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2161. [Hematopoietic stem cell count in mice with stimulated and suppressed erythropoiesis. I. Blood loss and acute hypoxia].
Polypotential hemopoietic stem cell numbers were determined by means of the splenic colony-forming unit (CFU-S) method in bone marrow and spleen of CBA mice in different periods after bleeding and acute hypoxia. After these treatments, radioactive isotope (59Fe) uptake by erythroid cells, considered as an index of erythropoietic activity, enhanced in the spleen, but in the bone marrow it either diminished (after acute hypoxia), or remained unchanged (after bleeding). Bleeding caused a considerable increase in the splenic CFU-S numbers, but the bone marrow CFU-S contents were unchanged. It was found that splenic CFU-S number decreased on the 1st and 4th days after acute hypoxia, but increased on the 7th day; bone marrow CFU-s numbers increased on the 7th day. Possible mechanisms involved in the hemopoietic stem cell perturbation in the hemopoietic organs after the erythropoiesis stimulating treatment are discussed.
2162. [Role of surface H-2 antigens in regulation of hematopoietic stem cell proliferation].2163. [Age-related changes in the hemopoietic microenvironment].2164. [Genetic resistance to hemopoietic cells in the cellular lympholysis reaction].2165. [Stromal bone marrow cells and the hematopoietic microenvironment].
Stromal clonogenic fibroblasts of the bone marrow possessing osteogenic potential are responsible for hemopoietic bone marrow microenvironment. These cells may be recovered from the bone marrow by cloning in cell cultures; their progeny cells upon retransplantation into the body form new bone marrow organs. Microenvironmental cells are histogenetically independent of hemopoietic cells. In bone marrow cell suspensions prepared by bone marrow tissues trypsinization stromal clonogenic cells are present in greater concentrations than in those prepared by mechanical mincing of the bone marrow tissue. New ectopic bone marrow organs may be created by transplantation of trypsinized suspensions in porous sponges.
2166. [Effect of bone marrow hyper- and hypoplasia on the process of body distribution of granulocytic-macrophagal hematopoietic stem cells].2169. [Correlations of the geometric and electrophysiologic characteristics of brain stem neurons in the kitten].
Spike activity of the medially and laterally localized units was compared in the pontomedullar reticular nuclei on 1-5 and 15-30 day old kittens. The amplitudes of spikes, spontaneous and evoked patterns of firing in the lateral and medial groups were different. The ratio of cells responding to single and high-frequency stimuli was lower in the lateral units and higher in the medial ones. The medial units had a more significant background firing activation in the interstimulus intervals. It is supposed that the medial cells reflect the properties of densely ramified giant neurons and the lateral--those of the sparsely ramified units. The difference between their electrophysiological properties may be connected with the dendrite geometry, especially with maximal branching foci of dendrites.
2170. [Properties of the hamatopoietic cells in mice with chromosome 19 trisomy].
作者: A P Dyban.;N G Khrushchov.;S I Polikarpova.;E I Domaratskaia.
来源: Dokl Akad Nauk SSSR. 1982年263卷2期454-6页 2171. [Effect of DNA on recovery of the hematopoiesis in mice with myelosan-induced hypoplasia].
作者: V M Luzanov.;S A Rogacheva.;L B Shagalov.;Iu P Vaĭnberg.
来源: Biull Eksp Biol Med. 1982年93卷1期84-7页
CBA male mice received myelosan intraperitoneally in a dose of 10 mg/kg weekly for 5 weeks. One day after the second myelosan injection, the animals were given high-molecular DNA once a week for 9 weeks. DNA preparations were obtained from the milt of sturgeon fish. Heterologous DNA was shown to change the rate of hypoplasia development during myelosan administration and to affect the completeness of hemopoiesis recovery during discontinuation of cytostatic injections. This was determined by the action of the biopolymer on the colony-forming units and on differentiated myelokaryocytes. The action of DNA on hemopoiesis in mice with cytostatic hypoplasia affected the animals' survival. In the course of the observation period, the death in the group of untreated mice constituted 68%, while that in the group of treated animals to 20%.
2172. [Selective toxicity of dimethyl sulfoxide for the hematopoietic cells of human embryonic liver].2173. [Recovery of locally irradiated areas of bone marrow in mice and rats by virtue of stem cell migration into these areas].2174. [Dynamics of rat bone marrow CFUc during prolonged fractionated irradiation].2175. [Radiosensitizing action of 8-bromoadenine on hematopoietic stem cells in mouse bone marrow].2178. [Hematopoietic stroma and the regulation of hematopoiesis in extramedullary bone marrow transplants in mice].
The bone marrow fragments were transplanted under the renal capsule and "stromal function" of the transplants during up to 1.5 years was estimated by the numbers of CFU-S, myelokaryocytes and the weight of newly formed bone tissue. On the basis of the published and authors' data, a conclusion was drawn that the ability of the stromal precursor cells of bone marrow to provide for the growth of hemopoietic territories is limited by the size of medullary cavity; outside its limits this ability is not only realized, but may be additionally stimulated by some distant factors (preirradiation of the recipients in the given case). The self-maintenance ability of the stromal mechanocytes from the old mice during 43 months was shown by means of retransplantation. On the basis of electron microscopy and published data, a suggestion was put forward that fibroblastic reticular cells might be ancestral elements of osteogenic differentiation.
2179. [Donor-origin CFU-S in long-term functioning extramedullary bone marrow transplants in mice].2180. [Role of atypical sex cells in the histogenesis of germinative testicular tumors].
Histochemical and electron microscopic study of 23 germinative tumors of the testicle and organ tissue beyond the tumor was carried out. In 78% of the observations, normal seminiferous tubules were found to contain a special kind of cell elements, atypical sex cells (ASC), not observed in health. Ultrastructural and histochemical features of undifferentiated cells comprising seminoma and embryonal cancer were found to be similar to those of ASC and gonocytes of human embryo. The results suggest that ASC are the stem tumor cells for human germinative neoplasia which are characterized by single cytohistogenesis.
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