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T V Osipova

Publications and source records attributed to T V Osipova.

At least 19 recordsLinked to original sources

[Current problems of occupational health in polyurethane production].

Prospective production of polyurethane is not safe for humans. This production is characterized by possible workers' exposure to chemical hazards mixture. The work safety includes cautionary and current sanitary supervision, implantation of sanitary recommendations concerning individual protective means also.

Adult↗

[The role of adhesion molecules (ICAM-1 and E-selectin) in development of diabetic microangiopathies].

AIM: To examine the expression of the intercellular adhesion molecule-1 (ICAM-1, CD54) on the surface of leukocytes and a soluble E-selectin (CD62) level in patients with diabetes mellitus type 1 (DM1) at various stages of diabetic nephropathy and retinopathy. MATERIAL AND METHODS: 42 patients with newly diagnosed and long-standing DM1 with presence or absence of microangiopathy (diabetic nephropathy and retinopathy) were examined. Routine laboratory, ophthalmologic tests, a special immunological test with ICAM-1 expression and soluble E-selectin (sES) examination were performed. RESULTS: The tests show increased ICAM-1 expression and sES level in all the patients vs controls. In newly diagnosed DM1 a high sES level was observed. In long-standing DM1 and absence of microangiopathy a sES level was also high. In patients with neovascularisation and proteinuria the sES level was two times higher than that in other subgroups. We also found an increased percentage of ICAM-1, CD54-positive lymphocytes and granulocytes in patients with microalbuminuria and especially with proteinuria and neovascularization. There were no correlations of ICAM-1 and sES levels with sex, DM duration, cholesterol and triglycerides. CONCLUSION: The findings show endothelium and leukocytes activation at early disease stages. Enhanced endothelium and leukocytes activation is associated with late complications.

Adult↗

[Gas chromatography in detection of toluene diisocyanate in biological medium].

The authors suggested a method of gas chromatography for detection of toluylene diisocyanate (TDI) in biologic material: liver, lungs, spleen, brain, kidney. The method includes TDI extraction from tissues by solvent, subsequent concentration and the extract chromatography by a device with electron capture detector. The method was tested in white rats.

Animals↗

Special differentiation requirements of original and enriched secondary cytotoxic T lymphocyte precursors (pCTL-2 memory cell) specific for the class I histocompatibility molecule.

The in vivo-induced pCTL-2 cells of the L3T4- Lyt-2+ phenotype specific for the H-2Kb molecule are converted into effector CTLs in mixed lymphocyte culture (MLC) in the presence of heat-treated donor stimulators much more efficiently when the donor and recipient differ from each other, not only in the major histocompatibility complex (MHC) class I (H-2Kb) (anti-B10.MBR B10.AKM) but also in the MHC classes I + II, i.e., Kb + Ib (anti-C57BL/6 B10.D2 (R101)). The differentiation of original pCTL-2 is enhanced as the result of a synergistic action of the Kb alloantigen and rIL-2 in small doses. The anti-Kb pCTL-2, after their separation from helper T cells non-adherent to the macrophage donor monolayer and their subsequent elution from it, give rise to pronounced differentiation in simplified conditions over 3 days in monoculture in the absence of both stimulators and rIL-2. It is suggested that spontaneous and highly efficient specific differentiation of the eluted pCTL-2 is due to a dramatically enhanced secretion of the CTL differentiation factor by pCTL-2 themselves, and in addition, rIL-2 can also contribute to the secretion of this factor.

Animals↗

Difference between antigen-binding receptor repertoires in effector cytotoxic T lymphocytes and their secondary precursors (memory cells) specific to H-2Kb.

The fine specificity of antigen-binding receptors was compared in pCTL-2 and secondary effector CTL (cytotoxic T lymphocytes) induced in vivo with the H-2Kb alloantigen in recombinant inbred mice. The lymphocyte preparations were enriched by elution from macrophage monolayers of various origins, including the donor (B6 strain), the H-2Kb mutant bm1, the H-2Kk allele B10.A(4R) and the recipient strain B10.D2(R101) as a control. Anti-Kb pCTL-2 eluted from third-party bm1 or B10.A(4R) monolayers gave rise to CTL progeny that lysed, equally well, both donor TC and those third-party TC from whose monolayer the pCTL-2 had been eluted, but which were unable to lyse irrelevant third-party TC. The lytic activities of secondary CTL whose precursors had been eluted from bm1 or B10.A(4R) monolayers were 6 and 12 times lower, respectively, than pCTL-2 eluted from the donor monolayer. Opposite results were shown for receptors of enriched secondary anti-Kb effector CTL. Irrespective of their elution source, whether donor, mutant or allele variant, the eluted effector CTL were able to lyse the donor TC to a similar degree and much more than the given third-party TC; moreover, they retained cross-reactivity in all cases. It is suggested that CTL receptors are homogeneous in specificity for a whole composite immunodominant epitope and differ from each other only in the affinity/lability of the combining site. In contrast, pCTL-2 can be separated into fractions: receptors of each fraction are strictly specific (with high affinity) to a particular portion of the same composite CTL epitope. It seems likely that the pCTL-2 receptor antigen-binding site is modified during pCTL-2 in vivo differentiation into effector CTL.

Animals↗

[Characteristics of the conditions for memory cell differentiation--the initial and enriched precursors of secondary cytotoxic T-lymphocytes (pCTL-2) specific for the histocompatibility class I molecule].

The in vivo induced pCTL-2 with phenotype L3T4- Lyt2- specific to the H-2Kb molecule, turn into effector CTL during 4 days in the mixed lymphocyte culture (with heat-treated donor stimulators) much more efficiently when donor and recipient are different from one another not only in MHC class I (anti-BIO, MBR BIO.AKM) but in I + II (Kb + Ib) ahti-C57BL/6 BIAD2(RIOI). The initial pCTL-2 differentiation in enhanced as a result of synergistic effect between the Kb alloantigen and rIL2. The anti-Kb pCTL-2, being separated from helper T cells by means of absorption onto the macrophage donor monolayer and elution from it, give rise to pronounced differentiation in simplified conditions, irrespective of the stimulator presence and without external rIL2. It is supposed that these phenomena are raised to secretion of the CTL differentiation factor by the eluted pCTL-2 themselves, and besides, rIL2 may promote for secretion of this factor additionally.

Animals↗

[The main difference between the repertoire of receptors of effector T-killers and their secondary precursors (memory cells)].

Receptor repertoire analysis of in vivo induced secondary cytotoxic T lymphocyte precursors (pCTL-2) was performed, using the technique of their specific adherence to macrophage monolayers with subsequent elution of the adherent pCTL-2 and their activation by heat-killed donor stimulator cells. The capacity of anti-H-2Kb pCTL-2 receptors to contact H-2Kbm has been revealed only in a minor pCTL-2 component whose progenitors were able to lyse mutant bm1 target cells (TC). Unlike poor cross-reactivity of CTL descended from anti-Kb, pCTL-2 which were eluted from the donor monolayer, CTL-progenitors of anti-Kb pCTL-2 eluted from bm 1 or B10. A (4R) third-party monolayers lyse in equal quantities the donor TC and those third-party TC from which they have been eluted, but fail to lyse other TC. Enrichment of pCTL-2 eluted from bm 1 or B10. A (4R) monolayers is 6- or 12-fold lower, respectively, than after their elution from the donor monolayer. The findings indicate that anti-class I MHC pCTL-2 are separated into fractions, with their receptors being strongly specific (with high affinity) to the particular fragment of the same complex epitope without cross-reactivity to other fragments. These data differentiate pCTL-2 receptors from effector CTL ones which are homogenous in specificity to a whole (single) complex epitope with variable degree of complementarity. A cardinal distinction of receptor repertoire between CTL, pCTL-2 and suppressor T cells specific to the same class I MHC molecule and alteration of the active site during pCTL-2 differentiation have been suggested.

Animals↗

[Allogeneic lymphocyte induction in vivo of highly active T-killers specific for the molecule of the H-2 class-I complex and the detection of their receptors in vitro].

The optimal conditions are found for in vivo irradiated lymphocyte induction of high cytotoxic T lymphocytes (CTL) specific to the H-2Kb molecule with a subsequent monoculture differentiation. B10.D2(R101) CTL have a pronounced excess as compared to B10.A (4R) CTL, with respect to lysis intensity of the same target cells (TC), and requires a lower term of the monoculture incubation in spite of their specificity to the same H-2Kb molecule. As the susceptibility of TC for CTL lysis is higher (M phi as compared to EL-4 thymoma cells), CTL are much more inactivated with the monoclonal antibodies to Lyt-2 and Lyt-3 antigens without complement. Anti-H-2Kb CTL differentiated in the monoculture cross react to TC bearing third-party H-2 molecules (Kk, Dq, Dk). Unlike a stable CTL adherence to the donor M phi monolayer, nonspecific CTL adherence to the syngeneic M phi monolayer declines in the presence of EGTA, and as a result of repeated detachment of lymphocytes. The findings give rise to study receptor affinity expressed on the in vivo induced CTL surface, the CTL receptor monoclonal antibody and the CTL differentiation factor.

Animals↗

[Response of lymphoid and hematopoietic tissues to the growth of syngeneic transplantable hemangiopericytomas in mice].

The growth of syngeneic hemangiopericytoma in CBA X X C57BL/6j)F1 male mice was attended by the development of leukemoid reaction. The spleen showed an abrupt increase of the area taken by the red pulp with a remarkable activation of erythropoiesis in the pulp. The peripheral blood developed erythrocytosis 7 days after transplantation of pericytoma followed by anemia.

Animals↗

[Hematopoietic tissue reactions associated with the growth of syngeneic transplanted tumors in mice].

Hemangiopericytoma growth in syngeneic male mice F1 (CBA X C57BL/bj) led to regular hemopoietic changes: an increase in the spleen weight, spleen cell count, in the number of colony-forming units (CFU). It also induced augmentation of myelopoiesis in the spleen and leukocytosis with a sharp increase of segmented granulocytes in the circulating blood characterized as the "leukemoid reaction" syndrome. The latter occurred even when the tumour cells were transplanted into the splenectomized host. Although less marked, this leukemoid reaction was also noted in advanced hepatoma transplanted to syngeneic male mice F1 (CBA X C57BL/6j). No leukemoid reaction was observed in these mice after grafting syngeneic strain of urinary bladder carcinoma.

Animals↗

[Kinetics of hematopoietic stem cells in the bone marrow of hepatectomized mice].

Two-thirds of the liver was removed from (CBA X C57BL/6j) F1 female mice. A significant increase of the number of endogenous colonies count in the spleen of partially hepatectomized mice was observed on the 5-th day after the operation. This increase was not associated with the changes in the number of stem cells in the bone marrow as partial hepatectomy at different times after the operation exerted no effect on the number of colony-forming units (CF1) in the bone marrow.

Animals↗

[Transplantable cancer of the urinary bladder and hemangiopericytoma obtained by means of the ectopic transplantation of tissues of the fetal urinary bladder].

Organ-like cysts appear to develop after subcutaneous transplantation of minced tissues of fetal urinary bladder into adult syngeneic recipients. These are multilocular cysts lined with epithelium and filled with secretion. Many months later they undergo a spontaneous malignant tranformation. Transplantable strains of vesical cancer and hemangiopericytoma have been obtained.

Animals↗