Unlike lactoperoxidase and horseradish peroxidase, thyroid peroxidase catalyzed the oxidation of hydroquinone mostly by way of 2-electron transfer. This conclusion could be derived from three independent experiments: ESR measurements of p-benzosemiquinone, trapping the unpaired electron by cytochrome c, and spectrophotometric analysis of catalytic intermediates of the enzymes. The 1-electron fl...

Background: Anti-thyroid peroxidase antibody (anti-TPO antibody) is a member of thyroid autoantibodies which are important in inducing and also diagnosing autoimmune thyroid diseases. Thyroid autoimmunity can cause several forms of thyroiditis and abnormal thyroid functions, ranging from hypothyroidism to hyperthyroidism. Objective: To evaluate the relationship between serum levels of anti-TPO ...

Endogenous peroxidase activity in rat thyroid follicular cells is demonstrated cytochemically. Following perfusion fixation of the thyroid gland, small blocks of tissue are incubated in a medium containing substrate for peroxidase, before being postfixed in osmium tetroxide, and processed for electron microscopy. Peroxidase activity is found in thyroid follicular cells in the following sites: (...

type i diabetes mellitus (dm) is frequently associated with autoimmune thyroid disease (atd). association of atd and type i dm has been described with varying frequencies but there is still debate about the situation in the iranian population. we investigated the prevalence of anti thyroid peroxidase (anti-tpo) antibodies and atd in children and adolescents with type i dm. a total of 145 patien...

Peroxidase activities of autonomously functioning thyroid tumors (T) and surrounding non-tumorous tissue (N) in 5 patients were determined by employing guaiacol or iodide as the second substrates. The mean values for specific activities of T were 30 times (in iodide oxidation assay) or 4 times (in guaiacol oxidation assay) as high as those in N, being significantly higher than those of non-func...

Crude thyroid peroxidase extracted from human thyroid microsomes was covalently bound onto polyacrylic and polyfunctional copolymerized microparticles. We observed agglutination of the thyroid peroxidase-microparticle conjugate with 13 monoclonal antibodies (mAbs) specific for epitopes on four different antigenic domains of human thyroid peroxidase (TPO; EC 1.11.1.7), after addition of anti-mou...

the host thyroid. The tumors themselves showed extremely low incorporation, although thyroidectomy of the host significantly increased the incorporation in the tumors. However, results of incorporation experiments do not distinguish the transitional from the autonomous tumors. Tumor growth also caused iodide peroxidase activity in the host thyroid to decline. The enzyme activity in the transiti...

Iodination within the thyroid follicle is intimately associated with a thyroid peroxidase. In order to locate the in vivo site of iodination, the initial cytochemical appearance of this enzyme has been determined in fetal rat thyroid and its presence correlated with the onset of iodinated thyroglobulin synthesis. Peroxidase first appears in follicular cells during the 18th day of gestation. It ...

BACKGROUND A case of congenital hypothyroidism with goiter (CHG) in a juvenile French bulldog was identified and hypothesized to be caused by dyshormonogenesis of genetic etiology. OBJECTIVES To describe case management, unusual phenotypic aspects, and a CHG-causing mutation in a French bulldog. ANIMALS Thyroid tissue and blood from a CHG-affected French bulldog and 4 normal control dogs an...

background: anti-thyroid peroxidase antibody (anti-tpo antibody) is a member of thyroid autoantibodies which are important in inducing and also diagnosing autoimmune thyroid diseases. thyroid autoimmunity can cause several forms of thyroiditis and abnormal thyroid functions, ranging from hypothyroidism to hyperthyroidism. objective: to evaluate the relationship between serum levels of anti-tpo ...