Biomedical subjects

N P Nechaeva

Publications and source records attributed to N P Nechaeva.

15 recordsLinked to original sources

PubMed1986

[Cytotoxic effect of lymphocytes on autologous blood monocytes in the presence of streptococcal group A antigens in patients with primary erysipelas].

The present work deals with a modification of the cytotoxic test for the determination of the cytotoxic activity of lymphocytes in infectious diseases. This modification is based on the use of the suspension of mononuclear blood cells, simultaneously containing effector cells (sensitized lymphocytes) and target cells (autologous monocytes). The cytotoxic effect on monocytes is observed after the preliminary incubation of nonadhering cells (lymphocytes) with the antigen of microorganisms causing the infectious process. A statistically significant increase in the cytotoxic activity of lymphocytes was recorded in patients with primary erysipelas at the acute period of the disease. The cytotoxic effect has been found to persist at a high level for two weeks. By the end of the disease this effect drops to the level characteristic of clinically normal persons. An elevated level of the cytotoxic activity of lymphocytes in the presence of streptococcal antigens of one type has been detected in 72% of patients with primary erysipelas. This indicates that type-nonspecific streptococcal antigens take part in the formation of delayed hypersensitivity, which is also confirmed by the data obtained in animal experiments.

Animals↗

PubMed1976

[Lincomycin formation by strain R-367 on a complex medium not containing corn steep].

A new complex medium for biosynthesis of lincomycin by strain R-367 was developed using one-factor experiments and mathematical schemes of planning. A complex of mineral salts containing nitrogen, sulphur, phosphurus, magnesium and trace elements was introduced into the content of the new medium. This provided elimination of corn steep liquor from the medium. The linomycin production level in the fermentation broth with the use of the new medium was at an average 2.5 times higher than that on the initial medium containing corn steep liquor.

Culture Media↗

PubMed1975

[Optimization of the nutrient medium makeup for the biosynthesis of carminomycin using mathematical methods of experimental design].

The nutrient medium for biosynthesis of carminomycin by Actinomadura carminata, strain 4281 was optimized with the methods of mathematical planning of the experiment. The starting variant of the medium, production of carminomycin on which was assumed equal to 100 per cent was enriched during the experiments carried out according to the patterns of the orthogonal latin squares. The production levels of carminomycin on the above medium was more than 3 times higher than those on the starting medium.

Actinomycetales↗

PubMed1975

[Isolation of new species of the genus Actinomadura on selective media with streptomycin and bruneomycin].

In the screening programme using selective media with streptomycin (25, 50 and 100 gamma/ml) and bruneomycin (0.5, 1 and 2 gamma/ml) 3 unusual actinomycetous cultures forming short, rarely long chains of straight, hook-like or spiral spores with 1 or rarely 2 turns were isolated. The study of the cell wall composition of the isolates showed that the walls contained meso-diaminopimelic acid and a sugar madurose. On the basis of the morphological structure and the cell wall composition the isolates were classified as belonging to Actinomadura. Comparison of the cultures with the Actinomadura species described in the literature showed that the isolates were new species of the genera, i. e. Am. coerulea sp. nov., Am. cremea sp. nov. and Am. salmonea sp. nov.

Actinomycetales↗

PubMed1974