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Biomedical subjects

G V Papaian

Publications and source records attributed to G V Papaian.

At least 19 recordsLinked to original sources
PubMed1991

[Biometric studies in the cytological diagnosis of dysplasia and cancer of the uterine cervix].

Morphometric parameters were measured and specific light optic features of epitheliocyte nuclei examined in the cytologic preparations from 67 patients with various abnormalities of the cervix uteri multi-layer squamous epithelium by a present-day long-distance microimage analyzer. The most informative biometric parameters were detected, role of DNA cytophotometry defined, and algorithm of differential diagnosis between benign conditions, dysplasia, and carcinoma developed.

Female↗
PubMed1990

[Biometric research in the cytomorphological diagnosis of endometrial lesions].

Morphometrical and optical density (including DNA content) parametres of nuclei of the endometrial epithelial cells in smears of endometrial aspirates obtained from 57 women without endometrial disorders with hyperplastic, precancer conditions and endometrial cancer have been measured by using television image analyzer IBAS-2. Biometrical data have demonstrated a good correlation with cytomorphological diagnostic criteria and in 85.7% they have facilitated discrimination of the normal and hyperplastic epithelium from precancer and high differentiated endometrial cancer.

Adenocarcinoma↗
PubMed1989

[Biometric research in the diagnosis of precancerous states and endocervical cancer].

Smears of the endocervical channel taken from 58 patients with various endocervical conditions (reserve cell hyperplasia and dysplasia, reserve cell carcinoma in situ. Adenocarcinoma in situ, invasive glandular and poorly differentiated carcinoma) were stained by Feulgen method. Morphometrical (surface, perimeter, maximum and minimum diameter) and light microscopic (mean optical density of staining, its dispersion, DNA content) parameters of the epithelial cell nuclei were measured by means of telemetric image analyzer. The most informative biometrical indexes are found, the role of the DNA cytophotometry in the differential diagnosis is determined, the algorithm of the automated cytomorphological diagnosis of the dysplasia and endocervical carcinoma is developed.

Adenocarcinoma↗
PubMed1988

[A trial of digital television cytophotometry].

A possible application of modern TV analyzers of microimages for absorption cytochemical investigation is considered. Photometric properties of the TV system are evaluated and methodical approaches to their improvement are given. Data on TV and scanning cytophotometry are compared when studying DNA contents in cells of different types.

Animals↗
PubMed1987

[A scanning cytophotometer for the analysis of closely contiguous objects].

A measuring complex including microscope-photometer and computer is described to be used for scanning of a sample inside of an arbitrary contour. The complex is supplied with a television channel for simultaneous control of the sample and photometric diaphragm, and also with a manual manipulator for setting the boundaries of the informational zone. At the end of scanning the cytophotometric and morphometric data are registered.

Computers↗
PubMed1984

[Inhibitory analysis of the functions of the oxidative metabolic systems of tumor cells in tissue culture].

As has been previously reported an increased intensity of light-induced green fluorescence is observed for some tumor cells. The present paper deals with the cause of this phenomenon, employing for this hepatoma cells of line HTC acted upon with 2,4-DNP, amytal and malonate. It has been shown that the light-induced increase in green fluorescence in cells is due to the oxidation of NADH-dehydrogenase, a mitochondrial flavine-containing enzyme, occurring at the time of fluorescence induction. The increased intensity of green fluorescence of flavoproteins in tumor cells is associated with an infringement in oxidation of NAD-dependent substrates in these, and with the activation of the reverse electron transport in the oxidative chain. The exciding light activates NADH-dehydrogenase and accelerates the translocation of reduced equivalents from this enzyme, which results in its oxidation, and thus--in the observed effect of increased intensity of green fluorescence.

2,4-Dinitrophenol↗
PubMed1983

[Microfluorimeter for chromosome study].

A microfluorimeter is described for estimating amounts of chemical components in individual cells or in chromosomes, and for registering these components' distribution along the chromosomes. To solve the former problem, photoelectrical photometry of the object's fluorescence intensity is employed. To solve the latter problem, the photographic technique is used--making photos of metaphase plates in automatic or semiautomatic regime of exposure, with the following measuring of the intensity of the chromosome image on the negative performed on the same apparatus. The results of estimation of DNA content in individual chromosomes of Muntiacus muntjak are presented.

Animals↗
PubMed1982

[Characteristics of "photo depletion" of the green fluorescence of tumor cells].

The green (oxidized flavoproteins) fluorescence intensity was found to increase during investigation of NADH and oxidized flavoproteins fluorescence with the use of optimal excitation of different fluorescence bands. This effect was observed under excitation with blue light (436 nm). It is suggested that in some malignant cells, the structure of flavoproteins (probably of mitochondrial ones) may be altered in the way of increasing the quantum yield under the action of light irradiation.

Animals↗
PubMed1982

[Use of scanning cytophotometric data for the analysis of the distribution of an absorbed substance in cells].

Methods of quantitative evaluation of the structure of cytological objects based on the data of scanning microphotometry are described: calculation of histograms (weighed, average, reduced) and coefficients of relief and texture. Besides, the object is presented as a digit field or tones of gray field and a pseudorelief. Particular examples of practice in cytochemistry are given on applying the above characteristics.

Absorption↗
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↗