Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Iodine Compounds”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1992

Control of thyroid secretion: effects of stimulators of protein kinase C, thyrotropin, and calcium mobilization on secretion of iodinated compounds from sheep thyroid cells.

We have compared and contrasted the abilities of TSH and agents capable of discretely activating the cAMP-dependent protein kinase, protein kinase C, or calcium mobilization to influence the secretion of iodinated compounds from cells prelabeled with iodide and blocked from further organification with methimazole. We found that calcium mobilization induced by A23187, protein kinase C activation induced by 12-O-tetradecanoyl phorbol 13-acetate (TPA) and TSH all stimulated the secretion of iodinated compounds. The effects of TSH were mimicked by forskolin and those of TPA by a synthetic diacylglycerol, sn-1,2-dioctanoylglycerol. The effects of TPA were partially inhibited by staurosporine whereas those of TSH were not. Epidermal growth factor and norepinephrine were without effect on thyroid secretion. The effects of A23187 and TPA were synergistic. The effects of TSH and TPA were not and the increased secretion induced by either agent was partially prevented by the combination. Preincubation of cells with TSH desensitized the cells to further stimulation by TSH but the stimulatory effects of TPA were unaffected. Exposure of cells to medium without calcium also induced loss of iodinated compounds which was partially prevented by TSH or forskolin but not TPA. TSH did not stimulate the rapid production of inositol trisphosphate production. We conclude that the mechanisms by which TSH (through stimulation of cAMP) and stimulators of other intracellular pathways exert their effects on secretion of iodocompounds, differ. Activation of protein kinase C and acute production of inositol trisphosphate do not appear to be involved in the mechanism of action of TSH in stimulating thyroid secretion but calcium mobilization is implicated.

Alkaloids↗
PubMed1978

Chemical determination of iodinated compounds in human thyroid.

As a tool with which to detect iodinated compounds in human thyroid specimens, we have reevaluated a nonincineration technique which has so far been employed in the determination of thyroxine-iodine in peripheral blood. The catalytic action of iodoamino acids in the Ce-As reaction was enhanced by a small amount of Cl2. On the contrary, a large amount of Cl2 inhibited the reaction unexpectedly. Among iodide, iodotyrosine and iodothyronine, iodide was the most effective catalyst in the Ce-As reaction and iodothyronine was the least effective one. Protein seemed to inhibit this reaction of thyroglobulin. But the result of iodine content in thyroglobulin by this technique agreed well with that by incineration when measured 127I was corrected by percent activity of dializable part of the total activity of 131I-thyroglobulin with the same protein concentration, after the NaClO treatment. The results of human thyroid specimens were as follows: the thyroglobulin content of five normal subjects was 8.0 +/- 1.5% of wet thyroid weight. That of Hashimoto's disease was significantly decreased which seemed compatible with the decrease in iodine content of thyroglobulin, whereas thyroglobulin content of Graves disease treated with 1-methyl, 2-mercaptoimidazole followed by a large dose of iodide was well preserved in spite of a lower degree of iodination of thyroglobulin. As for the distribution of iodoamino acids-iodine in normal thyroid, T4 was 20.5 +/- 0.7%. This technique ultimately looks promising as a tool with which to study intrathyroidal iodine metabolism in human.

Adult↗
PubMed1984

Iodinated compounds and thyroxine binding to albumin in human breast milk.

Mature human milk samples from young healthy women on an equilibrated diet contained a mean of 81 ng/ml total iodine. Iodide represented a mean of 77% of the total iodine. Of the 22 ng/ml organic iodine, there was about 1 ng thyroxine and triiodothyronine and, after pepsin hydrolysis, up to 40% of organic iodine in monoiodotyrosine form. By electrophoresis, after incubation with radioactive thyroid hormone, we found an absence of binding on thyroxine-binding globulin, but thyroxine and triiodothyronine were bound to albumin with a maximal capacity 50 times higher than in human serum. All these differences did not favor transport of iodinated compounds from maternal serum to milk. In conclusion, milk iodide was taken up by newborn thyroid to make thyroid hormones.

Albumins↗
PubMed1990

[Measurements of 127I Mössbauer spectra for iodine compounds].

127I Mössbauer spectra of good quality were obtained at 20 K using a Zn127mTe source produced by high flux neutron irradiation of 66Zn-126Te at reactor core. The Mössbauer spectra for KI and some iodine(III) compounds with absorption intensity of about 5% suggest that the 127I Mössbauer spectroscopy is useful in elucidating the bonding nature of the iodine compounds. Preparative method of the Mössbauer source and experimental technique are reported in detail.

Iodine↗
PubMed1991

A method to quantitatively measure transcapillary transport of iodinated compounds in canine brain tumors with computed tomography.

We present a quantitative method for determining a blood-to-tissue influx constant (K1), a tissue-to-blood efflux constant (k2), and tissue plasma vascular space (Vp) that uses a computed tomographic (CT) scanner to make tissue and plasma measurements of the concentration of an iodinated compound. Meglumine iothalamate was infused intravenously over time periods of 0.5-5 min, up to 49 CT scans were obtained at one brain level, and arterial plasma was sampled over a 30- to 40-min period. K1, k2, and Vp were calculated for each voxel of the 320 x 320 matrix, using a two-compartment pharmacokinetic model and nonlinear least-squares regression. The method was used in dogs with avian sarcoma virus-induced brain tumors. As many as four studies on different days were done in the same animal. In tumor-free cortex, K1 of meglumine iothalamate was 2.4 +/- 1.7 microliter g-1 min-1 (mean +/- SD) and Vp was 3.4 +/- 0.5 ml 100 g-1. Mean whole-brain tumor K1 values ranged from 3.3 to 97.9 microliters g-1 min-1; k2 ranged from 0.032 to 0.27 min-1; and Vp ranged from 1.1 to 11.4 ml 100 g-1. These values were reproducible in serial experiments in single animals. Independent verification of K1 values was obtained with quantitative autoradiographic measurements of alpha-aminoisobutyric acid, which has similar physicochemical properties to meglumine iothalamate. The CT methodology is capable of demonstrating regional variation of transcapillary transport in brain tumors and may be of value in the study of human brain tumors.

Aminoisobutyric Acids↗
PubMed1989

[Efficacy of a PVP-iodine compound on selected pathogens of the oral cavity in vitro].

The study was designed to test the efficacy of a PVP-iodine antiseptic agent on potentially pathogenic oral bacteria. A 0.5% concentration of the test compound was sufficient to inhibit the growth of 7 out of 8 tested strains. Only bacteroides gingivalis continued to grow during exposure to a 0.5 and 1% concentration of the test compound. Quantitative suspension experiments demonstrated that the onset of action occurred within five minutes. Quantitative suspension experiments with protein loading resulted in a lower efficacy of the tested agent. Results indicate that the tested compound may be recommended as an oral disinfectant.

Bacteria↗