The paper is concerned with some experimental data of a comparative study of the efficacy of a hypoxic mixture used for the protection of hemopoietic tissue in single and fractionated irradiation of animals. The protective effect was shown to be on the decrease in change from acute to fractionated irradiation during hypoxia. The use of two criteria of assessment (specific for the hemopoietic system--CFU-C and integral--50% the survival rate among animals 50%) confirmed the general direction of processes. Hypoxia used as a protector, resulted in a decrease in an effective irradiation dose, manifested in lesser affection of the hemopoietic stem cell pool and consequently in the proliferating bone marrow cell pool.

The influence of a tumor-necrotic factor (TNF) on the CFUs population has been studied normally and after irradiation. An inhibitory effect on the pool of the seven-day and doubling of the yield of the eleven-day colonies have been observed in mice received TNF 20 h before bone marrow removal as compared with the controls. The kinetics of restoration of bone marrow cellularity and CFUs number in mouse donors treated with TNF 20 h before irradiation (5.0 Gy) has demonstrated the stimulatory effect of the agent on both indices.

Dynamics of recovery of humoral immunity of CBA mice was studied 1, 3, 6 and 12 months after termination of long-term exposure to tritium oxide at various levels of absorbed doses (3, 5 and 9 Gy) and dose rates (3.3, 4.9 and 9.2 cGy.day-1). A severer and more stable residual radiation damage was observed in the department of lymphocyte precursors. A considerable decrease in the content of antibody producers was due to the lymphoid tissue hypoplasia. There was a direct relationship between the immunodeficiency and dose rate and total absorbed dose of beta radiation.

Afferent projections to the functionally identified bulbar locomotor region which is situated in the medial reticular formation were studied in cats and rats by means of horse-radish peroxidase technique. Cells of origin of such projections were found not only in hypothalamic and mesencephalic locomotor regions but also in the interstitial nucleus of Cajal and adjacent structures and in the ventral part of the caudate nucleus.

The role of intercellular interactions in regulation of proliferation process in normal and tumor cells has been studied in experiments with mouse hybrids F1 (CBA X C57BL/6). The cytostatic activity to tumor cells has been shown to possess both adherent and nonadherent cells of bone marrow. The adherent cell-effectors inhibit, nonadherent ones stimulate the DNA synthesis in myelokaryocytes of normal bone marrow. During the activation of bone-marrow proliferation (under 10-hour immobilized stress) the cytostatic effect of nonadherent cells to tumor ones grows; the myelokaryocyte proliferation is stimulated on the 4th day after immobilized stress. The cytostatic activity of adherent cell-effectors remains to be low up to 7th day after immobilization. The maximum of depression in cytostatic function of the adherent elements coincides with the peak of bone marrow proliferation activity (6th day). The character of changes in cytostatic activity of adherent cells to tumor and nontumor ones is of the same type. The data obtained testify to the generality of regulation mechanisms in proliferation of tumor and normal cells.

We studied distribution of mRNA for nuclear protooncogene c-myc and nuclear protein P-53 in mature oocytes and embryos of Xenopus laevis from the stage of fertilization up to the stage of hatching by in situ hybridization with histological sections. mRNA for c-myc was present in all cells of the embryo at all studied developmental stages. Between the stage of fertilization and up to the late blastula, mRNA concentration for c-myc decreased progressively in all embryonic cells. During gastrulation a local increase in the concentration of this messenger was found in dorsal mesoderm and ectoderm. At the stage of neurula increased concentration of mRNA for c-myc was observed in all cells of the embryo but the hybridization signal increased particularly distinctly in cells of the neural tube. In studies of P-53 mRNA distribution hybridization signal was detected only in brain cells after stage 20 of development (after closure of the neural folds) and up to the stage of hatching.

Anti-horseradish peroxidase IgG (a-HRP) secreting hybridoma lymphoblasts grown subcutaneously in recipient mice have been studied light and electron microscopically 30-120 min following capitation of the animals. Conventional HRP-DAB immunocytochemical staining was performed for demonstration of a-HRP which in the living cells was restricted to the rough endoplasmic reticulum, the perinuclear cisterns, the Golgi apparatus and some microvesicles. 30 min after death in a number of the cells a-HRP began to invade the cytosol leaving, however, the nucleus and mitochondrial matrix free of the secretory marker. 30 to 90 min later staining intensity became similar in all cellular structures thereby making an impression of overall a-HRP spreading throughout the cell. In the light of these findings and the data obtained by other investigators a conclusion is made on the diffusion of macromolecules across intracellular membranes as a result of considerable post-mortem disturbances in membrane permeability.

It is a review of works concerning the new mechanism of immunoregulation by immature erythroid cells (Er-suppressors). Er-suppressors producing humoral activity were shown to be capable of inhibiting B cell proliferation, production of immunoglobulins and humoral immune response both in mice and man. By certain characteristics Er-suppressors seem to be an logous to natural suppressors described by many authors. It is common knowledge that natural suppressors play a substantial role in the regulation of early stages of lymphocytopoiesis. Erythropoiesis disturbances may lead to the appearance at the periphery of immature precursors from bone marrow and to the suppression of B cell proliferation in the peripheral blood and lymph nodes. Detection of Er-suppressors in the patients' peripheral blood by immunofluorescence with monoclonal antibodies allows one to study their role in autoimmune and lymphoproliferative diseases and secondary immune deficiencies and to elaborate new methods of the diagnosis and treatment of these diseases.

Erythropoiesis and immunity are evaluated in (C57BL/6xDBA/2) F1 mice with immune complex glomerulonephritis induced by GVHR as compared to the genetically determined models of systemic lupus erythematosus. Elevated content of serum blood antinuclear antibodies, polyclonal activation during early disease periods, immune complex deposition in kidney tissues indicate the presence of the autoimmune syndrome in (C57BL/6xDBA/2)F1 mice, similar to that in mice with genetic lupus nephritis. The findings of a decrease of CFUs on days 5 and 8 at early times of disease, a reduction of hematocrit in combination with the enhancement of stem cell proliferation on the 6th-7th month of disease, an increase of the absolute leukocyte count and relative monocyte count in the peripheral blood of diseased mice may attest to the depression of stem cell differentiation in erythropoiesis and to the enhancement of stem cell differentiation in granulocyto-monocytopoiesis, that needs, however, further research and confirmation.

The radioprotective and restorative (therapeutic) effects of human recombinant interleukin-1 beta (IL-1 beta) on the population of bone marrow CFU-S of mice, subjected to either sublethal doses of ionising irradiation itself or the same irradiation in combination with thermal burn, are investigated. Both the effects of the agent are registered under both in vitro and in vivo irradiation in semi-, syn- and allogeneic animals. If the irradiation was combined with thermal burn, the "therapeutic" effect of the agent was demonstrated at irradiation dose equal to 3.06 Gy rather than to 6.12 Gy. If the bone marrow cells were irradiated in vitro in dose 3.06 Gy with the following heat shock at 42 degrees C for 10-20 min, the "therapeutic" effect of IL-1 beta was seen only if it was added to cells before rather than after irradiation. The radioprotective effect of IL-1 beta is maintained under in vitro, as well as in vivo conditions in the allogeneic system of transplantation of the CBA donor bone marrow to the C57BL mice.

As many as 120 neurosurgical patients were examined after the excision of hemispheric gliomas, basal and subtentorial tumors. Based on an the computer-aided analysis biochemical and clinical data, attempts have been made to unify the mechanisms responsible for brain edema development in patients with neurosurgical pathology. In the early postoperative period, brain edema occurs in 95% of neurosurgical patients. Edema development, spreading and intensity depend on the site and nature of the primary pathological focus as well as on traumatism of surgical interventions. It is proved that edema is an original, biologically expedient brain response to its injury. This response manifests in hyperhydration of all tissues, with the maximum intensity being concentrated in the focus of injury. Specific (neurogenic neurohumoral) and nonspecific (biochemical, autoimmune, mechanical, and so forth) factors of brain edema development may be distinguished. The differences in the neurogenic and neurohumoral mechanisms by which brain edema develops may be accounted for by the topography of the focus of injury. The closer the pathological focus is to the stem and diencephalic structures, the more remarkable the action of neurogenous and neurohumoral factors and the more distinct the tendency toward edema generalization are. At the diencephalic level of injury, damaged are the structures responsible for central regulation of metabolism and trophicity of nerve cells. The neurogenously precipitated diffuse impairment of permeability of the cells entails their hyperhydration, which marks cellular (cytotoxic) edema. The subtentorial process that affects the vasomotor centre of the stem triggers the neurogenic diffuse alterations in the vascular tone, manifesting in an increase of permeability for water and plasma proteins which is characteristic of vasogenic edema.(ABSTRACT TRUNCATED AT 250 WORDS)

It has been established that bone marrow stroma integrally participates in acute lymphoblastic leukemia (ALL) reparation in children. The regularities of changes in its function were revealed over time and during remissions as was the sensitivity to polychemotherapy carried out during ALL remission. Studies into the function of stromal precursors of fibroblasts provide important information for estimation of hemopoiesis in children undergoing ALL remission.

Three subpopulations of Golgi-stained neurons of the brainstem reticular nuclei have been studied by the method of computer morphometry in 30-day old kittens. 23 parameter of the neuronal geometry were analyzed after uni-and bilateral lingual nerve section 5-7 days after birth. All of cells display statistically valid changes in some parameters, typically differing in every group: for reticular neurons--free distribution of dendrite endings in the dendritic field; for arborescent ones--the length of dendritic segments; for giant multipolar neurons--distribution of foci of maximal dendrite branching in the dendritic field. Unilateral lingual nerve section gives more pronounced quantitative deviations from the normal state, than bilateral one.

Ontogenetic differentiation of the lung was shown to be subject to determination, divergence and cell differentiation. Delay in determination was followed by proliferation of stem and precursor cells resulting in various types of dysplasia. Disorders of tissue divergence were observed during differentiation whereas various degree of cell differentiation disturbances was registered in moderately and poorly differentiated tumors.

An attempt was made to characterize the development of neurones of sensory trigeminal nuclei--basic structure of sensory provision of alimentary behaviour at late stages of postnatal ontogenesis. The method of the brain-stem slices of rat pups [correction of ratlings] aged 2.4 and 8 weeks was applied. An increase with the age was shown of the number of neurones with spontaneous activity (44%-2 weeks; 69%-8 weeks), growth of discharges frequency, appearance of cells population with high-frequency spontaneous activity by the fourth week and an increase of such neurones number by the eighth week. Three types of background-active neurones were singled out: episodic, continuous and group; the dynamics of correlations change of these types with the age was shown. No significant changes of rest potential with the age were found, though there was a tendency to its increase between the 2-nd and 8-th weeks of postnatal development.

Examination of 80 patients with ischemic and hemorrhagic brain strokes has revealed definite phasic alterations that occur in osmotic homeostasis and hemorheology. In the acute disease period, the intensity of the hyperosmolar syndrome is dependent on the levels of hyperglycemia, azotemia, hypernatremia and is provoked by the impairment of the central and peripheral mechanisms of regulation of water-electrolyte metabolism and osmotic homeostasis as a result of the direct effect of the pathological focus or secondary impairment of the brain stem due to brain edema associated with dislocation of the median and stem structures. That the disease exhibits in the presence of progressively increasing hyperosmia, the decreased parameters of hemolysis coupled with a gradual decline of the aggregation capacity of platelets and red blood cells, blood viscosity, with the high fibrinogen indicators being preserved, points to the failure of the functional potentialities of blood cell elements. The data obtained can serve as a prognostic criterion for the disease outcome and efficacy of infusion and dehydration therapy.

The colony-forming activity of embryo lung cells CBA mice was determined according to the Till and McCulloch technique (1961). After intravenous injection to jung cells (1 x 10(6)) from 14-day embryos the total number of colonies on the area of 1 mm2 of spleen sections from irradiated recipient mice averaged 2.31 +/- 0.39 whereas after transplantation of lung cells from 15-day embryos it averaged 2.34 +/- 0.53. The percent of macrocolonies equalled 52.5% in the former case and only 2.5% in the latter case. Macrocolonies contained cells of the myeloid, erythroid and megakaryocyte lines. Microcolonies predominantly consisted of granulocytes at various stages of differentiation. Thus, polypotent stem hematopoietic cells migrate into the fetal lung in vivo. The colony-forming ability of the lung polypotent stem cells decreases as the period of embryogenesis increases.

The influence of cystamine delivered in a radioprotective dose before and after irradiation of mouse-recipients (8 Gy) on the effectiveness of exogenous bone marrow cloning has been investigated. Cystamine administered prior to irradiation exerts a protective effect on CFUs and also causes an increase in the number of splenic colonies grown from CFUs of the transplanted bone marrow. With cystamine administered after irradiation the protective effect is absent, but the CFUs number in the femur increases in recipients transplanted with intact bone marrow in comparison with those transplanted without cystamine. It is believed, that in addition to the specific protective mechanism of action of radioprotectors, there is a nonspecific mechanism of increasing the proliferation of protected stem cells that is connected with the stimulatory effect of radioprotective agents on the haemopoietic stroma elements.

The ability of lymphocytes to inhibit proliferation of non-syngeneic stem cells decreases differently after exposure in vivo and in vitro. The causes of the observed differences and the mechanism of radiation impairment of this function under different irradiation conditions have been investigated. Cells exposed in vivo die in the interphase irreversibly. The newly formed lymphocytes start the repair process as late as one month after irradiation. The injury to in vivo exposed cells is severer due to the presence of oxygen in tissues. A definite time interval is needed for the damaging effect of oxygen radicals to be implemented: the effect is maximum as early as 4 h following irradiation. With in vivo exposure under hypoxic conditions the functional activity of lymphocytes is the same as that of lymphocytes irradiated in vitro with the same dose. In vitro irradiation of lymphocytes at a high oxygen content causes a decrease in the functional activity of cells.