Tyroxine

Freiss G, Rochefort H, Vignon F (1990) Mechanisms of 4-hydroxytamoxifen antigrowth factor activity in breast cancer cells alterations of growth factor receptor binding sites and tyroxine kinase activity. Biochem Biophys Res Commun 919-926... 

Amino acids may be determined by measuring the amines obtained after the action of a carboxylase with a specific electrode for amines, which is based on a poly(vinyl chloride) membrane containing sodium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (166) as ion exchanger and tricresyl phosphate as solvent mediator. LOD was 20 and 50 i-M for tyroxine and phenylalanine, determined as tyramine (5) and phenethylamine (33), respectively364. 

Produces tyroxine and triiodothyronine hormones Adrenals Stress response, blood pressure, glucose metabolism, salt and water balance... 

In a double-blind trial, 500 j,g/day iodine orally or 0.125 mg/day L-tyroxine was given to 62 patients with ID (Kahaly et al., 1998). After 6 months, high Mic-Ab and Tg-Ab developed in 6 of the 31 patients receiving iodine compared to none in the tyroxine group. Fine needle biopsy revealed marked lymphocyte infiltration in all six antibody-positive subjects. After the withdrawal of iodine intake, antibody titer and lymphocyte infiltration decreased, and after 3 years, four of the six patients were again antibody negative. 

Ka, approximate association constant TBG, tyroxine-binding globulin TTR, transthyretin. 

In animals hormones are either formed de novo from substances of primary metabolism, e.g., steroid hormones, epinephrine, tyroxin, or they are synthesized from special secondary products which have to be taken up with the diet, e.g., unsaturated fatty acids (vitamins F) which are precursors of the eicosanoids. 

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