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L L Litinskaia

Publications and source records attributed to L L Litinskaia.

At least 19 recordsLinked to original sources
PubMed1991

[The intracellular significance of pH, its dynamics and possible role in regulating cell functions].

The intracellular and intralysosomal pH were studied on living monolayer cell cultures SPEV (pig embryo kidney), CHC (Chinese hamster's fibroblasts), NGUK-1 (neurinoma of Gasser's gland of rat), and also on primary cell cultures of rat's hepatocytes and chick embryo fibroblasts. In cytoplasm and lysosomes of these cells were found out pH changes during cells cycle and cell cultivation. There was also showed a heterogeneity of different parts of cells and lysosomes, and circahoral pH oscillations were registered. So there was found a spatial and temporal pH mosaity of living cells. The probable role of intracellular pH changes via regulator of cell vital activity is discussed.

Animals↗
PubMed1991

[Intravital determination of pH gradient between the cytoplasm and lysosomes in human fibroblasts in the normal state and in hereditary storage diseases].

Presented are the results of measurements of pH in cytoplasm and lysosomes of skin fibroblasts of healthy donors and patients with lysosomal storage diseases, mannosidosis, Fabry, Krabbe disease. The pH value was estimated in the stationary phase of growth using neutral red (lysosomes) and fluorescein diacetate (cytoplasm). It was shown that the cytoplasmic pH value in pathological cells didn't virtually differ from the control values. The intralysosomal pH value in fibroblasts of patients with mannosidosis and Fabry disease was essentially increased, which correlated with the size increase of these organelles upon the accumulation of unsplit compounds. This led to the decrease in pH gradient between the cytoplasm and lysosomes in the pathological cells, an increase in intralysosomal pH along with hereditary deficiency of enzymes could bring about the retardation of catabolic processes in lysosomes.

Cells, Cultured↗
PubMed1990

[Seasonal changes in lysosomal pH of peripheral blood cells of healthy subjects].

We studied pH values in lysosomes of peripheral blood white cells of 49 blood donors using the two-wavelengths (470 and 450 nm) microspectrophotometry of neutral red after supravital in vitro staining. In polymorphonuclear leucocytes lysosomal pH reaches the highest values in August-September (6.98 +/- 0.04) and the lowest--in February-March (6.23 +/- 0.09), p less than 0.05.

Adolescent↗
PubMed1990

[A pH increase in human fibroblast lysosomes during accumulation of non-hydrolysable compounds].

The changes in intralysosomal pH were measured in the stationary phase of normal human embryonic fibroblast growth under sucrose loading over a period of 6 to 120 hours and in cells with a typical lysosomal storage pathology, Fabry's disease, using a vital indicator dye, neutral red. It was shown that long-term hypertrophy of the lysosomal compartment during intracellular accumulation of non-hydrolysable compounds is concomitant with a pH increase, on the average, by 0.4 units. The highest values of pH (7.0-7.2) were seen in large-sized heterogeneic lysosomes of pathological cells. It is suggested that an increase in intralysosomal pH during accumulation of non-hydrolysable compounds leads to deterioration of conditions that are favourable for the acidic hydrolase function.

Cells, Cultured↗
PubMed1990

[Role of intracellular pH in the development of resistance of leukemic cells to antineoplastic drugs].

Intracellular pH (pHi) of mouse lymphoid leukemia P388 cells was measured at the wavelength of 518 and 570 nm of fluorescein: pHi of rubomycin-sensitive P388 cells was higher than pHi of the cells resistant to this antitumour antibiotic (6.98 +/- 0.04 and 6.63 +/- 0.03, respectively, P less than 0.001). The role of pHi is established during induction of the resistance of tumour cells to the antitumour drugs.

Animals↗
PubMed1987

[Effect of a pH change in the medium and cytoplasm of cultured cells on the rhythm of protein synthesis].

A circahoral rhythm of protein syntheses similar to that in monolayer hepatocytes was discovered in cell culture of Chinese hamster fibroblasts. Studies on the effects of pH changes in the culture medium and cultured cells on different parameters of protein synthesis showed some pH-dependent changes of predecessor pool and of its incorporation intensity into proteins. At the same time changes in a relative incorporation of the predecessor into proteins (with a correction for the pool) were insignificant. This value characterizing the productivity of protein synthesis does not seem to be directly associated with pH changes in the cells. The mean period of the rhythm of protein synthesis and intracellular pH was not changed with medium pH alterations.

Animals↗
PubMed1986

[Change in cellular pH in hyperthermia and hypoxia].

Change of pH of cultivated cells (Chinese hamster fibroblasts and pig embryonic kidney cells) was studied during their incubation under oxygenation conditions and at different temperatures using microfluorimetry with fluorescein diacetate. It was shown that pHc was 7.0 at temperatures 22-37 degrees C. Hyperthermia and hypoxia resulted in cell acidity. The effect was enhanced with an increase in the period of exposure to both agents. Intracellular pH more acid values were noted in the effect of hyperthermia in the presence of hypoxia or exogenous pH acid values. The authors made a conclusion of the importance of a degree of acidity of the intracellular medium for the survival of cells irradiated under hyperthermia conditions.

Animals↗
PubMed1982

[pH dynamics in the lysosomes and cytoplasm of tissue culture cells measured intravitally using the indicator dye neutral red].

A method of pH determination in the cytoplasm and individual lysosomes of intact living cultured cells is proposed using an indicator dye--neutral red (NR). The pH value of an investigated structure stained with NR is from the ratio between its optical densities at two wave lengths, the one corresponding to the isobestic point (lambda = 470 nm), and the other--to the absorption maximum of the neutral form of the dye (lambda = 450 nm). This method enabled us to make pH determination in the range from 4.5 to 7.2; the accuracy of the method reaches +/- 0.36 at pH 4.7 and diminishes to +/- 0.16 at pH much greater than 5.5. Using this method for the culture of pig kidney embryonal cells and Chinese hamster fibroblasts a heterogeneity of lysosomes was found with respect to the average pH value, oscillating ultradian changes in intralysosomal pH values, and the relationship between the changes and the size and average pH values of lysosomes. It is shown that the accumulation of NR in lysosomes depends on the pH gradient between lysosomes and the cytoplasm, which diminishes with the development of non specific cell response under the influence of some agents) high NR concentrations, inhibitor of glycolysis, or uncouplers of oxidative phosphorus lotion).

Animals↗
PubMed1981

[Feasibility of maintaining the structure and amount of DNA in nuclei of different cells during acid hydrolysis].

Effects of different types of fixation on preservation of DNA structure and amount in human leukocyte and chicken red blood cell nuclei stained according to Feulgen were studied. Regardless of hydrolysis conditions (5N HCl, 22 and 37 degrees C) the best results were obtained with use of a 95% ethanol-glacial acetic acid mixture (3:1) containing 2% of formaldehyde characterized by its independence on the fixation duration (other fixatives require the selection of the optimal fixation time), a satisfactory preservation of the native nuclear shape and of the chromatin structure, and by its ability to fix the maximal amount of reactable, aldehyde groups within DNP during a long period of time. In ethanol fixation, addition to the hydrolyzing solution of 20% of polyethylene glycol 6000 results in a stable plateau on the hydrolysis curve and in an increase of DNA-fuchsin amount by 5-32%.

Acetates↗
PubMed1979

[Factors affecting the course of DNA acid hydrolysis in carrying out the Feulgen reaction].

Literature data concerning acid hydrolysis of DNA during the Feulgen procedure are reviewed, with emphasis being made on the dependence of Schiff-apurinic acid binding on the fixation technique, the temperature of hydrolysis and acid concentration, the rate of extraction of depolymerized DNA fragments, the nucleotide composition of DNA, the chromatin state, and on the composition of nucleoprotein. Some practical considerations for optimization of the Feulgen procedure for a precise quantitative determination of DNA amount are given.

Animals↗
PubMed1976

[Scanning intergrating cytospectophotometry of tightly apposed micro-objects (as an example, a study of the circadian rhythm of RNA and protein concentrations in different neuron--neuroglia systems)].

A scheme of electron aperture is described which permits a scanning intergrating cytospectrophotometry of adjacent microobjects. Results are presented of such cytophotometry to determine RNA and protein content in various neuron--neuroglia units of the rats studied every 4 hours during 24 hours period. Contraphase character of circadian fluctuations has been shown for RNA level in cerebllum Purkinje cells, hypothalamus supraoptic neurons and spinal cord motoneurons as compared with the fluctuations in corresponding glial satellite cells. Protein content fluctuations were of contraphase character only in the spinal motoneurons and in their perineuronal glia, whereas in all the other neuron-neuroglia units the period of fluctuations was rather similar in the neurons and in the glial cells. A great value of quantitative cytochemical methods is outlined to carry out a functional biochemical analysis of nervous tissue cells.

Animals↗