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I F Seĭts

Publications and source records attributed to I F Seĭts.

At least 37 records · Page 2Linked to original sources
PubMed1983

[High-molecular forms of DNA in the blood serum of rats with Zaidel's hepatoma].

Apart from heterogeneous high-molecular DNAs, two fractions corresponding to 17 and 20 MD of DNA and homogeneous with respect to mobility are to be found in preparations of nucleic acids of rat blood serum. The former fraction (17 Md) is greater than the latter in healthy animals. This ratio is reversed in the blood serum of rats with Zajdela's hepatoma. The relative predominance of 20 Md DNA is still more pronounced in ascitic liquid which washes tumor cells.

Animals↗
PubMed1983

[Changes in the intracellular localization of pepsinogen-synthesizing polysomes in the gastric mucosa of rats during N-methyl-N'-nitro-N-nitrosoguanidine-induced carcinogenesis].

A study was made of the distribution of pepsinogen-synthesizing polyribosomes in the rat's stomach mucous membrane, in the process of chemical carcinogenesis induced by N-methyl-N'-nitro-N-nitrozoguanidine. A sharp decrease in the content and proteolytic activity of pepsin is shown in cytosol and membrane-bound polyribosomes of the mucous membrane of the rat stomach due to the inducing substance. The appearance of this enzymatic activity is noted in free polyribosomes isolated from the rat stomach tumours.

Animals↗
PubMed1982

[Nonhistone proteins of the rat liver in malignant transformation by nitrosodiethylamine].

Qualitative and quantitative content of nonhistone chromosomal proteins (NHP) from normal and nitrosodiethylamine-transformed rat liver was studied. An increase in the protein/DNA ratio in tumor chromatin, as compared with that of normal tissue, was established. NHP were extracted from the chromatin with 0.4 N N2SO4 and fractionated with two-dimensional polyacrylamide gel electrophoresis. Coomassie staining revealed more than 80 fractions with molecular weights ranging 20-150 th. Some quantitative and qualitative differences in the patterns of NHP from normal and neoplastic tissues were observed. A conclusion is drawn that these differences may be related to structural and/or enzymatic components of NHP.

Animals↗
PubMed1980

[Low-molecular RNA in different rat liver and liver tumor cell fractions].

Low molecular weight nuclear RNAs (LMWN RNAs) from rat liver, Zajdela hepatoma and rat hepatoma induced by DENA have been studied. The changes in the relative content of nucleoplasmic U1 and U2 RNAs, nucleolus U3 RNA and chromatine 5S RNA have been discovered in both hepatomas. Whereas 8S1 and U3 RNA were found in polysomes from rat liver but not in those from Zajdela hepatoma.

Animals↗
PubMed1980

[Subcellular and molecular mechanisms of a defect in pepsinogen synthesis in cancerous stomach tumors].

The messenger RNA of pepsinogen from gastric tumors was found to show a lowered activity in providing the synthesis of a specific protein of gastric mucosa--pepsinogen in the acellular system. A relative amount of free polysomes in human gastric tumors is increased compared with the mucous membrane of the stomach. The pepsinogen messenger RNA of human gastric mucosa stimulates efficiently the in vitro incorporation of labelled leucin into the protein and induces the pepsinogen-pepsin synthesis in the polysome system of human gastric mucosa and rat liver.

Animals↗
PubMed1980

[Low molecular weight nuclear RNA of human gastric adenocarcinoma].

Low molecular weight nuclear RNAs (LMWN RNAs) isolated by thermal phenol fractionation from malignant tumor of the stomach and the mucous membrane of patients with gastric ulcer have been studied. There were found some differences in the relative content of U1 and U2 nucleoplasmic fractions as well as of loosely bound to a nucleolus U3 fraction of LMWN RNAs. The changes observed resemble those obtained earlier for experimental animal tumors.

Adenocarcinoma↗
PubMed1979

[Effects of low molecular weight nuclear RNAs on the activity of RNA polymerase II in isolated rat liver nuclei].

An attempt was made to elucidate the possible participation of low molecular weight nuclear RNAs in the transcription process. The parameters of the RNA synthesis cell-free system in isolated rat liver nuclei were studied for this purpose. Tissue homogenization in isotonic sucrose during isolation of the nuclei resulted in a loss of 4S nuclear RNA. The dependence of RNA synthesis on the salt concentration in the incubation medium is indicative of possible initiation of the RNA synthesis in this system. At salt concentration of 0.08 M 50-75% of incorporation is due to the activity of RNA polymerase II. Under these conditions the electrophoretically homogenous individual fractions of low molecular weight nuclear RNAs do not affect specifically the activity of RNA polymerase II. No evidence for the participation of low molecular weight nuclear RNAs in the mechanisms of heterogeneous nuclear RNA synthesis were obtained.

Animals↗
PubMed1979

[Low-molecular RNA subcellular localization and its binding strength with cellular structures].

Some fractions of low molecular weight (LMW) nuclear RNAs were shown to be present in the cytoplasm of rat liver cells. In addition to known 4S tRNA, 5S and 5,8S rRNAs U3 and 8S1 LMW nuclear RNAs, 8SII and 8SIII LMW RNAs have been detected in RNA preparations of free total and membrane-bound polysomes. The U3 and 8SI polysoma I RNAs seem to be associated with high molecular weight polysomal RNA. Using thermal phenol fractionation, that some LMW RNAs were shown to be slightly bound to the cellular structures whereas some others are bound more tightly. Considerable amounts of LMW RNAs are tightly bound to the chromosome-nucleolar apparatus. They can be extracted only at 85 degrees C. The data presented are discussed with regard to LMW nuclear and polysomal RNAs functions.

Animals↗
PubMed1979

[Cytoplasmic RNA biosynthesis in Erlich ascitic carcinoma cells under anaerobic conditions].

Cells of Ehrlich ascites carcinoma were incubated under aerobic and anaerobic conditions with 3H-uridine, and the amount and radioactivity of poly(A)-containing and poly(A)-non-containing fraction of cytoplasmatic RNA were determined. It is shown that RNA biosynthesis, as judged by the labeled precursor incorporation, is nearly similar to that under oxygen supply conditions. The specific radioactivity of poly(A)-containing fraction of cytoplasmatic RNA of cells incubated under anaerobic conditions was 2 times as much as that under aerobic ones.

Aerobiosis↗
PubMed1978

[Immunochemical, electrophoretic and enzymatic analysis of the pepsinogen-pepsin isoforms of human gastric mucosa and gastric tumors].

The obtained specific antiserum against the 1st isoform of pepsinogen of human gastric mucosa responds in immunodiffusion only to the 1st pepsinogen isoform but not to the IId and IIIth one. Human pepsinogen has no common antigenic determinant with pig pepsinogen. The methods of electrophoresis and immunodiffusion reveal the Ist, IId and IIIth isoforms of pepsinogen in human gastric tumors and their metastases, however, they do fail to show any enzymic activity.

Animals↗