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Biomedical subjects

R D Barabash

Publications and source records attributed to R D Barabash.

At least 37 records · Page 2Linked to original sources
PubMedDate not supplied

[Enzymatic mechanisms for antimicrobial protection of the oral cavity].

Data on the role of oral lysozyme, ribonuclease, deoxyribonuclease and peroxidase in antimicrobial defense of the macroorganism are reviewed. The biochemical and physiological properties of the enzymes secreted by salivary glands and released from emigrating leukocytes are discussed. Spectra of antimicrobial action of the enzymes and participation of these enzymes in maintaining the stability of oral biocenosis are described as well as the regulation of these enzymatic activities and the pathogenetic significance of impairments in their secretion. The most perspective aspects of the problems discussed are outlined for further investigation.

Animals↗
PubMedDate not supplied

[The pharmacokinetics of hematoporphyrin, its derivative and fluorescein during the development of carcinosarcoma].

The pharmacokinetics of fluorescein, hematoporphyrin and a derivative of hematoporphyrin was studied microspectrofluorometrically on rats with transplanted carcinosarcoma. It was shown that in the rats in contrast to intact animals the tissue concentration of fluorescein exhibits a general tendency towards an increase, that of hematoporphyrin towards a decrease and that of hematoporphyrin derivative towards an increase in all parenchymatous organs and a decrease in the skin and mucosae of the hollow organs. At the equally short period of the maximal accumulation of luminophores, the tumour tissue differs from the normal one by a pronounced delay of excretion only of hematoporphyrin derivative.

Animals↗
PubMedDate not supplied

[The pharmacokinetics of fluorescein, hematoporphyrin and its derivative during the development of granuloma].

In experiments on rats with granuloma reproduced by subcutaneous implantation of foreign material there was shown a slowing of excretion from the organism as well as a considerable redistribution between the organs of fluorescein, hematoporphyrin and its derivative as compared with intact animals. The noted changes practically did not depend on the time of granuloma development.

Animals↗
PubMedDate not supplied

[Various features of peroxidase in human saliva].

Optimal conditions are determined for isolation and purification of peroxidase (EC 1.11.1.7) from the mixed human saliva by gel-filtration and ion chromatography. Such properties as pH and temperature optima, molecular weight, Km, amino acid composition, the effect of activators and inhibitors (purified saliva peroxidases and commercial preparation of horse-radish peroxidase "Reanal", Hungary) are studied with the use of different substrates. The data obtained are necessary to optimize production processes of isolation, storage and methods of the experimental and clinical application of peroxidases of different origin.

Amino Acids↗
PubMedDate not supplied

[Isolation and properties of 2 kallikreins from human saliva].

Two kallikreins (K-I and K-II) were purified from mixed, parotid and submandibular human saliva. The kallikreins were separated by chromatography on CM-cellulose. The pH optima of activity were at pH 9.3 and pH 9.6-9.8; Km for BAEE was 1.10-3M and 4.10-3M, respectively. The esterase activity of K-I and K-II was inhibited by trasylol-like inhibitors, while the plant and synthetic inhibitors of trypsin were uneffective. In dog, rabbit and rat the hypotensive effect of K-II and its action upon the permeability of rabbit skin was 4-5 fold higher than the effects of K-I. Ki and K-II did not alter the arterial blood pressure in guinea pig.

Animals↗
PubMedDate not supplied

[Method for determining peroxidase activity].

The spectrophotometric method is described for the peroxidase activity determination which is based on the oxidation of guaicol and potassium iodide. Optimal conditions were elaborated for these two most sensitive substrates. The method may be applied for the quantitative peroxidase determination in different human biological fluids, in particular saliva and blood serum.

Guaiacol↗
PubMedDate not supplied

[Role of peroxidase in the pathogenesis of parodontosis].

In order to study the role of peroxidase in pathogenesis of periodontosis clinical observations were carried out in 132 patients with inflammatory-dystrophic form of periodontal disease and eight species of laboratory and domestic animals were used in experiments. In the patients studied a distinct increase in peroxidase activity was observed in mixed saliva and in gum tissues, which correlated with the severity of the periodontal disease. Inflammatory-dystrophic impairment of cat periodontium was accompanied by an increase in the peroxidase activity only in gum and alveolar process tissues; cats are characterized by the highest amounts of exogenous peroxidase in oral tissues as compared with other laboratory animals. High amounts of exogenous peroxidase did not affect the periododontal tissues of rats during long-term experiments. The main protective effects of the enzyme were as follows: bacteriostatic influence on streptococci in oral cavity and inhibition of leukocyte emifration. Estimation of the peroxidase activity in saliva may be considered as a diagnostic test for periodontosis and may be used to monitore the course of treatment.

Adult↗