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Biomedical subjects

T A Babaev

Publications and source records attributed to T A Babaev.

At least 19 recordsLinked to original sources
PubMed1992

[Role of immune complexes in thyroid diseases].

To elucidate the immune complex (thyroglobulin-antibody, Tg-Ab) role in thyroid hormone formation, in vitro iodination of Tg--AB immune complex, bovine intact Tg and that of the patient with euthyroid goiter and partially purified AB to Tg were studied. We compared the amount of iodamine acids (MIT, DIT, T4/mole of Tg) forming during iodination in immune complex with other samples. The results suggest that Tg being in complex with antibodies (up to 30-40 mole of antibodies/mole of Tg) is iodinated forming the enough amount of MIT, decreased amount of DIT and T4. A MIT fraction increase is connected with additional iodination of complex antibodies. We suggest that such processes may take place in the patient body and be involved in pathogenesis of thyroid disease.

Animals↗
PubMed1983

[The role of thyroglobulin carbohydrates in its hormone-liberating function. Proteolysis of deglycosylated thyroglobulin].

The proteolysis of thyroglobulin was performed after partial cleavage of its carbohydrate moiety. It was demonstrated that enzymatic removal of some thyroglobulin sialic acids results in increasing its resistance to proteolysis. Apparently, sialic acids are essential for maintaining an optimal thyroglobulin conformation for the action of proteases at hormonal biosynthesis from the reserve form.

Animals↗
PubMed1982

[Condensation of residues of diiodotyrosine with thyroxine near the surface of the thyroglobulin molecule by means of differential spectrophotometry].

Aromatic amino acids including iodotyrosines and thyroxin in intact, extraiodinated and acetylated bovine thyroglobulin were studied by the differential spectrophotometric technique. Modifications (i. e. acetylation, iodination) changed the accessibility of these chromophores to ethylene glycol. The data obtained suggest that thyroxin can be formed from two diiodotyrosine residues in the surface regions of the thyroglobulin molecule which are available for ethylene glycol.

Animals↗
PubMed1980

Differential spectrophotometry of iodoamino acids and iodinated proteins. Aqueous ethylene glycol solutions of iodotyrosines, thyroxine and thyroglobulin.

Solvent perturbation difference spectra and corresponding molar extinction coefficients of solutions of monoiodotyrosine, diiodotyrosine and thyroxine with protonated and deprotonated hydroxyls were measured with 20% ethylene glycol as perturbant. Data obtained were applicable to the development of the method of quantitative estimation of the number of iodotyrosine and thyroxine residues accessible to ethylene glycol in iodinated proteins. This method was used for the determination of iodoamino acids available to ethylene glycol in bovine thyroglobulin (naturally iodinated protein).

Animals↗
PubMed1980

[Extinction coefficient of thyroglobulin].

The extinction coefficient at 280 nm of the solution (pH 7,2-7,4) of thyroglobulin from normal thyroid and nodular euthyroid goiter was measured with the values of 0,6-0,7 to 0,9 ml.mg-1.cm-1. The value of E1%280 as function of the iodoamino acid content depends on the morphological state of the thyroid gland. A simple method for determination of the E1%280 value by measuring of the protein absorption spectrum is proposed.

Amino Acids↗
PubMed1976

[14C-1-Tyrosine metabolism on rat thyroid gland].

Amino acid composition of incubation medium, thyroid tissue hydrolysate and purified thyreoglobulin (Tr) preparations, isolated after 5 hour incubation with 14C-1-tyrosine in Jey medium is studied by means of electrophoresis and autoradiography. 5 radioactivity stains are detected on radioelectrophoregram of incubation medium, 2 of them corresponding to tyrosine and serine. 2 stains corresponding to diiodotyrosine and triiodotyronine are found in hydrolysate of thyroid tissue. No radioactive stains were found on radioelectrophoregrams of thyreoglobulin. The data obtained indicate that in the reaction of condensation of iodotyrosines into iodotyronine a lateral chain of iodotyrosine (serine) splits off. Thyroid hormones biosyntesis takes place by condensation of either a single free molecule of iodotyrosine with iodotyrosyl residue of polypeptide chain of pre-synthesized thyreoglobulin, or two free molecules of iodotyrosine.

Amino Acids↗
PubMed1976

[Synthesis of iodoamino acids during in vitro thyroglobulin iodination in different states of its molecule].

Iodotyrosine and iodothyronine residues are formed in the protein molecule during bovine thyroglobulin iodination in vitro. Dissociation and reassociation of the thyroglobulin molecule have no significant influence on its iodoaminoacid composition. Thyroglobulin iodination in the presence of 8 M urea does not result in thyroxine synthesis despite the increased formation of iodotyrosine residues. Similarly, during iodination of reassociated thyroglobulin the new molecules of thyroxine are not formed either. It is presumed that during reassociation of thyroglobulin subunits the native conformation of the protein is not completely reconstituted. The results obtained suggest that the structure of thyroglobulin controls the distribution of the iodine atoms incorporated by the iodoaminoacid residues.

Animals↗
PubMedDate not supplied

[Features of treating patients with combined damage to the orbit and eye in the late period in peacetime and war conditions].

Analysing the diagnosis and treatment of 100 patients with combined injuries of the organ of vision and orbital zone of the face provided clinical features of lesions in peace-time or battle accidents. Battle accidents were found to be prognostically worse for visual functions. The use of immunotherapy for inflammatory complications of a traumatic process is demonstrated to be advisable. A program of stepwise treatment of combined lesions of the eye and the orbit with the priority of preserving the function of the vision organ. At stage 1 it is necessary to take measures for restoration of visual functions to avoid their decline or loss. At stage 2 reconstructive interventions in the orbit and visceral cranium, directed to the provision of topographic and trophic conditions for further restoration of eye functions should be performed. One-stage surgical intervention may be used if there are no real danger of vision loss. The peculiarities of reconstructive treatment of multifractional fractures of the orbit in the battle accident and fragmental fractures of the orbit in peace-time accident are described. Patients with combined injuries of the vision organ and the orbit in specialized institutions should be cared.

Adolescent↗
PubMedDate not supplied

[Membrane activity of a cell-free filtrate of Shigella flexneri 2a].

In the course of metabolism in Shigella Flexneri 2A strain there was noted secretion of a membrane-tropic factor into media. This factor increased the conductivity of bilayer lipid membranes causing formation of ionic channels in them. Minimal conductivity of the channels was about 25 pS in 0.5 M NaCl; at PH 7-8 the channels exhibited cation-anion selectivity. The calculated number of cation transfer (T+) was elevated with an increase in the channel amplitude, approaching 0.86. Since the conductivity of the channels depended on the definite potential, the component studied appears to have an intracellular localization under normal conditions; possible mechanism of its liberation into surrounding medium is discussed.

Animals↗
PubMedDate not supplied

[Isolation of thyroglobulin from the bovine thyroid free of endogenous proteolytic activity].

Thyroglobulin was isolated from the cattle thyroid gland by chromatography on Sephadex G-200 and Sepharose 4B. It was found homogeneous according to disc electrophoresis (pH 8.6) and analytical ultracentrifugation. However, gel filtration of thyroglobulin incubated at 37 degrees through Sepharose 6B revealed that it contained proteinases of the serine type. The conditions for the proteinases' inhibition were found. The possibility of obtaining thyroglobulin free of the proteinases by means of affinity chromatography is demonstrated.

Animals↗