iodine /io·dine/ (I) (i´ah-dīn) chemical element, at. no. 53; it is essential in nutrition, being necessary for synthesis of the thyroid hormones thyroxine and triiodothyronine. Iodine solution is used as a topical antiinfective. See also radioiodine.
iodine (I)
iodine (īˑ·ō·dīn),
iodine (I) (ī´
dīn´),
protein-bound iodine iodine firmly bound to protein in the serum, determination of which constitutes one test of thyroid function.
i·o·dine (   -dn , -d n, -d n)n. 1. Symbol I A poisonous halogen element having compounds used as germicides, antiseptics, and food supplements, with numerous radioactive isotopes, which are used in diagnosis and treatment of thyroid diseases and neuroendocrine tumors. Atomic number 53. 2. A liquid containing iodine dissolved in ethyl alcohol, used as an antiseptic for wounds. |
iodine (I)
[ī′ədīn]
Etymology: Gk, ioeides, violet
a nonmetallic element of the halogen group. Its atomic number is 53; its atomic mass is 126.90. Iodine is a bluish black solid that becomes a violet vapor on heating without going through a liquid phase. Iodine is an essential micronutrient or trace element. Almost 80% of the iodine present in the body is in the thyroid gland, mostly in the form of thyroglobulin. Iodine deficiency can result in goiter or cretinism. Iodine is found in seafood, iodized salt, and some dairy products. It is used as a contrast agent for blood vessels in computed tomography scans. Radioisotopes of iodine are used in radioisotope scanning procedures and in palliative treatment of cancer of the thyroid.
iodine (īˑ·ō·dīn),
n an element/mineral used in the synthesis of thyroid hormones and whose deficiency is implicated in preventable mental retardation and brain maldevelopment. Iodine is present in kelp and seafood, with the most common supplemental source being iodized table salt.
iodine (I) (ī´
dīn´),n a halogen element that is nonmetallic in nature; atomic weight is 126.91. As a nutritional element, iodine is vital to the production of thyroxin by the thyroid gland. In radioactive form, iodine is used as a diagnostic substance to determine the ability of the thyroid gland to take up iodine. In tincture form, iodine is used as a locally applied antiseptic, germicide, and disclosing solution.
iodine number,
n the amount of iodine absorbable by 100 g of a fat or an oil; the lower the level of unsaturated fatty acids in the fat or oil, the higher the iodine number.
iodine, protein-bound (PBI),
n the iodine bound to protein, mainly thyroxin in the plasma. The thyroid hormone is precipitated by protein-denaturing agents, and, in general, the amount of iodine in a protein precipitate indicates the amount of thyroid hormone present and is thus an index of thyroid activity. Various values are given for thyroid function: hypothyroidism, 0 to 3.5 mg/ml of protein-bound iodine; euthyroidism, 3.5 to 8 mg/ml; hyperthyroidism, values higher than 8 mg/ml.
iodine
a chemical element, atomic number 53, atomic weight 126.904, symbol I. See Table 6. Iodine is essential in nutrition, being especially prevalent in the colloid of the thyroid gland. It is used in the treatment of hypothyroidism and as a topical antiseptic. Iodine is a frequent cause of poisoning. See also iodism.
iodine-125
a radioisotope of iodine having a half-life of 60 days and a principal gamma-ray photon energy of 28 keV; used as a label in radioimmunoassays and other in vitro tests, and also for thyroid imaging. Symbol 125I.
123iodine-metaiodobenzylguanidine
a radioisotope which concentrates in chromaffin cells; used in diagnostic scintigraphy, e.g. in cases of pheochromocytoma.
iodine-131
a radioisotope of iodine having a half-life of 8.1 days and a principal gamma-ray photon energy of 364 keV; used in treatment of hyperthyroidism and carcinoma of the thyroid, in thyroid function testing, and in imaging of the thyroid gland and other organs. Symbol 131I.
iodine deficiency
may occur in all species under certain conditions; in dogs and cats, a factor in all-meat diets. See also goiter.
iodine contrast agents
iodine salts are opaque to x-rays; therefore they can be combined with other compounds and used as contrast media in diagnostic x-ray examinations.
iodine nutritional deficiency
is characterized by goiter, neonatal mortality and alopecia.
iodine poisoning
occurs usually due to accidental overdosing. It causes lacrimation, anorexia, coughing due to bronchopneumonia, and a heavy dandruff. Paradoxically, iodine excess may result in thyroid hyperplasia and goiter, especially in the young.
protein-bound iodine
a test of thyroid function. See also protein-bound iodine (PBI) test.
radioactive iodine
see iodine-125, iodine-131 (above).
iodine residues in milk
careless use of iodine-based teat dips results in unacceptable residues of iodine in milk.
iodine solution
contains 2% free iodine and 2.4% sodium iodide in an aqueous solution.
iodine solution (strong)
contains 5% free iodine and 10% potassium iodide in an aqueous solution.
tamed iodine
see iodophor.
iodine trapping
the selective absorption of iodine from the circulation by the thyroid gland.
antiseptic
An agent that kills or prevents the growth of bacteria. This term is generally restricted to agents that are sufficiently non-toxic for superficial application to living tissues. These include the preservatives for eye drops and contact lens solutions. Examples of antiseptics are alcohol, benzalkonium chloride, cetrimide, chlorbutanol, chlorhexidine, hydrogen peroxide, thimerosal (or thiomersalate). Other agents that are too toxic to be applied to living tissues are called disinfectants and are used to sterilize instruments and apparatus. See disinfection; ethylenediamine tetraacetic acid; neutralization; sterilization.
How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content.
| ?Page tools | ||
|---|---|---|
|