Thyroidal function

Selenium is an essential element and is beneficial at low concentrations, serving as an antioxidant. Lack of selenium affects thyroid function, and selenium deficiencies have been linked to Keshan Disease (34). Selenium at high levels, however, is toxic. Hydrogen selenide (which is used in semiconductor manufacturing) is extremely toxic, affecting the mucous membranes and respiratory system. However, the toxicity of most organ oselenium compounds used as donor compounds for organic semiconductors is not weU studied. 

Thyroid-stimulating hormone can be used clinically to test thyroid function but has not found practical apphcation in the treatment of human thyroid insufficiency. Direct replacement therapy with thyroid hormone is easy and effective, owing to a simple molecular stmcture. TSH has been used in the veterinary treatment of hypothyroidism, and preparations of TSH ate produced by Cooper Animal Health, Inc. and Armour Pharmaceuticals. 

Iodine. Of the 10—20 mg of iodine in the adult body, 70—80 wt % is in the thyroid gland (see Thyroid and antithyroid preparations). The essentiahty of iodine, present in all tissues, depends solely on utilisation by the thyroid gland to produce thyroxine [51-48-9] and related compounds. Well-known consequences of faulty thyroid function are hypothyroidism, hyperthyroidism, and goiter. Dietary iodine is obtained from eating seafoods and kelp and from using iodized salt. 

Health and Safety Factors. Phloroglucinol has low toxicity by ingestion. Prolonged severe overexposure may dismpt the thyroid function. High dust concentration may cause respiratory irritation the product is irritating to eyes and skin. Toxicity data include LD q oral (rat) = 5800 mg/kg ... 

The only commonly used radioisotope in this class is used in small (- IS.S MBq (500 -lCi) injected dose) quantities as a diagnostic for the evaluation of thyroid function. The compound is adininistered as Nal and these procedures are only possible owing to the favorable biological distribution of iodide. Up to 25% of the entire injected dose of iodide is accumulated in the thyroid with a very slow washout the rest is rapidly excreted in the urine. No other compound exhibits so high a ratio of concentration in a target tissue to that of other tissues. 

Body fluids are analyzed for T and T by a variety of radioimmunoassay procedures (31) (see Immunoassays). The important clinical parameter for estimating thyroid function, the protein-bound iodine (PBI), is measured as described in treatises of clinical chemistry. High performance Hquid chromatographic (hplc) methods have replaced dc (32,33). 

Potassium Iodide. When potassium iodide [7681-11-0] is adrninistered orally for several (6—8) weeks, a therapeutic effect may be obtained ia the subcutaneous form of sporotrichosis. Amphotericin B is used iatravenously to treat systemic sporotrichosis. The KI dosage is usually a saturated solution ia water (1 g/mL). The usual oral dose is 30 mg/kg/d. Children should receive five droplets, three times a day (after meals) the dose may be iacreased to 15—20 droplets. Side effects iaclude digestive disorders, swelling of the saUvary glands, and lacrimation. Thyroid function tests may be disturbed. 

Disruption of thyroid functions in vertebrates has been suggested to constitute a potential threat to many vital functions. For example, there is a possibility that disruption to the thyroid hormone levels during embryogenesis could result in disturbed behaviour patterns in the adult form, possibly interfering with migration in certain species and sonar functions in cetaceans. In anurans, thyroid hormones are essential for initiating metamorphosis. ... 

Evidence for chemically mediated disruption of thyroid function in wild reptile populations includes the finding of elevated thyroxine levels in male alligators from Lake Apopka, although a causal relationship with specific chemicals has not been established. ... 

Iodoquinol is contraindicated in patients with known hypersensitivity. Iodoquinol is used with caution in patients with thyroid disease and during pregnancy and lactation. Iodoquinol may interfere with the results of thyroid function tests. This interference not only occurs during therapy, but may last as long as 6 months after iodoquinol therapy is discontinued. 

No significant interactions have been reported when tiie expectorants are used as directed. The exception is iodine products. Lithium and other antithyroid drug may potentiate the hypotliyroid effects of these drug if used concurrently with iodine products. When potassium-containing medications and potassium-sparing diuretics are administered with iodine products, the patient may experience hypokalemia, cardiac arrhythmias, or cardiac arrest. Thyroid function tests may also be altered by iodine... 

Periodic testing of growth hormone levels, glucose tolerance, and thyroid functioning may be done at intervals during treatment. 

Boas, M., Feldt-Rasmussen, U., and Skakkebaek, N.E. et al. (2006). Environmental chemicals and thyroid function. European Journal of Endocrinology 154, 599-611. 

The health effects of phytoestrogens osteoporosis, cardiovascular disease and thyroid function... 

VAN WYK J J, ARNOLD M B, WYNN J, PEPPER F (1959) The effects of a soybean product on thyroid function in humans. Pediatrics. 752-60. 

Mayne GJ, Bishop CA, Martin PA, Boermans UJ, Hunter B. 2005. Thyroid function in nestling tree swallows and eastern bluebirds exposed to non-persistent pesticides and p, p -DDE in apple orchards of southern Ontario, Canada. Ecotoxicology 14 381-396. 

D. Coomans, I. Broeckaert, M. Jonckheer and D.L. Massart, Comparison of multivariate discrimination techniques for clinical data—Application to the thyroid functional state. Meth. Inform. Med., 22 (1983) 93-101. 

Assess possible correctable etiologies, including myocardial ischemia, serum potassium concentration (for hyperkalemia), and thyroid function tests (for hypothyroidism). 

Thyroid function tests abnormal thyroid hormone levels may suggest hypo- or hyperthyroidism, either of which may be associated with constipation. 

Approximately 80% of patients with a GFR less than 20 to 30 mL/minute develop metabolic acidosis.38 Metabolic acidosis can increase protein catabolism and decrease albumin synthesis, which promote muscle wasting, and alter bone metabolism. Other consequences associated with metabolic acidosis in CKD include worsening cardiac disease, impaired glucose tolerance, altered growth hormone and thyroid function, and inflammation.38... 

Criteria for diagnosis Five or more attacks fulfilling the above criteria are necessary for diagnosis Laboratory assessments that may be helpful in excluding medical comorbidities Complete blood cell count (CBC), chemistry panel, thyroid function tests, erythrocyte sedimentation rate (ESR)... 

Tests to exclude possible causes of dementia include a depression screen, vitamin B12 deficiency, thyroid function tests [thyroid-stimulating hormone (TSH) and free triiodothyronine and thyroxine], complete blood cell count, and chemistry panel.21... 

Perform urinalysis, urine toxicology, thyroid function, and white blood cell count in the elderly to rule out urinary tract infection... 

Basic laboratory tests complete blood count, blood chemistry screen, thyroid function, urinalysis, urine drug screen... 

Exam General Chemistry 3 Hematologic Tests" Metabolic Tests6 Liver Function Tests Renal Function Tests Thyroid Function Tests Serum Electrolytes Dermatologic6 ... 

IVday, monitor urinalysis, osmolality, and specific gravity every 3 months. Thyroid function tests should be obtained once or twice during the first 6 months, then every 6-12 months monitor for signs and symptoms of hypothyroidism if supplemental thyroid therapy is required, monitor thyroid function tests and adjust thyroid dose every 1-2 months until thyroid function indices are within normal range, then monitor every 3-6 months. 

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