Type II deiodinase (D2) activates thyroid hormone by converting thyroxine (T4) to 3,5,3'-triiodothyronine (T3). This allows plasma T4 to signal a negative feedback loop that inhibits production of thyrotropin-releasing hormone (TRH) in the mediobasal hypothalamus (MBH) and thyroid-stimulating hormone (TSH) in the pituitary. To determine the relative contributions of these D2 pathways in the fee...

Objective : The present study was designed to investigate variations in the levels of thyroid hormones (T3, T4) in breast and ovarian cancers patients. Methods : A total 120 subjects were recruited (without thyroid history) divided into three groups; A, B and C. Group A as control with healthy individuals. While group B and group C were consisting of breast cancer and ovarian cancer patient res...

INTRODUCTION Video-assisted thoracic sympathectomy (VATS) is one minimally invasive definitive treatment for axillary hyperhidrosis. Different techniques exist for controlling axillary sudoresis, but they are temporary and have high cost. This study was conducted to compare the initial results from sympathectomy using two distinct levels for treating axillary sudoresis: T3-T4 vs T4. METHODS S...

In a previous study of a representative population of 460 men of age 70, we found that the free thyroxin (free T4) concentration was negatively correlated to body mass. In the present study we analyzed other indicators of thyroid function in relation to body mass and body mass index in 181 individuals without any disease or medication influencing thyroidal homeostasis or body mass. There was a ...

We report an anesthetic experience in a clinically euthyroid patient with hyperthyroxinemia (elevated free thyroxine, fT4 and normal 3, 5, 3'-L-triiodothyronine, T3) and suspected impairment of conversion from T4 to T3. Despite marked hyperthyroxinemia, this patient's perioperative hemodynamic profile was suspected to be the result of hypothyroidism, in reference to the presence of T4 to T3 con...

Although hypercalcemia, osteoporosis, and increased bone turnover are associated with thyrotoxicosis, no direct effects of thyroid hormones on bone metabolism have been reported previously in organ culture. We have now demonstrated that prolonged treatment with thyroxine (T4) or triiodothyronine (T3) can directly increase bone resorption in cultured fetal rat long bones as measured by the relea...

Effects of short-term administration of corticosterone and cortisol on plasma levels of thyroid hormones, gonado-somatic index and testicular histology have been reported in catfish, Clarias gariepinus during different phases of its breeding cycle. Corticosterone administration had no significant effect on plasma levels of T4, T3 and T3/T4 ratio, irrespective of doses and phases of breeding cyc...

This study evaluated the morphological changes in the temporomandibular joint (TMJ) condyles and calculated the Helkimo clinical dysfunction index (CDI) in adolescents with Class II Division 1 malocclusion and mandibular retrognathism treated with the Herbst appliance (phase I) and fixed orthodontic appliances (phase II). Thirty-two consecutive adolescents underwent phase I, and 23 completed ph...

BACKGROUND Thyroid is one of the ductless endocrine gland, which is located immediately below the larynx on either side of and anterior to the trachea. The principal hormones of thyroid gland are thyroxine (T4) and triiodothyronine (T3). The current study was carried out to investigate the impact of race, gender and area on the levels of Thyroxine (T4), Triiodothyronine (T3) and Thyroid Stimula...