member of the Russian Academy of Medical Sciences     

Detoxication of benzene and aflatoxin B1 with amino acid and peptide preparations in mice and chicken

Incubation of mouse and chicken splenocytes with amino acid or peptide preparationsin vitro increases cell resistance to benzene and aflatoxin B₁. Short-term (15 days) treatment of chicken with an amino acid mixture (aviamine) in combination with benzene also increased splenocyte resistance to toxinin vitro. By contrast, aviamine in combination with aflatoxin B₁ sharply decreased cell resistance to toxin. Glutamic acid possessed no such properties. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 10, pp. 419–421, October, 1999     

Non-invasive imaging of optical parameters of biological tissues

The normalised back-scattered intensity (NBI) profiles at various locations on the forearms of ten human subjects were obtained by moving the multi-probe of a laser reflectometer. The statistical analysis of the NBI data showed that the variation in the NBI was significantly higher at the ulnar region compared with that at other regions. For determination of the scattering (μ _s ) and absorption (μ _a ) coefficients and the anisotropy parameter g at each location on the forearm, these profiles were matched with the NBI profiles simulated by a Monte Carlo procedure (χ _0.99 ² ). For the reconstruction of images of variation of these parameters, the averaged values ofμ _a ,μ _s and g at all locations on the forearms of the subjects were determined. The absorption coefficient had a minimum (1.92 cm⁻¹) and maximum (2.21 cm⁻¹) at the wrist and the lateral region of the forearm, respectively. The scattering coefficient had a maximum (194 cm⁻¹) at the medial side and near the elbow, and a minimum (186 cm⁻¹) at the lateral side of the forearm. Similar changes in the anisotropy parameter were also observed. By interpolation of the data of each parameter on a 100×100 image matrix and after median filtering, colour-coded images of the variation in the optical parameters were constructed. These images could be useful for diagnostic and therapeutic applications of lasers.     

Antitumor activity of normal bone marrow cells

After separation of normal murine bone marrow cells in a Percoll density gradient cellular fractions with densities of 1.076 and 1.060 g/ml are capable of suppressing thein vitro growth of leukemia cells. The cytostatic activity of these fractions, however, does not surpass the level of antitumor antiproliferative activity intrinsic to intact bone marrow cells. These cells were found to be capable of joining the splenocytes, thymocytes, and lymph node cells in effector cytostatic cooperation and thus enhance the final antitumor effect. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 181–183, August, 1995     

Mechanism of heart-rate acceleration caused by stimulation of vagal centers in the frog

The mechanism by which heart rate is increased upon stimulation of vagal centers is studied using frog heart preparations perfused with Ringer—Locke solution containing atropine and/or benzohexonium. Atropine stimulates vagus-induced heart-rate acceleration in dilutions of 10⁻⁶ and 10⁻⁵ g/ml. In a dilution of 10⁻⁴ g/ml both atropine and benzohexonium abolish vagal tachycardia. Rausedyl (3–4 injections, 5 mg/kg, at 18–20-h interval) prevents tachycardia. Stimulation of both halves of the medulla oblongata increases heart rate to a greater extent than stimulation of one half. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 7, pp. 16–20, July, 1997     

Ultrastructural changes in albino mouse liver caused by isogenous F1+ and F1− strains ofYersinia pestis and their correction with ceftriaxone

Fatty dystrophy and partial cytoplasmic necrosis predominate during the preagonal period in parenchymatous organs of mice infected withYersinia pestis 231 F1⁺. Endothelial damage, fibrin precipitation, and microcirculatory disorders occur in sinusoidal capillaries. More pronounced changes in the liver develop during the preagonal period in mice infected withY. pestis 231 F1⁻. Treatment with ceftriaxone leads to 100% survival in both groups and substantial restoration of liver structure. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, No. 5, pp. 589–593, May, 1996     

Inhibition of mitogen-stimulated proliferation of human lymphocytesin vitro by synthetic peptide fragments of α-2 interferon

Human α-2 interferon and peptides representing parts of the amino-acid sequence 124–138 of the IF molecule inhibit the proliferative response of peripheral blood lymphocytes from healthy donorsin vitro induced by ConA. It is shown that neither interferon α-2 nor biologically active peptides change the level of interleukin-2 ConA-induced production by human blood mononuclears. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 72–74, January, 1994 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Effects of thymidine and phorbol 12-myristate 13-acetate on erythroid differentiation of K562 cells and their sensitivity to nonspecific lysis by rat splenocytes

Induction of hemoglobin synthesis in K562 cells by thymidine (2 mM)in vitro did not significantly enhance major histocompatibility complex antigen-unrestricted lysis of splenocyte-exposed K562 cells. Inhibition of thymidine-induced hemoglobin synthesis by simultaneous incubation of cells with thymidine and phorbol 12-myristate 13-acetate (100 nM) decreased cytolytic activity of splenocytes against K562 cells. Preincubation of tumor cells with phorbol ester alone did not affect major histocompatibility complex antigen-unrestricted lysis induced by rat splenocytes but decreased the basal level of hemoglobin synthesis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 128, No. 11, pp. 521–524, November, 1999     

Gastric mucosal lesions caused in rats of different strains by emotional stress,and the protective effect of interleukin 1β

Acute emotional stress results in damage to gastric mucous membranes in August, Wag, and particularly Wistar rats. The damage is less severe in rats preinjected with inter-leukin 1β into a lateral ventricle of the cerebrum. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 238–239, March, 1994     

Inhibition of platelet aggregation by monoclonal antibodies against glycoprotein IIb–IIIa complex

Monoclonal antibodies CRC64 are obtained against Ca²⁺-dependent glycoprotein IIb–IIIa complex of the platelet membrane which possess the ability to inhibit completely fibrinogen-dependent platelet aggregation. CRC64 is directed against the epitope formed by the glycoprotein IIb–IIIa complex and does not interact with proteins isolated after platelets are treated with ethylenediamine tetraacetate. Complete, reproducible blockade of platelet aggregation caused by 5 μM adenosine diphosphate is noted in an MCA concentration of 3 μg/ml, while in the case of a stronger inductor, namely 1 U/ml thrombin, platelet aggregation is inhibited in a concentration of 5 μg/ml. F(ab′)₂ fragments are also able to inhibit platelet aggregation completely and are usually effective in concentrations lower than native monoclonal antibodies. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 10, pp. 402–405, October, 1994 Presented by V. N. Smirnov, Member of the Russian Academy of Medical Sciences     

Effect of ultralow doses of thyroliberin on microviscosity of lipid components of biological membranes

Effects of the regulatory peptide thyroliberin on microviscosity of lipid components of endoplasmic reticulum biological membranes in mouse hepatocytes were studied by electron paramagnetic resonance. Thyroliberin in a concentration of 10⁻³–10⁻¹⁸ M decreased microviscosity of surface layers of membrane lipids. This decrease was the most pronounced (30%) under effects of 10⁻¹⁰ and 10⁻¹⁶ M thyroliberin. Physiological effects of thyroliberin corresponded to its influence on the membrane structure. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 1, pp. 38–40, January, 2000     

Stimulation of proliferative activity of human natural killers (CD16+CD56+ cells) by recombinant interleukin-3in vitro

The proliferative activity of human natural killers (CD16⁺CD56⁺ cells) in the presence of 100 and 1000 IU/ml human recombinant interleukin-3 is investigatedin vitro. It is shown that recombinant interleukin-3 reliably enhances natural killer proliferation, causing a 9–15.2-fold increase of³H-thymidine uptake by CD16⁺CD56⁺ cells both in complete culture medium and in conditioned medium. The effect of the factor is 3.9–6.4 and 3.6–8.9-fold more potent than that of recombinant interleukin-2 and granulocyte-macrophage colony-stimulating factor, respectively, in the same doses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 409–412, April, 1995 Presented by S. V. Prozorovskii, Member of the Russian Academy of Medical Sciences