Iodine

About: Iodine is a research topic. Over the lifetime, 8936 publications have been published within this topic receiving 139981 citations. The topic is also known as: I & element 53.

Effects of selenium and iodine deficiency on thyroid hormone concentrations in the central nervous system of the rat.

Abstract: Objective: The effects of single and combined nutritional selenium and iodine deficiency on intracellular thyroid hormone concentrations and type II 5'-iodothyronine deiodinase (5'D-II) activity were examined in different regions of the adult rat brain. Design: Four groups (n=6) of weanling female Wistar rats proceeding from a breeding line fed a selenium-deficient or a selenium-replete diet for 3 generations, were fed selenium-deficient, iodine-deficient, combined selenium- and iodine-deficient or selenium- and iodine-replete diets for 2 months before they were killed. Methods: Tissue thyroxine (T 4 ) and tri-iodothyronine (T 3 ) concentrations were determined by highly sensitive RIAs after extraction of the iodothyronines from the tissue samples. The measurement of 5'D-II was based on the release of radioiodide from the 125 I-labelled substrate. Results: Selenium deficiency significantly decreased tissue T 3 concentrations in the hippocampus, hypothalamus and striatum to 70-80% of controls, whereas no significant changes were found in the cerebellum, cerebral cortex and brain stem. Tissue T 4 concentrations were only marginally affected with the exception of a 35%, increase in the cerebral cortex. Iodine deficiency dramatically diminished serum T 4 levels as well as intracellular T 4 concentrations in all regions examined up to 10-30% of control. In spite of a threefold enhancement of 5'D-II,the iodine-deficient animals still had a significant reduction of tissue T 3 concentrations (50-65% of controls) in all regions excepting the cerebellum. The combination of selenium and iodine deficiency did not significantly alter this pattern of changes. Conclusions: These findings suggest that prolonged selenium deficiency as well as iodine deficiency may compromise thyroid hormone homeostasis in the adult brain leading to tissue hypothyroidism and therefore to impaired brain function.

Evaluation of iodine nutritional status in Tehran, Iran: iodine deficiency within iodine sufficiency.

Abstract: Background: Production of iodized salt in Iran for household consumption began in 1990. Previous studies have reported sustainable elimination of iodine deficiency disorders in Iran. The aim of this study was to evaluate the iodine nutritional status in Tehran in 2009. Methods: In this cross-sectional study, 383 Tehranian households were enrolled through randomized cluster sampling and a total of 639 adult subjects (242 men and 397 women), aged 19 and over, participated. A 24-hour urine sample was collected for measurement of urinary iodine, sodium, and creatinine concentrations using the digestion method, flame photometry, and autoanalyzer assay, respectively. Salt intake was estimated and iodine content of household salt was measured by titration. Results: Median (interquartile range) iodine content of household salt and urinary iodine concentration (UIC) in Tehran were 21.2 (3.2–31.7) parts per million and 70.0 (34.0–131.2) μg/L, respectively. There was no statistically significant difference in 24-hou...

Novel and efficient synthesis of 1-iodoalkynes

Abstract: Treatment of terminal alkynes with (diacetoxyiodo)benzene, potassium iodide, and copper(I) iodide afforded 1-iodo-alkynes in good to excellent yields under mild conditions.