Perchlorate competitively blocks iodide from entering the thyroid by an effect on the Na+/I- symporter thus preventing the further synthesis of thyroid hormone but has no effect on the iodination process itself. It is concentrated by thyroid tissue in a manner similar to iodide but is not significantly metabolized in the gland or peripherally. What is not settled is whether there are additional...

Iodine deficiency is a common phenomenon, threatening the whole global human population. Recommended daily intake of iodine is 150 μg for adults and 250 μg for pregnant and breastfeeding women. About 50% of human population can be at risk of moderate iodine deficiency. Due to this fact, increased iodine supplementation is recommended, through intake of iodized mineral water and salt iodization....

Iodine is an essential trace element for life. Iodide deficiency can lead to defective biosynthesis of thyroid hormones and is a major cause of hypothyroidism and mental retardation. Excess iodide intake, however, has been linked to different thyroidal diseases. How excess iodide causes harmful effects is not well understood. Here, we found that the nematode Caenorhabditis elegans exhibits deve...

609 samples of drinking water collected from scattered sources from the eight districts of Kandy, Matale, Kalutara, Anuradhapura, Polonnaruwa, Colombo,. Puttalam and Gampaha were analysed for iodide content using the Orion electrode method. The median iodide content of all districts except Gampaha were above 10 u g / 1 , with Anuradhapura showing the highest content. Districts with low prevalen...

Methyl iodide is a well-known volatile halogenated organic compound that contributes to the iodine content in the troposphere, potentially resulting in damage to the ozone layer. Most methyl iodide sources derive from biological activity in oceans and soils with very few abiotic mechanisms proposed in the literature. In this study we report that synthetic manganese oxide (birnessite δ-MnO2) can...

In porcine thyroid cells, thyroglobulin sulfation is controlled by thyrotropin (TSH) and iodide, which contribute to regulating the intracellular sulfate concentration, as we previously established. Here, we studied the transport of sulfate and its regulation by these two effectors. Kinetic studies were performed after [(35)S]sulfate was added to either the basal or apical medium of cell monola...

Perennial ryegrass (S23), timothy (S48), white clover (S100) and red clover (Hungaropoly), grown in culture solutions containing 0.2 x 5.0 x M-potassium iodide, showed relatively small differences in iodine uptake. The lowest uptake occurred with timothy, the species that also produced the lowest yields of dry matter. Red clover had the lowest concentration of iodine in the shoots on all treatm...

NVe studied the inhibitory effect of iodide on thyroid growtlk iR FRTL-5 cells, which pyeserve many thyroid functions, When the amount of iodide in medium exceeds IO-6 M, TSH-stimulated [3H]thymidine incorporation into DNA was sigRificantly inhibited. Methimazole (O.:5 mM> reversed the suppression, as was observed in other functions such as thyroid hormone synthesis and secretion. Cell numbers ...

A new carbon paste electrode (CPE) for the determination of iodide ion based on a cetyltrimethylammonium iodide (CTMAI) ion pair as an electroactive material is described. The electrode shows a linear response for iodide ion over the concentration range of 4 x 10(-5) M to 1 x 10(-1) M with a lower detection limit of 4 x 10(-5) M at 25 degrees C. The electrode has a Nemstian slope of -55.0 +/- 0...

Iodide absorption by fresh, summer Lam inaria digitata frond was accompanied b y about a fivefold increase in the rate o f oxygen consumption. Betw een approxim ately 3 and 6 m ole­ cules o f Oa were consumed for each iodide ion absorbed by the tissue and the respiratory quotient, whether measured in the presence or absence o f iodide, lay between 0*9 and 1*1 (mean 0*94). I t is argued th a t: ...