The model of closed brain trauma in mice using stem hematopoietic cell cloning methods has shown inhibited endogenous spleen colony formation and reduced number of reticulocytes in blood circulation during early periods subsequent to traumatic procedure. Maximal inhibition of bone marrow function occurs 4 days after trauma and is accompanied by a dramatic reduction of thymus weight and cellularity. The observed changes in bone marrow function can be one of the important factors leading to lower resistance of the organism to infections during early periods after brain trauma.

In this work, the regularities in the occurrence of a highly pronounced postirradiation increase in CFUf of bone marrow (CFUf "peak") were investigated and quantitative approaches permitting to predict absolute CFUf "peak" values at various radiation doses developed.

The dynamics of impulse activity of the cerebellar cortex neurons demonstrated in acute experiments on nembutal-anesthetized and diplacinum-immobilized cats bore evidence that the cerebellum participates in the organism's response to hypoxia. The Purkinje cells proved to be more resistant to hypoxia than the neurons of the neopallium, archipallium, and some other structures of the brain stem.

The experiments with the cultivated Chinese hamster cells showed that the incubation of cells with (phosphatidylcholine+cholesterol+7-keto-cholesterol)--containing liposomes (4:3:1 by weight) during two hours leads to a decrease in the effectiveness of colony-forming up to zero, while the (phosphatidylcholine+cholesterol-containing liposomes (1:1 by weight) reduce the effectiveness by 90%. Furthermore, the cholesterol-containing liposomes cause the decrease of the number of colonies with maximal size, accompanied by the increase of the number of colonies with middle size.

Using the developed method of modelling the curves of the fraction of labelled indexes (FLI) in the small intestine epithelium, a relationship was found between the FLI shape and duration of the S phase and the whole generation cycle for various generations of proliferating crypt cells. On the basis of the comparison between the theoretical and experimental FLI the normal values of the generation cycles along the crypt were specified for various intestinal parts. FLI were shaped along the crypt at various time intervals after irradiation. As a result, the data were obtained on the correlation between the duration of generation cycles and their phases during the postirradiation period and for various cell generations.

The functional state of granulomonocytic hemopoietic stem cells was investigated in 72 premature infants in the neonatal period. New data were obtained on the concentration of committed granulomonocytic precursors, and on the characteristics of the phenotype of monocytes--the final differentiation component of this series. These data have verified the present notions on the features of nonspecific adaptation reactions in premature newborns.

A selection system for isolating DNA sequences with transcription-promoting activity by their functioning in bacterial cells has been proposed. Tobacco nuclear DNA fragments were inserted in front of the promoterless neomycin 3'-phosphotransferase II (NPT-II) gene and promoter-like sequences were identified by their ability to restore NTP-II activity in E. coli cells. One of these recombinant plasmids was introduced in tobacco protoplasts by direct gene transfer and transformed calli were isolated by kanamycin selection. The NTP-II expression in regenerated transgenic plants were highest in root, slightly lower in stem and were practically absent in leaf. Sequence analysis of cloned segment showed the presence of conserved sequences essential for promoter activity in eukaryotic cells. A transcription start site was observed by S1 mapping. The size of protected fragments corresponds to the initiation of transcription 176 and 179 base pairs upstream the initiation codon in tobacco and 75 base pairs in E. coli.

The authors presented results of the assessment of morphological parameters and human embryo division rate in preimplantation when various schemes of superovulation stimulation were used in the routine for extracorporeal fertilization. A great number of embryos with favourable morphologic signs were obtained due to the routine. It was demonstrated that over 50% of all the embryos employed in various schemes of superovulation stimulation were at the stage of four and more blastomeres by the moment of their implantation to the uterine cavity 44-48 hrs after the in vitro insemination. A significant increment in the rate of embryo preimplantation development in vitro was revealed during superovulation stimulation with clomifen citrate in combination with an inductor versus the stimulation with the inductor alone. There was no difference in the frequency of conception induced by the transfer of embryos in all the groups exposed to simulation of superovulation.

It was shown that inhibition of bone marrow hyperplasia disappear due to injection of leu-enkephalin and dalargin as well as the increase of plasma leu-enkephalin by means of D-phenylalanine on the immobilized mice. The effect of enkephalin on hematopoietic precursor cells may be realized by inhibition of T-lymphocytes migration to bone marrow. Besides, direct specific influence of dalargin on myelokaryocytes is observed.

A study was made of the effect of the enkephalinase inhibitor D-phenylalanine on hematopoiesis during the immobilization stress. The long-term treatment with D-phenylalanine before the immobilization stress resulted in a significant increase of plasma ley-enkephalin in mice during the first day after exposure. Later the inhibition of bone marrow hyperplasia was recorded. There were no changes in hematopoiesis provided D-phenylalanine was injected after the immobilization. It is suggested that endogenous enkephalins may take part in the regulation of hematopoiesis at the early period of the stress reaction formation.

The bone marrow histological picture was studied in 13 patients with hairy-cell leukemia (HCL) who were followed up at the Hematological Centre in the Latvian SSR. The diagnosis was made or proved in all the cases, among them in 9 patients - on the basis of the proliferation type of leukemia cells in the bone marrow trephine biopsy that is characteristic of HCL. The analysis of the clinical and morphological features of the disease has permitted the authors to distinguish specific types of HCL: 1) splenic and bone-marrow variants predominantly were diagnosed clinically, 2) typical and atypical variants resembling malignant lymphoma or chronic lymphoid leukemia were diagnosed histomorphologically. The authors have recommended trephine biopsy+ for a wider use (as a more informative method as compared to sternal punction) in the diagnosis and differential diagnosis of HCL.

This paper discusses the effects of cochlear implantation on spiral ganglion neurocytes. It presents morphometric data and hearing measurements obtained from the treated animals. Cochlear implantation led to the death of some neurons and compensatory rearrangement of others. The number of the survivors was greater than that of degenerative cells. The functional variations were consistent with changes in the quality of spiral ganglion neurons and amplitude of the SSP EP peak at different postoperative intervals.

The authors have made an attempt to find out the reasons of IL-2 stimulation of spleen colony growth by in vitro (1 Gy) irradiated bone marrow cells. It was shown that the effect of IL on haemopoiesis manifests itself with merely small radiation doses implying that the influence of the preparation makes the process of haemopoietic organ repopulation start at a higher level of cell survival, which is presumably related to a more active repair of radiation-induced CFUs damages: this leads, with other things being equal (e.g. proliferation rate and f factor), to a higher yield of colonies than it is observed with the recipients protected with the exposed bone marrow only.

Using the technique of multistep selection, a thermoresistant substrain (TR RA-2T45) was obtained from a rhabdomyosarcoma RA-2 strain. The cells of this substrain retain the ability to form lung metastasis after a 20 minute treatment at 45 degrees C in vitro. The selection of cells for their ability to retain their reproduction activity is accompanied by the increase in their primary thermoresistance. The increased reproductive thermoresistance and primary thermoresistance of the selected cells is hereditary stabilized. Cells of both original strain and its substrain are capable of thermal tolerance, which makes perspective the selection for further increase in thermoresistance in RA-2T4t cell population.

The influence of myelopeptides on differentiation of bone marrow haemopoietic precursors cells in thymectomized and normal mice has been studied in vivo. The introduction of myelopeptides decreased the number of erythroid (E) colonies and increased that of granulocytic ones (G). This results in the decrease of initially raised E/G ratio in thymectomized mice (from 4.3) down to 1.3). Myelopeptides exerted no influence on haemopoietic precursors in normal mice (E/G-2.0).

No colonies were found in the spleen at "early" times (7-8 days) after irradiation of mice with doses of 8-9 Gy, while at "later" times (after 15 days) a confluent growth of the colonies was observed. The endogenous splenic foci of haemopoiesis of the "late" type were characterized by the preferable growth of granulocytic colonies.

The authors present data concerned with a long-term (up to 20 years) prophylactic medical observation over 103 patients with pronounced stable leukopenia. The different pathological processes associated with the development of the leukopenic syndrome were identified as were the reactive shifts in the medullary hemopoiesis of varying intensity. The shifts turned out nonspecific for all the disease entities under study.

Granulocyte-macrophage progenitor cells (CFU-GM) were found in the intima of human atheromatous aorta. Granulocyte-macrophage colonies were recovered on the 14th day of culturing of intimal cells suspensions on agar. Medium conditioned by normal leukocytes in the presence of phytohaemagglutinin was used as a source of the colony-stimulating factor. Grossly normal and atheromatous intima contained different number of CFU-GM. No GM were recovered from fibrous plaques. By light and electron microscopies, the injured aortic intima contained the clusters of blood-born cells that were at various stages of granulocytopoiesis (including blasts and mature cells) and poorly differentiated lymphocyte-like cells. The results obtained suggest that in human aortic intima proliferation and differentiation of CFU-GM occur at early stages of atherogenesis, prior to fibrous plaque formation.

The cortisol-resistant PNA+SC- --1+Thy--1+-thymocytes are the target cells for the thymocyte growth factor (THGF), which is produced by the lines of transformed precursors of T-lymphocytes (PTL). These cells have the same properties and markers as the intrathymic PTL. The bone marrow cells do not proliferate in response to THGF but acquire that ability after the influence of thymic hormones, which induce the maturation of PTL. Thus, THGF is the autocrine growth factor of intrathymic PTL.