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Byline: Jugal. Gada, Prudwiraj. Sanamandra, Sagar. Barasara, Yash. Chauhan, Nikhil. Bhagwat Functioning pituitary tumors contribute to significant morbidity and mortality. Proper diagnostic approach and management is essential for optimal outcomes. [...]

The case of a 13-year-old girl with an enlarging neck mass is discussed to arrive at a better understanding of papillary thyroid carcinoma, diffuse sclerosing variant, associated with chronic autoimmune throiditis. The different treatment methodologies and management regime for the same are highlighted.

The study aims to evaluate the relationship if any between subclinical hypothyroidism and the risk of coronary heart disease (CHD) and mortality. The results indicate that an association does exist between the two.

Perchlorate blocks thyroidal iodide transport in a dose-dependent manner. The human sodium/iodide symporter (NIS) has a 30-fold higher affinity for perchlorate than for iodide. However, active transport of perchlorate into thyroid cells has not previously been demonstrated by direct measurement techniques. To demonstrate intracellular perchlorate accumulation, we incubated NIS-expressing FRTL-5 rat thyroid cells in various concentrations of perchlorate, and we used a sensitive ion chromatography tandem mass spectrometry method to measure perchlorate accumulation in the cells. Perchlorate caused a dose-related inhibition of 125-iodide uptake at 1-10 [micro]M. The perchlorate content from cell lysate was analyzed, showing a higher amount of perchlorate in cells that were incubated in medium with higher perchlorate concentration. Thyroid-stimulating hormone increased perchlorate uptake in a dose-related manner, thus supporting the hypothesis that perchlorate is actively transported into thyroid cells. Incubation with nonradiolabeled iodide led to a dose-related reduction of intracellular accumulation of perchlorate. To determine potential toxicity of perchlorate, the cells were incubated in 1 nM to 100 [micro]M perchlorate and cell proliferation was measured. Even the highest concentration of perchlorate (100 [micro]M) did not inhibit cell proliferation after 72 h of incubation. In conclusion, perchlorate is actively transported into thyroid cells and does not inhibit cell proliferation. iodide; [Na.sup.+]/[I.sup.-] symporter

BACKGROUND: Disruption of thyroid homeostasis has been indicated in human studies targeting effects of persistent organic pollutants (POPs). Influence on the maternal thyroid system by POPs is of special interest during pregnancy because such effects could impair infant thyroid homeostasis. OBJECTIVES: We investigated the association between POPs and thyroid-stimulating hormone (TSH) and thyroid hormones (THs) in mother and child pairs from the Northern Norway Motherand-Child Contaminant Cohort Study (MISA). METHODS: Nineteen POPs and 10 thyroid parameters were analyzed in serum from 391 pregnant women in their second trimester. In addition, TSH concentrations in heel-prick samples from the infants were analyzed by the Norwegian Newborn Screening program. Association studies with a multipollutant approach were performed using multivariate analyses; partial least squares (PLS) regression, hierarchical clustering, and principal component analysis (PCA). RESULTS: Several POPs were significantly associated with TSH and THs: a) PFOS was positively associated with TSH; b) PCBs, HCB, and nonachlors were inversely associated with [T.sub.3], [T.sub.4], and F[T.sub.4]; and, c) PFDA and PFUnDA were inversely associated with [T.sub.3] and F[T.sub.3]. After mutual adjustments for the other contaminants, only PFDA and PFUnDA remained significantly associated with [T.sub.3] and F[T.sub.3], respectively. Infants born to mothers within the highest TSH quartile had 10% higher mean concentrations of TSH compared with children born to mothers in the lowest TSH quartile. CONCLUSION: The present results suggest that background exposures to POPs can alter maternal thyroid homeostasis. This research contributes to the understanding of multipollutant exposures using multivariate statistical approaches and highlights the complexity of investigating environmental concentrations and mixtures in regard to maternal and infant thyroid function. http://dx.doi.org/10.1289/EHP152, Introduction Human endocrine systems such as the thyroid are susceptible to disruption by naturally occurring and human-made compounds, possibly by affecting the hormone homeostasis. Endocrine-disrupting abilities have been suggested for [...]

Introduction: Although it has been established that hyperthyroidism leads to reduced bone mineral density (BMD), with accelerated bone turnover promoting bone resorption in female patients, there is a dearth of data for male patients with hyperthyroidism. This study evaluated BMD and bone metabolism in male patients with Graves' disease. Methods: The study included 56 Japanese male patients with newly diagnosed Graves' disease and 34 normal Japanese male control subjects of similar age and body mass index. We used dual energy x-ray absorptiometry to measure BMD at sites with different cortical/cancellous bone ratios (lumbar spine, femoral neck, and distal radius). Results: At the lumbar spine and the distal radius, BMD and T-scores were significantly lower for patients than for controls. At the femoral neck, on the other hand, the same values were relatively, but not significantly, lower in patients than in controls. However, Z-scores at all three sites were significantly lower for patients than for controls. The Z -score at the distal radius of patients was significantly lower than that at their lumbar spine and femoral neck. In addition, Z-score at the distal radius correlated negatively with age, free thyroxine, thyroid stimulating hormone receptor antibodies, thyroid stimulating antibody, and urinary N-terminal telopeptide of type I collagen normalized by creatinine. Conclusions: These results indicate a high prevalence of cortical bone loss in male patients with Graves' disease, especially elderly patients. We conclude that BMD measurement is crucial in all Graves' disease patients regardless of their gender and that the radial BMD as well as BMD at the lumbar spine and femoral neck should be monitored to effectively prevent bone loss and subsequent fracture. Keywords Bone mineral density * Distal radius * Graves' disease * Male patients * TSH receptor antibodies

A low concentration of the thyroid hormone thyrotropin in the blood of persons aged 60 or older may be an independent risk factor for atrial fibrillation (a type of irregular heartbeat). A large study of 2007 persons 60 years old and older followed up for 10 years revealed that those persons with low serum thyrotropin concentrations had three times the risk of developing atrial fibrillation as did persons with normal thyrotropin concentrations. Hyperthyroidism is known to be a risk factor for atrial fibrillation, but older persons with atrial fibrillation usually do not also have hyperthyroidism. Subclinical (too small to be detected easily) hyperthyroidism is known to occur in older persons, and it is marked by a low serum thyrotropin concentration in persons with otherwise normal serum thyroid hormone concentrations. Identifying risk factors for atrial fibrillation is important because it may lead to stroke and decreased heart output. Older persons with low serum thyrotropin concentrations should be monitored for signs of hyperthyroidism and atrial fibrillation. Such persons receiving thyroid hormone therapy should receive lower doses.

Correctly diagnosing subclinical hyperthyroidism may be important because of its relationship to atrial fibrillation. Subclinical (too small or early to be detected) hyperthyroidism is marked by low concentrations of the thyroid hormone thyrotropin in the blood. New tests to measure serum thyrotropin concentrations are making it possible to identify persons at risk for developing atrial fibrillation. Persons with low serum thyrotropin concentrations may not exhibit clinical signs of hyperthyroidism, but their risk for developing atrial fibrillation may be three times that of persons with normal serum thyrotropin values. Carefully following such patients may be a better management strategy than intervening with antithyroid therapy.

Polybrominated diphenyl ether (PBDE) flame retardants have been added to a wide variety of U.S. consumer goods including automobiles, airplanes, electronics, home furnishings, and furniture. Although two forms of PBDEs [...]

Human exposure to polybrominated diphenylether (PBDE) flame retardants has increased significantly over the last three decades. Animal and human studies suggest that PBDEs may disrupt thyroid function; although thyroid hormone [...]

Environmental exposure of infants to perchlorate, thiocyanate, and nitrate might interfere with thyroid function. U.S. women with higher background perchlorate exposure have higher thyroid-stimulating hormone (TSH) levels and lower thyroxine [...]

A Harvard Medical School study found that abnormal thyrotropin levels in women are associated with the development of Alzheimer's disease. Researchers estimated the risk of developing dementia based on baseline [...]