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N V Smirnova

Publications and source records attributed to N V Smirnova.

At least 19 recordsLinked to original sources
PubMed2005

[Characteristics of p53 protein stabilization in cells of patients with ataxia-telangiectasia after gamma-irradiation].

Stabilization of P53 protein in cells isolated from patients with a grave hereditary disease ataxia-telangiectasia (AT), characterized by strongly enhanced sensitivity to ionizing radiation and impairment of cell cycle control after DNA damage, was studied. The level of expression of these reactions by patients may vary, and it tends to be linked with the severity of the disease. In all AT strains studied, both acquired by the authors and obtained from foreign colleagues, we observed the alteration of timing and character of stabilization of P53 protein, after the action of ionizing radiation in sublethal dosage, as compared to that in cells from healthy donor.

Ataxia Telangiectasia↗
PubMed1999

[P53-status of cells from patients with progeria and ataxia-telangiectasia exposed to ionizing irradiation].

P53 protein expression and stabilization in cell strains derived from patients suffering from progeria and ataxia-telangiectasia following gamma-irradiation have been described. A similar pattern of P53-status in healthy donor and progeria patient cells was shown using immunofluorescent cell staining. In ataxia-telangiectasia cells (strain AT2SP) the P53 protein was not detected by the same method. These data well compare with literary evidence on a disturbed P53-status at ataxia-telangiectasia.

Adult↗
PubMed1993

[Indications and contraindications to glomectomy in patients with bronchial asthma].

Thirty-year experience in surgical treatment of more than 3,000 patients with severe and moderately severe bronchial asthma showed that unilateral glomectomy produces a stable positive result in 69.5% of patients in follow-up repiods of two and more decades. Clinical recovery occurred in 23.2% of patients. Immunocorrection methods, such as hemosorption, plasmapheresis, plasmacytopheresis, xenosplenoperfusion, and the use of splenoperfusate raise the efficacy of the operation to 80-90%. The indications and contraindications for glomectomy in patients with bronchial asthma and methods for immunocorrection treatment of patients after glomectomy were developed.

Anesthesia, Local↗
PubMed1991

Metabolic and ultrastructural characteristics of biosynthetic processes in the cerebral cortex at 3 months following a prolonged hemorrhagic shock.

Biochemical indicators (the content of ATP, total RNA and DNA, acid and alkaline phosphatase activity) and ultrastructural changes in cells of the nerve tissue were studied in the cerebral cortex of anesthetized dogs 3 months after they had sustained a 4-h hemorrhagic shock (arterial pressure = 40 mmHg). A new variant of reconstruction of cell membranes and organelles that develops in neurons and gliocytes of the brain in the process of adaptation 3 months after resuscitation is identified. This reconstruction variant is described by (a) the presence of a monolayer of a substance with a medium electron density with the incorporated dense granules instead of the common three-layer organisation; (b) the ability displayed by the organellar structure to detect "errors" in its organisation; (c) changes in the character of intercellular relations. The development of this variant of cell structure in the postresuscitation period is likely to be based on the information disintegration of a cell as a system, resulting in distortion of biosynthesis of supracellular ensembles and biological membranes of nerve cells in particular.

Acid Phosphatase↗
PubMed1991

[Effects of verapamil on the activity of Ca2+, Mg2+-dependent endonucleases in the nuclei of the dog liver during prolonged hypovolemic shock].

In the experiments of 23 mongrel anesthetized dogs it was established that the blockade of calcium channels with verapamil (0.1 mg/kg) significantly decreased the activity of Ca2+, Mg(2+)-dependent endonucleases in the nuclei of canine liver (after four hours of arterial hypotension, arterial pressure--40 mm Hg). Verapamil was injected intravenously 30 min before the beginning of haemorrhage. The infusion of verapamil to intact animals does not change the activity of the investigated DNA-endonucleases. The obtained experimental data demonstrate that verapamil effectively blocks the activity of endonucleases in the nuclei of canine liver in the conditions of an increasing permeability of hepatocytes' membranes which integrity is deranged during hypovolemic shock. The present investigation reveals a new molecular mechanism of defense of hepatocytes from the damaging effect of one of the pathogenetic factors of a terminal process, namely an increase in the activity of Ca2+, Mg(2+)-dependent endonucleases in the nuclei of the liver.

Animals↗
PubMed1990

[The effect of inhibitors of ionic passive transport on the structure of a cell population of Ehrlich's ascites carcinoma].

Triampur is a drug, containing triamterene and dichlotiazide, which inhibits passive influx of Na+ through cell membrane. Triampur was injected intraperitoneally to mice with the Ehrlich ascite carcinoma. The drug was injected in the exponential phase of tumor growth with 2 hour intervals within 24 hours. A subsequent sedimentation and fractionation of cells according to the cell cycle position displayed an additional peak in sedimentogram, that was absent in the control sedimentogram. This peak is due to cell blocking in G1-period; the pool of blocked cells contains 20-25% of the total cell population. If the drug was injected during 3 days and nights with 8-hour intervals, the pool of blocked cells amounted up to 40%. This effect is reversible: when the drug is cancelled, the peak of G1-blocked cells is reduced. Estimation of intracellular Na(+) and K(+) concentration and Na+, K(+) pump indicates a significant decrease in Na+ permeability in the blocked cells due to Triampur effect. The obtained data well compare with an idea of the importance of increasing a passive influx of Na+ for G1-S transition, and indicate a possibility to affect the structure of tumor cell population via the system of intracellular ionic homeostasis.

Animals↗
PubMed1990

[Effects of intracellular Na+/K+ ratio on histone gene expression in ascitic cells of leukemia P-388 and Ehrlich cancer].

The intracellular Na+/K+ ratio was studied for its effect on histone genes expression in Ehrlich carcinoma and leukemia P-388 ascites cells. After equilibration with certain Na+/K+ ratio buffers at 0-4 degrees C the cells were treated during 1 h at 37 degrees C with ouabain added to the corresponding medium. Then total RNAs were extracted and analyzed by the reaction of blot-hybridization with histone genes cluster in plasmid p604. The maximal level of histone genes expression in leukemia P-388 cells was observed under conditions when intracellular Na+/K+ ratio corresponded to those at S-phase of the mitotic cycle. In Ehrlich carcinoma ascites cells the expression of histone genes was not dependent on the Na+/K+ ratio. A conclusion is drawn that the intracellular ratio of monovalent cations is one of the possible mechanisms which regulates the gene expression during the mitotic cycle.

Animals↗
PubMed1990

[Effects of intracellular Na+/K+ ratio on expression of c-fos oncogene and beta-actin gene in ascitic cells of leukemia P-388 and Ehrlich tumor].

The intracellular Na+/K+ ratio was studied for its effect on expression gene beta-actin and oncogene c-fos and activity of these genes during the mitotic cycle in ascites cells of leukemia P-388 and Ehrlich tumour. It was established that gene beta-actin was activated at high and low ratios of Na+/K+, while c-fos only at high ones. The expression of these genes during the mitotic cell cycle was due to changes in the intracellular Na+/K+ ratio. The obtained data showed an important role of intracellular homeostasis of monovalent cations in regulation of gene expression during the mitotic cell cycle.

Actins↗
PubMed1982

[Organization of the life-ensuring systems of spinal cord nerve cells in dogs].

By means of Klosovsky's impregnation method and injecting the vascular network with gelatin--indian ink solution with a subsequent additional staining of the cells after Nissl's method, interposition of neural cells of IX and VI laminae with the vessels and glia has been studied in the dog spinal cord at the level of L6. Sources of blood inflow and outflow from motoneurons and intercalated cells, average density of the capillary network, length of the capillary bed surrounding each cell have been defined; means of interaction of the neural cells with the surrounding capillaries has been estimated; diameter and length of the loop formed have been measured. The number of glia per 1 mm3 of the medullary tissue has been counted. Comparing the results of the investigation obtained, it has been stated that the function of the neural cell in the spinal cord determines certain peculiarities of its feeding systems. The motoneuron has a more adequate vascular ensurence than the intercalated cells of VI lamina. Getting blood from greater number of sources, the motoneuron possesses also some direct ways of the arterial inflow and a quick elimination of metabolic products. In spite of the fact that the vascular-capillary network in IX lamina is less dense, the proper microcirculatory bed of the motoneuron is developed much better. The number of cells being in contact with the capillaries and the length of the contacting surfaces in the motoneuron prevail over those in the posterior horn neurons. At the same time, the number of glial cells in VI lamina is greater than those in the inferior horns. A suggestion is made that the cells of this lamina get their feeding mediated via glia.

Animals↗
PubMed1981

[Changes in the structure of lamina IX of the lumbar enlargement of the spinal cord in dogs following limb amputation].

Neural cells, glia and capillary network in IX plate of L6 of the spinal cord were studied in 15 mature dogs (control) and in 15 dogs survived for 6 months after amputation of the right femur at the level of middle third. After injecting the vascular network with Indian ink--gelatin and after staining the neurons according to Nissl's technique, total amount of neuronal cells, alpha-motoneurons and glia were defined; section area of the body and nucleus of a-motoneurons, length of the capillary network around every alpha-motoneuron and capillary diameters were measured. Unlike the control and the contralateral side, in the ipsilateral IX plate the number of neurons decreased by 46%, the number of glial cells--by 22%, the length of the capillary network--by 38%; capillaries grew narrow. Amount of alpha-motoneurons did not differ from that of the control. Section area in the body of alpha-motoneuron decreased by 20%, in their nuclei--by 45%, and the length of the proper capillary network--by 42% as comparing to the control. compensatory hypertrophy in the contralateral IX plate was manifested in appearance of giant a-motoneurons, in increasing by 18% the length of the vascular network feeding them, in dilatation of capillaries and in increasing by 22% the number of glial cells.

Amputation, Surgical↗
PubMed1976

[Stimulating effect of histones on DNA synthesis in the regenerating rat liver].

Effect of exogenous histones, nuclear globulins and acid proteins on DNA synthesis is studied in regenerating liver of rats in which the synthesis of their own proteins and thus DNA replication are inhibited by cycloheximide. In these conditions histones from regenerating rat liver are found to stimulate 3H-thymidine incorporation into DNA of hepatectomyzed rat liver. Nuclear globulins and acid proteins from regenerating liver, and histones from intact liver produced no stimulating effect on DNA sythesis.

Animals↗