PubMed Health⌕ Search

Biomedical subjects

V I Gusikhina

Publications and source records attributed to V I Gusikhina.

13 recordsLinked to original sources
PubMed1990

[Structural basis of developmental changes in the cytoarchitecture of human neocortex transplants].

Early stages in development of transplants of the embryonal anlages of the human neocortex into the brain of mature rats have been studied at light optic level. The main attention has been paid to processes of proliferation, migration and differentiation of cells. Increasing amount of cells in the transplants takes place only at the expense of neuroepithelium; its reorganization results in a peculiar rearrangement of cells with formation of so called rosellas with numerous mitotically dividing cells. Owing to this growth the differentiating cells migrate from the rosellas radially, unlike their layer-by-layer organization in the control. These deviations are probably dominant in the disturbance of cytoarchitectonic organization of cells in transplants of neocortex in mature mammalia.

Animals↗
PubMed1986

[Development of methods of connecting severed nerve trunks to restore their integrity].

An experimental model of a seamless end-to-end joining of severed sciatic nerve (with gaps between the two ends 5-8 mm-wide) using an implanted arterial vessel was elaborated on random bred and inbred Wistar rats. Histological examination showed that nerve regeneration along the implanted arterial lumen was directly oriented and was not accompanied by neuroma formation which was always the case in the control. It took some nerve fibers 20 days to join the gap between the cut nerve ends. In 4 months myelination of regenerating fibers was observed in the blood vessel lumen, in 3 months the lumen was filled with bundles of myelinated fibers, and in 9 months the structure of the regenerating nerve was similar to that of the mature trunk observed in animals. The elaborated experimental model is to be employed in the studies of reparatory histogenesis in peripheral nervous tissues. The data obtained may be used in neurosurgery.

Animals↗
PubMed1985

[Transplantation of embryonal anlagen of the human neocortex into the brain of the rat].

A possibility for transplanting anlages of human embryonal neocortex into mature rat brain has been studied. Light- and electron-microscopic investigations demonstrate that the embryonal tissue of the human neocortex implants into the cerebral grey and white substance of mature rats. In the grafts cellular elements proliferate and differentiate, neuropil is formed. These results open certain perspectives for modelling investigations on histogenesis of neural tissues and on studying possibilities for clinical use of grafts of the human embryonal brain.

Animals↗
PubMed1982

[Changes in rat lymphoid tissue during ether and halothane anesthesia].

A comparative quantitative investigation on the level of 11-oxycorticosteroids (11-OCS) in the peripheral blood and on morphological changes in the lymphoid tissue has been performed on intact and adrenalectomized rats after 3 hours' ether and halothane anesthesia. Three hours after the ether anesthesia, the level of 11-OCS increases more than twice, halothane is not a stress-producing anesthesia. After the ether anesthesia and essential devastation of the lymphoid tissue occurs, resulted from degeneration and a decreasing proliferative activity of the cells. In the adrenalectomized animals, both after halothane and either anesthesia, there are no essential morphological changes. Thus, certain significant differences between hormonal and morphological changes after either the halothane anesthesia have been revealed, as well as the role of the adrenal cortex in this activity.

11-Hydroxycorticosteroids↗
PubMed1978

[Tissue specific effect of lymphocytic chalone isolated from rat spleen].

Chalone-containing alcohol extract from the rat spleen consisting of 8--10 substances of protein nature, according to the data of the disk electrophoresis, possesses a selective property to inhibit the entrance of human transformed lymphocytes into the phase of DNA synthesis. Injection of lymphocytic chalones to the mice allotransplants of a donor's skin grafts, which differ from the recipient by a strong antigen, temporally delays the rejection of the transplanted graft. In mice-recipients, the thymus treated with lymphocytic chalone is characterized by the depletion of the cortical substance.

Animals↗
PubMed1978

[Changes in the lymph nodes of adrenalectomized rats with staphylococcal poisoning].

Histological changes in lymph nodes and dynamics of 11-oxycorticosteroid levels in blood were studied in intact and adrenalectomized rats under staphylococcal intoxication. At early stages (up to 24 h) after staphylotoxin or staphylococcal injection, stress reaction of the organism, which produces a rise of corticosteroid level in blood, was demonstrated to play the major role in aplasy of the lymphoid tissue. At later stages, when the level of corticosteroids decreases, the lymphoid tissue begins to restore. In adrenalectomized rats, aplasy of the lymphoid tissue begins at later stages (in 3--4 days) because of a decreased amount of corticosteroids in blood. From the data obtained a suggestion is made that under intoxication, devastation of the lymphoid tissue occurs via mediated and direct action of the toxin.

11-Hydroxycorticosteroids↗
PubMed1976

[Changes in the lymphoid tissue and in the level of corticosteroids in staphylococcal intoxication and infection].

A complex quantitative study of changes of proliferative processes in lymphatic vessels on the one hand and changes of the level of corticosteroids in the peripheral blood in staphylococcal intoxication and infection in the same rats on the other hand has been carried out. In the work H3-thymidine has been used. The comparison of the obtained morphological data with the dynamics of the change in the corticosteroid level shows that the decay of lymphocytes, the devastating of light centers and the cortical substance of lymph nodes, an abrupt lowering of the amount of DNA-synthesizing and mitotically dividing cells take place in the period associated with a release of a great amount of corticosteroids into the blood. The drop of their level to control values goes in parallel with increasing the amount of DNA-synthesizing and mitotically dividing cells. The obtained data suggest that the leading role in those changes of the lympoid tissue which had been described by a number of authors in infectional processes is played by corticosteroids.

11-Hydroxycorticosteroids↗
PubMed1975

[Alterative and repair processes in lymph nodes under the direct and mediated effects of radiation].

Under study were the popliteal lymph nodes of rats at different times after total irradiation of animals (the 1st series), total irradiation with screening the left node (the 2nd series) and local screening of other parts of the body (the 3rd series). X-ray irradiation in all experiments was performed under standard conditions in dosage of 800 r. The amount of mitoses (MC 0/00) in light centers and cortical substance was counted in addition to histological alterations. In shielded lymph nodes (2nd series) mediate effects of irradiation were observed characterized by a decrease of the MK amount and massive death of lymphocytes in later terms than after direct effects (1st series). In irradiated nodes (3rd series) the reparative process was more rapid than in the first series due to migration of lymphocytes from non-irradiated parts of the body. The mediate effect of radiation results also in increased amount of plasma cells in lymphatic nodes of animals subjected to total irradiation (1st and 2nd series). It is suggested by the absence of such increase of amount of plasma cells in locally irradiated lymphatic nodes when screening other parts of the body (3rd series). availability of individual distinctions in the character of the lymphoid tissue response to effects of ionizing radiation puts a question of division of experimental animals at least into 2 subgroups which have different indices of proliferative processes.

Animals↗
PubMedDate not supplied

[The development of transplants of human embryonic neocortex in the anterior chamber of the rat eye].

Dorsolateral regions of embryonic human neocortex at 9-11 weeks of development were transplanted into the eye anterior chamber of rat. Significant changes, leading to the complete destruction of the original cytoarchitectonies occured during the first three days. Intensive neuroblast degeneration in cortical and interstitial zones as well as decrease of mitotically deviding cell numder were observed 3-6 hours after the transplantation. Neuroepithelial cells form rosettes in ventricular zone by the end of the first day. Rosettes turned into the centres of proliferation, mitotic activity restored to the initial level. Cells migrated out of the rosettes in radial directions. By the end of the third day almost all the cells in cortical and interstitial zones degenerated, transplant was almost completely represented by the ventricular zone cells. Number of mitotic figures exceeded the initial level almost three times, transplant was enlarged, its blood supply was absent. Since the 4-th day mitotic activity decreased, transplant underwent lymphoid infiltration and its complete destruction occured by the end of the second week.

Animals↗