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2181. [Proliferative potential of hematopoietic stem cells].2182. [Reaction between syngeneic hematopoietic stem cells and lymphocytes in leukemic AKR mice].
The syngeneic donor-recipient model was used to examine the influence of T lymphocytes from AKR mice with spontaneous leukemia on colony-formation and differentiation of hemopoietic stem cells. It was shown that in the stage of the neoplastic process development, the cells of lymph nodes and the thymus inhibited the colony-forming capacity in all the three hemopoietic lines (erythroid, myeloid, megakaryocytic) of the syngeneic normal and autologous bone marrow. In the late stages of leukemia aggravated by generalized infection, T lymphocytes stimulated the exo- and endogenous growth of the granuloid colonies, changing the erythroid-myeloid index to 1:1-1:2.7.
2183. [Stem cell inactivation by allogenic lymphocytes: characteristics of suppressor cells blocking the killer action of syngeneic lymphocytes].
The role of different T lymphocyte subpopulations in the process of allogeneic haemopoietic stem cell inactivation has been studied. The T lymphocyte subpopulations were fractionated in vivo using the homing properties (to the spleen and lymph nodes) plus sensitivity for ALS in vivo (recirculation properties), for thymectomy, for anti-Thy 1 serum in vitro and some others. The results obtained indicate that not only the killer lymphocytes, that provide stem cell inactivation, but also the suppressor cells, that provide inhibition of inactivation, take part in the reaction for allogeneic stem cells. Killer and suppressor cells differ alternatively in some physiological properties and may be separated for further studying.
2184. [Nucleic acid and protein content of cells of the raphe nuclei of the rat brain when the animals are deprived of the paradoxical sleep phase].
A 24 hours paradoxical sleep deprivation (PSD) with rats resulted in lowering the RNA content in neurons and gliocytes of n. raphé dorsalis by 31 and 18%, resp.; the protein content remaining unchanged. A 48 hours PSD reduced RNA and protein contents in neurons by 31%; in gliocytes both these substances being on the control level. In the neurons of n. raphé pontis, by the end of the 1st day of PSD the contents of both RNA and protein were seen reduced by 16 and 28%, resp.; however, by the end of the 2nd day their levels well compared with those in the control rats. There was a phase oscillation of protein content in gliocytes: from - 19%, on the first day of PSD, to +19%, on the 2nd day. There is a great resemblance in response to PSD between the adrenergic nucleus - locus coeruleus - and n. raphé pontis, whereas their responses differ from that of the serotoninergic n. raphé dorsalis.
2185. [Changes in the nucleic acid content of rat embryos incubated in vitro as affected by 17-beta-estradiol].2186. [Interaction of myeloid cells with stromal fibroblasts in monolayer cultures].
Stromal fibroblasts of bone marrow, spleen and thymus origin as well as fibroblasts of peritoneal fluid origin are shown to have no difference in the ability to bind morphologically distinguishable granuloid cells in monolayer cultures. On the contrary, thymus fibroblast colonies encourage the development of myeloid cell plaques (which are formed by bone marrow hemopoietic precursor cells) a great deal stronger than do bone marrow and peritoneal fluid fibroblast colonies. It means that their different origin may be revealed when they interact with hemopoietic precursor cells but not with differentiated myeloid cells.
2187. [Regulatory role of the bone marrow in the immune reaction].2188. [Concentration of nucleic acids and proteins in neurons and gliocytes of rat raphe nuclei following total sleep deprivation in a cylindrical treadmill].
RNA and protein contents in glial and neuronal cells of nucleus raphé dorsalis (NRD) increased by 23 and 31%, resp., following the 24-hr sleep deprivation; within 48 hrs the RNA content attained the normal level, the protein content being lower than normal by 21%. In neurons of nucleus raphé pontis (NRP) the macromolecules contents per cell remained unaltered at the first period of the sleep deprivation and elevated by 30% by the end of the second period. Metabolic changes in gliocytes were parallel to this. The findings suggest exhaustion of functional abilities of the NRD neurons in sleep deprivation as opposed to the NRP neurons.
2189. [Proliferative activity of differentiated bone marrow cells in children with aplastic anemia].2190. [Changes in the concentration of hematopoietic stem cells, erythrocytes and leukocytes during hepatoma development and in exposure to an antitumor agent].2191. [Immunodepressive properties of antineoplastic agents].
Experiments on CBA mice immunized with sheep red blood cells have shown that paphencyl, promycil, prospidin and imidazole-4-carboxamide decrease the number of IgM-antibody-forming cells in mouse spleens during the primary immune response. The highest immunodepressant effect was exhibited by paphencyl, while the least by prospidin. The maximum inhibition of the immune response was observed on paphencyl and promycil administration 24 hours after the immunization, that on prospidin administration 24 hours prior to antigen exposure, and that on imidazole-4-carboxamide administration 24 hours prior and 48 hours after the antigenic stimulation. The degree of antibody genesis suppression depends on the dose of paphencyl, promycil and prospidin and does not depend on the dose of imidazole-4-carboxamide. Paphencyl significantly diminishes the number of hemopoietic stem cells in mouse spleens, while prospidin was less active in this respect.
2192. [Use of DNA antibodies for detecting DNA radiation injuries in the bone marrow cell nuclei of irradiated animals].
Impairments in DNA from brain stem cell nuclei of X-ray irradiated animals were studied at early steps after irradiation using antibodies to single-stranded DNA. A possibility was shown to detect by means of an immunochemical technique the irradiation-induced impairments of DNA in brain stem cells. Detection of the impairment was possible within 3 hrs after high doses of the irradiation (206.4-258 mCi/kg); after lower doses - within the first hour of the postirradiation period. The immunochemical procedure might be used for early biological detection of the irradiation impairments as well as for estimation of radio-sensitivity of nuclear cells to the effects of irradiation and radioprotectors.
2193. [Effect of bone marrow trypsinization on the efficiency of fibroblast colony formation in monolayer cultures].
Stromal bone marrow mechanocytes responsible for microenvironment transfer during heterotopic transplantation of hemopoietic tissue from fibroblast clones in monolayer cultures. Fibroblast colony forming cells (FCFC) are readily released from tissue structures together with hemopoietic elements and are contained in bone marrow cell suspension at a concentration of 1 x 10(-5)-10 x 10(-5). Pretreatment with trypsin of bone marrow fragments increases the content of FCFC in bone marrow cell suspension. Trypsin releases from the bone marrow and additional fraction of FCFC (trypsin-dependent FCFC), which are more strongly bound to tissue structures and are likely to be injured in the course of routine suspension of hemopoietic tissue fragments. The ratio of the number of trypsin-independent and trypsin-dependent FCFC is approximately 1 : 10.
2194. [Current status of the leukemia problem].2195. [Afferent and central mechanisms of the osmoregulating reflex from the liver following hypothalamic deafferentation].
作者: M B Matveeva.;V V Osipovich.;I A Zhuravin.;B F Tolkunov.;Ia D Finkinshteĭn.
来源: Fiziol Zh SSSR Im I M Sechenova. 1981年67卷8期1251-7页
In anesthetized cats, 52 units of the hypothalamic supraoptic nuclei out of 65 retained the ability to respond to the osmotic stimulation after dissection of the brain stem (cerveau isolé). Administration of 1.0 ml 5% NaCl solution into the v. porta decreased the firing rate in 9 units and increased it in 43 units. The latency and the maximum reaction time were 30-100 sec and 2-6 min, resp. The data obtained suggest a humoral link in the reflex from the liver osmoreceptors.
2196. [Clonogenic cells in tumors and their reaction to irradiation and chemotherapeutic agents].2197. [Analysis of lymphocyte subpopulations and the mechanisms of their influence on hematopoietic cell differentiation].2198. [Electrokinetic properties of microorganisms as dependent on culture conditions].
The electrokinetic properties of cells were studied with the batch and continuous cultures of Bacillus megaterium and the chemostat culture of Candida utilis. The above cells growing at a higher rate had a higher electrophoretic mobility and a greater negative zeta potential; this seems to stem from the accumulation of negatively charged groups on their surface. The bacterial cells had higher values of electrophoretic mobility and electrokinetic potential comparing to the yeast cells; the electrokinetic properties of the bacterial cells changed more with a variation of the growth rate than in the yeast cells.
2199. [Heterogeneity of the stromal precursor cells of human and guinea pig bone marrow].2200. [Heterogeneity of the functional properties of macrocolonies of rat small intestine epitheliocytes].
The relationship was studied between the enzymatic activity of epitheliocyte macrocolonies of the rat small intestine and their size and the DNA synthesis rate. High degree of enzymatic differentiation was manifested by small colonies (1-4 mg) with a delayed 3H-thymidine incorporation into crypt cells. In macrocolonies sized over 5 mg with the normal DNA synthesis rate, the enzymatic differentiation was slightly marked. The evidence obtained indicates that epitheliocyte macrocolonies arising from individual stem cells have different functional properties depending on the DNA synthesis rate and the size of macrocolonies.
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