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Biomedical subjects

O B Ermolova

Publications and source records attributed to O B Ermolova.

At least 19 recordsLinked to original sources
PubMed1989

[Determining the biological activity of levorin by the international standard of candicidin].

Levorin and candicidin represent close mixtures of heptaenic components. Their physicochemical and biological properties were also close. The antibiotics showed similar diffusive properties in their assay by the agar diffusion method. This made it possible to determine activity of the Soviet levorin standard by the International candicidin standard. For defining the levorin unit in the international units of candicidin, a scaling ratio of 9 was proposed.

Agar↗
PubMed1983

[Standardization of the index of biological activity of the multi-component antibiotic neomycin].

The characteristic features of determination of the biological activity of neomycin and its separate components A, B and C were studied. Different sensitivity of 5 test microbes to neomycins A, B and C was observed. Bac. subtilis ATCC 6633 and Bac. cereus, var. myc. 537 were the most sensitive to neomycin A. Sar. lutea were not sensitive to neomycins A and C. The diffusion capacity of neomycin A was shown to be different from that of neomycins B and C. Even minute admixtures of neomycin A in the preparations of neomycin significantly changes the dose-response curves and affected the results of the biological activity determination.

Diffusion↗
PubMed1983

[Basic principles of developing national standards for antibiotics].

The main principles in preparation of national standards of the antibiotics manufacture in the USSR are compared with those of the World Health Organization. The characteristics of preparing standards of mono- and multicomponent antibiotics, as well as the requirements for optimal packing of the standards are presented.

Anti-Bacterial Agents↗
PubMed1981

[Experience with the international standardization of the biological activity of the 3d Standard for streptomycin].

The activity of the third International Standard of streptomycin was determined to be equal to 755 IU/mg with the use of accurately weighed amounts of streptomycin and 78037 IU with the use of streptomycin ampoules. The Standardization Center of the WHO decided to use the whole content of the ampoule of the Third International Standard of streptomycin, the activity of which is determined to be equal to 78500 IU per an ampoule.

Bacillus cereus↗
PubMed1980

[Properties of tetracycline hydrochloride tablets and their bioavailability].

The properties of tetracycline hydrochloride tablets from various manufacturers were studied. Differences depending on the character of the coating were found: the film-coated tablets differed from dragee by a shorter period of the antibiotic transfer to solution, better disintegration, lower content of anhydroderivatives and higher stability. Correlation between the rate of tetracycline transfer to solution in vitro and the antibiotic absorption into blood on the oral use of the tablets was shown.

Biological Availability↗
PubMed1978

[Bioavailability of tetracycline hydrochloride capsules (an in vivo study)].

Blood absorption of tetracycline hydrochloride of various dispersity levels from capsules containing tetracycline alone or in combination with additives, such as magnesium carbonate and calcium salts was studied on humans. It was found that higher dispersity levels of tetracycline hydrochloride powder in capsules was not accompanied by increased blood absorption of the antibiotic. Addition of magnesium carbonate and calcium salts to the antibiotic in the process of capsulation markedly retarded the blood absorption. Clear correlation between the antibiotic dissolution rate in vitro and intensity of its blood absorption in volunteers was shown.

Adolescent↗
PubMed1978

[Effect of auxiliary substances on the bioavailability of tetracycline hydrochloride capsules (an in vitro study)].

The rate of tetracycline hydrochloride transfer into solution from capsules containing different auxiliary substances was studied. It was shown that the dispersity level of tetracycline hydrochloride powder had no significant effect on the capsule disintegration and the rate of the antibiotic transfer into solution. The effect of the auxiliary substance composition on the capsule disintegration and the rate of the antibiotic dissolution was shown. The rate of tetracycline liberation from the capsules containing tetracycline hydrochloride without additives or the antibiotic in combination with 23 per cent of lactose was 4 to 6 times higher than that from the capsules with magnesium carbonate or calcium phosphate as the auxiliary substances.

Biological Availability↗
PubMed1976

[Embryotoxicity and the immunodepressive action of tetracycline and its epi- and anhydro- derivatives].

The toxic effect of tetracycline and its epi- and anhydro-derivatives on growing chick embryos and the spleen cells of immunized mice was studied. High acute toxicity of 4-epianhydrotetracycline with respect to the chick embryos was found. Its LD50 was 4.8 times lower than toxicity of tetracycline hydrochloride. The characteristics of the acute toxicity was confirmed by the data on the embryo survival by the time of hatching. The same survival rate, i. e. 12 per cent was observed with the use of tetracycline and 4-epianhydrotetracycline in doses of 1000 and 100gamma per embryo respectively. Comparative investigation of the effect of tetracycline and anhydrotetracycline on the spleen cells revealed high toxicity of anhydrotetracycline which induced the same decrease in the number of the antibody-producing cells as tetracycline when used in doses 40 to 100 times lower than those of tetracycline. High toxicity of the anhydro-derivatives of tetracycline was also observed with respect to their teratogenic effect. Extremely pronounced anomalies in the embryo development were observed after exposure to 500gamma of 4-epianhydrotetracycline.

Animals↗
PubMed1976

[Differentiation of the degree of bioavailability of peroral drug forms of tetracycline hydrochloride in experiments on laboratory animals].

Difference in the levels of bioavailability of 4 types of tetracycline hydrochloride tablets was shown on rabbits and guinea pigs. The rates of the antibiotic absorption into the blood of the laboratory animals and volunteers were the same. Relation between the rate of disintegration of various types of tablets of tetracycline hydrochloride and the antibiotic blood levels in the rabbits after administration of the same tablets was found.

Administration, Oral↗
PubMed1975

[Biological and physicochemical properties of the alpha- and beta-forms of cephaloridine].

Alfa- and delta forms of cephalosporin were compared. Biological activity, lantimicrobial spectrum and innocuousness of the forms and their physico-chemical properties were investigated with the methods of infrared and ultraviolet spectrophotometry and derivatography. No significant differences in the biological properties of alfa- and delta forms of cephalosporin were found. However, the ingrared spectrum of the delta-form was indicative of higher stability of its molecule, which was confirmed by higher thermostability of delta-cephalosporin.

Animals↗