Structural organization of the layers III and V in the cortical fields (speech area, motoring, frontal inferior parietal) of the cerebral hemispheres and the nucleus caudatus have been quantitatively studied in 4 human beings. By means of a computer, area of profile fields of neurons, total volume of all the neurons and glyocytes in the histological section (total volumetric fraction of the neurons and glia) have been calculated, as well as percentage of the neurons having various size. The material is statistically treated. Certain morphological criteria of individual peculiarities have been established in the structural organization of the cortical and subcortical formations in the human brain. Individual variants in the value of the total volumetric fraction of the neurons and glia have been revealed, as well as peculiarities in composition percent of neuronal cells in the layers III and V. Differences in the area indices of the profile fields in separate persons and in various structures have been ascertained.

The composite adherent cell layer is produced in the culture of bone marrow fragments. On the contrary, in the culture of single cell suspension of bone marrow, only of monolayer of fibroblast-like cells and macrophages is created. After implantation of the adherent cell layer from the Dexter type culture but not from "fibroblast" culture beneath the renal capsule of syngeneic recipients the ectopic hemopoietic sites are formed. Regeneration of the adherent cell layer may occur only in the course of multilayer formation, i.e. one week after bone marrow transplantation but not three weeks after the formation of the adherent cell layer.

The proliferation of CFUs as measured by the 3H-thymidine inactivation test in organ cultures of mouse embryonic liver is maintained for 3-4 weeks. As regards the proliferation rate, CFUs located in the upper washed layers differ from those located in the deep culture layers. CFUs from washings manifested significant proliferation only in individual experiments and in the early times (3-9 days), while in the rest cases it remained at the zero level or was insignificant. CFUs from the deep layers rapidly proliferated for 3-4 weeks. Thus, the recovery of the content of CFUs and other hemopoietic cells in the washed layers is effected at the expense of proliferation of hemopoietic stem cells in the deep culture layers. After proliferation of CFUs ceases, their number in the cultures diminishes.

The experiment was carried out on lattice (Lactuca sativa) seeds flown in a biocontainer equipped with plastic detectors to record heavy charged particles (HCP). The purpose of the experiment was to determine the yield of aberrant cells as a result of irradiation, and to identify this effect as a function of HCP topography in the seed. The cytogenetic examination of flight seedlings revealed a significant difference between the seeds which were hit with HCP and those that remained intact. This indicates a significant contribution of the heavy component of galactic cosmic rediation into the radiobiological effect. The relationship between the radiobiological effect and the HCP topography in the seed was established: zones of the root and stem meristema proved to be most sensitive targets.

The effect of intense motor activity (swimming) followed by signs of physiological stress, on biosynthesis and phosphorylation of membrane proteins from different brain cells (neurons, glia) and sections (cerebellum, brain stem) as well as from liver, involved a significant decrease of 14C-methionine and 32P-phosphate incorporation related, probably, to inhibition of the physiological function, in all the electrophoretic fractions of proteins. In membrane proteins of cortical cells (particularly neurons), on the contrary, there was an increase of biosynthesis and phosphorylation in all the fractions. This seems to reflect an activation of cortical neurons for adaptation purposes.

The amount and distribution of glycogen in the brain tissue in closed craniocerebral injury were studied by electron microscopy. It is shown that 24 hours after the injury the number of glycogen granules in different areas of the brain, and especially in its stem, increases sharply. The glycogen granules are found in the cytoplasm of the neurones and their processes, in the synapses, and in the cytoplasm of the glial cells. The amount of glycogen reduced when the animals were given injections of agents stimulating the central nervous system (phenamine). In contrast, inhibition of the function of the central nervous system by injection of urethane and barbital caused an increase in the glycogen content. Under such conditions, the glycogen particles were predominantly localized in the processes of the perivascular astrocytes. The change in the glycogen content is associated with the effect of the craniocerebral injury and the different functions of the central nervous system on the activity of the enzyme gamma-amylase which is concerned with the hydrolysis of glycogen and the ultimate formation of glucose, the most important energy substrate of the brain.

The effect of insulin on the process of endogenous and exogenous spleen colony-formation in mice of Swiss strain was studied. In mice that received insulin the endogenous colony-formation was depressed for a short time, this process being glucose dependent. The number of spleen exogenous CFU decreased when the donors of bone marrow received insulin. A modulate influence of the hormone on the stem cell cycle has been shown.

Pretreatment of mouse bone marrow cells with rabbit antiserum to mouse brain (RAMB) decreases the capacity of these cells to form granulocyte-macrophage colonies in agar culture in vivo (CFU-DC) and does not affect the formation of colonies in agar culture in vitro (CFU-C). Mouse bone marrow CFU-DC are analogous to the pluripotent hemopoietic stem cells (CFU-C) forming spleen colonies in lethally irradiated mice as regards the ability for being inactivated with RAMB but differ from CFU-C. CFU-DC were found in the mouse thymocyte population.

Intravenous inoculation of killed Bordetella pertussis vaccine into BALB/c, CBA, C57Bl/6 mice or (CBA x C57Bl/6) F2 hybrids 1 day or 3 days before sublethal irradiation (5.5 Gy) was shown to sharply increase the endogenous colony formation in the spleen 9 days after irradiation. Moreover, the CFUs content of the spleen and bone marrow was also enhanced 1 and 3 days after vaccination of the mice with 10(10) cells B. pertussis as revealed by the exocolonization technique (Till and McCulloch). Thus, a single injection of B. pertussis vaccine hastened the hematopoietic recovery after irradiation.

Thymocytes of mice of different H-2 haplotypes are capable of releasing into culture medium an activity similar to that of stem cell inhibitory factor (SCIF) as regards suppressing action. All the test supernatants caused a decline in the number of hemopoietic colonies in the spleens of lethally irradiated (830 rad) syngeneic recipients. During study of the SCIF effect on bone marrow cells of different H-2 haplotypes, none of the strains appeared to be resistant to its action, which, probably, indicates the absence of genetic restriction of SCIF suppressive activity. Unlike migration inhibitory factor, SCIF does not appear to possess strain specificity.

A study of the fine structure of cells obtained from the transformed cloned culture of strain L, that have developed from a single cell, demonstrated several different cell types. The clones contained both non-differentiated and poorly-differentiated cells. The presence of morphotypical signs in the poorly-differentiated cells allowed to reveal some cell clone types and the direction of their specialization process. The study confirms the idea on the presence of the stem cell elements in the transformed cell culture of strain L causing the heterogenous way of cytodifferentiation and determining the long-term stability of cell polymorphism in this cell strain.

Experiments on mice have shown that severe mechanical trauma brings about phasic changes in the kinetics of hemopoietic stem cell migration. Within the first four days after the trauma the migration of stem cells gets intensified and returns to normal by day 8. This reaction is regarded to be a defence one, since it guarantees the function of the most important component of immunity, namely the organs where stem cells differentiate as T and B lymphocytes.

The activated T lymphocytes release in the culture medium a factor inhibiting the ability of hemopoietic stem cells to form hemopoietic colonies in the spleens of lethally irradiated recipients. An analysis of the effect of this factor on hemopoietic colonies was carried out. Its inhibiting effect was not related to the process of opsonization and to changes in the migration of spleen cells in the irradiated organism. No marked changes in the ratio of erythroid, myeloid and megakaryocytic foci were found in the spleens of irradiated mice which received the syngeneic bone marrow cells treated in vitro by the factor of stem cell inhibition: all three sources of hemopoiesis suffered under its effect to the same extent and their total number of the spleens was sharply reduced. Some mechanisms of the effect of the factor of stem cell inhibition on the formation of hemopoietic foci are discussed.