When concentrations of free thyroid hormones in serum are measured by equilibrium dialysis, the serum sample is diluted by dialysis buffer, resulting in a new equilibrium for distribution of these hormones that differs from that in the original serum sample. We have derived a mathematical formulation, based on an equilibrium model for multiple ligands and multiple binding sites, to determine th...

Changes in TSH secretion in six acromegalic patients were studied before and after transsphenoidal adenomectomy (Hardy's method) and compared to normal subjects and six patients with prolactinoma. Basal serum GH levels ranging from 5 to over 250 ng/ml before adenomectomy decreased to below 5 ng/ml after the operation, and the abnormal responses of GH to TRH observed initially in three of the si...

OBJECTIVE Deposits of myxoid material, similar to myxedema related to thyroid disease, are described in the medial layer of aortas with dissection. We analyzed the clinical or subclinical thyroid dysfunction of patients with this disease and analyzed whether a correlation exists between serum levels of thyroid-related hormones and the myxoid content of the aortic media. METHODS We measured, w...

OBJECTIVE To characterize thyroid disturbances induced by interferon-alpha and ribavirin therapy in patients with chronic hepatitis C. INTRODUCTION Interferon-alpha is used to treat chronic hepatitis C infections. This compound commonly induces both autoimmune and non-autoimmune thyroiditis. METHODS We prospectively selected 26 patients with chronic hepatitis C infections. Clinical examinat...

Because little has been published on early effects of treatment with amiodarone on thyroid function, we studied serum total and free thyroid hormone, reverse T3, and TSH levels in patients with cardiac arrhythmias during the first 10 days of treatment with a loading dose of amiodarone by iv infusion. Twenty-four patients were enrolled in the study. A standardized loading regimen for the i.v. in...

TSH secretion is decreased by both T4 and T3. This negative feedback control ofTSH secretion has been correlated with an increase in pituitary nuclear T3 content, and it is not clear whether T4 exerts its effect directly on the thyrotroph or after its deiodination to T3. However, levels of the pituitary enzyme catalyzing T4 to T3 conversion, 51)-II, are decreased in the presence of an increased...

In the past decade, emphasis has shifted from testing of thyroid function in individuals who are likely to have a thyroid disorder to a broader population, an approach that identifies so-called subclinical thyroid dysfunction in up to 10% of women over fifty. The key assays that are used to detect thyroid dysfunction are serum thyroid stimulating hormone (TSH) and the main circulating thyroid h...

The main objective of this study was to characterize nuclear T3 and T4 binding in the developing rat brain. More specifically, we sought to determine (a) whether T3 and T4 bind to the same nuclear receptor, (b) whether there are multiple forms of nuclear T3 or T4 receptors, and (c) whether the above parameters are similar in nuclei of cerebral hemispheres and cerebellum of developing rat brain....