Flavonoids, Thyroid Iodide Uptake and Thyroid Cancer—A Review

PubMed Central

Gonçalves, Carlos F. L.; de Freitas, Mariana L.; Ferreira, Andrea C. F.

2017-01-01

Thyroid cancer is the most common malignant tumor of the endocrine system and the incidence has been increasing in recent years. In a great part of the differentiated carcinomas, thyrocytes are capable of uptaking iodide. In these cases, the main therapeutic approach includes thyroidectomy followed by ablative therapy with radioiodine. However, in part of the patients, the capacity to concentrate iodide is lost due to down-regulation of the sodium-iodide symporter (NIS), the protein responsible for transporting iodide into the thyrocytes. Thus, therapy with radioiodide becomes ineffective, limiting therapeutic options and reducing the life expectancy of the patient. Excessive ingestion of some flavonoids has been associated with thyroid dysfunction and goiter. Nevertheless, studies have shown that some flavonoids can be beneficial for thyroid cancer, by reducing cell proliferation and increasing cell death, besides increasing NIS mRNA levels and iodide uptake. Recent data show that the flavonoids apingenin and rutin are capable of increasing NIS function and expression in vivo. Herein we review literature data regarding the effect of flavonoids on thyroid cancer, besides the effect of these compounds on the expression and function of the sodium-iodide symporter. We will also discuss the possibility of using flavonoids as adjuvants for therapy of thyroid cancer. PMID:28604619

12-month efficacy of a single radiofrequency ablation on autonomously functioning thyroid nodules.

PubMed

Bernardi, Stella; Stacul, Fulvio; Michelli, Andrea; Giudici, Fabiola; Zuolo, Giulia; de Manzini, Nicolò; Dobrinja, Chiara; Zanconati, Fabrizio; Fabris, Bruno

2017-09-01

Radiofrequency ablation has been advocated as an alternative to radioiodine and/or surgery for the treatment of autonomously functioning benign thyroid nodules. However, only a few studies have measured radiofrequency ablation efficacy on autonomously functioning benign thyroid nodules. The aim of this work was to evaluate the 12-month efficacy of a single session of radiofrequency ablation (performed with the moving shot technique) on solitary autonomously functioning benign thyroid nodules. Thirty patients with a single, benign autonomously functioning benign thyroid nodules, who were either unwilling or ineligible to undergo surgery and radioiodine, were treated with radiofrequency ablation between April 2012 and May 2015. All the patients underwent a single radiofrequency ablation, performed with the 18-gauge needle and the moving shot technique. Clinical, laboratory, and ultrasound evaluations were scheduled at baseline, and after 1, 3, 6, and 12 months from the procedure. A single radiofrequency ablation reduced thyroid nodule volume by 51, 63, 69, and 75 % after 1, 3, 6, and 12 months, respectively. This was associated with a significant improvement of local cervical discomfort and cosmetic score. As for thyroid function, 33 % of the patients went into remission after 3 months, 43 % after 6 months, and 50 % after 12 months from the procedure. This study demonstrates that a single radiofrequency ablation allowed us to withdraw anti-thyroid medication in 50 % of the patients, who remained euthyroid afterwards. This study shows that a single radiofrequency ablation was effective in 50 % of patients with autonomously functioning benign thyroid nodules. Patients responded gradually to the treatment. It is possible that longer follow-up studies might show greater response rates.

Tissue-engineered thyroid cell sheet rescued hypothyroidism in rat models after receiving total thyroidectomy comparing with nontransplantation models.

PubMed

Arauchi, Ayumi; Shimizu, Tatsuya; Yamato, Masayuki; Obara, Takao; Okano, Teruo

2009-12-01

For hormonal deficiency caused by endocrine organ diseases, continuous oral hormone administration is indispensable to supplement the shortage of hormones. In this study, as a more effective therapy, we have tried to reconstruct the three-dimensional thyroid tissue by the cell sheet technology, a novel tissue engineering approach. The cell suspension obtained from rat thyroid gland was cultured on temperature-responsive culture dishes, from which confluent cells detach as a cell sheet simply by reducing temperature without any enzymatic treatment. The 8-week-old Lewis rats were exposed to total thyroidectomy as hypothyroidism models and received thyroid cell sheet transplantation 1 week after total thyroidectomy. Serum levels of free triiodothyronine (fT(3)) and free thyroxine (fT(4)) significantly decreased 1 week after total thyroidectomy. On the other hand, transplantation of the thyroid cell sheets was able to restore the thyroid function 1 week after the cell sheet transplantation, and improvement was maintained for 4 weeks. Moreover, morphological analyses showed typical thyroid follicle organization, and anti-thyroid-transcription-factor-1 antibody staining demonstrated the presence of follicle epithelial cells. The presence of functional microvessels was also detected within the engineered thyroid tissues. In conclusion, our results indicate that thyroid cell sheets transplanted in a model of total thyroidectomy can reorganize histologically to resemble a typical thyroid gland and restore thyroid function in vivo. In this study, we are the first to confirm that engineered thyroid tissue can repair hypothyroidism models in rats and, therefore, cell sheet transplantation of endocrine organs may be suitable for the therapy of hormonal deficiency.

Effectiveness and Mechanism of Preoperative Lugol Solution for Reducing Thyroid Blood Flow in Patients with Euthyroid Graves' Disease.

PubMed

Huang, Shih-Ming; Liao, Wei-Ting; Lin, Chiou-Feng; Sun, H Sunny; Chow, Nan-Haw

2016-03-01

To reduce intraoperative and postoperative complications, using Lugol solution to preoperatively prepare patients with Graves' disease has (1) rapidly reduced the severity of thyrotoxicosis and (2) reduced the vascularity of the thyroid gland. The vascularity reduction normally accompanies reducing the severity of thyrotoxicosis. However, the effects and mechanism of Lugol solution for reducing blood flow have not been well investigated in the patients with euthyroid (normally functioning thyroid) Graves' disease. Twenty-five patients with euthyroid Graves' disease being preoperatively treated with Lugol solution for 10 days were measured, at baseline and on the operative day, for (1) superior thyroid artery blood flow; (2) systemic angiogenic factor (VEGF); and (3) systemic inflammatory factor [interleukin (IL)-16]. All three parameters were significantly (p < 0.0001) lower after 10 days of Lugol solution treatment. The average reductions were blood flow: 60% (0.294 vs. 0.117 L/min), serum VEGF: 55% (169.8 vs. 76.7 pg/mL), and serum IL-16: 50% (427.2 vs. 214.2; pg/mL). Lugol solution significantly reduced thyroid arterial blood flow, VEGF, and IL-16, even in patients with euthyroid Graves' disease. We recommend routine preoperative Lugol solution treatment for all patients with Graves' disease.

Differential expression of connexin 43 in human autoimmune thyroid disease.

PubMed

Jiang, Xiao-Yan; Feng, Xiao-Hong; Li, Guo-Yan; Zhao, Qian; Yin, Hui-Qing

2010-05-01

Gap junctions provide a pathway for cell-to-cell communication. Reduced thyroid epithelial cell-cell communication has been reported in some animal models of autoimmune thyroid disease. In order to assess whether this change was similar to human autoimmune thyroid disease, we identified some connexin proteins and their corresponding mRNA in human thyroid gland. The aim of our study was to explore the expression of connexin 43 (Cx43) in the thyroid gland from normal and diseased human thyroid tissue by immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR). The expression levels of Cx43 in Grave's disease were significantly increased in comparison with those of normal thyroid tissue. There was a significant decrease in expression of Cx43 in Hashimoto's thyroiditis, compared with normal thyroid tissue. These data indicate that changes of Cx43 expression in human autoimmune thyroid disease were associated with variations in thyroid function and hormone secretion. 2009 Elsevier GmbH. All rights reserved.

Withdrawal From Chronic Nicotine Reduces Thyroid Hormone Levels and Levothyroxine Treatment Ameliorates Nicotine Withdrawal-Induced Deficits in Hippocampus-Dependent Learning in C57BL/6J Mice

PubMed Central

Leach, Prescott T.; Holliday, Erica; Kutlu, Munir G.

2015-01-01

Introduction: Cigarette smoking alters a variety of endocrine systems including thyroid hormones. Altered thyroid hormone signaling may lead to a subclinical or overt hypothyroid condition that could contribute to nicotine withdrawal-related symptoms, such as cognitive deficits. Thus, normalizing thyroid hormone levels may represent a novel therapeutic target for ameliorating nicotine withdrawal-associated cognitive deficits. Methods: The current studies conducted an analysis of serum thyroid hormone levels after chronic and withdrawal from chronic nicotine treatment in C57BL/6J mice using an enzyme-linked immunosorbent assay. The present studies also evaluated the effect of synthetic thyroid hormone (levothyroxine) on contextual and cued memory. Results: The current studies found that nicotine withdrawal reduces secreted thyroid hormone levels by 9% in C57BL/6J mice. Further, supplemental thyroid hormone not only enhanced memory in naïve animals, but also ameliorated deficits in hippocampus-dependent learning associated with nicotine withdrawal. Conclusions: These results suggest that smokers attempting to quit should be monitored closely for changes in thyroid function. If successfully treated, normalization of thyroid hormone levels may ameliorate some deficits associated with nicotine withdrawal and this may lead to higher rates of successful abstinence. PMID:25358661

A tiered approach to evaluate an iodine recycling inhibition adverse outcome pathway (AOP) in amphibians

EPA Science Inventory

The enzyme iodotyrosine deiodinase (dehalogenase, IYD) catalyzes iodide recycling and promotes iodide retention in thyroid follicular cells. Loss of function or chemical inhibition of IYD reduces thyroid hormone synthesis, which leads to insufficiency in tissues and subsequent ne...

Thyroid storm masked by hemodialysis and glucocorticoid therapy in a patient with rheumatoid arthritis.

PubMed

Sasaki, Yohei; Shimizu, Yoshio; Nakata, Junichiro; Kameda, Toshiaki; Muto, Masahiro; Ohsawa, Isao; Io, Hiroaki; Hamada, Chieko; Horikoshi, Satoshi; Tomino, Yasuhiko

2012-01-01

Thyroid function test values are generally at low levels in patients with end-stage kidney disease. Life-threatening thyrotoxicosis or thyroid storm is rare, especially in hemodialysis (HD) patients, and is characterized by multisystem involvement and a high mortality rate if not immediately recognized and treated. Here, we report a female patient with severe symptomatic thyroid storm, receiving long-term HD and glucocorticoid therapy. Methimazole at a dose of 15 mg per day, β-adrenergic blockade and HD succeeded in controlling the patient's condition by gradually adjusting the target dry weight for hyperthyroidism-induced weight loss. When she was discharged from the hospital, her dry weight was reduced from 47.2 to 39.2 kg. The management of patients with severe symptomatic thyroid storm on HD represents a rare scenario. It is essential to initiate the available treatments as early as possible to reduce its mortality.

THYROID HORMONE INSUFFICIENCY DURING BRAIN DEVELOPMENT REDUCES PARVALBUMIN IMMUNOREACTIVITY AND INHIBITORY FUNCTION IN THE HIPPOCAMPUS.

EPA Science Inventory

The EPA must evaluate the risk of exposure of the developing brain to chemicals with the potential to disrupt thyroid hormone homeostasis. The existing literature identifies morphological and neurochemical indices of severe neonatal hypothyroidism in the early postnatal period i...

In vitro chemical screening assays to identify thyroid hormone disruptors.

EPA Science Inventory

Identification of chemicals with potential to impact thyroid hormone function is a priority of the US EPA’s Endocrine Disruptor Screening Program (EDSP). In vitro screening assays can be used to significantly reduce the number of chemicals that need to be considered for tes...

Developmental exposure to perchlorate alters synaptic transmission in hippocampus of the adult rat: in vivo studies.

EPA Science Inventory

Perchlorate, a contaminant found in food and water supplies throughout the USA, blocks iodine uptake into the thyroid gland to reduce circulating levels of thyroid hormone. Neurological function accompanying developmental exposure to perchlorate was evaluated in the present study...

Thyrotropin-Blocking Autoantibodies and Thyroid-Stimulating Autoantibodies: Potential Mechanisms Involved in the Pendulum Swinging from Hypothyroidism to Hyperthyroidism or Vice Versa

PubMed Central

Rapoport, Basil

2013-01-01

Background Thyrotropin receptor (TSHR) antibodies that stimulate the thyroid (TSAb) cause Graves' hyperthyroidism and TSHR antibodies which block thyrotropin action (TBAb) are occasionally responsible for hypothyroidism. Unusual patients switch from TSAb to TBAb (or vice versa) with concomitant thyroid function changes. We have examined case reports to obtain insight into the basis for “switching.” Summary TBAb to TSAb switching occurs in patients treated with levothyroxine (LT4); the reverse switch (TBAb to TSAb) occurs after anti-thyroid drug therapy; TSAb/TBAb alterations may occur during pregnancy and are well recognized in transient neonatal thyroid dysfunction. Factors that may impact the shift include: (i) LT4 treatment, usually associated with decreased thyroid autoantibodies, in unusual patients induces or enhances thyroid autoantibody levels; (ii) antithyroid drug treatment decreases thyroid autoantibody levels; (iii) hyperthyroidism can polarize antigen-presenting cells, leading to impaired development of regulatory T cells, thereby compromising control of autoimmunity; (iv) immune-suppression/hemodilution reduces thyroid autoantibodies during pregnancy and rebounds postpartum; (v) maternally transferred IgG transiently impacts thyroid function in neonates until metabolized; (vi) a Graves' disease model involving immunizing TSHR-knockout mice with mouse TSHR-adenovirus and transfer of TSHR antibody-secreting splenocytes to athymic mice demonstrates the TSAb to TBAb shift, paralleling the outcome of maternally transferred “term limited” TSHR antibodies in neonates. Finally, perhaps most important, as illustrated by dilution analyses of patients' sera in vitro, TSHR antibody concentrations and affinities play a critical role in switching TSAb and TBAb functional activities in vivo. Conclusions Switching between TBAb and TSAb (or vice versa) occurs in unusual patients after LT4 therapy for hypothyroidism or anti-thyroid drug treatment for Graves' disease. These changes involve differences in TSAb versus TBAb concentrations, affinities and/or potencies in individual patients. Thus, anti-thyroid drugs or suppression/hemodilution in pregnancy reduce initially low TSAb levels even further, leading to TBAb dominance. In contrast, TSAb emergence after LT4 administration may be sufficient to counteract TBAb inhibition. The occurrence of “switching” emphasizes the need for careful patient monitoring and management. Finally, whole genome screening of relatively rare “switch” patients and appropriate Graves' and Hashimoto's controls could provide unexpected and valuable information regarding the basis for thyroid autoimmunity. PMID:23025526

[Poorly differentiated thyroid carcinomas: new therapeutic considerations].

PubMed

Graf, Hans

2005-10-01

For most differentiated thyroid carcinomas, as papillary and follicular carcinomas, following total thyroidectomy and 131I therapy for thyroid remnant ablation, treatment with thyroid hormones to suppress TSH levels will reduce the growth of any remaining thyroid cancer cells, and thyroid cell-specific radiation therapy will either cure or control the disease. Thyroid carcinomas are considered poorly differentiated when they start to lose such functions as iodine uptake and thyrotropin-dependence for growth and production of thyroid proteins like NIS, thyroglobulin and desiodases. One of the greatest challenges in the management of patients with follicular cell-derived thyroid cancer is the treatment of tumors that progressed despite surgery, (131)I and T4 suppression of TSH. With the better knowledge of the abnormal molecular signaling in thyroid cancer cells, actually known targeted cancer therapies, directed against molecules involved in neoplastic transformation, are being used. As the critical molecular requirements for tumor initiation, maintenance and progression are identified, combination therapies with targeted agents acting on each of them will improve the treatment of poorly differentiated thyroid carcinoma.

Maternal urinary bisphenol a during pregnancy and maternal and neonatal thyroid function in the CHAMACOS study.

PubMed

Chevrier, Jonathan; Gunier, Robert B; Bradman, Asa; Holland, Nina T; Calafat, Antonia M; Eskenazi, Brenda; Harley, Kim G

2013-01-01

Bisphenol A (BPA) is widely used in the manufacture of polycarbonate plastic bottles, food and beverage can linings, thermal receipts, and dental sealants. Animal and human studies suggest that BPA may disrupt thyroid function. Although thyroid hormones play a determinant role in human growth and brain development, no studies have investigated relations between BPA exposure and thyroid function in pregnant women or neonates. Our goal was to evaluate whether exposure to BPA during pregnancy is related to thyroid hormone levels in pregnant women and neonates. We measured BPA concentration in urine samples collected during the first and second half of pregnancy in 476 women participating in the CHAMACOS (Center for the Health Assessment of Mothers and Children of Salinas) study. We also measured free thyroxine (T4), total T4, and thyroid-stimulating hormone (TSH) in women during pregnancy, and TSH in neonates. Associations between the average of the two BPA measurements and maternal thyroid hormone levels were not statistically significant. Of the two BPA measurements, only the one taken closest in time to the TH measurement was significantly associated with a reduction in total T4 (β = -0.13 µg/dL per log2 unit; 95% CI: -0.25, 0.00). The average of the maternal BPA concentrations was associated with reduced TSH in boys (-9.9% per log2 unit; 95% CI: -15.9%, -3.5%) but not in girls. Among boys, the relation was stronger when BPA was measured in the third trimester of pregnancy and decreased with time between BPA and TH measurements. Results suggest that exposure to BPA during pregnancy is related to reduced total T4 in pregnant women and decreased TSH in male neonates. Findings may have implications for fetal and neonatal development.

Notch3 expression correlates with thyroid cancer differentiation, induces apoptosis, and predicts disease prognosis.

PubMed

Somnay, Yash R; Yu, Xiao-Min; Lloyd, Ricardo V; Leverson, Glen; Aburjania, Zviadi; Jang, Samuel; Jaskula-Sztul, Renata; Chen, Herbert

2017-03-01

Thyroid tumorigenesis is characterized by a progressive loss of differentiation exhibited by a range of disease variants. The Notch receptor family (1-4) regulates developmental progression in both normal and cancerous tissues. This study sought to characterize the third Notch isoform (Notch3) across the various differentiated states of thyroid cancer, and determine its clinical impact. Notch3 expression was analyzed in a tissue microarray of normal and pathologic thyroid biopsies from 155 patients. The functional role of Notch3 was then investigated by upregulating its expression in a follicular thyroid cancer (FTC) cell line. Notch3 expression regressed across decreasingly differentiated, increasingly malignant thyroid specimens, correlated with clinicopathological attributes reflecting poor prognosis, and independently predicted survival following univariate and multivariate analyses. Overexpression of the active Notch3 intracellular domain (NICD3) in a gain-of-function FTC line led to functional activation of centromere-binding protein 1, while increasing thyroid-specific gene transcription. NICD3 induction also reduced tumor burden in vivo and initiated the intrinsic apoptotic cascade, alongside suppressing cyclin and B-cell lymphoma 2 family expression. Loss of Notch3 expression may be fundamental to the process of dedifferentiation that accompanies thyroid oncogenesis. Conversely, activation of Notch3 in thyroid cancer exerts an antiproliferative effect and restores elements of a differentiated phenotype. These findings provide preclinical rationale for evaluating Notch3 as a disease prognosticator and therapeutic target in advanced thyroid cancer. Cancer 2017;123:769-82. © 2016 American Cancer Society. © 2016 American Cancer Society.

Thyroid function in lung cancer

PubMed Central

Ratcliffe, J G; Stack, B H R; Burt, R W; Ratcliffe, W A; Spilg, W G S; Cuthbert, J; Kennedy, R S

1978-01-01

Thyroid function was assessed at the time of initial diagnosis in 204 patients with lung cancer and compared with that of age and sex-matched patients with non-malignant lung disease. Abnormalities in thyroid function were found in 67 patients (33%). The most prevalent abnormality was a low T3 concentration; this was not associated with other clinical or biochemical evidence of hypothyroidism, but the short-term prognosis of these patients was worse than that of matched patients with lung cancer having normal T3 concentrations. Primary hypothyroidism occurred in three patients, low T4 concentrations and free thyroxine index (FTI) with normal thyrotrophin (TSH) concentrations in four patients, and moderately raised TSH with normal thyroid hormone concentrations in six patients; nine patients had a raised FTI with or without raised T4 concentration as the sole abnormality. Overall, the pattern of thyroid hormone metabolism in lung cancer was a tendency towards reduced T3 concentrations with significantly increased T4/T3 ratios and modestly increased 3,3′,5′-triiodothyronine (rT3) concentrations. The altered T4/T3 ratio was particularly noticeable in patients with anaplastic tumours of small (“oat cell”) and large cell types, but was not apparently related to detectable extrathoracic metastases. These data suggest that thyroid hormone metabolism is altered in patients with lung cancer by decreased 5′-monodeiodination of T4. The resulting low T3 concentrations and altered T4/T3 ratio may be partly responsible for the reduced ratio of androsterone to aetiocholanolone observed in lung cancer, which is known to be a poor prognostic sign. PMID:620266

The effects of Nigella sativa on thyroid function, serum Vascular Endothelial Growth Factor (VEGF) - 1, Nesfatin-1 and anthropometric features in patients with Hashimoto's thyroiditis: a randomized controlled trial.

PubMed

Farhangi, Mahdieh Abbasalizad; Dehghan, Parvin; Tajmiri, Siroos; Abbasi, Mehran Mesgari

2016-11-16

Hashimoto's thyroiditis is an autoimmune disorder and the most common cause of hypothyroidism. The use of Nigella sativa, a potent herbal medicine, continues to increase worldwide as an alternative treatment of several chronic diseases including hyperlipidemia, hypertension and type 2 diabetes mellitus (T2DM). The aim of the current study was to evaluate the effects of Nigella sativa on thyroid function, serum Vascular Endothelial Growth Factor (VEGF) - 1, Nesfatin-1 and anthropometric features in patients with Hashimoto's thyroiditis. Forty patients with Hashimoto's thyroiditis, aged between 22 and 50 years old, participated in the trial and were randomly allocated into two groups of intervention and control receiving powdered Nigella sativa or placebo daily for 8 weeks. Changes in anthropometric variables, dietary intakes, thyroid status, serum VEGF and Nesfatin-1 concentrations after 8 weeks were measured. Treatment with Nigella sativa significantly reduced body weight and body mass index (BMI). Serum concentrations of thyroid stimulating hormone (TSH) and anti-thyroid peroxidase (anti-TPO) antibodies decreased while serum T3 concentrations increased in Nigella sativa-treated group after 8 weeks. There was a significant reduction in serum VEGF concentrations in intervention group. None of these changes had been observed in placebo treated group. In stepwise multiple regression model, changes in waist to hip ratio (WHR) and thyroid hormones were significant predictors of changes in serum VEGF and Nesgfatin-1 values in Nigella sativa treated group (P < 0.05). Our data showed a potent beneficial effect of powdered Nigella sativa in improving thyroid status and anthropometric variables in patients with Hashimoto's thyroiditis. Moreover, Nigella sativa significantly reduced serum VEGF concentrations in these patients. Considering observed health- promoting effect of this medicinal plant in ameliorating the disease severity, it can be regarded as a useful therapeutic approach in management of Hashimoto's thyroiditis. Iranian registry of clinical trials (registration number IRCT2015021719082N4 - Registered March-15-2015).

Comparative effects of in ovo exposure to sodium perchlorate on development, growth, metabolism, and thyroid function in the common snapping turtle (Chelydra serpentina) and red-eared slider (Trachemys scripta elegans).

PubMed

Eisenreich, Karen M; Dean, Karen M; Ottinger, Mary Ann; Rowe, Christopher L

2012-11-01

Perchlorate is a surface and groundwater contaminant found in areas associated with munitions and rocket manufacturing and use. It is a thyroid-inhibiting compound, preventing uptake of iodide by the thyroid gland, ultimately reducing thyroid hormone production. As thyroid hormones influence metabolism, growth, and development, perchlorate exposure during the embryonic period may impact embryonic traits that ultimately influence hatchling performance. We topically exposed eggs of red-eared sliders (Trachemys scripta) and snapping turtles (Chelydra serpentina) to 200 and 177 μg/g of perchlorate (as NaClO(4)), respectively, to determine impacts on glandular thyroxine concentrations, embryonic growth and development, and metabolic rates of hatchlings for a period of 2 months post-hatching. In red-eared sliders, in ovo perchlorate exposure delayed hatching, increased external yolk size at hatching, increased hatchling mortality, and reduced total glandular thyroxine concentrations in hatchlings. In snapping turtles, hatching success and standard metabolic rates were reduced, liver and thyroid sizes were increased, and total glandular thyroxine concentrations in hatchlings were reduced after exposure to perchlorate. While both species were negatively affected by exposure, impacts on red-eared sliders were most severe, suggesting that the slider may be a more sensitive sentinel species for studying effects of perchlorate exposure to turtles. Copyright © 2012 Elsevier Inc. All rights reserved.

Flavonoid Rutin Increases Thyroid Iodide Uptake in Rats

PubMed Central

Lima Gonçalves, Carlos Frederico; de Souza dos Santos, Maria Carolina; Ginabreda, Maria Gloria; Soares Fortunato, Rodrigo; Pires de Carvalho, Denise; Freitas Ferreira, Andrea Claudia

2013-01-01

Thyroid iodide uptake through the sodium-iodide symporter (NIS) is not only an essential step for thyroid hormones biosynthesis, but also fundamental for the diagnosis and treatment of different thyroid diseases. However, part of patients with thyroid cancer is refractory to radioiodine therapy, due to reduced ability to uptake iodide, which greatly reduces the chances of survival. Therefore, compounds able to increase thyroid iodide uptake are of great interest. It has been shown that some flavonoids are able to increase iodide uptake and NIS expression in vitro, however, data in vivo are lacking. Flavonoids are polyhydroxyphenolic compounds, found in vegetables present in human diet, and have been shown not only to modulate NIS, but also thyroperoxidase (TPO), the key enzyme in thyroid hormones biosynthesis, besides having antiproliferative effect in thyroid cancer cell lines. Therefore, we aimed to evaluate the effect of some flavonoids on thyroid iodide uptake in Wistar rats in vivo. Among the flavonoids tested, rutin was the only one able to increase thyroid iodide uptake, so we decided to evaluate the effect of this flavonoid on some aspects of thyroid hormones synthesis and metabolism. Rutin led to a slight reduction of serum T4 and T3 without changes in serum thyrotropin (TSH), and significantly increased hypothalamic, pituitary and brown adipose tissue type 2 deiodinase and decreased liver type 1 deiodinase activities. Moreover, rutin treatment increased thyroid iodide uptake probably due to the increment of NIS expression, which might be secondary to increased response to TSH, since TSH receptor expression was increased. Thus, rutin might be useful as an adjuvant in radioiodine therapy, since this flavonoid increased thyroid iodide uptake without greatly affecting thyroid function. PMID:24023911

Overexpression of Interleukin-4 in the Thyroid of Transgenic Mice Upregulates the Expression of Duox1 and the Anion Transporter Pendrin

PubMed Central

Achouri, Younes; Hahn, Stephan; Many, Marie-Christine; Craps, Julie; Refetoff, Samuel; Liao, Xiao-Hui; Dumont, Jacques E.; Van Sande, Jacqueline; Corvilain, Bernard; Miot, Françoise; De Deken, Xavier

2016-01-01

Background: The dual oxidases (Duox) are involved in hydrogen peroxide generation, which is essential for thyroid hormone synthesis, and therefore they are markers of thyroid function. During inflammation, cytokines upregulate DUOX gene expression in the airway and the intestine, suggesting a role for these proteins in innate immunity. It was previously demonstrated that interleukin-4 (IL-4) upregulates DUOX gene expression in thyrocytes. Although the role of IL-4 in autoimmune thyroid diseases has been studied extensively, the effects of IL-4 on thyroid physiology remain largely unknown. Therefore, a new animal model was generated to study the impact of IL-4 on thyroid function. Methods: Transgenic (Thyr-IL-4) mice with thyroid-targeted expression of murine IL-4 were generated. Transgene expression was verified at the mRNA and protein level in thyroid tissues and primary cultures. The phenotype of the Thyr-IL-4 animals was characterized by measuring serum thyroxine (T4) and thyrotropin levels and performing thyroid morphometric analysis, immunohistochemistry, whole transcriptome sequencing, quantitative reverse transcription polymerase chain reaction, and ex vivo thyroid function assays. Results: Thyrocytes from two Thyr-IL-4 mouse lines (#30 and #52) expressed IL-4, which was secreted into the extracellular space. Although 10-month-old transgenic animals had T4 and thyrotropin serum levels in the normal range, they had altered thyroid follicular structure with enlarged follicles composed of elongated thyrocytes containing numerous endocytic vesicles. These follicles were positive for T4 staining the colloid, indicating their capacity to produce thyroid hormones. RNA profiling of Thyr-IL-4 thyroid samples revealed modulation of multiple genes involved in inflammation, while no major leukocyte infiltration could be detected. Upregulated expression of Duox1, Duoxa1, and the pendrin anion exchanger gene (Slc26a4) was detected. In contrast, the iodide symporter gene Slc5a5 was markedly downregulated resulting in impaired iodide uptake and reduced thyroid hormone levels in transgenic thyroid tissue. Hydrogen peroxide production was increased in Thyr-IL-4 thyroid tissue compared with wild-type animals, but no significant oxidative stress could be detected. Conclusions: This is the first study to show that ectopic expression of IL-4 in thyroid tissue upregulates Duox1/Duoxa1 and Slc26a4 expression in the thyroid. The present data demonstrate that IL-4 could affect thyroid morphology and function, mainly by downregulating Slc5a5 expression, while maintaining a normal euthyroid phenotype. PMID:27599561

The effect of thyroid hormone and a long-acting somatostatin analogue on TtT-97 murine thyrotropic tumors.

PubMed

Woodmansee, W W; Gordon, D F; Dowding, J M; Stolz, B; Lloyd, R V; James, R A; Wood, W M; Ridgway, E C

2000-07-01

Thyroid hormone inhibits thyrotropin (TSH) production and thyrotrope growth. Somatostatin has been implicated as a synergistic factor in the inhibition of thyrotrope function. We have previously shown that pharmacological doses of thyroid hormone (levothyroxine [LT4]) inhibit growth of murine TtT-97 thyrotropic tumors in association with upregulation of somatostatin receptor type 5 (sst5) mRNA and somatostatin receptor binding. In the current study, we examined the effect of physiological thyroid hormone replacement alone or in combination with the long-acting somatostatin analogue, Sandostatin LAR, on thyrotropic tumor growth, thyrotropin growth factor-beta (TSH-beta), and sst5 mRNA expression, as well as somatostatin receptor binding sites. Physiological LT4 replacement therapy resulted in tumor shrinkage in association with increased sst5 mRNA levels, reduced TSH-beta mRNA levels and enhanced somatostatin receptor binding. Sandostatin LAR alone had no effect on any parameter measured. However, Sandostatin LAR combined with LT4 synergistically inhibited TSH-beta mRNA production and reduced final tumor weights to a greater degree. In this paradigm, Sandostatin LAR required a euthyroid status to alter thyrotrope parameters. These data suggest an important interaction between the somatostatinergic system and thyroid hormone in the regulation of thyrotrope cell structure and function.

The effect of metformin on the hypothalamic-pituitary-thyroid axis in patients with type 2 diabetes and subclinical hyperthyroidism.

PubMed

Krysiak, R; Szkrobka, W; Okopien, B

2015-04-01

In hypothyroid patients, metformin was found to reduce serum levels of TSH. No previous study investigated metformin action on hypothalamic-pituitary-thyroid axis in patients with hyperthyroidism. The aim of our study was to assess the effect of metformin treatment on thyroid function tests in patients with untreated subclinical hyperthyroidism. We studied 15 patients with low but detectable TSH levels (0.1-0.4 mIU/L) (group 1), 12 patients with suppressed TSH levels (less than 0.1 mIU/L) (group 2) and 15 euthyroid patients with a history of hyperthyroidism, who because of coexisting 2 diabetes were treated with metformin (2.55-3 g daily). Glucose homeostasis markers, as well as serum levels of TSH and total and free thyroxine and triiodothyronine levels were assessed at baseline and after 3 and 6 months of therapy. As expected, metformin reduced plasma glucose, insulin resistance and glycated hemoglobin. However, with the exception of an insignificant decrease in TSH levels after 3-month therapy in group 2, metformin therapy did not affect thyroid function tests. Our results indicate that metformin has a negligible effect on hypothalamic-pituitary-thyroid axis activity in type 2 diabetic patients with subclinical hyperthyroidism. © Georg Thieme Verlag KG Stuttgart · New York.

Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.

PubMed

Martinez, Bridget; Scheibner, Michael; Soñanez-Organis, José G; Jaques, John T; Crocker, Daniel E; Ortiz, Rudy M

2017-10-01

Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

Marked suppression of thyroid function in rats with gram-negative septicemia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kan, M.K.; Garcia, J.F.; McRae, J.

1976-02-01

Gram-negative septicemia was induced in rats by two daily injections of fecal mixture into the thigh, after which the thyroid function was markedly suppressed for 2 days. Iodine metabolism was studied by organ radioassay and by imaging with a multiwire proportional chamber (MWPC) at various time intervals after intravenous injection of $sup 125$I. Plasma T$sub 3$, T$sub 4$, and TSH, measured by radioimmunoassays, were suppressed, as were the T$sub 3$-resin uptakes. Fractional blood supply to the thyroid glands of the infected rats, studied by the $sup 81$Rb uptake method, was also found to be markedly reduced. Sections of the thyroidmore » glands showed little structural change during the period of marked thyroid suppression. There was no biochemical evidence of renal failure in the septicemic rats. (auth)« less

Developmental Exposure to Perchlorate Alters Synaptic Transmission in Hippocampus of the Adult Rat

PubMed Central

Gilbert, Mary E.; Sui, Li

2008-01-01

Background Perchlorate is an environmental contaminant that blocks iodine uptake into the thyroid gland and reduces thyroid hormones. This action of perchlorate raises significant concern over its effects on brain development. Objectives The purpose of this study was to evaluate neurologic function in rats after developmental exposure to perchlorate. Methods Pregnant rats were exposed to 0, 30, 300, or 1,000 ppm perchlorate in drinking water from gestational day 6 until weaning. Adult male offspring were evaluated on a series of behavioral tasks and neurophysiologic measures of synaptic function in the hippocampus. Results At the highest perchlorate dose, triiodothyronine (T3) and thyroxine (T4) were reduced in pups on postnatal day 21. T4 in dams was reduced relative to controls by 16%, 28%, and 60% in the 30-, 300-, and 1,000-ppm dose groups, respectively. Reductions in T4 were associated with increases in thyroid-stimulating hormone in the high-dose group. No changes were seen in serum T3. Perchlorate did not impair motor activity, spatial learning, or fear conditioning. However, significant reductions in baseline synaptic transmission were observed in hippocampal field potentials at all dose levels. Reductions in inhibitory function were evident at 300 and 1,000 ppm, and augmentations in long-term potentiation were observed in the population spike measure at the highest dose. Conclusions Dose-dependent deficits in hippocampal synaptic function were detectable with relatively minor perturbations of the thyroid axis, indicative of an irreversible impairment in synaptic transmission in response to developmental exposure to perchlorate. PMID:18560531

[Apathetic hyperthyroidism with heart failure in an elderly patient with Plummer's disease].

PubMed

Narisawa, Manabu; Okada, Yosuke; Arao, Tadashi; Kuno, Fumi; Tanaka, Yoshiya

2014-12-01

We report a case of apathetic hyperthyroidism associated with unrecognized slowly growing functional thyroid adenoma (Plummer's disease), atrial fibrillation and heart failure. An 81-year-old woman with worsening thyroid dysfunction was admitted to our hospital for the treatment of heart failure. The patient had developed heart failure associated with chronic atrial fibrillation at 76 years of age, and one year later was found to have asymptomatic hyperthyroidism. Anti-thyroid autoantibodies were negative, but thyroid echography showed a 32-mm tumor devoid of internal blood flow in the left lower lobe. Free thyroxine 4 (FT4) decreased from 3.30 to 2.60 ng/dl without treatment. The patient was diagnosed with transient thyroiditis and was followed-up without treatment. However, a repeat thyroid echography showed growth of the tumor to 41 mm in 4 years. Thyroid scintigraphy showed uptake that matched the thyroid mass. Based on these findings, the established diagnosis was Plummer's disease complicated with heart failure. The patient was treated with anti-thyroid drugs, which resulted in improvement of FT4 and reduced the severity of heart failure. In this rare case of an elderly patient, Plummer's disease was associated with a slowly-growing functional thyroid adenoma, apathetic hyperthyroidism, repeated episodes of atrial fibrillation and heart failure. Since symptoms of thyrotoxicosis are likely to be missed in the elderly, it is necessary to include hyperthyroidism in the pathoetiology of heart failure and atrial fibrillation in this population.

Thyroiditis: an integrated approach.

PubMed

Sweeney, Lori B; Stewart, Christopher; Gaitonde, David Y

2014-09-15

Thyroiditis is a general term that encompasses several clinical disorders characterized by inflammation of the thyroid gland. The most common is Hashimoto thyroiditis; patients typically present with a nontender goiter, hypothyroidism, and an elevated thyroid peroxidase antibody level. Treatment with levothyroxine ameliorates the hypothyroidism and may reduce goiter size. Postpartum thyroiditis is transient or persistent thyroid dysfunction that occurs within one year of childbirth, miscarriage, or medical abortion. Release of preformed thyroid hormone into the bloodstream may result in hyperthyroidism. This may be followed by transient or permanent hypothyroidism as a result of depletion of thyroid hormone stores and destruction of thyroid hormone-producing cells. Patients should be monitored for changes in thyroid function. Beta blockers can treat symptoms in the initial hyperthyroid phase; in the subsequent hypothyroid phase, levothyroxine should be considered in women with a serum thyroid-stimulating hormone level greater than 10 mIU per L, or in women with a thyroid-stimulating hormone level of 4 to 10 mIU per L who are symptomatic or desire fertility. Subacute thyroiditis is a transient thyrotoxic state characterized by anterior neck pain, suppressed thyroid-stimulating hormone, and low radioactive iodine uptake on thyroid scanning. Many cases of subacute thyroiditis follow an upper respiratory viral illness, which is thought to trigger an inflammatory destruction of thyroid follicles. In most cases, the thyroid gland spontaneously resumes normal thyroid hormone production after several months. Treatment with high-dose acetylsalicylic acid or nonsteroidal anti-inflammatory drugs is directed toward relief of thyroid pain.

Pax8 modulates the expression of Wnt4 that is necessary for the maintenance of the epithelial phenotype of thyroid cells

PubMed Central

2014-01-01

Background The transcription factor Pax8 is expressed during thyroid development and is involved in the morphogenesis of the thyroid gland and maintenance of the differentiated phenotype. In particular, Pax8 has been shown to regulate genes that are considered markers of thyroid differentiation. Recently, the analysis of the gene expression profile of FRTL-5 differentiated thyroid cells after the silencing of Pax8 identified Wnt4 as a novel target. Like the other members of the Wnt family, Wnt4 has been implicated in several developmental processes including regulation of cell fate and patterning during embryogenesis. To date, the only evidence on Wnt4 in thyroid concerns its down-regulation necessary for the progression of thyroid epithelial tumors. Results Here we demonstrate that Pax8 is involved in the transcriptional modulation of Wnt4 gene expression directly binding to its 5’-flanking region, and that Wnt4 expression in FRTL-5 cells is TSH-dependent. Interestingly, we also show that in thyroid cells a reduced expression of Wnt4 correlates with the alteration of the epithelial phenotype and that the overexpression of Wnt4 in thyroid cancer cells is able to inhibit cellular migration. Conclusions We have identified and characterized a functional Pax8 binding site in the 5’-flanking region of the Wnt4 gene and we show that Pax8 modulates the expression of Wnt4 in thyroid cells. Taken together, our results suggest that in thyroid cells Wnt4 expression correlates with the integrity of the epithelial phenotype and is reduced when this integrity is perturbed. In the end, we would like to suggest that the overexpression of Wnt4 in thyroid cancer cells is able to revert the mesenchymal phenotype. PMID:25270402

Exogenous T3 toxicosis following consumption of a contaminated weight loss supplement.

PubMed

D'Arcy, R; McDonnell, M; Spence, K; Courtney, C H

2017-01-01

A 42-year-old male presented with a one-week history of palpitations and sweating episodes. The only significant history was of longstanding idiopathic dilated cardiomyopathy. Initial ECG demonstrated a sinus tachycardia. Thyroid function testing, undertaken as part of the diagnostic workup, revealed an un-measureable thyroid-stimulating hormone (TSH) and free thyroxine (T 4 ). Upon questioning the patient reported classical thyrotoxic symptoms over the preceding weeks. Given the persistence of symptoms free tri-iodothyronine (T 3 ) was measured and found to be markedly elevated at 48.9 pmol/L (normal range: 3.1-6.8 pmol/L). No goitre or nodular disease was palpable in the neck. Historically there had never been any amiodarone usage. Radionucleotide thyroid uptake imaging ( 123 I) demonstrated significantly reduced tracer uptake in the thyroid. Upon further questioning the patient reported purchasing a weight loss product online from India which supposedly contained sibutramine. He provided one of the tablets and laboratory analysis confirmed the presence of T 3 in the tablet. Full symptomatic resolution and normalised thyroid function ensued upon discontinuation of the supplement. Free tri-iodothyronine (T 3 ) measurement may be useful in the presence of symptoms suggestive of thyrotoxicosis with discordant thyroid function tests.Thyroid uptake scanning can be a useful aid to differentiating exogenous hormone exposure from endogenous hyperthyroidism.Ingestion of thyroid hormone may be inadvertent in cases of exogenous thyrotoxicosis.Medicines and supplements sourced online for weight loss may contain thyroxine (T 4 ) or T 3 and should be considered as a cause of unexplained exogenous hyperthyroidism.

The spectrum of thyroid disease and risk of new onset atrial fibrillation: a large population cohort study.

PubMed

Selmer, Christian; Olesen, Jonas Bjerring; Hansen, Morten Lock; Lindhardsen, Jesper; Olsen, Anne-Marie Schjerning; Madsen, Jesper Clausager; Faber, Jens; Hansen, Peter Riis; Pedersen, Ole Dyg; Torp-Pedersen, Christian; Gislason, Gunnar Hilmar

2012-11-27

To examine the risk of atrial fibrillation in relation to the whole spectrum of thyroid function in a large cohort of patients. Population based cohort study of general practice patients identified by linkage of nationwide registries at the individual level. Primary care patients in the city of Copenhagen. Registry data for 586,460 adults who had their thyroid function evaluated for the first time by their general practitioner during 2000-10 and who were without previously recorded thyroid disease or atrial fibrillation. Poisson regression models used to estimate risk of atrial fibrillation by thyroid function. Of the 586,460 individuals in the study population (mean (SD) age 50.2 (16.9) years, 39% men), 562,461 (96.0%) were euthyroid, 1670 (0.3%) had overt hypothyroidism, 12,087 (2.0%) had subclinical hypothyroidism, 3966 (0.7%) had overt hyperthyroidism, and 6276 (1.0%) had subclinical hyperthyroidism. Compared with the euthyroid individuals, the risk of atrial fibrillation increased with decreasing levels of thyroid stimulating hormone (TSH) from high normal euthyroidism (incidence rate ratio 1.12 (95% CI 1.03 to 1.21)) to subclinical hyperthyroidism with reduced TSH (1.16 (0.99 to 1.36)) and subclinical hyperthyroidism with supressed TSH (1.41 (1.25 to 1.59)). Both overt and subclinical hypothyroidism were associated with a lower risk of atrial fibrillation. The risk of atrial fibrillation was closely associated with thyroid activity, with a low risk in overt hypothyroidism, high risk in hyperthyroidism, and a TSH level dependent association with risk of atrial fibrillation across the spectrum of subclinical thyroid disease.

Dual ectopic thyroid associated with thyroid hemiagenesis.

PubMed

Nakamura, Shigenori; Masuda, Teruyuki; Ishimori, Masatoshi

2018-01-01

We report a case of a 15-year-old girl with a midline neck mass that was first noted 2 or 3 years previously. She had been treated with levothyroxine (L-T4) for congenital hypothyroidism until 11 years of age. Ultrasonography revealed an atrophic right thyroid (1.0 × 1.6 × 2.6 cm in size) and a mass (2.3 × 1.0 × 3.5 cm in size) in the upper part of the neck. No left lobe of the thyroid was detected. On further evaluation, Tc-99m pertechnetate thyroid scintigraphy and CT showed ectopic thyroid tissue in the lingual region and infrahyoid region. Thus, she was diagnosed as having dual ectopic thyroid and thyroid hemiagenesis. The atrophic right thyroid was thought be non-functional. Treatment with L-T4 was started to reduce the size of the dual ectopic thyroid tissue. This may be the first reported case of dual ectopic thyroid associated with hemiagenesis detected only by ultrasonography. Ultrasonography can confirm the presence or absence of orthotopic thyroid tissue in patients with ectopic thyroid.The cause of congenital hypothyroidism should be examined.Clinical manifestation of ectopic thyroid may appear when the treatment with L-T4 is discontinued.Annual follow-up is needed in all children when their thyroid hormone replacement is stopped.

Efficacy of a Home-Based Exercise Program After Thyroidectomy for Thyroid Cancer Patients.

PubMed

Kim, Kyunghee; Gu, Mee Ock; Jung, Jung Hwa; Hahm, Jong Ryeal; Kim, Soo Kyoung; Kim, Jin Hyun; Woo, Seung Hoon

2018-02-01

The objective of this study was to determine the effect of a home-based exercise program on fatigue, anxiety, quality of life (QoL), and immune function of thyroid cancer patients taking thyroid hormone replacement after thyroidectomy. This quasi-experimental study with a non-equivalent control group included 43 outpatients taking thyroid hormone replacement after thyroidectomy (22 in the experimental group and 21 in the control group). After education about the home-based exercise program, subjects in the experimental group underwent 12 weeks of aerobic, resistance, and flexibility exercise. A comparative analysis was conducted between the two groups. Patients in the experimental group were significantly less fatigued or anxious (p < 0.01). They reported significantly improved QoL (p < 0.05) compared to those in the control group. Natural killer cell activity was significantly higher in the exercise group compared to that in the control group (p < 0.05). A home-based exercise program is effective in reducing fatigue and anxiety, improving QoL, and increasing immune function in patients taking thyroid hormone replacement after thyroidectomy. Therefore, such a home-based exercise program can be used as an intervention for patients who are taking thyroid hormone replacement after thyroidectomy.

Reversal deterioration of renal function accompanied with primary hypothyrodism.

PubMed

Dragović, Tamara

2012-02-01

Hypothyroidism is often accompanied with decline of kidney function, or inability to maintain electrolyte balance. These changes are usually overlooked in everyday practice. Early recognition of this association eliminates unnecessary diagnostic procedures that postpone the adequate treatment. Two patients with elevated serum creatinine levels due to primary autoimmune hypothyroidism, with complete recovery of creatinine clearance after thyroid hormone substitution therapy are presented. The first patient was a young male whose laboratory tests suggested acute renal failure, and the delicate clinical presentation of reduced thyroid function. The second patient was an elderly woman with a history of a long-term signs and symptoms attributed to ageing, including the deterioration of renal function, with consequently delayed diagnosis of hypothyroidism. Serum thyrotropin and thyroxin levels measurement should be done in all cases of renal failure with undefined renal desease, even if the typical clinical presentation of hypothyroidism is absent. Thyroid hormone assays sholud also be performed in all patients with chronic kidney disease whose kidney function is rapidly worsening.

Is visual assessment of thyroid attenuation on unenhanced CT of the chest useful for detecting hypothyroidism?

PubMed

Maldjian, P D; Chen, T

2016-11-01

To determine if visual assessment of the attenuation of morphologically normal appearing thyroid glands on unenhanced computed tomography (CT) of the chest is useful for identifying patients with decreased thyroid function. This was a retrospective study of 765 patients who underwent both unenhanced CT of the chest and thyroid function tests performed within 1 year of the CT examination. Attenuation of the thyroid gland was visually assessed in each patient relative to the attenuation of the surrounding muscles to categorise the gland as "low attenuation" (attenuation similar to surrounding muscles) or "high attenuation" (attenuation greater than surrounding muscles). Thyroid attenuation was quantitatively measured in each case to determine the validity of the visual assessment. Results of thyroid function tests were used to classify thyroid function as hypothyroid, euthyroid, or hyperthyroid. Data were analysed to determine the relationship between visual assessment of thyroid attenuation and status of thyroid function. Thyroid glands of low attenuation were present in 4.2% (32/765) of the patients. Nearly half (47%) of the patients with low-attenuation thyroids had hypofunctioning thyroid glands. Compared to patients with high-attenuation thyroids, patients with low-attenuation thyroids were significantly more likely to have decreased thyroid function (clinical and subclinical hypothyroidism) and significantly less likely to be euthyroid (p<0.0001). Quantitative measurement of thyroid attenuation confirmed the validity of the visual assessment. Low attenuation of an otherwise normal-appearing thyroid gland on unenhanced CT of the chest is strongly associated with decreased thyroid function. Copyright © 2016 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

Asymptomatic hyperthyroidism in older adults: is it a distinct clinical and laboratory entity?

PubMed

Mooradian, Arshag D

2008-01-01

Hyperthyroidism is the result of increased serum free thyroid hormone levels and is associated with a well recognized set of clinical signs and symptoms. However, older patients who develop hyperthyroidism tend to have fewer hyperadrenergic signs and an increased incidence of weight loss, cardiac arrhythmias and, occasionally, apathetic mood. This article highlights the paucity of clinical signs and symptoms of hyperthyroidism in older people and reviews the potential biochemical changes in thyroid hormone physiology that may account for an altered clinical presentation in older people with hyperthyroidism. First, a brief vignette from our own clinical practice is described to highlight an unusual presentation of hyperthyroidism in an older woman. The subject is then reviewed on the basis of relevant articles identified through a MEDLINE search of the English literature, using the key words 'hyperthyroidism' and 'aging'. The available evidence indicates that the clinical syndrome of asymptomatic hyperthyroidism in older adults appears to be distinct from the more widely recognized syndromes of apathetic hyperthyroidism or thyroid hormone resistance. Age-related changes in thyroid hormone economy and reduced cellular uptake of thyroid hormone as well as changes in thyroid hormone regulation of gene expression may account for reduced manifestations of hyperthyroidism in older adults. Thus, in addition to the well known changes in thyroid gland anatomy and function with aging, there may be an age-related resistance to thyroid hormone action. Asymptomatic hyperthyroidism may well be a syndrome that is currently under-diagnosed.

Targeting glutaminase-mediated glutamine dependence in papillary thyroid cancer.

PubMed

Yu, Yang; Yu, Xiaohui; Fan, Chenling; Wang, Hong; Wang, Renee; Feng, Chen; Guan, Haixia

2018-06-25

Papillary thyroid cancer is a prevalent endocrine malignancy. Although alterations in glutamine metabolism have been reported in several types of hematological and solid tumors, little is known about the functions of glutamine and glutaminolysis-associated proteins in papillary thyroid cancer. Here, we demonstrated the glutamine dependence of papillary thyroid cancer cells, and with the use of RT 2 -PCR arrays, we screened for the aberrant overexpression of glutaminase in human papillary thyroid cancer tissues and cells. These results were later confirmed via real-time PCR, Western blots, and immunohistochemical staining. We found that the levels of glutaminase were significantly correlated with extrathyroidal extension. Inhibition of GLS suppressed glutaminolysis and reduced mitochondrial respiration. The proliferative, viable, migratory, and invasive abilities of papillary thyroid cancer cells were impaired by both the pharmacological inhibition and the genetic knockdown of glutaminase. Additionally, the inhibition of glutaminase deactivated the mechanistic target of the rapamycin complex 1 (mTORC1) signaling pathway, promoting autophagy and apoptosis. Collectively, these findings show that glutaminase-mediated glutamine dependence may be a potential therapeutic target for papillary thyroid cancer. PTC cells are glutamine-dependent, and GLS is aberrantly overexpressed in PTC. Inhibition of GLS suppressed glutaminolysis and reduced mitochondrial respiration. Inhibition of GLS impairs the viability of PTC cells. GLS blockade causes deactivation of mTORC1 and induction of autophagy and apoptosis. GLS may be a potential therapeutic target for PTC.

The spectrum of thyroid disease and risk of new onset atrial fibrillation: a large population cohort study

PubMed Central

Olesen, Jonas Bjerring; Hansen, Morten Lock; Lindhardsen, Jesper; Olsen, Anne-Marie Schjerning; Madsen, Jesper Clausager; Faber, Jens; Hansen, Peter Riis; Pedersen, Ole Dyg; Torp-Pedersen, Christian; Gislason, Gunnar Hilmar

2012-01-01

Objectives To examine the risk of atrial fibrillation in relation to the whole spectrum of thyroid function in a large cohort of patients. Design Population based cohort study of general practice patients identified by linkage of nationwide registries at the individual level. Setting Primary care patients in the city of Copenhagen. Subjects Registry data for 586 460 adults who had their thyroid function evaluated for the first time by their general practitioner during 2000-10 and who were without previously recorded thyroid disease or atrial fibrillation. Main outcome measure Poisson regression models used to estimate risk of atrial fibrillation by thyroid function. Results Of the 586 460 individuals in the study population (mean (SD) age 50.2 (16.9) years, 39% men), 562 461 (96.0%) were euthyroid, 1670 (0.3%) had overt hypothyroidism, 12 087 (2.0%) had subclinical hypothyroidism, 3966 (0.7%) had overt hyperthyroidism, and 6276 (1.0%) had subclinical hyperthyroidism. Compared with the euthyroid individuals, the risk of atrial fibrillation increased with decreasing levels of thyroid stimulating hormone (TSH) from high normal euthyroidism (incidence rate ratio 1.12 (95% CI 1.03 to 1.21)) to subclinical hyperthyroidism with reduced TSH (1.16 (0.99 to 1.36)) and subclinical hyperthyroidism with supressed TSH (1.41 (1.25 to 1.59)). Both overt and subclinical hypothyroidism were associated with a lower risk of atrial fibrillation. Conclusion The risk of atrial fibrillation was closely associated with thyroid activity, with a low risk in overt hypothyroidism, high risk in hyperthyroidism, and a TSH level dependent association with risk of atrial fibrillation across the spectrum of subclinical thyroid disease. PMID:23186910

Thyroid Storm with Heart Failure Treated with a Short-acting Beta-adrenoreceptor Blocker, Landiolol Hydrochloride.

PubMed

Yamashita, Yugo; Iguchi, Moritake; Nakatani, Rieko; Usui, Takeshi; Takagi, Daisuke; Hamatani, Yasuhiro; Unoki, Takashi; Ishii, Mitsuru; Ogawa, Hisashi; Masunaga, Nobutoyo; Abe, Mitsuru; Akao, Masaharu

2015-01-01

Beta-adrenoreceptor blockers are essential in controlling the peripheral actions of thyroid hormones and a rapid heart rate in patients with thyroid storm, although they should be used with great caution when there is the potential for heart failure. A 67-year-old woman was diagnosed as having thyroid storm in addition to marked tachycardia with atrial fibrillation and heart failure associated with a reduced left ventricular function. The administration of an oral beta blocker, bisoprolol fumarate, induced hypotension and was not tolerable for the patient, whereas landiolol hydrochloride, a short-acting intravenous beta-adrenoreceptor blocker with high cardioselectivity and a short elimination half-life, was useful for controlling the patient's tachycardia and heart failure without causing hemodynamic deterioration.

Thyroid-Stimulating Hormone Receptor Antibodies in Pregnancy: Clinical Relevance

PubMed Central

Bucci, Ines; Giuliani, Cesidio; Napolitano, Giorgio

2017-01-01

Graves’ disease is the most common cause of thyrotoxicosis in women of childbearing age. Approximately 1% of pregnant women been treated before, or are being treated during pregnancy for Graves’ hyperthyroidism. In pregnancy, as in not pregnant state, thyroid-stimulating hormone (TSH) receptor (TSHR) antibodies (TRAbs) are the pathogenetic hallmark of Graves’ disease. TRAbs are heterogeneous for molecular and functional properties and are subdivided into activating (TSAbs), blocking (TBAbs), or neutral (N-TRAbs) depending on their effect on TSHR. The typical clinical features of Graves’ disease (goiter, hyperthyroidism, ophthalmopathy, dermopathy) occur when TSAbs predominate. Graves’ disease shows some peculiarities in pregnancy. The TRAbs disturb the maternal as well as the fetal thyroid function given their ability to cross the placental barrier. The pregnancy-related immunosuppression reduces the levels of TRAbs in most cases although they persist in women with active disease as well as in women who received definitive therapy (radioiodine or surgery) before pregnancy. Changes of functional properties from stimulating to blocking the TSHR could occur during gestation. Drug therapy is the treatment of choice for hyperthyroidism during gestation. Antithyroid drugs also cross the placenta and therefore decrease both the maternal and the fetal thyroid hormone production. The management of Graves’ disease in pregnancy should be aimed at maintaining euthyroidism in the mother as well as in the fetus. Maternal and fetal thyroid dysfunction (hyperthyroidism as well as hypothyroidism) are in fact associated with several morbidities. Monitoring of the maternal thyroid function, TRAbs measurement, and fetal surveillance are the mainstay for the management of Graves’ disease in pregnancy. This review summarizes the biochemical, immunological, and therapeutic aspects of Graves’ disease in pregnancy focusing on the role of the TRAbs in maternal and fetal function. PMID:28713331

Effects of thyroid hormones on the heart.

PubMed

Vargas-Uricoechea, Hernando; Bonelo-Perdomo, Anilsa; Sierra-Torres, Carlos Hernán

2014-01-01

Thyroid hormones have a significant impact on heart function, mediated by genomic and non-genomic effects. Consequently, thyroid hormone deficiencies, as well as excesses, are expected to result in profound changes in cardiac function regulation and cardiovascular hemodynamics. Thyroid hormones upregulate the expression of the sarcoplasmic reticulum calcium-activated ATPase and downregulate the expression of phospholamban. Overall, hyperthyroidism is characterized by an increase in resting heart rate, blood volume, stroke volume, myocardial contractility, and ejection fraction. The development of "high-output heart failure" in hyperthyroidism may be due to "tachycardia-mediated cardiomyopathy". On the other hand, in a hypothyroid state, thyroid hormone deficiency results in lower heart rate and weakening of myocardial contraction and relaxation, with prolonged systolic and early diastolic times. Cardiac preload is decreased due to impaired diastolic function. Cardiac afterload is increased, and chronotropic and inotropic functions are reduced. Subclinical thyroid dysfunction is relatively common in patients over 65 years of age. In general, subclinical hypothyroidism increases the risk of coronary heart disease (CHD) mortality and CHD events, but not of total mortality. The risk of CHD mortality and atrial fibrillation (but not other outcomes) in subclinical hyperthyroidism is higher among patients with very low levels of thyrotropin. Finally, medications such as amiodarone may induce hypothyroidism (mediated by the Wolff-Chaikoff), as well as hyperthyroidism (mediated by the Jod-Basedow effect). In both instances, the underlying cause is the high concentration of iodine in this medication. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

Experimental models of developmental hypothyroidism.

PubMed

Argumedo, G S; Sanz, C R; Olguín, H J

2012-02-01

Hypothyroidism is a systemic disease resulting from either thyroid gland's anatomical and functional absence or lack of hypophyseal stimulation, both of which can lead to deficiency in thyroid hormone (TH) production. TH is essential for human and animal development, growth, and function of multiple organs. Children with deficient TH can develop alterations in central nervous system (CNS), striated muscle, bone tissue, liver, bone marrow, and cardiorespiratory system. Among the clinical outlook are signs like breathing difficulty, cardiac insufficiency, dysphagia, and repeated bronchial aspiration, constipation, muscle weakness, cognitive alterations, cochlear dysfunction, reduced height, defects in temperature regulation, anaemia, jaundice, susceptibility to infection, and others. Experimental and clinical studies have shown that TH is very essential for normal brain development. Other research work based on mice pointed out that a reduced level of TH in pregnant mother leads to congenital hypothyroidism in animal models and it is associated with mental retardation, deep neurologic deficiency that impacts on cognitive, learning, and memory functions. The principal experimental model studies that have focused on hypothyroidism are reviewed in this study. This is important on considering the fact that almost all animal species require thyroid hormones for their metabolism. © Georg Thieme Verlag KG Stuttgart · New York.

Effects of Excess Fluoride and Iodide on Thyroid Function and Morphology.

PubMed

Jiang, Yaqiu; Guo, Xiujuan; Sun, Qiuyan; Shan, Zhongyan; Teng, Weiping

2016-04-01

Exposure to high levels of iodide in Cangzhou, Shandong Province, China has been associated with increased incidence of thyroid disease; however, whether fluoride can affect the thyroid remains controversial. To investigate the effects of excess fluoride, we evaluated thyroid gland structure and function in rats exposed to fluoride and iodide, either alone or in combination. Five-week-old Wistar rats (n = 160 total) were randomly divided into eight groups: three groups that were given excess fluoride (15, 30, or 60 ppm F); one group given excess iodide (1200 μg/L I); three groups given excess iodide plus fluoride (1200 μg/L I plus 15, 30, or 60 ppm F); and one control group. The serum concentrations of the thyroid hormones TT3 and TT4 on day 150 were significantly reduced for certain fluoride groups; however, no significant differences were observed in concentrations for the pituitary hormone TSH among any groups. Hematoxylin and eosin staining revealed that iodide causes an increase in the areas of the colloid lumens and a decrease in the diameters of epithelial cells and nuclei; however, fluoride causes an increase in nuclear diameters. The damage to follicular epithelial cells upon fluoride or iodide treatment was easily observed by transmission electron microscopy, but the effects were most dramatic upon treatment with both fluoride and iodide. These results suggest that iodide causes the most damage but that fluoride can promote specific changes in the function and morphology of the thyroid, either alone or in combination with iodide.

High-intensity focused ultrasound (HIFU) therapy for benign thyroid nodules without anesthesia or sedation.

PubMed

Trimboli, Pierpaolo; Bini, Fabiano; Marinozzi, Franco; Baek, Jung Hwan; Giovanella, Luca

2018-02-16

Thermal ablation of thyroid nodules has gained momentum due to the possibility to avoid surgery. High-intensity focused ultrasound (HIFU) allows thermal treatment by energy ultrasound beam inside the targeted zone. Aim of our study was to evaluate the effects of HIFU treatment using Beamotion mode without anesthesia. Since 2016, patients with normal thyroid function, benign thyroid nodules with diameter no larger than 4 cm, and presenting local discomfort and/or compressive symptoms were treated by HIFU. We performed Beamotion HIFU and did not use anesthesia. Nodule size and thyroid function were evaluated before HIFU and 6 and 12 months later. Complications to therapy and tolerability of patients were also recorded. According to local ethical committee, for this retrospective study formal consent was not required. The final series included 26 nodules from 26 patients with estimated volume of 2.81 ± 2.04 mL, treated by a power of 33.3 ± 10.3 W/site and energy of 2.1 ± 1.1 kJ. Nodules volume was significantly (p < 0.0001) reduced at 6 months of follow-up (1.83 ± 1.63 mL), and further at 1 year (1.57 ± 1.47 mL). Mean percentage of reduction over time of nodules was 48%. A 73% of patients described good comfort during treatment, 100% experienced good comfort just after therapy, and tolerability was high. No complications were recorded. At one 1 year of follow-up, 85% of subjects reported a reduction of local symptoms. HIFU therapy is effective in reducing size of thyroid nodules with major diameter below 4 cm and can be performed without anesthesia.

Functional central hypothyroidism in the elderly.

PubMed

Sell, Maren A; Schott, Matthias; Tharandt, Lutz; Cissewski, Klaus; Scherbaum, Werner A; Willenberg, Holger S

2008-06-01

Previous studies have shown that blood concentrations of free thyroxin and basal thyroid-stimulating hormone (TSH) decrease during adult life. Suggested mechanisms include reduced thyroid activity resulting from decreased serum TSH concentrations, impairment of peripheral 5'-deiodinase, and an increase in reverse 3,5,3'-triiodothyronine due to non-thyroidal illness. However, testing of pituitary reserves leads to contradictory results and has infrequently been evaluated in studies. We investigated whether the response of TSH to thyrotropin-releasing hormone (TRH) is preserved during aging. This was tested in a cohort of 387 subjects aged 13 to 100 years in whom thyroid disease was excluded by normal thyroid ultrasound, normal values for free thyroxin, free triiodothyronin, TSH, and negative thyroid peroxidase antibodies. Serum concentrations of free thyroxin remained almost unchanged, whereas free triiodothyronin and TSH levels were lower in older subjects. In addition, the TSH response to TRH was blunted in older subjects, especially in male individuals. There is evidence that the decreased thyroid hormone levels observed in aging are due to lower TSH concentrations, and that lower TSH concentrations may be linked to an impaired pituitary activity.

Oxidative Stress and Heart Failure in Altered Thyroid States

PubMed Central

Mishra, Pallavi; Samanta, Luna

2012-01-01

Increased or reduced action of thyroid hormone on certain molecular pathways in the heart and vasculature causes relevant cardiovascular derangements. It is well established that hyperthyroidism induces a hyperdynamic cardiovascular state, which is associated with a faster heart rate, enhanced left ventricular systolic and diastolic function whereas hypothyroidism is characterized by the opposite changes. Hyperthyroidism and hypothyroidism represent opposite clinical conditions, albeit not mirror images. Recent experimental and clinical studies have suggested the involvement of ROS tissue damage under altered thyroid status. Altered-thyroid state-linked changes in heart modify their susceptibility to oxidants and the extent of the oxidative damage they suffer following oxidative challenge. Chronic increase in the cellular levels of ROS can lead to a catastrophic cycle of DNA damage, mitochondrial dysfunction, further ROS generation and cellular injury. Thus, these cellular events might play an important role in the development and progression of myocardial remodeling and heart failure in altered thyroid states (hypo- and hyper-thyroidism). The present review aims at elucidating the various signaling pathways mediated via ROS and their modulation under altered thyroid state and the possibility of antioxidant therapy. PMID:22649319

Impact of Triclosan on Female Reproduction through Reducing Thyroid Hormones to Suppress Hypothalamic Kisspeptin Neurons in Mice.

PubMed

Cao, Xin-Yuan; Hua, Xu; Xiong, Jian-Wei; Zhu, Wen-Ting; Zhang, Jun; Chen, Ling

2018-01-01

Triclosan (TCS), a broad-spectrum antimicrobial agent, is widely used in clinical settings and various personal care products. The aim of this study was to evaluate the influence of TCS on reproductive endocrine and function. Here, we show that the exposure of adult female mice to 10 or 100 mg/kg/day TCS caused prolongation of diestrus, and decreases in antral follicles and corpora lutea within 2 weeks. TCS mice showed decreases in the levels of serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and progesterone, and gonadotrophin-releasing hormone ( GnRH ) mRNA with the lack of LH surge and elevation of prolactin (PRL). TCS mice had lower kisspeptin immunoreactivity and kiss1 mRNA in anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC). Moreover, the estrogen (E2)-enhanced AVPV-kisspeptin expression was reduced in TCS mice. In addition, the serum thyroid hormones (triiodothyronine (T3) and thyroxine (T4)) in TCS mice were reduced with increases in levels of thyroid stimulating hormone (TSH) and thyroid releasing hormone (TRH). In TCS mice, the treatment with Levothyroxine (L-T4) corrected the increases in PRL, TSH and TRH; the administration of L-T4 or type-2 dopamine receptors agonist quinpirole inhibiting PRL release could rescue the decline of kisspeptin expression in AVPV and ARC; the treatment with L-T4, quinpirole or the GPR45 agonist kisspeptin-10 recovered the levels of serum LH and FSH and progesterone, and GnRH mRNA. Furthermore, TCS mice treated with L-T4 or quinpirole resumed regular estrous cycling, follicular development and ovulation. Together, these results indicate that exposing adult female mice to TCS (≥10 mg/kg) reduces thyroid hormones causing hyperprolactinemia that then suppresses hypothalamic kisspeptin expression, leading to deficits in reproductive endocrine and function.

Impact of Triclosan on Female Reproduction through Reducing Thyroid Hormones to Suppress Hypothalamic Kisspeptin Neurons in Mice

PubMed Central

Cao, Xin-Yuan; Hua, Xu; Xiong, Jian-Wei; Zhu, Wen-Ting; Zhang, Jun; Chen, Ling

2018-01-01

Triclosan (TCS), a broad-spectrum antimicrobial agent, is widely used in clinical settings and various personal care products. The aim of this study was to evaluate the influence of TCS on reproductive endocrine and function. Here, we show that the exposure of adult female mice to 10 or 100 mg/kg/day TCS caused prolongation of diestrus, and decreases in antral follicles and corpora lutea within 2 weeks. TCS mice showed decreases in the levels of serum luteinizing hormone (LH), follicle-stimulating hormone (FSH) and progesterone, and gonadotrophin-releasing hormone (GnRH) mRNA with the lack of LH surge and elevation of prolactin (PRL). TCS mice had lower kisspeptin immunoreactivity and kiss1 mRNA in anteroventral periventricular nucleus (AVPV) and arcuate nucleus (ARC). Moreover, the estrogen (E2)-enhanced AVPV-kisspeptin expression was reduced in TCS mice. In addition, the serum thyroid hormones (triiodothyronine (T3) and thyroxine (T4)) in TCS mice were reduced with increases in levels of thyroid stimulating hormone (TSH) and thyroid releasing hormone (TRH). In TCS mice, the treatment with Levothyroxine (L-T4) corrected the increases in PRL, TSH and TRH; the administration of L-T4 or type-2 dopamine receptors agonist quinpirole inhibiting PRL release could rescue the decline of kisspeptin expression in AVPV and ARC; the treatment with L-T4, quinpirole or the GPR45 agonist kisspeptin-10 recovered the levels of serum LH and FSH and progesterone, and GnRH mRNA. Furthermore, TCS mice treated with L-T4 or quinpirole resumed regular estrous cycling, follicular development and ovulation. Together, these results indicate that exposing adult female mice to TCS (≥10 mg/kg) reduces thyroid hormones causing hyperprolactinemia that then suppresses hypothalamic kisspeptin expression, leading to deficits in reproductive endocrine and function. PMID:29403355

Resistance to thyroid hormone due to defective thyroid receptor alpha.

PubMed

Moran, Carla; Chatterjee, Krishna

2015-08-01

Thyroid hormones act via nuclear receptors (TRα1, TRβ1, TRβ2) with differing tissue distribution; the role of α2 protein, derived from the same gene locus as TRα1, is unclear. Resistance to thyroid hormone alpha (RTHα) is characterised by tissue-specific hypothyroidism associated with near-normal thyroid function tests. Clinical features include dysmorphic facies, skeletal dysplasia (macrocephaly, epiphyseal dysgenesis), growth retardation, constipation, dyspraxia and intellectual deficit. Biochemical abnormalities include low/low-normal T4 and high/high-normal T3 concentrations, a subnormal T4/T3 ratio, variably reduced reverse T3, raised muscle creatine kinase and mild anaemia. The disorder is mediated by heterozygous, loss-of-function, mutations involving either TRα1 alone or both TRα1 and α2, with no discernible phenotype attributable to defective α2. Whole exome sequencing and diagnostic biomarkers may enable greater ascertainment of RTHα, which is important as thyroxine therapy reverses some metabolic abnormalities and improves growth, constipation, dyspraxia and wellbeing. The genetic and phenotypic heterogeneity of RTHα and its optimal management remain to be elucidated. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Leptin, NPY, Melatonin and Zinc Levels in Experimental Hypothyroidism and Hyperthyroidism: The Relation to Zinc.

PubMed

Baltaci, Abdulkerim Kasım; Mogulkoc, Rasim

2017-06-01

Since zinc mediates the effects of many hormones or is found in the structure of numerous hormone receptors, zinc deficiency leads to various functional impairments in the hormone balance. And also thyroid hormones have important activity on metabolism and feeding. NPY and leptin are affective on food intake and regulation of appetite. The present study is conducted to determine how zinc supplementation and deficiency affect thyroid hormones (free and total T3 and T4), melatonin, leptin, and NPY levels in thyroid dysfunction in rats. The experiment groups in the study were formed as follows: Control (C); Hypothyroidism (PTU); Hypothyroidism+Zinc (PTU+Zn); Hypothyroidism+Zinc deficient; Hyperthyroidism (H); Hyperthyroidism+Zinc (H+Zn); and Hyperthyroidism+Zinc deficient. Thyroid hormone parameters (FT 3 , FT 4 , TT 3 , and TT 4 ) were found to be reduced in hypothyroidism groups and elevated in the hyperthyroidism groups. Melatonin values increased in hyperthyroidism and decreased in hypothyroidism. Leptin and NPY levels both increased in hypo- and hyperthyroidism. Zinc levels, on the other hand, decreased in hypothyroidism and increased in hyperthyroidism. Zinc supplementation, particularly when thyroid function is impaired, has been demonstrated to markedly prevent these changes.

Effects of a 5-day treatment with the UV-filter octyl-methoxycinnamate (OMC) on the function of the hypothalamo-pituitary-thyroid function in rats.

PubMed

Klammer, Holger; Schlecht, Christiane; Wuttke, Wolfgang; Schmutzler, Cornelia; Gotthardt, Inka; Köhrle, Josef; Jarry, Hubertus

2007-09-05

Octyl-methoxycinnamate (OMC) is one of the most frequently used UV-filters in sunscreens to protect the skin against the noxious influence of UV radiation. Recently, OMC was suspected to act as an "endocrine active chemical" (EAC) with estrogenic actions. While EACs have been investigated thoroughly for interference with reproductive function in mammalians, surprisingly little efforts have been made to investigate an interference of EACs with the hypothalamo-pituitary-thyroid (HPT) axis despite the expression of estrogen receptors in all parts of this axis. Therefore, we conducted an in vivo study with ovariectomised rats treated for 5 days with different doses of OMC or 17beta-estradiol (E2) as a control. Determined parameters comprised serum levels of TSH, T4 and T3, hypothalamic TRH mRNA expression, protein-expression of the sodium-iodide-symporter (NIS) and the TSH receptor and the activities of thyroid peroxidase (TPO) in the thyroid and the T3-responsive hepatic type I 5'deiodinase (Dio1) in the liver. While E2 did not affect TSH-, T4- or T3-levels, OMC caused a dose-dependent decrease of serum concentrations of all of these hormones. TRH expression remained unaffected, while in the thyroid, expression of the TSH receptor but not of NIS was stimulated by OMC. TPO activity was unaltered but Dio1 activity was reduced by OMC. Thus, our results demonstrate a non-estrogenic interference of OMC within the rodent HPT axis with inadequate feedback response to impaired thyroid hormone status, indicated by decreased serum thyroid hormone and hepatic Dio1 levels.

Identification of thyroid tumor cell vulnerabilities through a siRNA-based functional screening.

PubMed

Anania, Maria; Gasparri, Fabio; Cetti, Elena; Fraietta, Ivan; Todoerti, Katia; Miranda, Claudia; Mazzoni, Mara; Re, Claudia; Colombo, Riccardo; Ukmar, Giorgio; Camisasca, Stefano; Pagliardini, Sonia; Pierotti, Marco; Neri, Antonino; Galvani, Arturo; Greco, Angela

2015-10-27

The incidence of thyroid carcinoma is rapidly increasing. Although generally associated with good prognosis, a fraction of thyroid tumors are not cured by standard therapy and progress to aggressive forms for which no effective treatments are currently available. In order to identify novel therapeutic targets for thyroid carcinoma, we focused on the discovery of genes essential for sustaining the oncogenic phenotype of thyroid tumor cells, but not required to the same degree for the viability of normal cells (non-oncogene addiction paradigm). We screened a siRNA oligonucleotide library targeting the human druggable genome in thyroid cancer BCPAP cell line in comparison with immortalized normal human thyrocytes (Nthy-ori 3-1). We identified a panel of hit genes whose silencing interferes with the growth of tumor cells, while sparing that of normal ones. Further analysis of three selected hit genes, namely Cyclin D1, MASTL and COPZ1, showed that they represent common vulnerabilities for thyroid tumor cells, as their inhibition reduced the viability of several thyroid tumor cell lines, regardless the histotype or oncogenic lesion. This work identified non-oncogenes essential for sustaining the phenotype of thyroid tumor cells, but not of normal cells, thus suggesting that they might represent promising targets for new therapeutic strategies.

[Thyroid hormones and the development of the nervous system].

PubMed

Mussa, G C; Zaffaroni, M; Mussa, F

1990-09-01

The growth and differentiation of the central nervous system are closely related to the presence of iodine and thyroid hormones. During the first trimester of human pregnancy the development of the nervous system depends entirely on the availability of iodine; after 12 week of pregnancy it depends on the initial secretion of iodothyronine by the fetal thyroid gland. During the early stages of the development of the nervous system a thyroid hormone deficit may provoke alterations in the maturation of both noble nervous cells (cortical pyramidal cells, Purkinje cells) and glial cells. Hypothyroidism may lead to cellular hypoplasia and reduced dendritic ramification, gemmules and interneuronal connections. Experimental studies in hypothyroid rats have also shown alterations in the content and organization of neuronal intracytoplasmatic microtubules, the biochemical maturation of synaptosomes and the maturation of nuclear and cytoplasmatic T3 receptors. Excess thyroid hormones during the early stages of development may also cause permanent damage to the central nervous system. Hyperthyroidism may initially induce an acceleration of the maturation processes, including the migration and differentiation of cells, the extension of the dendritic processes and synaptogenesis. An excess of thyroid hormones therefore causes neuronal proliferation to end precociously leading to a reduction of the total number of gemmules. Experimental research and clinical studies have partially clarified the correlation between the maturation of the nervous system and thyroid function during the early stages of development; both a deficit and excess of thyroid hormones may lead to permanent anatomo-functional damage to the central nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)

[The effect of arotinolol on the thyroid function and the autonomic nerve systems].

PubMed

Fukasawa, N; Iitaka, M; Kitahama, S; Miura, S; Sakurai, S; Kawakami, Y; Ishii, J

1993-01-20

beta-blockers have been accepted as a reasonable adjunct therapy for the treatment of hyperthyroidism. They lessen the sympathetic symptoms such as tachycardia and finger tremor. On the other hand, many studies have demonstrated a decrease in 3, 3', 5-triiodothyronine (T3) during treatment with beta-blockers (especially propranolol). The purpose of this study is to clarify the effect of arotinolol (alpha 1, beta-blocker) on the thyroid functions and autonomic nerve systems (ANS) of patients with Graves' disease. Arotinolol 20mg a day p.o. was given to untreated patients with Graves' disease (n = 16) for 2 weeks. Blood sampling and the ANS function-tests were done before and after the treatment. In addition, the in vitro effects of arotinolol on the cAMP production and the radioactive iodine uptake (RAIU) using rat thyroid cell line FRTL5 were evaluated to examine the direct influence on thyroid cells. Arotinolol improved hyperthyroid symptoms including tachycardia, but had no effect on ANS function-tests. It is of interest that not only T3 but also T4 decreased after the arotinolol treatment. We therefore suspected the direct suppressive effects of arotinolol on the thyroid. There were, however, no in vitro inhibitory effects on the cAMP production and the RAIU in TSH-stimulated FRTL5 cells. The reason why serum T4 levels in patients with untreated Graves' disease have decreased after the treatment of arotinolol could not be clarified. In conclusion, arotinolol is a very useful drug for the initial therapy of patients with Graves' disease to reduce the serum thyroid hormone levels and symptoms of hyperthyroidism when combined with antithyroid drugs.

Recurrent pregnancy loss in patients with thyroid dysfunction.

PubMed

Sarkar, Debanjali

2012-12-01

Thyroid disturbances are common in women during their reproductive years. Thyroid dysfunction interferes with human reproductive physiology, reduces the likelihood of pregnancy and adversely affects pregnancy outcome, thus becoming relevant in the algorithm of reproductive dysfunction. This review highlights the gap in knowledge regarding the contribution of thyroid dysfunction in reproduction. Following implantation, the maintenance of the pregnancy is dependent on a multitude of endocrinological events that will eventually aid in the successful growth and development of the fetus. It is estimated that approximately 8-12% of all pregnancy losses are the result of endocrine factors. Autoimmune thyroid disease is present in around 4% of young females and up to 15% are at risk because they are thyroid antibody-positive. There is a strong relationship between thyroid immunity on one hand and infertility, miscarriage, and thyroid disturbances in pregnancy and postpartum, on the other hand. Even minimal hypothyroidism can increase rates of miscarriage and fetal death and may also have adverse effects on later cognitive development of the offspring. Hyperthyroidism during pregnancy may also have adverse consequences. Pregnant women with subclinical hypothyroidism or thyroid antibodies have an increased risk of complications, especially pre-eclampsia, perinatal mortality, and miscarriage. Universal screening for thyroid hormone abnormalities is not routinely recommended at present, but thyroid function must be examined in female with fetal loss or menstrual disturbances. Practitioners providing health care for women should be alert to thyroid disorders as an underlying etiology for recurrent pregnancy loss.

The heterochronic gene Lin28 regulates amphibian metamorphosis through disturbance of thyroid hormone function.

PubMed

Faunes, Fernando; Gundermann, Daniel G; Muñoz, Rosana; Bruno, Renzo; Larraín, Juan

2017-05-15

Metamorphosis is a classic example of developmental transition, which involves important morphological and physiological changes that prepare the organism for the adult life. It has been very well established that amphibian metamorphosis is mainly controlled by Thyroid Hormone (TH). Here, we show that the heterochronic gene Lin28 is downregulated during Xenopus laevis metamorphosis. Lin28 overexpression before activation of TH signaling delays metamorphosis and inhibits the expression of TH target genes. The delay in metamorphosis is rescued by incubation with exogenous TH, indicating that Lin28 works upstream or parallel to TH. High-throughput analyses performed before any delay on metamorphosis or change in TH signaling showed that overexpression of Lin28 reduces transcript levels of several hormones secreted by the pituitary, including the Thyroid-Stimulating Hormone (TSH), and regulates the expression of proteins involved in TH transport, metabolism and signaling, showing that Lin28 disrupts TH function at different levels. Our data demonstrates that the role of Lin28 in controlling developmental transitions is evolutionary conserved and establishes a functional interaction between Lin28 and thyroid hormone function introducing a new regulatory step in perinatal development with implications for our understanding of endocrine disorders. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Effectiveness of interventions to reduce ordering of thyroid function tests: a systematic review.

PubMed

Zhelev, Zhivko; Abbott, Rebecca; Rogers, Morwenna; Fleming, Simon; Patterson, Anthea; Hamilton, William Trevor; Heaton, Janet; Thompson Coon, Jo; Vaidya, Bijay; Hyde, Christopher

2016-06-03

To evaluate the effectiveness of behaviour changing interventions targeting ordering of thyroid function tests. Systematic review. MEDLINE, EMBASE and the Cochrane Database up to May 2015. We included studies evaluating the effectiveness of behaviour change interventions aiming to reduce ordering of thyroid function tests. Randomised controlled trials (RCTs), non-randomised controlled studies and before and after studies were included. There were no language restrictions. 2 reviewers independently screened all records identified by the electronic searches and reviewed the full text of any deemed potentially relevant. Study details were extracted from the included papers and their methodological quality assessed independently using a validated tool. Disagreements were resolved through discussion and arbitration by a third reviewer. Meta-analysis was not used. 27 studies (28 papers) were included. They evaluated a range of interventions including guidelines/protocols, changes to funding policy, education, decision aids, reminders and audit/feedback; often intervention types were combined. The most common outcome measured was the rate of test ordering, but the effect on appropriateness, test ordering patterns and cost were also measured. 4 studies were RCTs. The majority of the studies were of poor or moderate methodological quality. The interventions were variable and poorly reported. Only 4 studies reported unsuccessful interventions but there was no clear pattern to link effect and intervention type or other characteristics. The results suggest that behaviour change interventions are effective particularly in reducing the volume of thyroid function tests. However, due to the poor methodological quality and reporting of the studies, the likely presence of publication bias and the questionable relevance of some interventions to current day practice, we are unable to draw strong conclusions or recommend the implementation of specific intervention types. Further research is thus justified. CRD42014006192. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Effectiveness of interventions to reduce ordering of thyroid function tests: a systematic review

PubMed Central

Abbott, Rebecca; Rogers, Morwenna; Fleming, Simon; Patterson, Anthea; Hamilton, William Trevor; Heaton, Janet; Vaidya, Bijay; Hyde, Christopher

2016-01-01

Objectives To evaluate the effectiveness of behaviour changing interventions targeting ordering of thyroid function tests. Design Systematic review. Data sources MEDLINE, EMBASE and the Cochrane Database up to May 2015. Eligibility criteria for selecting studies We included studies evaluating the effectiveness of behaviour change interventions aiming to reduce ordering of thyroid function tests. Randomised controlled trials (RCTs), non-randomised controlled studies and before and after studies were included. There were no language restrictions. Study appraisal and synthesis methods 2 reviewers independently screened all records identified by the electronic searches and reviewed the full text of any deemed potentially relevant. Study details were extracted from the included papers and their methodological quality assessed independently using a validated tool. Disagreements were resolved through discussion and arbitration by a third reviewer. Meta-analysis was not used. Results 27 studies (28 papers) were included. They evaluated a range of interventions including guidelines/protocols, changes to funding policy, education, decision aids, reminders and audit/feedback; often intervention types were combined. The most common outcome measured was the rate of test ordering, but the effect on appropriateness, test ordering patterns and cost were also measured. 4 studies were RCTs. The majority of the studies were of poor or moderate methodological quality. The interventions were variable and poorly reported. Only 4 studies reported unsuccessful interventions but there was no clear pattern to link effect and intervention type or other characteristics. Conclusions The results suggest that behaviour change interventions are effective particularly in reducing the volume of thyroid function tests. However, due to the poor methodological quality and reporting of the studies, the likely presence of publication bias and the questionable relevance of some interventions to current day practice, we are unable to draw strong conclusions or recommend the implementation of specific intervention types. Further research is thus justified. Trial registration number CRD42014006192. PMID:27259523

[Clinical features of myasthenia gravis with thyroid disease with 106 patients].

PubMed

Meng, Chao; Jing, Yun; Li, Ran; Zhang, Xiaojun; Wang, Jiawei

2016-03-22

To report the presentation, clinical course and prognosis of myasthenia gravis (MG) with thyroid disease. Retrospective data analysis was conducted.Between 2004 and 2013, we reviewed a total of 106 patients with MG. We analyzed the clinical features, the relationship between the thyroid function, antibodies and the clinical course, prognosis. (1) In our study, 20/106 (18.87%) patients were thyroid function-abnormal, 37/106 (34.91) were thyroglobulin antibodies (TGAb) and/or thyroid microsomal antibody (TMAb)-positive, and abnormality was observed in 46 (43.40%) of the thyroid gland. Thyroid antibody positive rate was higher than abnormal thyroid function rate, and the difference was significant (P=0.036). (2) The thyroid stimulating hormone (TSH) level ((2.9±4.0) mIU/L) of ocular MG was higher than the level ((1.5±1.1) mIU/L) of generalized MG (P=0.01). (3) The transformation time of 52 ocular type to generalized type was longer in higher antibody group than in normal group (P=0.04). And there were no significant differences between the elevated TSH type and the normal TSH type, the abnormal thyroid function type and normal thyroid function type, the abnormal thyroid type and the normal thyroid type. (4) Comparing the TSH level, total antibody level, TGAb, and TMAb level between the ease group and the unease group in the course of 1 year, 2 years, 5 years, there were no significant differences (all P>0.05). MG is often companied with thyroid abnormalities. MG patients are more susceptible to hashimoto thyroiditis and other autoimmune thyroid diseases. Ocular type patients are more likely to suffer from thyroid function decrease than the generalized type. MG patients with hashimoto thyroiditis and other autoimmune thyroid diseases are more sensitive to respond to therapy means like glucocorticoid therapy, and the short-term prognosis is relatively good. There are no significant correlations between the MG remission rate and TSH level, total antibody level, TGAb and TMAb level.

Exposure of xenopus laevis tadpoles to cadmium reveals concentration-dependent bimodal effects on growth and monotonic effects on development and thyroid gland activity

USGS Publications Warehouse

Sharma, Bibek; Patino, R.

2008-01-01

Xenopus laevis were exposed to 0-855 ??g cadmium (Cd)/l (measured concentrations) in FETAX medium from fertilization to 47 days postfertilization. Measurements included embryonic survival and, at 47 days, tadpole survival, snout-vent length, tail length, total length, hindlimb length, weight, Nieuwkoop-Faber (NF) stage of development, initiation of metamorphic climax (??? NF 58), and thyroid follicle cell height. Embryonic and larval survival were unaffected by Cd. Relative to control tadpoles, reduced tail and total length were observed at 0.1- 8 and at 855 ??g Cd/l; and reduced snout-vent length, hindlimb length, and weight were observed at 0.1-1 and at 855 ??g Cd/l. Mean stage of development and rate of initiation of climax were unaffected by Cd at 0-84 ??g/l; however, none of the tadpoles exposed to 855 ??g Cd/l progressed beyond mid-premetamorphosis (NF 51). Thyroid glands with fully formed follicles were observed in all tadpoles ??? NF 49 examined. Follicle cell height was unaffected by Cd at 0-84 ??g/l but it was reduced at 855 ??g/l; in the latter, cell height was reduced even when compared with NF 49-51 tadpoles pooled from the 0 to 84 ??g Cd/l groups. In conclusion, (1) Cd affected tadpole growth in a bimodal pattern with the first and second inhibitory modes at concentrations below and above 84 ??g Cd/l, respectively; (2) exposure to high Cd concentrations (855 ??g/l) reduced thyroid activity and arrested tadpole development at mid-premetamorphosis; and (3) unlike its effect on growth, Cd inhibited tadpole development and thyroid function in a seemingly monotonic pattern.

Effects of Chronic Exposure to an Environmentally Relevant Mixture of Brominated Flame Retardants on the Reproductive and Thyroid System in Adult Male Rats

PubMed Central

Ernest, Sheila R.; Wade, Michael G.; Lalancette, Claudia; Ma, Yi-Qian; Berger, Robert G.; Robaire, Bernard; Hales, Barbara F.

2012-01-01

Brominated flame retardants (BFRs) are incorporated into a wide variety of consumer products, are readily released into home and work environments, and are present in house dust. Studies using animal models have revealed that exposure to polybrominated diphenyl ethers (PBDEs) may impair adult male reproductive function and thyroid hormone physiology. Such studies have generally characterized the outcome of acute or chronic exposure to a single BFR technical mixture or congener but not the impact of environmentally relevant BFR mixtures. We tested whether exposure to the BFRs found in house dust would have an adverse impact on the adult male rat reproductive system and thyroid function. Adult male Sprague Dawley rats were exposed to a complex BFR mixture composed of three commercial brominated diphenyl ethers (52.1% DE-71, 0.4% DE-79, and 44.2% decaBDE-209) and hexabromocyclododecane (3.3%), formulated to mimic the relative congener levels in house dust. BFRs were delivered in the diet at target doses of 0, 0.02, 0.2, 2, or 20 mg/kg/day for 70 days. Compared with controls, males exposed to the highest dose of BFRs displayed a significant increase in the weights of the kidneys and liver, which was accompanied by induction of CYP1A and CYP2B P450 hepatic drug–metabolizing enzymes. BFR exposure did not affect reproductive organ weights, serum testosterone levels, testicular function, or sperm DNA integrity. The highest dose caused thyroid toxicity as indicated by decreased serum thyroxine (T4) and hypertrophy of the thyroid gland epithelium. At lower doses, the thickness of the thyroid gland epithelium was reduced, but no changes in hormone levels (T4 and thyroid-stimulating hormone) were observed. Thus, exposure to BFRs affected liver and thyroid physiology but not male reproductive parameters. PMID:22387749

The thyroid axis in ageing.

PubMed

Leitol, Holger; Behrends, Jens; Brabant, Georg

2002-01-01

The hypothalmo-pituitary thyroid axis, among various endocrine systems, undergoes physiological alterations associated with the ageing process. Directly age-related changes have to be distinguished from indirect modifications which are caused by simultaneous thyroidal or non-thyroidal illness or other physiological or pathophysiological states whose incidence increases with age. In summary, direct changes of the hypothalmo-pituitary-thyroid axis seem to be subtle and suggestive of a decreased hypothalamic stimulation of thyroid function. In parallel, disease-specific alterations such as the development of thyroid autonomy or changes in energy intake or sleep lead to pronounced alterations of thyroid function with age which may dominate the underlying ageing of the hypothalmo-pituitary thyroid axis itself. The following article attempts to delineate some aspects of the interplay of the regulation of thyroid function and the ageing process.

Fetal and Neonatal Iron Deficiency Exacerbates Mild Thyroid Hormone Insufficiency Effects on Male Thyroid Hormone Levels and Brain Thyroid Hormone-Responsive Gene Expression

PubMed Central

Bastian, Thomas W.; Prohaska, Joseph R.; Georgieff, Michael K.

2014-01-01

Fetal/neonatal iron (Fe) and iodine/TH deficiencies lead to similar brain developmental abnormalities and often coexist in developing countries. We recently demonstrated that fetal/neonatal Fe deficiency results in a mild neonatal thyroidal impairment, suggesting that TH insufficiency contributes to the neurodevelopmental abnormalities associated with Fe deficiency. We hypothesized that combining Fe deficiency with an additional mild thyroidal perturbation (6-propyl-2-thiouracil [PTU]) during development would more severely impair neonatal thyroidal status and brain TH-responsive gene expression than either deficiency alone. Early gestation pregnant rats were assigned to 7 different treatment groups: control, Fe deficient (FeD), mild TH deficient (1 ppm PTU), moderate TH deficient (3 ppm PTU), severe TH deficient (10 ppm PTU), FeD/1 ppm PTU, or FeD/3 ppm PTU. FeD or 1 ppm PTU treatment alone reduced postnatal day 15 serum total T4 concentrations by 64% and 74%, respectively, without significantly altering serum total T3 concentrations. Neither treatment alone significantly altered postnatal day 16 cortical or hippocampal T3 concentrations. FeD combined with 1 ppm PTU treatment produced a more severe effect, reducing serum total T4 by 95%, and lowering hippocampal and cortical T3 concentrations by 24% and 31%, respectively. Combined FeD/PTU had a more severe effect on brain TH-responsive gene expression than either treatment alone, significantly altering Pvalb, Dio2, Mbp, and Hairless hippocampal and/or cortical mRNA levels. FeD/PTU treatment more severely impacted cortical and hippocampal parvalbumin protein expression compared with either individual treatment. These data suggest that combining 2 mild thyroidal insults during development significantly disrupts thyroid function and impairs TH-regulated brain gene expression. PMID:24424046

Methamphetamine-associated dysregulation of the hypothalamic-pituitary-thyroid axis.

PubMed

Jones, Deborah L; Carrico, Adam W; Babayigit, Suat; Rodriguez, Violeta J; Aguila, Carlos; Kumar, Mahendra

2018-05-17

Methamphetamine and HIV impair thyroid function, but few studies have investigated their combined effects on thyroid dysregulation. This study examined the associations of methamphetamine use alone and in combination with HIV on thyroid function among men in South Florida. Measures of thyroid function in methamphetamine-using, HIV-infected (METH+HIV+; n = 127) and HIV-negative (METH+HIV-; n = 46) men who have sex with men (MSM) were compared to non-methamphetamine-using, HIV-negative men (METH-HIV-; n = 136). Thyroid function was dysregulated in methamphetamine-using MSM, irrespective of HIV status. Both meth-using groups had greater odds of abnormal thyroid stimulating hormone levels and significantly higher mean free triiodothyronine (T3) levels. Elevated free T3 was associated with greater depressive symptoms. Overall, outcomes have important implications for assessment of thyroid function in methamphetamine users, particularly among those presenting with depression.

Iodide Protects Heart Tissue from Reperfusion Injury

PubMed Central

Iwata, Akiko; Morrison, Michael L.; Roth, Mark B.

2014-01-01

Iodine is an elemental nutrient that is essential for mammals. Here we provide evidence for an acute therapeutic role for iodine in ischemia reperfusion injury. Infusion of the reduced form, iodide, but not the oxidized form iodate, reduces heart damage by as much as 75% when delivered intravenously following temporary loss of blood flow but prior to reperfusion of the heart in a mouse model of acute myocardial infarction. Normal thyroid function may be required because loss of thyroid activity abrogates the iodide benefit. Given the high degree of protection and the high degree of safety, iodide should be explored further as a therapy for reperfusion injury. PMID:25379708

[Effects of maternal hyperthyroidism and antithyroid drug therapy on thyroid function of newborn infants].

PubMed

Lian, Xiao-lan; Bai, Yao; Xun, Yun-hua; Dai, Wei-xin; Guo, Zhi-sheng

2005-12-01

To evaluate the relationship between the incidence of abnormal thyroid function of newborns and maternal hyperthyroidism with antithyroid drug therapy. The clinical data of 35 neonates born to mothers with hyperthyroidism from 1983 to 2003 in Peking Union Medical College Hospital were retrospectively analyzed. According to the maternal thyroid function and the antithyroid drugs taken during pregnancy, subjects were divided into different groups. The proportion of abnormal thyroid function in newborn was 48.6% (17/35). The prevalences of primary hypothyroidism, subclinical hypothyroidism, hypothyroxinemia, and central hypothyroidism were 29.4%, 29.4%, 35.3%, and 5.9%, respectively. The incidence of abnormal thyroid function of neonates whose mothers did not take the antithyroid drugs (ATDs) until the third trimester of pregnancy was significantly higher than those without and with ATDs during the first or second trimester (P < 0.01). The incidence of abnormal thyroid function significantly increased in premature neonates, neonates whose mothers with modest or heavy pregnant hypertension, or neonates whose core serum thyroid-stimulating hormone or serum anti-thyroid peroxidase antibodies levels were abnormal. The risk of abnormal thyroid function of infants whose hyperthyroid mothers did not take ATDs until the third trimester of pregnancy may be increased. Prompt diagnosis and appropriate treatment of hyperthyroidism in pregnant women are essential for the prevention of neonatal thyroid functional abnormality.

Hes1 Is Required for Appropriate Morphogenesis and Differentiation during Mouse Thyroid Gland Development

PubMed Central

Carre, Aurore; Rachdi, Latif; Tron, Elodie; Richard, Bénédicte; Castanet, Mireille; Schlumberger, Martin; Bidart, Jean-Michel

2011-01-01

Notch signalling plays an important role in endocrine development, through its target gene Hes1. Hes1, a bHLH transcriptional repressor, influences progenitor cell proliferation and differentiation. Recently, Hes1 was shown to be expressed in the thyroid and regulate expression of the sodium iodide symporter (Nis). To investigate the role of Hes1 for thyroid development, we studied thyroid morphology and function in mice lacking Hes1. During normal mouse thyroid development, Hes1 was detected from E9.5 onwards in the median anlage, and at E11.5 in the ultimobranchial bodies. Hes1 −/− mouse embryos had a significantly lower number of Nkx2-1-positive progenitor cells (p<0.05) at E9.5 and at E11.5. Moreover, Hes1 −/− mouse embryos showed a significantly smaller total thyroid surface area (−40 to −60%) compared to wild type mice at all study time points (E9.5−E16.5). In both Hes1 −/− and wild type mouse embryos, most Nkx2-1-positive thyroid cells expressed the cell cycle inhibitor p57 at E9.5 in correlation with low proliferation index. In Hes1 −/− mouse embryos, fusion of the median anlage with the ultimobranchial bodies was delayed by 3 days (E16.5 vs. E13.5 in wild type mice). After fusion of thyroid anlages, hypoplastic Hes1 −/− thyroids revealed a significantly decreased labelling area for T4 (−78%) and calcitonin (−65%) normalized to Nkx2-1 positive cells. Decreased T4-synthesis might be due to reduced Nis labelling area (−69%). These findings suggest a dual role of Hes1 during thyroid development: first, control of the number of both thyrocyte and C-cell progenitors, via a p57-independent mechanism; second, adequate differentiation and endocrine function of thyrocytes and C-cells. PMID:21364918

Ultrasound-guided microwave ablation in the treatment of benign thyroid nodules in 435 patients

PubMed Central

Qian, Lin-Xue; Liu, Dong; Zhao, Jun-Feng

2017-01-01

The objective of the present study was to investigate the effectiveness and safety of ultrasound-guided microwave ablation in the treatment of benign thyroid nodules. A total of 474 benign thyroid nodules in 435 patients who underwent ultrasound-guided microwave ablation from September 2012 to August 2015 were included. Nodule volume and thyroid function were measured before treatment and at 1, 3, 6, and 12 months and subsequently after every 6 months. The nodule volume reduction rate and changes of thyroid function were evaluated. The volume of all thyroid nodules significantly decreased after ultrasound-guided microwave ablation. The average volume was 13.07 ± 0.95 ml before treatment, and 1.14 ± 0.26 ml at 12-months follow-up. The mean volume reduction rate was 90% and the final volume reduction rate was 94%. The volume reduction rate of mainly cystic nodules was significantly higher than that of simple solid and mainly solid nodules (all P < 0.05). The pretreatment volume of nodules was positively correlated with the final volume reduction rate at final follow-up (P = 0.004). No serious complications were observed after treatment. In conclusion, ultrasound-guided microwave ablation is an effective and safe technique for treatment of benign thyroid nodules, and has the potential for clinical applications. Impact statement Ultrasound-guided MWA is an effective and safe technique for the treatment of benign thyroid nodules. It can significantly reduce the nodule volume, improve the patients’ clinical symptoms, has less complication, guarantees quick recovery, meets patients' aesthetic needs, and shows less interference on the physiological and psychological aspects of the body. MWA should be a good complement to traditional open surgery and has potentials in clinical applications. PMID:28847173

Ultrasound-guided microwave ablation in the treatment of benign thyroid nodules in 435 patients.

PubMed

Liu, Yu-Jiang; Qian, Lin-Xue; Liu, Dong; Zhao, Jun-Feng

2017-09-01

The objective of the present study was to investigate the effectiveness and safety of ultrasound-guided microwave ablation in the treatment of benign thyroid nodules. A total of 474 benign thyroid nodules in 435 patients who underwent ultrasound-guided microwave ablation from September 2012 to August 2015 were included. Nodule volume and thyroid function were measured before treatment and at 1, 3, 6, and 12 months and subsequently after every 6 months. The nodule volume reduction rate and changes of thyroid function were evaluated. The volume of all thyroid nodules significantly decreased after ultrasound-guided microwave ablation. The average volume was 13.07 ± 0.95 ml before treatment, and 1.14 ± 0.26 ml at 12-months follow-up. The mean volume reduction rate was 90% and the final volume reduction rate was 94%. The volume reduction rate of mainly cystic nodules was significantly higher than that of simple solid and mainly solid nodules (all P < 0.05). The pretreatment volume of nodules was positively correlated with the final volume reduction rate at final follow-up ( P = 0.004). No serious complications were observed after treatment. In conclusion, ultrasound-guided microwave ablation is an effective and safe technique for treatment of benign thyroid nodules, and has the potential for clinical applications. Impact statement Ultrasound-guided MWA is an effective and safe technique for the treatment of benign thyroid nodules. It can significantly reduce the nodule volume, improve the patients' clinical symptoms, has less complication, guarantees quick recovery, meets patients' aesthetic needs, and shows less interference on the physiological and psychological aspects of the body. MWA should be a good complement to traditional open surgery and has potentials in clinical applications.

Variants and pitfalls on radioiodine scans in pediatric patients with differentiated thyroid carcinoma.

PubMed

Mostafa, Mohamed; Vali, Reza; Chan, Jeffrey; Omarkhail, Yusuaf; Shammas, Amer

2016-10-01

Potentially false-positive findings on radioiodine scans in children with differentiated thyroid carcinoma can mimic functioning thyroid tissue and functioning thyroid carcinomatous tissue. Such false-positive findings comprise variants and pitfalls that can vary slightly in children as compared with adults. To determine the patterns and frequency of these potential false-positive findings on radioiodine scans in children with differentiated thyroid carcinoma. We reviewed a total of 223 radioiodine scans from 53 pediatric patients (mean age 13.3 years, 37 girls) with differentiated thyroid carcinoma. Focal or regional activity that likely did not represent functioning thyroid tissue or functioning thyroid carcinomatous tissue were categorized as variants or pitfalls. The final diagnosis was confirmed by reviewing the concurrent and follow-up clinical data, correlative ultrasonography, CT scanning, serum thyroglobulin and antithyroglobulin antibody levels. We calculated the frequency of these variants and pitfalls from diagnostic and post-therapy radioiodine scans. The most common variant on the radioiodine scans was the thymic activity (24/223, 10.8%) followed by the cardiac activity (8/223, 3.6%). Salivary contamination and star artifact, caused by prominent thyroid remnant, were the most important observed pitfalls. Variants and pitfalls that mimic functioning thyroid tissue or functioning thyroid carcinomatous tissue on radioiodine scan in children with differentiated thyroid carcinoma are not infrequent, but they decrease in frequency on successive radioiodine scans. Potential false-positive findings can be minimized with proper knowledge of the common variants and pitfalls in children and correlation with clinical, laboratory and imaging data.

Differentiated thyroid carcinoma with functional autonomy.

PubMed

Yaturu, Subhashini; Fowler, Marjorie R

2002-01-01

To present a case of papillary carcinoma in an autonomously hyperfunctioning thyroid nodule. We chronicle the clinical and laboratory findings in a patient with a painless neck mass, with a particular focus on the pathologic findings after surgical removal of the right thyroid lobe. A 39-year-old woman had an enlarging nodule of the right thyroid lobe. Results of thyroid function tests suggested subclinical hyperthyroidism. Two months later, the patient complained of increasing swelling in the neck (but still had no symptoms suggestive of hyperthyroidism). Thus, resection of the right thyroid lobe was performed. Pathologic analysis disclosed low-grade papillary thyroid carcinoma within the nodule, with a small rim of compressed inactive-appearing thyroid tissue surrounding the nodule. Subsequently, she underwent total thyroidectomy and follow-up care for thyroid carcinoma. Although solitary hyperfunctioning nodules of the thyroid gland are usually considered benign, the current case suggests that the diagnosis of autonomous thyroid nodules does not preclude thyroid carcinoma in a functioning nodule.

Assessment of the value of quantitative thyroid scintigraphy for determination of thyroid function in dogs.

PubMed

Shiel, R E; Pinilla, M; McAllister, H; Mooney, C T

2012-05-01

To assess the value of thyroid scintigraphy to determine thyroid status in dogs with hypothyroidism and various non-thyroidal illnesses. Thyroid hormone concentrations were measured and quantitative thyroid scintigraphy performed in 21 dogs with clinical and/or clinicopathological features consistent with hypothyroidism. In 14 dogs with technetium thyroidal uptake values consistent with euthyroidism, further investigations supported non-thyroidal illness. In five dogs with technetium thyroidal uptake values within the hypothyroid range, primary hypothyroidism was confirmed as the only disease in four. The remaining dog had pituitary-dependent hyperadrenocorticism. Two dogs had technetium thyroidal uptake values in the non-diagnostic range. One dog had iodothyronine concentrations indicative of euthyroidism. In the other, a dog receiving glucocorticoid therapy, all iodothyronine concentrations were decreased. Markedly asymmetric technetium thyroidal uptake was present in two dogs. All iodothyronine concentrations were within reference interval but canine thyroid stimulating hormone concentration was elevated in one. Non-thyroidal illness was identified in both cases. In dogs, technetium thyroidal uptake is a useful test to determine thyroid function. However, values may be non-diagnostic, asymmetric uptake can occur and excess glucocorticoids may variably suppress technetium thyroidal uptake and/or thyroid hormone concentrations. Further studies are necessary to evaluate quantitative thyroid scintigraphy as a gold standard method for determining canine thyroid function. © 2012 British Small Animal Veterinary Association.

Thyroid status and nitric oxide in rat arterial vessels.

PubMed

McAllister, R M; Albarracin, I; Price, E M; Smith, T K; Turk, J R; Wyatt, K D

2005-04-01

Thyroid disease has profound effects on cardiovascular function. Hypo- and hyperthyroidism, for example, are associated with reduced and increased maximal endothelium-dependent vasodilation respectively. We therefore hypothesized that the capacity for vascular nitric oxide (NO) formation is decreased in hypothyroidism and increased in hyperthyroidism. To test this hypothesis, rats were made hypothyroid (HYPO) with propylthiouracil or hyperthyroid (HYPER) with triiodothyronine over 3-4 months. Compared with euthyroid control rats (EUT), HYPO exhibited blunted growth and lower citrate synthase activity in the soleus muscle; HYPER exhibited left ventricular hypertrophy and higher citrate synthase activity in the soleus muscle (P<0.05 for all effects). The capacity for NO formation was determined in aortic extracts by formation of [3H]L-citrulline from [3H]L-arginine, i.e. NO synthase (NOS) activity. Thyroid status modulated NOS activity (EUT, 36.8 +/- 5.5 fmol/h per mg protein; HYPO, 26.0 +/- 7.9; HYPER, 64.6 +/- 12.7; P<0.05, HYPER vs HYPO). Expression of endothelial and neural isoforms of NOS was modulated by thyroid status in a parallel fashion. Capacity for responding to NO was also determined via measuring cGMP concentration in aortae incubated with sodium nitroprusside. Stimulated cGMP formation was also modulated by thyroid status (EUT, 73.0 +/- 20.2 pmol/mg protein; HYPO, 152.4 +/- 48.7; HYPER, 10.4 +/- 2.6; P<0.05, HYPER vs HYPO). These data indicate that thyroid status alters capacities for both formation of and responding to NO. The former finding may contribute to previous findings concerning vascular function in thyroid disease states.

Relational Stability in the Expression of Normality, Variation, and Control of Thyroid Function

PubMed Central

Hoermann, Rudolf; Midgley, John E. M.; Larisch, Rolf; Dietrich, Johannes W.

2016-01-01

Thyroid hormone concentrations only become sufficient to maintain a euthyroid state through appropriate stimulation by pituitary thyroid-stimulating hormone (TSH). In such a dynamic system under constant high pressure, guarding against overstimulation becomes vital. Therefore, several defensive mechanisms protect against accidental overstimulation, such as plasma protein binding, conversion of T4 into the more active T3, active transmembrane transport, counter-regulatory activities of reverse T3 and thyronamines, and negative hypothalamic–pituitary–thyroid feedback control of TSH. TSH has gained a dominant but misguided role in interpreting thyroid function testing in assuming that its exceptional sensitivity thereby translates into superior diagnostic performance. However, TSH-dependent thyroid disease classification is heavily influenced by statistical analytic techniques such as uni- or multivariate-defined normality. This demands a separation of its conjoint roles as a sensitive screening test and accurate diagnostic tool. Homeostatic equilibria (set points) in healthy subjects are less variable and do not follow a pattern of random variation, rather indicating signs of early and progressive homeostatic control across the euthyroid range. In the event of imminent thyroid failure with a reduced FT4 output per unit TSH, conversion efficiency increases in order to maintain FT3 stability. In such situations, T3 stability takes priority over set point maintenance. This suggests a concept of relational stability. These findings have important implications for both TSH reference limits and treatment targets for patients on levothyroxine. The use of archival markers is proposed to facilitate the homeostatic interpretation of all parameters. PMID:27872610

The WOMED model of benign thyroid disease: Acquired magnesium deficiency due to physical and psychological stressors relates to dysfunction of oxidative phosphorylation

PubMed Central

Moncayo, Roy; Moncayo, Helga

2014-01-01

Background The aim of this study was to discern whether a relation between biochemical parameters, sonography and musculoskeletal data exists in cases of hyperthyroidism and whether they are modifiable through supplementation with selenomethionine and magnesium citrate as well as by acupuncture and manual medicine methods. Results A direct correlation between whole blood selenium and serum magnesium was found in subjects without thyroid disease and in menopausal women while it was reversed in cases of thyroid diseases as well as in patients with depression, infection, and in infertile women. Vascularization indices were elevated in cases of newly diagnosed benign thyroid diseases. Musculoskeletal changes i.e. lateral tension and idiopathic moving toes, as well as situations of physical and psychological stress and minor trauma and infection led to an increase of vascularization. Magnesium levels correlated negatively with these two conditions. The supplementation brought a reduction of the vascularization indices and reduced the incidence of idiopathic moving toes. Treatment of lateral tension required manual medicine methods and acupuncture (gastrocnemius). A small subgroup of patients showed a further reduction of hyper-vascularization after receiving coenzyme Q10. Conclusions We interpret the elevated thyroid vascularization and low magnesium levels as signs of an inflammatory process related to the musculoskeletal changes. Improvement of thyroid function and morphology can be achieved after correcting the influence of stressors together with the supplementation regime. We hypothesize that the central biochemical event in thyroid disease is that of an acquired, altered mitochondrial function due to deficiency of magnesium, selenium, and coenzyme Q10. PMID:26675817

The pharmacists' role in improving guideline compliance for thyroid function testing in patients with heart failure.

PubMed

Ziman, Melanie E; Bui, Hien T; Smith, Craig S; Tsukiji, Lori A; Asmatey, Veda M; Chu, Steven B; Miano, John S

2012-04-01

This single-center retrospective pilot program's objective was to utilize outpatient pharmacists to improve laboratory test adherence in chronic heart failure (CHF) patients overdue for thyroid function testing, thereby demonstrating the value of the outpatient pharmacist and justifying possible clinical role expansion. Thyroid disorders may contribute to CHF development, progression, and exacerbation. Testing is the standard of care in CHF patients per American Heart Association's 2009 Guidelines. Delinquency was defined as labs not conducted within 1 year in patients with euthyroid history, within 6 months in patients with thyroid dysfunction, abnormal labs at any time without follow-up, or lab absence after thyroid medication initiation, adjustment, or discontinuation. Targeted 80 nonpregnant adult CHF patients with delinquent thyroid function tests were counseled to get thyroid labs at point of sale, via telephone, e-mail, or letter. In collaboration with physicians, pharmacists ordered thyroid-stimulating hormone (TSH) and free T4 (FT4) labs. For patients with abnormal laboratory results, pharmacists coordinated drug therapy and follow-up labs. Data were collected from November 1, 2009 to March 30, 2010. Seventy-two patients (90%) previously delinquent for thyroid function testing received relevant thyroid labs. Ten patients (12.5%) with abnormal thyroid function tests not on prior drug therapy received treatment.

Thyroid and parathyroid imaging

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sandler, M.P.; Patton, J.A.; Partain, C.L.

1986-01-01

This book describes the numerous modalities currently used in the diagnosis and treatment of both thyroid and parathyroid disorders. Each modality is fully explained and then evaluated in terms of benefits and limitations in the clinical context. Contents: Production and Quality Control of Radiopharmaceutics Used for Diagnosis and Therapy in Thyroid and Parathyroid Disorders. Basic Physics. Nuclear Instrumentation. Radioimmunoassay: Thyroid Function Tests. Quality Control. Embryology, Anatomy, Physiology, and Thyroid Function Studies. Scintigraphic Thyroid Imaging. Neonatal and Pediatric Thyroid Imaging. Radioiodine Thyroid Uptake Measurement. Radioiodine Treatment of Thyroid Disorders. Radiation Dosimetry of Diagnostic Procedures. Radiation Safety Procedures for High-Level I-131 Therapies.more » X-Ray Fluorescent Scanning. Thyroid Sonography. Computed Tomography in Thyroid Disease. Magnetic Resonance Imaging in Thyroid Disease. Parathyroid Imaging.« less

The Evolution of Thyroid Function after Presenting with Hashimoto Thyroiditis Is Different between Initially Euthyroid Girls with and Those without Turner Syndrome.

PubMed

Wasniewska, Malgorzata; Salerno, Mariacarolina; Corrias, Andrea; Mazzanti, Laura; Matarazzo, Patrizia; Corica, Domenico; Aversa, Tommaso; Messina, Maria Francesca; De Luca, Filippo; Valenzise, Mariella

2016-01-01

To prospectively investigate, during a 5-year follow-up, whether the prognosis of thyroid function with Hashimoto thyroiditis (HT) is different in euthyroid girls with Turner syndrome (TS) than in euthyroid girls without TS. In 66 TS girls and 132 non-TS girls with euthyroid HT and similar thyroid functional test results at HT diagnosis, we followed up the evolution of thyroid status over time. At the end of follow-up, the TS girls exhibited higher TSH levels, lower fT4 levels, and lower prevalence rates of both euthyroidism and subclinical hypothyroidism, but higher prevalence rates of both overt hypothyroidism and hyperthyroidism, irrespective of the karyotype. An association with TS is able to impair the long-term prognosis of thyroid function in girls with HT. Such an effect occurs irrespective of thyroid functional test results at HT diagnosis and is not necessarily linked with a specific karyotype. © 2016 S. Karger AG, Basel.

Administration of 3,5-diiodothyronine (3,5-T2) causes central hypothyroidism and stimulates thyroid-sensitive tissues.

PubMed

Padron, Alvaro Souto; Neto, Ruy Andrade Louzada; Pantaleão, Thiago Urgal; de Souza dos Santos, Maria Carolina; Araujo, Renata Lopes; de Andrade, Bruno Moulin; da Silva Leandro, Monique; de Castro, João Pedro Saar Werneck; Ferreira, Andrea Claudia Freitas; de Carvalho, Denise Pires

2014-06-01

In general, 3,5-diiodothyronine (3,5-T2) increases the resting metabolic rate and oxygen consumption, exerting short-term beneficial metabolic effects on rats subjected to a high-fat diet. Our aim was to evaluate the effects of chronic 3,5-T2 administration on the hypothalamus-pituitary-thyroid axis, body mass gain, adipose tissue mass, and body oxygen consumption in Wistar rats from 3 to 6 months of age. The rats were treated daily with 3,5-T2 (25, 50, or 75 μg/100 g body weight, s.c.) for 90 days between the ages of 3 and 6 months. The administration of 3,5-T2 suppressed thyroid function, reducing not only thyroid iodide uptake but also thyroperoxidase, NADPH oxidase 4 (NOX4), and thyroid type 1 iodothyronine deiodinase (D1 (DIO1)) activities and expression levels, whereas the expression of the TSH receptor and dual oxidase (DUOX) were increased. Serum TSH, 3,3',5-triiodothyronine, and thyroxine were reduced in a 3,5-T2 dose-dependent manner, whereas oxygen consumption increased in these animals, indicating the direct action of 3,5-T2 on this physiological variable. Type 2 deiodinase activity increased in both the hypothalamus and the pituitary, and D1 activities in the liver and kidney were also increased in groups treated with 3,5-T2. Moreover, after 3 months of 3,5-T2 administration, body mass and retroperitoneal fat pad mass were significantly reduced, whereas the heart rate and mass were unchanged. Thus, 3,5-T2 acts as a direct stimulator of energy expenditure and reduces body mass gain; however, TSH suppression may develop secondary to 3,5-T2 administration. © 2014 The authors.

Thyroid function and obesity.

PubMed

Laurberg, Peter; Knudsen, Nils; Andersen, Stig; Carlé, Allan; Pedersen, Inge Bülow; Karmisholt, Jesper

2012-10-01

Important interaction exists between thyroid function, weight control, and obesity. Several mechanisms seem to be involved, and in studies of groups of people the pattern of thyroid function tests depends on the balance of obesity and underlying thyroid disease in the cohort studied. Obese people with a normal thyroid gland tend to have activation of the hypothalamic-pituitary-thyroid axis with higher serum TSH and thyroid hormones in serum. On the other hand, small differences in thyroid function are associated with up to 5 kg difference in body weight. The weight loss after therapy of overt hypothyroidism is caused by excretion of water bound in tissues (myxoedema). Many patients treated for hyperthyroidism experience a gain of more weight than they lost during the active phase of the disease. The mechanism for this excessive weight gain has not been fully elucidated. New studies on the relation between L-T3 therapy and weight control are discussed. The interaction between weight control and therapy of thyroid disease is important to many patients and it should be studied in more detail.

The renin-angiotensin system in thyroid disorders and its role in cardiovascular and renal manifestations.

PubMed

Vargas, Félix; Rodríguez-Gómez, Isabel; Vargas-Tendero, Pablo; Jimenez, Eugenio; Montiel, Mercedes

2012-04-01

Thyroid disorders are among the most common endocrine diseases and affect virtually all physiological systems, with an especially marked impact on cardiovascular and renal systems. This review summarizes the effects of thyroid hormones on the renin-angiotensin system (RAS) and the participation of the RAS in the cardiovascular and renal manifestations of thyroid disorders. Thyroid hormones are important regulators of cardiac and renal mass, vascular function, renal sodium handling, and consequently blood pressure (BP). The RAS acts globally to control cardiovascular and renal functions, while RAS components act systemically and locally in individual organs. Various authors have implicated the systemic and local RAS in the mediation of functional and structural changes in cardiovascular and renal tissues due to abnormal thyroid hormone levels. This review analyzes the influence of thyroid hormones on RAS components and discusses the role of the RAS in BP, cardiac mass, vascular function, and renal abnormalities in thyroid disorders.

Activated Leukocyte Cell Adhesion Molecule Expression and Shedding in Thyroid Tumors

PubMed Central

Miccichè, Francesca; Da Riva, Luca; Fabbi, Marina; Pilotti, Silvana; Mondellini, Piera; Ferrini, Silvano; Canevari, Silvana; Pierotti, Marco A.; Bongarzone, Italia

2011-01-01

Activated leukocyte cell adhesion molecule (ALCAM, CD166) is expressed in various tissues, cancers, and cancer-initiating cells. Alterations in expression of ALCAM have been reported in several human tumors, and cell adhesion functions have been proposed to explain its association with cancer. Here we documented high levels of ALCAM expression in human thyroid tumors and cell lines. Through proteomic characterization of ALCAM expression in the human papillary thyroid carcinoma cell line TPC-1, we identified the presence of a full-length membrane-associated isoform in cell lysate and of soluble ALCAM isoforms in conditioned medium. This finding is consistent with proteolytically shed ALCAM ectodomains. Nonspecific agents, such as phorbol myristate acetate (PMA) or ionomycin, provoked increased ectodomain shedding. Epidermal growth factor receptor stimulation also enhanced ALCAM secretion through an ADAM17/TACE-dependent pathway. ADAM17/TACE was expressed in the TPC-1 cell line, and ADAM17/TACE silencing by specific small interfering RNAs reduced ALCAM shedding. In addition, the CGS27023A inhibitor of ADAM17/TACE function reduced ALCAM release in a dose-dependent manner and inhibited cell migration in a wound-healing assay. We also provide evidence for the existence of novel O-glycosylated forms and of a novel 60-kDa soluble form of ALCAM, which is particularly abundant following cell stimulation by PMA. ALCAM expression in papillary and medullary thyroid cancer specimens and in the surrounding non-tumoral component was studied by western blot and immunohistochemistry, with results demonstrating that tumor cells overexpress ALCAM. These findings strongly suggest the possibility that ALCAM may have an important role in thyroid tumor biology. PMID:21364949

MicroRNAs in thyroid development, function and tumorigenesis.

PubMed

Fuziwara, Cesar Seigi; Kimura, Edna Teruko

2017-11-15

MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression that modulate the vast majority of cellular processes. During development, the correct timing and expression of miRNAs in the tissue differentiation is essential for organogenesis and functionality. In thyroid gland, DICER and miRNAs are necessary for accurately establishing thyroid follicles and hormone synthesis. Moreover, DICER1 mutations and miRNA deregulation observed in human goiter influence thyroid tumorigenesis. The thyroid malignant transformation by MAPK oncogenes is accompanied by global miRNA changes, with a marked reduction of "tumor-suppressor" miRNAs and activation of oncogenic miRNAs. Loss of thyroid cell differentiation/function, and consequently iodine trapping impairment, is an important clinical characteristic of radioiodine-refractory thyroid cancer. However, few studies have addressed the direct role of miRNAs in thyroid gland physiology. Here, we focus on what we have learned in the thyroid follicular cell differentiation and function as revealed by cell and animal models and miRNA modulation in thyroid tumorigenesis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

An animal model of marginal iodine deficiency during development: the thyroid axis and neurodevelopmental outcome.

PubMed

Gilbert, Mary E; Hedge, Joan M; Valentín-Blasini, Liza; Blount, Benjamin C; Kannan, Kurunthachalam; Tietge, Joseph; Zoeller, R Thomas; Crofton, Kevin M; Jarrett, Jeffrey M; Fisher, Jeffrey W

2013-03-01

Thyroid hormones (THs) are essential for brain development, and iodine is required for TH synthesis. Environmental chemicals that perturb the thyroid axis result in modest reductions in TH, yet there is a paucity of data on the extent of neurological impairments associated with low-level TH disruption. This study examined the dose-response characteristics of marginal iodine deficiency (ID) on parameters of thyroid function and neurodevelopment. Diets deficient in iodine were prepared by adding 975, 200, 125, 25, or 0 µg/kg potassium iodate to the base casein diet to produce five nominal iodine levels ranging from ample (Diet 1: 1000 μg iodine/kg chow, D1) to deficient (Diet 5: 25 µg iodine/kg chow, D5). Female Long Evans rats were maintained on these diets beginning 7 weeks prior to breeding until the end of lactation. Dams were sacrificed on gestational days 16 and 20, or when pups were weaned on postnatal day (PN) 21. Fetal tissue was harvested from the dams, and pups were sacrificed on PN14 and PN21. Blood, thyroid gland, and brain were collected for analysis of iodine, TH, and TH precursors and metabolites. Serum and thyroid gland iodine and TH were reduced in animals receiving two diets that were most deficient in iodine. T4 was reduced in the fetal brain but was not altered in the neonatal brain. Neurobehavior, assessed by acoustic startle, water maze learning, and fear conditioning, was unchanged in adult offspring, but excitatory synaptic transmission was impaired in the dentate gyrus in animals receiving two diets that were most deficient in iodine. A 15% reduction in cortical T4 in the fetal brain was sufficient to induce permanent reductions in synaptic function in adults. These findings have implications for regulation of TH-disrupting chemicals and suggest that standard behavioral assays do not readily detect neurotoxicity induced by modest developmental TH disruption.

Iodine neutron capture therapy

NASA Astrophysics Data System (ADS)

Ahmed, Kazi Fariduddin

A new technique, Iodine Neutron Capture Therapy (INCT) is proposed to treat hyperthyroidism in people. Present thyroid therapies, surgical removal and 131I treatment, result in hypothyroidism and, for 131I, involve protracted treatment times and excessive whole-body radiation doses. The new technique involves using a low energy neutron beam to convert a fraction of the natural iodine stored in the thyroid to radioactive 128I, which has a 24-minute half-life and decays by emitting 2.12-MeV beta particles. The beta particles are absorbed in and damage some thyroid tissue cells and consequently reduce the production and release of thyroid hormones to the blood stream. Treatment times and whole-body radiation doses are thus reduced substantially. This dissertation addresses the first of the several steps needed to obtain medical profession acceptance and regulatory approval to implement this therapy. As with other such programs, initial feasibility is established by performing experiments on suitable small mammals. Laboratory rats were used and their thyroids were exposed to the beta particles coming from small encapsulated amounts of 128I. Masses of 89.0 mg reagent-grade elemental iodine crystals have been activated in the ISU AGN-201 reactor to provide 0.033 mBq of 128I. This activity delivers 0.2 Gy to the thyroid gland of 300-g male rats having fresh thyroid tissue masses of ˜20 mg. Larger iodine masses are used to provide greater doses. The activated iodine is encapsulated to form a thin (0.16 cm 2/mg) patch that is then applied directly to the surgically exposed thyroid of an anesthetized rat. Direct neutron irradiation of a rat's thyroid was not possible due to its small size. Direct in-vivo exposure of the thyroid of the rat to the emitted radiation from 128I is allowed to continue for 2.5 hours (6 half-lives). Pre- and post-exposure blood samples are taken to quantify thyroid hormone levels. The serum T4 concentration is measured by radioimmunoassay at different times after exposure as an indicator of thyroid function. Cell damage is assessed by postmortem histopathologic examination. The intent of this endeavor is to relate radiation dose, T4 concentration in the blood stream and cellular damage. This information will help better understand the dose response relationship of thyroid cells exposed to ionizing radiation.

Management of hyper and hypo thyroid conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Locke, W.

1982-03-01

In hyperthyroidism, the primary objective of therapy is to reduce secretion of thyroid hormone, which can be accomplished in various ways. The stimulus to hypersecretion can be removed in some causes of hyperthyroidism; in others, hormone synthesis and release can be inhibited by drugs such as thioamides, adrenergic blocking agents, or possibly lithium or glucocorticoids. Radioactive iodine is indicated for primary therapy of uncomplicated hyperthyroidism due to Graves' disease in persons over 30 years of age (myxedema may be a complication) and for treatment of autonomous thyroid adenoma in patients who are not suitable candidates for surgery. Surgical ablation ismore » preferred for some causes of hyperthyroidism but may induce postoperative hypothyroidism. Hypothyroidism due to thyroid failure usually presents few therapeutic difficulties and can be managed simply by long-term hormone replacement. Before hormone replacement is prescribed for secondary or tertiary hypothyroidism, the other pituitary functions should be assessed.« less

Culture promotes transfer of thyroid epithelial cell hyperplasia and proliferation by reducing regulatory T cell numbers.

PubMed

Kayes, Timothy D; Braley-Mullen, Helen

2013-01-01

IFN-γ(-/-) NOD.H-2h4 mice develop a spontaneous autoimmune thyroid disease, thyroid epithelial cell hyperplasia and proliferation (TEC H/P) when given NaI in their water for 7+ mo. TEC H/P can be transferred to IFN-γ(-/-) SCID mice by splenocytes from mice with severe (4-5+) disease, and transfer of TEC H/P is improved when splenocytes are cultured prior to transfer. Older (9+ mo) IFN-γ(-/-) NOD.H-2h4 mice have elevated numbers of FoxP3(+) T reg cells, up to 2-fold greater than younger (2 mo) mice. During culture, the number of T reg decreases and this allows the improved transfer of TEC H/P. Co-culture with IL-2 prior to transfer prevents the decrease of T reg and improves their in vitro suppressive ability resulting in reduced TEC H/P in recipient mice. Therefore, culturing splenocytes improves transfer of TEC H/P by reducing the number of T reg and IL-2 inhibits transfer by preserving T reg number and function. Copyright © 2013 Elsevier Inc. All rights reserved.

Moderate perinatal thyroid hormone insufficiency alters visual system function in adult rats.

PubMed

Boyes, William K; Degn, Laura; George, Barbara Jane; Gilbert, Mary E

2018-04-21

Thyroid hormone (TH) is critical for many aspects of neurodevelopment and can be disrupted by a variety of environmental contaminants. Sensory systems, including audition and vision are vulnerable to TH insufficiencies, but little data are available on visual system development at less than severe levels of TH deprivation. The goal of the current experiments was to explore dose-response relations between graded levels of TH insufficiency during development and the visual function of adult offspring. Pregnant Long Evans rats received 0 or 3 ppm (Experiment 1), or 0, 1, 2, or 3 ppm (Experiment 2) of propylthiouracil (PTU), an inhibitor of thyroid hormone synthesis, in drinking water from gestation day (GD) 6 to postnatal day (PN) 21. Treatment with PTU caused dose-related reductions of serum T4, with recovery on termination of exposure, and euthyroidism by the time of visual function testing. Tests of retinal (electroretinograms; ERGs) and visual cortex (visual evoked potentials; VEPs) function were assessed in adult offspring. Dark-adapted ERG a-waves, reflecting rod photoreceptors, were increased in amplitude by PTU. Light-adapted green flicker ERGs, reflecting M-cone photoreceptors, were reduced by PTU exposure. UV-flicker ERGs, reflecting S-cones, were not altered. Pattern-elicited VEPs were significantly reduced by 2 and 3 ppm PTU across a range of stimulus contrast values. The slope of VEP amplitude-log contrast functions was reduced by PTU, suggesting impaired visual contrast gain. Visual contrast gain primarily reflects function of visual cortex, and is responsible for adjusting sensitivity of perceptual mechanisms in response to changing visual scenes. The results indicate that moderate levels of pre-and post-natal TH insufficiency led to alterations in visual function of adult rats, including both retinal and visual cortex sites of dysfunction. Copyright © 2018. Published by Elsevier B.V.

Low-level laser in the treatment of patients with hypothyroidism induced by chronic autoimmune thyroiditis: a randomized, placebo-controlled clinical trial.

PubMed

Höfling, Danilo B; Chavantes, Maria Cristina; Juliano, Adriana G; Cerri, Giovanni G; Knobel, Meyer; Yoshimura, Elisabeth M; Chammas, Maria Cristina

2013-05-01

Chronic autoimmune thyroiditis (CAT) is the most common cause of acquired hypothyroidism, which requires lifelong levothyroxine replacement therapy. Currently, no effective therapy is available for CAT. Thus, the objective of this study was to evaluate the efficacy of low-level laser therapy (LLLT) in patients with CAT-induced hypothyroidism by testing thyroid function, thyroid peroxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb), and ultrasonographic echogenicity. A randomized, placebo-controlled trial with a 9-month follow-up was conducted from 2006 to 2009. Forty-three patients with a history of levothyroxine therapy for CAT-induced hypothyroidism were randomly assigned to receive either 10 sessions of LLLT (830 nm, output power of 50 mW, and fluence of 707 J/cm(2); L group, n=23) or 10 sessions of a placebo treatment (P group, n=20). The levothyroxine was suspended 30 days after the LLLT or placebo procedures. Thyroid function was estimated by the levothyroxine dose required to achieve normal concentrations of T3, T4, free-T4 (fT4), and thyrotropin after 9 months of postlevothyroxine withdrawal. Autoimmunity was assessed by measuring the TPOAb and TgAb levels. A quantitative computerized echogenicity analysis was performed pre- and 30 days postintervention. The results showed a significant difference in the mean levothyroxine dose required to treat the hypothyroidism between the L group (38.59 ± 20.22 μg/day) and the P group (106.88 ± 22.90 μg/day, P<0.001). Lower TPOAb (P=0.043) and greater echogenicity (P<0.001) were also noted in the L group. No TgAb difference was observed. These findings suggest that LLLT was effective at improving thyroid function, promoting reduced TPOAb-mediated autoimmunity and increasing thyroid echogenicity in patients with CAT hypothyroidism.

The Risk of Preeclampsia According to High Thyroid Function in Pregnancy Differs by hCG Concentration.

PubMed

Korevaar, Tim I M; Steegers, Eric A P; Chaker, Layal; Medici, Marco; Jaddoe, Vincent W V; Visser, Theo J; de Rijke, Yolanda B; Peeters, Robin P

2016-12-01

During pregnancy, there is an increased demand for thyroid hormone. The pregnancy hormone human chorionic gonadotropin (hCG) is an important physiological stimulator of thyroid function. Already high-normal maternal free T 4 concentrations are associated with a higher risk of preeclampsia. The objective of the investigation was to study our hypothesis that hCG concentrations can distinguish a physiological form of high thyroid function from a more pathological form of high thyroid function and that the risk of preeclampsia would differ accordingly. TSH, free T 4 , hCG, or thyroperoxidase antibody concentrations were determined in pregnant women participating in a population-based prospective cohort study. The study was conducted in the general community. A nonselected sample of 5146 pregnant women participated in the study. There were no interventions. Preeclampsia was measured. Women with high hCG-associated high thyroid function did not have a higher risk of preeclampsia than women with normal thyroid function. In contrast, women with low hCG and high thyroid function had a 3.4- to 11.1-fold higher risk of preeclampsia. These risk estimates were amplified in women with a high body mass index. Women with a low hCG and suppressed TSH (<0.10 mU/L) had a 3.2- to 8.9-fold higher risk of preeclampsia. hCG was not associated with preeclampsia, and results remained similar after exclusion of thyroperoxidase antibody-positive women. This study suggests that, in contrast to women with a high hCG associated high thyroid function, women with low hCG and high thyroid function during pregnancy are at a higher risk of developing preeclampsia. The additional measurement of hCG may therefore help to distinguish a more pathological form of high thyroid function and women at a high risk of preeclampsia.

Combined Effects of Perchlorate, Thiocyanate, and Iodine on Thyroid Function in the National Health and Nutrition Examination Survey 2007-8

PubMed Central

Steinmaus, Craig; Miller, Mark D.; Cushing, Lara; Blount, Benjamin C.; Smith, Allan H.

2013-01-01

Perchlorate, thiocyanate, and low iodine intake can all decrease iodide intake into the thyroid gland. This can reduce thyroid hormone production since iodide is a key component of thyroid hormone. Previous research has suggested that each of these factors alone may decrease thyroid hormone levels, but effect sizes are small. We hypothesized that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time. Using data from the 2007-2008 National Health and Nutrition Examination Survey, subjects were categorized into exposure groups based on their urinary perchlorate, iodine, and thiocyanate concentrations, and mean serum thyroxine concentrations were compared between groups. Subjects with high perchlorate (n=1939) had thyroxine concentrations that were 5.0% lower (mean difference = 0.40 µg/dl, 95% confidence interval=0.14-0.65) than subjects with low perchlorate (n=2084). The individual effects of iodine and thiocyanate were even smaller. Subjects with high perchlorate, high thiocyanate, and low iodine combined (n=62) had thyroxine concentrations 12.9% lower (mean difference = 1.07 µg/dl, 95% confidence interval=0.55-1.59) than subjects with low perchlorate, low thiocyanate, and adequate iodine (n=376). Potential confounders had little impact on results. Overall, these results suggest that concomitant exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production. This highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents. PMID:23473920

Thyroid peroxidase (TPO) expressed in thyroid and breast tissues shows similar antigenic properties.

PubMed

Godlewska, Marlena; Arczewska, Katarzyna D; Rudzińska, Magdalena; Łyczkowska, Anna; Krasuska, Wanda; Hanusek, Karolina; Ruf, Jean; Kiedrowski, Mirosław; Czarnocka, Barbara

2017-01-01

Thyroid peroxidase (TPO) is essential for physiological function of the thyroid gland. The high prevalence of thyroid peroxidase antibodies (TPOAbs) in patients with breast cancer and their protective role had previously been demonstrated, indicating a link between breast cancer and thyroid autoimmunity. Recently, TPO was shown to be present in breast cancer tissue samples but its antigenicity has not been analyzed. In this study, we investigated TPO expression levels in a series of fifty-six breast cancer samples paired with normal (peri-tumoral) tissue and its antigenic activity using a panel of well-characterized murine anti-human TPOAbs. We have shown that TPO transcripts were present in both normal and cancer tissue samples, although the amounts in the latter were reduced. Additionally, we observed that TPO levels are lower in more advanced cancers. TPO protein expression was confirmed in all tissue samples, both normal and cancerous. We also found that the antigenicity of the immunodominant regions (IDRs) in breast TPO resembles that of thyroid TPO, which is crucial for effective interactions with human TPOAbs. Expression of TPO in breast cancer together with its antigenic activity may have beneficial effects in TPOAb-positive breast cancer patients. However, further studies are needed to confirm the beneficial role of TPOAbs and to better understand the underlying mechanism.

Thyroid function and the risk of dementia: The Rotterdam Study.

PubMed

Chaker, Layal; Wolters, Frank J; Bos, Daniel; Korevaar, Tim I M; Hofman, Albert; van der Lugt, Aad; Koudstaal, Peter J; Franco, Oscar H; Dehghan, Abbas; Vernooij, Meike W; Peeters, Robin P; Ikram, M Arfan

2016-10-18

To study the role of thyroid function in dementia, cognitive function, and subclinical vascular brain disease with MRI. Analyses were performed within the Rotterdam Study (baseline 1997), a prospective, population-based cohort. We evaluated the association of thyroid-stimulating hormone (TSH) and free thyroxine with incident dementia using Cox models adjusted for age, sex, cardiovascular risk factors, and education. Absolute risks were calculated accounting for death as a competing risk factor. Associations of thyroid function with cognitive test scores and subclinical vascular brain disease (white matter lesions, lacunes, and microbleeds) were assessed with linear or logistic regression. Additionally, we stratified by sex and restricted analyses to normal thyroid function. We included 9,446 participants with a mean age of 65 years. During follow-up (mean 8.0 years), 601 participants had developed dementia. Higher TSH was associated with lower dementia risk in both the full and normal ranges of thyroid function (hazard ratio [HR] 0.90, 95% confidence interval [CI] 0.83-0.98; and HR 0.76, 95% CI 0.64-0.91, respectively). This association was independent of cardiovascular risk factors. Dementia risk was higher in individuals with higher free thyroxine (HR 1.04, 95% CI 1.01-1.07). Absolute 10-year dementia risk decreased from 15% to 10% with higher TSH in older women. Higher TSH was associated with better global cognitive scores (p = 0.021). Thyroid function was not related to subclinical vascular brain disease as indicated by MRI. High and high-normal thyroid function is associated with increased dementia risk. Thyroid function is not related to vascular brain disease as assessed by MRI, suggesting a role for thyroid hormone in nonvascular pathways leading to dementia. © 2016 American Academy of Neurology.

Assessment of renal function and electrolytes in patients with thyroid dysfunction in Addis Ababa, Ethiopia: a cross sectional study.

PubMed

Abebe, Nardos; Kebede, Tedla; Wolde, Mistire

2016-01-01

Studies demonstrated that abnormal thyroid functions may result in decreased or increased kidney size, kidney weight, and affect renal functions. In this regard, studies on the association of abnormal thyroid functions and renal function tests are scarcely found in Ethiopia. To assess renal function and electrolytes in patients with thyroid dysfunction, in Addis Ababa, Ethiopia. Cross sectional study was conducted from March 21/2015-May 27/2015 at Arsho Advanced Medical Laboratory. During the study period, 71 patients with thyroid dysfunction were eligible, and socio demographic data collected by structured questionnaire. Then blood sample was collected for thyroid function tests, renal function and blood electrolyte analysis. The collected data was analyzed by SPSS version 20. ANOVA and binary logistic regression were employed to evaluate the mean deference and associations of thyroid hormone with renal function and electrolyte balances. Among the renal function tests, serum uric acid, and creatinine mean values were significantly decreased in hyperthyroid patients; whereas, eGFR mean value was significantly increased in hyperthyroid study patients (P<0.05). Meanwhile, from the electrolyte measurements made, only the mean serum sodium value was significantly increased in hyperthyroid study participants. Binary logistic regression analysis on the association of thyroid dysfunction with electrolyte balance and renal function tests indicated that serum sodium, creatinine, eGFR values and hyperthyroidism have a statistical significant association at AOR 95% CI of 0.141(0.033-0.593, P=0.008); 16.236(3.481-75.739, P=0.001), and 13.797(3.261-58.67, P=0.001) respectively. The current study reveals, thyroid abnormalities may lead to renal function alterations and also may disturb electrolyte balance. Knowledge of this significant association has worthwhile value for clinicians, to manage their patients' optimally.

Effect of zinc supplementation on the status of thyroid hormones and Na, K, And Ca levels in blood following ethanol feeding.

PubMed

Pathak, R; Dhawan, D; Pathak, A

2011-05-01

The influence of zinc (Zn) on the serum levels of triiodothyronine (T(3)), thyroxine (T(4)), thyroid-stimulating hormone (TSH) and sodium (Na), potassium (K), and calcium (Ca) was evaluated following ethanol toxicity to the rats. To achieve this, male Wistar rats (150-195 g) were given 3 ml of 30% ethanol orally, and zinc was given in the form of zinc sulfate (227 mg/l) in their drinking water daily for 8 weeks. Ethanol feeding resulted in a slight decrease in T(3) and T(4) levels and a significant increase in thyroid-stimulating hormone concentration, which may be due to the direct stimulatory effect of ethanol on thyroid. Interestingly, when zinc was given to these rats, all the above levels were brought quite close to their normal levels, thus indicating the positive role of zinc in thyroid hormone metabolism. Serum Zn and Ca levels were found to be reduced, but Na levels were raised upon ethanol feeding. Restoration of normal levels of these metals upon zinc supplementation to ethanol fed rats confirms that zinc has potential in alleviating some of the altered thyroid functions following ethanol administration.

Thyroid hormone increases fibroblast growth factor receptor expression and disrupts cell mechanics in the developing organ of corti

PubMed Central

2013-01-01

Background Thyroid hormones regulate growth and development. However, the molecular mechanisms by which thyroid hormone regulates cell structural development are not fully understood. The mammalian cochlea is an intriguing system to examine these mechanisms, as cellular structure plays a key role in tissue development, and thyroid hormone is required for the maturation of the cochlea in the first postnatal week. Results In hypothyroid conditions, we found disruptions in sensory outer hair cell morphology and fewer microtubules in non-sensory supporting pillar cells. To test the functional consequences of these cytoskeletal defects on cell mechanics, we combined atomic force microscopy with live cell imaging. Hypothyroidism stiffened outer hair cells and supporting pillar cells, but pillar cells ultimately showed reduced cell stiffness, in part from a lack of microtubules. Analyses of changes in transcription and protein phosphorylation suggest that hypothyroidism prolonged expression of fibroblast growth factor receptors, and decreased phosphorylated Cofilin. Conclusions These findings demonstrate that thyroid hormones may be involved in coordinating the processes that regulate cytoskeletal dynamics and suggest that manipulating thyroid hormone sensitivity might provide insight into the relationship between cytoskeletal formation and developing cell mechanical properties. PMID:23394545

Application of a cervical low incision in the functional neck dissection of thyroid papillary carcinoma.

PubMed

Xu, Jiajie; Chen, Chao; Zheng, Chuanming; Wang, Kejing; Shang, Jinbiao; Fang, Xianhua; Ge, Minghua; Tan, Zhuo

2016-04-01

The present study aimed to discuss the advantage of the application of a cervical low incision for functional neck dissection in patients with thyroid papillary carcinoma. The study was a retrospective analysis of 87 thyroid papillary carcinoma patients; cervical low incision in the functional neck dissection was applied for 47 cases and the classic 'L' incision was applied for 40 cases. The different integrity, surgical time, blood loss and the aesthetic property of the incision were compared between the cervical low incision and the classic 'L' incision for lateral neck dissection of thyroid cancer. The postoperative pathological diagnosis was that the average total amount and the region II lymph nodes of the unilateral neck dissection were 33 and 10 for the cervical low incision group, and 32 and 11 for the classic 'L' incision group, respectively (P>0.05). The average unilateral neck dissection times were 87 and 58 min for the cervical low incision group and the classic 'L' incision group, respectively (P<0.05). The blood loss of the cervical low incision group was 67 ml, while the loss for the classic 'L' incision group was 61 ml (P>0.05). The postoperative incision of the cervical low incision group was smaller and more concealing. Additionally, the cosmetic deformities were milder for an inconspicuous cervical scar, and the sensation was improved for the patients in comparison with the classic 'L' incision group. These results suggest that the application of cervical low incision for functional neck dissection in thyroid papillary carcinoma patients aids in reducing postoperative complications, without increasing recurrence rates. Therefore, the classic 'L' incision can be replaced by the cervical low incision.

Application of a cervical low incision in the functional neck dissection of thyroid papillary carcinoma

PubMed Central

XU, JIAJIE; CHEN, CHAO; ZHENG, CHUANMING; WANG, KEJING; SHANG, JINBIAO; FANG, XIANHUA; GE, MINGHUA; TAN, ZHUO

2016-01-01

The present study aimed to discuss the advantage of the application of a cervical low incision for functional neck dissection in patients with thyroid papillary carcinoma. The study was a retrospective analysis of 87 thyroid papillary carcinoma patients; cervical low incision in the functional neck dissection was applied for 47 cases and the classic ‘L’ incision was applied for 40 cases. The different integrity, surgical time, blood loss and the aesthetic property of the incision were compared between the cervical low incision and the classic ‘L’ incision for lateral neck dissection of thyroid cancer. The postoperative pathological diagnosis was that the average total amount and the region II lymph nodes of the unilateral neck dissection were 33 and 10 for the cervical low incision group, and 32 and 11 for the classic ‘L’ incision group, respectively (P>0.05). The average unilateral neck dissection times were 87 and 58 min for the cervical low incision group and the classic ‘L’ incision group, respectively (P<0.05). The blood loss of the cervical low incision group was 67 ml, while the loss for the classic ‘L’ incision group was 61 ml (P>0.05). The postoperative incision of the cervical low incision group was smaller and more concealing. Additionally, the cosmetic deformities were milder for an inconspicuous cervical scar, and the sensation was improved for the patients in comparison with the classic ‘L’ incision group. These results suggest that the application of cervical low incision for functional neck dissection in thyroid papillary carcinoma patients aids in reducing postoperative complications, without increasing recurrence rates. Therefore, the classic ‘L’ incision can be replaced by the cervical low incision. PMID:27073645

THYROID HORMONE REVERSES AGING-INDUCED MYOCARDIAL FATTY ACID OXIDATION DEFECTS AND IMPROVES THE RESPONSE TO ACUTELY INCREASED AFTERLOAD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ledee, Dolena; Portman, Michael A.; Kajimoto, Masaki

Background: Subclinical hypothyroidism occurs during aging in humans and mice and may contribute to development of heart failure. Aging also impairs myocardial fatty acid oxidation, causing increased reliance on flux through pyruvate dehydrogenase (PDH) to maintain function. We hypothesize that the metabolic changes in aged hearts make them less tolerant to acutely increased work and that thyroid hormone reverses these defects. Methods: Studies were performed on young (Young, 4-6 months) and aged (Old, 22-24 months) C57/BL6 mice at standard (50 mmHg) and high afterload (80 mmHg). Another aged group received thyroid hormone for 3 weeks (Old-TH, high afterload only). Functionmore » was measured in isolated working hearts along with substrate fractional contributions (Fc) to the citric acid cycle (CAC) using perfusate with 13C labeled lactate, pyruvate, glucose and unlabeled palmitate and insulin. Results: Cardiac function was similar between Young and Old mice at standard afterload. Palmitate Fc was reduced but no individual carbohydrate contributions differed. CAC and individual substrate fluxes decreased in aged. At high afterload, -dP/dT was decreased in Old versus Young. Similar to low afterload, palmitate Fc was decreased in Old. Thyroid hormone reversed aging-induced changes in palmitate Fc and flux while significantly improving cardiac function. Conclusion: The aged heart shows diminished ability to increase cardiac work due to substrate limitations, primarily impaired fatty acid oxidation. The heart accommodates slightly by increasing efficiency through oxidation of carbohydrate substrates. Thyroid hormone supplementation in aged mice significantly improves cardiac function potentially through restoration of fatty acid oxidation.« less

Thyroiditis

MedlinePlus

... 12-18 months, 20% possibility of permanent hypothyroidism. Post partum thyroiditis Anti-thyroid antibodies, autoimmune disease Thyrotoxicosis followed by hypothyroidism. Thyroid function tests, thyroid antibody tests, radioactive iodine uptake (contraindicated if ...

Weight-of-evidence analysis of human exposures to dioxins and dioxin-like compounds and associations with thyroid hormone levels during early development.

PubMed

Goodman, Julie E; Kerper, Laura E; Boyce, Catherine Petito; Prueitt, Robyn L; Rhomberg, Lorenz R

2010-10-01

Thyroid hormones play a critical role in the proper development of brain function and cell growth. Several epidemiological studies have been conducted to assess potential associations between pre- and post-natal exposure to dioxins or dioxin-like compounds (DLCs) and the levels of circulating thyroid hormones during early development. Dioxins and DLCs include chlorinated dibenzo-p-dioxins, chlorinated dibenzofurans, and mono- and non-ortho polychlorinated biphenyls (PCBs). We identified a total of 23 relevant epidemiological studies (21 cohort studies and 1 case-control study) that measured exposures to various types of dioxins and DLCs as well as markers of thyroid function, such as thyroid stimulating hormone (TSH), total thyroxine (T4), free T4, total triiodothyroxine (T3), free T3, and thyroid-binding globulin concentrations in cord blood or circulation. While some of the studies reported associations between concentrations of dioxins and/or DLCs and some biomarkers of thyroid function, the majority of the observed associations were not statistically significant. Moreover, there were no clear and consistent effects across studies for any of the hormone levels examined, and while a number of studies showed a statistically significant association with exposure for a given marker of thyroid function, other studies showed either no change or changes in the opposite direction for the same thyroid function marker. Similarly, when the results were analyzed considering developmental stage, there generally were no clear and consistent effects at any age from birth through 12 years of age. The absence of a clear correlation between background exposures to dioxins and DLCs and thyroid function biomarkers during development is not consistent with the hypothesis that background exposures to these chemicals cause effects on thyroid function during development. Copyright (c) 2010 Elsevier Inc. All rights reserved.

A meta-analysis of thyroid-related traits reveals novel loci and gender-specific differences in the regulation of thyroid function.

PubMed

Porcu, Eleonora; Medici, Marco; Pistis, Giorgio; Volpato, Claudia B; Wilson, Scott G; Cappola, Anne R; Bos, Steffan D; Deelen, Joris; den Heijer, Martin; Freathy, Rachel M; Lahti, Jari; Liu, Chunyu; Lopez, Lorna M; Nolte, Ilja M; O'Connell, Jeffrey R; Tanaka, Toshiko; Trompet, Stella; Arnold, Alice; Bandinelli, Stefania; Beekman, Marian; Böhringer, Stefan; Brown, Suzanne J; Buckley, Brendan M; Camaschella, Clara; de Craen, Anton J M; Davies, Gail; de Visser, Marieke C H; Ford, Ian; Forsen, Tom; Frayling, Timothy M; Fugazzola, Laura; Gögele, Martin; Hattersley, Andrew T; Hermus, Ad R; Hofman, Albert; Houwing-Duistermaat, Jeanine J; Jensen, Richard A; Kajantie, Eero; Kloppenburg, Margreet; Lim, Ee M; Masciullo, Corrado; Mariotti, Stefano; Minelli, Cosetta; Mitchell, Braxton D; Nagaraja, Ramaiah; Netea-Maier, Romana T; Palotie, Aarno; Persani, Luca; Piras, Maria G; Psaty, Bruce M; Räikkönen, Katri; Richards, J Brent; Rivadeneira, Fernando; Sala, Cinzia; Sabra, Mona M; Sattar, Naveed; Shields, Beverley M; Soranzo, Nicole; Starr, John M; Stott, David J; Sweep, Fred C G J; Usala, Gianluca; van der Klauw, Melanie M; van Heemst, Diana; van Mullem, Alies; Vermeulen, Sita H; Visser, W Edward; Walsh, John P; Westendorp, Rudi G J; Widen, Elisabeth; Zhai, Guangju; Cucca, Francesco; Deary, Ian J; Eriksson, Johan G; Ferrucci, Luigi; Fox, Caroline S; Jukema, J Wouter; Kiemeney, Lambertus A; Pramstaller, Peter P; Schlessinger, David; Shuldiner, Alan R; Slagboom, Eline P; Uitterlinden, André G; Vaidya, Bijay; Visser, Theo J; Wolffenbuttel, Bruce H R; Meulenbelt, Ingrid; Rotter, Jerome I; Spector, Tim D; Hicks, Andrew A; Toniolo, Daniela; Sanna, Serena; Peeters, Robin P; Naitza, Silvia

2013-01-01

Thyroid hormone is essential for normal metabolism and development, and overt abnormalities in thyroid function lead to common endocrine disorders affecting approximately 10% of individuals over their life span. In addition, even mild alterations in thyroid function are associated with weight changes, atrial fibrillation, osteoporosis, and psychiatric disorders. To identify novel variants underlying thyroid function, we performed a large meta-analysis of genome-wide association studies for serum levels of the highly heritable thyroid function markers TSH and FT4, in up to 26,420 and 17,520 euthyroid subjects, respectively. Here we report 26 independent associations, including several novel loci for TSH (PDE10A, VEGFA, IGFBP5, NFIA, SOX9, PRDM11, FGF7, INSR, ABO, MIR1179, NRG1, MBIP, ITPK1, SASH1, GLIS3) and FT4 (LHX3, FOXE1, AADAT, NETO1/FBXO15, LPCAT2/CAPNS2). Notably, only limited overlap was detected between TSH and FT4 associated signals, in spite of the feedback regulation of their circulating levels by the hypothalamic-pituitary-thyroid axis. Five of the reported loci (PDE8B, PDE10A, MAF/LOC440389, NETO1/FBXO15, and LPCAT2/CAPNS2) show strong gender-specific differences, which offer clues for the known sexual dimorphism in thyroid function and related pathologies. Importantly, the TSH-associated loci contribute not only to variation within the normal range, but also to TSH values outside the reference range, suggesting that they may be involved in thyroid dysfunction. Overall, our findings explain, respectively, 5.64% and 2.30% of total TSH and FT4 trait variance, and they improve the current knowledge of the regulation of hypothalamic-pituitary-thyroid axis function and the consequences of genetic variation for hypo- or hyperthyroidism.

Natural History of Thyroid Function in Adults with Down Syndrome--10-Year Follow-Up Study

ERIC Educational Resources Information Center

Prasher, V.; Gomez, G.

2007-01-01

Background: The natural history of thyroid function in adults with Down syndrome (DS) is unknown. Method: This study investigated annual thyroid function tests in 200 adults with DS over a 10-year period. Results: Transient and persistent thyroid dysfunction was common. The 5- and 10-year incidence of definite hypothyroidism was 0.9%-1.64% and…

Intrinsic Regulation of Thyroid Function by Thyroglobulin

PubMed Central

Sellitti, Donald F.

2014-01-01

Background: The established paradigm for thyroglobulin (Tg) function is that of a high molecular weight precursor of the much smaller thyroid hormones, triiodothyronine (T3) and thyroxine (T4). However, speculation regarding the cause of the functional and morphologic heterogeneity of the follicles that make up the thyroid gland has given rise to the proposition that Tg is not only a precursor of thyroid hormones, but that it also functions as an important signal molecule in regulating thyroid hormone biosynthesis. Summary: Evidence supporting this alternative paradigm of Tg function, including the up- or downregulation by colloidal Tg of the transcription of Tg, iodide transporters, and enzymes employed in Tg iodination, and also the effects of Tg on the proliferation of thyroid and nonthyroid cells, is examined in the present review. Also discussed in detail are potential mechanisms of Tg signaling in follicular cells. Conclusions: Finally, we propose a mechanism, based on experimental observations of Tg effects on thyroid cell behavior, that could account for the phenomenon of follicular heterogeneity as a highly regulated cycle of increasing and decreasing colloidal Tg concentration that functions to optimize thyroid hormone production through the transcriptional activation or suppression of specific genes. PMID:24251883

Age impact on autoimmune thyroid disease in females

NASA Astrophysics Data System (ADS)

Stoian, Dana; Craciunescu, Mihalea; Timar, Romulus; Schiller, Adalbert; Pater, Liana; Craina, Marius

2013-10-01

Thyroid autoimmune disease, a widespread phenomenon in female population, impairs thyroid function during pregnancy. Identifying cases, which will develop hypothyroidism during pregnancy, is crucial in the follow-up process. The study group comprised 108 females, with ages between 20-40 years; with known inactive autoimmune thyroid disease, before pregnancy that became pregnant in the study follow-up period. They were monitored by means of clinical, hormonal and immunological assays. Supplemental therapy with thyroid hormones was used, where needed. Maternal age and level of anti-thyroid antibodies were used to predict thyroid functional impairment.

Thyroid Function and Obesity

PubMed Central

Laurberg, Peter; Knudsen, Nils; Andersen, Stig; Carlé, Allan; Pedersen, Inge Bülow; Karmisholt, Jesper

2012-01-01

Important interaction exists between thyroid function, weight control, and obesity. Several mechanisms seem to be involved, and in studies of groups of people the pattern of thyroid function tests depends on the balance of obesity and underlying thyroid disease in the cohort studied. Obese people with a normal thyroid gland tend to have activation of the hypothalamic-pituitary-thyroid axis with higher serum TSH and thyroid hormones in serum. On the other hand, small differences in thyroid function are associated with up to 5 kg difference in body weight. The weight loss after therapy of overt hypothyroidism is caused by excretion of water bound in tissues (myxoedema). Many patients treated for hyperthyroidism experience a gain of more weight than they lost during the active phase of the disease. The mechanism for this excessive weight gain has not been fully elucidated. New studies on the relation between L-T3 therapy and weight control are discussed. The interaction between weight control and therapy of thyroid disease is important to many patients and it should be studied in more detail. PMID:24783015

Development of a functional thyroid model based on an organoid culture system.

PubMed

Saito, Yoshiyuki; Onishi, Nobuyuki; Takami, Hiroshi; Seishima, Ryo; Inoue, Hiroyoshi; Hirata, Yuki; Kameyama, Kaori; Tsuchihashi, Kenji; Sugihara, Eiji; Uchino, Shinya; Ito, Koichi; Kawakubo, Hirofumi; Takeuchi, Hiroya; Kitagawa, Yuko; Saya, Hideyuki; Nagano, Osamu

2018-03-04

The low turnover rate of thyroid follicular cells and the lack of a long-term thyroid cell culture system have hampered studies of thyroid carcinogenesis. We have now established a thyroid organoid culture system that supports thyroid cell proliferation in vitro. The established mouse thyroid organoids performed thyroid functions including thyroglobulin synthesis, iodide uptake, and the production and release of thyroid hormone. Furthermore, transplantation of the organoids into recipient mice resulted in the formation of normal thyroid-like tissue capable of iodide uptake and thyroglobulin production in vivo. Finally, forced expression of oncogenic NRAS (NRAS Q61R ) in thyroid organoids established from p53 knockout mice and transplantation of the manipulated organoids into mouse recipients generated a model of poorly differentiated thyroid cancer. Our findings suggest that this newly developed thyroid organoid culture system is a potential research tool for the study of thyroid physiology and pathology including thyroid cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

Partial thyrocyte-specific Gαs deficiency leads to rapid-onset hypothyroidism, hyperplasia, and papillary thyroid carcinoma-like lesions in mice.

PubMed

Patyra, Konrad; Jaeschke, Holger; Löf, Christoffer; Jännäri, Meeri; Ruohonen, Suvi T; Undeutsch, Henriette; Khalil, Moosa; Kero, Andreina; Poutanen, Matti; Toppari, Jorma; Chen, Min; Weinstein, Lee S; Paschke, Ralf; Kero, Jukka

2018-05-25

Thyroid function is controlled by thyroid-stimulating hormone (TSH), which binds to its G protein-coupled receptor [thyroid-stimulating hormone receptor (TSHR)] on thyrocytes. TSHR can potentially couple to all G protein families, but it mainly activates the G s - and G q/11 -mediated signaling cascades. To date, there is a knowledge gap concerning the role of the individual G protein cascades in thyroid pathophysiology. Here, we demonstrate that the thyrocyte-specific deletion of G s -protein α subunit (Gα s ) in adult mice [tamoxifen-inducible G s protein α subunit deficient (iTGα s KO) mice] rapidly impairs thyrocyte function and leads to hypothyroidism. Consequently, iTGα s KO mice show reduced food intake and activity. However, body weight and the amount of white adipose tissue were decreased only in male iTGα s KO mice. Unexpectedly, hyperplastic follicles and papillary thyroid cancer-like tumor lesions with increased proliferation and slightly increased phospho-ERK1/2 staining were found in iTGα s KO mice at an older age. These tumors developed from nonrecombined thyrocytes still expressing Gα s in the presence of highly elevated serum TSH. In summary, we report that partial thyrocyte-specific Gα s deletion leads to hypothyroidism but also to tumor development in thyrocytes with remaining Gα s expression. Thus, these mice are a novel model to elucidate the pathophysiological consequences of hypothyroidism and TSHR/G s /cAMP-mediated tumorigenesis.-Patyra, K., Jaeschke, H., Löf, C., Jännäri, M., Ruohonen, S. T., Undeutsch, H., Khalil, M., Kero, A., Poutanen, M., Toppari, J., Chen, M., Weinstein, L. S., Paschke, R., Kero, J. Partial thyrocyte-specific Gα s deficiency leads to rapid-onset hypothyroidism, hyperplasia, and papillary thyroid carcinoma-like lesions in mice.

Flavonoid Fraction of Citrus reticulata Juice Reduces Proliferation and Migration of Anaplastic Thyroid Carcinoma Cells.

PubMed

Celano, Marilena; Maggisano, Valentina; De Rose, Roberta Francesca; Bulotta, Stefania; Maiuolo, Jessica; Navarra, Michele; Russo, Diego

2015-01-01

Effects of flavonoids extracted from Citrus reticulata (mandarin) juice on proliferation and migration of 3 human anaplastic thyroid carcinoma (ATC) cell lines were evaluated. Flavonoid components of Mandarin juice extract (MJe) were analyzed by uHPLC. Proliferation of CAL-62, C-643, and 8505C cells, measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, was significantly reduced by MJe in a concentration- and time-dependent way, with maximal effect elicited at 0.5 mg/ml concentration after 48 h. Cytofluorimetric analysis showed a block in the G2/M phase of the cell cycle, accompanied by low cell mortality owed to autophagic death. The extract caused also a reduction of cell migration, associated with decreased activity of the metalloproteinase MMP-2. These findings demonstrate that the flavonoid fraction of mandarin juice exerts in vitro antiproliferative effects on ATC cells, associated with a reduction of migration, suggesting for such a functional food a potential use as adjuvant in the treatment of thyroid cancer.

Influence of thyroid in nervous system growth.

PubMed

Mussa, G C; Mussa, F; Bretto, R; Zambelli, M C; Silvestro, L

2001-08-01

Nervous system growth and differentiation are closely correlated with the presence of iodine and thyroid hormones in initial development stages. In the human species, encephalon maturation during the first quarter of pregnancy is affected according to recent studies by the transplacenta passage of maternal thyroid hormones while it depends on initial iodiothyronin secretion by the foetal gland after the 12th week of pregnancy. Thyroid hormone deficiency during nervous system development causes altered noble nervous cells, such as the pyramidal cortical and Purkinje cells, during glial cell proliferation and differentiation alike. Neurons present cell hypoplasia with reduced axon count, dendritic branching, synaptic spikes and interneuron connections. Oligodendrocytes decrease in number and average myelin content consequently drops. Biochemical studies on hypothyroid rats have demonstrated alterations to neuron intraplasmatic microtubule content and organisation, changed mitochondria number and arrangement and anomalies in T3 nuclear and citoplasmatic receptor maturation. Alterations to microtubules are probably responsible for involvement of the axon-dendrite system, and are the consequence of deficient thyroid hormone action on the mitochondria, the mitochondria enzymes and proteins associated with microtubules. Nuclear and citoplasmatic receptors have been identified and gene clonation studies have shown two families of nuclear receptors that include several sub-groups in their turn. A complex scheme of temporal and spatial expression of these receptors exists, so they probably contribute with one complementary function, although their physiological role differs. The action of thyroid hormones occurs by changing cell protein levels because of their regulation at the transcriptional or post-transcriptional level. Genes submitted to thyroid hormone control are either expressed by oligodendrytes, which are myelin protein coders or glial differentiation mediators, or are nervous cell specific, genes coding neurotropins or proteins involved in synaptic excitation. The use of new PMRS and MRI non-invasive techniques has enabled identification of metabolic and biochemical markers for alterations in the encephalon of untreated hypothyroid children. Even an excess of thyroid hormones during early nervous system development can cause permanent effects. Hyperthyroidism in fact initially induces accelerated maturation process including cell migration and differentiation, extension of dendritic processes and synaptogenesis but a later excess of thyroid hormones causes reduction of the total number of dendritic spikes, due to early interruption of neuron proliferation. Experimental studies and clinical research have clarified not only the correlation between nervous system maturation and thyroid function during early development stages and the certain finding from this research is that both excess and deficient thyroid hormones can cause permanent anatomo-functional alterations to the nervous system.

CO-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women.

PubMed

Horton, Megan K; Blount, Benjamin C; Valentin-Blasini, Liza; Wapner, Ronald; Whyatt, Robin; Gennings, Chris; Factor-Litvak, Pam

2015-11-01

Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancy We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New York City using weighted quantile sum (WQS) regression. We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (±2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine. Individual analyte concentrations in urine were significantly correlated (Spearman's r 0.4-0.5, p<0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS. Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Co-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women

PubMed Central

Horton, Megan K.; Blount, Benjamin C.; Valentin-Blasini, Liza; Wapner, Ronald; Whyatt, Robin; Gennings, Chris; Factor-Litvak, Pam

2015-01-01

Background Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancy. Objectives We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New York City using weighted quantile sum (WQS) regression. Methods We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (± 2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine. Results Individual analyte concentrations in urine were significantly correlated (Spearman’s r 0.4–0.5, p < 0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS. Conclusions Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy. PMID:26408806

Transient hyperthyroidism of hyperemesis gravidarum.

PubMed

Tan, Jackie Y L; Loh, Keh Chuan; Yeo, George S H; Chee, Yam Cheng

2002-06-01

To characterise the clinical, biochemical and thyroid antibody profile in women with transient hyperthyroidism of hyperemesis gravidarum. Prospective observational study. Hospital inpatient gynaecological ward. Women admitted with hyperemesis gravidarum and found to have hyperthyroidism. Fifty-three women were admitted with hyperemesis gravidarum and were found to have hyperthyroidism. Each woman was examined for clinical signs of thyroid disease and underwent investigations including urea, creatinine, electrolytes, liver function test, thyroid antibody profile and serial thyroid function test until normalisation. Gestation at which thyroid function normalised, clinical and thyroid antibody profile and pregnancy outcome (birthweight, gestation at delivery and Apgar score at 5 minutes). Full data were available for 44 women. Free T4 levels normalised by 15 weeks of gestation in the 39 women with transient hyperthyroidism while TSH remained suppressed until 19 weeks of gestation. None of these women were clinically hyperthyroid. Thyroid antibodies were not found in most of them. Median birthweight in the infants of mothers who experienced weight loss of > 5% of their pre-pregnancy weight was lower compared with those of women who did not (P = 0.093). Five women were diagnosed with Graves' disease based on clinical features and thyroid antibody profile. In transient hyperthyroidism of hyperemesis gravidarum, thyroid function normalises by the middle of the second trimester without anti-thyroid treatment. Clinically overt hyperthyroidism and thyroid antibodies are usually absent. Apart from a non-significant trend towards lower birthweights in the infants of mothers who experienced significant weight loss, pregnancy outcome was generally good. Routine assessment of thyroid function is unnecessary for women with hyperemesis gravidarum in the absence of any clinical features of hyperthyroidism.

Thyroid Nodules

MedlinePlus

... disorder, can cause thyroid inflammation resulting in nodular enlargement. This often is associated with reduced thyroid gland ... Goiter" is a term used to describe any enlargement of the thyroid gland, which can be caused ...

Arterial hypertension and thyroid disorders: what is important to know in clinical practice?

PubMed

Mazza, A; Beltramello, G; Armigliato, M; Montemurro, D; Zorzan, S; Zuin, M; Rampin, L; Marzola, M C; Grassetto, G; Al-Nahhas, A; Rubello, D

2011-09-01

This review describes the pathogenic mechanisms of blood pressure (BP) regulation and long-term control in thyroid disorders. Variations from the euthyroid status affect virtually all physiological systems but the effects on the cardiovascular system are particularly pronounced. Thyroid disorders induce several hemodynamic changes leading to elevated BP as a consequence of their interaction with endothelial function, vascular reactivity, renal hemodynamic and renin-angiotensin system. However, in thyroid disorders, the regulation of BP and the development and maintenance of variable forms of arterial hypertension (HT) are different. Hyperthyroidism results in an increased endothelium-dependent responsiveness secondary to the shear stress induced by the hyperdynamic circulation, and contributes to reduce vascular resistance. Conversely, hypothyroidism is accompanied by a marked decrease in sensitivity to sympathetic agonists with an increase of peripheral vascular resistance and arterial stiffness. Furthermore in animal models, hypothyroidism reduces the endothelium-dependent and nitric oxide-dependent vasodilatation. HT due to thyroid disorders is usually reversible with achievement of euthyroidism, but in some cases pharmacological treatment for BP control is required. In hyperthyroidism, β-blockers are the first-choice treatment to control BP but when they are contraindicated or not tolerated, ACE-inhibitors or calcium-channel blockers (CCB) are recommended. Hypothyroidism is a typical low rennin HT form showing a better antihypertensive response to CCB and diuretics; indeed in hypothyroidism a low-sodium diet seems further to improve BP control. Randomized clinical trials to compare the efficacy on BP control of the antihypertensive treatment in thyroid disorders are needed. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

[Metabolic disorders and nutritional status in autoimmune thyroid diseases].

PubMed

Kawicka, Anna; Regulska-Ilow, Bożena; Regulska-Ilow, Bożena

2015-01-02

In recent years, the authors of epidemiological studies have documented that autoimmune diseases are a major problem of modern society and are classified as diseases of civilization. Autoimmune thyroid diseases (ATDs) are caused by an abnormal immune response to autoantigens present in the thyroid gland - they often coexist with other autoimmune diseases. The most common dysfunctions of the thyroid gland are hypothyroidism, Graves-Basedow disease and Hashimoto's disease. Hashimoto's thyroiditis can be the main cause of primary hypothyroidism of the thyroid gland. Anthropometric, biochemical and physicochemical parameters are used to assess the nutritional status during the diagnosis and treatment of thyroid diseases. Patients with hypothyroidism are often obese, whereas patients with hyperthyroidism are often afflicted with rapid weight loss. The consequence of obesity is a change of the thyroid hormones' activity; however, weight reduction leads to their normalization. The activity and metabolic rate of thyroid hormones are modifiable. ATDs are associated with abnormalities of glucose metabolism and thus increased risk of developing diabetes mellitus type 1 and type 2. Celiac disease (CD) also increases the risk of developing other autoimmune diseases. Malnutrition or the presence of numerous nutritional deficiencies in a patient's body can be the cause of thyroid disorders. Coexisting deficiencies of such elements as iodine, iron, selenium and zinc may impair the function of the thyroid gland. Other nutrient deficiencies usually observed in patients suffering from ATD are: protein deficiencies, vitamin deficiencies (A, C, B6, B5, B1) and mineral deficiencies (phosphorus, magnesium, potassium, sodium, chromium). Proper diet helps to reduce the symptoms of the disease, maintains a healthy weight and prevents the occurrence of malnutrition. This article presents an overview of selected documented studies and scientific reports on the relationship of metabolic disorders and nutritional status with the occurrence of ATD.

A Rapid CRISPR/Cas-based Mutagenesis Assay in Zebrafish for Identification of Genes Involved in Thyroid Morphogenesis and Function.

PubMed

Trubiroha, A; Gillotay, P; Giusti, N; Gacquer, D; Libert, F; Lefort, A; Haerlingen, B; De Deken, X; Opitz, R; Costagliola, S

2018-04-04

The foregut endoderm gives rise to several organs including liver, pancreas, lung and thyroid with important roles in human physiology. Understanding which genes and signalling pathways regulate their development is crucial for understanding developmental disorders as well as diseases in adulthood. We exploited unique advantages of the zebrafish model to develop a rapid and scalable CRISPR/Cas-based mutagenesis strategy aiming at the identification of genes involved in morphogenesis and function of the thyroid. Core elements of the mutagenesis assay comprise bi-allelic gene invalidation in somatic mutants, a non-invasive monitoring of thyroid development in live transgenic fish, complementary analyses of thyroid function in fixed specimens and quantitative analyses of mutagenesis efficiency by Illumina sequencing of individual fish. We successfully validated our mutagenesis-phenotyping strategy in experiments targeting genes with known functions in early thyroid morphogenesis (pax2a, nkx2.4b) and thyroid functional differentiation (duox, duoxa, tshr). We also demonstrate that duox and duoxa crispants phenocopy thyroid phenotypes previously observed in human patients with bi-allelic DUOX2 and DUOXA2 mutations. The proposed combination of efficient mutagenesis protocols, rapid non-invasive phenotyping and sensitive genotyping holds great potential to systematically characterize the function of larger candidate gene panels during thyroid development and is applicable to other organs and tissues.

Combined effects of perchlorate, thiocyanate, and iodine on thyroid function in the National Health and Nutrition Examination Survey 2007–08

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinmaus, Craig, E-mail: craigs@berkeley.edu; Miller, Mark D., E-mail: ucsfpehsumiller@gmail.com; Cushing, Lara, E-mail: lara.cushing@berkeley.edu

Perchlorate, thiocyanate, and low iodine intake can all decrease iodide intake into the thyroid gland. This can reduce thyroid hormone production since iodide is a key component of thyroid hormone. Previous research has suggested that each of these factors alone may decrease thyroid hormone levels, but effect sizes are small. We hypothesized that people who have all three factors at the same time have substantially lower thyroid hormone levels than people who do not, and the effect of this combined exposure is substantially larger than the effects seen in analyses focused on only one factor at a time. Using datamore » from the 2007–2008 National Health and Nutrition Examination Survey, subjects were categorized into exposure groups based on their urinary perchlorate, iodine, and thiocyanate concentrations, and mean serum thyroxine concentrations were compared between groups. Subjects with high perchlorate (n=1939) had thyroxine concentrations that were 5.0% lower (mean difference=0.40 μg/dl, 95% confidence interval=0.14–0.65) than subjects with low perchlorate (n=2084). The individual effects of iodine and thiocyanate were even smaller. Subjects with high perchlorate, high thiocyanate, and low iodine combined (n=62) had thyroxine concentrations 12.9% lower (mean difference=1.07 μg/dl, 95% confidence interval=0.55–1.59) than subjects with low perchlorate, low thiocyanate, and adequate iodine (n=376). Potential confounders had little impact on results. Overall, these results suggest that concomitant exposure to perchlorate, thiocyanate, and low iodine markedly reduces thyroxine production. This highlights the potential importance of examining the combined effects of multiple agents when evaluating the toxicity of thyroid-disrupting agents. -- Highlights: ► Recent data suggest that essentially everyone in the US is exposed to perchlorate. ► Perchlorate exposure may be associated with lower thyroid hormone levels. ► Some groups may be more susceptible to perchlorate than others.« less

Thyroid nodules, thyroid function and dietary iodine in the Marshall islands.

PubMed

Takahashi, T; Fujimori, K; Simon, S L; Bechtner, G; Edwards, R; Trott, K R

1999-08-01

Thyroid nodules have been found to be common in the population of the Marshall Islands. This has been attributed to potential exposure of radioiodines from the nuclear weapons tests on Bikini and Eniwetok between 1946 and 1958. In order to get a full picture of thyroid pathology in the Marshallese population potentially exposed to radioactive fallout we performed a large thyroid screening programme using palpation, high resolution ultrasound and fine needle biopsies of palpable nodules. In addition, various parameters of thyroid function (free T3, free T4, thyroid stimulating hormone [TSH]) and anti-thyroid antibodies were examined in large proportions of the total population at risk. Since dietary iodine deficiency is an established risk factor for thyroid nodules, iodine concentration in urine samples of 362 adults and 119 children was measured as well as the iodine content of selected staple food products. The expected high prevalence of thyroid nodules was confirmed. There was no indication of an increased rate of impaired thyroid function in the Marshallese population. A moderate degree of iodine deficiency was found which may be responsible for some of the increased prevalence of thyroid nodules in the Marshallese population. Studies on the relationship between exposure to radioiodines and thyroid nodules need to take dietary iodine deficiency into account in the interpretation of findings.

CO-occurring exposure to perchlorate, nitrate and thiocyanate alters thyroid function in healthy pregnant women

DOE Office of Scientific and Technical Information (OSTI.GOV)

Horton, Megan K., E-mail: megan.horton@mssm.edu; Blount, Benjamin C.; Valentin-Blasini, Liza

Background: Adequate maternal thyroid function during pregnancy is necessary for normal fetal brain development, making pregnancy a critical window of vulnerability to thyroid disrupting insults. Sodium/iodide symporter (NIS) inhibitors, namely perchlorate, nitrate, and thiocyanate, have been shown individually to competitively inhibit uptake of iodine by the thyroid. Several epidemiologic studies examined the association between these individual exposures and thyroid function. Few studies have examined the effect of this chemical mixture on thyroid function during pregnancy Objectives: We examined the cross sectional association between urinary perchlorate, thiocyanate and nitrate concentrations and thyroid function among healthy pregnant women living in New Yorkmore » City using weighted quantile sum (WQS) regression. Methods: We measured thyroid stimulating hormone (TSH) and free thyroxine (FreeT4) in blood samples; perchlorate, thiocyanate, nitrate and iodide in urine samples collected from 284 pregnant women at 12 (±2.8) weeks gestation. We examined associations between urinary analyte concentrations and TSH or FreeT4 using linear regression or WQS adjusting for gestational age, urinary iodide and creatinine. Results: Individual analyte concentrations in urine were significantly correlated (Spearman's r 0.4–0.5, p<0.001). Linear regression analyses did not suggest associations between individual concentrations and thyroid function. The WQS revealed a significant positive association between the weighted sum of urinary concentrations of the three analytes and increased TSH. Perchlorate had the largest weight in the index, indicating the largest contribution to the WQS. Conclusions: Co-exposure to perchlorate, nitrate and thiocyanate may alter maternal thyroid function, specifically TSH, during pregnancy. - Highlights: • Perchlorate, nitrate, thiocyanate and iodide measured in maternal urine. • Thyroid function (TSH and Free T4) measured in maternal blood. • Weighted quantile sum (WQS) regression examined complex mixture effect. • WQS identified an inverse association between the exposure mixture and maternal TSH. • Perchlorate indicated as the ‘bad actor’ of the mixture.« less

A review on cardiovascular diseases originated from subclinical hypothyroidism.

PubMed

Mansourian, Azad Reza

2012-01-15

Thyroid hormones play an important role on the cardiovascular systems and thyroid disorder ultimately have a profound adverse effects on myocardium and vascular functions. There are extensive reports on the role of overt thyroid dysfunction which adversely can modify the cardiovascular metabolism but even at the present of some controversial reports, the subclinical thyroid disorders are able also to manipulate cardiovascular system to some extent. The aim of this study is to review the cardiovascular disorders accompanied with subclinical hypothyroidism. It is concluded that adverse effect of thyroid malfunction on myocardium and vascular organs are through the direct role of thyroid hormone and dyslipidemia on heart muscle cells at nuclear level and vascular system, respectively. It seems many cardiovascular disorders initially would not have been occurred in the first place if the thyroid of affected person had functioned properly, therefore thyroid function tests should be one of a prior laboratory examinations in cardiovascular disorders.

Update on the Management of Thyroid Disease during Pregnancy.

PubMed

Yim, Chang Hoon

2016-09-01

Thyroid dysfunction during pregnancy can result in serious complications for both the mother and infant; however, these complications can be prevented by optimal treatment of maternal overt thyroid dysfunction. Although several studies have demonstrated that maternal subclinical hypothyroidism is associated with obstetric complications and neurocognitive impairments in offspring, there is limited evidence that levothyroxine treatment can improve these complications. Therefore, most professional societies do not recommend universal screening for thyroid dysfunction during pregnancy, and instead recommend a case-finding approach in which only high-risk women are tested. However, recent studies have estimated that targeted thyroid function testing misses approximately 30% to 55% of hypothyroidism cases in pregnant women, and some associations and researchers have recommended universal screening of pregnant women to facilitate the early detection and treatment of overt hypothyroidism. This review summarizes recent data on thyroid function test changes, thyroid functional disorder management, and thyroid screening during pregnancy.

Subclinical hypothyroidism in patients with non-alcoholic fatty liver disease at the background of carbohydrate metabolism disorders.

PubMed

Feisa, Snizhana V; Chopei, Ivan V

2018-01-01

Introduction: The prevalence of non-alcoholic fatty liver disease (NAFLD) is 25-30% in the general population and more than 75% among patients with carbohydrate metabolism disorders. One in six patients with NAFLD has concomitant subclinical hypothyroidism. The aim is to compare lipid and carbohydrate metabolism states in patients with NAFLD depending on the functional state of the thyroid gland. Materials and methods:215 patients with NAFLD and type 2 diabetes mellitus (T2-DM) or pre-diabetes (PD) were involved in study and devided into 6 groups according to the functional state of the thyroid gland. Results: In cases of adding subclinical hypothyroidism systolic and diastolic blood pressure are rising. In patients with overt hypothyroidism average HOMA-IR index is 29,98±1,05, which exceeds the corresponding figure in patients with concomitant subclinical hypothyroidism. In patients whose hypothyroidism has been compensated by levothyroxine, HOMA-IR index was reduced to 18,56±1,58, indicating a tendency to restore the sensitivity of peripheral tissues to insulin, on the assumption under the medicatedcorrection of thyroid functional status. Levels of common cholesterol and triglycerides were higher in cases of NAFLD with subclinical or overt hypothyroidism than in patients with NAFLD and normal thyroid function. Replacement therapy by levothyroxine leads to improving of lipid changes in patients with NAFLD and concomitant overt hypothyroidism: the levels of common cholesterol and triglycerides were reducing from 6,04±1,18 mmol/l and 3,96±1,34 mmol/l to 5,97±1,1 mmol/l and 3,45±1,13 mmol/l in accordance. Conclusions: Concomitant subclinical hypothyroidism in patients with NAFLD at the background of carbohydrate metabolism disorders leads to atherogenic dyslipidemia, increasing of blood atherogenicity. The index of lipid accumulated product (LAP) and the resistance of peripheral tissues to insulin also increases.

Colchicum autumnale in Patients with Goitre with Euthyroidism or Mild Hyperthyroidism: Indications for a Therapeutic Regulative Effect—Results of an Observational Study

PubMed Central

Scheffer, Christian; Debus, Marion; Heckmann, Christian; Cysarz, Dirk; Girke, Matthias

2016-01-01

Introduction. Goitre with euthyroid function or with subclinical or mild hyperthyroidism due to thyroid autonomy is common. In anthroposophic medicine various thyroid disorders are treated with Colchicum autumnale (CAU). We examined the effects of CAU in patients with goitre of both functional states. Patients and methods. In an observational study, 24 patients with goitre having suppressed thyroid stimulating hormone (TSH) levels with normal or slightly elevated free thyroxine (fT4) and free triiodothyronine (fT3) (group 1, n = 12) or normal TSH, fT3, and fT4 (group 2, n = 12) were included. After 3 months and after 6 to 12 months of CAU treatment, we investigated clinical pathology using the Hyperthyroid Symptom Scale (HSS), hormone status (TSH, fT4, and fT3), and thyroidal volume (tV). Results. After treatment with CAU, in group 1 the median HSS decreased from 4.5 (2.3–11.8) to 2 (1.3–3) (p < 0.01) and fT3 decreased from 3.85 (3.5–4.78) to 3.45 (3.3–3.78) pg/mL (p < 0.05). In group 2 tV (13.9% (18.5%–6.1%)) and TSH (p < 0.01) were reduced. Linear regression for TSH and fT3 in both groups indicated a regulative therapeutic effect of CAU. Conclusions. CAU positively changed the clinical pathology of subclinical hyperthyroidism and thyroidal volume in patients with euthyroid goitre by normalization of the regulation of thyroidal hormones. PMID:26955394

Colchicum autumnale in Patients with Goitre with Euthyroidism or Mild Hyperthyroidism: Indications for a Therapeutic Regulative Effect-Results of an Observational Study.

PubMed

Scheffer, Christian; Debus, Marion; Heckmann, Christian; Cysarz, Dirk; Girke, Matthias

2016-01-01

Introduction. Goitre with euthyroid function or with subclinical or mild hyperthyroidism due to thyroid autonomy is common. In anthroposophic medicine various thyroid disorders are treated with Colchicum autumnale (CAU). We examined the effects of CAU in patients with goitre of both functional states. Patients and methods. In an observational study, 24 patients with goitre having suppressed thyroid stimulating hormone (TSH) levels with normal or slightly elevated free thyroxine (fT4) and free triiodothyronine (fT3) (group 1, n = 12) or normal TSH, fT3, and fT4 (group 2, n = 12) were included. After 3 months and after 6 to 12 months of CAU treatment, we investigated clinical pathology using the Hyperthyroid Symptom Scale (HSS), hormone status (TSH, fT4, and fT3), and thyroidal volume (tV). Results. After treatment with CAU, in group 1 the median HSS decreased from 4.5 (2.3-11.8) to 2 (1.3-3) (p < 0.01) and fT3 decreased from 3.85 (3.5-4.78) to 3.45 (3.3-3.78) pg/mL (p < 0.05). In group 2 tV (13.9% (18.5%-6.1%)) and TSH (p < 0.01) were reduced. Linear regression for TSH and fT3 in both groups indicated a regulative therapeutic effect of CAU. Conclusions. CAU positively changed the clinical pathology of subclinical hyperthyroidism and thyroidal volume in patients with euthyroid goitre by normalization of the regulation of thyroidal hormones.

High Body Mass Index Is an Indicator of Maternal Hypothyroidism, Hypothyroxinemia, and Thyroid-Peroxidase Antibody Positivity during Early Pregnancy

PubMed Central

Han, Cheng; Li, Chenyan; Mao, Jinyuan; Wang, Weiwei; Xie, Xiaochen; Zhou, Weiwei; Li, Chenyang; Xu, Bin; Bi, Lihua; Meng, Tao; Du, Jianling; Zhang, Shaowei; Gao, Zhengnan; Zhang, Xiaomei; Yang, Liu; Fan, Chenling; Teng, Weiping; Shan, Zhongyan

2015-01-01

Background. Maternal thyroid dysfunction in early pregnancy may increase the risk of adverse pregnancy complications and neurocognitive deficiencies in the developing fetus. Currently, some researchers demonstrated that body mass index (BMI) is associated with thyroid function in nonpregnant population. Hence, the American Thyroid Association recommended screening thyroid function in obese pregnant women; however, the evidence for this is weak. For this purpose, our study investigated the relationship between high BMI and thyroid functions during early pregnancy in Liaoning province, an iodine-sufficient region of China. Methods. Serum thyroid stimulating hormone (TSH), free thyroxine (FT4), thyroid-peroxidase antibody (TPOAb), thyroglobulin antibody (TgAb) concentration, urinary iodine concentration (UIC), and BMI were determined in 6303 pregnant women. Results. BMI ≥ 25 kg/m2 may act as an indicator of hypothyroxinemia and TPOAb positivity and BMI ≥ 30 kg/m2 was associated with increases in the odds of hypothyroidism, hypothyroxinemia, and TPOAb positivity. The prevalence of isolated hypothyroxinemia increased among pregnant women with BMI > 24 kg/m2. Conclusions. High BMI during early pregnancy may be an indicator of maternal thyroid dysfunction; for Asian women whose BMI > 24 kg/m2 and who are within 8 weeks of pregnancy, thyroid functions should be assessed especially. PMID:26273610

Quantitative single-photon emission computed tomography/computed tomography for technetium pertechnetate thyroid uptake measurement

PubMed Central

Lee, Hyunjong; Kim, Ji Hyun; Kang, Yeon-koo; Moon, Jae Hoon; So, Young; Lee, Won Woo

2016-01-01

Abstract Objectives: Technetium pertechnetate (99mTcO4) is a radioactive tracer used to assess thyroid function by thyroid uptake system (TUS). However, the TUS often fails to deliver accurate measurements of the percent of thyroid uptake (%thyroid uptake) of 99mTcO4. Here, we investigated the usefulness of quantitative single-photon emission computed tomography/computed tomography (SPECT/CT) after injection of 99mTcO4 in detecting thyroid function abnormalities. Materials and methods: We retrospectively reviewed data from 50 patients (male:female = 15:35; age, 46.2 ± 16.3 years; 17 Graves disease, 13 thyroiditis, and 20 euthyroid). All patients underwent 99mTcO4 quantitative SPECT/CT (185 MBq = 5 mCi), which yielded %thyroid uptake and standardized uptake value (SUV). Twenty-one (10 Graves disease and 11 thyroiditis) of the 50 patients also underwent conventional %thyroid uptake measurements using a TUS. Results: Quantitative SPECT/CT parameters (%thyroid uptake, SUVmean, and SUVmax) were the highest in Graves disease, second highest in euthyroid, and lowest in thyroiditis (P < 0.0001, Kruskal–Wallis test). TUS significantly overestimated the %thyroid uptake compared with SPECT/CT (P < 0.0001, paired t test) because other 99mTcO4 sources in addition to thyroid, such as salivary glands and saliva, contributed to the %thyroid uptake result by TUS, whereas %thyroid uptake, SUVmean and SUVmax from the SPECT/CT were associated with the functional status of thyroid. Conclusions: Quantitative SPECT/CT is more accurate than conventional TUS for measuring 99mTcO4 %thyroid uptake. Quantitative measurements using SPECT/CT may facilitate more accurate assessment of thyroid tracer uptake. PMID:27399139

Common variants in the G protein beta3 subunit gene and thyroid disorders in a formerly iodine-deficient population.

PubMed

Völzke, Henry; Bornhorst, Alexa; Rimmbach, Christian; Petersenn, Holger; Geissler, Ingrid; Nauck, Matthias; Wallaschofski, Henri; Kroemer, Heyo K; Rosskopf, Dieter

2009-10-01

Heterotrimeric G proteins are key mediators of signals from membrane receptors-including the thyroid-stimulating hormone (TSH) receptor-to cellular effectors. Gain-of-function mutations in the TSH receptor and the Galpha(S) subunit occur frequently in hyperfunctioning thyroid nodules and differentiated thyroid carcinomas, whereby the T allele of a common polymorphism (825C>T, rs5443) in the G protein beta3 subunit gene (GNB3) is associated with increased G protein-mediated signal transduction and a complex phenotype. The aim of this study was to investigate whether this common polymorphism affects key parameters of thyroid function and morphology and influences the pathogenesis of thyroid diseases in the general population. The population-based cross-sectional Study of Health in Pomerania is a general health survey with focus on thyroid diseases in northeast Germany, a formerly iodine-deficient area. Data from 3428 subjects (1800 men and 1628 women) were analyzed for an association of the GNB3 genotype with TSH, free triiodothyronine and thyroxine levels, urine iodine and thiocyanate excretion, and thyroid ultrasound morphology including thyroid volume, presence of goiter, and thyroid nodules. There was no association between GNB3 genotype status and the functional or morphological thyroid parameters investigated, neither in crude analyses nor upon multivariable analyses including known confounders of thyroid disorders. Based on the data from this large population-based survey, we conclude that the GNB3 825C>T polymorphism does not affect key parameters of thyroid function and morphology in the general population of a formerly iodine-deficient area.

Sorafenib induced thyroiditis in two patients with hepatocellular carcinoma.

PubMed

van Doorn, Leni; Eskens, Ferry A L M; Visser, Theo J; van der Lugt, Aad; Mathijssen, Ron H J; Peeters, Robin P

2011-02-01

Sorafenib is a multi-targeted tyrosine kinase inhibitor licensed for the treatment of hepatocellular carcinoma and renal cell carcinoma. Thyroid function test abnormalities have been reported for different tyrosine kinase inhibitors, but only limited data on thyroid function test abnormalities related to sorafenib are available, demonstrating the occurrence of hypothyroidism in patients treated with sorafenib. We describe two patients who developed temporary hyperthyroidism during the course of sorafenib treatment, which was followed by overt and subclinical hypothyroidism, respectively. Thyroid ultrasonography showed an atrophic thyroid gland in patient 1 , and signs of thyroiditis in patient 2 . Detailed reassessment of thyroid volumes on routinely performed computerized tomography scans showed a gradual decrease in thyroid volume during sorafenib treatment in one patient, suggesting progressive thyroid destruction. This case report describes in detail and for the first time two cases of sorafenib-induced thyroiditis. We assume that this sorafenib-induced destructive thyroiditis is an important cause of sorafenib-induced hypothyroidism.

Deletion of the Ttf1 gene in differentiated neurons disrupts female reproduction without impairing basal ganglia function.

PubMed

Mastronardi, Claudio; Smiley, Gregory G; Raber, Jacob; Kusakabe, Takashi; Kawaguchi, Akio; Matagne, Valerie; Dietzel, Anja; Heger, Sabine; Mungenast, Alison E; Cabrera, Ricardo; Kimura, Shioko; Ojeda, Sergio R

2006-12-20

Thyroid transcription factor 1 (TTF1) [also known as Nkx2.1 (related to the NK-2 class of homeobox genes) and T/ebp (thyroid-specific enhancer-binding protein)], a homeodomain gene required for basal forebrain morphogenesis, remains expressed in the hypothalamus after birth, suggesting a role in neuroendocrine function. Here, we show an involvement of TTF1 in the control of mammalian puberty and adult reproductive function. Gene expression profiling of the nonhuman primate hypothalamus revealed that TTF1 expression increases at puberty. Mice in which the Ttf1 gene was ablated from differentiated neurons grew normally and had normal basal ganglia/hypothalamic morphology but exhibited delayed puberty, reduced reproductive capacity, and a short reproductive span. These defects were associated with reduced hypothalamic expression of genes required for sexual development and deregulation of a gene involved in restraining puberty. No extrapyramidal impairments associated with basal ganglia dysfunction were apparent. Thus, although TTF1 appears to fulfill only a morphogenic function in the ventral telencephalon, once this function is satisfied in the hypothalamus, TTF1 remains active as part of the transcriptional machinery controlling female sexual development.

Laparoscopic gastric bypass in patients on thyroid replacement therapy for subnormal thyroid function - prevalence and short-term outcome.

PubMed

Szomstein, Samuel; Avital, Shmuel; Brasesco, Oscar; Mehran, Amir; Cabral, Jose M; Rosenthal, Raul

2004-01-01

Hypothyroidism is associated with increased body weight. Weight gain may occur despite normal levels of serum thyroid stimulating hormone (TSH) and thyroxine (T4) achieved by replacement therapy. We evaluated the prevalence of patients on thyroid replacement for subnormal thyroid function who were operated on for morbid obesity and monitored their postoperative weight loss pattern. Data was identified from a prospectively accrued database of patients undergoing laparoscopic Roux-en-Y gastric bypass (LRYGBP) or laparoscopic adjustable gastric banding (LAGB) for morbid obesity from February 2000 to November 2001. All patients with subnormal thyroid function, diagnosed by past thyroid function tests and treated by an endocrinologist, who were on thyroid replacement therapy, were identified; 5 of these were matched for age, gender, preoperative body mass index (BMI) and surgical procedure (LRYGBP) to 5 non-hypothyroid patients. Weight loss at 3 and 9 months after surgery was compared between the 2 groups. 192 patients underwent LRYGBP (n=155) or LAGB (n=37). Of the 21 patients (10.9%) on thyroid replacement identified, 14 were primary, 4 were postablative, and 3 were post-surgical; 17 underwent LRYGBP. All patients had normal preoperative serum levels of TSH and T4. Comparison of the 2 matched groups of patients revealed no difference in weight loss at 3 and 9 months after surgery (P=1.0). The prevalence of euthyroid patients on thyroid replacement for subnormal thyroid function who undergo surgical intervention for morbid obesity is high. Short-term weight loss in these patients is comparable to normal thyroid patients. Longer follow-up may be necessary to demonstrate the weight loss pattern in this group.

Taurine ameliorated thyroid function in rats co-administered with chlorpyrifos and lead.

PubMed

Akande, Motunrayo Ganiyat; Shittu, Muftau; Uchendu, Chidiebere; Yaqub, Lukuman Surakat

2016-12-01

Chlorpyrifos is a widely used organophosphate insecticide for domestic, agricultural and industrial purposes. Lead is a toxic heavy metal and it is used for domestic and industrial purposes. Taurine is a semi essential amino acid with bioprotective properties. The aim of this study was to investigate the effects of taurine on thyroid function in Wistar rats co-administered with chlorpyrifos and lead. The rats were divided into 5 groups of 10 rats each. The first two groups were administered with distilled water and soya oil (1 ml/kg) respectively. The other groups received taurine (50 mg/kg), chlorpyrifos + lead [chlorpyrifos (4.25 mg/kg, 1/20 median lethal dose] and lead (233.25 mg/kg, 1/20 median lethal dose) and taurine + chlorpyrifos + lead respectively. The treatments were administered once daily by oral gavage for 16 weeks. The rats were euthanized after the completion of the study and the thyroid function and thyroid histoarchitecture were evaluated. The results revealed that co-administration of chlorpyrifos and lead to the rats induced perturbations in thyroid function and this was manifested by reductions in the concentrations of triiodothyronine and thyroxine, increased thyroid stimulating hormone concentration and degeneration of the follicular epithelia of the thyroid gland. Taurine alleviated the perturbations in thyroid function and improved thyroid gland histoarchitecture. The beneficial effects of taurine may be attributed to its ability to protect the body from toxicity and oxidative stress. Taurine may be useful for prophylaxis against disruptions in thyroid function in animals that are exposed to environmental chlorpyrifos and lead.

Developmental Hypothyroidism Alters Brain-Derived Neurotrophic Factor (BDNF) Expression in Adulthood.

EPA Science Inventory

Severe developmental thyroid hormone (TH) insufficiency results in alterations in brain structure/function and lasting behavioral impairments. Environmental toxicants reduce circulating levels of TH, but the disruption is modest and the doseresponse relationships of TH and neuro...

Influence of thyroid function on glomerular filtration rate and other estimates of kidney function in two pediatric patients.

PubMed

Uemura, Osamu; Iwata, Naoyuki; Nagai, Takuhito; Yamakawa, Satoshi; Hibino, Satoshi; Yamamoto, Masaki; Nakano, Masaru; Tanaka, Kazuki

2018-05-01

To determine the optimal method of evaluating kidney function in patients with thyroid dysfunction, this study compared the estimated glomerular filtration rate derived from serum creatinine, cystatin C, or β2-microglobulin with inulin or creatinine clearance in two pediatric patients, one with hypothyroidism and the other with hyperthyroidism. It was observed that the kidney function decreased in a hypothyroid child and enhanced in a hyperthyroid child, with their kidney function becoming normalized by treatment with drugs, which normalized their thyroid function. Kidney function cannot be accurately evaluated using cystatin C-based or β2-microglobulin-based estimated glomerular filtration rate in patients with thyroid dysfunction, as these tests overestimated glomerular filtration rate in a patient with hypothyroidism and underestimated glomerular filtration rate in a patient with hyperthyroidism, perhaps through a metabolic rate-mediated mechanism. In both our patients, 24-h urinary creatinine secretion was identical before and after treatment, suggesting that creatinine production is not altered in patients with thyroid dysfunction. Therefore, kidney function in patients with thyroid dysfunction should be evaluated using creatinine-based estimated glomerular filtration rate.

Need of tetraiodothyronine supplemental therapy in pregnant women

NASA Astrophysics Data System (ADS)

Stoian, Dana; Craciunescu, Mihalea; Timar, Romulus; Schiller, Adalbert; Pater, Liana; Craina, Marius

2013-10-01

Thyroid hormones are essential for fetal development. Normal thyroid function in pregnant women adjusts by itself in cases of pregnancy, phenomenon that is deficient in cases of previous maternal thyroid disease. The study group was represented by 120 females, with reproductive age, with known thyroid disease, that had a up to delivery pregnancy. Thyroid ultrasound parameters and functional parameters were follow-up during the 9-month of gestation. The study proposes a mathematical model of predicting the need and the amount of tetraiodothyronine treatment in pregnant women with prevalent thyroid disease.

Diagnostic and functional structure of a high-resolution thyroid nodule clinic.

PubMed

Fernández-García, José Carlos; Mancha-Doblas, Isabel; Ortega-Jiménez, María Victoria; Ruiz-Escalante, José Francisco; Castells-Fusté, Ignasi; Tofé-Povedano, Santiago; Argüelles-Jiménez, Iñaki; Tinahones, Francisco José

2014-01-01

Appearance of a thyroid nodule has become a daily occurrence in clinical practice. Adequate thyroid nodule assessment requires several diagnostic tests and multiple medical appointments, which results in a substantial delay in diagnosis. Implementation of a high-resolution thyroid nodule clinic largely avoids these drawbacks by condensing in a single appointment all tests required for adequate evaluation of thyroid nodule. This paper reviews the diagnostic and functional structure of a high-resolution thyroid nodule clinic. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

GLIS3 is indispensable for TSH/TSHR-dependent thyroid hormone biosynthesis and follicular cell proliferation

PubMed Central

Kang, Hong Soon; Kumar, Dhirendra; Liao, Grace; Lichti-Kaiser, Kristin; Gerrish, Kevin; Liao, Xiao-Hui; Refetoff, Samuel; Jothi, Raja; Jetten, Anton M.

2017-01-01

Deficiency in Krüppel-like zinc finger transcription factor GLI-similar 3 (GLIS3) in humans is associated with the development of congenital hypothyroidism. However, the functions of GLIS3 in the thyroid gland and the mechanism by which GLIS3 dysfunction causes hypothyroidism are unknown. In the current study, we demonstrate that GLIS3 acts downstream of thyroid-stimulating hormone (TSH) and TSH receptor (TSHR) and is indispensable for TSH/TSHR-mediated proliferation of thyroid follicular cells and biosynthesis of thyroid hormone. Using ChIP-Seq and promoter analysis, we demonstrate that GLIS3 is critical for the transcriptional activation of several genes required for thyroid hormone biosynthesis, including the iodide transporters Nis and Pds, both of which showed enhanced GLIS3 binding at their promoters. The repression of cell proliferation of GLIS3-deficient thyroid follicular cells was due to the inhibition of TSH-mediated activation of the mTOR complex 1/ribosomal protein S6 (mTORC1/RPS6) pathway as well as the reduced expression of several cell division–related genes regulated directly by GLIS3. Consequently, GLIS3 deficiency in a murine model prevented the development of goiter as well as the induction of inflammatory and fibrotic genes during chronic elevation of circulating TSH. Our study identifies GLIS3 as a key regulator of TSH/TSHR-mediated thyroid hormone biosynthesis and proliferation of thyroid follicular cells and uncovers a mechanism by which GLIS3 deficiency causes neonatal hypothyroidism and prevents goiter development. PMID:29083325

Methodology and technical requirements of the galectin-3 test for the preoperative characterization of thyroid nodules.

PubMed

Bartolazzi, Armando; Bellotti, Carlo; Sciacchitano, Salvatore

2012-01-01

In the last decade, the β-galactosyl binding protein galectin-3 has been the object of extensive molecular, structural, and functional studies aimed to clarify its biological role in cancer. Multicenter studies also contributed to discover the potential clinical value of galectin-3 expression analysis in distinguishing, preoperatively, benign from malignant thyroid nodules. As a consequence galectin-3 is receiving significant attention as tumor marker for thyroid cancer diagnosis, but some conflicting results mostly owing to methodological problems have been published. The possibility to apply preoperatively a reliable galectin-3 test method on fine needle aspiration biopsy (FNA)-derived thyroid cells represents an important achievement. When correctly applied, the method reduces consistently the gray area of thyroid FNA cytology, contributing to avoid unnecessary thyroid surgery. Although the efficacy and reliability of the galectin-3 test method have been extensively proved in several studies, its translation in the clinical setting requires well-standardized reagents and procedures. After a decade of experimental work on galectin-3-related basic and translational research projects, the major methodological problems that may potentially impair the diagnostic performance of galectin-3 immunotargeting are highlighted and discussed in detail. A standardized protocol for a reliable galectin-3 expression analysis is finally provided. The aim of this contribution is to improve the clinical management of patients with thyroid nodules, promoting the preoperative use of a reliable galectin-3 test method as ancillary technique to conventional thyroid FNA cytology. The final goal is to decrease unnecessary thyroid surgery and its related social costs.

Excess Iodide Induces an Acute Inhibition of the Sodium/Iodide Symporter in Thyroid Male Rat Cells by Increasing Reactive Oxygen Species

PubMed Central

Arriagada, Alejandro A.; Albornoz, Eduardo; Opazo, Ma. Cecilia; Becerra, Alvaro; Vidal, Gonzalo; Fardella, Carlos; Michea, Luis; Carrasco, Nancy; Simon, Felipe; Elorza, Alvaro A.; Bueno, Susan M.; Kalergis, Alexis M.

2015-01-01

Na+/I− symporter (NIS) mediates iodide (I−) uptake in the thyroid gland, the first and rate-limiting step in the biosynthesis of the thyroid hormones. The expression and function of NIS in thyroid cells is mainly regulated by TSH and by the intracellular concentration of I−. High doses of I− for 1 or 2 days inhibit the synthesis of thyroid hormones, a process known as the Wolff-Chaikoff effect. The cellular mechanisms responsible for this physiological response are mediated in part by the inhibition of I− uptake through a reduction of NIS expression. Here we show that inhibition of I− uptake occurs as early as 2 hours or 5 hours after exposure to excess I− in FRTL-5 cells and the rat thyroid gland, respectively. Inhibition of I− uptake was not due to reduced NIS expression or altered localization in thyroid cells. We observed that incubation of FRTL-5 cells with excess I− for 2 hours increased H2O2 generation. Furthermore, the inhibitory effect of excess I− on NIS-mediated I− transport could be recapitulated by H2O2 and reverted by reactive derived oxygen species scavengers. The data shown here support the notion that excess I− inhibits NIS at the cell surface at early times by means of a posttranslational mechanism that involves reactive derived oxygen species. PMID:25594695

Thyroid peroxidase (TPO) expressed in thyroid and breast tissues shows similar antigenic properties

PubMed Central

Godlewska, Marlena; Arczewska, Katarzyna D.; Rudzińska, Magdalena; Łyczkowska, Anna; Krasuska, Wanda; Hanusek, Karolina; Ruf, Jean; Kiedrowski, Mirosław

2017-01-01

Background Thyroid peroxidase (TPO) is essential for physiological function of the thyroid gland. The high prevalence of thyroid peroxidase antibodies (TPOAbs) in patients with breast cancer and their protective role had previously been demonstrated, indicating a link between breast cancer and thyroid autoimmunity. Recently, TPO was shown to be present in breast cancer tissue samples but its antigenicity has not been analyzed. Methods In this study, we investigated TPO expression levels in a series of fifty-six breast cancer samples paired with normal (peri-tumoral) tissue and its antigenic activity using a panel of well-characterized murine anti-human TPOAbs. Results We have shown that TPO transcripts were present in both normal and cancer tissue samples, although the amounts in the latter were reduced. Additionally, we observed that TPO levels are lower in more advanced cancers. TPO protein expression was confirmed in all tissue samples, both normal and cancerous. We also found that the antigenicity of the immunodominant regions (IDRs) in breast TPO resembles that of thyroid TPO, which is crucial for effective interactions with human TPOAbs. Conclusions Expression of TPO in breast cancer together with its antigenic activity may have beneficial effects in TPOAb-positive breast cancer patients. However, further studies are needed to confirm the beneficial role of TPOAbs and to better understand the underlying mechanism. PMID:28575127

A Meta-Analysis of Thyroid-Related Traits Reveals Novel Loci and Gender-Specific Differences in the Regulation of Thyroid Function

PubMed Central

Volpato, Claudia B.; Wilson, Scott G.; Cappola, Anne R.; Bos, Steffan D.; Deelen, Joris; den Heijer, Martin; Freathy, Rachel M.; Lahti, Jari; Liu, Chunyu; Lopez, Lorna M.; Nolte, Ilja M.; O'Connell, Jeffrey R.; Tanaka, Toshiko; Trompet, Stella; Arnold, Alice; Bandinelli, Stefania; Beekman, Marian; Böhringer, Stefan; Brown, Suzanne J.; Buckley, Brendan M.; Camaschella, Clara; de Craen, Anton J. M.; Davies, Gail; de Visser, Marieke C. H.; Ford, Ian; Forsen, Tom; Frayling, Timothy M.; Fugazzola, Laura; Gögele, Martin; Hattersley, Andrew T.; Hermus, Ad R.; Hofman, Albert; Houwing-Duistermaat, Jeanine J.; Jensen, Richard A.; Kajantie, Eero; Kloppenburg, Margreet; Lim, Ee M.; Masciullo, Corrado; Mariotti, Stefano; Minelli, Cosetta; Mitchell, Braxton D.; Nagaraja, Ramaiah; Netea-Maier, Romana T.; Palotie, Aarno; Persani, Luca; Piras, Maria G.; Psaty, Bruce M.; Räikkönen, Katri; Richards, J. Brent; Rivadeneira, Fernando; Sala, Cinzia; Sabra, Mona M.; Sattar, Naveed; Shields, Beverley M.; Soranzo, Nicole; Starr, John M.; Stott, David J.; Sweep, Fred C. G. J.; Usala, Gianluca; van der Klauw, Melanie M.; van Heemst, Diana; van Mullem, Alies; H.Vermeulen, Sita; Visser, W. Edward; Walsh, John P.; Westendorp, Rudi G. J.; Widen, Elisabeth; Zhai, Guangju; Cucca, Francesco; Deary, Ian J.; Eriksson, Johan G.; Ferrucci, Luigi; Fox, Caroline S.; Jukema, J. Wouter; Kiemeney, Lambertus A.; Pramstaller, Peter P.; Schlessinger, David; Shuldiner, Alan R.; Slagboom, Eline P.; Uitterlinden, André G.; Vaidya, Bijay; Visser, Theo J.; Wolffenbuttel, Bruce H. R.; Meulenbelt, Ingrid; Rotter, Jerome I.; Spector, Tim D.; Hicks, Andrew A.; Toniolo, Daniela; Sanna, Serena; Peeters, Robin P.; Naitza, Silvia

2013-01-01

Thyroid hormone is essential for normal metabolism and development, and overt abnormalities in thyroid function lead to common endocrine disorders affecting approximately 10% of individuals over their life span. In addition, even mild alterations in thyroid function are associated with weight changes, atrial fibrillation, osteoporosis, and psychiatric disorders. To identify novel variants underlying thyroid function, we performed a large meta-analysis of genome-wide association studies for serum levels of the highly heritable thyroid function markers TSH and FT4, in up to 26,420 and 17,520 euthyroid subjects, respectively. Here we report 26 independent associations, including several novel loci for TSH (PDE10A, VEGFA, IGFBP5, NFIA, SOX9, PRDM11, FGF7, INSR, ABO, MIR1179, NRG1, MBIP, ITPK1, SASH1, GLIS3) and FT4 (LHX3, FOXE1, AADAT, NETO1/FBXO15, LPCAT2/CAPNS2). Notably, only limited overlap was detected between TSH and FT4 associated signals, in spite of the feedback regulation of their circulating levels by the hypothalamic-pituitary-thyroid axis. Five of the reported loci (PDE8B, PDE10A, MAF/LOC440389, NETO1/FBXO15, and LPCAT2/CAPNS2) show strong gender-specific differences, which offer clues for the known sexual dimorphism in thyroid function and related pathologies. Importantly, the TSH-associated loci contribute not only to variation within the normal range, but also to TSH values outside the reference range, suggesting that they may be involved in thyroid dysfunction. Overall, our findings explain, respectively, 5.64% and 2.30% of total TSH and FT4 trait variance, and they improve the current knowledge of the regulation of hypothalamic-pituitary-thyroid axis function and the consequences of genetic variation for hypo- or hyperthyroidism. PMID:23408906

Unstable Thyroid Function in Older Adults Is Caused by Alterations in Both Thyroid and Pituitary Physiology and Is Associated with Increased Mortality.

PubMed

Mammen, Jennifer S; McGready, John; Ladenson, Paul W; Simonsick, Eleanor M

2017-11-01

Average thyrotropin (TSH) levels are known to be higher in older adults when measured in cross-sectional populations. Possible etiologies include differential survival, neutral aging changes, or increased disease prevalence at older ages. This study aimed to elucidate the mechanisms underlying changing thyroid function during aging, and to determine the association of changes with survival, by analyzing the individual thyroid axis over time. Individual patterns of changing TSH and free thyroxine (fT4) were determined in 640 participants in the Baltimore Longitudinal Study of Aging who had at least three measures of serum TSH and fT4, not on medications, over an average of seven years of follow-up. Participants with changing phenotypes were identified based on quintiles for both slopes. Those with alterations in primary thyroid gland function demonstrated intact negative feedback (rising TSH with declining fT4 or declining TSH with rising fT4). Other participants had a parallel rise or fall of TSH and fT4 levels, consistent with pituitary dysfunction. Predictors of phenotype were analyzed by logistic regression. Differential survival between thyroid aging phenotypes was analyzed using multivariate Cox regression. While the majority of participants at all ages had stable thyroid function, changes were more common among older adults, with 32.3% of those aged >80 years but only 9.5% of those aged <60 years demonstrating thyroid function changes in the highest and lowest quintiles. Regression to the mean accounts for some of the changes, for example increased baseline TSH was associated with a falling TSH pattern (odds ratio = 1.4 [confidence interval 1.1-1.7] per 1 mIU/L). Importantly, changing thyroid function in either the upper or lower quintiles of slope for TSH and fT4 was associated with increased risk of death compared to stable thyroid status (hazard ratio = 5.4 [confidence interval 3.1-9.5]). Changing thyroid hormone function is increasingly common at older ages and is associated with decreased survival. Nonetheless, the tendency for abnormal thyroid function tests to resolve, along with altered pituitary responsiveness underlying some TSH elevations, suggests that an elevated TSH level should be not assumed to represent subclinical hypothyroidism in older adults. Thus, caution is appropriate when determining the need for thyroid hormone supplements in older adults.

Neurotoxicity of Thyroid Disrupting Contaminants

EPA Science Inventory

Thyroid hormones playa critical role in the normal development ofthe mammalian brain. Thyroid disrupting chemicals (TDCs) are environmental contaminants that alter the structure or function ofthe thyroid gland, alter regulatory enzymes associated with thyroid hormone (TH) homeost...

The immune system which adversely alter thyroid functions: a review on the concept of autoimmunity.

PubMed

Mansourian, Azad Reza

2010-08-15

The immune system protect individual from many pathogens exists within our environment and in human body, by destroying them through molecular and cellular mechanism of B and T cells of immune system. Autoimmunity is an adverse relation of immune system against non- foreign substances leaving behind either alters the normal function or destroying the tissue involved. Autoimmunity occur in genetically predispose persons with familial connections. The autoimmunity to the thyroid gland mainly consists of Hashimato thyroiditis and Grave's disease, the two end of spectrum in thyroid function of hypo and hyperactivity, respectively. The thyroid stimulating hormone receptor, thyroglobuline, enzymes of thyroid hormones synthesis are targeted by autoantibodies and cell- mediated reactions. The aim of this review is to explore the studies reported on the autoimmunity to the thyroid gland.

Thyroid and the Heart

PubMed Central

Grais, Ira Martin; Sowers, James R.

2015-01-01

Thyroid hormones modulate every component of the cardiovascular system necessary for normal cardiovascular development and function. When cardiovascular disease is present, thyroid function tests are characteristically indicated to determine if overt thyroid disorders or even subclinical dysfunction exists. As hypothyroidism, hypertension and cardiovascular disease all increase with advancing age monitoring of TSH, the most sensitive test for hypothyroidism, is important in this expanding segment of our population. A better understanding of the impact of thyroid hormonal status on cardiovascular physiology will enable health care providers to make decisions regarding thyroid hormone evaluation and therapy in concert with evaluating and treating hypertension and cardiovascular disease. The goal of this review is to access contemporary understanding of the effects of thyroid hormones on normal cardiovascular function and the potential role of overt and subclinical hypothyroidism and hyperthyroidism in a variety of cardiovascular diseases. PMID:24662620

The role of iodine in human growth and development.

PubMed

Zimmermann, Michael B

2011-08-01

Iodine is an essential component of the hormones produced by the thyroid gland. Thyroid hormones, and therefore iodine, are essential for mammalian life. Iodine deficiency is a major public health problem; globally, it is estimated that two billion individuals have an insufficient iodine intake. Although goiter is the most visible sequelae of iodine deficiency, the major impact of hypothyroidism due to iodine deficiency is impaired neurodevelopment, particularly early in life. In the fetal brain, inadequate thyroid hormone impairs myelination, cell migration, differentiation and maturation. Moderate-to-severe iodine deficiency during pregnancy increases rates of spontaneous abortion, reduces birth weight, and increases infant mortality. Offspring of deficient mothers are at high risk for cognitive disability, with cretinism being the most severe manifestation. It remains unclear if development of the offspring is affected by mild maternal iodine deficiency. Moderate-to-severe iodine deficiency during childhood reduces somatic growth. Correction of mild-to-moderate iodine deficiency in primary school aged children improves cognitive and motor function. Iodine prophylaxis of deficient populations with periodic monitoring is an extremely cost effective approach to reduce the substantial adverse effects of iodine deficiency throughout the life cycle. Copyright © 2011 Elsevier Ltd. All rights reserved.

Biochemical Testing of the Thyroid: TSH is the Best and, Oftentimes, Only Test Needed - A Review for Primary Care.

PubMed

Sheehan, Michael T

2016-06-01

Disorders of thyroid function are common, and screening, diagnosis, and management are often performed by primary care providers. While management of significant biochemical abnormalities is reasonably straight forward, laboratory tests only slightly outside, or even within, the normal range are becoming more difficult to appropriately manage. A large part of this increasing difficulty in appropriate management is caused by patients requesting, and even demanding, certain tests or treatments that may not be indicated. Symptoms of thyroid dysfunction are non-specific and extremely prevalent in the general population. This, along with a growing body of information available to patients via the lay press and internet suggesting that traditional thyroid function testing is not reliable, has fostered some degree of patient mistrust. Increasingly, when a physician informs a patient that their thyroid is not the cause of their symptoms, the patient is dissatisfied and even angry. This review aims to clarify the interpretation of normal and mild abnormalities of thyroid function tests by describing pituitary-thyroid physiology and through an in depth review of, arguably, the three most important biochemical tests of thyroid function: TSH, free T4, and anti-TPO antibodies. It is important for primary care providers to have an understanding of the shortcomings and proper interpretation of these tests to be better able to discuss thyroid function with their patients. © 2016 Marshfield Clinic.

Super-sensitive time-resolved fluoroimmunoassay for thyroid-stimulating hormone utilizing europium(III) nanoparticle labels achieved by protein corona stabilization, short binding time, and serum preprocessing.

PubMed

Näreoja, Tuomas; Rosenholm, Jessica M; Lamminmäki, Urpo; Hänninen, Pekka E

2017-05-01

Thyrotropin or thyroid-stimulating hormone (TSH) is used as a marker for thyroid function. More precise and more sensitive immunoassays are needed to facilitate continuous monitoring of thyroid dysfunctions and to assess the efficacy of the selected therapy and dosage of medication. Moreover, most thyroid diseases are autoimmune diseases making TSH assays very prone to immunoassay interferences due to autoantibodies in the sample matrix. We have developed a super-sensitive TSH immunoassay utilizing nanoparticle labels with a detection limit of 60 nU L -1 in preprocessed serum samples by reducing nonspecific binding. The developed preprocessing step by affinity purification removed interfering compounds and improved the recovery of spiked TSH from serum. The sensitivity enhancement was achieved by stabilization of the protein corona of the nanoparticle bioconjugates and a spot-coated configuration of the active solid-phase that reduced sedimentation of the nanoparticle bioconjugates and their contact time with antibody-coated solid phase, thus making use of the higher association rate of specific binding due to high avidity nanoparticle bioconjugates. Graphical Abstract We were able to decrease the lowest limit of detection and increase sensitivity of TSH immunoassay using Eu(III)-nanoparticles. The improvement was achieved by decreasing binding time of nanoparticle bioconjugates by small capture area and fast circular rotation. Also, we applied a step to stabilize protein corona of the nanoparticles and a serum-preprocessing step with a structurally related antibody.

Incidence of Thyroid-Related Adverse Events in Melanoma Patients Treated With Pembrolizumab

PubMed Central

Jansen, Yanina; Schreuer, Max; Everaert, Hendrik; Velkeniers, Brigitte; Neyns, Bart; Bravenboer, Bert

2016-01-01

Context: Immune checkpoint blockade is associated with endocrine-related adverse events. Thyroid dysfunction during pembrolizumab therapy, an anti-programmed cell death 1 (PD-1) receptor monoclonal antibody, remains to be fully characterized. Objective: To assess the incidence and characteristics of pembrolizumab-associated thyroid dysfunction. Design and Setting: Thyroid function was monitored prospectively in melanoma patients who initiated pembrolizumab within an expanded access program at a referral oncology center. 18Fluorodeoxyglucose uptake on positron emission tomography/computed tomography (18FDG-PET/CT) was reviewed in cases compatible with inflammatory thyroiditis. Patients: Ninety-nine patients with advanced melanoma (age, 26.3–93.6 years; 63.6% females) who received at least one administration of pembrolizumab. Main Outcome Measures: Patient characteristics, thyroid function (TSH, free T4), thyroid autoantibodies, and 18FDG-PET/CT. Results: Eighteen adverse events of thyroid dysfunction were observed in 17 patients. Thyrotoxicosis occurred in 12 patients, of which nine evolved to hypothyroidism. Isolated hypothyroidism was present in six patients. Levothyroxine therapy was required in 10 of 15 hypothyroid patients. Thyroid autoantibodies were elevated during thyroid dysfunction in four of 10 cases. Diffuse increased 18FDG uptake by the thyroid gland was observed in all seven thyrotoxic patients who progressed to hypothyroidism. Conclusions: Thyroid dysfunction is common in melanoma patients treated with pembrolizumab. Hypothyroidism and thyrotoxicosis related to inflammatory thyroiditis are the most frequent presentations. Serial measurements of thyroid function tests are indicated during anti-PD-1 monoclonal antibody therapy. Thyrotoxicosis compatible with inflammatory thyroiditis was associated with diffuse increased 18FDG uptake by the thyroid gland. The prospective role of thyroid autoantibodies should be further investigated, together with the histopathological correlates. PMID:27571185

Role of Nuclear Medicine in the Diagnosis of Benign Thyroid Diseases.

PubMed

Garberoglio, Sara; Testori, Ornella

2016-01-01

A deep understanding of thyroid pathophysiology is the basis for diagnosing and treating benign thyroid diseases with radioactive materials, known as radiopharmaceuticals, which are introduced into the body by injection or orally. After the radiotracer administration, the patient becomes the emitting source, and several devices have been studied to detect and capture these emissions (gamma or beta-negative) and transform them into photons, parametric images, numbers and molecular information. Thyroid scintigraphy is the only technique that allows the assessment of thyroid regional function and, therefore, the detection of areas of autonomously functioning thyroid nodules. Scintigraphy visualizes the distribution of active thyroid tissue and displays the differential accumulation of radionuclides in the investigated cells, thus providing a functional map. Moreover, this technique is a fundamental tool in the clinical and surgical management of thyroid diseases, including: single thyroid nodules with a suppressed thyroid-stimulating hormone level, for which fine-needle aspiration biopsy (FNAB) is used to identify hot nodules; multinodular goiters, especially larger ones, to identify cold or indeterminate areas requiring FNAB and hot areas that do not need cytologic evaluation, and to evaluate mediastinal extension; the diagnosis of ectopic thyroid tissue; subclinical hyperthyroidism to identify occult hyperfunctioning tissue; follicular lesions to identify a functioning cellular adenoma that could be benign, although such nodules are mostly cold on scintigraphy; to distinguish low-uptake from high-uptake thyrotoxicosis, and to determine eligibility for radioiodine therapy. © 2016 S. Karger AG, Basel.

Skin findings in autoimmune and nonautoimmune thyroid disease with respect to thyroid functional status and healthy controls.

PubMed

Takir, Mümtaz; Özlü, Emin; Köstek, Osman; Türkoğlu, Zafer; Mutlu, Hasan Hüseyin; Uzunçakmak, Tuğba Kevser; Akdeniz, Necmettin; Karadağ, Ayşe Serap

2017-06-12

Thyroid disorders are associated with a wide variety of skin disorders that respond to treatment of hormone imbalance in most cases and thus are of vital importance to dermatologists. This study aimed to evaluate skin findings associated with autoimmune and nonautoimmune thyroid disease with respect to thyroid functional status and healthy controls. A total of 300 consecutive patients with either autoimmune (n = 173) or nonautoimmune (n = 127) thyroid disease and 100 healthy control subjects were included in this cross-sectional study. Data on patient demographics, thyroid function tests, and skin findings were recorded for patient and control groups. Compared to control subjects, patients had higher proportions in populations with alopecia (P < 0.001), nail thinning (P = 0.02), brittle nails (P = 0.001), pruritus (P < 0.001), diffuse hyperhidrosis (P = 0.01), flushing (P = 0.001), and xerosis (P < 0.001). Onycholysis (P = 0.02), yellow skin (P = 0.04), periorbital edema (P = 0.03), psoriasis (P = 0.001), and palmoplantar hyperkeratosis (P = 0.007) were significantly more common in patients with autoimmune than nonautoimmune thyroid disease. A significantly higher percentage of patients with autoimmune rather than nonautoimmune thyroid disease had overall skin findings (P = 0.03) among the hyperthyroid patients.Conclusions: Our findings indicate that the presence of skin findings in a majority of thyroid patients significantly differs for certain cutaneous manifestations with respect to controls, autoimmune etiology, and thyroid functional status.

Endogenous subclinical thyroid disorders, physical and cognitive function, depression, and mortality in older individuals.

PubMed

de Jongh, Renate T; Lips, Paul; van Schoor, Natasja M; Rijs, Kelly J; Deeg, Dorly J H; Comijs, Hannie C; Kramer, Mark H H; Vandenbroucke, Jan P; Dekkers, Olaf M

2011-10-01

To what extent endogenous subclinical thyroid disorders contribute to impaired physical and cognitive function, depression, and mortality in older individuals remains a matter of debate. A population-based, prospective cohort of the Longitudinal Aging Study Amsterdam. TSH and, if necessary, thyroxine and triiodothyronine levels were measured in individuals aged 65 years or older. Participants were classified according to clinical categories of thyroid function. Participants with overt thyroid disease or use of thyroid medication were excluded, leaving 1219 participants for analyses. Outcome measures were physical and cognitive function, depressive symptoms (cross-sectional), and mortality (longitudinal) Sixty-four (5.3%) individuals had subclinical hypothyroidism and 34 (2.8%) individuals had subclinical hyperthyroidism. Compared with euthyroidism (n=1121), subclinical hypo-, and hyper-thyroidism were not significantly associated with impairment of physical or cognitive function, or depression. On the contrary, participants with subclinical hypothyroidism did less often report more than one activity limitation (odds ratio 0.44, 95% confidence interval (CI) 0.22-0.86). After a median follow-up of 10.7 years, 601 participants were deceased. Subclinical hypo- and hyper-thyroidism were not associated with increased overall mortality risk (hazard ratio 0.89, 95% CI 0.59-1.35 and 0.69, 95% CI 0.40-1.20 respectively). This study does not support disadvantageous effects of subclinical thyroid disorders on physical or cognitive function, depression, or mortality in an older population.

Persistent Graves' hyperthyroidism despite rapid negative conversion of thyroid-stimulating hormone-binding inhibitory immunoglobulin assay results: a case report.

PubMed

Ohara, Nobumasa; Kaneko, Masanori; Kitazawa, Masaru; Uemura, Yasuyuki; Minagawa, Shinichi; Miyakoshi, Masashi; Kaneko, Kenzo; Kamoi, Kyuzi

2017-02-06

Graves' disease is an autoimmune thyroid disorder characterized by hyperthyroidism, and patients exhibit thyroid-stimulating hormone receptor antibody. The major methods of measuring circulating thyroid-stimulating hormone receptor antibody include the thyroid-stimulating hormone-binding inhibitory immunoglobulin assays. Although the diagnostic accuracy of these assays has been improved, a minority of patients with Graves' disease test negative even on second-generation and third-generation thyroid-stimulating hormone-binding inhibitory immunoglobulins. We report a rare case of a thyroid-stimulating hormone-binding inhibitory immunoglobulin-positive patient with Graves' disease who showed rapid lowering of thyroid-stimulating hormone-binding inhibitory immunoglobulin levels following administration of the anti-thyroid drug thiamazole, but still experienced Graves' hyperthyroidism. A 45-year-old Japanese man presented with severe hyperthyroidism (serum free triiodothyronine >25.0 pg/mL; reference range 1.7 to 3.7 pg/mL) and tested weakly positive for thyroid-stimulating hormone-binding inhibitory immunoglobulins on second-generation tests (2.1 IU/L; reference range <1.0 IU/L). Within 9 months of treatment with oral thiamazole (30 mg/day), his thyroid-stimulating hormone-binding inhibitory immunoglobulin titers had normalized, but he experienced sustained hyperthyroidism for more than 8 years, requiring 15 mg/day of thiamazole to correct. During that period, he tested negative on all first-generation, second-generation, and third-generation thyroid-stimulating hormone-binding inhibitory immunoglobulin assays, but thyroid scintigraphy revealed diffuse and increased uptake, and thyroid ultrasound and color flow Doppler imaging showed typical findings of Graves' hyperthyroidism. The possible explanations for serial changes in the thyroid-stimulating hormone-binding inhibitory immunoglobulin results in our patient include the presence of thyroid-stimulating hormone receptor antibody, which is bioactive but less reactive on thyroid-stimulating hormone-binding inhibitory immunoglobulin assays, or the effect of reduced levels of circulating thyroid-stimulating hormone receptor antibody upon improvement of thyroid autoimmunity with thiamazole treatment. Physicians should keep in mind that patients with Graves' disease may show thyroid-stimulating hormone-binding inhibitory immunoglobulin assay results that do not reflect the severity of Graves' disease or indicate the outcome of the disease, and that active Graves' disease may persist even after negative results on thyroid-stimulating hormone-binding inhibitory immunoglobulin assays. Timely performance of thyroid function tests in combination with sensitive imaging tests, including thyroid ultrasound and scintigraphy, are necessary to evaluate the severity of Graves' disease and treatment efficacy.

[Thyroiditis].

PubMed

Buffet, Camille; Groussin, Lionel

2013-02-01

The diagnosis of thyroiditis encompasses a broad spectrum of thyroid disorders. Analysis of signs and symptoms, biochemical changes, neck ultrasound characteristics and radioactive iodine uptake values allows an accurate diagnosis. Recent studies of the whole genome have helped to identify many susceptibility genes for autoimmune thyroiditis. However, none of these genes contribute to a significant increase in risk of developing this thyroiditis. Clinical awareness of the characteristic presentations of exceptional thyroiditis (acute suppurative thyroiditis, Riedel's thyroiditis) is an important issue. Selenium administration seems to be beneficial for reducing the incidence of thyroiditis. Finally, certain drug-induced thyroiditis remains a therapeutic challenge for the physician.

RISK FACTORS FOR NONREMISSION AND PROGRESSION-FREE SURVIVAL AFTER I-131 THERAPY IN PATIENTS WITH LUNG METASTASIS FROM DIFFERENTIATED THYROID CANCER: A SINGLE-INSTITUTE, RETROSPECTIVE ANALYSIS IN SOUTHERN CHINA.

PubMed

Chen, Pan; Feng, Hui-Juan; Ouyang, Wei; Wu, Ju-Qing; Wang, Jing; Sun, Yun-Gang; Xian, Jia-Lang; Huang, Liu-Hua

2016-09-01

Prognostic factors related to progression-free survival (PFS) have not received much attention in the literature regarding iodine-131 ((131)I) therapy for patients with differentiated thyroid cancer and lung metastases. We sought to explore the factors associated with PFS and nonremission in a group of patients with differentiated thyroid cancer and pulmonary metastases at initial diagnosis and to investigate the impact of (131)I therapy on pulmonary function and peripheral blood counts in the same cohort of patients. The medical records of 1,050 patients with differentiated thyroid cancer treated at the Zhujiang Hospital of Southern Medical University from January 2006 to January 2015 were retrospectively reviewed. Among them, 107 patients fulfilled the inclusion criteria. Multivariate Cox regression analysis indicated that age ≥45 years and (131)I nonavidity were independent risk factors for disease progression. Multivariate logistic regression analysis revealed that pulmonary nodule size ≥1 cm and (131)I nonavidity were the strongest risk factors predicting nonremission. Varying cumulative (131)I dosage had no association with posttreatment pulmonary function or peripheral blood cell counts. Similar to earlier studies, our results confirm that (131)I nonavidity was associated with an increased risk of disease progression and greater odds of nonremission. In addition, patients with differentiated thyroid cancer and lung metastases with pulmonary nodules ≥1 cm had a reduced likelihood of achieving remission. Furthermore, special attention is needed when monitoring patients over 45 years at a higher risk of disease progression. CI = confidence interval DTC = differentiated thyroid cancer (18)F-FDG = fluoro-18 fluorodeoxyglucose FEF = forced expiratory flow FTC = follicular thyroid cancer FVC = forced vital capacity GR = granulocytes Hb = hemoglobin HR = hazard ratio (131)I = iodine-131 LN = lymph node OR = odds ratio OS = overall survival PET/CT = positive positron emission tomography/computed tomography PFS = progression-free survival PT = partial thyroidectomy PTC = papillary thyroid cancer RAI = radioactive iodine RBC = red blood cell Tg = thyroglobulin TgAb = thyroglobulin antibody TSH = thyroid-stimulating hormone TT = total thyroidectomy WBC = white blood cells WBS = whole body scan.

Thyroid functional disease: an under-recognized cardiovascular risk factor in kidney disease patients

PubMed Central

Rhee, Connie M.; Brent, Gregory A.; Kovesdy, Csaba P.; Soldin, Offie P.; Nguyen, Danh; Budoff, Matthew J.; Brunelli, Steven M.; Kalantar-Zadeh, Kamyar

2015-01-01

Thyroid functional disease, and in particular hypothyroidism, is highly prevalent among chronic kidney disease (CKD) and end-stage renal disease (ESRD) patients. In the general population, hypothyroidism is associated with impaired cardiac contractility, endothelial dysfunction, atherosclerosis and possibly higher cardiovascular mortality. It has been hypothesized that hypothyroidism is an under-recognized, modifiable risk factor for the enormous burden of cardiovascular disease and death in CKD and ESRD, but this has been difficult to test due to the challenge of accurate thyroid functional assessment in uremia. Low thyroid hormone levels (i.e. triiodothyronine) have been associated with adverse cardiovascular sequelae in CKD and ESRD patients, but these metrics are confounded by malnutrition, inflammation and comorbid states, and hence may signify nonthyroidal illness (i.e. thyroid functional test derangements associated with underlying ill health in the absence of thyroid pathology). Thyrotropin is considered a sensitive and specific thyroid function measure that may more accurately classify hypothyroidism, but few studies have examined the clinical significance of thyrotropin-defined hypothyroidism in CKD and ESRD. Of even greater uncertainty are the risks and benefits of thyroid hormone replacement, which bear a narrow therapeutic-to-toxic window and are frequently prescribed to CKD and ESRD patients. In this review, we discuss mechanisms by which hypothyroidism adversely affects cardiovascular health; examine the prognostic implications of hypothyroidism, thyroid hormone alterations and exogenous thyroid hormone replacement in CKD and ESRD; and identify areas of uncertainty related to the interplay between hypothyroidism, cardiovascular disease and kidney disease requiring further investigation. PMID:24574542

Marine-Lenhart syndrome with papillary thyroid carcinoma.

PubMed

Atmaca, Hulusi; Çolak, Ramis; Yazici, Zihni Acar; Kefeli, Mehmet; Tosun, Fevziye Canbaz

2015-04-01

Graves' disease with accompanying functioning nodules is known as Marine-Lenhart syndrome. Autonomously functioning thyroid nodules (AFTNs) also within Graves' thyroid tissue are almost always bening in nature. A 45-year-old man developed hyperthyroidism due to the coexistence of Graves' disease and AFTN. Total thyroidectomy was performed. The hyperfunctioning nodule with centrally hypoactive foci detected by technetium-99m thyroid scanning was histologically diagnosed as papillary thyroid carcinoma that was 2.5 cm in diameter. We report the presence of papillary thyroid carcinoma within AFTN in patients with Marine-Lenhart syndrome, which has not been reported so far.

Severe Hypothyroidism due to the Loss of Therapeutic Efficacy of l-Thyroxine in a Patient with Esophageal Complication Associated with Systemic Sclerosis.

PubMed

Lobasso, Antonio; Nappi, Liliana; Barbieri, Letizia; Peirce, Carmela; Ippolito, Serena; Arpaia, Debora; Rossi, Francesca Wanda; de Paulis, Amato; Biondi, Bernadette

2017-01-01

Thyroid function abnormalities and thyroid autoantibodies have been frequently described in patients with systemic autoimmune diseases as systemic sclerosis (SSc). Serum TSH levels are higher in SSc patients with more severe skin diseases and a worse modified Rodnan skin score. Asymptomatic esophageal involvement due to SSc has never been described as a cause of severe hypothyroidism due to l-thyroxine (l-T4) malabsorption in patients with Hashimoto's thyroiditis (HT) and SSc. Here, we report a case of a 56-year-old female affected by both SSc and HT who developed severe hypothyroidism due to the loss of therapeutic efficacy of l-T4. Therapeutic failure resulted from the altered l-T4 absorption because of SSc esophageal complications. Clinical findings improved after the administration of oral liquid l-T4. Thyroid function completely normalized with a full clinical recovery, the disappearance of the pericardial effusion and the improvement of the pulmonary pressure. A recognition of a poor absorption is crucial in patients with hypothyroidism and SSc to reduce the risk of the subsequent adverse events. This case suggests the importance of clinical and laboratory surveillance in patients with SSc and HT because the systemic complications of these dysfunctions may worsen the prognosis of hypothyroid SSc/HT patients.

Low thyroid function is not associated with an accelerated deterioration in renal function.

PubMed

Meuwese, Christiaan L; van Diepen, Merel; Cappola, Anne R; Sarnak, Mark J; Shlipak, Michael G; Bauer, Douglas C; Fried, Linda P; Iacoviello, Massimo; Vaes, Bert; Degryse, Jean; Khaw, Kay-Tee; Luben, Robert N; Åsvold, Bjørn O; Bjøro, Trine; Vatten, Lars J; de Craen, Anton J M; Trompet, Stella; Iervasi, Giorgio; Molinaro, Sabrina; Ceresini, Graziano; Ferrucci, Luigi; Dullaart, Robin P F; Bakker, Stephan J L; Jukema, J Wouter; Kearney, Patricia M; Stott, David J; Peeters, Robin P; Franco, Oscar H; Völzke, Henry; Walsh, John P; Bremner, Alexandra; Sgarbi, José A; Maciel, Rui M B; Imaizumi, Misa; Ohishi, Waka; Dekker, Friedo W; Rodondi, Nicolas; Gussekloo, Jacobijn; den Elzen, Wendy P J

2018-04-18

Chronic kidney disease (CKD) is frequently accompanied by thyroid hormone dysfunction. It is currently unclear whether these alterations are the cause or consequence of CKD. This study aimed at studying the effect of thyroid hormone alterations on renal function in cross-sectional and longitudinal analyses in individuals from all adult age groups. Individual participant data (IPD) from 16 independent cohorts having measured thyroid stimulating hormone, free thyroxine levels and creatinine levels were included. Thyroid hormone status was defined using clinical cut-off values. Estimated glomerular filtration rates (eGFR) were calculated by means of the four-variable Modification of Diet in Renal Disease (MDRD) formula. For this IPD meta-analysis, eGFR at baseline and eGFR change during follow-up were computed by fitting linear regression models and linear mixed models in each cohort separately. Effect estimates were pooled using random effects models. A total of 72 856 individuals from 16 different cohorts were included. At baseline, individuals with overt hypothyroidism (n = 704) and subclinical hypothyroidism (n = 3356) had a average (95% confidence interval) -4.07 (-6.37 to -1.78) and -2.40 (-3.78 to -1.02) mL/min/1.73 m2 lower eGFR as compared with euthyroid subjects (n = 66 542). In (subclinical) hyperthyroid subjects (n = 2254), average eGFR was 3.01 (1.50-4.52) mL/min/1.73 m2 higher. During 329 713 patient years of follow-up, eGFR did not decline more rapidly in individuals with low thyroid function compared with individuals with normal thyroid function. Low thyroid function is not associated with a deterioration of renal function. The cross-sectional association may be explained by renal dysfunction causing thyroid hormone alterations.

Thyroid hormones and thyroid disease in relation to perchlorate dose and residence near a superfund site.

PubMed

Gold, Ellen B; Blount, Benjamin C; O'Neill Rasor, Marianne; Lee, Jennifer S; Alwis, Udeni; Srivastav, Anup; Kim, Kyoungmi

2013-07-01

Perchlorate is a widely occurring contaminant, which can competitively inhibit iodide uptake and thus thyroid hormone production. The health effects of chronic low dose perchlorate exposure are largely unknown. In a community-based study, we compared thyroid function and disease in women with differing likelihoods of prior and current perchlorate exposure. Residential blocks were randomly selected from areas: (1) with potential perchlorate exposure via drinking water; (2) with potential exposure to environmental contaminants; and (3) neighboring but without such exposures. Eligibility included having lived in the area for ≥6 months and aged 20-50 years during 1988-1996 (during documented drinking water well contamination). We interviewed 814 women and collected blood samples (assayed for thyroid stimulating hormone and free thyroxine) from 431 interviewed women. Daily urine samples were assayed for perchlorate and iodide for 178 premenopausal women with blood samples. We performed multivariable regression analyses comparing thyroid function and disease by residential area and by urinary perchlorate dose adjusted for urinary iodide levels. Residential location and current perchlorate dose were not associated with thyroid function or disease. No persistent effect of perchlorate on thyroid function or disease was found several years after contaminated wells were capped.

STRATEGIES TO REDUCE OR REPLACE THE USE OF ANIMALS IN THE ENDOCRINE SCREENING AND TESTING PROGRAM.

EPA Science Inventory

Abstract: The US Environmental Protection Agency (EPA) is developing a screening and testing program for endocrine disrupting chemicals (EDCs) to detect alterations of hypothalamic-pituitary-gonadal (HPG) function, estrogen, androgen and thyroid hormone synthesis and androgen (AR...

Papillary thyroid carcinoma in an autonomous hyperfunctioning thyroid nodule: case report and review of the literature.

PubMed

Tfayli, Hala M; Teot, Lisa A; Indyk, Justin A; Witchel, Selma Feldman

2010-09-01

Whereas thyroid nodules are less common among children than among adults, the anxiety generated by the finding of a thyroid nodule is high because 20% of nodules found in children contain thyroid cancer. Discovery of a nodule in the context of hyperthyroidism is usually comforting due to the presumption that the nodule represents a benign toxic adenoma. An 11-year-old girl presented with heavy menses, fatigue, and a right thyroid mass. Laboratory evaluation revealed elevated triiodothyronine and undetectable thyroid-stimulating hormone. Thyroid ultrasonography revealed a 3.5 cm nonhomogenous nodule, and scintigraphy was consistent with an autonomous hyper-functioning nodule. Fine-needle aspiration biopsy could not rule out malignancy, and patient underwent right hemithyroidectomy and isthmusectomy. Pathology was consistent with papillary thyroid carcinoma. We report the discovery of papillary thyroid carcinoma in an autonomously hyperfunctioning nodule in an 11-year-old girl. Detection of an autonomously functioning thyroid nodule in children and adolescents does not exclude the possibility of thyroid carcinoma and warrants careful evaluation and appropriate therapy.

Papillary Thyroid Carcinoma in an Autonomous Hyperfunctioning Thyroid Nodule: Case Report and Review of the Literature

PubMed Central

Tfayli, Hala M.; Teot, Lisa A.; Indyk, Justin A.

2010-01-01

Background Whereas thyroid nodules are less common among children than among adults, the anxiety generated by the finding of a thyroid nodule is high because 20% of nodules found in children contain thyroid cancer. Discovery of a nodule in the context of hyperthyroidism is usually comforting due to the presumption that the nodule represents a benign toxic adenoma. Summary An 11-year-old girl presented with heavy menses, fatigue, and a right thyroid mass. Laboratory evaluation revealed elevated triiodothyronine and undetectable thyroid-stimulating hormone. Thyroid ultrasonography revealed a 3.5 cm nonhomogenous nodule, and scintigraphy was consistent with an autonomous hyper-functioning nodule. Fine-needle aspiration biopsy could not rule out malignancy, and patient underwent right hemithyroidectomy and isthmusectomy. Pathology was consistent with papillary thyroid carcinoma. Conclusions We report the discovery of papillary thyroid carcinoma in an autonomously hyperfunctioning nodule in an 11-year-old girl. Detection of an autonomously functioning thyroid nodule in children and adolescents does not exclude the possibility of thyroid carcinoma and warrants careful evaluation and appropriate therapy. PMID:20718686

Factors associated with serum thyroglobulin levels in a population living in Belarus

PubMed Central

Cahoon, Elizabeth K; Rozhko, Alexander; Hatch, Maureen; Polyanskaya, Olga; Ostroumova, Evgenia; Tang, Min; Nadirov, Eldar; Yauseyenka, Vasilina; Savasteeva, Irina; McConnell, Robert J; Pfeiffer, Ruth M; Brenner, Alina V

2013-01-01

SUMMARY Objective Serum thyroglobulin (Tg) has been associated with a number of thyroid disorders and has been proposed as an indicator of iodine deficiency in a population. However, few studies have addressed the epidemiology of Tg in a population-based setting or in the context of exposure to radioactive iodine-131 (I-131). Our objective was to evaluate baseline levels of Tg in relation to socio-demographic characteristics, iodine status, and thyroid function for individuals exposed to I-131. Design A population-based cohort assembled in Belarus following the Chornobyl accident provided demographic factors, clinical data, and physiological measurements. Participants Our analytic sample included 10,344 subjects of whom 7,890 had no thyroid disease and 2,454 had evidence of structural or functional thyroid abnormality. Measurements Standardized assays were used to measure serum Tg, urinary iodine, TSH, and antibodies to Tg and thyroid peroxidase. Ultrasound was used to assess the presence of nodules and estimate thyroid volume. Results In the fully adjusted model, percent change in Tg was significantly increased among females, smokers, and subjects of older age and Tg increased with decreasing urinary iodine concentration, increasing serum TSH and increasing thyroid volume (p-values for trend < 0.0001), and presence of thyroid nodules (p < 0.05). We found a complex interaction between region of residence, rural/urban living, presence/absence of thyroid abnormalities, and serum Tg (p < 0.0001). Conclusions In residents of Belarus, serum Tg is significantly related to presence of thyroid abnormalities as well as indicators of thyroid function and iodine deficiency and, therefore, could be used to characterize the iodine status and thyroid function of individuals in the context of epidemiological study. PMID:23190420

Potential Influence of Selenium, Copper, Zinc and Cadmium on L-Thyroxine Substitution in Patients with Hashimoto Thyroiditis and Hypothyroidism.

PubMed

Rasic-Milutinovic, Z; Jovanovic, D; Bogdanovic, G; Trifunovic, J; Mutic, J

2017-02-01

Background: Besides genetic factors, it is known that some trace elements, as Selenium, Copper, and Zinc are essential for thyroid gland fuction and thyroid hormone metabolism. Moreover, there were some metals effect that suggested patterns associated with overt thyroid disease. Aim of study: Hashimoto thyroiditis (HT), chronic autoimune inflamation of thyroid gland with cosequtive hipothyroidism, is common disease in Serbia, and we thought it is worthwile to explore potential effects of essential and toxic metals and metalloides on thyroid function and ability to restore euthyroid status of them. Results: This cross-sectional, case-control, study investigated the status of essential elements (Selenium,Copper,and Zinc) and toxic metals and metalloides (Al, Cr, Mn, Co, As, Cd, Sb, Ba, Be, Pb and Ni) from the blood of 22 female, patients with Hashimoto thyroiditis and overt hypothyroidism, and compared it with those of 55 female healthy persons. We tried to establish the presence of any correlation between previous mentioned elements and thyroid function in hypothyroid patients and healthy participants. Conclusions: The results of our study suggested that the blood concentration of essential trace elements, especially the ratio of Copper, and Selenium may influence directly thyroid function in patients with HT and overt hypothyroidism.Thus, our findings may have implication to life-long substitution therapy in terms of l-thyroxine dose reduction. Furthermore, for the first time, our study shown potential toxic effect of Cadmium on thyroid function in HT patients, which may implicate the dose of l-thyroxine substitution. © Georg Thieme Verlag KG Stuttgart · New York.

The value of thyroid shielding in intraoral radiography

PubMed Central

Hazenoot, Bart; Sanderink, Gerard C H; Berkhout, W Erwin R

2016-01-01

Objectives: To evaluate the utility of the application of a thyroid shield in intraoral radiography when using rectangular collimation. Methods: Experimental data were obtained by measuring the absorbed dose at the position of the thyroid gland in a RANDO® (The Phantom Laboratory, Salem, NY) male phantom with a dosemeter. Four protocols were tested: round collimation and rectangular collimation, both with and without thyroid shield. Five exposure positions were deployed: upper incisor (Isup), upper canine (Csup), upper premolar (Psup), upper molar (Msup) and posterior bitewing (BW). Exposures were made with 70 kV and 7 mA and were repeated 10 times. The exposure times were as recommended for the exposure positions for the respective collimator type by the manufacturer for digital imaging. The data were statistically analyzed with a three-way ANOVA test. Significance was set at p < 0.01. Results: The ANOVA test revealed that the differences between mean doses of all protocols and geometries were statistically significant, p < 0.001. For the Isup, thyroid dose levels were comparable with both collimators at a level indicating primary beam exposure. Thyroid shield reduced this dose with circa 75%. For the Csup position, round collimation also revealed primary beam exposure, and thyroid shield yield was 70%. In Csup with rectangular collimation, the thyroid dose was reduced with a factor 4 compared with round collimation and thyroid shield yielded an additional 42% dose reduction. The thyroid dose levels for the Csup, Psup, Msup and BW exposures were lower with rectangular collimation without thyroid shield than with round collimation with thyroid shield. With rectangular collimation, the thyroid shield in Psup, Msup and BW reduced the dose 10% or less, where dose levels were already low, implying no clinical significance. Conclusions: For the exposures in the upper anterior region, thyroid shield results in an important dose reduction for the thyroid. For the other exposures, thyroid shield augments little to the reduction achieved by rectangular collimation. The use of thyroid shield is to be advised, when performing upper anterior radiography. PMID:27008105

Thyroid Emergencies

PubMed Central

Leung, Angela M

2017-01-01

Myxedema coma and thyroid storm are thyroid emergencies associated with increased mortality. Prompt recognition of these states—which represent the severe, life-threatening conditions of extremely reduced or elevated circulating thyroid hormone concentrations, respectively—is necessary to initiate treatment. Management of myxedema coma and thyroid storm requires both medical and supportive therapies and should be treated in an intensive care unit setting. PMID:27598067

Soy isoflavones inducing overt hypothyroidism in a patient with chronic lymphocytic thyroiditis: a case report.

PubMed

Nakamura, Yuya; Ohsawa, Isao; Goto, Yoshikazu; Tsuji, Mayumi; Oguchi, Tatsunori; Sato, Naoki; Kiuchi, Yuji; Fukumura, Motonori; Inagaki, Masahiro; Gotoh, Hiromichi

2017-09-05

Many people have thyroid conditions that make them susceptible to hypothyroidism. If the foods they eat may interfere with the production of thyroid hormone, which can lead to development of serious hypothyroidism. The danger of health drinks should always be noted. A 72-year-old Japanese woman was previously diagnosed with chronic lymphocytic thyroiditis caused by a goiter and had an elevated thyroid-stimulating hormone level (6.56 μIU/ml), a high anti-thyroid peroxidase antibody level (>600 IU/ml), and a high antithyroglobulin level (> 4000 IU/ml) but normal levels of free triiodothyronine (3.08 pg/ml) and thyroxine (1.18 ng/ml). She presented to our hospital with sudden-onset general malaise, edema, and hoarseness with an elevated thyroid-stimulating hormone (373.3 μIU/ml) level and very low triiodothyronine (< 0.26 pg/ml) and thyroxine (0.10 ng/ml) levels. It was determined that for 6 months she had been consuming a processed, solved health drink ("barley young leaf") in amounts of 9 g/day, which included soybean and kale powder extract. Hypothyroidism might be affected by ingredients of health drinks. She discontinued consumption of the health drink immediately and began taking 12.5 μg of levothyroxine. The amount of levothyroxine was gradually increased every 3 days up to 100 μg. At day 61, her thyroid-stimulating hormone level had decreased (6.12 μIU/ml), her free triiodothyronine (2.69 pg/ml) and thyroxine (1.56 ng/ml) levels had increased, and her general condition was improved. Among risky foods lowering thyroid function, some experimental studies have revealed that isoflavones reduce thyroid function. Therefore, we measured the presence of isoflavones in the patient's frozen serum with thin-layer chromatography. After she discontinued consumption of the health drink, two components quickly disappeared, and the other three components gradually decreased. On the basis of developing solvent composition and a positive ferric chloride reaction in thin-layer chromatography experiment, the five ingredients that disappeared or decreased were highly suspected to be soy isoflavones. This case emphasizes that consuming health drinks that include soy isoflavone powder extracts can lead to severe hypothyroidism.

Submandibular ectopic thyroid with normally located thyroid gland.

PubMed

Yılmaz, Mahmut Sinan; Aytürk, Semra; Güven, Mehmet; Dilek, Fatma Hüsniye

2014-01-01

Ectopic thyroid is a rare developmental anomaly of the thyroid gland which is defined as the presence of thyroid tissue at a site other than the pretracheal area. Nearly 1 to 3% of all ectopic thyroids are located in the lateral neck. Simultaneous submandibular ectopic thyroid tissue presenting with a functional orthotopic thyroid gland is extremely rare. In this article, we report a 37-year-old female case admitted to our clinic with a complaint of swollen neck in whom ultrasonography revealed submandibular ectopic thyroid tissue presenting with an orthotopic thyroid gland.

Increased incidence of thyroid dysfunction and autoimmunity in patients with vernal keratoconjunctivitis.

PubMed

Stagi, Stefano; Pucci, Neri; Di Grande, Laura; de Libero, Cinzia; Caputo, Roberto; Pantano, Stefano; Mattei, Ivan; Mori, Francesca; de Martino, Maurizio; Novembre, Elio

2014-01-01

Hormones may play a role in the pathophysiology of vernal keratoconjunctivitis (VKC). An increased incidence of thyroid autoantibodies was recently observed in VKC, although there were no data on thyroid function. Two hundred and eighty-eight patients (202 males, 86 females; range 5.5 to 16.9 years) with VKC were evaluated and compared with 188 normal age- and sex-matched subjects. In all subjects, serum concentrations of free T4, TSH, thyroperoxidase, thyroglobulin, and TSHr autoantibodies were evaluated. In VKC, the family history of thyroid diseases showed no significant differences compared to the controls (9.4 versus 8.6%), whereas the family history of autoimmune diseases was significantly higher (13.2% versus 6.3%; P<0.05). Subclinical hypothyroidism was diagnosed in 6.6% (versus 1.6% of the controls; P<0.05) and overt hypothyroidism in 0.7% (versus 0.0% of the controls; P = NS). Finally, 5.2% of patients were positive for thyroid autoantibodies, which were significantly higher with respect to the controls (0.5%, P<0.05). In the patients positive for thyroid autoantibodies, 80% showed a sonography pattern that suggested autoimmune thyroiditis. Thyroid function and autoimmunity abnormalities are frequently present in children with VKC. Children with VKC should be screened for thyroid function and evaluated for thyroid autoimmunity.

Increased Incidence of Thyroid Dysfunction and Autoimmunity in Patients with Vernal Keratoconjunctivitis

PubMed Central

Stagi, Stefano; Pucci, Neri; Di Grande, Laura; de Libero, Cinzia; Caputo, Roberto; Pantano, Stefano; Mattei, Ivan; Mori, Francesca; de Martino, Maurizio; Novembre, Elio

2014-01-01

Hormones may play a role in the pathophysiology of vernal keratoconjunctivitis (VKC). An increased incidence of thyroid autoantibodies was recently observed in VKC, although there were no data on thyroid function. Two hundred and eighty-eight patients (202 males, 86 females; range 5.5 to 16.9 years) with VKC were evaluated and compared with 188 normal age- and sex-matched subjects. In all subjects, serum concentrations of free T4, TSH, thyroperoxidase, thyroglobulin, and TSHr autoantibodies were evaluated. In VKC, the family history of thyroid diseases showed no significant differences compared to the controls (9.4 versus 8.6%), whereas the family history of autoimmune diseases was significantly higher (13.2% versus 6.3%; P<0.05). Subclinical hypothyroidism was diagnosed in 6.6% (versus 1.6% of the controls; P<0.05) and overt hypothyroidism in 0.7% (versus 0.0% of the controls; P = NS). Finally, 5.2% of patients were positive for thyroid autoantibodies, which were significantly higher with respect to the controls (0.5%, P<0.05). In the patients positive for thyroid autoantibodies, 80% showed a sonography pattern that suggested autoimmune thyroiditis. Thyroid function and autoimmunity abnormalities are frequently present in children with VKC. Children with VKC should be screened for thyroid function and evaluated for thyroid autoimmunity. PMID:25140177

An unusual case of hypopituitarism and transient thyrotoxicosis following asymptomatic pituitary apoplexy.

PubMed

Yoshida, Masanori; Murakami, Miho; Ueda, Harumi; Miyata, Misaki; Takahashi, Norio; Oiso, Yutaka

2014-01-01

Although pituitary function is often impaired in pituitary apoplexy, the development of thyrotoxicosis is rare. We describe an unusual case of hypopituitarism due to pituitary apoplexy coexisting with transient hyperthyroidism. A 74-year-old woman presented with severe fatigue, palpitation, appetite loss, hypotension, and hyponatremia. Endocrine studies showed hyperthyroidism and anterior pituitary hormone deficiencies. A magnetic resonance imaging suggested recent-onset pituitary apoplexy in a pituitary tumor, although the patient had no apoplectic symptoms such as headache and visual disturbance. Thyrotoxicosis and adrenal insufficiency worsened her general condition. Glucocorticoid supplementation improved her clinical symptoms and hyponatremia. Serum anti-thyrotropin receptor and thyroid-stimulating antibody titers were negative, and her thyroid function was spontaneously normalized without antithyroid medication, suggesting painless thyroiditis. Thereafter, her thyroid function decreased because of central hypothyroidism and 75 µg of levothyroxine was needed to maintain thyroid function at the euthyroid stage. The pituitary mass was surgically removed and an old hematoma was detected in the specimen. Considering that painless thyroiditis develops as a result of an autoimmune process, an immune rebound mechanism due to adrenal insufficiency probably caused painless thyroiditis. Although the most common type of thyroid disorder in pituitary apoplexy is central hypothyroidism, thyrotoxicosis caused by painless thyroiditis should be considered even if the patient has pituitary deficiencies. Because thyrotoxicosis with adrenal insufficiency poses a high risk for a life-threatening adrenal crisis, prompt diagnosis and treatment are critical.

Successful treatment of thyroid storm presenting as recurrent cardiac arrest and subsequent multiorgan failure by continuous renal replacement therapy.

PubMed

Park, Han Soo; Kwon, Su Kyoung; Kim, Ye Na

2017-01-01

Thyroid storm is a rare and potentially life-threatening medical emergency. We experienced a case of thyroid storm associated with sepsis caused by pneumonia, which had a catastrophic course including recurrent cardiac arrest and subsequent multiple organ failure (MOF). A 22-year-old female patient with a 10-year history of Graves' disease was transferred to our emergency department (ED). She had a cardiac arrest at her home and a second cardiac arrest at the ED. Her heart recovered after 20 min of cardiac resuscitation. She was diagnosed with thyroid storm associated with hyperthyroidism complicated by pneumonia and sepsis. Although full conventional medical treatment was given, she had progressive MOF and hemodynamic instability consisting of hyperthermia, tachycardia and hypotension. Because of hepatic and renal failure with refractory hypotension, we reduced the patient's dose of beta-blocker and antithyroid drug, and she was started on continuous veno-venous renal replacement therapy (CRRT) with intravenous albumin and plasma supplementation. Subsequently, her body temperature and pulse rate began to stabilize within 1 h, and her blood pressure reached 120/60 mmHg after 6 h. We discontinued antithyroid drug 3 days after admission because of aggravated hyperbilirubinemia. The patient exhibited progressive improvement in thyroid function even after cessation of antithyroid drug, and she successfully recovered from thyroid storm and MOF. This is the first case of thyroid storm successfully treated by CRRT in a patient considered unfit for antithyroid drug treatment. The presenting manifestations of thyroid storm vary and can include cardiac arrest with multiorgan failure in rare cases.In some patients with thyroid storm, especially those with severe complications, conventional medical treatment may be ineffective or inappropriate.During thyroid storm, the initiation of CRRT can immediately lower body temperature and subsequently stabilize vital signs.Early initiation of CRRT can be life-saving in patients with thyroid storm complicated by MOF, even when used in combination with suboptimal medical treatment.

Thyroid hormone concentrations in captive and free-ranging West Indian manatees (Trichechus manatus).

PubMed

Ortiz, R M; MacKenzie, D S; Worthy, G A

2000-12-01

Because thyroid hormones play a critical role in the regulation of metabolism, the low metabolic rates reported for manatees suggest that thyroid hormone concentrations in these animals may also be reduced. However, thyroid hormone concentrations have yet to be examined in manatees. The effects of captivity, diet and water salinity on plasma total triiodothyronine (tT(3)), total thyroxine (tT(4)) and free thyroxine (fT(4)) concentrations were assessed in adult West Indian manatees (Trichechus manatus). Free-ranging manatees exhibited significantly greater tT(4) and fT(4) concentrations than captive adults, regardless of diet, indicating that some aspect of a captive existence results in reduced T(4) concentrations. To determine whether this reduction might be related to feeding, captive adults fed on a mixed vegetable diet were switched to a strictly sea grass diet, resulting in decreased food consumption and a decrease in body mass. However, tT(4) and fT(4) concentrations were significantly elevated over initial values for 19 days. This may indicate that during periods of reduced food consumption manatees activate thyroid-hormone-promoted lipolysis to meet water and energetic requirements. Alterations in water salinity for captive animals did not induce significant changes in thyroid hormone concentrations. In spite of lower metabolic rates, thyroid hormone concentrations in captive manatees were comparable with those for other terrestrial and marine mammals, suggesting that the low metabolic rate in manatees is not attributable to reduced circulating thyroid hormone concentrations.

Glomerular filtration rate is associated with free triiodothyronine in euthyroid subjects: Comparison between various equations to estimate renal function and creatinine clearance.

PubMed

Anderson, Josephine L C; Gruppen, Eke G; van Tienhoven-Wind, Lynnda; Eisenga, Michele F; de Vries, Hanne; Gansevoort, Ron T; Bakker, Stephan J L; Dullaart, Robin P F

2018-02-01

Effects of variations in thyroid function within the euthyroid range on renal function are unclear. Cystatin C-based equations to estimate glomerular filtration rate (GFR) are currently advocated for mortality and renal risk prediction. However, the applicability of cystatin C-based equations is discouraged in patients with overt thyroid dysfunction, since serum cystatin C and creatinine levels are oppositely affected by thyroid dysfunction. Here, we compared relationships of thyroid stimulating hormone (TSH), free thyroxine (FT4) and free triiodothyronine (FT3) with various measures of kidney function in euthyroid subjects. Relationships of eGFR, based on creatinine (eGFRcrea), cystatin C (eGFRcysC), creatinine+cystatin C combined (eGFRcrea-cysC) and creatinine clearance (CrCl) with TSH, FT4 and FT3 were determined in 2180 euthyroid subjects (TSH, FT4 and FT3 all within the reference range; anti-thyroid peroxidase autoantibodies negative) who did not use thyroid hormones, anti-thyroid drugs, amiodarone or lithium carbonate. In multivariable models including TSH, FT3 and FT4 together, eGFRcrea, eGFRcysC and eGFRcrea-cysC and CrCl were all positively related to FT3 (P≤0.001), translating into a 2.61 to 2.83mL/min/1.73m 2 increase in eGFR measures and a 3.92mL/min increase in CrCl per 1pmol/L increment in FT3. These relationships with FT3 remained taking account of relevant covariates. In euthyroid subjects renal function is associated with thyroid function status, especially by serum FT3, irrespective of the eGFR equation applied. In the euthyroid state, cystatin C-based eGFR equations are appropriate to assess the relationship of renal function with variation in thyroid function status. Copyright © 2017 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Thyroid hormone and cerebellar development.

PubMed

Anderson, Grant W

2008-01-01

Thyroid hormone (TH) plays a key role in mammalian brain development. The developing brain is sensitive to both TH deficiency and excess. Brain development in the absence of TH results in motor skill deficiencies and reduced intellectual development. These functional abnormalities can be attributed to maldevelopment of specific cell types and regions of the brain including the cerebellum. TH functions at the molecular level by regulating gene transcription. Therefore, understanding how TH regulates cerebellar development requires identification of TH-regulated gene targets and the cells expressing these genes. Additionally, the process of TH-dependent regulation of gene expression is tightly controlled by mechanisms including regulation of TH transport, TH metabolism, toxicologic inhibition of TH signaling, and control of the nuclear TH response apparatus. This review will describe the functional, cellular, and molecular effects of TH deficit in the developing cerebellum and emphasize the most recent findings regarding TH action in this important brain region.

Inhibition of Tumorigenesis by the Thyroid Hormone Receptor β in Xenograft Models

PubMed Central

Kim, Won Gu; Zhao, Li; Kim, Dong Wook; Willingham, Mark C.

2014-01-01

Background: Previous studies showed a close association between several types of human cancers and somatic mutations of thyroid hormone receptor β (TRβ) and reduced expression of TRβ due to epigenetic inactivation and/or deletion of the THRB gene. These observations suggest that TRβ could act as a tumor suppressor in carcinogenesis. However, the mechanisms by which TRβ could function to inhibit tumorigenesis are less well understood. Methods: We used the human follicular thyroid cancer cell lines (FTC-133 and FTC-236 cells) to elucidate how functional expression of the THRB gene could affect tumorigenesis. We stably expressed the THRB gene in FTC cells and evaluated the effects of the expressed TRβ on cancer cell proliferation, migration, and tumor growth in cell-based studies and xenograft models. Results: Expression of TRβ in FTC-133 cells, as compared with control FTC cells without TRβ, reduced cancer cell proliferation and impeded migration of tumor cells through inhibition of the AKT-mTOR-p70 S6K pathway. TRβ expression in FTC-133 and FTC-236 led to less tumor growth in xenograft models. Importantly, new vessel formation was significantly suppressed in tumors induced by FTC cells expressing TRβ compared with control FTC cells without TRβ. The decrease in vessel formation was mediated by the downregulation of vascular endothelial growth factor in FTC cells expressing TRβ. Conclusions: These findings indicate that TRβ acts as a tumor suppressor through downregulation of the AKT-mTOR-p70 S6K pathway and decreased vascular endothelial growth factor expression in FTC cells. The present results raise the possibility that TRβ could be considered as a potential therapeutic target for thyroid cancer. PMID:23731250

Quantitative thyroid scintigraphy in greyhounds suspected of primary hypothyroidism.

PubMed

Pinilla, Manuel; Shiel, Robert E; Brennan, Sheila F; McAllister, Hester; Mooney, Carmel T

2009-01-01

The existence of hypothyroidism in greyhounds remains controversial and its investigation is complicated by the low circulating thyroid hormone concentrations typically found in healthy dogs of this breed. Quantitative measurement of thyroidal technetium-99m pertechnetate ((99m)TcO4-) uptake is known to be useful in assessing thyroid function in other breeds. The aim of this study was to evaluate thyroid scintigraphy as a method of assessing thyroid function in greyhounds suspected of primary hypothyroidism. Twenty greyhounds (eight females, 12 males) were studied. Thirteen had bald thigh syndrome and seven poor performance and low total T4. Total T4 concentrations were decreased in 18 (90%), and free T4 in two (10%) dogs. All canine thyroid stimulating hormone concentrations were within the reference interval. Thyroidal (99m)TcO4- uptake values (mean +/- SD, 0.76 +/- 0.26%) were within the reference limits published for euthyroid dogs (0.39-1.86%) making hypothyroidism highly unlikely. There were no significant differences (P < 0.05) when comparing data between dogs with bald thigh syndrome (13 dogs) and the remaining dogs (seven dogs). Seventeen (85%) dogs had higher uptake in the left thyroid gland than in the right that might reflect an anatomic feature of the greyhound breed. Calculation of percent thyroidal uptake of (99m)TcO4- is more accurate than thyroid: salivary gland ratios because of high variability in salivary gland uptake. Percent thyroidal uptake of (99m)TcO4- should be used when assessing thyroid function scintigraphically in the greyhound breed.

Thyroid autoimmunity and function among Ugandan children and adolescents with type-1 diabetes mellitus.

PubMed

Muhame, Rugambwa Michael; Mworozi, Edison Arwanire; McAssey, Karen; Lubega, Irene

2014-01-01

Up to 30% of type-1 diabetes mellitus (T1DM) patients have co-existent thyroid autoimmunity with up to 50% of them having associated thyroid dysfunction. Routine screening for thyroid autoimmunity and dysfunction is recommended in all T1DM patients. However, this was not currently practiced in Ugandan paediatric diabetes clinics. There was also paucity of data regarding thyroid autoimmunity and dysfunction in African children and adolescents with diabetes mellitus. The objective of this study was to quantify the magnitude of thyroid autoimmunity and dysfunction in Ugandan children with TIDM. This was a cross sectional descriptive study to determine the prevalence of thyroid autoantibodies and describe thyroid function among children and adolescents aged 1-19 years with diabetes mellitus attending the paediatric diabetes clinic at Mulago National Referral Hospital, Kampala, Uganda. Following enrollment, we obtained details of clinical history and performed physical examination. Blood (plasma) was assayed to determine levels of antibodies to thyroid peroxidase (antiTPO), free thyroxine (FT4) and thyrotropin (TSH). The prevalence of thyroid autoimmunity was 7.3% (5/69). All antiTPO positive subjects were post pubertal, aged between 13-17 years with females comprising 3/5 of the antiTPO positive subjects. All study subjects were clinically euthyroid; however, 7.3% (5/69) of the study subjects had subclinical hypothyroidism. These data strengthen the argument for routine screening of all diabetic children and adolescents for thyroid autoimmunity (particularly anti-TPO) as recommended by international guidelines. We also recommend evaluation of thyroid function in diabetic children and adolescents to minimize the risk of undiagnosed thyroid dysfunction.

Hepatic OATP Transporter and Thyroid Hormone Receptor Interplay Determines Cholesterol and Glucose Homeostasis

PubMed Central

Meyer zu Schwabedissen, Henriette E.; Ware, Joseph A.; Finkelstein, David; Chaudhry, Amarjit S.; Lemay, Sara; Leon-Ponte, Matilde; Strom, Stephen C.; Zaher, Hani; Schwarz, Ute I.; Freeman, David J.; Schuetz, Erin G.; Tirona, Rommel G.; Kim, Richard B.

2011-01-01

The role of Organic Anion Transporting Polypeptides (OATPs), particularly the members of OATP1B-subfamily, in hepatocellular handling of endogenous and exogenous compounds is an important and emerging area of research. Using a mouse model lacking Slco1b2, the murine ortholog of the OATP1B-subfamily, we previously demonstrated that genetic ablation causes reduced hepatic clearance capacity for substrates. In this report we focused on the physiological function of the hepatic OATP1B transporters. First we studied the influence of the Oatp1b2 deletion on bile acid metabolism showing that lack of the transporter results in a significantly reduced expression of Cyp7a1 the key enzyme of bile acid synthesis, resulting in elevated cholesterol levels after high dietary fat challenge. Furthermore, Slco1b2−/− mice exhibited delayed clearance after oral glucose challenge resulting from reduced hepatic glucose uptake. In addition to increased hepatic glycogen content, Slco1b2−/−exhibited reduced glucose output after pyruvate challenge. This is in accordance with reduced hepatic expression of PEPCK in knockout mice. We show this phenotype is due to the loss of liver-specific Oatp1b2-mediated hepatocellular thyroid hormone entry, which then leads to reduced transcriptional activation of target genes of hepatic thyroid hormone receptor (TR) including the prior mentioned Cyp7a1 and Pepck, but also Dio1 and Glut2. Importantly, we assessed human relevance using a cohort of archived human livers where OATP1B1 expression was noted to be highly associated with TR target genes, especially for GLUT2. Furthermore, GLUT2 expression was significantly decreased in livers harboring a common genetic polymorphism in SLCO1B1. Conclusion Our findings reveal that OATP1B-mediated hepatic thyroid hormone entry is a key determinant of cholesterol and glucose homeostasis. PMID:21538436

Psychiatric Symptoms due to Thyroid Disease in a Female Adolescent

PubMed Central

Capetillo-Ventura, Nelly; Baeza, Inmaculada

2014-01-01

The hypothalamic-pituitary-thyroid axis is involved in the production of thyroid hormone which is needed to maintain the normal functioning of various organs and systems, including the central nervous system. This study reports a case of hypothyroidism in a fifteen-year-old female adolescent who was attended for psychiatric symptoms. This case reveals the importance of evaluating thyroid function in children and adolescents with neuropsychiatric symptoms. PMID:25436160

Thyroid Hormones and Thyroid Disease in Relation to Perchlorate Dose and Residence Near a Superfund Site

PubMed Central

Gold, Ellen B.; Blount, Benjamin C.; Rasor, Marianne O’Neill; Lee, Jennifer S.; Alwis, Udeni; Srivastav, Anup; Kim, Kyoungmi

2013-01-01

Background Perchlorate is a widely occurring contaminant, which can competitively inhibit iodide uptake and thus thyroid hormone production. The health effects of chronic low dose perchlorate exposure are largely unknown. Objectives In a community-based study, we compared thyroid function and disease in women with differing likelihoods of prior and current perchlorate exposure. Methods Residential blocks were randomly selected from areas: 1) with potential perchlorate exposure via drinking water; 2) with potential exposure to environmental contaminants; and 3) neighboring but without such exposures. Eligibility included having lived in the area for ≥6 months and aged 20–50 years during 1988–1996 (during documented drinking water well contamination). We interviewed 814 women and collected blood samples (assayed for thyroid stimulating hormone [TSH] and free thyroxine [fT4]) from 431 interviewed women. Daily urine samples were assayed for perchlorate and iodide for 178 premenopausal women with blood samples. We performed multivariable regression analyses comparing thyroid function and disease by residential area and by urinary perchlorate dose adjusted for urinary iodide levels. Results Residential location and current perchlorate dose were not associated with thyroid function or disease. Conclusions No persistent effect of perchlorate on thyroid function or disease was found several years after contaminated wells were capped. PMID:22968349

Transcriptome Network Analysis Reveals Aging-Related Mitochondrial and Proteasomal Dysfunction and Immune Activation in Human Thyroid

PubMed Central

Cho, Byuri Angela; Yoo, Seong-Keun; Song, Young Shin; Kim, Su-jin; Lee, Kyu Eun; Shong, Minho

2018-01-01

Background: Elucidating aging-related transcriptomic changes in human organs is necessary to understand the aging physiology and mechanisms, but little is known regarding the thyroid gland. We investigated aging-related transcriptomic alterations in the human thyroid gland and characterized the related molecular functions. Methods: Publicly available RNA sequencing data of 322 thyroid tissue samples from the Genotype-Tissue Expression project were analyzed. In addition, our own 64 RNA sequencing data of normal thyroid tissue samples were used as a validation set. To comprehensively evaluate the associations between aging and transcriptomic changes, we performed a weighted gene coexpression network analysis and pathway enrichment analysis. The thyroid differentiation score was then used for further analysis, defining the correlations between thyroid differentiation and aging. Results: The most significant aging-related transcriptomic change in thyroid was the downregulation of genes related to the mitochondrial and proteasomal functions (p = 3 × 10−6). Moreover, genes that are associated with immune processes were significantly upregulated with age (p = 3 × 10−4), and all of them overlapped with the upregulated genes in the thyroid glands affected by lymphocytic thyroiditis. Furthermore, these aging-related changes were not significantly different according to sex, but in terms of the thyroid differentiation, females were more susceptible to aging-related changes (p for trend = 0.03). Conclusions: Aging-related transcriptomic changes in the thyroid gland were associated with mitochondrial and proteasomal dysfunction, loss of differentiation, and activation of autoimmune processes. Our results provide clues to better understanding the age-related decline in thyroid function and higher susceptibility to autoimmune thyroid disease. PMID:29652618

A rare cause of hyperthyroidism: functioning thyroid metastases.

PubMed

Gardner, Daphne; Ho, Su Chin

2014-10-09

Hyperthyroidism is a common medical problem that is readily treated with antithyroid medications. However, attributing the correct aetiology of hyperthyroidism alters management and outcome. We present a case of a 66-year-old woman with a seemingly common problem of hyperthyroidism associated with a goitre, which was initially attributed to a toxic nodule. However, Tc-99m pertechnetate uptake scan and thyroid-stimulating hormone receptor antibody were negative, inconsistent with a toxic nodule or Grave's disease. Her thyroid function tests proved difficult to control over the next few months. She eventually proceeded to a total thyroidectomy and histology revealed follicular variant papillary thyroid carcinoma. She was started on levothyroxine postoperatively but developed severe hyperthyroidism, revealing the cause of hyperthyroidism to be autonomously functioning thyroid metastases. Although functioning thyroid metastases are very rare, they need to be considered among the differential diagnoses of hyperthyroidism, as there are nuances in management that could alter the eventual outcome. 2014 BMJ Publishing Group Ltd.

Maternal Thyroid Function in Early Pregnancy and Neuropsychological Performance of the Child at 5 Years of Age.

PubMed

Andersen, Stine Linding; Andersen, Stig; Liew, Zeyan; Vestergaard, Peter; Olsen, Jørn

2018-02-01

Abnormal maternal thyroid function in pregnancy may impair fetal brain development, but more evidence is needed to refine and corroborate the hypothesis. To estimate the association between maternal thyroid function in early pregnancy and neuropsychological performance of the child at 5 years of age. Follow-up study. A cohort of 1153 women and their children sampled from the Danish National Birth Cohort. Maternal thyroid-stimulating hormone (TSH) and free thyroxine (fT4) were measured in stored biobank sera from early pregnancy. Child neuropsychological test results (Wechsler Intelligence Scale/Test of Everyday Attention), test of motor function (Movement Assessment Battery), and results of parent and teacher reports (Behavior Rating Inventory of Executive Function/Strengths and Difficulties Questionnaire). Altogether 145 children (12.6%) were born to mothers with abnormal thyroid function in the early pregnancy. High maternal TSH and low fT4 were associated with lower child verbal intelligence quotient (adjusted mean difference TSH ≥ 10 mIU/L vs 0.1 to 2.49 mIU/L, -8.9 [95% confidence interval (CI), -15 to -2.4]; fT4 < 10 pmol/l vs 12.0 to 18.99 pmol/l, -13 [95% CI, -19 to -7.3]). Abnormal maternal thyroid function was also associated with adverse motor function and teacher-reported problems of executive function and behavior, and these associations were dominated by exposure to maternal hypothyroxinemia. Maternal thyroid hormone abnormalities were associated with adverse neuropsychological function of the child at 5 years of age. For intelligence, marked hypothyroidism was important, whereas for motor function and executive and behavior problems, maternal hypothyroxinemia was predominant. Copyright © 2017 Endocrine Society

Preoperative thyroid function and weight loss after bariatric surgery.

PubMed

Neves, João Sérgio; Souteiro, Pedro; Oliveira, Sofia Castro; Pedro, Jorge; Magalhães, Daniela; Guerreiro, Vanessa; Costa, Maria Manuel; Bettencourt-Silva, Rita; Santos, Ana Cristina; Queirós, Joana; Varela, Ana; Freitas, Paula; Carvalho, Davide

2018-05-16

Thyroid function has an important role on body weight regulation. However, the impact of thyroid function on weight loss after bariatric surgery is still largely unknown. We evaluated the association between preoperative thyroid function and the excess weight loss 1 year after surgery, in 641 patients with morbid obesity who underwent bariatric surgery. Patients with a history of thyroid disease, treatment with thyroid hormone or antithyroid drugs and those with preoperative evaluation consistent with overt hypothyroidism or hyperthyroidism were excluded. The preoperative levels of TSH and FT4 were not associated with weight loss after bariatric surgery. The variation of FT3 within the reference range was also not associated with weight loss. In contrast, the subgroup with FT3 above the reference range (12.3% of patients) had a significantly higher excess weight loss than patients with normal FT3. This difference remained significant after adjustment for age, sex, BMI, type of surgery, TSH and FT4. In conclusion, we observed an association between high FT3 and a greater weight loss after bariatric surgery, highlighting a group of patients with an increased benefit from this intervention. Our results also suggest a novel hypothesis: the pharmacological modulation of thyroid function may be a potential therapeutic target in patients undergoing bariatric surgery.

Bioprinting of a functional vascularized mouse thyroid gland construct.

PubMed

Bulanova, Elena A; Koudan, Elizaveta V; Degosserie, Jonathan; Heymans, Charlotte; Pereira, Frederico DAS; Parfenov, Vladislav A; Sun, Yi; Wang, Qi; Akhmedova, Suraya A; Sviridova, Irina K; Sergeeva, Natalia S; Frank, Georgy A; Khesuani, Yusef D; Pierreux, Christophe E; Mironov, Vladimir A

2017-08-18

Bioprinting can be defined as additive biofabrication of three-dimensional (3D) tissues and organ constructs using tissue spheroids, capable of self-assembly, as building blocks. The thyroid gland, a relatively simple endocrine organ, is suitable for testing the proposed bioprinting technology. Here we report the bioprinting of a functional vascularized mouse thyroid gland construct from embryonic tissue spheroids as a proof of concept. Based on the self-assembly principle, we generated thyroid tissue starting from thyroid spheroids (TS) and allantoic spheroids (AS) as a source of thyrocytes and endothelial cells (EC), respectively. Inspired by mathematical modeling of spheroid fusion, we used an original 3D bioprinter to print TS in close association with AS within a collagen hydrogel. During the culture, closely placed embryonic tissue spheroids fused into a single integral construct, EC from AS invaded and vascularized TS, and epithelial cells from the TS progressively formed follicles. In this experimental setting, we observed formation of a capillary network around follicular cells, as observed during in utero thyroid development when thyroid epithelium controls the recruitment, invasion and expansion of EC around follicles. To prove that EC from AS are responsible for vascularization of the thyroid gland construct, we depleted endogenous EC from TS before bioprinting. EC from AS completely revascularized depleted thyroid tissue. The cultured bioprinted construct was functional as it could normalize blood thyroxine levels and body temperature after grafting under the kidney capsule of hypothyroid mice. Bioprinting of functional vascularized mouse thyroid gland construct represents a further advance in bioprinting technology, exploring the self-assembling properties of tissue spheroids.

Implication from thyroid function decreasing during chemotherapy in breast cancer patients: chemosensitization role of triiodothyronine

PubMed Central

2013-01-01

Background Thyroid hormones have been shown to regulate breast cancer cells growth, the absence or reduction of thyroid hormones in cells could provoke a proliferation arrest in G0-G1 or weak mitochondrial activity, which makes cells insensitive to therapies for cancers through transforming into low metabolism status. This biological phenomenon may help explain why treatment efficacy and prognosis vary among breast cancer patients having hypothyroid, hyperthyroid and normal function. Nevertheless, the abnormal thyroid function in breast cancer patients has been considered being mainly caused by thyroid diseases, few studied influence of chemotherapy on thyroid function and whether its alteration during chemotherapy can influence the respose to chemotherapy is still unclear. So, we aimed to find the alterations of thyroid function and non-thyroidal illness syndrome (NTIS) prevalence druing chemotherapy in breast cancer patients, and investigate the influence of thyroid hormones on chemotherapeutic efficacy. Methods Thyroid hormones and NTIS prevalence at initial diagnosis and during chemotherapy were analyzed in 685 breast diseases patients (369 breast cancer, 316 breast benign lesions). The influence of thyroid hormones on chemotherapeutic efficacy was evaluated by chemosensitization test, to compare chemotherapeutic efficacy between breast cancer cells with chemotherapeutics plus triiodothyronine (T3) and chemotherapeutics only. Results In breast cancer, NTIS prevalence at the initial diagnosis was higher and increased during chemotherapy, but declined before the next chemotherapeutic course. Thyroid hormones decreased signigicantly during chemotherapy. T3 can enhance the chemosensitivity of MCF-7 to 5-Fu and taxol, with progression from G0-G1 phase to S phase. The similar chemosensitization role of T3 were found in MDA-MB-231. We compared chemotherapeutic efficacy among groups with different usage modes of T3, finding pretreatment with lower dose of T3, using higher dose of T3 together with 5-Fu or during chemotherapy with 5-Fu were all available to achieve chemosensitization, but pretreatment with lower dose of T3 until the end of chemotherapy may be a safer and more efficient therapy. Conclusions Taken together, thyroid hormones decreasing during chemotherapy was found in lots of breast cancer patients. On the other hand, thyroid hormones can enhance the chemotherapeutic efficacy through gatherring tumor cells in actively proliferating stage, which may provide a new adjuvant therapy for breast cancer in furture, especially for those have hypothyroidism during chemotherapy. PMID:23829347

Thyroid disrupting chemicals: Mechanisms and mixtures

EPA Science Inventory

Environmental contaminants are known to act as thyroid disrupting chemicals (TDCs). Broadly defined, TDCs are xenobiotics that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormone (TH) homeostasis, or change circulating o...

Accidental finding of Hashimoto-like thyroiditis in male B.U.T. 6 turkeys at slaughter.

PubMed

Plesch, P; Schade, B; Breithaupt, A; Bellof, G; Kienzle, E

2014-10-01

In the context of a study on the tolerance of rapeseed meal in B.U.T. 6 turkeys, thyroid glands were histologically and immunohistochemically examined because of potential thyreostatic effects. In all groups including the controls with no rapeseed meal in their food, there was a high incidence of lymphocytic infiltration and thyroiditis (14% of thyroids with moderate to severe lymphocytic thyroiditis). Thirty per cent of mononuclear inflammatory cells were immunohistochemically identified as T cells. There were occasional accumulations of PAX-5 labelled cells, indicating germinal centre development. These lesions resemble Hashimoto's disease in humans. The effect on thyroid function is unknown. Mild hypothyreosis might enhance productivity but also explain dispositions towards diseases seen in context with thyroid dysfunction such as skin diseases (foot pad disease?) and cardiovascular problems. Further studies on thyroid function in these turkeys are needed. Journal of Animal Physiology and Animal Nutrition © 2013 Blackwell Verlag GmbH.

Developmental Thyroid Hormone Insufficiency Reduces Expression of Brain-Derived Neurotrophic Factor (BDNF) in Adults But Not in Neonates

EPA Science Inventory

Brain-derived neurotrophic factor (BDNF) is a neurotrophin critical for many developmental and physiological aspects of CNS function. Severe hypothyroidism in the early neonatal period results in developmental and cognitive impairments and reductions in mRNA and protein expressio...

[The thyroid gland in emotional and pain stress].

PubMed

Akhmetov, I Z

1987-01-01

The reaction of wild rodent thyroid gland on emotional and painful stress appearing as a result of animal's catching has been studied. The thyroid activity has been shown to raise considerably during the primary stage of stress reaction. Later on the function of the gland normalizes in animals without trauma and in traumatized animals it becomes weaker. The complete normalization of the thyroid function in traumatized animals coincides with osteal regeneration according to time.

Exaggerated thyroid stimulating hormone secretion in children exposed to the Chernobyl nuclear reactor catastrophe.

PubMed

Boyarskaya, O Y; Kopilova, O V

2008-02-01

We present results of a long-term study of the morpho-functional state of the thyroid gland and of the functional capacities of the hypothalamic-hypophyseal system, as shown by thyrotropin releasing hormone stimulation, in different groups of children who suffered from the Chernobyl accident. It was shown that the thyroid gland of the children who were evacuated from the 30-km zone was damaged most severely due to the influence of radioactive iodine (131I). Living on radionuclide-polluted territories in conditions of iodine deficiency has been an additional contributory factor in the development of thyroid gland diseases. Latent functional deficiency of the hypothalamic-hypophyseal system can be one of the reasons leading to oncopathology of the thyroid gland.

Autoimmune thyroid disease in pregnancy: a review.

PubMed

Galofre, Juan C; Davies, Terry F

2009-11-01

The maternal physiological changes that occur in normal pregnancy induce complex endocrine and immune responses. During a normal pregnancy, thyroid gland volume may enlarge, and thyroid hormone production increases. Hence, the interpretation of thyroid function during gestation needs to be adjusted according to pregnancy-specific ranges. The elevated prevalence of gestation-related thyroid disorders (10%-15%) and the important repercussions for both mother and fetus reported in multiple studies throughout the world denote, in our opinion, the necessity for routine thyroid function screening both before and during pregnancy. Once thyroid dysfunction is suspected or confirmed, management of the thyroid disorder necessitates regular monitoring in order to ensure a successful outcome. The aim of treating hyperthyroidism in pregnancy with antithyroid drugs is to maintain serum thyroxine (T(4)) in the upper normal range of the assay used with the lowest possible dose of drug, whereas in hypothyroidism, the goal is to return serum thyroid-stimulating hormone (TSH) to the range between 0.5 and 2.5 mU/L.

Autoimmune Thyroid Disease in Pregnancy: A Review

PubMed Central

Galofre, Juan C.

2009-01-01

Abstract The maternal physiological changes that occur in normal pregnancy induce complex endocrine and immune responses. During a normal pregnancy, thyroid gland volume may enlarge, and thyroid hormone production increases. Hence, the interpretation of thyroid function during gestation needs to be adjusted according to pregnancy-specific ranges. The elevated prevalence of gestation-related thyroid disorders (10%–15%) and the important repercussions for both mother and fetus reported in multiple studies throughout the world denote, in our opinion, the necessity for routine thyroid function screening both before and during pregnancy. Once thyroid dysfunction is suspected or confirmed, management of the thyroid disorder necessitates regular monitoring in order to ensure a successful outcome. The aim of treating hyperthyroidism in pregnancy with antithyroid drugs is to maintain serum thyroxine (T4) in the upper normal range of the assay used with the lowest possible dose of drug, whereas in hypothyroidism, the goal is to return serum thyroid-stimulating hormone (TSH) to the range between 0.5 and 2.5 mU/L. PMID:19951221

Ectopic Thyroid Tissue in Submandibular and Infrahyoid Region

PubMed Central

Mutlu, Vahit

2014-01-01

The thyroid is the first endocrine gland to form during embryogenesis. At this stage, incomplete or anomalous migration of thyroid tissue causes ectopic localization of the gland. Submandibular ectopic thyroid tissue with a coexisting normally located thyroid gland is extremely rare. In this case aimed to present the findings of the 65-years-old female patient who is bilateral subtotal thyroidectomy operation performed for multinodular goiter of 12 years ago. Case, painless mass in the right submandibular and infrahyoid region for 6 months was admitted to our clinic with complaints. Result of contrast-enhanced neck computed tomography, ultrasound-guided fine-needle aspiration biopsy and thyroid scintigraphy were found of functional residual thyroid tissue in the normal localization as well as 2×3 cm mass in the submandibular area and 1×2 cm mass lesion in the infrahyoid region. The patient referred to excisional biopsy. Normal thyroid follicules and no evidence of malignancy were found in specimen pathologically. Postoperative follow-up of thyroid function tests were normal. PMID:25610328

[Effect of aceclofenac on thyroid hormone binding and thyroid function].

PubMed

Nadler, K; Buchinger, W; Semlitsch, G; Pongratz, R; Rainer, F

2000-01-01

Influences of non-steroidal anti-inflammatory drugs (NSAID) on concentrations of thyroid hormones are known for a long time. These effects could be explained with interference between NSAIDs and thyroid hormone binding. We investigated the effects of a single dose of aceclofenac on thyroid function and thyroid hormone binding in 18 healthy volunteers. Serum levels of free thyroid hormones (FT3, FT4) and thyrotropin (TSH) were measured with commercial available kids and thyroid hormone binding was estimated with a specially modified horizontal argarose-gel-electrophoresis prior to and 2 hours after receiving a single dose of aceclofenac. We found a significant decrease in T3 binding on TBG and a significant increase of albumin-bound T3. All other investigated thyroid hormone binding parameters, FT3 and FT4, showed no significant changes. We conclude that aceclofenac leads to a significant redistribution of T3 protein binding. These effects seem to be explained by T3 displacement from TBG induced by aceclofenac.

Effects of Ammonium Perchlorate on Thyroid Function in Developing Fathead Minnows, Pimephales promelas

PubMed Central

Crane, Helen M.; Pickford, Daniel B.; Hutchinson, Thomas H.; Brown, J. Anne

2005-01-01

Perchlorate is a known environmental contaminant, largely due to widespread military use as a propellant. Perchlorate acts pharmacologically as a competitive inhibitor of thyroidal iodide uptake in mammals, but the impacts of perchlorate contamination in aquatic ecosystems and, in particular, the effects on fish are unclear. Our studies aimed to investigate the effects of concentrations of ammonium perchlorate that can occur in the environment (1, 10, and 100 mg/L) on the development of fathead minnows, Pimephales promelas. For these studies, exposures started with embryos of < 24-hr postfertilization and were terminated after 28 days. Serial sectioning of thyroid follicles showed thyroid hyperplasia with increased follicular epithelial cell height and reduced colloid in all groups of fish that had been exposed to perchlorate for 28 days, compared with control fish. Whole-body thyroxine (T4) content (a measure of total circulating T4) in fish exposed to 100 mg/L perchlorate was elevated compared with the T4 content of control fish, but 3,5,3′-triiodothyronine (T3) content was not significantly affected in any exposure group. Despite the apparent regulation of T3, after 28 days of exposure to ammonium perchlorate, fish exposed to the two higher levels (10 and 100 mg/L) were developmentally retarded, with a lack of scales and poor pigmentation, and significantly lower wet weight and standard length than were control fish. Our study indicates that environmental levels of ammonium perchlorate affect thyroid function in fish and that in the early life stages these effects may be associated with developmental retardation. PMID:15811828

Emerging integrated nanoclay-facilitated drug delivery system for papillary thyroid cancer therapy

NASA Astrophysics Data System (ADS)

Zhang, Yi; Long, Mei; Huang, Peng; Yang, Huaming; Chang, Shi; Hu, Yuehua; Tang, Aidong; Mao, Linfeng

2016-09-01

Nanoclay can be incorporated into emerging dual functional drug delivery systems (DDSs) to promote efficiency in drug delivery and reduce the toxicity of doxorubicin (DOX) used for thyroid cancer treatment. This paper reports the expansion of the basal spacing of kaolinite nanoclay was expanded from 0.72 nm to 0.85 nm, which could provide sufficiently spacious site for hosting doxorubicin molecules and controlling the diffusion rate. A targeted design for papillary thyroid cancer cells was achieved by introducing KI, which is consumed by the sodium-iodide symporter (NIS). As indicated by MTT assays, confocal laser scanning microscopy and bio-TEM observations, methoxy-intercalated kaolinite (KaolinMeOH) exhibited negligible cytotoxicity against papillary thyroid cancer cells. By contrast, DOX-KaolinMeOH showed dose-dependent therapeutic effects in vitro, and KI@DOX-KaolinMeOH was found to act as a powerful targeted therapeutic drug. Furthermore, active and passive targeting strategies played a role in the accumulation of the drug molecules, as verified by an in vivo bio-distribution analysis.

Autonomously hyperfunctioning cystic nodule harbouring thyroid carcinoma - Case report and literature review.

PubMed

Lima, Maria João; Soares, Virgínia; Koch, Pedro; Silva, Artur; Taveira-Gomes, António

2018-01-01

Hyperthyroidism is rarely associated with malignancy, but it cannot rule out thyroid cancer. Although there is published data describing this coexistence, thyroid carcinomas inside autonomously functioning nodules are uncommon. A 49-year-old woman presented with a cervical mass, unexplained weight loss and anxiousness, sweating and insomnia. On physical examination, she had a palpable left thyroid nodule. Thyroid function tests showed suppressed TSH (<0,1 uUI/mL), thyroxine 1,44 ng/dL (normal range 0,70-1,48) and triiodothyronine 4,33 pg/mL (normal range 1,71-3,71). Ultrasound imaging revealed a left lobe, 4 cm partial cystic nodule. 99mTC thyroid scintigraphy showed a hyperfunctioning nodule with suppression of the remainder parenchyma. Fine-needle aspiration cytology was nondiagnostic (cystic fluid). The patient was started on thiamazole 5 mg daily with subsequent normalization of thyroid function, but she developed cervical foreign body sensation and a left hemithyroidectomy was performed. Histology showed a 4 cm cystic nodule with a follicular variant papillary carcinoma and the patient underwent completion thyroidectomy, followed by radio-iodine ablation. Published literature showed an increased prevalence of autonomously functioning nodules, harbouring thyroid carcinomas in adults. Papillary carcinoma is the most frequently described but the follicular variant is rare. Although rare, thyroid cancer is not definitively excluded in hyperthyroid patients and it should always be considered as differential diagnosis. Copyright © 2018. Published by Elsevier Ltd.

Metals in blood and urine, and thyroid function among adults in the United States 2007-2008

EPA Science Inventory

Abstract Background: The thyroid is integral to regulation of development and metabolism. Certain metals have been shown to affect thyroid function in occupationally exposed persons, but few studies have been conducted in the general population. Objective: To evaluate the as...

Cosmos 1887 mission overview - Effects of microgravity on rat body and adrenal weights and plasma constituents

NASA Technical Reports Server (NTRS)

Grindeland, R. E.; Vasques, M.; Arnaud, S. B.; Popova, I. A.

1990-01-01

Tissues of male, specific pathogen-free Wistar rats flown on the Cosmos 1887 biosatellite are studied. First the mission is described, and then analytical methods are outlined. It is noted that flight rats grew more slowly and had larger adrenal glands than earth gravity controls. Analysis of plasma reveals increased concentrations of hepatic alkaline phosphatase, glucose, urea nitrogen, and creatinine in flight rats. In contrast, electrolytes, total protein, albumin, corticosteron, prolactin, and immunoreactive growth hormone levels are unchanged. However, testosterone concentration is marginally decreased after flight and thyroid hormone levels are suggestive of reduced thyroid function.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yu, Yao; Chen, Josephine; Leary, Celeste I.

Radiation of the low neck can be accomplished using split-field intensity-modulated radiation therapy (sf-IMRT) or extended-field intensity-modulated radiation therapy (ef-IMRT). We evaluated the effect of these treatment choices on target coverage and thyroid and larynx doses. Using data from 14 patients with cancers of the oropharynx, we compared the following 3 strategies for radiating the low neck: (1) extended-field IMRT, (2) traditional split-field IMRT with an initial cord-junction block to 40 Gy, followed by a full-cord block to 50 Gy, and (3) split-field IMRT with a full-cord block to 50 Gy. Patients were planned using each of these 3 techniques.more » To facilitate comparison, extended-field plans were normalized to deliver 50 Gy to 95% of the neck volume. Target coverage was assessed using the dose to 95% of the neck volume (D{sub 95}). Mean thyroid and larynx doses were computed. Extended-field IMRT was used as the reference arm; the mean larynx dose was 25.7 ± 7.4 Gy, and the mean thyroid dose was 28.6 ± 2.4 Gy. Split-field IMRT with 2-step blocking reduced laryngeal dose (mean larynx dose 15.2 ± 5.1 Gy) at the cost of a moderate reduction in target coverage (D{sub 95} 41.4 ± 14 Gy) and much higher thyroid dose (mean thyroid dose 44.7 ± 3.7 Gy). Split-field IMRT with initial full-cord block resulted in greater laryngeal sparing (mean larynx dose 14.2 ± 5.1 Gy) and only a moderately higher thyroid dose (mean thyroid dose 31 ± 8 Gy) but resulted in a significant reduction in target coverage (D{sub 95} 34.4 ± 15 Gy). Extended-field IMRT comprehensively covers the low neck and achieves acceptable thyroid and laryngeal sparing. Split-field IMRT with a full-cord block reduces laryngeal doses to less than 20 Gy and spares the thyroid, at the cost of substantially reduced coverage of the low neck. Traditional 2-step split-field IMRT similarly reduces the laryngeal dose but also reduces low-neck coverage and delivers very high doses to the thyroid.« less

The effects of methimazole on development of the fathead minnow, Pimephales promelas, from embryo to adult.

PubMed

Crane, Helen M; Pickford, Daniel B; Hutchinson, Thomas H; Brown, J Anne

2006-10-01

The importance of thyroid hormones in regulating early developmental processes of many amphibian and fish species is well known, but the impacts of exposure to disrupters of thyroid homeostasis during the embryo-larval-juvenile transitions are unclear. To investigate these impacts, fathead minnows, Pimephales promelas, were exposed to a model thyroid axis disrupter, methimazole, an inhibitor of thyroid hormone synthesis, at control (0), 32, 100, and 320 mug/l, starting at <24-h postfertilization, for 28, 56, and 83/84 days postfertilization (dpf). Thyroid disruption was evident at 28 dpf, when survival was significantly reduced by 32 or 100 mug/l methimazole concomitant with a reduced thyroxine (T(4)) content. However, the T(3) content of these fish was similar to that of control fish, and body mass was unaffected (as in all groups), suggesting compensatory mechanisms overcame reduced T(4) synthesis. At the highest concentration of methimazole (320 mug/l), activation of feedback mechanisms on the hypothalamic-pituitary-thyroid axis was suggested by the normal T(4) content after 28 dpf exposure to methimazole, although triiodothyronine (T(3)) content of these fish was significantly reduced. The generally less pronounced disruption of thyroid hormone homeostasis after 56 days exposure to methimazole also suggests compensatory mechanisms in juvenile/adult fish that may regulate T(4) content, despite exposure to methimazole at 32 or 100 mug/l (in fish held in 320 mug/l methimazole, the T(4) content was significantly higher than in controls). Whole body T(3) content at 56 dpf was significantly depressed only in fish held in 100 mug/l methimazole. By 83/84 dpf, length, body mass, and thyroid hormone concentrations were similar in all experimental groups and controls, indicating that adult fish may achieve regulation of their thyroid axis despite prolonged exposures to thyroid disruptors throughout early development.

[Multifactorial analysis of effects of mothers' autoimmune thyroid disease on their infants' intellectual development].

PubMed

Zhu, Hong; Zhao, Zheng-yan; Jiang, You-jun; Liang, Li; Wang, Ji-yue; Mao, Hua-qing; Zou, Chao-chun; Chen, Li-qin; Qu, Yi-ping

2005-05-01

To analyze factors relevant to retarded intellectual development in infants born to mothers with autoimmune disease of thyroid. All the term newborns born to mothers with autoimmune thyroid disease (selection criteria) without asphyxia in all county, city, and provincial hospitals in Zhejiang province (except for Ningbo City) from July 2001 to June 2003 were enrolled through Zhejiang provincial neonatal disease screening network system. The control group was consisted of the neonates who were born to mothers without thyroid disease in these hospitals during the same period. Heel capillary blood samples were collected from the neonates older than 3 days in local hospitals and sent to the center of Zhejiang provincial neonatal disease screening network system. TSH levels were measured by Time Difference Fluorescent Analysis Device (1420 II type, EGG Company, US). If the level of TSH was higher than 9 mU/L, their mothers were called back to the center with their infants within 3 days. If the level of TSH was normal, they were called back to hospitals at age of 28 - 35 days of infants. The pattern of maternal thyroid disease, duration, thyroid function, the history of maternal drug administration, maternal age, gestational age and body weight of the neonates were recorded. The neonatal and maternal serum thyroid function tests were re-performed and the serum TPOAb, TGAb, TRAb and TSAb levels in both neonates and their mothers were measured as well. A 1-year follow-up study was done and all these subjects were investigated by means of Gesell development schedules by special investigators at the age of 1, 3, 6 and 12 months. The results were expressed as developmental quotient. Case-sectional study was performed. Statistical analyses were conducted using SPSS software. The multiple logistic regression analysis was used to analyze factors which might have effect on infantile personal-social ability, adaptive ability, gross motor ability or the fine-motor ability. One-way ANOVA was used to compare those five subfields ability followed by LSD multiple comparisons and Dunnet's C test was used when variances were not equal. Correlation analysis was used to compare the anti-thyroid antibody between neonates and their mothers. Poor personal-social ability, adaptive ability, gross motor ability and fine motor ability of infants born to mothers with autoimmune thyroid diseases were found as compared to the infants born to healthy mothers (P < 0.01). Moreover, the infants born to mothers with Hashimoto's thyroiditis had significantly poorer fine motor ability and adaptive ability than those born to mothers with Grave's disease (P < 0.05). The Spearman correlation coefficients of TPOAb, TGAb, TRAb and TSAb were 0.636, 0.574, 0.619 and 0.473, respectively, and all the P values were lower than 0.01.The multifactor logistic regression analysis showed that infantile TPOAb levels and maternal TRAb levels were associated with infantile personal-social ability, adaptive ability, and gross motor; while maternal TPOAb levels and thyroid function during gestation were associated with infantile fine-motor ability (P < 0.05). Maternal autoimmune thyroid diseases during pregnancy had adverse effects on intellectual development of infants. The maternal levels of TPOAb, TRAb and thyroid status were associated with the infantile personal-social ability, adaptive ability, gross motor and fine motor development. In order to reduce the effect on infant, it is necessary to treat adequately the maternal autoimmune thyroid diseases during pregnancy.

PCBs Alter Dopamine Mediated Function in Aging Workers

DTIC Science & Technology

2007-01-01

Thyroid Hormone Function Analysis of serum samples collected for thyroid hormone function (T3, T4, free T3, free T4, and TSH levels) has been conducted by...Thyroid Hormone Measure Mean sem Mean sem TSH 2.06 0.13 2.55 0.36 T4 7.94 0.18 8.72 0.22 Free T4 1.23 0.02 1.22 0.03 T3 133 3.05 122 2.74...FreeT3 5.31 0.08 4.56 0.08 TSH = Thyroid Stimulating Hormone T4 = Thyroxine T3 = 3,5,3-Triidothyronine Investigators Meetings and

Utility of Quantitative Parameters from Single-Photon Emission Computed Tomography/Computed Tomography in Patients with Destructive Thyroiditis.

PubMed

Kim, Ji-Young; Kim, Ji Hyun; Moon, Jae Hoon; Kim, Kyoung Min; Oh, Tae Jung; Lee, Dong-Hwa; So, Young; Lee, Won Woo

2018-01-01

Quantitative parameters from Tc-99m pertechnetate single-photon emission computed tomography/computed tomography (SPECT/CT) are emerging as novel diagnostic markers for functional thyroid diseases. We intended to assess the utility of SPECT/CT parameters in patients with destructive thyroiditis. Thirty-five destructive thyroiditis patients (7 males and 28 females; mean age, 47.3 ± 13.0 years) and 20 euthyroid patients (6 males and 14 females; mean age, 45.0 ± 14.8 years) who underwent Tc-99m pertechnetate quantitative SPECT/CT were retrospectively enrolled. Quantitative parameters from the SPECT/CT (%uptake, standardized uptake value [SUV], thyroid volume, and functional thyroid mass [SUVmean × thyroid volume]) and thyroid hormone levels were investigated to assess correlations and predict the prognosis for destructive thyroiditis. The occurrence of hypothyroidism was the outcome for prognosis. All the SPECT/CT quantitative parameters were significantly lower in the 35 destructive thyroiditis patients compared to the 20 euthyroid patients using the same SPECT/CT scanner and protocol ( p < 0.001 for all parameters). T3 and free T4 did not correlate with any SPECT/CT parameters, but thyroid-stimulating hormone (TSH) significantly correlated with %uptake ( p = 0.004), SUVmean ( p < 0.001), SUVmax ( p = 0.002), and functional thyroid mass ( p < 0.001). Of the 35 destructive thyroiditis patients, 16 progressed to hypothyroidism. On univariate and multivariate analyses, only T3 levels were associated with the later occurrence of hypothyroidism ( p = 0.002, exp(β) = 1.022, 95% confidence interval: 1.008 - 1.035). Novel quantitative SPECT/CT parameters could discriminate patients with destructive thyroiditis from euthyroid patients, suggesting the robustness of the quantitative SPECT/CT approach. However, disease progression of destructive thyroiditis could not be predicted using the parameters, as these only correlated with TSH, but not with T3, the sole predictor of the later occurrence of hypothyroidism.

Utility of Quantitative Parameters from Single-Photon Emission Computed Tomography/Computed Tomography in Patients with Destructive Thyroiditis

PubMed Central

Kim, Ji-Young; Kim, Ji Hyun; Moon, Jae Hoon; Kim, Kyoung Min; Oh, Tae Jung; Lee, Dong-Hwa; So, Young

2018-01-01

Objective Quantitative parameters from Tc-99m pertechnetate single-photon emission computed tomography/computed tomography (SPECT/CT) are emerging as novel diagnostic markers for functional thyroid diseases. We intended to assess the utility of SPECT/CT parameters in patients with destructive thyroiditis. Materials and Methods Thirty-five destructive thyroiditis patients (7 males and 28 females; mean age, 47.3 ± 13.0 years) and 20 euthyroid patients (6 males and 14 females; mean age, 45.0 ± 14.8 years) who underwent Tc-99m pertechnetate quantitative SPECT/CT were retrospectively enrolled. Quantitative parameters from the SPECT/CT (%uptake, standardized uptake value [SUV], thyroid volume, and functional thyroid mass [SUVmean × thyroid volume]) and thyroid hormone levels were investigated to assess correlations and predict the prognosis for destructive thyroiditis. The occurrence of hypothyroidism was the outcome for prognosis. Results All the SPECT/CT quantitative parameters were significantly lower in the 35 destructive thyroiditis patients compared to the 20 euthyroid patients using the same SPECT/CT scanner and protocol (p < 0.001 for all parameters). T3 and free T4 did not correlate with any SPECT/CT parameters, but thyroid-stimulating hormone (TSH) significantly correlated with %uptake (p = 0.004), SUVmean (p < 0.001), SUVmax (p = 0.002), and functional thyroid mass (p < 0.001). Of the 35 destructive thyroiditis patients, 16 progressed to hypothyroidism. On univariate and multivariate analyses, only T3 levels were associated with the later occurrence of hypothyroidism (p = 0.002, exp(β) = 1.022, 95% confidence interval: 1.008 – 1.035). Conclusion Novel quantitative SPECT/CT parameters could discriminate patients with destructive thyroiditis from euthyroid patients, suggesting the robustness of the quantitative SPECT/CT approach. However, disease progression of destructive thyroiditis could not be predicted using the parameters, as these only correlated with TSH, but not with T3, the sole predictor of the later occurrence of hypothyroidism. PMID:29713225

Is it possible to diagnose canine hypothyroidism?

PubMed

Panciera, D L

1999-04-01

A definitive diagnosis of hypothyroidism can be difficult because of the many clinical abnormalities associated with thyroid hormone deficiency, and the lack of readily available diagnostic tests with high sensitivity and specificity. Thyroid function tests should be performed only in dogs with clinical findings consistent with hypothyroidism. Measurement of serum total thyroxine (T4) concentration is a useful initial screening test since most hypothyroid dogs have values below the reference range. Serum free T4 concentration measured by equilibrium dialysis is a more sensitive and specific test of thyroid function than total T4 and is particularly useful in dogs with non-thyroidal illness or atypical clinical signs. Measurement of serum endogenous thyroid-stimulating hormone concentration is also helpful, but many hypothyroid dogs have normal results. The gold standard for diagnosis of hypothyroidism remains the thyroid-stimulating hormone response test. It should be used to confirm hypothyroidism when other tests do not agree with the clinical impression or if atypical signs or non-thyroidal illness exist or there has been administration of drugs known to alter thyroid function tests. Ultimately, a positive response to treatment is expected in hypothyroid dogs treated appropriately with levothyroxine.

Recent Advances in Thyroid Hormone Regulation: Toward a New Paradigm for Optimal Diagnosis and Treatment

PubMed Central

Hoermann, Rudolf; Midgley, John E. M.; Larisch, Rolf; Dietrich, Johannes W.

2017-01-01

In thyroid health, the pituitary hormone thyroid-stimulating hormone (TSH) raises glandular thyroid hormone production to a physiological level and enhances formation and conversion of T4 to the biologically more active T3. Overstimulation is limited by negative feedback control. In equilibrium defining the euthyroid state, the relationship between TSH and FT4 expresses clusters of genetically determined, interlocked TSH–FT4 pairs, which invalidates their statistical correlation within the euthyroid range. Appropriate reactions to internal or external challenges are defined by unique solutions and homeostatic equilibria. Permissible variations in an individual are much more closely constrained than over a population. Current diagnostic definitions of subclinical thyroid dysfunction are laboratory based, and do not concur with treatment recommendations. An appropriate TSH level is a homeostatic concept that cannot be reduced to a fixed range consideration. The control mode may shift from feedback to tracking where TSH becomes positively, rather than inversely related with FT4. This is obvious in pituitary disease and severe non-thyroid illness, but extends to other prevalent conditions including aging, obesity, and levothyroxine (LT4) treatment. Treatment targets must both be individualized and respect altered equilibria on LT4. To avoid amalgamation bias, clinically meaningful stratification is required in epidemiological studies. In conclusion, pituitary TSH cannot be readily interpreted as a sensitive mirror image of thyroid function because the negative TSH–FT4 correlation is frequently broken, even inverted, by common conditions. The interrelationships between TSH and thyroid hormones and the interlocking elements of the control system are individual, dynamic, and adaptive. This demands a paradigm shift of its diagnostic use. PMID:29375474

Thyroid function status and plasma lipids among cardiology patients in Georgia.

PubMed

Chapidze, G; Enquobahrie, D; Kapanadze, S; Dolidze, N; Soh, J; Williams, M

2007-01-01

Thyroid dysfunction as an important cardiovascular risk factor, is not well characterized among cardiology patients of Georgia. Further, a consensus has not been reached about the relationships between thyroid function markers and plasma lipids. We investigated these risk factors among 250 cardiology patients admitted to the Emergency Cardiology Center. A cross sectional study was conducted using in-person interviews, medical records, physical exams and laboratory studies. Thyroid stimulating hormone, free thyroxine 3, free thyroxine 4 and plasma lipids were measured using standardized assays. Overall, thyroid dysfunction was detected among 28.6% of the study population (19.5% males and 39.6% females). Overt hypo- and hyperthyroidism were present among 12.4% and 6.0% of patients, while, subclinical hypo- and hyperthyroidism were present among 2.8% and 6.4% of patients respectively. Both clinical and subclinical hypothyroidism were associated with elevated total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) concentrations (p-values for trend <0.005). Further, TC and LDL-C were highly correlated with thyroid function markers (all p-values <0.000). Triglycerides and high-density lipoprotein cholesterol concentrations were not associated with thyroid function status. Hyperthyroidism was not associated with plasma lipid variation. thyroid dysfunction was prevalent among cardiology patients in Georgia. Hypothyroidism was associated with elevated TC and LDL-C concentrations. Future studies that examine the clinical relevance of observed differences in lipid profiles among this population are needed.

Thyroid cell lines in research on goitrogenesis.

PubMed

Gerber, H; Peter, H J; Asmis, L; Studer, H

1991-12-01

Thyroid cell lines have contributed a lot to the understanding of goitrogenesis. The cell lines mostly used in thyroid research are briefly discussed, namely the rat thyroid cell lines FRTL and FRTL-5, the porcine thyroid cell lines PORTHOS and ARTHOS, The sheep thyroid cell lines OVNIS 5H and 6H, the cat thyroid cell lines PETCAT 1 to 4 and ROMCAT, and the human thyroid cell lines FTC-133 and HTh 74. Chinese hamster ovary (CHO) cells and COS-7 cells, stably transfected with TSH receptor cDNA and expressing a functional TSH receptor, are discussed as examples for non-thyroidal cells, transfected with thyroid genes.

THYROID HORMONE DISRUPTION: FROM KINETICS TO DYNAMICS.

EPA Science Inventory

A wide range of chemicals with diverse structures act as thyroid disrupting chemicals (TDCs). Broadly defined, TDCs are chemicals that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormones (THs), or change circulating or t...

Review and hypothesis: does Graves' disease develop in non-human great apes?

PubMed

McLachlan, Sandra M; Alpi, Kristine; Rapoport, Basil

2011-12-01

Graves' disease, caused by stimulatory thyrotropin receptor (TSHR) autoantibodies, has not been observed in animals. In contrast, Hashimoto's thyroiditis develops in chickens, rats, mice, dogs, and marmosets. Attempts to induce an immune response in mice to the luteinizing-hormone receptor suggested that autoantigen glycosylation was one parameter involved in breaking self-tolerance. Over evolution, TSHR glycosylation increased from three asparagine-linked-glycans (N-glycans) in fish to six N-glycans in humans and great apes. All other placental mammals lack one N-glycan in the shed TSHR A-subunit, the primary Graves' disease autoantigen. We hypothesized that (a) lesser TSHR A-subunit glycosylation reduces immunogenicity, accounting for the absence of Graves' disease in most placental mammals; (b) due to human-like A-subunit glycosylation, Graves' disease might arise in great apes. Here, we review and analyze the literature on this subject and report the results of a survey of veterinarians at primate centers and zoos in North America. Previous experimental data from induced TSHR antibodies in mice support a role for A-subunit glycosylation in breaking self-tolerance. An extensive search of the great-ape literature revealed five reports of noncongenital thyroid dysfunction, four with hypothyroidism and one with hyperthyroidism. The latter was a gorilla who was treated with anti-thyroid drugs but is now deceased. Neither serum nor thyroid tissue from this gorilla were available for analysis. The survey of veterinarians revealed that none of the 979 chimpanzees in primate research centers had a diagnosis of noncongenital thyroid dysfunction and among ∼1100 great apes (gorillas, orangutans, and chimpanzees) in U.S. zoos, only three were hypothyroid, and none were hyperthyroid. Graves' disease appears to be either very rare or does not occur in great apes based on the literature and a survey of veterinarians. Although the available data do not advance our hypothesis, there is a paucity of information regarding thyroid function tests and thyroid autoantibodies in the great apes In addition, these primates may be protected against TSHR autoimmunity by the absence of genetic polymorphisms and putative environmental triggers. Finally, larger numbers of great apes need to be followed, and tests of thyroid function and thyroid autoantibodies be performed, to confirm that spontaneous Graves' disease is restricted to humans.

[Evaluation of salivary gland function in women with autoimmune thyroid diseases].

PubMed

Koczor-Rozmus, Aleksandra; Zwirska-Korczala, Krystyna; Sadlak-Nowicka, Jadwiga; Ilewicz, Leşzek; Mayer-Parka, Danuta; Wierucka-Młynarczyk, Beata

2003-01-01

The function of the salivary glands is regulated by nervous system which influences salivary circulation. Moreover the volume of secreted saliva depends on the humoral agents, including thyroid hormones. The aim of the study was to determine the quantity of the secreted mixed resting and stimulated saliva in women with autoimmune thyroid diseases (AITD) depending on the function of the thyroid gland (hyperthyroidism, hypothyroidism and euthyroidism). The association between thyroid antibody concentrations (TPO-Ab, Tg-Ab, TR-Ab) and volume of secreted saliva was also examined. Studies were performed in 106 women suffering from AITD and 15 healthy volunteers. In hyperthyroid women there was a decrease in volumes of resting (57.14%) and stimulated (89.29%) saliva. Similarly, a decrease in secretion of resting (75%) and stimulated (66.67%) saliva was shown in hypothyroid women. In euthyroid patients with AITD there was a partial normalisation of salivary glands function. The negative correlation between concentrations of TPO-Ab, Tg-Ab and the volume of resting and stimulated saliva was found. In conclusion, AITD may be associated with disturbances in salivary secretion which depends on thyroid hormones production. It can be suggested that autoimmunological processes within salivary glands may influence their function.

[MORPHO-FUNCTIONAL CHARACTERISTIC OF THE THYROID GLAND AFTER ADMINISTRATION OF COPPER NANOPARTICLES].

PubMed

Polyakova, V S; Sizova, Ye A; Miroshnikov, S A; Notova, S V; Zavaleyeva, S M

2015-01-01

The study was conducted on 15 male Wistar rats, which were injected intramuscularly with copper nanoparticle lyosols at a dose of 2.0 mg/kg body weight once a week for 3 months. Thyroid gland was removed 7 days after the last injection and was studied using histological, morphometric and immunohistochemical methods (demonstration of Ki-67 and caspase-3). Animals of the control group (n = 15) were administered distilled water at the same time intervals. It was found that after 1, 2, 3 and 4 injections of copper nanoparticles, the thyroid gland contained an increased number of large cyst-like follicles, while the average thyrocyte height of and the volume of their nuclei were reduced, which indicate a decline in hormone production. After 12 injections of copper nanoparticles, the hyperplastic thyroid gland demonstrated small follicles lined with columnar epithelium, which contained no or small amount of the colloid. The number of mitotically dividing thyrocytes was increased. Parafollicular cells demonstrated an apoptotic dominant. Morphological data suggest goitrogenic effect of multiple doses of copper nanopartides. The data received indicating the readiness of the thyroid cells to the programmed death and its possible depression (absence of signs of thyrocyte apoptosis) at different stages of the experiment confirm the modulating effect of copper on apoptosis.

A tiered approach to evaluate an iodine recycling inhibition ...

EPA Pesticide Factsheets

The enzyme iodotyrosine deiodinase (dehalogenase, IYD) catalyzes iodide recycling and promotes iodide retention in thyroid follicular cells. Loss of function or chemical inhibition of IYD reduces thyroid hormone synthesis, which leads to insufficiency in tissues and subsequent negative developmental consequences. Iodide recycling by IYD is especially critical for low iodine diets and low iodine environments, including most freshwater ecosystems. We developed a putative adverse outcome pathway for IYD inhibition in amphibians and evaluated IYD inhibition with a tiered approach: 1) development of an in vitro IYD enzyme inhibition assay for chemical screening of compounds of interest to the US EPA, 2) ex vivo thyroid culture to establish thyroglobulin iodination as a biomarker of IYD inhibition, and 3) in vivo bioassays to characterize an organismal adverse outcome and test essentiality of IYD activity. An in vitro colorimetric assay was developed to measure activity of recombinant human IYD enzyme in a 96-well format, establishing the feasibility of medium to high throughput screening of chemicals for IYD inhibition. In ex vivo thyroid culture studies, thyroxine (T4), monoiodotyrosine (MIT), and diiodotyrosine (DIT) were quantified in individual thyroid glands and the media using a ultrahigh performance LC-MS/MS. In vivo exposure of developing Xenopus laevis to a suspected IYD inhibitor (3-L-nitro-tyrosine) resulted in markedly delayed metamorphosis and glandular

Iodine deficiency and thyroid disorders.

PubMed

Zimmermann, Michael B; Boelaert, Kristien

2015-04-01

Iodine deficiency early in life impairs cognition and growth, but iodine status is also a key determinant of thyroid disorders in adults. Severe iodine deficiency causes goitre and hypothyroidism because, despite an increase in thyroid activity to maximise iodine uptake and recycling in this setting, iodine concentrations are still too low to enable production of thyroid hormone. In mild-to-moderate iodine deficiency, increased thyroid activity can compensate for low iodine intake and maintain euthyroidism in most individuals, but at a price: chronic thyroid stimulation results in an increase in the prevalence of toxic nodular goitre and hyperthyroidism in populations. This high prevalence of nodular autonomy usually results in a further increase in the prevalence of hyperthyroidism if iodine intake is subsequently increased by salt iodisation. However, this increase is transient because iodine sufficiency normalises thyroid activity which, in the long term, reduces nodular autonomy. Increased iodine intake in an iodine-deficient population is associated with a small increase in the prevalence of subclinical hypothyroidism and thyroid autoimmunity; whether these increases are also transient is unclear. Variations in population iodine intake do not affect risk for Graves' disease or thyroid cancer, but correction of iodine deficiency might shift thyroid cancer subtypes toward less malignant forms. Thus, optimisation of population iodine intake is an important component of preventive health care to reduce the prevalence of thyroid disorders. Copyright © 2015 Elsevier Ltd. All rights reserved.

Morphological, diagnostic and surgical features of ectopic thyroid gland: a review of literature.

PubMed

Guerra, Germano; Cinelli, Mariapia; Mesolella, Massimo; Tafuri, Domenico; Rocca, Aldo; Amato, Bruno; Rengo, Sandro; Testa, Domenico

2014-01-01

Ectopic thyroid tissue remains a rare developmental abnormality involving defective or aberrant embryogenesis of the thyroid gland during its passage from the floor of the primitive foregut to its usual final position in pre-tracheal region of the neck. Its specific prevalence accounts about 1 case per 100.000-300.000 persons and one in 4.000-8.000 patients with thyroid disease show this condition. The cause of this defect is not fully known. Despite genetic factors have been associated with thyroid gland morphogenesis and differentiation, just recently some mutation has been associated with human thyroid ectopy. Lingual region in the most common site of thyroid ectopy but ectopic thyroid tissue were found in other head and neck locations. Nevertheless, aberrant ectopic thyroid tissue has been found in other places distant from the neck region. Ectopic tissue is affected by different pathological changes that occur in the normal eutopic thyroid. Patients may present insidiously or as an emergency. Diagnostic management of thyroid ectopy is performed by radionuclide thyroid imaging, ultrasonography, CT scan, MRI, biopsy and thyroid function tests. Asymptomatic euthyroid patients with ectopic thyroid do not usually require therapy but are kept under observation. For those with symptoms, treatment depends on size of the gland, nature of symptoms, thyroid function status and histological findings. Surgical excision is often required as treatment for this condition. Copyright © 2014 Surgical Associates Ltd. Published by Elsevier Ltd. All rights reserved.

Thyroid Disorders Overview

MedlinePlus

... state, with many body systems developing abnormal function. Hypothyroidism Too little thyroid hormone from an underactive thyroid gland is called hypothyroidism. In hypothyroidism, the body's metabolism is slowed. Several ...

[Morphological changes in the thyroid gland of rats during various phases of the estral cycle].

PubMed

Pliner, L I; Ledovskaia, S M

1975-08-01

The functional state of the thyroid gland and the concentration of thyroid hormones in the peripheral blood were studied in 20 mature female albino rats during their estral cycle. Evaluation of the thyroid functional state was made according to data of histological, morphological (the diameter of folliculi, the height of the thyroid epithelium) and histochemical analysis (determination of NAD and NADP-dehydrogenase, succinatedehydrogenase, lactate dehydrogenase, peroxydase, acid and alkaline phosphatase) as well as biochemical determination of iodine bound with protein (IBP) in the blood plasma and investigation of the ratio of the parameters in question under conditions of the sex cycle. The cyclic changes of the morphological state of the thyroid gland attended by the phases of the estral cycle were revealed. The activation of the organ was observed in proestrus and estrus which was evidenced by high levels of activity of the enzymes under study, high concentration of IBP in the blood and increased height of thyreocytes. A decreased function of the thyroid parenchyma was observed at the period of metaestrus-diestrus.

THYROID DISRUPTING CHEMICALS: CHALLENGES IN ASSESSING NEUROTOXIC RISK FROM ENVIRONMENTAL MIXTURES.

EPA Science Inventory

Environmental contaminants are known to act as thyroid disrupting chemicals (TDCs). Broadly defined, TDCs are xenobiotics that alter the structure or function of the thyroid gland, alter regulatory enzymes associated with thyroid hormone (TH) homeostasis, or change circulating o...

Assessment of petroleum streams for thyroid toxicity.

PubMed

Fowles, Jeff R; Banton, Marcy I; Boogaard, Peter J; Ketelslegers, Hans B; Rohde, Arlean M

2016-07-08

The thyroid gland, and its associated endocrine hormones, is a growing area of interest in regulatory toxicology due to its important role in metabolism, growth and development. This report presents a review of the toxicology data on chemically complex petroleum streams for thyroid hormone effects. Toxicological summaries and studies from all available published and un-published sources were considered, drawing upon the European REACH regulatory submissions for 19 petroleum streams, with in depth review of 11 individual study reports and 31 published papers on related products or environmental settings. Findings relevant to thyroid pathology or thyroid hormone homeostasis were specifically sought, summarized, and discussed. A total of 349 studies of 28-days or longer duration were considered in the review, including data on mice, rats, rabbits, dogs, humans, and fish. The thyroid was almost invariably not a target organ in these studies. Three rodent studies did find thyroid effects; one on a jet fuel product (JP-8), and two studies on a heavy fuel oil product (F-179). The JP-8 product differs from other fuels due to the presence of additives, and the finding of reduced T4 levels in mice in the study occurred at a dose that is above that expected to occur in environmental settings (e.g. 2000mg/kg). The finding for F-179 involved thyroid inflammation at 10-55mg/kg that co-occurred with liver pathology in rats, indicating a possible secondary effect with questionable relevance to humans. In the few cases where findings did occur, the polycyclic aromatic hydrocarbon (PAH) content was higher than in related substances, and, in support of one possible adverse outcome pathway, one in-vitro study reported reduced thyroid peroxidase (TPO) activity with exposure to some PAH compounds (pyrene, benzo(k)fluoranthene, and benzo(e)pyrene). However, it could not be determined from the data available for this review, whether these specific PAH compounds were substantially higher in the JP-8 or F-179 products than in studies in which thyroid effects were not observed. Thus, a few products may carry a weak potential to affect the thyroid at high doses in rodents, possibly through secondary effects on the rodent liver or possibly through a pathway involving the inhibition of TPO by specific members of the PAH family. Human epidemiology evidence found weak and inconsistent effects on the thyroid but without identification of specific chemicals involved. Two studies in petroleum workers, which found a lower rate of morbidity and mortality overall, reported a statistically significant increase in thyroid cancer, but the small number of cases could not exclude confounding variables as possible explanations for the statistical findings. Overall, the available data indicates a low potential for thyroid hormone effects from exposure to petroleum streams, especially when the aromatic content is low. Because regulatory studies for most chemicals do not include detailed thyroid function or receptor studies, it remains possible that subclinical effects on this system may exist that were not detectable using conventional pathology or hormone measurements. Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Role of maternal thyroid hormones in the developing neocortex and during human evolution

PubMed Central

Stenzel, Denise; Huttner, Wieland B.

2013-01-01

The importance of thyroid hormones during brain development has been appreciated for many decades. In humans, low levels of circulating maternal thyroid hormones, e.g., caused by maternal hypothyroidism or lack of iodine in diet, results in a wide spectrum of severe neurological defects, including neurological cretinism characterized by profound neurologic impairment and mental retardation, underlining the importance of the maternal thyroid hormone contribution. In fact, iodine intake, which is essential for thyroid hormone production in the thyroid gland, has been related to the expansion of the brain, associated with the increased cognitive capacities during human evolution. Because thyroid hormones regulate transcriptional activity of target genes via their nuclear thyroid hormone receptors (THRs), even mild and transient changes in maternal thyroid hormone levels can directly affect and alter the gene expression profile, and thus disturb fetal brain development. Here we summarize how thyroid hormones may have influenced human brain evolution through the adaptation to new habitats, concomitant with changes in diet and, therefore, iodine intake. Further, we review the current picture we gained from experimental studies in rodents on the function of maternal thyroid hormones during developmental neurogenesis. We aim to evaluate the effects of maternal thyroid hormone deficiency as well as lack of THRs and transporters on brain development and function, shedding light on the cellular behavior conducted by thyroid hormones. PMID:23882187

Thyroid Function Variations Within the Reference Range Do Not Affect Quality of Life, Mood, or Cognitive Function in Community-Dwelling Older Men.

PubMed

Samuels, Mary H; Kaimal, Rajani; Waring, Avantika; Fink, Howard A; Yaffe, Kristine; Hoffman, Andrew R; Orwoll, Eric; Bauer, Douglas

2016-09-01

Variations in thyroid function within the laboratory reference range have been associated with a number of clinical outcomes. However, quality of life, mood, and cognitive function have not been extensively studied, and it is not clear whether mild variations in thyroid function have major effects on these neurocognitive outcomes. Data were analyzed from the Osteoporotic Fractures in Men (MrOS) Study, a cohort of community-dwelling men aged 65 years and older in the United States. A total of 539 participants who were not taking thyroid medications and had age-adjusted TSH levels within the reference range underwent detailed testing of quality of life, mood, and cognitive function at baseline. The same quality of life, mood, and cognitive outcomes were measured again in 193 of the men after a mean follow-up of 6 years. Outcomes were analyzed using thyrotropin (TSH) and free thyroxine (FT4) levels as continuous independent variables, adjusting for relevant covariates. At baseline, there were no associations between TSH or FT4 levels and measures of quality of life, mood, or cognition in the 539 euthyroid men. Baseline thyroid function did not predict changes in these outcomes over a mean of 6 years in the 193 men in the longitudinal analysis. Variations in thyroid function within the age-adjusted laboratory reference range are not associated with variations in quality of life, mood, or cognitive function in community-dwelling older men.

Transient hypothyroidism in infants born to mothers with chronic thyroiditis--a nationwide study of twenty-three cases. The Transient Hypothyroidism Study Group.

PubMed

Matsuura, N; Konishi, J

1990-06-01

To define the difference in prognosis and the clinical features of transient neonatal hypothyroidism in infants born to mothers with chronic thyroiditis, we conducted a nationwide study of this condition. Sixteen mothers with chronic thyroiditis and twenty-three of their offspring with transient hypothyroidism were registered and reported in this paper. Five (group A) of twenty-two live infants showed physical, mental and/or psychomotor developmental delay (IQ below 80). No significant difference between TSH-binding inhibitor immunoglobulin (TBII) or thyroid-stimulation blocking antibody (TSBAb) activities in groups A and B (normal development) were noted. Moreover, there was no significant difference in thyroid function in the newborn period, ages at the start of thyroid medication or the dose and duration of treatment in the two groups. A striking difference observed between the two groups was the thyroid function of their mothers during pregnancy. In group A, four mothers were hypothyroid during pregnancy, and another mother discontinued thyroid medication in the last trimester and her baby was most delayed at the start thyroid medication. On the other hand, the mothers of only two of seventeen live cases in group B had mild hypothyroidism during pregnancy. There were two sets of siblings whose mother received inadequate treatment during the first pregnancy and adequate treatment during the second pregnancy. The psychomotor, physical and mental developmental delay were observed in their first babies. These findings suggested that maternal thyroid function during pregnancy might be an important factor in the prognosis of infants born to mothers with chronic thyroiditis.

Fetal Thyroid Function, Birth Weight, and in Utero Exposure to Fine Particle Air Pollution: A Birth Cohort Study

PubMed Central

Janssen, Bram G.; Saenen, Nelly D.; Roels, Harry A.; Madhloum, Narjes; Gyselaers, Wilfried; Lefebvre, Wouter; Penders, Joris; Vanpoucke, Charlotte; Vrijens, Karen; Nawrot, Tim S.

2016-01-01

Background: Thyroid hormones are critical for fetal development and growth. Whether prenatal exposure to fine particle air pollution (≤ 2.5 μm; PM2.5) affects fetal thyroid function and what the impact is on birth weight in normal healthy pregnancies have not been studied yet. Objectives: We studied the impact of third-trimester PM2.5 exposure on fetal and maternal thyroid hormones and their mediating role on birth weight. Methods: We measured the levels of free thyroid hormones (FT3, FT4) and thyroid-stimulating hormone (TSH) in cord blood (n = 499) and maternal blood (n = 431) collected after delivery from mother–child pairs enrolled between February 2010 and June 2014 in the ENVIRONAGE birth cohort with catchment area in the province of Limburg, Belgium. Results: An interquartile range (IQR) increment (8.2 μg/m3) in third-trimester PM2.5 exposure was inversely associated with cord blood TSH levels (–11.6%; 95% CI: –21.8, –0.1) and the FT4/FT3 ratio (–62.7%; 95% CI: –91.6, –33.8). A 10th–90th percentile decrease in cord blood FT4 levels was associated with a 56 g decrease in mean birth weight (95% CI: –90, –23). Assuming causality, we estimated that cord blood FT4 mediated 21% (–19 g; 95% CI: –37, –1) of the estimated effect of an IQR increment in third-trimester PM2.5 exposure on birth weight. Third-trimester PM2.5 exposure was inversely but not significantly associated with maternal blood FT4 levels collected 1 day after delivery (–4.0%, 95% CI: –8.0, 0.2 for an IQR increment in third-trimester PM2.5). Conclusions: In our study population of normal healthy pregnancies, third-trimester exposure to PM2.5 air pollution was associated with differences in fetal thyroid hormone levels that may contribute to reduced birth weight. Additional research is needed to confirm our findings in other populations and to evaluate potential consequences later in life. Citation: Janssen BG, Saenen ND, Roels HA, Madhloum N, Gyselaers W, Lefebvre W, Penders J, Vanpoucke C, Vrijens K, Nawrot TS. 2017. Fetal thyroid function, birth weight, and in utero exposure to fine particle air pollution: a birth cohort study. Environ Health Perspect 125:699–705; http://dx.doi.org/10.1289/EHP508 PMID:27623605

Effects of Sample Handling and Analytical Procedures on Thyroid Hormone Concentrations in Pregnant Women's Plasma.

PubMed

Villanger, Gro Dehli; Learner, Emily; Longnecker, Matthew P; Ask, Helga; Aase, Heidi; Zoeller, R Thomas; Knudsen, Gun P; Reichborn-Kjennerud, Ted; Zeiner, Pål; Engel, Stephanie M

2017-05-01

Maternal thyroid function is a critical mediator of fetal brain development. Pregnancy-related physiologic changes and handling conditions of blood samples may influence thyroid hormone biomarkers. We investigated the reliability of thyroid hormone biomarkers in plasma of pregnant women under various handling conditions. We enrolled 17 pregnant women; collected serum and plasma were immediately frozen. Additional plasma aliquots were subjected to different handling conditions before the analysis of thyroid biomarkers: storage at room temperature for 24 or 48 hours before freezing and an extra freeze-thaw cycle. We estimated free thyroid hormone indices in plasma based on T3 uptake. High correlations between plasma and serum (>0.94) and intraclass correlation coefficients for plasma handling conditions (0.96 to 1.00) indicated excellent reliability for all thyroid hormone biomarkers. Delayed freezing and freeze-thaw cycles did not affect reliability of biomarkers of thyroid function in plasma during pregnancy. See video abstract at, http://links.lww.com/EDE/B180.

High prevalence of iatrogenic hyperthyroidism in elderly patients with atrial fibrillation in an anticoagulation clinic.

PubMed

Krishnan, Sandeep Kumar; Dohrmann, Mary L; Brietzke, Stephen A; Fleming, David A; Flaker, Greg C

2011-01-01

In elderly patients with established atrial fibrillation (AF) who are receiving thyroid replacement, regular testing for thyroid function is often not performed, placing the patient at risk for iatrogenic hyperthyroidism. Of 215 patients followed in an anticoagulation clinic, 41 were receiving thyroid replacement and 15 of these were found to have hyperthyroidism. Eight had documented AF coincident with abnormal thyroid function. In addition, only 22 patients on thyroid replacement had an annual TSH. In conclusion, iatrogenic hyperthyroidism may frequently be missed in AF patients because of inadequate monitoring of serum TSH. Thyroid replacement is common in elderly patients with AF followed in an anticoagulation clinic. Laboratory evidence of hyperthyroidism occurred in 37%, usually in patients with higher doses of thyroid replacement, and often associated with AF. The frequency of iatrogenic hyperthyroidism may be underestimated in patients with AF since many patients who receive thyroid replacement therapy are not monitored regularly with serum TSH.

Free Thyroid Transfer: A Novel Procedure to Prevent Radiation-induced Hypothyroidism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harris, Jeffrey; Almarzouki, Hani; Department of Otolaryngology-Head and Neck Surgery, King Abdulaziz University, Jeddah

Purpose: The incidence of hypothyroidism after radiation therapy for head and neck cancer (HNC) has been found to be ≤53%. Medical treatment of hypothyroidism can be costly and difficult to titrate. The aim of the present study was to assess the feasibility of free thyroid transfer as a strategy for the prevention of radiation-induced damage to the thyroid gland during radiation therapy for HNC. Methods and Materials: A prospective feasibility study was performed involving 10 patients with a new diagnosis of advanced HNC undergoing ablative surgery, radial forearm free-tissue transfer reconstruction, and postoperative adjuvant radiation therapy. During the neck dissection,more » hemithyroid dissection was completed with preservation of the thyroid arterial and venous supply for implantation into the donor forearm site. All patients underwent a diagnostic thyroid technetium scan 6 weeks and 12 months postoperatively to examine the functional integrity of the transferred thyroid tissue. Results: Free thyroid transfer was executed in 9 of the 10 recruited patients with advanced HNC. The postoperative technetium scans demonstrated strong uptake of technetium at the forearm donor site at 6 weeks and 12 months for all 9 of the transplanted patients. Conclusions: The thyroid gland can be transferred as a microvascular free transfer with maintenance of function. This technique could represent a novel strategy for maintenance of thyroid function after head and neck irradiation.« less

Effect of estrogen therapy for 1 year on thyroid volume and thyroid nodules in postmenopausal women.

PubMed

Ceresini, Graziano; Milli, Bruna; Morganti, Simonetta; Maggio, Marcello; Bacchi-Modena, Alberto; Sgarabotto, Maria Paola; Chirico, Carla; Di Donato, Pietro; Campanati, Paolo; Valcavi, Roberto; Ceda, Gian Paolo; Braverman, Lewis E; Valenti, Giorgio

2008-01-01

Estrogen receptors are present in thyroid follicular cells in normal and neoplastic tissue. We evaluated changes in total thyroid volume and volume of thyroid nodules in postmenopausal women given either hormone therapy (HT) or no treatment in a 1-year observational follow-up. We studied 33 women receiving HT and 76 women receiving no treatment, comparing total thyroid volume, thyroid nodule volume, and serum concentrations of thyroid-stimulating hormone and estradiol at baseline and 1 year of follow-up. Serum thyroid-stimulating hormone concentrations were not different between groups either at baseline or at 1 year. Estradiol rose significantly in the HT group. The final percent changes in total thyroid volume were comparable between groups (HT, 1.59 +/- 2.56%; no treatment, 1.20 +/- 2.28%). At baseline, nodules were detected in 17 (51.5%) and 33 (43.4%) of women in the HT and no treatment groups, respectively, with no statistically significant difference between groups. The final number of nodules was unchanged or reduced in 88.2% and 81.1% and increased in 11.8% and 18.9% of women in the HT and no treatment groups, respectively, with no differences between groups. Baseline volumes of thyroid nodules were 0.8 +/- 0.4 and 1.4 +/- 0.4 mL in women in the HT and no treatment groups, respectively (P = 0.4). After 1 year the volume of thyroid nodules was unchanged or reduced in 47.1% and 52.8% and increased in 52.9% and 47.2% of women in the HT and no treatment groups, respectively, with no differences between groups. Estrogen administration for 1 year did not affect thyroid volume or the number and volume of thyroid nodules in postmenopausal women.

[Structural and functional status of the hypophyseal-thyroid system in prenatally irradiated children].

PubMed

Makiienko, T S; Pavliuk, V P; Pavliuk, I V; Mosiienko, A P

2001-01-01

In order to evaluate the morphologic-and-functional state of the hypophysis-thyroid system long after the Chernobyl accident we examined 1491 children from the northern territories of the Zhitomir region. Of these, 261 had not been in utero exposed to radioiodine, 1230 pediatric subjects proved to be postconception-exposed. In utero radioiodine has not been found to affect the thyroid size in any noticeable way. The degree of structural-and-functional indices for the thyreostat system in prenatally irradiated children depends on the stage of the thyroid development just when there happened to be an exposure to radioiodine.

Marine-Lenhart syndrome in two adolescents, including one with thyroid cancer: a case series and review of the literature.

PubMed

Sharma, Animesh

2017-11-27

The coexistence of functional thyroid nodules and Graves' disease (GD) is a rare condition known as Marine-Lenhart syndrome. Thyroid cancer has been described in several adults, but never in children, with Marine-Lenhart syndrome. This paper discusses the challenges in diagnosis and the unique management of this condition in children, in the context of extant literature. In this case report, two adolescent female patients with Marine-Lenhart syndrome, aged 15 and 16 years, exhibited biochemical evidence of hyperthyroidism, and were found to have unilateral hyperfunctioning thyroid nodules via thyroid scintigraphy. Additionally, both patients showed elevated thyroid-stimulating immunoglobulins (TSI) and increased glandular activity, confirming background GD. Notably, one patient was also diagnosed with intranodular thyroid cancer upon preoperative examination. Both patients were treated via surgical resection. Summary and outlook: Diagnosis of Marine-Lenhart syndrome can be made in patients with functional thyroid nodules and increased glandular activity on thyroid scintigraphy. Standard doses of radioiodine ablation are not effective in the majority of patients and should be avoided due to the increased risk for thyroid cancer, making thyroidectomy the preferred treatment.

Thyroid dysfunctions of prematurity and their impacts on neurodevelopmental outcome.

PubMed

Chung, Mi Lim; Yoo, Han Wok; Kim, Ki-Soo; Lee, Byong Sop; Pi, Soo-Young; Lim, Gina; Kim, Ellen Ai-Rhan

2013-01-01

Thyroid dysfunction is very common and is associated with neurodevelopmental impairments in preterm infants. This study was conducted to determine the incidence and natural course of various thyroid dysfunctions and their impacts on neurodevelopmental outcomes among premature infants. A total of 177 infants were enrolled who were born at <34 weeks or whose birth weight was <1500 g and who underwent repeat thyroid function tests. We analyzed how various thyroid dysfunctions affected neurodevelopmental outcomes at 18 months of corrected age. Thyroid dysfunction was noted in 88 infants. Hypothyroxinemia was observed in 23 infants, and their thyroid function was influenced by variable clinical factors. Free T4 levels were all normalized without thyroxine medication, and neurodevelopmental outcomes were not affected. In contrast, hyperthyrotropinemia was not associated with other clinical factors. Among 58 subjects who had hyperthyrotropinemia, only 31 infants showed normal thyroid-stimulating hormone (TSH) levels at follow-up tests. The remaining 27 infants had persistently high TSH levels, which significantly and poorly influenced the neurodevelopmental outcomes. Thyroid dysfunction is common among preterm infants. With the exception of persistent hyperthyrotropinemia, it generally does not affect neurodevelopmental outcomes. However, the beneficial effects of thyroid hormone therapy in patients with persistent hyperthyrotropinemia merits further study.

DIAGNOSTIC CRITERIA FOR PROLIFERATIVE THYROID LESIONS IN BONY FISHES

EPA Science Inventory

Thyroid proliferative lesions are rather common in bony fishes but disagreement exists in the fish pathology community concerning diagnostic criteria for hyperplastic versus neoplastic lesions. To simplify the diagnosis of proliferative thyroid lesions and to reduce confusion reg...

Fifteen-Year Follow-Up of Thyroid Status in Adults with Down Syndrome

ERIC Educational Resources Information Center

Prasher, V.; Ninan, S.; Haque, S.

2011-01-01

Background: The natural history of thyroid function in adults with Down syndrome is relatively unknown with limited long-term follow-up data. Method: This study investigated annual thyroid function tests in 200 adults with Down syndrome over a 15-year period. Results: For healthy adults with Down syndrome there is a gradual increase in thyroxine…

[Use of terahertz electromagnetic radiation at nitric oxide frequencies for the correction of thyroid functional state during stress].

PubMed

Kirichuk, V F; Tsymbal, A A

2010-01-01

The influence of terahertz electromagnetic radiation at nitric oxide frequencies (150.176-150.664 Ghz) on the functional activity of rat thyroid gland subjected to acute immobilization stress has been studied. It is shown that terahertz radiation totally normalizes thyroid activity in stressed animals within 30 min after application.

Phosphatidylinositide 3-kinase (PI3K) and PI3K-related kinase (PIKK) activity contributes to radioresistance in thyroid carcinomas.

PubMed

Burrows, Natalie; Williams, Joseph; Telfer, Brian A; Resch, Julia; Valentine, Helen R; Fitzmaurice, Richard J; Eustace, Amanda; Irlam, Joely; Rowling, Emily J; Hoang-Vu, Cuong; West, Catharine M; Brabant, Georg; Williams, Kaye J

2016-09-27

Anaplastic (ATC) and certain follicular thyroid-carcinomas (FTCs) are radioresistant. The Phosphatidylinositide 3-kinase (PI3K) pathway is commonly hyperactivated in thyroid-carcinomas. PI3K can modify the PI3K-related kinases (PIKKs) in response to radiation: How PIKKs interact with PI3K and contribute to radioresistance in thyroid-carcinomas is unknown. Further uncertainties exist in how these interactions function under the radioresistant hypoxic microenvironment. Under normoxia/anoxia, ATC (8505c) and FTC (FTC-133) cells were irradiated, with PI3K-inhibition (via GDC-0941 and PTEN-reconstitution into PTEN-null FTC-133s) and effects on PIKK-activation, DNA-damage, clonogenic-survival and cell cycle, assessed. FTC-xenografts were treated with 5 × 2 Gy, ± 50 mg/kg GDC-0941 (twice-daily; orally) for 14 days and PIKK-activation and tumour-growth assessed. PIKK-expression was additionally assessed in 12 human papillary thyroid-carcinomas, 13 FTCs and 12 ATCs. GDC-0941 inhibited radiation-induced activation of Ataxia-telangiectasia mutated (ATM), ATM-and Rad3-related (ATR) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Inhibition of ATM and DNA-PKcs was PI3K-dependent, since activation was reduced in PTEN-reconstituted FTC-133s. Inhibition of PIKK-activation was greater under anoxia: Consequently, whilst DNA-damage was increased and prolonged under both normoxia and anoxia, PI3K-inhibition only reduced clonogenic-survival under anoxia. GDC-0941 abrogated radiation-induced cell cycle arrest, an effect most likely linked to the marked inhibition of ATR-activation. Importantly, GDC-0941 inhibited radiation-induced PIKK-activation in FTC-xenografts leading to a significant increase in time taken for tumours to triple in size: 26.5 ± 5 days (radiation-alone) versus 31.5 ± 5 days (dual-treatment). PIKKs were highly expressed across human thyroid-carcinoma classifications, with ATM scoring consistently lower. Interestingly, some loss of ATM and DNA-PKcs was observed. These data provide new insight into the mechanisms of hypoxia-associated radioresistance in thyroid-carcinoma.

Phosphatidylinositide 3-kinase (PI3K) and PI3K-related kinase (PIKK) activity contributes to radioresistance in thyroid carcinomas

PubMed Central

Burrows, Natalie; Williams, Joseph; Telfer, Brian A; Resch, Julia; Valentine, Helen R; Fitzmaurice, Richard J; Eustace, Amanda; Irlam, Joely; Rowling, Emily J; Hoang-Vu, Cuong; West, Catharine M; Brabant, Georg; Williams, Kaye J

2016-01-01

Anaplastic (ATC) and certain follicular thyroid-carcinomas (FTCs) are radioresistant. The Phosphatidylinositide 3-kinase (PI3K) pathway is commonly hyperactivated in thyroid-carcinomas. PI3K can modify the PI3K-related kinases (PIKKs) in response to radiation: How PIKKs interact with PI3K and contribute to radioresistance in thyroid-carcinomas is unknown. Further uncertainties exist in how these interactions function under the radioresistant hypoxic microenvironment. Under normoxia/anoxia, ATC (8505c) and FTC (FTC-133) cells were irradiated, with PI3K-inhibition (via GDC-0941 and PTEN-reconstitution into PTEN-null FTC-133s) and effects on PIKK-activation, DNA-damage, clonogenic-survival and cell cycle, assessed. FTC-xenografts were treated with 5 × 2 Gy, ± 50 mg/kg GDC-0941 (twice-daily; orally) for 14 days and PIKK-activation and tumour-growth assessed. PIKK-expression was additionally assessed in 12 human papillary thyroid-carcinomas, 13 FTCs and 12 ATCs. GDC-0941 inhibited radiation-induced activation of Ataxia-telangiectasia mutated (ATM), ATM-and Rad3-related (ATR) and DNA-dependent protein kinase catalytic subunit (DNA-PKcs). Inhibition of ATM and DNA-PKcs was PI3K-dependent, since activation was reduced in PTEN-reconstituted FTC-133s. Inhibition of PIKK-activation was greater under anoxia: Consequently, whilst DNA-damage was increased and prolonged under both normoxia and anoxia, PI3K-inhibition only reduced clonogenic-survival under anoxia. GDC-0941 abrogated radiation-induced cell cycle arrest, an effect most likely linked to the marked inhibition of ATR-activation. Importantly, GDC-0941 inhibited radiation-induced PIKK-activation in FTC-xenografts leading to a significant increase in time taken for tumours to triple in size: 26.5 ± 5 days (radiation-alone) versus 31.5 ± 5 days (dual-treatment). PIKKs were highly expressed across human thyroid-carcinoma classifications, with ATM scoring consistently lower. Interestingly, some loss of ATM and DNA-PKcs was observed. These data provide new insight into the mechanisms of hypoxia-associated radioresistance in thyroid-carcinoma. PMID:27527858

Subclinical hypothyroidism: Should we treat?

PubMed

Redford, Christopher; Vaidya, Bijay

2017-06-01

Subclinical hypothyroidism (also known as compensated hypothyroidism or mild hypothyroidism) is a condition associated with a raised serum concentration of thyroid stimulating hormone (TSH) but a normal serum free thyroxine (FT4). It is common, affecting about 10% of women above the age of 55 years. Autoimmunity is the commonest cause of subclinical hypothyroidism. About 2.5% of patients with subclinical hypothyroidism progress to clinically overt hypothyroidism each year; the rate of progression is higher in patients with thyroid autoantibodies and higher thyroid stimulating hormone levels. However, thyroid function normalises spontaneously in up to 40% cases. Only a small minority of patients with subclinical hypothyroidism have symptoms, and the evidence to support that levothyroxine ameliorate the symptoms in these patients is weak. Subclinical hypothyroidism in younger patients (<65 years) is associated with an increased risk of coronary heart disease, heart failure and cerebrovascular disease. The risk increases with increasing levels of thyroid stimulating hormone, and is particularly high in patients with TSH levels ≥10.0 mu/L. There is lack of evidence from randomised controlled trials as to whether levothyroxine treatment can prevent these risks, although a large observational study of the UK general practice research database has shown that levothyroxine may reduce the risk of coronary heart disease in younger patients (<70 years). Therefore, the decision whether to treat or not to treat subclinical hypothyroidism should be made after careful consideration of the patient's age, the presence of symptoms, the presence of thyroid antibodies and other risk factors such as cardiovascular disease.

Thyroid function testing in elephant seals in health and disease.

PubMed

Yochem, Pamela K; Gulland, Frances M D; Stewart, Brent S; Haulena, Martin; Mazet, Jonna A K; Boyce, Walter M

2008-02-01

Northern Elephant Seal Skin Disease (NESSD) is a severe, ulcerative, skin condition of unknown cause affecting primarily yearling northern elephant seals (Mirounga angustirostris); it has been associated with decreased levels of circulating thyroxine (T4) and triiodothyronine (T3). Abnormalities of the thyroid gland that result in decreased hormone levels (hypothyroidism) can result in hair loss, scaling and secondary skin infections. However, concurrent illness (including skin ailments) can suppress basal levels of thyroid hormones and mimic hypothyroidism; when this occurs in animals with normal thyroid glands it is called "sick euthyroid syndrome". The two conditions (true hypothyroidism vs. "sick euthyroid") can be distinguished in dogs by testing the response of the thyroid gland to exogenous thyrotropin (Thyroid Stimulating Hormone, TSH). To determine whether hypothyroidism is involved in the etiology of NESSD, we tested thyroid function of stranded yearling elephant seals in the following categories: healthy seals (rehabilitated and ready for release; N=9), seals suffering from NESSD (N=16) and seals with other illnesses (e.g., lungworm pneumonia; N=10). Levels of T4 increased significantly for all three categories of elephant seals following TSH stimulation, suggesting that seals with NESSD are "sick euthyroid" and that the disease is not associated with abnormal thyroid gland function.

Thyroid function changes related to use of iodinated water in the U.S. Space Program.

PubMed

McMonigal, K A; Braverman, L E; Dunn, J T; Stanbury, J B; Wear, M L; Hamm, P B; Sauer, R L; Billica, R D; Pool, S L

2000-11-01

The National Aeronautics and Space Administration (NASA) has used iodination as a method of microbial disinfection of potable water systems in U.S. spacecraft and long-duration habitability modules. A review of thyroid function tests of NASA astronauts who had consumed iodinated water during spaceflight was conducted. Thyroid function tests of all past and present astronauts were reviewed. Medical records of astronauts with a diagnosis of thyroid disease were reviewed. Iodine consumption by space crews from water and food was determined. Serum thyroid-stimulating hormone (TSH) and urinary iodine excretion from space crews were measured following modification of the Space Shuttle potable water system to remove most of the iodine. Mean TSH significantly increased in 134 astronauts who had consumed iodinated water during spaceflight. Serum TSH, and urine iodine levels of Space Shuttle crewmembers who flew following modification of the potable water supply system to remove iodine did not show a statistically significant change. There was no evidence supporting association between clinical thyroid disease and the number of spaceflights, amount of iodine consumed, or duration of iodine exposure. It is suggested that pharmacological doses of iodine consumed by astronauts transiently decrease thyroid function, as reflected by elevated serum TSH values. Although adverse effects of excess iodine consumption in susceptible individuals are well documented, exposure to high doses of iodine during spaceflight did not result in a statistically significant increase in long-term thyroid disease in the astronaut population.

Rapid Improvement of thyroid storm-related hemodynamic collapse by aggressive anti-thyroid therapy including steroid pulse: A case report.

PubMed

Kiriyama, Hiroyuki; Amiya, Eisuke; Hatano, Masaru; Hosoya, Yumiko; Maki, Hisataka; Nitta, Daisuke; Saito, Akihito; Shiraishi, Yasuyuki; Minatsuki, Shun; Sato, Tatsuyuki; Murakami, Haruka; Uehara, Masae; Manaka, Katsunori; Makita, Noriko; Watanabe, Masafumi; Komuro, Issei

2017-06-01

Heart failure is relatively common in patients with hyperthyroidism, but thyrotoxic cardiomyopathy with poor left ventricular (LV) systolic function is very rare. We experienced a representative case of a patient who presented with severe LV dysfunction related to thyroid storm and needed extracorporeal membrane oxygenation (ECMO) temporally. Thyrotoxic cardiomyopathy. Aggressive antithyroid therapy, including steroid pulse to hyperthyroidism, leads to the dramatic improvement of cardiac function and she was successfully weaned from ECMO. The most outstanding feature of the current case was the rapid decrease of cardiac injury and improvement of cardiac function by strengthening antithyroid therapy, including steroid pulse, without thyroid hormone level normalization. In thyroid storm, various systemic inflammatory reactions have different time courses and among them, the cardiac phenotype emerges in most striking and critical ways.

Thyroid storm following radioactive iodine (RAI) therapy for pediatric graves disease.

PubMed

Rohrs, Henry J; Silverstein, Janet H; Weinstein, David A; Amdur, Robert J; Haller, Michael J

2014-01-01

Female, 11 FINAL DIAGNOSIS: Thyroid storm Symptoms: Diarrhea • tachycardia • tachypnea • tremor • wheezing - Clinical Procedure: - Specialty: - Rare disease. A growing number of pediatric endocrinologists treat Graves disease with radioactive iodine (RAI) therapy due to the typically definitive nature of I-131 therapy. Given the published benefits and perceived low risks of RAI when compared to surgery or long-term anti-thyroid medication, the trend towards therapy with RAI is likely to continue. Nevertheless, RAI is not without significant risk. An 11-year-old girl with newly diagnosed Graves disease received RAI for definitive treatment of her hyperthyroidism. Within 24 hours of receiving I-131, she developed increasing sleepiness and eventually became unresponsive. Upon arrival at the emergency department she had a tonic-clonic seizure and was diagnosed with thyroid storm. Despite best efforts to manage her hyperthyroidism, she suffered a stroke of the left cerebral hemisphere that left her with persistent neurological deficits. Although thyroid storm after thyroid ablation is rare, the significant morbidity and potential mortality of pediatric thyroid storm warrant further studies to determine if children with markedly elevated thyroid hormone concentrations at diagnosis should receive prolonged pretreatment with anti-thyroid drugs. While such an approach may reduce the efficacy of I-131 ablation, it can also reduce and hopefully eliminate the risk of post-ablative thyroid storm.

Incorporating thyroid markers in Down syndrome screening protocols.

PubMed

Dhaifalah, Ishraq; Salek, Tomas; Langova, Dagmar; Cuckle, Howard

2017-05-01

The article aimed to assess the benefit of incorporating maternal serum thyroid disease marker levels (thyroid-stimulating hormone and free thyroxine) into first trimester Down syndrome screening protocols. Statistical modelling was used to predict performance with and without the thyroid markers. Two protocols were considered: the combined test and the contingent cell-free DNA (cfDNA) test, where 15-40% women are selected for cfDNA because of increased risk based on combined test results. Published parameters were used for the combined test, cfDNA and the Down syndrome means for thyroid-stimulating hormone and free thyroxine; other parameters were derived from a series of 5230 women screened for both thyroid disease and Down syndrome. Combined test: For a fixed 85% detection rate, the predicted false positive rate was reduced from 5.3% to 3.6% with the addition of the thyroid markers. Contingent cfDNA test: For a fixed 95% detection rate, the proportion of women selected for cfDNA was reduced from 25.6% to 20.2%. When screening simultaneously for maternal thyroid disease and Down syndrome, thyroid marker levels should be used in the calculation of Down syndrome risk. The benefit is modest but can be achieved with no additional cost. © 2017 John Wiley & Sons, Ltd. © 2017 John Wiley & Sons, Ltd.

Lymphocyte function following radioiodine therapy in patients with thyroid carcinoma.

PubMed

Barsegian, V; Müller, S P; Horn, P A; Bockisch, A; Lindemann, M

2011-01-01

Since the nuclear disaster in Fukushima has raised great concern about the danger of radioactivity, we here addressed the question if the therapeutic use of iodine 131, the most frequently applied radionuclide, was harmful to immune function in patients. It was our aim to define for the first time in a clinical setting how radioiodine therapy alters anti-microbial immune responses. In 21 patients with thyroid carcinoma anti-microbial lymphocyte responses were assessed by lymphocyte transformation test and ELISpot - measuring lymphocyte proliferation and on a single cell level production of pro- and anti-inflammatory cytokines (interferon-γ and interleukin-10) - prior to therapy, at day 1 and day 7 post therapy. Proliferative lymphocyte responses and interferon-γ production after in vitro stimulation with microbial antigens were significantly (p < 0.05) increased at day 1 vs. pre therapy, and returned to pre therapy levels at day 7. On the contrary, at day 1 interleukin-10 production was significantly (p < 0.05) reduced. Thus, we observed a short-term increase in pro-inflammatory immune responses. However, T lymphocyte responses were in the range of healthy controls at all three time points. Thyroid carcinoma patients receiving radioiodine therapy do not display any sign of immunosuppression.

Serum cholesterol and triglyceride concentrations in diabetic patients with subclinical hypothyroidism.

PubMed

Díez, Juan J; Iglesias, Pedro

2014-10-01

To assess whether subclinical hypothyroidism is associated to elevations in serum cholesterol and triglyceride levels in patients with type 2 diabetes. From a total population of 1,112 patients with type 2 diabetes screened for thyroid dysfunction (thyrotropin measurement), a group of 325 patients with normal thyroid function and another group of 29 patients with subclinical hypothyroidism were selected. No patient had known dyslipidemia or was taking lipid lowering medication. Patients with subclinical hypothyroidism had serum levels of total cholesterol (4.88 ± 0.74 mmol/L), HDL cholesterol (1.37 ± 0.34 mmol/L), LDL cholesterol (2.94 ± 0.58 mmol/L), and triglycerides (1.05 [0.88-1.41] mmol/L) that did not significantly differ from those found in euthyroid patients (4.79 ± 0.83, 1.33 ± 0.36, 2.87 ± 0.76, and 1.11 [0.81-1.43] mmol/L, respectively). Multiple regression analysis showed no association between TSH and serum lipid levels. These results suggest that, in our population, there are no significant differences in serum cholesterol and triglyceride levels between diabetic patients with normal and reduced thyroid function. Copyright © 2013 SEEN. Published by Elsevier Espana. All rights reserved.

Thyroid Function Tests

MedlinePlus

... problem that is directly affecting the thyroid (primary hypothyroidism). The opposite situation, in which the TSH level ... making enough TSH to stimulate the thyroid (secondary hypothyroidism). In most healthy individuals, a normal TSH value ...

Effect of leaded glasses and thyroid shielding on cone beam CT radiation dose in an adult female phantom

PubMed Central

Goren, AD; Prins, RD; Dauer, LT; Quinn, B; Al-Najjar, A; Faber, RD; Patchell, G; Branets, I; Colosi, DC

2013-01-01

Objectives: This study aims to demonstrate the effectiveness of leaded glasses in reducing the lens of eye dose and of lead thyroid collars in reducing the dose to the thyroid gland of an adult female from dental cone beam CT (CBCT). The effect of collimation on the radiation dose in head organs is also examined. Methods: Dose measurements were conducted by placing optically stimulated luminescent dosemeters in an anthropomorphic female phantom. Eye lens dose was measured by placing a dosemeter on the anterior surface of the phantom eye location. All exposures were performed on one commercially available dental CBCT machine, using selected collimation and exposure techniques. Each scan technique was performed without any lead shielding and then repeated with lead shielding in place. To calculate the percent reduction from lead shielding, the dose measured with lead shielding was divided by the dose measured without lead shielding. The percent reduction from collimation was calculated by comparing the dose measured with collimation to the dose measured without collimation. Results: The dose to the internal eye for one of the scans without leaded glasses or thyroid shield was 0.450 cGy and with glasses and thyroid shield was 0.116 cGy (a 74% reduction). The reduction to the lens of the eye was from 0.396 cGy to 0.153 cGy (a 61% reduction). Without glasses or thyroid shield, the thyroid dose was 0.158 cGy; and when both glasses and shield were used, the thyroid dose was reduced to 0.091 cGy (a 42% reduction). Conclusions: Collimation alone reduced the dose to the brain by up to 91%, with a similar reduction in other organs. Based on these data, leaded glasses, thyroid collars and collimation minimize the dose to organs outside the field of view. PMID:23412460

Comparison of the symptoms of menopause and symptoms of thyroid disease in Japanese women aged 35-59 years.

PubMed

Oi, N; Ohi, K

2013-10-01

In this study, we surveyed thyroid function abnormalities and menopausal symptoms in young as well as in menopausal women. We conducted a random survey among outpatients at our facility from September 2008 to June 2011. The study included 853 women aged 35-59 years. We assessed the subjects according to the Simplified Menopause Index, menstrual status, thyroid hormone measurements (thyroid stimulating hormone, free thyroxine, free triiodothyronine), the presence of Hashimoto's disease antibodies (anti-thyroid peroxidase antibody or anti-thyroglobulin antibody), the presence of Grave's disease (anti-TSH receptor antibody), markers of thyroid tumor (high thyroglobulin), and thyroid ultrasonography studies. The data were analyzed by means of the statistical program JMP version 8.0. 'Facial flushing', 'sweating', and 'thyroid tumor' were all positively related with age and menstrual status. 'Breathlessness and palpitations' were positively related to Grave's disease. Moreover, 'sweating', 'irritability', and 'stiff shoulders, low back pain, and joint pain' were related to thyroid tumors. 'Insomnia' decreased with age. Patients with Hashimoto's disease were very rare because they were usually treated at other hospitals that specialize in thyroid disease. The symptoms of thyroid function abnormalities were shown to be very similar to menopausal symptoms and were found to occur in younger women before the onset of menopause. This study shows the need to differentiate menopausal symptoms from those of thyroid diseases.

Modulation of Sodium Iodide Symporter in Thyroid Cancer

PubMed Central

Lakshmanan, Aparna; Scarberry, Daniel

2015-01-01

Radioactive iodine (RAI) is a key therapeutic modality for thyroid cancer. Loss of RAI uptake in thyroid cancer inversely correlates with patient’s survival. In this review, we focus on the challenges encountered in delivering sufficient doses of I-131 to eradicate metastatic lesions without increasing the risk of unwanted side effects. Sodium iodide symporter (NIS) mediates iodide influx, and NIS expression and function can be selectively enhanced in thyroid cells by thyroid-stimulating hormone. We summarize our current knowledge of NIS modulation in normal and cancer thyroid cells, and we propose that several reagents evaluated in clinical trials for other diseases can be used to restore or further increase RAI accumulation in thyroid cancer. Once validated in preclinical mouse models and clinical trials, these reagents, mostly small-molecule inhibitors, can be readily translated into clinical practice. We review available genetically engineered mouse models of thyroid cancer in terms of their tumor development and progression as well as their thyroid function. These mice will not only provide important insights into the mechanisms underlying the loss of RAI uptake in thyroid tumors but will also serve as preclinical animal models to evaluate the efficacy of candidate reagents to selectively increase RAI uptake in thyroid cancers. Taken together, we anticipate that the optimal use of RAI in the clinical management of thyroid cancer is yet to come in the near future. PMID:25234361

A longitudinal study on the radiation-induced thyroid gland changes after external beam radiotherapy of nasopharyngeal carcinoma.

PubMed

Lin, Zhixiong; Wu, Vincent Wing-Cheung; Lin, Jing; Feng, Huiting; Chen, Longhua

2011-01-01

Radiation-induced thyroid disorders have been reported in radiotherapy of head and neck cancers. This study evaluated the radiation-induced damages to thyroid gland in patients with nasopharyngeal carcinoma (NPC). Forty-five patients with NPC treated by radiotherapy underwent baseline thyroid hormones (free triiodothyronine, free thyroxine [fT4], and thyrotropin [TSH]) examination and CT scan before radiotherapy. The volume of the thyroid gland was calculated by delineating the structure in the corresponding CT slices using the radiotherapy treatment planning system. The thyroid doses were estimated using the treatment planning system. Subsequent CT scans were conducted at 6, 12, and 18 months after radiotherapy, whereas the hormone levels were assessed at 3, 6, 12, and 18 months after radiotherapy. Trend lines of the volume and hormone level changes against time were plotted. The relationship between the dose and the change of thyroid volume and hormone levels were evaluated using the Pearson correlation test. An average of 20% thyroid volume reduction in the first 6 months and a further 8% shrinkage at 12 months after radiotherapy were observed. The volume reduction was dependent on the mean thyroid doses at 6, 12, and 18 months after radiotherapy (r = -0.399, -0.472, and -0.417, respectively). Serum free triiodothyronine and fT4 levels showed mild changes of <2.5% at 6 months, started to drop by 8.8% and 11.3%, respectively, at 12 months, and became stable at 18 months. The mean serum TSH level increased mildly at 6 months after radiotherapy and more steeply after 18 months. At 18 months after radiotherapy, 12 patients had primary hypothyroidism with an elevated serum TSH, in which 4 of them also presented with low serum fT4. There was a significant difference (p = 0.014) in the mean thyroid doses between patients with hypothyroidism and normal thyroid function. Radiotherapy for patients with NPC caused radiation-induced changes of the thyroid gland. The shrinkage of the gland was greatest in the first 6 months after radiotherapy, whereas the serum fT4 and TSH levels changed at 12 months. Radiation-induced changes were dependent on the mean dose to the gland. Therefore, measures to reduce the thyroid dose in radiotherapy should be considered.

[A longitudinal study regarding the gestational changes in iodine nutrition and thyroid function among pregnant women in the iodine deficient areas of Henan province].

PubMed

Yang, Jin; Zheng, Heming; Li, Xiaofeng; Ying, Huili

2015-01-01

To characterize the gestational changes of iodine nutrition and thyroid function and to explore the factors associated with the thyroid function in pregnant women. A longitudinal survey was conducted in 130 pregnant women in Luohe city of Henan province from October 2012 to May 2013. Samples of fasting blood and urine were collected in each trimester to test on thyroid function and urinary iodine. Data regarding social demography and lifestyle behavior were collected through questionnaire in the first trimester. The medians of urinary iodine (MUI) for pregnant women were 238.9, 150.8 and 306.4 µg/L in the first, second and third trimesters, respectively (P < 0.05). With the increase of gestational age, the level of free triiodothyronine (FT3) showed no significant change (P > 0.05) but the level of free thyroxine (FT4) decreased (P < 0.05), with the level of thyroid stimulating hormone (TSH) increased and then declined (P < 0.05). A U-shaped curve were seen between iodine nutrition and thyroid function. With the increase of iodine level, the level of TSH first increased and then decreased while the levels of FT3 and FT4 showed the opposite trend. The level of TSH was influenced by factors as education level, history of chronic diseases, history of CT and X-ray examination, and intake of pickled food etc. The level of FT4 was associated with residence (urban or rural), stressful events in the previous year, daily means of transportation, and the hours of sedentariness, working and sleeping. Significant differences were noticed in iodine nutrition and thyroid function of pregnant women during the three trimesters. It was essential to establish specific reference ranges for different trimesters. Thyroid functions of pregnant women seemed to be associated with iodine level and lifestyle.

Marginal iodide deficiency and thyroid function: dose-response analysis for quantitative pharmacokinetic modeling.

PubMed

Gilbert, M E; McLanahan, E D; Hedge, J; Crofton, K M; Fisher, J W; Valentín-Blasini, L; Blount, B C

2011-04-28

Severe iodine deficiency (ID) results in adverse health outcomes and remains a benchmark for understanding the effects of developmental hypothyroidism. The implications of marginal ID, however, remain less well known. The current study examined the relationship between graded levels of ID in rats and serum thyroid hormones, thyroid iodine content, and urinary iodide excretion. The goals of this study were to provide parametric and dose-response information for development of a quantitative model of the thyroid axis. Female Long Evans rats were fed casein-based diets containing varying iodine (I) concentrations for 8 weeks. Diets were created by adding 975, 200, 125, 25, or 0 μg/kg I to the base diet (~25 μg I/kg chow) to produce 5 nominal I levels, ranging from excess (basal+added I, Treatment 1: 1000 μg I/kg chow) to deficient (Treatment 5: 25 μg I/kg chow). Food intake and body weight were monitored throughout and on 2 consecutive days each week over the 8-week exposure period, animals were placed in metabolism cages to capture urine. Food, water intake, and body weight gain did not differ among treatment groups. Serum T4 was dose-dependently reduced relative to Treatment 1 with significant declines (19 and 48%) at the two lowest I groups, and no significant changes in serum T3 or TSH were detected. Increases in thyroid weight and decreases in thyroidal and urinary iodide content were observed as a function of decreasing I in the diet. Data were compared with predictions from a recently published biologically based dose-response (BBDR) model for ID. Relative to model predictions, female Long Evans rats under the conditions of this study appeared more resilient to low I intake. These results challenge existing models and provide essential information for development of quantitative BBDR models for ID during pregnancy and lactation. Published by Elsevier Ireland Ltd.

Non-invasive management of fetal goiter during maternal treatment of hyperthyroidism in Grave's disease.

PubMed

Lembet, Arda; Eroglu, Derya; Kinik, Sibel Tulgar; Gurakan, Berkan; Kuscu, Esra

2005-01-01

There is an increased risk of fetal goiter in patients who have a history of Grave's disease and undergo propylthiouracil (PTU) treatment during pregnancy. In this report, we describe a case of a fetal goiter detected by antenatal ultrasound at the 26th week of gestation in a mother treated with PTU for Grave's disease. A 32 x 38 x 20 mm fetal goiter was detected, each lobe measured 30 x 18 x 18 mm and estimated volume was 10 cm3. Subsequently, fetal thyroid function was assessed by umbilical fetal blood sampling. Cord blood showed elevated serum TSH (40.2 mU/l) and normal concentrations of free T4 (9.5 pmol/l) and free T3 (2.6 pmol/l). There were no other ultrasonographic signs of fetal hypothyroidism. Based on the above findings, the mother's PTU dosage was reduced to 50 mg daily from a total of 150 mg and weekly ultrasonographic examinations were performed. Six weeks after the initial ultrasound, a complete regression of the fetal goiter was noted. At the 34th week of gestation, the patient was delivered due to intrauterine growth restriction and oligohydramnios and gave birth to a male, weighing 1,920 g. The newborn thyroid was not palpable and thyroid ultrasonography was normal. Cord blood TSH was normal (8.4 mU/l) and free T4 was within lower normal limit (9.03 pmol/l). Ten days later, newborn thyroid function was normal and the baby did well afterwards. In conclusion, after the evaluation of fetal thyroid status, selected cases with fetal goiter can be initially managed without intrauterine treatment. (c) 2005 S. Karger AG, Basel

Deficiency in the manganese efflux transporter SLC30A10 induces severe hypothyroidism in mice.

PubMed

Hutchens, Steven; Liu, Chunyi; Jursa, Thomas; Shawlot, William; Chaffee, Beth K; Yin, Weiling; Gore, Andrea C; Aschner, Michael; Smith, Donald R; Mukhopadhyay, Somshuvra

2017-06-09

Manganese is an essential metal that becomes toxic at elevated levels. Loss-of-function mutations in SLC30A10, a cell-surface-localized manganese efflux transporter, cause a heritable manganese metabolism disorder resulting in elevated manganese levels and parkinsonian-like movement deficits. The underlying disease mechanisms are unclear; therefore, treatment is challenging. To understand the consequences of loss of SLC30A10 function at the organism level, we generated Slc30a10 knock-out mice. During early development, knock-outs were indistinguishable from controls. Surprisingly, however, after weaning and compared with controls, knock-out mice failed to gain weight, were smaller, and died prematurely (by ∼6-8 weeks of age). At 6 weeks, manganese levels in the brain, blood, and liver of the knock-outs were ∼20-60-fold higher than controls. Unexpectedly, histological analyses revealed that the brain and liver of the knock-outs were largely unaffected, but their thyroid exhibited extensive alterations. Because hypothyroidism leads to growth defects and premature death in mice, we assayed for changes in thyroid and pituitary hormones. At 6 weeks and compared with controls, the knock-outs had markedly reduced thyroxine levels (∼50-80%) and profoundly increased thyroid-stimulating hormone levels (∼800-1000-fold), indicating that Slc30a10 knock-out mice develop hypothyroidism. Importantly, a low-manganese diet produced lower tissue manganese levels in the knock-outs and rescued the phenotype, suggesting that manganese toxicity was the underlying cause. Our unanticipated discovery highlights the importance of determining the role of thyroid dysfunction in the onset and progression of manganese-induced disease and identifies Slc30a10 knock-out mice as a new model for studying thyroid biology. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Effects of environmental chemicals on fish thyroid function: Implications for fisheries and aquaculture in Australia.

PubMed

Nugegoda, Dayanthi; Kibria, Golam

2017-04-01

Numerous environmental stressors exert acute or chronic effects on the fish thyroid cascade. Such effects could be mediated via thyroidal alterations, imbalance of plasma T4 and T3 levels or damage to the structure of the thyroidal tissues (thyroid hypertrophy, hyperplasia). The thyroidal system is intricately linked to other endocrine systems in vertebrates including the control of reproduction. Disruption of fish thyroid function by environmental stressors has the potential to result in deleterious effects including the inhibition of sperm production, reduction in egg production, gonad development, ovarian growth, swimming activity, fertilisation and increase in larval mortality. Thyroid hormones play a major role in the development and growth of fish, particularly during their early life stages, thus, thyroid disruption by environmental stressors could inhibit the growth of fish larvae and juveniles in wild fish and cultured species, limit fish seed production and result in a decline in wild fisheries. This review highlights the effects of several environmental toxicants including PBDE, PCBs, PCDD and PCDF, PAH/oil, phthalates, metals, pesticides, mixed pollutants/chemicals, cyanide; and other stressors including acid (low pH) and ammonia, on fish thyroid function. Environmental sources of chemical stressors and appropriate water quality guidelines to protect the freshwater and marine species for the relevant pollutants are also discussed including (when available) the Australian guidelines (2000) and Canadian water quality guidelines (where Australian guidelines are not available). To date there has been no published research on the effects of anthropogenic environmental pollutants on the thyroid system of any native Australian fish species. However, the detection of high risk chemicals (notably PBDEs, PCBs, PAHs, metals and pesticides) in Australian waterways and Australian fish and shellfish implies that thyroid disruption of Australian wild fish and aquacultured species could occur. It is therefore imperative that the effects of such pollutants on the thyroid system of Australian native fish be investigated. Copyright © 2016 Elsevier Inc. All rights reserved.

Targeted Next Generation Sequencing with ThyroSeq v2.1 for Indeterminate Thyroid Nodules in Clinical Practice.

PubMed

Witt, Robert L

2016-12-01

To determine if patients elect molecular testing over diagnostic surgery or repeat fine needle aspiration for indeterminate thyroid nodules. Can ThyroSeq v2.1 molecular testing reduce diagnostic thyroid surgery and rule out cancer? Retrospective review Setting: Single institution, single-practice surgeon. Fifteen month retrospective review of indeterminate thyroid nodules that went on to ThyroSeq v2.1 testing. 286 patients met American Thyroid Association guideline criteria for surgeon- performed, ultrasound-guided fine needle aspiration for a thyroid nodule with on-site cytopathology. The indeterminate (Bethesda III or IV) fine needle aspiration cytology rate was 9.1 percent. Prevalence of malignancy in indeterminate nodules was 19 percent. 26/26 (100 percent) patients with indeterminate thyroid nodules elected molecular testing. 16 patients had no mutation, 9 had one or more mutations, and I had no result. 16 of 25 (64 percent) patients with no mutation elected not to undergo diagnostic surgery for indeterminate thyroid nodules. Patients demonstrated a strong preference for molecular testing instead of diagnostic thyroid surgery for indeterminate thyroid nodules. All patients in this series, 25/25 (100 percent) with indeterminate thyroid nodules elected molecular testing instead of repeat biopsy or diagnostic thyroid surgery. 16 of 25 (64 percent) patients tested had no mutation. All 16/16 (100 percent) patients with no mutation on ThyroSeq "rule out" testing elected active surveillance rather than surgery or biopsy, reducing diagnostic surgery. The risk of malignancy among mutation negative patients was not definitively established. There are a number of factors currently that may mute the power of "rule in" testing.

Thyroid disorders in older adults.

PubMed

Visser, W Edward; Visser, Theo J; Peeters, Robin P

2013-06-01

This article summarizes the current literature about serum thyroid parameters and thyroid disease during aging. Changes in thyroid function tests may be part of the physiology of aging, after exclusion of confounding variables. Overt thyroid disease requires immediate treatment. Treatment of subclinical hyperthyroidism in the elderly can be advocated, while watchful waiting may be an appropriate approach for subclinical hypothyroidism. Copyright © 2013 Elsevier Inc. All rights reserved.

Evaluation of the safety and efficacy of radiofrequency ablation for treating benign thyroid nodules

PubMed Central

Tang, Xiaoyin; Cui, Dan; Chi, Jiachang; Wang, Zhi; Wang, Tao; Zhai, Bo; Li, Ping

2017-01-01

Background: Radiofrequency ablation (RFA) is a relatively new procedure for treating benign thyroid nodules. The purpose of this study was to evaluate the safety and efficacy of RFA for treating benign thyroid nodules so as to serve as a reference for future clinical practice. Methods: This study retrospectively analyzed the clinical data of patients receiving percutaneous RFA for treating thyroid nodules from November 2014 to July 2015 in our medical center. One hundred and eight patients with a total of 380 nodules received ultrasound-guided RFA for treating thyroid nodules. Comparisons of the volume change of thyroid nodules before and after RFA treatment, post-treatment complication, and change of thyroid function, were carried out afterwards. Results: Before treatments, all patients received fine needle aspiration biopsy (FNA) which supported the diagnosis of benign tumor. There were 13 males and 95 females included in the study. Twenty-six cases (24.07%) had single nodule, and 82 cases (75.93%) had multiple nodules. Before treatments, the thyroid functions (FT3, FT4, and TSH) were normal originally or adjusted to normal range by endocrinology treatment. The preoperative nodules had minimum volume of 0.01mL, maximum volume of 70.89 mL, and mean volume of 1.02 ± 4.24mL. The volume of nodules one month and three months after RFA were 0.29 ± 0.72mL and 0.15 ± 0.87mL, respectively. In addition, volume reduction ratio (VRR) of nodules one month and three months after RFA were 64.12% and 85.54%, respectively. Both volume of nodules and VRR had statistically significant differences for pre-operative and post-operative comparison (P<0.05). Thyroid functions were in normal range after treatments, and there was no serious complications. Conclusions: Ultrasound-guided RFA treating benign thyroid nodules had the advantages of definite efficacy, safety, strong in control ability, no incision, less damage to surrounding normal tissues and no effect on thyroid function. It can be used as one of the main treatment methods for treating benign thyroid nodules. PMID:28382137

Analysis and functional characterization of sequence variations in ligand binding domain of thyroid hormone receptors in autism spectrum disorder (ASD) patients.

PubMed

Kalikiri, Mahesh Kumar; Mamidala, Madhu Poornima; Rao, Ananth N; Rajesh, Vidya

2017-12-01

Autism spectrum disorder (ASD) is a neuro developmental disorder, reported to be on a rise in the past two decades. Thyroid hormone-T3 plays an important role in early embryonic and central nervous system development. T3 mediates its function by binding to thyroid hormone receptors, TRα and TRβ. Alterations in T3 levels and thyroid receptor mutations have been earlier implicated in neuropsychiatric disorders and have been linked to environmental toxins. Limited reports from earlier studies have shown the effectiveness of T3 treatment with promising results in children with ASD and that the thyroid hormone levels in these children was also normal. This necessitates the need to explore the genetic variations in the components of the thyroid hormone pathway in ASD children. To achieve this objective, we performed genetic analysis of ligand binding domain of THRA and THRB receptor genes in 30 ASD subjects and in age matched controls from India. Our study for the first time reports novel single nucleotide polymorphisms in the THRA and THRB receptor genes of ASD individuals. Autism Res 2017, 10: 1919-1928. ©2017 International Society for Autism Research, Wiley Periodicals, Inc. Thyroid hormone (T3) and thyroid receptors (TRα and TRβ) are the major components of the thyroid hormone pathway. The link between thyroid pathway and neuronal development is proven in clinical medicine. Since the thyroid hormone levels in Autistic children are normal, variations in their receptors needs to be explored. To achieve this objective, changes in THRA and THRB receptor genes was studied in 30 ASD and normal children from India. The impact of some of these mutations on receptor function was also studied. © 2017 International Society for Autism Research, Wiley Periodicals, Inc.

Hyperthyroidism in patients with ischaemic heart disease after iodine load induced by coronary angiography: Long-term follow-up and influence of baseline thyroid functional status.

PubMed

Bonelli, Nadia; Rossetto, Ruth; Castagno, Davide; Anselmino, Matteo; Vignolo, Francesca; Parasiliti Caprino, Mirko; Gaita, Fiorenzo; Ghigo, Ezio; Garberoglio, Roberto; Grimaldi, Roberto; Maccario, Mauro

2018-02-01

To study the effect of a iodine load on thyroid function of patients with ischaemic heart disease (IHD) and the long-term influence of unknown subclinical hyperthyroidism. Subclinical hyperthyroidism is considered an independent risk factors for cardiovascular morbidity of patients with IHD. They routinely undergo coronary angiography with iodine contrast media (ICM) which may induce or even worsen hyperthyroidism. A cross-sectional study followed by a longitudinal study on patients with subclinical hyperthyroidism. 810 consecutive IHD outpatients without known thyroid diseases or treatment with drugs influencing thyroid activity undergoing elective coronary angiography. We evaluated thyroid function either before and 1 month after ICM; patients with thyrotoxicosis at baseline or after ICM were then followed up for 1 year. 58 patients had hyperthyroidism at baseline (HB, 7.2%), independently associated to FT4 levels, thyroid nodules and family history of thyroid diseases. After ICM, the prevalence of hyperthyroidism was 81 (10%). Hyperthyroidism after ICM was positively predicted by baseline fT4 levels, thyroid nodules, age over 60, male gender, family history of thyroid diseases. Three months after ICM, 34 patients (4.2%) still showed hyperthyroidism (22 from HB, 13 treated with methimazole). One year after ICM, hyperthyroidism was still present in 20 patients (2.5%, all from HB, 13 treated). The prevalence of spontaneous subclinical hyperthyroidism in IHD is surprisingly elevated and is further increased by iodine load, particularly in patients with thyroid nodules and familial history of thyroid diseases, persisting in a not negligible number of them even after one year. © 2017 John Wiley & Sons Ltd.

[Effect of combined oral contraceptives on the hypophyseo-thyroid and hypophyseo-adrenal systems in women with various anatomy of the thyroid gland].

PubMed

Zigizmund, V A; Sadykova, M Sh; Samoĭlova, O N; Moiseeva, O M

1988-11-01

Potential therapeutic effects of combined oral contraceptives (COC) rigevidon and ovidon (estrogen:gestagen ratio of 1:5) were studied in 97 women aged 19-35 years. With respect to the anatomical state of the thyroid, the patients were divided into two groups: group 1 included 42 women with normal thyroid function and group 2 included 55 women with euthyroid hyperplasia of the thyroid gland of stage I-II (the anatomical state of the thyroid gland was ranked according to the five-point Swiss scale adopted by WHO in 1975). All patients had a history of pregnancy, normal delivery, or abortion. The state of the pituitary-thyroid system was estimated by absorption of iodine isotopes in the thyroid tissue, and by the blood levels of thyrotropic hormone, thyroxine-binding globulin, thyroxine, and triiodothyronine. Activity of the pituitary- adrenal system was estimated by the blood levels of adrenocorticotropic hormone (ACTH) and cortisol. Blood samples were withdrawn 9 and 10 hours prior to the onset of COC administration, and after 24 and 48 weeks of COC use. The changes in the functional state of the pituitary- thyroid system in groups 1 and 2 were identical throughout the entire period of COC administration. Progressive increase in the levels of thyroxine and triiodothyronine was associated with inhibition of the thyrotropic function of the pituitary seen as decrease in thyrotropin levels. COC administration caused decrease in size of hyperplastic tyroid gland. Prior to COC administration, women in group 2 showed significant elevation of ACTH levels and marked decrease in ACTH levels and increase in cortisol levels in both groups. Normalization of the size of thyroid gland indicated that COC be used therapeutically in patients with thyroid hyperplasia.

Endocrine and cardiac paracrine actions of insulin-like growth factor-I (IGF-I) during thyroid dysfunction in the rat: is IGF-I implicated in the mechanism of heart weight/body weight change during abnormal thyroid function?

PubMed

Thomas, M R; Miell, J P; Taylor, A M; Ross, R J; Arnao, J R; Jewitt, D E; McGregor, A M

1993-06-01

Thyroid hormones are essential for the normal growth and development of many tissues. In the rat, hypothyroidism is associated with growth impairment, and hyperthyroidism with the development of a hypercatabolic state and skeletal muscle wasting but, paradoxically, cardiac hypertrophy. The mechanism by which thyroid hormone produces cardiac hypertrophy and myosin isoenzyme changes remains unclear. The role of IGF-I, an anabolic hormone with both paracrine and endocrine actions, in producing cardiac hypertrophy was investigated during this study in hyperthyroid, hypothyroid and control rats. A treated hypothyroid group was also included in order to assess the effect of acute normalization of thyroid function. Body weight was significantly lower in the hyperthyroid (mean +/- S.E.M.; 535.5 +/- 24.9 g, P < 0.05), hypothyroid (245.3 +/- 9.8 g, P < 0.001) and treated hypothyroid (265.3 +/- 9.8 g, P < 0.001) animals when compared with controls (618.5 +/- 28.6 g). Heart weight/body weight ratios were, however, significantly increased in the hyperthyroid (2.74 +/- 0.11 x 10(-3), P < 0.01) and treated hypothyroid (2.87 +/- 0.07 x 10(-3), P < 0.001) animals when compared with controls (2.26 +/- 0.03 x 10(-3). Serum IGF-I concentrations were similar in the control and hyperthyroid rats (0.91 +/- 0.07 vs 0.78 +/- 0.04 U/ml, P = 0.26), but bioactivity was reduced by 70% in hyperthyroid serum, suggesting a circulating inhibitor of IGF. Serum IGF-I levels (0.12 +/- 0.03 U/ml, P < 0.001) and bioactivity (0.12 +/- 0.04 U/ml, P < 0.001) were significantly lower in the hypothyroid group. Liver IGF-I mRNA levels were not statistically different in the control and hyperthyroid animals, but were significantly reduced in the hypothyroid animals (P < 0.05 vs control). Heart IGF-I mRNA levels were similar in the control and hypothyroid rats, but were significantly increased in the hyperthyroid and treated hypothyroid animals (increased by 32% in hyperthyroidism, P < 0.05; increased by 57% in treated hypothyroidism, P < 0.01). Cardiac IGF-I was significantly elevated in hyperthyroidism (0.16 +/- 0.01 U/mg heart tissue, P < 0.01), was low in hypothyroidism (0.08 +/- 0.01 U/mg, P < 0.01) and was normalized in the treated hypothyroid group (0.11 +/- 0.01 U/mg vs control, 0.13 +/- 0.01 U/mg). Low body mass during both hypothyroidism and hyperthyroidism is therefore associated with reduced systemic IGF bioactivity. In hypothyroidism there is a primary defect in the endocrine function of IGF-I, while in hyperthyroidism serum IGF bioactivity is reduced in the presence of normal endocrine production of this anabolic hormone.(ABSTRACT TRUNCATED AT 400 WORDS)

Generation of Functional Thyroid Tissue Using 3D-Based Culture of Embryonic Stem Cells.

PubMed

Antonica, Francesco; Kasprzyk, Dominika Figini; Schiavo, Andrea Alex; Romitti, Mírian; Costagliola, Sabine

2017-01-01

During the last decade three-dimensional (3D) cultures of pluripotent stem cells have been intensively used to understand morphogenesis and molecular signaling important for the embryonic development of many tissues. In addition, pluripotent stem cells have been shown to be a valid tool for the in vitro modeling of several congenital or chronic human diseases, opening new possibilities to study their physiopathology without using animal models. Even more interestingly, 3D culture has proved to be a powerful and versatile tool to successfully generate functional tissues ex vivo. Using similar approaches, we here describe a protocol for the generation of functional thyroid tissue using mouse embryonic stem cells and give all the details and references for its characterization and analysis both in vitro and in vivo. This model is a valid approach to study the expression and the function of genes involved in the correct morphogenesis of thyroid gland, to elucidate the mechanisms of production and secretion of thyroid hormones and to test anti-thyroid drugs.

Hepatocyte nuclear factor 4alpha contributes to thyroid hormone homeostasis by cooperatively regulating the type 1 iodothyronine deiodinase gene with GATA4 and Kruppel-like transcription factor 9.

PubMed

Ohguchi, Hiroto; Tanaka, Toshiya; Uchida, Aoi; Magoori, Kenta; Kudo, Hiromi; Kim, Insook; Daigo, Kenji; Sakakibara, Iori; Okamura, Masashi; Harigae, Hideo; Sasaki, Takeshi; Osborne, Timothy F; Gonzalez, Frank J; Hamakubo, Takao; Kodama, Tatsuhiko; Sakai, Juro

2008-06-01

Type 1 iodothyronine deiodinase (Dio1), a selenoenzyme catalyzing the bioactivation of thyroid hormone, is highly expressed in the liver. Dio1 mRNA and enzyme activity levels are markedly reduced in the livers of hepatocyte nuclear factor 4alpha (HNF4alpha)-null mice, thus accounting for its liver-specific expression. Consistent with this deficiency, serum T4 and rT3 concentrations are elevated in these mice compared with those in HNF4alpha-floxed control littermates; however, serum T3 levels are unchanged. Promoter analysis of the mouse Dio1 gene demonstrated that HNF4alpha plays a key role in the transactivation of the mouse Dio1 gene. Deletion and substitution mutation analyses demonstrated that a proximal HNF4alpha site (direct repeat 1 [TGGACAAAGGTGC]; HNF4alpha-RE) is crucial for transactivation of the mouse Dio1 gene by HNF4alpha. Mouse Dio1 is also stimulated by thyroid hormone signaling, but a direct role for thyroid hormone receptor action has not been reported. We also showed that thyroid hormone-inducible Krüppel-like factor 9 (KLF9) stimulates the mouse Dio1 promoter very efficiently through two CACCC sequences that are located on either side of HNF4alpha-RE. Furthermore, KLF9 functions together with HNF4alpha and GATA4 to synergistically activate the mouse Dio1 promoter, suggesting that Dio1 is regulated by thyroid hormone in the mouse through an indirect mechanism requiring prior KLF9 induction. In addition, we showed that physical interactions between the C-terminal zinc finger domain (Cf) of GATA4 and activation function 2 of HNF4alpha and between the basic domain adjacent to Cf of GATA4 and a C-terminal domain of KLF9 are both required for this synergistic response. Taken together, these results suggest that HNF4alpha regulates thyroid hormone homeostasis through transcriptional regulation of the mouse Dio1 gene with GATA4 and KLF9.

Hepatocyte Nuclear Factor 4α Contributes to Thyroid Hormone Homeostasis by Cooperatively Regulating the Type 1 Iodothyronine Deiodinase Gene with GATA4 and Krüppel-Like Transcription Factor 9▿ †

PubMed Central

Ohguchi, Hiroto; Tanaka, Toshiya; Uchida, Aoi; Magoori, Kenta; Kudo, Hiromi; Kim, Insook; Daigo, Kenji; Sakakibara, Iori; Okamura, Masashi; Harigae, Hideo; Sasaki, Takeshi; Osborne, Timothy F.; Gonzalez, Frank J.; Hamakubo, Takao; Kodama, Tatsuhiko; Sakai, Juro

2008-01-01

Type 1 iodothyronine deiodinase (Dio1), a selenoenzyme catalyzing the bioactivation of thyroid hormone, is highly expressed in the liver. Dio1 mRNA and enzyme activity levels are markedly reduced in the livers of hepatocyte nuclear factor 4α (HNF4α)-null mice, thus accounting for its liver-specific expression. Consistent with this deficiency, serum T4 and rT3 concentrations are elevated in these mice compared with those in HNF4α-floxed control littermates; however, serum T3 levels are unchanged. Promoter analysis of the mouse Dio1 gene demonstrated that HNF4α plays a key role in the transactivation of the mouse Dio1 gene. Deletion and substitution mutation analyses demonstrated that a proximal HNF4α site (direct repeat 1 [TGGACAAAGGTGC]; HNF4α-RE) is crucial for transactivation of the mouse Dio1 gene by HNF4α. Mouse Dio1 is also stimulated by thyroid hormone signaling, but a direct role for thyroid hormone receptor action has not been reported. We also showed that thyroid hormone-inducible Krüppel-like factor 9 (KLF9) stimulates the mouse Dio1 promoter very efficiently through two CACCC sequences that are located on either side of HNF4α-RE. Furthermore, KLF9 functions together with HNF4α and GATA4 to synergistically activate the mouse Dio1 promoter, suggesting that Dio1 is regulated by thyroid hormone in the mouse through an indirect mechanism requiring prior KLF9 induction. In addition, we showed that physical interactions between the C-terminal zinc finger domain (Cf) of GATA4 and activation function 2 of HNF4α and between the basic domain adjacent to Cf of GATA4 and a C-terminal domain of KLF9 are both required for this synergistic response. Taken together, these results suggest that HNF4α regulates thyroid hormone homeostasis through transcriptional regulation of the mouse Dio1 gene with GATA4 and KLF9. PMID:18426912

Thyroid function appears to be significantly reduced in Space-borne MDS mice

NASA Astrophysics Data System (ADS)

Saverio Ambesi-Impiombato, Francesco; Curcio, Francesco; Fontanini, Elisabetta; Perrella, Giuseppina; Spelat, Renza; Zambito, Anna Maria; Damaskopoulou, Eleni; Peverini, Manola; Albi, Elisabetta

It is known that prolonged space flights induced changes in human cardiovascular, muscu-loskeletal and nervous systems whose function is regulated by the thyroid gland but, until now, no data were reported about thyroid damage during space missions. We have demonstrated in vitro that, during space missions (Italian Soyuz Mission "ENEIDE" in 2005, Shuttle STS-120 "ESPERIA" in 2007), thyroid in vitro cultured cells did not respond to thyroid stimulating hor-mone (TSH) treatment; they appeared healthy and alive, despite their being in a pro-apopotic state characterised by a variation of sphingomyelin metabolism and consequent increase in ce-ramide content. The insensitivity to TSH was largely due to a rearrangement of specific cell membrane microdomains, acting as platforms for TSH-receptor (TEXUS-44 mission in 2008). To study if these effects were present also in vivo, as part of the Mouse Drawer System (MDS) Tissue Sharing Program, we performed experiments in mice maintained onboard the Interna-tional Space Station during the long-duration (90 days) exploration mission STS-129. After return to earth, the thyroids isolated from the 3 animals were in part immediately frozen to study the morphological modification in space and in part immediately used to study the effect of TSH treatment. For this purpose small fragments of tissue were treated with 10-7 or 10-8 M TSH for 1 hour by using untreated fragments as controls. Then the fragments were fixed with absolute ethanol for 10 min at room temperature and centrifuged for 20 min. at 3000 x g. The supernatants were used for cAMP analysis whereas the pellet were used for protein amount determination and for immunoblotting analysis of TSH-receptor, sphingomyelinase and sphingomyelin-synthase. The results showed a modification of the thyroid structure and also the values of cAMP production after treatment with 10-7 M TSH for 1 hour were significantly lower than those obtained in Earth's gravity. The treatment with TSH induced relevant quanti-tative variations of TSH-receptor, sphingomyelinase and sphingomyelin-synthase, probably due to membrane microdomain structure modifications which in turn, as it occurs in vitro, influence the cellular response to TSH treatment.

Fetal Thyroid Function, Birth Weight, and in Utero Exposure to Fine Particle Air Pollution: A Birth Cohort Study.

PubMed

Janssen, Bram G; Saenen, Nelly D; Roels, Harry A; Madhloum, Narjes; Gyselaers, Wilfried; Lefebvre, Wouter; Penders, Joris; Vanpoucke, Charlotte; Vrijens, Karen; Nawrot, Tim S

2017-04-01

Thyroid hormones are critical for fetal development and growth. Whether prenatal exposure to fine particle air pollution (≤ 2.5 μm; PM 2.5 ) affects fetal thyroid function and what the impact is on birth weight in normal healthy pregnancies have not been studied yet. We studied the impact of third-trimester PM 2.5 exposure on fetal and maternal thyroid hormones and their mediating role on birth weight. We measured the levels of free thyroid hormones (FT 3 , FT 4 ) and thyroid-stimulating hormone (TSH) in cord blood ( n = 499) and maternal blood ( n = 431) collected after delivery from mother-child pairs enrolled between February 2010 and June 2014 in the ENVIR ON AGE birth cohort with catchment area in the province of Limburg, Belgium. An interquartile range (IQR) increment (8.2 μg/m 3 ) in third-trimester PM 2.5 exposure was inversely associated with cord blood TSH levels (-11.6%; 95% CI: -21.8, -0.1) and the FT 4 /FT 3 ratio (-62.7%; 95% CI: -91.6, -33.8). A 10th-90th percentile decrease in cord blood FT 4 levels was associated with a 56 g decrease in mean birth weight (95% CI: -90, -23). Assuming causality, we estimated that cord blood FT 4 mediated 21% (-19 g; 95% CI: -37, -1) of the estimated effect of an IQR increment in third-trimester PM 2.5 exposure on birth weight. Third-trimester PM 2.5 exposure was inversely but not significantly associated with maternal blood FT 4 levels collected 1 day after delivery (-4.0%, 95% CI: -8.0, 0.2 for an IQR increment in third-trimester PM 2.5 ). In our study population of normal healthy pregnancies, third-trimester exposure to PM 2.5 air pollution was associated with differences in fetal thyroid hormone levels that may contribute to reduced birth weight. Additional research is needed to confirm our findings in other populations and to evaluate potential consequences later in life.

[Effect of aconite cake-separated moxibustion at Guanyuan (CV 4) and Mingmen (GV 4) on thyroid function in patients of Hashimoto's thyroiditis].

PubMed

Xia, Yong; Xia, Ming-Zhe; Li, Yi; Liu, Shi-Min; Ju, Zi-Yong; He, Jin-Sen

2012-02-01

To explore the effects on thyroid function in patients of Hashimoto's thyroiditis treated with aconite cake-separated moxibustion and option the better therapeutic program. Eighty-five cases were randomly divided into a moxibustion group (42 cases) and a western medication group (43 cases). The moxibustion group was treated by aconite cake-separated moxibustion therapy with acupoints of two groups [(1) Danzhong (CV 17), Zhongwan (CV 12), Guanyuan (CV 4); (2) Dazhui (GV 14), Shenshu (BL 23), Mingmen (GV 4)] alternatively and oral administration of 25 microg Euthyrox everyday. The western medication group was oral administration of 25 microg Euthyrox everyday. Indices of thyroid function before and after treatment and clinical effect were compared between two groups. The clinical total effective rate and effective rate of thyroid function were 25.0% (10/40), 87.5% (35/40) in moxibustion group respectively, 7.53% (3/40) and 57.5% (23/40) in western medication group, with significant differences between two groups (both P < 0.05). Content of serum free thyroxine index (FT4) increased significantly in the moxibustion group after treatment (P < 0.01); content of serum supersensitive thyrotropin (S-TSH) in the moxibustion group was lower than that of western medication group, and contents of serum FT4 and free triiodothyronine (FT3) were higher than those of western medication group, but with no significant differences (all P > 0.05). Aconite cake-separated moxibustion at Guanyuan (CV 4) and Mingmen (GV 4) combined with oral administration of Euthyrox can improve clinical symptoms and thyroid function in patients of Hashimoto's thyroiditis, which is better than simple oral administration of Euthyrox.

Changes in thyroid function in Ethiopian and non-Ethiopian Israeli patients with human immunodeficiency virus infection or acquired immunodeficiency syndrome.

PubMed

Cahn, Avivit; Chairsky-Segal, Irena; Olshtain-Pops, Keren; Maayan, Sholomo; Wolf, Dana; Dresner-Pollak, Rivka

2012-01-01

To investigate whether human immunodeficiency virus (HIV) infection or its treatment is a risk factor for thyroid dysfunction and whether thyroid function changes over time in 2 distinct subpopulations with HIV or acquired immunodeficiency syndrome (AIDS) in Israel: Ethiopian immigrants and Israeli patients. Serum thyroid-stimulating hormone (TSH) and free thyroxine levels were determined in HIV carriers undergoing follow-up at the Hadassah-Hebrew University Medical Center HIV clinic in Jerusalem, Israel, and these thyroid measurements were correlated with clinical and laboratory variables pertaining to their disease, including disease duration, drug therapy, viral load, CD4 count, low-density lipoprotein cholesterol, and creatine kinase. Serum samples stored at -20°C from the time of referral were tested as well. We recruited 121 consecutive patients with HIV or AIDS for this study: 60 Ethiopians and 61 Israeli patients. Of the 121 patients, 4 (3%) had abnormal thyroid function-subclinical hypothyroidism in 2, overt hypothyroidism in 1, and overt hyperthyroidism in 1. Previously stored serum samples were available for 60 of the 121 patients and revealed 2 additional patients with subclinical hypothyroidism, whose TSH has normalized in the subsequent test. Throughout the follow-up period of 3.2 ± 1.9 years, the mean TSH level remained unchanged in the Israeli cohort but significantly declined in the Ethiopian cohort. Thyroid function abnormalities were uncommon in these Israeli patients with HIV or AIDS. This finding does not support the need for routine thyroid function tests in this patient population. The decline in TSH level in the Ethiopian population over time probably represents a shift from an iodine-deficient to an iodine-sufficient country.

Non-Malignant Thyroid Diseases Following a Wide Range of Radiation Exposures

PubMed Central

Ron, Elaine; Brenner, Alina

2013-01-01

Background The thyroid gland is one of the most radiosensitive human organs. While it is well known that radiation exposure increases the risk of thyroid cancer, less is known about its effects in relation to non-malignant thyroid diseases. Objectives The aim of this review is to evaluate the effects of high and low dose radiation on benign structural and functional diseases of the thyroid. Methods We examined the results of major studies from cancer patients treated with high-dose radiotherapy or thyrotoxicosis patients treated with high doses of iodine-131, patients treated with moderate to high dose radiotherapy for benign diseases, persons exposed to low doses from environmental radiation and survivors of the atomic bombings who were exposed to a range of doses. We evaluated radiation effects on structural (tumors, nodules), functional (hyper- and hypothyroidism), and autoimmune thyroid diseases. Results Following a wide range of doses of ionizing radiation, an increased risk of thyroid adenomas and nodules was observed in a variety of populations and settings. The dose response appeared to be linear at low to moderate doses, but in one study there was some suggestion of a reduction in risk above 5 Gy. The elevated risk for benign tumors continues for decades following exposure. Considerably less consistent findings are available regarding functional thyroid diseases including autoimmune diseases. In general, associations for these outcomes were fairly weak and significant radiation effects were most often observed following high doses, particularly for hypothyroidism. Conclusions A significant radiation dose-response relation was demonstrated for benign nodules and follicular adenomas. The effects of radiation on functional thyroid diseases are less clear, partly due to the greater difficulties studying these diseases. PMID:21128812

The Impact of Bariatric Surgery on Thyroid Function and Medication Use in Patients with Hypothyroidism.

PubMed

Zendel, Alex; Abu-Ghanem, Yasmin; Dux, Joseph; Mor, Eyal; Zippel, Douglas; Goitein, David

2017-08-01

Bariatric surgery (BS) is effective in treating obesity and its associated comorbidities. However, there is a paucity of data on the effect of BS on thyroid function in hypothyroid patients, specifically in those treated with thyroid hormone replacement therapy (THR). The aim of this study was to assess the effect of BS on thyroid function and on THR dosage in patients with hypothyroidism. A retrospective analysis of prospectively collected data of all hypothyroid patients who underwent BS between 2010 and 2014 was performed. Data collected included demographic and anthropometric measurements, as well as changes in thyroid hormone levels and THR dosage up to a year from surgery. During the study period, 93 hypothyroid patients (85 females, 91%), 83 of which treated with replacement thyroid hormone, underwent BS. Laparoscopic sleeve gastrectomy was performed in 77 (82.8%) and Roux-en-Y gastric bypass in 16 patients. Average age and body mass index (BMI) were 46.6 ± 11.2 years and 43.7 ± 6.4 kg/m 2 , respectively. Mean BMI and thyroid-stimulating hormone (TSH) significantly deceased after 6 and 12 months following surgery whereas mean free T4 levels remained stable. TSH decrease was directly correlated to baseline TSH but not to BMI reduction. One year after surgery, 11 patients (13.2%) did not require THR, while the rest required a significantly lower average dose (P < 0.02). There is a favorable effect of BS on the hypothyroid bariatric population. This includes improvement of thyroid function and reduction of thyroid medication dosages. Further studies are required to evaluate an influence of THR absorption and compare different types of bariatric surgeries.

The Interaction Between Thyroid and Kidney Disease: An Overview of the Evidence

PubMed Central

Rhee, Connie M.

2016-01-01

Purpose of Review Hypothyroidism is highly prevalent in chronic kidney disease (CKD) patients, including those receiving dialysis. This review examines potential mechanistic links between thyroid and kidney disease; current evidence for hypothyroidism as a risk factor for de novo CKD and CKD progression; and studies of thyroid functional disorders, cardiovascular disease, and death in the CKD population. Recent Findings Epidemiologic data have demonstrated an incrementally higher prevalence of hypothyroidism with increasing severity of kidney dysfunction. Various thyroid functional test abnormalities are also commonly observed in CKD, due to alterations in thyroid hormone synthesis, metabolism, and regulation. While the mechanistic link between thyroid and kidney disease remains unclear, observational studies suggest hypothyroidism is associated with abnormal kidney structure and function. Previously thought to be a physiologic adaptation, recent studies show that hypothyroidism is associated with higher risk of cardiovascular disease and death in CKD. Summary A growing body of evidence suggests that hypothyroidism is a risk factor for incident CKD, CKD progression, and higher death risk in kidney disease patients. Rigorous studies are needed to determine impact of thyroid hormone replacement upon kidney disease progression, cardiovascular disease, and mortality, which may shed light into the causal implications of hypothyroidism in CKD. PMID:27428519

Thyrotoxicosis.

PubMed

Seigel, Stuart C; Hodak, Steven P

2012-03-01

Hyperthyroidism describes the sustained increase in thyroid hormone biosynthesis and secretion by a thyroid gland with increased metabolism. Although the use of radioiodine scanning serves as a useful surrogate that may help characterize the cause of thyrotoxicosis, it only indirectly addresses the underlying physiologic mechanism driving the increase in serum thyroid hormones. In this article, thyrotoxic states are divided into increased or decreased thyroid metabolic function. In addition to the diagnosis, clinical presentation, and treatment of the various causes of hyperthyroidism, a section on functional imaging and appropriate laboratory testing is included. Copyright © 2012 Elsevier Inc. All rights reserved.

Thyroid Autoimmunity is Associated with Decreased Cytotoxicity T Cells in Women with Repeated Implantation Failure

PubMed Central

Huang, Chunyu; Liang, Peiyan; Diao, Lianghui; Liu, Cuicui; Chen, Xian; Li, Guangui; Chen, Cong; Zeng, Yong

2015-01-01

Thyroid autoimmunity (TAI), which is defined as the presence of autoantibodies against thyroid peroxidase (TPO) and/or thyroglobulin (TG), is related to repeated implantation failure (RIF). It is reported that TAI was involved in reproductive failure not only through leading thyroid function abnormality, but it can also be accompanied with immune imbalance. Therefore, this study was designed to investigate the association of thyroid function, immune status and TAI in women with RIF. Blood samples were drawn from 72 women with RIF to evaluate the prevalence of TAI, the thyroid function, the absolute numbers and percentages of lymphocytes. The prevalence of thyroid function abnormality in RIF women with TAI was not significantly different from that in RIF women without TAI (χ2 = 0.484, p > 0.05). The absolute number and percentage of T cells, T helper (Th) cells, B cells and natural killer (NK) cells were not significantly different in RIF women with TAI compared to those without TAI (all p > 0.05). The percentage of T cytotoxicity (Tc) cells was significantly decreased in RIF women with TAI compared to those without TAI (p < 0.05). Meanwhile, Th/Tc ratio was significantly increased (p < 0.05). These results indicated that the decreased Tc percentage and increased Th/Tc ratio may be another influential factor of adverse pregnancy outcomes in RIF women with TAI. PMID:26308040

[Analysis on iodine nutritional status and thyroid function in pregnant women].

PubMed

Li, Hongbo; Wang, Yanling; Zheng, Jing; Wang, Yancai; Huang, Dahong; Liang, Liping; Ren, Xudong; Dou, Yugui; Zhu, Xiaonan

2012-07-01

To investigate the iodine nutritional status and thyroid function of pregnant women during different periods of pregnancy, to provide evidence for guiding iodine supplementation for them. A cross-sectional survey was performed in 90 pregnant women in Wuwei City from April 2009 to January 2010. The morning blood samples and random urine samples were collected, and the thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), free thyroid hormone (FT4), thyroglobulin antibodies (TGAb), thyroid microsomal antibodies (TMAb) in blood samples and iodine in urine samples were detected. The medians of urinary iodine were 231.49, 158.25 and 328.35 microg/L for women in early, middle and late period of pregnancy, The ratio of urinary iodine below 150 microg/L were 39.29%, 45.16% and 25.81%, respectively. The FT3, FT4 levels in the first trimester were higher than those in the third trimester (P < 0.05) and TSH level was increased, but no significant difference (P > 0.05). The positive rate of TGAb and TMAb antibody of pregnant women in different period of time were not significantly different (P > 0.05). The incidence of thyroid function disorder was significantly different in different gestation periods. Generally, the iodine nutritional status of these pregnant women was appropriate, but there was a tendency towards hypothyroid in some women. Monitoring urinary iodine and thyroid function in pregnant women should be carried out regularly.

Clinical associations of maternal thyroid function with foetal brain development: Epidemiological interpretation and overview of available evidence.

PubMed

Korevaar, Tim I M; Tiemeier, Henning; Peeters, Robin P

2018-04-24

Thyroid hormone is an important regulator of early brain development, particularly during early stages of gestation during which foetal thyroid hormone availability depends on the maternal transfer of thyroid hormones. There is a wide range of experimental studies showing that low maternal thyroid hormone availability is associated with suboptimal brain development parameters. While few clinical studies have shown that overt maternal hypothyroidism is associated with lower child IQ, the question whether more subclinical changes in maternal thyroid function could also lead to suboptimal foetal brain development. In this review, we put the latter studies in perspective and discuss their interpretation from an epidemiological and clinical perspective. Furthermore, we extend this discussion to also include future perspective and identify important knowledge gaps in the field. © 2018 John Wiley & Sons Ltd.

Oleuropein and hydroxytyrosol protect rats' pups against bisphenol A induced hypothyroidism.

PubMed

Mahmoudi, Asma; Ghorbel, Hèla; Feki, Ines; Bouallagui, Zouhaier; Guermazi, Fadhel; Ayadi, Lobna; Sayadi, Sami

2018-04-27

Bisphenol A (BPA) can disturb the endocrine system and the organs that respond to endocrine signals in organisms, indirectly exposed during prenatal and/or early postnatal life. The present study was designed to assess the protective effect of phenolic compounds from olive leaves against BPA induced thyroid dysfunction and growth perturbation in young rats during lactation. The BPA disrupting effect on thyroid function was investigated by measuring changes in plasma levels of thyroid hormones. Free triiodothyronine (FT3) and thyroxine (FT4) were decreased in young rats breast-fed from mothers treated with bisphenol A. This effect was associated with an increase in the plasma level of thyroid-stimulating hormone (TSH). The histological and immunohistochemical study of the thyroid gland revealed a disturbance in morphological structure and thyroid cells function. Thyroid dysfunction led to a disruption in the skeletal bone growth of young rats. In fact, the infrared microspectroscopic analysis and histological examination of femoral bone showed significant changes in their histoarchitecture associated with a perturbation in the mechanism of bone tissue mineralization. The administration of oleuropein or hydroxytyrosol in BPA treated lactating mothers improved the thyroid cells function by enhancing thyroid hormone levels. Moreover, these phenolics increased the body growth characterized by an amelioration in the structure and the microstructure of femoral bone tissue. HPLC analysis of rats-breast milk indicated the presence of oleuropein and hydroxytyrosol, which could contribute to the protective effect against bisphenol A induced hypothyroidism in pups rats. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

[Advances in postoperative thyroid-stimulating hormone suppression therapy in females with thyroid cancer].

PubMed

Song, F; Yi, H L

2018-05-07

Differentiated thyroid cancer is the most common malignant carcinoma in female population.Postoperative long-term thyroid-stimulating hormone(TSH) suppression therapy can reduce the risk of recurrence for differentiated thyroid cancer and control the progress of the disease, but it also induces simultaneously subclinical hypothyroidism and imposes negative effect on female. In addition to cardiovascular disease, TSH suppression therapy can lead to the alteration of sex hormone metabolism, menstrual disorder, poor influence on pregnancy and osteoporosis. This article reviews the recent studies on postoperative TSH suppression therapy in women with thyroid cancer.

Thyroid Function in Human Obesity: Underlying Mechanisms.

PubMed

Fontenelle, L C; Feitosa, M M; Severo, J S; Freitas, T E C; Morais, J B S; Torres-Leal, F L; Henriques, G S; do Nascimento Marreiro, D

2016-12-01

Obesity is associated with several metabolic and endocrine disorders; and changes in plasma concentrations, secretion patterns, and clearance of various hormones are observed in obese patients. In this context, recent research has shown that overweight can influence the function of the thyroid gland, usually leading to increased thyrotropin concentrations and changes in the ratio between the hormones triiodothyronine and thyroxine, though within the normal range. The etiology of these changes is still unclear; however, several mechanisms have been proposed including the adaptive process to increase energy expenditure, hyperleptinemia, changes in the activity of deiodinases, the presence of thyroid hormones resistance, chronic low-grade inflammation, and insulin resistance. Although the clinical implications have not been clarified, studies suggest that these changes in the thyroid function of obese individuals may contribute to the worsening of metabolic complications and the development of diseases in the thyroid gland. © Georg Thieme Verlag KG Stuttgart · New York.

Follow-up of differentiated thyroid carcinoma.

PubMed

Pagano, L; Klain, M; Pulcrano, M; Angellotti, G; Pasano, F; Salvatore, M; Lombardi, G; Biondi, B

2004-12-01

Thyroid cancer is the most common endocrine malignancy. More than 90% of primary thyroid cancers are differentiated papillary or follicular types. The treatment of differentiated thyroid carcinoma (DTC) consists of total thyroidectomy and radioactive iodine ablation therapy, followed by L-thyroxine therapy. The extent of initial surgery, the indication for radioiodine ablation therapy and the degree of TSH-suppression are all issues that are still being debated cancers are in relation to the risk of recurrence. Total thyroidectomy reduces the risk of recurrence and facilitates (131)I ablation of thyroid remnants. The aim of radioiodine ablation is to destroy any normal or neoplastic residuals of thyroid tissue. These procedures also improve the sensitivity of thyroglobulin (Tg) as a marker of disease, and increase the sensitivity of (131)I total body scan (TBS) for the detection of persistent or recurrent disease. The aim of TSH-suppressive therapy is to restore euthyroidism and to decrease serum TSH levels, in order to reduce the growth and progression of thyroid cancer. After initial treatment, the objectives of the follow-up of DTC is to maintain adequate thyroxine therapy and to detect persistent or recurrent disease through the combined use of neck ultrasound (US) and serum Tg and (131)I TBS after TSH stimulation. The follow-up protocol should be adapted to the risk of recurrence. Recent advances in the follow-up of DTC are related to the use of recombinant human TSH (rhTSH) in order to stimulate Tg production and the ultrasensitive methods for Tg measurement. Undetectable serum Tg during TSH suppressive therapy with L-T4 does not exclude persistent disease, therefore serum Tg should be measured after TSH stimulation. The results of rhTSH administration and L-thyroxine therapy withdrawal are equivalent in detecting recurrent thyroid cancer, but the use of rhTSH helps to avoid the onset of hypothyroid symptoms and the negative effects of acute hypothyroidism on cardiovascular, hepatic, renal and neurological function. In low-risk DTC patients serum Tg after TSH stimulation, together with ultrasound of the neck, should be used to monitor persistent disease, avoiding diagnostic TBS which has a poor sensitivity. These recommendations do not apply when Tg antibodies are present in the serum, in patients with persistent or recurrent disease or limited thyroid surgery. Low-risk patients may be considered to be in remission when undetectable Tg after TSH stimulation and negative US evaluation of the neck are present. On the contrary, detectable Tg after TSH stimulation is an indicator in selecting patients who are candidates for further diagnostic procedures.

Inhibition of AMPK and Krebs cycle gene expression drives metabolic remodeling of Pten-deficient preneoplastic thyroid cells.

PubMed

Antico Arciuch, Valeria G; Russo, Marika A; Kang, Kristy S; Di Cristofano, Antonio

2013-09-01

Rapidly proliferating and neoplastically transformed cells generate the energy required to support rapid cell division by increasing glycolysis and decreasing flux through the oxidative phosphorylation (OXPHOS) pathway, usually without alterations in mitochondrial function. In contrast, little is known of the metabolic alterations, if any, which occur in cells harboring mutations that prime their neoplastic transformation. To address this question, we used a Pten-deficient mouse model to examine thyroid cells where a mild hyperplasia progresses slowly to follicular thyroid carcinoma. Using this model, we report that constitutive phosphoinositide 3-kinase (PI3K) activation caused by PTEN deficiency in nontransformed thyrocytes results in a global downregulation of Krebs cycle and OXPHOS gene expression, defective mitochondria, reduced respiration, and an enhancement in compensatory glycolysis. We found that this process does not involve any of the pathways classically associated with the Warburg effect. Moreover, this process was independent of proliferation but contributed directly to thyroid hyperplasia. Our findings define a novel metabolic switch to glycolysis driven by PI3K-dependent AMPK inactivation with a consequent repression in the expression of key metabolic transcription regulators. ©2013 AACR.

CHIP promotes thyroid cancer proliferation via activation of the MAPK and AKT pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Li; Liu, Lianyong; Department of Endocrinology, Shanghai Punan Hospital, Shanghai 200125

The carboxyl terminus of Hsp70-interacting protein (CHIP) is a U box-type ubiquitin ligase that plays crucial roles in various biological processes, including tumor progression. To date, the functional mechanism of CHIP in thyroid cancer remains unknown. Here, we obtained evidence of upregulation of CHIP in thyroid cancer tissues and cell lines. CHIP overexpression markedly enhanced thyroid cancer cell viability and colony formation in vitro and accelerated tumor growth in vivo. Conversely, CHIP knockdown impaired cell proliferation and tumor growth. Notably, CHIP promoted cell growth through activation of MAPK and AKT pathways, subsequently decreasing p27 and increasing cyclin D1 and p-FOXO3a expression. Ourmore » findings collectively indicate that CHIP functions as an oncogene in thyroid cancer, and is therefore a potential therapeutic target for this disease. - Highlights: • CHIP is significantly upregulated in thyroid cancer cells. • Overexpression of CHIP facilitates proliferation and tumorigenesis of thyroid cancer cells. • Silencing of CHIP inhibits the proliferation and tumorigenesis of thyroid cancer cells. • CHIP promotes thyroid cancer cell proliferation via activating the MAPK and AKT pathways.« less

Misdiagnosis of Thyroid Disorders in Down Syndrome: Time to Re-Examine the Myth?

ERIC Educational Resources Information Center

Prasher, V.; Haque, M. S.

2005-01-01

There is a reported association between thyroid disorders and Down syndrome, but is this association based on valid and reliable research evidence? We evaluated thyroid function test results of 110 healthy adults with Down syndrome to determine biochemical thyroid status. Approximately two thirds were biochemically euthyroid when assessed by…

Genetically modified mouse models to investigate thyroid development, function and growth.

PubMed

Löf, C; Patyra, K; Kero, A; Kero, J

2018-06-01

The thyroid gland produces thyroid hormones (TH), which are essential regulators for growth, development and metabolism. The thyroid is mainly controlled by the thyroid-stimulating hormone (TSH) that binds to its receptor (TSHR) on thyrocytes and mediates its action via different G protein-mediated signaling pathways. TSH primarily activates the G s -pathway, and at higher concentrations also the G q/11 -pathway, leading to an increase of intracellular cAMP and Ca 2+ , respectively. To date, the physiological importance of other G protein-mediated signaling pathways in thyrocytes is unclear. Congenital hypothyroidism (CH) is defined as the lack of TH at birth. In familial cases, high-throughput sequencing methods have facilitated the identification of novel mutations. Nevertheless, the precise etiology of CH yet remains unraveled in a proportion of cases. Genetically modified mouse models can reveal new pathophysiological mechanisms of thyroid diseases. Here, we will present an overview of genetic mouse models for thyroid diseases, which have provided crucial insights into thyroid gland development, function, and growth with a special focus on TSHR and microRNA signaling. Copyright © 2018 Elsevier Ltd. All rights reserved.

Role of endoplasmic reticulum stress-induced apoptosis in rat thyroid toxicity caused by excess fluoride and/or iodide.

PubMed

Liu, Hongliang; Hou, Changchun; Zeng, Qiang; Zhao, Liang; Cui, Yushan; Yu, Linyu; Wang, Lingzhi; Zhao, Yang; Nie, Junyan; Zhang, Bin; Wang, Aiguo

2016-09-01

Excess fluoride and iodide coexist in drinking water in many regions, but few studies have investigated the single or interactive effects on thyroid in vivo. In our study, Wistar rats were exposed to excess fluoride and/or iodide through drinking water for 2 or 8 months. The structure and function of the thyroid, cells apoptosis and the expression of inositol-requiring enzyme 1 (IRE1) pathway-related factors were analyzed. Results demonstrated that excess fluoride and/or iodide could change thyroid follicular morphology and alter thyroid hormone levels in rats. After 8 months treatment, both single and co-exposure of the two microelements could raise the thyroid cells apoptosis. However, the expressions of IRE1-related factors were only increased in fluoride-alone and the combined groups. In conclusion, thyroid structure and thyroid function were both affected by excess fluoride and/or iodide. IRE1-induced apoptosis were involved in this cytotoxic process caused by fluoride or the combination of two microelements. Copyright © 2016 Elsevier B.V. All rights reserved.

Pregnancy outcomes are not altered by variation in thyroid function within the normal range in women free of thyroid disease.

PubMed

Veltri, Flora; Kleynen, Pierre; Grabczan, Lidia; Salajan, Alexandra; Rozenberg, Serge; Pepersack, Thierry; Poppe, Kris

2018-02-01

In the recently revised guidelines on the management of thyroid dysfunction during pregnancy, treatment with thyroid hormone (LT4) is not recommended in women without thyroid autoimmunity (TAI) and TSH levels in the range 2.5-4.0 mIU/L, and in a recent study in that particular group of pregnant women, more complications were observed when a treatment with LT4 was given. The objective of the study was therefore to investigate whether variation in thyroid function within the normal (non-pregnant) range in women free of thyroid disease was associated with altered pregnancy outcomes? Cross-sectional data analysis of 1321 pregnant women nested within an ongoing prospective collection of pregnant women's data in a single centre in Brussels, Belgium. Thyroid peroxidase antibodies (TPO-abs), thyroid-stimulating hormone (TSH), free T4 (FT4) and ferritin levels were measured and baseline characteristics were recorded. Women taking LT4, with TAI and thyroid function outside the normal non-pregnant range were excluded. Pregnancy outcomes and baseline characteristics were correlated with all TSH and FT4 levels within the normal range and compared between two groups (TSH cut-off < and ≥2.5 mIU/L). Tobacco use was associated with higher serum TSH levels (OR: 1.38; CI 95%: 1.08-1.74); P  = 0.009. FT4 levels were inversely correlated with age and BMI (rho = -0.096 and -0.089; P  < 0.001 and 0.001 respectively) and positively correlated with ferritin levels (rho = 0.097; P  < 0.001). Postpartum haemorrhage (>500 mL) was inversely associated with serum FT4 levels (OR: 0.35; CI 95%: 0.13-0.96); P  = 0.040. Also 10% of women free of thyroid disease had serum TSH levels ≥2.5 mIU/L. Variation in thyroid function during the first trimester within the normal (non-pregnant) range in women free of thyroid disease was not associated with altered pregnancy outcomes. These results add evidence to the recommendation against LT4 treatment in pregnant women with high normal TSH levels and without TPO antibodies. © 2018 European Society of Endocrinology.

Zebrafish bcl2l is a survival factor in thyroid development.

PubMed

Porreca, Immacolata; De Felice, Elena; Fagman, Henrik; Di Lauro, Roberto; Sordino, Paolo

2012-06-15

Regulated cell death, defined in morphological terms as apoptosis, is crucial for organ morphogenesis. While differentiation of the thyroid gland has been extensively studied, nothing is yet known about the survival mechanisms involved in the development of this endocrine gland. Using the zebrafish model system, we aim to understand whether genes belonging to the Bcl-2 family that control apoptosis are implicated in regulation of cell survival during thyroid development. Evidence of strong Bcl-2 gene expression in mouse thyroid precursors prompted us to investigate the functions played by its zebrafish homologs during thyroid development. We show that the bcl2-like (bcl2l) gene is expressed in the zebrafish thyroid primordium. Morpholino-mediated knockdown and mutant analyses revealed that bcl2l is crucial for thyroid cell survival and that this function is tightly modulated by the transcription factors pax2a, nk2.1a and hhex. Also, the bcl2l gene appears to control a caspase-3-dependent apoptotic mechanism during thyroid development. Thyroid precursor cells require an actively maintained survival mechanism to properly proceed through development. The bcl2l gene operates in the inhibition of cell death under direct regulation of a thyroid specific set of transcription factors. This is the first demonstration of an active mechanism to ensure survival of the thyroid primordium during morphogenesis. Copyright © 2012 Elsevier Inc. All rights reserved.

Correlation between serum lead and thyroid diseases: papillary thyroid carcinoma, nodular goiter, and thyroid adenoma.

PubMed

Li, Hui; Li, Xiang; Liu, Jie; Jin, Langping; Yang, Fan; Wang, Junbo; Wang, Ouchen; Gao, Ying

2017-10-01

Studies have showed that lead was associated with human health. However, the effects of lead on thyroid functions are inconsistent, and studies based on Chinese population are fragmentary. To evaluate the correlation between lead and thyroid functions of Chinese with different thyroid diseases, we conducted a hospital-based study. Ninety-six papillary thyroid carcinoma (PTC), 10 nodular goiter (NG), and 7 thyroid adenoma (TA) patients were recruited from the First Affiliated Hospital of Wenzhou Medical University, China. Serum triiodothyronine (T3), free triiodothyronine (FT3), free thyroxin (FT4), and thyroid stimulating hormone (TSH) were evaluated with chemiluminescent microparticle immunoassay. Serum lead was assessed with ICP-MASS. Partial correlation was used to explore the correlations of serum lead and thyroid diseases. Compared to PTC, the level of lead was significantly higher in TA, and lower in NG (p < 0.05). This difference remained significant in females when stratified by sex. Serum lead was negatively correlated with TSH (r s  =  - 0.27, p < 0.05) in PTC group. T3 was positively related to lead at quartile4 (r s  = 0.61, p < 0.05) in PTC group. No significant correlations were observed between lead and FT3 or FT4 in any group. The results suggested that lead might have different etiological roles in these three thyroid diseases.

The effect of consuming Palmaria palmata-enriched bread on inflammatory markers, antioxidant status, lipid profile and thyroid function in a randomised placebo-controlled intervention trial in healthy adults.

PubMed

Allsopp, Philip; Crowe, William; Bahar, Bojlul; Harnedy, Pádraigín A; Brown, Emma S; Taylor, Sonja S; Smyth, Thomas J; Soler-Vila, Anna; Magee, Pamela J; Gill, Chris I R; Strain, Conall R; Hegan, Vicky; Devaney, Martin; Wallace, Julie M W; Cherry, Paul; FitzGerald, Richard J; Strain, J J; O'Doherty, John V; McSorley, Emeir M

2016-08-01

Palmaria palmata (P. Palmata) is reported to contain anti-inflammatory and antioxidant compounds albeit no study has investigated these effects in humans. A randomised parallel placebo-controlled human intervention study was carried out to investigate the effect of consuming P. Palmata (5 g/day) incorporated into a bread on serum markers of inflammation [C-reactive protein (CRP); cytokine analysis] with secondary analysis investigating changes in lipids (cholesterol, triglycerides), thyroid function [thyroid-stimulating hormone (TSH)] and antioxidant status ferric reducing antioxidant power. ANCOVA with baseline values as covariates, controlling for age, BMI, sex and smoking status, was used to compare differences between treatment groups over time . In vitro studies investigated the inflammatory activity of P. Palmata extracts (hot water, cold water and ethanol extract), protein extracts and associated protein hydrolysates using a Caco-2 inflammation cell model. Consumption of P. Palmata-enriched bread significantly increased serum CRP (+16.1 %, P = 0.011), triglycerides (+31.9 %, P = 0.001) and TSH (+17.2 %, P = 0.017) when compared to the control group. In vitro evaluation of P. palmata extracts and protein hydrolysates identified a significant induction of IL-8 secretion by Caco-2 cells, and the hot water P. palmata extract was shown to increase adipocyte glycerol release (P < 0.05). Evidence from this human study suggests that P. palmata stimulates inflammation, increases serum triglycerides and alters thyroid function; however, these changes are not likely to impact health as changes remained within the normal clinical range. The data from the in vitro study provided indications that IL-8 may contribute to the apparent immunostimulation noted in the human study.

TAS2R bitter taste receptors regulate thyroid function

PubMed Central

Clark, Adam A.; Dotson, Cedrick D.; Elson, Amanda E. T.; Voigt, Anja; Boehm, Ulrich; Meyerhof, Wolfgang; Steinle, Nanette I.; Munger, Steven D.

2015-01-01

Dysregulation of thyroid hormones triiodothyronine and thyroxine (T3/T4) can impact metabolism, body composition, and development. Thus, it is critical to identify novel mechanisms that impact T3/T4 production. We found that type 2 taste receptors (TAS2Rs), which are activated by bitter-tasting compounds such as those found in many foods and pharmaceuticals, negatively regulate thyroid-stimulating hormone (TSH)-dependent Ca2+ increases and TSH-dependent iodide efflux in thyrocytes. Immunohistochemical Tas2r-dependent reporter expression and real-time PCR analyses reveal that human and mouse thyrocytes and the Nthy-Ori 3-1 human thyrocyte line express several TAS2Rs. Five different agonists for thyrocyte-expressed TAS2Rs reduced TSH-dependent Ca2+ release in Nthy-Ori 3-1 cells, but not basal Ca2+ levels, in a dose-dependent manner. Ca2+ responses were unaffected by 6-n-propylthiouracil, consistent with the expression of an unresponsive variant of its cognate receptor, TAS2R38, in these cells. TAS2R agonists also inhibited basal and TSH-dependent iodide efflux. Furthermore, a common TAS2R42 polymorphism is associated with increased serum T4 levels in a human cohort. Our findings indicate that TAS2Rs couple the detection of bitter-tasting compounds to changes in thyrocyte function and T3/T4 production. Thus, TAS2Rs may mediate a protective response to overingestion of toxic materials and could serve as new druggable targets for therapeutic treatment of hypo- or hyperthyroidism.—Clark, A. A., Dotson, C. D., Elson, A. E. T., Voigt, A., Boehm, U., Meyerhof, W., Steinle, N. I., Munger, S. D. TAS2R bitter taste receptors regulate thyroid function. PMID:25342133

[The effect of hypothyroidism on cardiac function in dogs].

PubMed

Stephan, I; Nolte, I; Hoppen, H O

2003-06-01

The thyroid hormones have direct and indirect effects on the heart. So it is possible that depression of left ventricular function is associated with hypothyroidism. This publication describes cardiac findings (auscultation, electrocardiography, echocardiography) in ten hypothyroid dogs. Low heart rates, reduced R-amplitudes and bradycardic arrhythmias (first and second-degree AV block) were found on the electrocardiogram before treatment. On the echocardiograms most of the dogs showed reduced contractillity and reduced left ventricular wall thickness. Seven dogs were reexamined after levothyroxine supplementation. Effects of treatment were increased heart rates and R-amplitudes as well as disappearance of the bradycardic arrhythmias in electrocardiographic examination. The echocardiographic examination showed increased contractility and increased left ventricular wall thickness.

Thyroid function and neuropsychological status in older adults.

PubMed

Shrestha, Srishti; Bloom, Michael S; Yucel, Recai; Seegal, Richard F; Rej, Robert; McCaffrey, Robert J; Fitzgerald, Edward F

2016-10-01

Overt thyroid dysfunction is recognized as a risk factor for neuropsychological deficits in aging populations, yet evidence for how changes in levels of circulatory thyroid hormones impact specific neuropsychological domains is limited. Here we report cross-sectional associations between serum thyroid hormone concentrations and several neuropsychological function domains among men and women aged 55-74years. We administered neuropsychological tests to assess memory, learning, executive function, measures of attention, visuospatial function, affective state, and motor function. Multivariable linear regression analyses were performed adjusting for age, sex, education, and cigarette smoking. Effects were reported as differences in test scores per one interquartile range (IQR) increase in hormone concentration. Higher total thyroxine (T4) and free thyroxine (fT4) were associated with improved visuospatial function, as measured by Block Design Subtest total scores; associated increments per IQR differences in T4 and fT4 were 15% and 19%, respectively (false discovery rate q-values <0.05). We also detected statistical interactions between age and fT4 for effects in tasks of memory and learning. Concurrent increases in age and fT4 were associated with deficits in memory and learning as measured by California Verbal Learning Test subtests (10% and 16% deficits in t-score and short delay free recall score, respectively). Our findings suggest that changes in thyroid hormones may have important implications for neuropsychological function in aging populations. Further large-scale studies with comprehensive thyroid function and neuropsychological outcome assessments are warranted to confirm these results. Copyright © 2016 Elsevier Inc. All rights reserved.

Cytophysiological Changes in the Follicular Epithelium of the Thyroid Gland after Long-Term Exposure to Low Doses of Dichlorodiphenyltrichloroethane (DDT).

PubMed

Yaglova, N V; Yaglov, V V

2017-03-01

Exposure to endocrine disruptors is considered as a risk factor thyroid gland diseases. We analyzed cytophysiological changes in rat thyroid follicular epithelium after long-term exposure to low doses of the most widespread disruptor DDT. Analysis of thyroid hormone production and light and electron microscopy of thyroid gland samples revealed cytophysiological changes in thyroid epithelium related to impaired transport through the apical membrane, suppressed Golgi complex activity, and impaired thyrotrophic hormone regulation of the secretory functions of thyroid cells, which led to compensatory transition from merocrine to microapocrine secret release.

Functional expression of the thyrotropin receptor in C cells: new insights into their involvement in the hypothalamic-pituitary-thyroid axis

PubMed Central

Morillo-Bernal, Jesús; Fernández-Santos, José M; Utrilla, José C; de Miguel, Manuel; García-Marín, Rocío; Martín-Lacave, Inés

2009-01-01

Thyroid C cells, or parafollicular cells, are mainly known for producing calcitonin, a hormone involved in calcium homeostasis with hypocalcemic and hypophosphatemic effects. Classically, the main endocrine activity of this cell population has been believed to be restricted to its roles in serum calcium and bone metabolism. Nonetheless, in the last few years evidence has been accumulating in the literature with regard to local regulatory peptides secreted by C cells, such as somatostatin, ghrelin, thyrotropin releasing hormone or the recently described cocaine- and amphetamine-related transcript, which could modify thyroid function. As thyrotropin is the main hormone controlling the hypothalamic-pituitary-thyroid axis and, accordingly, thyroid function, we have examined the functional expression of the thyrotropin receptor in C-cell lines and in thyroid tissues. We have found that rat and human C-cell lines express the thyrotropin receptor at both mRNA and protein levels. Furthermore, incubation of C cells with thyrotropin resulted in a 10-fold inhibition of thyrotropin-receptor expression, and a concomitant decrease of the steady-state mRNA levels for calcitonin and calcitonin gene-related peptide determined by quantitative real-time PCR was found. Finally, thyrotropin receptor expression by C cells was confirmed at protein level in both normal and pathological thyroid tissues by immunohistochemistry and immunofluorescence. These results confirm that C cells, under regulation by thyrotropin, are involved in the hypothalamic-pituitary-thyroid axis and suggest a putative role in local fine-tuning of follicular cell activity. PMID:19493188

Fluoride exposure and indicators of thyroid functioning in the Canadian population: implications for community water fluoridation

PubMed Central

Barberio, Amanda M; Hosein, F Shaun; Quiñonez, Carlos; McLaren, Lindsay

2017-01-01

Background There are concerns that altered thyroid functioning could be the result of ingesting too much fluoride. Community water fluoridation (CWF) is an important source of fluoride exposure. Our objectives were to examine the association between fluoride exposure and (1) diagnosis of a thyroid condition and (2) indicators of thyroid functioning among a national population-based sample of Canadians. Methods We analysed data from Cycles 2 and 3 of the Canadian Health Measures Survey (CHMS). Logistic regression was used to assess associations between fluoride from urine and tap water samples and the diagnosis of a thyroid condition. Multinomial logistic regression was used to examine the relationship between fluoride exposure and thyroid-stimulating hormone (TSH) level (low/normal/high). Other available variables permitted additional exploratory analyses among the subset of participants for whom we could discern some fluoride exposure from drinking water and/or dental products. Results There was no evidence of a relationship between fluoride exposure (from urine and tap water) and the diagnosis of a thyroid condition. There was no statistically significant association between fluoride exposure and abnormal (low or high) TSH levels relative to normal TSH levels. Rerunning the models with the sample constrained to the subset of participants for whom we could discern some source(s) of fluoride exposure from drinking water and/or dental products revealed no significant associations. Conclusion These analyses suggest that, at the population level, fluoride exposure is not associated with impaired thyroid functioning in a time and place where multiple sources of fluoride exposure, including CWF, exist. PMID:28839078

Development of the thyroid gland.

PubMed

Nilsson, Mikael; Fagman, Henrik

2017-06-15

Thyroid hormones are crucial for organismal development and homeostasis. In humans, untreated congenital hypothyroidism due to thyroid agenesis inevitably leads to cretinism, which comprises irreversible brain dysfunction and dwarfism. Elucidating how the thyroid gland - the only source of thyroid hormones in the body - develops is thus key for understanding and treating thyroid dysgenesis, and for generating thyroid cells in vitro that might be used for cell-based therapies. Here, we review the principal mechanisms involved in thyroid organogenesis and functional differentiation, highlighting how the thyroid forerunner evolved from the endostyle in protochordates to the endocrine gland found in vertebrates. New findings on the specification and fate decisions of thyroid progenitors, and the morphogenesis of precursor cells into hormone-producing follicular units, are also discussed. © 2017. Published by The Company of Biologists Ltd.

New insights for male infertility revealed by alterations in spermatic function and differential testicular expression of thyroid-related genes.

PubMed

Romano, Renata Marino; Gomes, Samantha Nascimento; Cardoso, Nathalia Carolina Scandolara; Schiessl, Larissa; Romano, Marco Aurelio; Oliveira, Claudio Alvarenga

2017-02-01

The impact of thyroid hormone (TH) disorders on male reproductive biology has been a controversial issue for many years. Recently, we reported that hypothyroid male rats have a disruption of the seminiferous epithelium, which may compromise spermatogenesis. To improve the understanding of the reproductive pathogenesis of hypothyroidism and hyperthyroidism, male Wistar rats that developed these dysfunctions in adulthood were used as an experimental model. We evaluated the sperm production, reserves, transit time, morphology, and functionality (acrosome integrity, plasma membrane integrity, and mitochondrial activity), and the testicular expression of the TH receptors (Thra1 and Thra2, Thrb1, and Thrb2), deiodinases (Dio2 and Dio3), and the Mct8 transporter (Slc16a2) were assessed by reverse transcription followed by real-time quantitative PCR (RT-qPCR). The results were evaluated statistically by ANOVA and Tukey HSD test (P < 0.05). Hypothyroidism decreased the total and daily sperm productions and increased the sperm transit time through the epididymis, while the sperm functionality was reduced in both thyroid dysfunctions. Regarding the modulation of gene expression in the testis, hypothyroidism increased the expression of Thra1 and decreased the expression of Dio3, and hyperthyroidism increased the expression of Slc16a2. The observed alterations in spermatic production and function and in the expression of the TH receptor, deiodinase, and the TH transporter are suggestive of TH participation in spermatogenesis in adulthood.

Effects of acute postnatal exposure to 3,3',4,4'-tetrachlorobiphenyl on sperm function and hormone levels in adult rats.

PubMed

Hsu, Ping-Chi; Guo, Yueliang Leon; Li, Mei-Hui

2004-02-01

Polychlorinated biphenyls (PCBs) are considered potential endocrine disruptors due to their ability to act as estrogens, antiestrogens and goitrogens. The aim of this study is to ascertain whether acute postnatal treatment with 3,3',4,4'-tetrachlorobiphenyl (CB 77) affects sperm function and hormone levels in adult rats. Male Sprague-Dawley rats received CB 77 by ip injection of 2 or 20 mg/kg at day 21 and sacrificed at day 112. At day 112, right and left testis weights were significantly increased, whereas sperm count, motility, total motile sperm count, curvilinear velocity, average path velocity, straight-line velocity, and beat-cross frequency for motile sperm were significantly decreased in rats treated with 20 mg/kg CB 77. Sperm-oocyte penetration rate was significantly reduced in rats treated with either 2 or 20 mg/kg CB 77. There was high sperm acrosome reaction rate (ARR) in the 20 mg/kg CB 77-treated rats. There was a significant increase in thyroid-stimulating hormone level in the 20 mg/kg CB 77 group. However, no changes were seen in serum testosterone, thyroid hormones, or prolactin concentrations at day 112. In summary, this study showed that postnatal exposure to CB 77 might affect spermatogenesis, motility, ARR, and ability of fertilizing oocytes in mature rats. These results suggest that the sperm functions may be more susceptible or adapt less readily than the thyroid functions to endocrine disruption caused by dioxin-like PCB congeners.

Iodine status and thyroid function of Boston-area vegetarians and vegans.

PubMed

Leung, Angela M; Lamar, Andrew; He, Xuemei; Braverman, Lewis E; Pearce, Elizabeth N

2011-08-01

Adequate dietary iodine is required for normal thyroid function. The iodine status and thyroid function of U.S. vegetarians and vegans have not been previously studied. Environmental perchlorate and thiocyanate (inhibitors of thyroid iodine uptake) exposures may adversely affect thyroid function. The objective of the study was to assess the iodine status and thyroid function of U.S. vegetarians (consume plant based products, eggs, milk; abstain from meat, poultry, fish, shellfish) and vegans (avoid all animal products) and whether these may be affected by environmental perchlorate and thiocyanate exposures. This was a cross-sectional assessment of urinary iodine, perchlorate, and thiocyanate concentrations and serum thyroid function in Boston-area vegetarians and vegans. One hundred forty-one subjects (78 vegetarians, 63 vegans) were recruited; one vegan was excluded. Median urinary iodine concentration of vegans (78.5 μg/liter; range 6.8-964.7 μg/liter) was lower than vegetarians (147.0 μg/liter; range 9.3-778.6 μg/liter) (P < 0.01). Adjusted for cigarette smoking (confirmed by urinary cotinine levels) and thiocyanate-rich food consumption, median urinary thiocyanate concentration of vegans (630 μg/liter; range 108-3085 μg/liter) was higher than vegetarians (341 μg/liter; range 31-1963 μg/liter) (P < 0.01). There were no between-group differences in urinary perchlorate concentrations (P = 0.75), TSH (P = 0.46), and free T(4) (P = 0.77). Urinary iodine, perchlorate, and thiocyanate levels were not associated with TSH (P = 0.59) or free T(4) (P = 0.14), even when adjusted for multiple variables. U.S. vegetarians are iodine sufficient. U.S. vegans may be at risk for low iodine intake, and vegan women of child-bearing age should supplement with 150 μg iodine daily. Environmental perchlorate and thiocyanate exposures are not associated with thyroid dysfunction in these groups.

Iodine Status and Thyroid Function of Boston-Area Vegetarians and Vegans

PubMed Central

LaMar, Andrew; He, Xuemei; Braverman, Lewis E.; Pearce, Elizabeth N.

2011-01-01

Context: Adequate dietary iodine is required for normal thyroid function. The iodine status and thyroid function of U.S. vegetarians and vegans have not been previously studied. Environmental perchlorate and thiocyanate (inhibitors of thyroid iodine uptake) exposures may adversely affect thyroid function. Objective: The objective of the study was to assess the iodine status and thyroid function of U.S. vegetarians (consume plant based products, eggs, milk; abstain from meat, poultry, fish, shellfish) and vegans (avoid all animal products) and whether these may be affected by environmental perchlorate and thiocyanate exposures. Design and Setting: This was a cross-sectional assessment of urinary iodine, perchlorate, and thiocyanate concentrations and serum thyroid function in Boston-area vegetarians and vegans. Subjects: One hundred forty-one subjects (78 vegetarians, 63 vegans) were recruited; one vegan was excluded. Results: Median urinary iodine concentration of vegans (78.5 μg/liter; range 6.8–964.7 μg/liter) was lower than vegetarians (147.0 μg/liter; range 9.3–778.6 μg/liter) (P < 0.01). Adjusted for cigarette smoking (confirmed by urinary cotinine levels) and thiocyanate-rich food consumption, median urinary thiocyanate concentration of vegans (630 μg/liter; range 108-3085 μg/liter) was higher than vegetarians (341 μg/liter; range 31–1963 μg/liter) (P < 0.01). There were no between-group differences in urinary perchlorate concentrations (P = 0.75), TSH (P = 0.46), and free T4 (P = 0.77). Urinary iodine, perchlorate, and thiocyanate levels were not associated with TSH (P = 0.59) or free T4 (P = 0.14), even when adjusted for multiple variables. Conclusions: U.S. vegetarians are iodine sufficient. U.S. vegans may be at risk for low iodine intake, and vegan women of child-bearing age should supplement with 150 μg iodine daily. Environmental perchlorate and thiocyanate exposures are not associated with thyroid dysfunction in these groups. PMID:21613354

Italian Association of Clinical Endocrinologists (AME) & Italian Association of Clinical Diabetologists (AMD) Position Statement : Diabetes mellitus and thyroid disorders: recommendations for clinical practice.

PubMed

Guastamacchia, Edoardo; Triggiani, Vincenzo; Aglialoro, Alberto; Aiello, Antimo; Ianni, Lucia; Maccario, Mauro; Zini, Michele; Giorda, Carlo; Guglielmi, Rinaldo; Betterle, Corrado; Attanasio, Roberto; Borretta, Giorgio; Garofalo, Piernicola; Papini, Enrico; Castello, Roberto; Ceriello, Antonio

2015-06-01

Thyroid disease and diabetes mellitus, the most common disorders in endocrine practice, are not infrequently associated in the same subject. An altered thyroid function may affect glucose tolerance and worsen metabolic control in patients with diabetes. Thyrotoxicosis increases the risk of hyperglycemic emergencies, while a clinically relevant hypothyroidism may have a detrimental effect on glycemic control in diabetic patients. The association of alterations in thyroid function with diabetes mellitus may adversely affect the risk of cardiovascular and microvascular complications resulting from diabetes. Moreover, the treatments used for both diabetes and thyroid disease, respectively, can impact one other. Finally, multinodular goiter, but not thyroid carcinoma, was shown to be more prevalent in type 2 diabetes mellitus. Aim of the present Position Statement is to focus on the evidence concerning the association of thyroid disease and diabetes mellitus and to provide some practical suggestions for an updated clinical management.

The environmental contaminant tributyltin leads to abnormalities in different levels of the hypothalamus-pituitary-thyroid axis in female rats.

PubMed

Andrade, Marcelle Novaes; Santos-Silva, Ana Paula; Rodrigues-Pereira, Paula; Paiva-Melo, Francisca Diana; de Lima Junior, Niedson Correa; Teixeira, Mariana Pires; Soares, Paula; Dias, Glaecir Roseni Munstock; Graceli, Jones Bernardes; de Carvalho, Denise Pires; Ferreira, Andrea Claudia Freitas; Miranda-Alves, Leandro

2018-06-11

Tributyltin is a biocide used in nautical paints, aiming to reduce fouling of barnacles in ships. Despite the fact that many effects of TBT on marine species are known, studies in mammals have been limited, especially those evaluating its effect on the function of the hypothalamus-pituitary-thyroid (HPT) axis. The aim of this study was to investigate the effects of subchronic exposure to TBT on the HPT axis in female rats. Female Wistar rats received vehicle, TBT 200 ng kg -1 BW d -1 or 1000 ng kg -1 BW d -1 orally by gavage for 40 d. Hypothalamus, pituitary, thyroid, liver and blood samples were collected. TBT200 and TBT1000 thyroids showed vacuolated follicular cells, with follicular hypertrophy and hyperplasia. An increase in epithelial height and a decrease in the thyroid follicle and colloid area were observed in TBT1000 rats. Moreover, an increase in the epithelium/colloid area ratio was observed in both TBT groups. Lower TRH mRNA expression was observed in the hypothalami of TBT200 and TBT1000 rats. An increase in Dio1 mRNA levels was observed in the hypothalamus and thyroid in TBT1000 rats only. TSH serum levels were increased in TBT200 rats. In TBT1000 rats, there was a decrease in total T4 serum levels compared to control rats, whereas T3 serum levels did not show significant alterations. We conclude that TBT exposure can promote critical abnormalities in the HPT axis, including changes in TRH mRNA expression and serum TSH and T4 levels, in addition to affecting thyroid morphology. These findings demonstrate that TBT disrupts the HPT axis. Additionally, the changes found in thyroid hormones suggest that TBT may interfere with the peripheral metabolism of these hormones, an idea corroborated by the observed changes in Dio1 mRNA levels. Therefore, TBT exposition might interfere not only with the thyroid axis but also with thyroid hormone metabolism. Copyright © 2018 Elsevier Ltd. All rights reserved.

The Effect of Ezetimibe/Statin Combination and High-Dose Statin Therapy on Thyroid Autoimmunity in Women with Hashimoto's Thyroiditis and Cardiovascular Disease: A Pilot Study.

PubMed

Krysiak, R; Szkróbka, W; Okopień, B

2016-10-01

Background: Intensive statin therapy was found to reduce thyroid autoimmunity in women with Hashimoto's thyroiditis. No similar data are available for other hypolipidemic agents. Methods: The participants of the study were 16 women with Hashimoto's thyroiditis and coronary artery disease. On the basis of statin tolerance, they were divided into 2 groups. 8 patients who did not tolerate high-dose statin therapy were treated with a statin, the dose of which was reduced by half, together with ezetimibe. The remaining 8 patients tolerating the treatment continued high-dose statin therapy. Plasma lipids, serum levels of thyrotropin, free thyroxine and free triiodothyronine, as well as titers of thyroid peroxidase and thyroglobulin antibodies were measured at the beginning of the study and 6 months later. Results: Replacing high-dose statin therapy with ezetimibe/statin combination therapy increased serum titers of thyroid peroxidase as well as led to an insignificant increase in serum titers of thyroglobulin antibodies. At the end of the study, thyroid peroxidase and thyroglobulin antibody titers were higher in patients receiving the combination therapy than in those treated only with high-dose statin. Conclusions: Our study shows that high-dose statin therapy produces a stronger effect on thyroid autoimmunity than ezetimibe/statin combination therapy. © Georg Thieme Verlag KG Stuttgart · New York.

US-guided percutaneous radiofrequency thermal ablation for the treatment of solid benign hyperfunctioning or compressive thyroid nodules.

PubMed

Deandrea, Maurilio; Limone, Paolo; Basso, Edoardo; Mormile, Alberto; Ragazzoni, Federico; Gamarra, Elena; Spiezia, Stefano; Faggiano, Antongiulio; Colao, Annamaria; Molinari, Filippo; Garberoglio, Roberto

2008-05-01

The aim of the study was to define the effectiveness and safety of ultrasound-guided percutaneous radiofrequency (RF) thermal ablation in the treatment of compressive solid benign thyroid nodules. Thirty-one patients not eligible for surgery or radioiodine (131I) treatment underwent RF ablation for benign nodules; a total of 33 nodules were treated (2 patients had 2 nodules treated in the same session): 10 cold nodules and 23 hyperfunctioning. Fourteen patients complained of compressive symptoms. Nodule volume, thyroid function and compressive symptoms were evaluated before treatment and at 1, 3 and 6 mo. Ultrasound-guided RF ablation was performed using a Starbust RITA needle, with nine expandable prongs; total exposure time was 6 to 10 min at 95 degrees C in one area or more of the nodule. Baseline volume (measured at the time of RF ablation) was 27.7 +/- 21.5 mL (mean +/- SD), but significantly decreased during follow-up: 19.2 +/- 16.2 at 1 mo (-32.7%; p < 0.001), 15.9 +/- 14.1 mL at 3 mo (-46.4 %; p < 0.001) and 14.6 +/- 12.6 mL at 6 mo (-50.7%; p < 0.001). After treatment, all patients with cold nodules remained euthyroid: five patients with hot nodules normalized thyroid function, and the remaining sixteen showed a partial remission of hyperthyroidism. Besides a sensation of heat and mild swelling of the neck, no major complications were observed. Improvement in compressive symptoms was reported by 13 patients, with a reduction on severity scale from 6.1 +/- 1.4 to 2.2 +/- 1.9 (p < 0.0001). Radiofrequency was effective and safe in reducing volume by about 50% and compressive symptoms in large benign nodules. Hyperfunction was fully controlled in 24% of patients and partially reduced in the others.

Feline focus: Diagnostic testing for feline thyroid disease: hyperthyroidism.

PubMed

Peterson, Mark E

2013-08-01

In older cats presenting with clinical features of hyperthyroidism, confirming the diagnosis of thyroid disease is usually straightforward. However, the potential for false-negative and false-positive results exists with all thyroid function tests, especially when used for routine screening of large numbers of asymptomatic cats. Therefore, all thyroid function test results must be interpreted in light of the cat's history, clinical signs, and other laboratory findings. If a high serum thyroxine (T4) value is found in a cat that lacks clinical signs of hyperthyroidism, or if hyperthyroidism is suspected in a cat with normal total T4 concentrations, repeating the total T4 analysis, determining the free T4 concentration, or performing thyroid scintigraphy may be needed to confirm the diagnosis.

Thyroid hormonal disturbances related to treatment of hepatitis C with interferon-alpha and ribavirin

PubMed Central

Danilovic, Debora Lucia Seguro; Mendes-Correa, Maria Cassia; Chammas, Maria Cristina; Zambrini, Heverton; Marui, Suemi

2011-01-01

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 examinations, hormonal evaluations, and color-flow Doppler ultrasonography of the thyroid were performed before and during antiviral therapy. RESULTS: Of the patients in our study, 54% had no thyroid disorders associated with the interferon-alpha therapy but showed reduced levels of total T3 along with a decrease in serum alanine aminotransferase. Total T4 levels were also reduced at 3 and 12 months, but free T4 and thyroid stimulating hormone (TSH) levels remained stable. A total of 19% of the subjects had autoimmune interferon-induced thyroiditis, which is characterized by an emerge of antithyroid antibodies or overt hypothyroidism. Additionally, 16% had non-autoimmune thyroiditis, which presents as destructive thyroiditis or subclinical hypothyroidism, and 11% remained in a state of euthyroidism despite the prior existence of antithyroidal antibodies. Thyrotoxicosis with destructive thyroiditis was diagnosed within three months of therapy, and ultrasonography of these patients revealed thyroid shrinkage and discordant change in the vascular patterns. DISCUSSION: Decreases in the total T3 and total T4 levels may be related to improvements in the hepatocellular lesions or inflammatory changes similar to those associated with nonthyroidal illnesses. The immune mechanisms and direct effects of interferon-alpha can be associated with thyroiditis. CONCLUSION: Interferon-alpha and ribavirin induce autoimmune and non-autoimmune thyroiditis and hormonal changes (such as decreased total T3 and total T4 levels), which occur despite stable free T4 and TSH levels. A thyroid hormonal evaluation, including the analysis of the free T4, TSH, and antithyroid antibody levels, should be mandatory before therapy, and an early re-evaluation within three months of treatment is necessary as an appropriate follow-up. PMID:22012048

Thyroid hormonal disturbances related to treatment of hepatitis C with interferon-alpha and ribavirin.

PubMed

Danilovic, Debora Lucia Seguro; Mendes-Correa, Maria Cassia; Chammas, Maria Cristina; Zambrini, Heverton; Marui, Suemi

2011-01-01

To characterize thyroid disturbances induced by interferon-alpha and ribavirin therapy in patients with chronic hepatitis C. Interferon-alpha is used to treat chronic hepatitis C infections. This compound commonly induces both autoimmune and non-autoimmune thyroiditis. We prospectively selected 26 patients with chronic hepatitis C infections. Clinical examinations, hormonal evaluations, and color-flow Doppler ultrasonography of the thyroid were performed before and during antiviral therapy. Of the patients in our study, 54% had no thyroid disorders associated with the interferon-alpha therapy but showed reduced levels of total T3 along with a decrease in serum alanine aminotransferase. Total T4 levels were also reduced at 3 and 12 months, but free T4 and thyroid stimulating hormone (TSH) levels remained stable. A total of 19% of the subjects had autoimmune interferon-induced thyroiditis, which is characterized by an emerge of antithyroid antibodies or overt hypothyroidism. Additionally, 16% had non-autoimmune thyroiditis, which presents as destructive thyroiditis or subclinical hypothyroidism, and 11% remained in a state of euthyroidism despite the prior existence of antithyroidal antibodies. Thyrotoxicosis with destructive thyroiditis was diagnosed within three months of therapy, and ultrasonography of these patients revealed thyroid shrinkage and discordant change in the vascular patterns. Decreases in the total T3 and total T4 levels may be related to improvements in the hepatocellular lesions or inflammatory changes similar to those associated with nonthyroidal illnesses. The immune mechanisms and direct effects of interferon-alpha can be associated with thyroiditis. Interferon-alpha and ribavirin induce autoimmune and non-autoimmune thyroiditis and hormonal changes (such as decreased total T3 and total T4 levels), which occur despite stable free T4 and TSH levels. A thyroid hormonal evaluation, including the analysis of the free T4, TSH, and antithyroid antibody levels, should be mandatory before therapy, and an early re-evaluation within three months of treatment is necessary as an appropriate follow-up.

Trimester specific reference intervals for thyroid function tests in normal Indian pregnant women.

PubMed

Sekhri, Tarun; Juhi, Juhi Agarwal; Wilfred, Reena; Kanwar, Ratnesh S; Sethi, Jyoti; Bhadra, Kuntal; Nair, Sirimavo; Singh, Satveer

2016-01-01

Accurate assessment of thyroid function during pregnancy is critical, for initiation of thyroid hormone therapy, as well as for adjustment of thyroid hormone dose in hypothyroid cases. We evaluated pregnant women who had no past history of thyroid disorders and studied their thyroid function in each trimester. 86 normal pregnant women in the first trimester of pregnancy were selected for setting reference intervals. All were healthy, euthyroid and negative for thyroid peroxidase antibody (TPOAb). These women were serially followed throughout pregnancy. 124 normal nonpregnant subjects were selected for comparison. Thyrotropin (TSH), free thyroxine (FT4), free triiodothyronine (FT3) and anti-TPO were measured using Roche Elecsys 1010 analyzer. Urinary iodine content was determined by simple microplate method. The 2.5th and 97.5th percentiles were calculated as the reference intervals for thyroid hormone levels during each trimester. SPSS (version 14.0, SPSS Inc., Chicago, IL, USA) was used for data processing and analysis. The reference intervals for the first, second and third trimesters for the following parameters: TSH 0.09-6.65, 0.51-6.66, 0.91-4.86 µIU/mL, FT4 9.81-18.53, 8.52-19.43, 7.39-18.28 pM/L and FT3 3.1-6.35, 2.39-5.12, 2.57-5.68 pM/L respectively. Thyroid hormone concentrations significantly differed during pregnancy at different stages of gestation. The pregnant women in the study had median urinary iodine concentration of 150-200 µg/l during each trimester. The trimester-specific reference intervals for thyroid tests during pregnancy have been established for pregnant Indian women serially followed during pregnancy using 2.5th and 97.5th percentiles.

Thyroid disorders in patients treated with radiotherapy for head-and-neck cancer: A retrospective analysis of seventy-three patients

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alterio, Daniela; Jereczek-Fossa, Barbara Alicja; University of Milan, Milan

2007-01-01

Purpose: To evaluate the incidence of thyroid disorders and dose distribution to the thyroid in patients treated with radiotherapy for head-and-neck carcinomas. Methods and Materials: A retrospective evaluation of data from 73 patients treated for head-and-neck cancers in our department was performed. Thyroid function was evaluated mainly by the measurement of thyrotropin (thyroid stimulating hormone [TSH]). A retrospective analysis of treatment plans was performed for 57 patients. Percentages of thyroid glandular volume absorbing 10, 30, and 50 Gy (V10, V30, and V50 respectively) were considered for statistical analysis. Results: A majority of patients (61%) had a normal thyroid function whereasmore » 19 patients (26%) had hypothyroidism. Mean thyroid volume was 30.39 cc. Point 3 (located at isthmus) absorbed lower doses compared with other points (p < 0.0001). Median values of V10, V30, and V50 were 92% (range, 57-100%), 75% (range, 28.5-100%), and 35% (range, 3-83%) respectively. Gender was associated with toxicity (presence of any kind of thyroid disorders) (p < 0.05), with females displaying higher levels of TSHr (relative TSH = patient's value/maximum value of the laboratory range) (p = 0.0005) and smaller thyroid volume (p 0.0012) compared with male population. TSHr values were associated with thyroid volume, and the presence of midline shielding block in the anterior field was associated with relative free thyroxine (FT4r = patient's value/maximum value of the laboratory range) values. Conclusions: Gender and thyroid volume seem to play an important role in the occurrence of thyroid toxicity, but further studies on dose-effect relationship for radiotherapy-induced thyroid toxicity are needed.« less

The relationship of deiodinase 1 genotype and thyroid function to lifetime history of major depression in three independent populations.

PubMed

Philibert, Robert A; Beach, Steven R H; Gunter, Tracy D; Todorov, Alexandre A; Brody, Gene H; Vijayendran, Meeshanthini; Elliott, Lilly; Hollenbeck, Nancy; Russell, Daniel; Cutrona, Carolyn

2011-07-01

Major depression (MD) is often associated with disturbances of the hypothalamic/pituitary/thyroid (HPT) axis. Unfortunately, whether this association is secondary to common underlying genetic variation or whether the MD-associated disturbances in HPT function are chronic or state-dependent is unknown. To examine these questions, we genotyped 12 single nucleotide polymorphisms identified in previous genome wide association analyses of thyroid function in DNA contributed by 1,555 subjects from three longitudinal ethnically diverse studies that are well-characterized for lifetime MD and thyroid function. We then examined associations between genetic variants and key outcomes of thyroid stimulating hormone, free thyroxine (FT4) and depression. We confirmed prior findings that two variants in deiodinase 1 (DIO1), including a variant in the 3'UTR of DIO1 (rs11206244), were associated with altered FT4 levels in both White and African American subjects. We also found that rs11206244 genotype was associated with lifetime MD in White female subjects, in particular those from high-risk cohorts. However, we found no association of current FT4 levels with lifetime MD in either ethnic group. We conclude that genetic variation influencing thyroid function is a risk factor for MD. Given the evidence from prior studies, further investigations of role of HPT variation in etiology and treatment of MD are indicated. Copyright © 2011 Wiley-Liss, Inc.

The Relationship of Deiodinase 1 Genotype and Thyroid Function to Lifetime History of Major Depression in Three Independent Populations

PubMed Central

Philibert, Robert A.; Beach, Steven R. H.; Gunter, Tracy D.; Todorov, Alexandre A.; Brody, Gene H.; Vijayendran, Meeshanthini; Elliott, Lilly; Hollenbeck, Nancy; Russell, Daniel; Cutrona, Carolyn

2011-01-01

Major depression (MD) is often associated with disturbances of the hypothalamic/pituitary/thyroid (HPT) axis. Unfortunately, whether this association is secondary to common underlying genetic variation or whether the MD-associated disturbances in HPT function are chronic or state-dependent is unknown. To examine these questions, we genotyped 12 single nucleotide polymorphisms identified in previous genome wide association analyses of thyroid function in DNA contributed by 1555 subjects from three longitudinal ethnically diverse studies that are well-characterized for lifetime major depression and thyroid function. We then examined associations between genetic variants and key outcomes of thyroid stimulating hormone (TSH), free thyroxine (FT4) and depression. We confirmed prior findings that two variants in deiodinase 1 (DIO1), including a variant in the 3’ UTR of DIO1 (rs11206244), were associated with altered free thyroxine (FT4) levels in both White and African American subjects. We also found that rs11206244 genotype was associated with lifetime MD in White female subjects, in particular those from high-risk cohorts. However, we found no association of current FT4 levels with lifetime MD in either ethnic group. We conclude that genetic variation influencing thyroid function is a risk factor for MD. Given the evidence from prior studies, further investigations of role of HPT variation in etiology and treatment of MD are indicated. PMID:21563302

Relationship between blood cadmium, lead, and serum thyroid measures in US adults - the National Health and Nutrition Examination Survey (NHANES) 2007-2010.

PubMed

Luo, Juhua; Hendryx, Michael

2014-04-01

Experimental studies have shown that both cadmium (Cd) and lead have potent endocrine disrupting activity. However, studies on whether these heavy metals disrupt thyroid system in humans, especially in general populations with low levels of exposure, are sparse. The study analyzed 6,231 participants aged 20 and older with measurements from 2007-2010 of the National Health and Nutrition Examination Survey (NHANES) to investigate whether whole blood Cd and lead level are associated with serum thyroid hormones measures. Our study suggests that thyroid function may be disrupted by both Cd and lead exposures in the general population and the specific roles of Cd and lead exposure on thyroid axis may differ by sex. However, the mechanisms by which these heavy metals may disrupt thyroid system function in general population needs to be further investigated.

Estimating Margin of Exposure to Thyroid Peroxidase Inhibitors Using High-throughput In Vitro Data, High-throughput Exposure Modeling, and Physiologically-Based Pharmacokinetic/Pharmacodynamic Modeling

EPA Science Inventory

Some pharmaceuticals and environmental chemicals bind the thyroid peroxidase (TPO) enzyme and disrupt thyroid hormone production. The potential for TPO inhibition is a function of both the binding affinity and concentration of the chemical within the thyroid gland. The former can...

The thyroid hormone triiodothyronine controls macrophage maturation and functions: protective role during inflammation.

PubMed

Perrotta, Cristiana; Buldorini, Marcella; Assi, Emma; Cazzato, Denise; De Palma, Clara; Clementi, Emilio; Cervia, Davide

2014-01-01

The endocrine system participates in regulating macrophage maturation, although little is known about the modulating role of the thyroid hormones. In vitro results demonstrate a negative role of one such hormone, triiodothyronine (T3), in triggering the differentiation of bone marrow-derived monocytes into unpolarized macrophages. T3-induced macrophages displayed a classically activated (M1) signature. A T3-induced M1-priming effect was also observed on polarized macrophages because T3 reverses alternatively activated (M2) activation, whereas it enhances that of M1 cells. In vivo, circulating T3 increased the content of the resident macrophages in the peritoneal cavity, whereas it reduced the content of the recruited monocyte-derived cells. Of interest, T3 significantly protected mice against endotoxemia induced by lipopolysaccharide i.p. injection; in these damaged animals, decreased T3 levels increased the recruited (potentially damaging) cells, whereas restoring T3 levels decreased recruited and increased resident (potentially beneficial) cells. These data suggest that the anti-inflammatory effect of T3 is coupled to the modulation of peritoneal macrophage content, in a context not fully explained by the M1/M2 framework. Thyroid hormone receptor expression analysis and the use of different thyroid hormone receptor antagonists suggest thyroid hormone receptor β1 as the major player mediating T3 effects on macrophages. The novel homeostatic link between thyroid hormones and the pathophysiological role of macrophages opens new perspectives on the interactions between the endocrine and immune systems. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

Congenital hypothyroidism, dwarfism, and hearing impairment caused by a missense mutation in the mouse dual oxidase 2 gene, Duox2.

PubMed

Johnson, Kenneth R; Marden, Coleen C; Ward-Bailey, Patricia; Gagnon, Leona H; Bronson, Roderick T; Donahue, Leah Rae

2007-07-01

Dual oxidases generate the hydrogen peroxide needed by thyroid peroxidase for the incorporation of iodine into thyroglobulin, an essential step in thyroid hormone synthesis. Mutations in the human dual oxidase 2 gene, DUOX2, have been shown to underlie several cases of congenital hypothyroidism. We report here the first mouse Duox2 mutation, which provides a new genetic model for studying the specific function of DUOX2 in the thyroid gland and in other organ systems where it is hypothesized to play a role. We mapped the new spontaneous mouse mutation to chromosome 2 and identified it as a T>G base pair change in exon 16 of Duox2. The mutation changes a highly conserved valine to glycine at amino acid position 674 (V674G) and was named "thyroid dyshormonogenesis" (symbol thyd) to signify a defect in thyroid hormone synthesis. Thyroid glands of mutant mice are goitrous and contain few normal follicles, and anterior pituitaries are dysplastic. Serum T(4) in homozygotes is about one-tenth the level of controls and is accompanied by a more than 100-fold increase in TSH. The weight of adult mutant mice is approximately half that of littermate controls, and serum IGF-I is reduced. The cochleae of mutant mice exhibit abnormalities characteristic of hypothyroidism, including a delayed formation of the inner sulcus and tunnel of Corti and an abnormally thickened tectorial membrane. Hearing thresholds of adult mutant mice are on average 50-60 decibels (dB) above those of controls.

[Severe hyperlipidemia, secondary to hypothyroidism due to atrophic thyroiditis in a girl].

PubMed

Pacín, Mirta

2009-02-01

We present a 5 years 8 months old girl with severe hyperlipidemia (high total cholesterol, and low density lipoprotein values, and also, ectopic fat pericardial deposit). She was treated with diet and cholestyramine, without diagnosis of her disease etiology. Growth detention, weight loss, retarded bone age and clinical signs of hypometabolism were recorded. Thyroid profile confirms hypothyroidism diagnosis. Based on positive anti-thyroid antibodies and clearly reduced thyroid volume, a diagnosis of autoimmune atrophic thyroiditis was made, a very unusual pathology in early infancy. Linear growth was affected by late diagnosis.

The role of polyhalogenated aromatic hydrocarbons on thyroid hormone disruption and cognitive function: a review.

PubMed

Builee, T L; Hatherill, J R

2004-11-01

Thyroid hormones (TH) are essential to normal brain development, influencing behavior and cognitive function in both adult and children. It is suggested that conditions found in TH abnormalities such as hypothyroidism, hyperthyroidism and generalized resistance to thyroid hormone (GRTH) share symptomatic behavioral impulses found in cases of attention deficit hyperactivity disorder (ADHD) and other cognitive disorders. Disrupters of TH are various and prevalent in the environment. This paper reviews the mechanisms of TH disruption caused by the general class of polyhalogenated aromatic hydrocarbons (PHAH)'s acting as thyroid disrupters (TD). PHAHs influence the hypothalamus-pituitary-thyroid (HPT) axis, as mimicry agents affecting synthesis and secretion of TH. Exposure to PHAH induces liver microsomal enzymes UDP-glucuronosyltransferase (UGT) resulting in accelerated clearance of TH. PHAHs can compromise function of transport and receptor binding proteins such as transthyretin and aryl hydrocarbon receptors (Ahr). Glucose metabolism and catecholamine synthesis are disrupted in the brain by the presence of PHAH. Further, PHAH can alter brain growth and development by perturbing cytoskeletal formation, thereby affecting neuronal migration, elongation and branching. The complex relationships between PHAH and cognitive function are examined in regard to the disruption of T4 regulation in the hypothalamus-pituitary-thyroid axis, blood, brain, neurons, liver and pre and postnatal development.

Effect of functionally significant deiodinase single nucleotide polymorphisms on drinking behavior in alcohol dependence: an exploratory investigation

PubMed Central

Lee, MR; Schwandt, ML; Bollinger, JW; Dias, AA; Oot, EN; Goldman, D; Hodgkinson, CA; Leggio, L

2016-01-01

Background Abnormalities of the hypothalamic-pituitary-thyroid (HPT) axis have been reported in alcoholism, however, there is no definitive agreement on the specific thyroid abnormalities and their underlying mechanisms in alcohol dependence (AD). The biological activity of thyroid hormones or the availability of T3 is regulated by the three deiodinase enzymes D1, D2 and D3. In the context of alcohol use, functionally significant single nucleotide polymorphisms (SNP’s) of these deiodinase genes may play a role in HPT dysfunction. Methods The present study explored the effect of three functionally significant SNP’s (D1: rs2235544, D2: rs225014 and rs12885300) of deiodinase genes on drinking behavior and thyroid stimulating hormone (TSH) levels in alcohol dependent (N=521) and control subjects (N=228). Results Rs225014 was associated with significant differences in the amount of naturalistic alcohol drinking assessed by the Timeline Follow-Back (TLFB). Alcohol-dependent subjects had significantly higher thyroid stimulating hormone levels compared to controls; however, there was no effect of genotype on TSH levels for either group. Conclusions These findings extend previous studies on thyroid dysfunction in alcoholism and provide novel, albeit preliminary, information by linking functionally significant genetic polymorphisms of the deiodinase enzymes with alcohol drinking behavior. PMID:26207529

Thyroid Hormones and Growth in Health and Disease

PubMed Central

Tarım, Ömer

2011-01-01

Thyroid hormones regulate growth by several mechanisms. In addition to their negative feedback effect on the stimulatory hormones thyrotropin-releasing hormone (TRH) and thyrotropin (TSH), thyroid hormones also regulate their receptors in various physiological and pathological conditions. Up-regulation and down-regulation of the thyroid receptors fine-tune the biological effects exerted by the thyroid hormones. Interestingly, the deiodinase enzyme system is another intrinsic regulator of thyroid physiology that adjusts the availability of thyroid hormones to the tissues, which is essential for normal growth and development. Almost all chronic diseases of childhood impair growth and development. Every disease may have a unique mechanism to halt linear growth, but reduced serum concentration or diminished local availability of thyroid hormones seems to be a common pathway. Therefore, the effects of systemic diseases on thyroid physiology must be taken into consideration in the evaluation of growth retardation in affected children. Conflict of interest:None declared. PMID:21750631

The hippocampal formation: morphological changes induced by thyroid, gonadal and adrenal hormones.

PubMed

Gould, E; Woolley, C S; McEwen, B S

1991-01-01

The hippocampal formation is of considerable interest due to its proposed role in a number of important functions, including learning and memory processes. Manipulations of thyroid, gonadal and adrenal hormones have been shown to influence hippocampal physiology as well as learning and memory. The cellular events which underlie these hormone-induced functional changes are largely unexplored. However, studies suggest that hormonal manipulations during development and in adulthood result in dramatic morphological changes within the hippocampal formation. Because neuronal physiology has been suggested to depend upon neuronal morphology, we have been determining the morphologic sensitivity of hippocampal neurons to thyroid and steroid hormones in an effort to elucidate possible structural mechanisms to account for differences in hippocampal function. In this review, hormone-induced structural changes in the developing and adult hippocampal formation are discussed, with particular emphasis on their functional relevance. Sex differences, as well as the developmental effects of thyroid hormone and glucocorticoids, are described. Moreover, the effects of ovarian steroids, thyroid hormone and glucocorticoids on neuronal morphology in the hippocampal formation of the adult rat are reviewed. These hormone-induced structural changes may account, at least in part, for previously reported hormone-induced changes in hippocampal function.

Subclinical hyperthyroidism: clinical features and treatment options.

PubMed

Biondi, Bernadette; Palmieri, Emiliano Antonio; Klain, Michele; Schlumberger, Martin; Filetti, Sebastiano; Lombardi, Gaetano

2005-01-01

Subclinical hyperthyroidism appears to be a common disorder. It may be caused by exogenous or endogenous factors: excessive TSH suppressive therapy with L-thyroxine (L-T4) for benign thyroid nodular disease, differentiated thyroid cancer, or hormone over-replacement in patients with hypothyroidism are the most frequent causes. Consistent evidence indicates that 'subclinical' hyperthyroidism reduces the quality of life, affecting both the psycho and somatic components of well-being, and produces relevant signs and symptoms of excessive thyroid hormone action, often mimicking adrenergic overactivity. Subclinical hyperthyroidism exerts many significant effects on the cardiovascular system; it is usually associated with a higher heart rate and a higher risk of supraventricular arrhythmias, and with an increased left ventricular mass, often accompanied by an impaired diastolic function and sometimes by a reduced systolic performance on effort and decreased exercise tolerance. It is well known that these abnormalities usually precede the onset of a more severe cardiovascular disease, thus potentially contributing to the increased cardiovascular morbidity and mortality observed in these patients. In addition, it is becoming increasingly apparent that subclinical hyperthyroidism may accelerate the development of osteoporosis and hence increased bone vulnerability to trauma, particularly in postmenopausal women with a pre-existing predisposition. Subclinical hyperthyroidism and its related clinical manifestations are reversible and may be prevented by timely treatment.

Is dietary nitrate/nitrite exposure a risk factor for development of thyroid abnormality? A systematic review and meta-analysis.

PubMed

Bahadoran, Zahra; Mirmiran, Parvin; Ghasemi, Asghar; Kabir, Ali; Azizi, Fereidoun; Hadaegh, Farzad

2015-05-01

The potential effects of inorganic nitrate/nitrite on global health are a much debated issue. In addition to possible methemoglobinemia and carcinogenic properties, anti-thyroid effects of nitrate/nitrite have been suggested. Considering the growing significance of nitrate/nitrite and since there is no comprehensive review in data available, clarifying the effect of nitrate/nitrite on thyroid disorder outcomes is essential. Therefore, we conducted this systematic review of experimental and clinical studies, and a meta-analysis of relevant cohort and cross-sectional studies investigating the association of nitrate/nitrite exposure and thyroid function. Most animal studies show that high exposure (~10-600 times of acceptable daily intake) to nitrate/nitrite induces anti-thyroid effects, including decreased serum level of thyroid hormones and histomorphological changes in thyroid gland; however no similar observations have been documented in humans. Based on our meta-analysis, no significant association was observed between nitrate exposure and the risk of thyroid cancer, hyper- and hypothyroidism; findings from three cohort studies however showed a significant association between higher exposure to nitrite and the risk of thyroid cancer (risk = 1.48, 95% confidence interval = 1.09-2.02, P = 0.012). Additional research is needed to clarify the association between nitrate/nitrite exposures and both thyroid function and cancer. Copyright © 2015 Elsevier Inc. All rights reserved.

The effect of lead intoxication on endocrine functions.

PubMed

Doumouchtsis, K K; Doumouchtsis, S K; Doumouchtsis, E K; Perrea, D N

2009-02-01

Studies on the effects of lead on the endocrine system are mainly based on occupationally lead-exposed workers and experimental animal models. Although evidence is conflicting, it has been reported that accumulation of lead affects the majority of the endocrine glands. In particular, it appears to have an effect on the hypothalamic-pituitary axis causing blunted TSH, GH, and FSH/LH responses to TRH, GHRH, and GnRH stimulation, respectively. Suppressed GH release has been reported, probably caused by reduced synthesis of GHRH, inhibition of GHRH release or reduced somatotrope responsiveness. Higher levels of PRL in lead intoxication have been reported. In short-term lead-exposed individuals, high LH and FSH levels are usually associated to normal testosterone concentrations, whereas in long-term exposed individuals' low testosterone levels do not induce high LH and FSH concentrations. These findings suggest that lead initially causes some subclinical testicular damage, followed by hypothalamic or pituitary disturbance when longer periods of exposure take place. Similarly, lead accumulates in granulosa cells of the ovary, causing delays in growth and pubertal development and reduced fertility in females. In the parenchyma of adrenals histological and cytological changes are demonstrated, causing changes in plasma basal and stress-mediated corticosterone concentrations and reduced cytosolic and nuclear glucocorticoid receptor binding. Thyroid hormone kinetics are also affected. Central defect of the thyroid axis or an alteration in T4 metabolism or binding to proteins may be involved in derangements in thyroid hormone action. Lead toxicity involves alterations on calcitropic hormones' homeostasis, which increase the risk of skeletal disorders.

Loss of p53 promotes anaplasia and local invasion in ret/PTC1-induced thyroid carcinomas.

PubMed

La Perle, K M; Jhiang, S M; Capen, C C

2000-08-01

Papillary thyroid carcinomas in humans are associated with the ret/PTC oncogene and, following loss of p53 function, may progress to anaplastic carcinomas. Mice with thyroid-targeted expression of ret/PTC1 developed papillary thyroid carcinomas that were minimally invasive and did not metastasize. These mice were crossed with p53-/- mice to investigate whether loss of p53 would promote anaplasia and metastasis of ret/PTC1-induced thyroid tumors. The majority of p53-/- mice died or were euthanized by 17 weeks of age due to the development of thymic lymphomas, soft tissue sarcomas, and testicular teratomas. All ret/PTC1 mice developed thyroid carcinomas, but tumors in p53-/- mice were more anaplastic, larger in diameter, more invasive, and had a higher mitotic index than tumors in p53+/+ and p53+/- mice. Thyroid tumors did not metastasize in any of the experimental p53+/+ and p53+/- mice

Association between thyroid hormones and TRAIL.

PubMed

Bernardi, Stella; Bossi, Fleur; Toffoli, Barbara; Giudici, Fabiola; Bramante, Alessandra; Furlanis, Giulia; Stenner, Elisabetta; Secchiero, Paola; Zauli, Giorgio; Carretta, Renzo; Fabris, Bruno

2017-11-01

Recent studies suggest that a circulating protein called TRAIL (TNF-related apoptosis-inducing ligand) might have a role in the regulation of body weight and metabolism. Interestingly, thyroid hormones seem to increase TRAIL tissue expression. This study aimed at evaluating whether overt thyroid disorders affected circulating TRAIL levels. TRAIL circulating levels were measured in euthyroid, hyperthyroid, and hypothyroid patients before and after thyroid function normalization. Univariate and multivariate analyses were performed to evaluate the correlation between thyroid hormones and TRAIL. Then, the stimulatory effect of both triiodothyronine (T3) and thyroxine (T4) on TRAIL was evaluated in vitro on peripheral blood mononuclear cells. Circulating levels of TRAIL significantly increased in hyperthyroid and decreased in hypothyroid patients as compared to controls. Once thyroid function was restored, TRAIL levels normalized. There was an independent association between TRAIL and both fT3 and fT4. Consistent with these findings, T3 and T4 stimulated TRAIL release in vitro. Here we show that thyroid hormones are associated with TRAIL expression in vivo and stimulate TRAIL expression in vitro. Given the overlap between the metabolic effects of thyroid hormones and TRAIL, this work sheds light on the possibility that TRAIL might be one of the molecules mediating thyroid hormones peripheral effects. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Fluoride exposure and indicators of thyroid functioning in the Canadian population: implications for community water fluoridation.

PubMed

Barberio, Amanda M; Hosein, F Shaun; Quiñonez, Carlos; McLaren, Lindsay

2017-10-01

There are concerns that altered thyroid functioning could be the result of ingesting too much fluoride. Community water fluoridation (CWF) is an important source of fluoride exposure. Our objectives were to examine the association between fluoride exposure and (1) diagnosis of a thyroid condition and (2) indicators of thyroid functioning among a national population-based sample of Canadians. We analysed data from Cycles 2 and 3 of the Canadian Health Measures Survey (CHMS). Logistic regression was used to assess associations between fluoride from urine and tap water samples and the diagnosis of a thyroid condition. Multinomial logistic regression was used to examine the relationship between fluoride exposure and thyroid-stimulating hormone (TSH) level (low/normal/high). Other available variables permitted additional exploratory analyses among the subset of participants for whom we could discern some fluoride exposure from drinking water and/or dental products. There was no evidence of a relationship between fluoride exposure (from urine and tap water) and the diagnosis of a thyroid condition. There was no statistically significant association between fluoride exposure and abnormal (low or high) TSH levels relative to normal TSH levels. Rerunning the models with the sample constrained to the subset of participants for whom we could discern some source(s) of fluoride exposure from drinking water and/or dental products revealed no significant associations. These analyses suggest that, at the population level, fluoride exposure is not associated with impaired thyroid functioning in a time and place where multiple sources of fluoride exposure, including CWF, exist. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Hypothyrodism in male patients: a descriptive, observational and cross-sectional study in a series of 260 men.

PubMed

Iglesias, Pedro; Díez, Juan J

2008-10-01

Several aspects of thyroid dysfunction have not been fully characterized in large series of male patients. Our aim was to investigate the etiology and clinical features of hypothyroidism and assess the adequacy of replacement therapy in men attending an endocrinology clinic. We studied a group of 260 men (mean (+/-standard deviation) age 58.3 +/- 16.1 years) periodically seen because of thyroid hypofunction. We evaluated the etiology of hypothyroidism, presence or absence of goiter, time of evolution from diagnosis, current thyroid autoimmunity and thyroid functional status, and adequacy of disease control. Overt hypothyroidism was found in 182 (70.0%) and subclinical hypothyroidism in 78 (30.0%) patients. Autoimmune thyroiditis was the most frequent etiology (n = 107, 41.2%). Of these, 96 (89.7%) showed no goiter. Thyroid peroxidase antibodies were measured in 238 patients, being positive in 129 (54.2%) and negative in 109 (45.8%) patients. After excluding patients with thyroid carcinoma and those with recently diagnosed hypothyroidism, we found an adequate control of thyroid function, ie, normal thyrotropin and free thyroxine levels, in 95 patients (64.2%). Adequacy of treatment did not show any relationship with age, age at diagnosis, etiology, and autoimmune status. However, adequacy was significantly related to the degree of thyroid hypofunction (P < 0.001) and to the duration of disease (P < 0.01). We conclude that autoimmune thyroiditis, mainly the nongoitrous form, and postoperative hypothyroidism are the foremost causes of thyroid hypofunction in male patients. Adequacy of replacement treatment seems to be mainly related to the degree of thyroid hypofunction and the time from starting therapy.

Selenium and its relationship with selenoprotein P and glutathione peroxidase in children and adolescents with Hashimoto's thyroiditis and hypothyroidism.

PubMed

Nourbakhsh, Mitra; Ahmadpour, Fatemeh; Chahardoli, Behnam; Malekpour-Dehkordi, Zahra; Nourbakhsh, Mona; Hosseini-Fard, Seyed Reza; Doustimotlagh, Amirhossein; Golestani, Abolfazl; Razzaghy-Azar, Maryam

2016-03-01

The essential trace element selenium (Se) is required for thyroid hormone synthesis and metabolism. Selenoproteins contain selenocysteine and are responsible for biological functions of selenium. Glutathione peroxidase (GPx) is one of the major selenoproteins which protects the thyroid cells from oxidative damage. Selenoprotein P (SePP) is considered as the plasma selenium transporter to tissues. The aim of this study was to evaluate serum Se and SePP levels, and GPx activity in erythrocytes of children and adolescents with treated Hashimoto's thyroiditis, hypothyroidism, and normal subjects. Blood samples were collected from 32 patients with Hashimoto's thyroiditis, 20 with hypothyroidism, and 25 matched normal subjects. All the patients were under treatment with levothyroxine and at the time of analysis all of the thyroid function tests were normal. GPx enzyme activity was measured by spectrophotometry at 340 nm. Serum selenium levels were measured by high-resolution continuum source graphite furnace atomic absorption. SePP, TPOAb (anti-thyroid peroxidase antibody), and TgAb (anti-thyroglobulin antibody) were determined by ELISA kits. T4, T3, T3 uptake and TSH were also measured. Neither GPx activity nor SePP levels were significantly different in patients with Hashimoto's thyroiditis or hypothyroidism compared to normal subjects. Although GPx and SePP were both lower in patients with hypothyroidism compared to those with Hashimoto's thyroiditis and normal subjects but the difference was not significant. Serum Se levels also did not differ significantly in patients and normal subjects. We did not find any correlation between GPx or SePP with TPOAb or TgAb but SePP was significantly correlated with Se. Results show that in patients with Hashimoto's thyroiditis or hypothyroidism who have been under treatment with levothyroxine and have normal thyroid function tests, the GPx, SePP and Se levels are not significantly different. Copyright © 2015 Elsevier GmbH. All rights reserved.

Hypothyroidism After Head-and-Neck Radiotherapy in Children and Adolescents: Preliminary Results of the 'Registry for the Evaluation of Side Effects After Radiotherapy in Childhood and Adolescence' (RiSK)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boelling, Tobias, E-mail: Tobias.Boelling@uni-muenster.de; Department of Radiotherapy, Paracelsus Clinic Osnabrueck, Osnabrueck; Geisenheiser, Alina

Purpose: The 'Registry for the Evaluation of Side Effects After Radiotherapy in Childhood and Adolescence' (RiSK) has been established to prospectively characterize dose-volume effects of radiation in terms of side effects. The aim of this analysis was to characterize the function of the thyroid gland after radiotherapy to the head-and-neck region in children and adolescents. Methods and Materials: Detailed information regarding radiation doses to at-risk organs has been collected across Germany since 2001. Thyroid function was evaluated by blood value examinations of thyroid-stimulating hormone, triiodothyronine, and thyroxine. Information regarding thyroid hormone substitution was requested from the treating physicians. Results: Untilmore » May 2009, 1,086 patients from 62 centers were recruited, including 404 patients (median age, 10.9 years) who had received radiotherapy to the thyroid gland and/or hypophysis. Follow-up information was available for 264 patients (60.9%; median follow-up, 40 months), with 60 patients (22.7%) showing pathologic values. In comparison to patients treated with prophylactic cranial irradiation (median dose, 12 Gy), patients with radiation doses of 15 to 25 Gy to the thyroid gland had a hazard ratio of 3.072 (p = 0.002) for the development of pathologic thyroid blood values. Patients with greater than 25 Gy to the thyroid gland and patients who underwent craniospinal irradiation had hazard ratios of 3.768 (p = 0.009) and 5.674 (p < 0.001), respectively. The cumulative incidence of thyroid hormone substitution therapy did not differ between defined subgroups. Conclusions: Radiation-induced thyroid function impairment, including damage to the thyroid gland and/or hypophysis, can frequently be observed after radiotherapy in children. A structured follow-up examination is advised.« less

Triiodothyronine Facilitates Weaning From Extracorporeal Membrane Oxygenation by Improved Mitochondrial Substrate Utilization

PubMed Central

Files, Matthew D.; Kajimoto, Masaki; O'Kelly Priddy, Colleen M.; Ledee, Dolena R.; Xu, Chun; Des Rosiers, Christine; Isern, Nancy; Portman, Michael A.

2014-01-01

Background Extracorporeal membrane oxygenation (ECMO) provides a bridge to recovery after myocardial injury in infants and children, yet morbidity and mortality remain high. Weaning from the circuit requires adequate cardiac contractile function, which can be impaired by metabolic disturbances induced either by ischemia‐reperfusion and/or by ECMO. We tested the hypothesis that although ECMO partially ameliorates metabolic abnormalities induced by ischemia‐reperfusion, these abnormalities persist or recur with weaning. We also determined if thyroid hormone supplementation (triiodothyronine) during ECMO improves oxidative metabolism and cardiac function. Methods and Results Neonatal piglets underwent transient coronary ischemia to induce cardiac injury then were separated into 4 groups based on loading status. Piglets without coronary ischemia served as controls. We infused into the left coronary artery [2‐13C]pyruvate and [13C6, 15N]l‐leucine to evaluate oxidative metabolism by gas chromatography‐mass spectroscopy and nuclear magnetic resonance methods. ECMO improved survival, increased oxidative substrate contribution through pyruvate dehydrogenase, reduced succinate and fumarate accumulation, and ameliorated ATP depletion induced by ischemia. The functional and metabolic benefit of ECMO was lost with weaning, yet triiodothyronine supplementation during ECMO restored function, increased relative pyruvate dehydrogenase flux, reduced succinate and fumarate, and preserved ATP stores. Conclusions Although ECMO provides metabolic rest by decreasing energy demand, metabolic impairments persist, and are exacerbated with weaning. Treating ECMO‐induced thyroid depression with triiodothyronine improves substrate flux, myocardial oxidative capacity and cardiac contractile function. This translational model suggests that metabolic targeting can improve weaning. PMID:24650924

Triiodothyronine facilitates weaning from extracorporeal membrane oxygenation by improved mitochondrial substrate utilization.

PubMed

Files, Matthew D; Kajimoto, Masaki; O'Kelly Priddy, Colleen M; Ledee, Dolena R; Xu, Chun; Des Rosiers, Christine; Isern, Nancy; Portman, Michael A

2014-03-20

Extracorporeal membrane oxygenation (ECMO) provides a bridge to recovery after myocardial injury in infants and children, yet morbidity and mortality remain high. Weaning from the circuit requires adequate cardiac contractile function, which can be impaired by metabolic disturbances induced either by ischemia-reperfusion and/or by ECMO. We tested the hypothesis that although ECMO partially ameliorates metabolic abnormalities induced by ischemia-reperfusion, these abnormalities persist or recur with weaning. We also determined if thyroid hormone supplementation (triiodothyronine) during ECMO improves oxidative metabolism and cardiac function. Neonatal piglets underwent transient coronary ischemia to induce cardiac injury then were separated into 4 groups based on loading status. Piglets without coronary ischemia served as controls. We infused into the left coronary artery [2-(13)C]pyruvate and [(13)C6, (15)N]l-leucine to evaluate oxidative metabolism by gas chromatography-mass spectroscopy and nuclear magnetic resonance methods. ECMO improved survival, increased oxidative substrate contribution through pyruvate dehydrogenase, reduced succinate and fumarate accumulation, and ameliorated ATP depletion induced by ischemia. The functional and metabolic benefit of ECMO was lost with weaning, yet triiodothyronine supplementation during ECMO restored function, increased relative pyruvate dehydrogenase flux, reduced succinate and fumarate, and preserved ATP stores. Although ECMO provides metabolic rest by decreasing energy demand, metabolic impairments persist, and are exacerbated with weaning. Treating ECMO-induced thyroid depression with triiodothyronine improves substrate flux, myocardial oxidative capacity and cardiac contractile function. This translational model suggests that metabolic targeting can improve weaning.

Changes in the role of the thyroid axis during metamorphosis of the Japanese eel, Anguilla japonica.

PubMed

Sudo, Ryusuke; Okamura, Akihiro; Kuroki, Mari; Tsukamoto, Katsumi

2014-08-01

To clarify the role of thyroid function during metamorphosis from leptocephalus to glass eel in the Japanese eel, we examined the histology of the thyroid gland and measured whole-body concentrations of thyroid hormones, thyroxine (T4) and triiodothyronine (T3), and thyroid stimulating hormone β-subunit TSH (TSHβ) mRNA expression levels in five stages of artificially hatched eels (leptocephalus, early-metamorphosis, late-metamorphosis, glass eel, and elver). During metamorphosis, the inner colloid of thyroid follicles showed positive immunoreactivity for T4, and both T4 and T3 levels were significantly increased, whereas a small peak of TSHβ mRNA level was observed at the early-metamorphosis stage. Similarly, TSHβ mRNA levels were highest in the glass eel stage, and then decreased markedly in the elver stage. In contrast to TSHβ mRNA expression, thyroid hormones (both T4 and T3) increased further from the glass eel to elver stages. These results indicated that thyroid function in the Japanese eel was active both during and after metamorphosis. Therefore, the thyrotropic axis may play important roles not only in metamorphosis but also in subsequent inshore or upstream migrations. © 2014 Wiley Periodicals, Inc.

Functioning and nonfunctioning thyroid adenomas involve different molecular pathogenetic mechanisms.

PubMed

Tonacchera, M; Vitti, P; Agretti, P; Ceccarini, G; Perri, A; Cavaliere, R; Mazzi, B; Naccarato, A G; Viacava, P; Miccoli, P; Pinchera, A; Chiovato, L

1999-11-01

The molecular biology of follicular cell growth in thyroid nodules is still poorly understood. Because gain-of-function (activating) mutations of the thyroid-stimulating hormone receptor (TShR) and/or Gs alpha genes may confer TSh-independent growth advantage to neoplastic thyroid cells, we searched for somatic mutations of these genes in a series of hyperfunctioning and nonfunctioning follicular thyroid adenomas specifically selected for their homogeneous gross anatomy (single nodule in an otherwise normal thyroid gland). TShR gene mutations were identified by direct sequencing of exons 9 and 10 of the TShR gene in genomic DNA obtained from surgical specimens. Codons 201 and 227 of the Gs alpha gene were also analyzed. At histology, all hyperfunctioning nodules and 13 of 15 nonfunctioning nodules were diagnosed as follicular adenomas. Two nonfunctioning thyroid nodules, although showing a prevalent microfollicular pattern of growth, had histological features indicating malignant transformation (a minimally invasive follicular carcinoma and a focal papillary carcinoma). Activating mutations of the TShR gene were found in 12 of 15 hyperfunctioning follicular thyroid adenomas. In one hyperfunctioning adenoma, which was negative for TShR mutations, a mutation in codon 227 of the Gs alpha gene was identified. At variance with hyperfunctioning thyroid adenomas, no mutation of the TShR or Gs alpha genes was detected in nonfunctioning thyroid nodules. In conclusion, our findings clearly define a different molecular pathogenetic mechanism in hyperfunctioning and nonfunctioning follicular thyroid adenomas. Activation of the cAMP cascade, which leads to proliferation but maintains differentiation of follicular thyroid cells, typically occurs in hyperfunctioning thyroid adenomas. Oncogenes other than the TShR and Gs alpha genes are probably involved in nonfunctioning follicular adenomas.

Cabozantinib-induced thyroid dysfunction: a review of two ongoing trials for metastatic bladder cancer and sarcoma.

PubMed

Yavuz, Sahzene; Apolo, Andrea B; Kummar, Shivaani; del Rivero, Jaydira; Madan, Ravi A; Shawker, Thomas; Reynolds, James; Celi, Francesco S

2014-08-01

Thyroid dysfunction is a common adverse event associated with tyrosine kinase inhibitors (TKI), but its underlying pathophysiology is unclear. Cabozantinib is a novel TKI currently Food and Drug Administration approved for advanced medullary thyroid cancer and tested in clinical trials on solid tumors including prostate, liver, bladder, breast, and ovarian cancer. We analyzed the thyroid function of patients enrolled in two phase 2 clinical trials using cabozantinib at the National Institutes of Health Clinical Center. Two cases of thyroiditis associated with cabozantinib therapy are presented in detail, and a systematic review of the literature on TKI-associated thyroid dysfunction is also discussed. Between September 2012 and September 2013, 33 patients were treated with cabozantinib, and follow-up thyroid function tests were available for 31 (20 males, 11 females; age 59±1 years). Thyroid dysfunction was recorded in the majority of patients (93.1%), with a predominance of subclinical hypothyroidism. Two cases showed a biphasic pattern of thyroid dysfunction characterized by a transient thyrotoxicosis followed by hypothyroidism. Color Doppler demonstrated an increase in vascularization during the thyrotoxic phase, but no uptake was visualized on nuclear medicine imaging. A systematic review of the literature resulted in the identification of 40 original manuscripts, of which 13 were case series and 6 were case reports describing TKI-associated thyroid dysfunction. TKI therapy often results in clinically significant thyroid dysfunction. Cabozantinib treatment commonly results in thyroid dysfunction varying from subclinical hypothyroidism to symptomatic thyrotoxicosis. Early detection and characterization of cabozantinib-associated thyroid dysfunction and close follow-up are essential to provide adequate management of this common adverse event.

Cabozantinib-Induced Thyroid Dysfunction: A Review of Two Ongoing Trials for Metastatic Bladder Cancer and Sarcoma

PubMed Central

Yavuz, Sahzene; Apolo, Andrea B.; Kummar, Shivaani; del Rivero, Jaydira; Madan, Ravi A.; Shawker, Thomas; Reynolds, James

2014-01-01

Background: Thyroid dysfunction is a common adverse event associated with tyrosine kinase inhibitors (TKI), but its underlying pathophysiology is unclear. Cabozantinib is a novel TKI currently Food and Drug Administration approved for advanced medullary thyroid cancer and tested in clinical trials on solid tumors including prostate, liver, bladder, breast, and ovarian cancer. Methods: We analyzed the thyroid function of patients enrolled in two phase 2 clinical trials using cabozantinib at the National Institutes of Health Clinical Center. Two cases of thyroiditis associated with cabozantinib therapy are presented in detail, and a systematic review of the literature on TKI-associated thyroid dysfunction is also discussed. Results: Between September 2012 and September 2013, 33 patients were treated with cabozantinib, and follow-up thyroid function tests were available for 31 (20 males, 11 females; age 59±1 years). Thyroid dysfunction was recorded in the majority of patients (93.1%), with a predominance of subclinical hypothyroidism. Two cases showed a biphasic pattern of thyroid dysfunction characterized by a transient thyrotoxicosis followed by hypothyroidism. Color Doppler demonstrated an increase in vascularization during the thyrotoxic phase, but no uptake was visualized on nuclear medicine imaging. A systematic review of the literature resulted in the identification of 40 original manuscripts, of which 13 were case series and 6 were case reports describing TKI-associated thyroid dysfunction. Conclusion: TKI therapy often results in clinically significant thyroid dysfunction. Cabozantinib treatment commonly results in thyroid dysfunction varying from subclinical hypothyroidism to symptomatic thyrotoxicosis. Early detection and characterization of cabozantinib-associated thyroid dysfunction and close follow-up are essential to provide adequate management of this common adverse event. PMID:24724719

Hyperthyroidism in an infant of a mother with autoimmune hypothyroidism with positive TSH receptor antibodies.

PubMed

Joshi, Kriti; Zacharin, Margaret

2018-04-25

Neonatal hyperthyroidism is rare, seen in infants of mothers with Graves' disease (GD), with transplacental transfer of thyroid-stimulating hormone receptor (TSHR) antibodies (TRAbs). We describe a neonate with severe hyperthyroidism due to TRAbs, born to a mother with autoimmune hypothyroidism. A baby boy born preterm at 35 weeks had irritability, tachycardia and proptosis after birth. The mother had autoimmune hypothyroidism, from age 10, with thyroxine replacement and normal thyroid function throughout her pregnancy. She had never been thyrotoxic. There was a family history of Hashimoto's thyroiditis (HT) and GD. The baby's thyroid function on day 3 demonstrated gross thyrotoxicosis, TSH<0.01 mIU/L (normal range [NR]<10 mIU/L), free thyroxine (FT4)>77 pmol/L (20-35), free triiodothyronine (FT3) 15.4 pmol/L (4.2-8.3) and TRAb 18.4 IU/L (<1.8). The mother's TRAb was 24.7 IU/L. Thyrotoxicosis required propranolol and carbimazole (CBZ). Thyroid function normalized within 10 days. The baby was weaned off medication by 7 weeks. He remains euthyroid. We postulate that this mother had co-existing destructive thyroiditis and thyroid-stimulating antibodies (TSAbs) and TSHR blocking antibodies (TBAb), rendering her unable to raise a thyrotoxic response to the TSAbs but with predominant TSAb transmission to her infant. Maternal history of any thyroid disorder may increase the risk of transmission to an infant, requiring a careful clinical assessment of the neonate, with important implications for future pregnancies.

Feline focus: Diagnostic testing for feline thyroid disease: hypothyroidism.

PubMed

Peterson, Mark E

2013-08-01

Although naturally occurring hypothyroidism is very rare in cats, iatrogenic hypothyroidism is a recognized complication of treatment for hyperthyroidism. However, confirming the diagnosis of hypothyroidism in cats is not generally straightforward. The potential for false-negative and false-positive results exists with all thyroid function tests, especially in older cats that may have concurrent nonthyroidal illness. Therefore, all thyroid function test results must be interpreted in light of the cat's history, clinical signs, and other laboratory findings. If a low to low-normal serum thyroxine (T4) value is found in a cat that has been treated for hyperthyroidism, repeating the total T4 analysis, determining free T4 and thyroid stimulating hormone (TSH) concentrations, or performing a TSH stimulation test or thyroid scintigraphy may be needed to confirm the diagnosis.

TPA induces a block of differentiation and increases the susceptibility to neoplastic transformation of a rat thyroid epithelial cell line.

PubMed

Portella, G; Vitagliano, D; Li, Z; Sferratore, F; Santoro, M; Vecchio, G; Fusco, A

1998-01-01

The PC Cl 3 cell line is a well-characterized epithelial cell line of rat thyroid origin. This cell line retains in vitro the typical markers of thyroid differentiation: thyroglobulin (TG) synthesis and secretion, iodide uptake, thyroperoxidase (TPO) expression, and dependency on TSH for growth. Although the differentiated phenotype of thyroid cells has been relatively well described, the molecular mechanisms that regulate both differentiation and neoplastic transformation of thyroid cells still need to be investigated in detail. Protein kinase C (PKC), the target of tetradecanoylphorbol acetate (TPA), regulates growth and differentiation of several cell types. Here we show that treatment of PC Cl 3 cells with TPA induces an acute block of thyroid differentiation. TPA-treated PC Cl 3 cells are unable to trap iodide and the expression levels of thyroglobulin, TSH receptor, and TPO genes are drastically reduced by TPA treatment. This differentiation block is not caused by a reduced expression of one of the master genes of thyroid differentiation, the thyroid transcription factor 1 (TTF-1). TPA-treated PC Cl 3 cells display an increased growth rate indicating that, in addition to the differentiation block, TPA also significantly affects the growth regulation of thyroid cells. Finally, TPA treatment dramatically increases the number of transformation foci induced in PC Cl 3 cells by retroviruses carrying v-Ki-ras, v-Ha-ras, and v-mos oncogenes. These findings support the notion that the PKC pathway can influence proliferation, differentiation, and neoplastic transformation of thyroid cells in culture.

Multifocal hyperfunctioning thyroid carcinoma without metastases.

PubMed

Nishida, Akiko T; Hirano, Shigeru; Asato, Ryo; Tanaka, Shinzo; Kitani, Yoshiharu; Honda, Nobumitsu; Fujiki, Nobuya; Miyata, Kouji; Fukushima, Hideyuki; Ito, Juichi

2008-09-01

Hyperthyroidism due to thyroid carcinoma is rare, and most cases are caused by hyperfunctioning metastatic thyroid carcinoma rather than primary carcinoma. Among primary hyperfunctioning thyroid carcinoma, multifocal thyroid carcinoma is exceedingly rare, with the only one case being reported in the literature. Here, we describe the case of a 62-year-old woman with multifocal functioning thyroid carcinoma. Technetium-99m (99m Tc) scintigraphic imaging showed four hot areas in the thyroid gland. Histopathological examination of all four nodules revealed papillary carcinoma, corresponding to hot areas in the 99m Tc scintigram. DNA sequencing of the thyrotropin receptor (TSH-R) gene from all nodules revealed no mutation, indicating that activation of TSH-R was unlikely in the pathophysiogenesis of hyperfunctioning thyroid carcinoma in the present case.

When to consider thyroid dysfunction in the neurology clinic.

PubMed

Mistry, Niraj; Wass, John; Turner, Martin R

2009-06-01

There are many neurological manifestations of thyroid disease, and thyroid function has taken its place in the "routine bloods" of neurology practice. However, although conditions such as carpal tunnel syndrome prompt thyroid testing despite any clear evidence for this approach, other symptoms of potential significance in terms of thyroid disease may be overlooked in the busy general neurology clinic, or abnormal thyroid tests may be assumed to be incidental. Psychiatric disorders, loss of consciousness, movement disorders and weakness may all be manifestations of primary thyroid disease. This is a symptom-based review where we will consider the evidence (or lack of it) for the association of various neurological problems with thyroid dysfunction, and also the pitfalls in interpretation of the biochemical tests.

Potential protective effect of Pistacia lentiscus oil against chlorpyrifos-induced hormonal changes and oxidative damage in ovaries and thyroid of female rats.

PubMed

Chebab, Samira; Mekircha, Fatiha; Leghouchi, Essaid

2017-12-01

The purpose of this study was to evaluate the protective effect of Pistacia lentiscus oil (PLO), known for its antioxidant properties, on chlorpyrifos (CPF)-induced alterations in the thyroid, reproductive hormone levels, and oxidative damage in the ovaries and thyroid of adult Wistar rats. The animals were treated with orally administered PLO (2 mL/kg), CPF (6.75 mg/kg), and a combination of CPF and PLO for 30 days. Serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (Pg), estradiol (E 2 ), triiodothyronine (T3), thyroxine (T4), and thyroid-stimulating hormone (TSH) were assessed using chemiluminescence assay. Malondialdehyde (MDA), protein carbonyl (PC), and reduced glutathione (GSH) levels were examined in the ovaries and thyroid glands. The oil principal volatile compounds detected by gas chromatography analysis were: myrcene, α-pinene and limonene (26.21, 22.66 and 10.33%, respectively). No significant differences were observed between serum concentrations of TSH and FSH in the examined experimental groups. However, serum concentrations of LH, E 2 , Pg, T3, and T4 decreased significantly in CPF-treated rats in comparison with the controls. The body weight and relative weight of ovaries and thyroids in this group were also significantly reduced. The MDA and PC content increased significantly, while the GSH content was markedly depressed in the thyroid and ovaries of rats treated with CPF. Co-administration of PLO and CPF effectively ameliorated the adverse effects; the oxidative damage was reduced and the levels of thyroid and reproductive hormones restored to a normal range. In conclusion, it appears that PLO substantially alleviates the CPF-induced oxidative damage and hormonal alterations. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Thyroid function in mice with compound heterozygous and homozygous disruptions of SRC-1 and TIF-2 coactivators: evidence for haploinsufficiency.

PubMed

Weiss, Roy E; Gehin, Martine; Xu, Jianming; Sadow, Peter M; O'Malley, Bert W; Chambon, Pierre; Refetoff, Samuel

2002-04-01

Steroid receptor coactivator (SRC)-1 and transcriptional intermediary factor (TIF)-2 are homologous nuclear receptor coactivators. We have investigated their possible redundancy as thyroid hormone (TH) coactivators by measuring thyroid function in compound SRC-1 and TIF-2 knock out (KO) mice. Whereas SRC-1 KO (SRC-1(-/-)) mice are resistant to TH and SRC-1(+/-) are not, we now demonstrate that TIF-2 KO (TIF-2(-/-)) mice have normal thyroid function. Yet double heterozygous, SRC-1(+/-)/TIF-2(+/-) mice manifested resistance to TH of a similar degree as that in mice completely deficient in SRC-1. KO of both SRC-1 and TIF-2 resulted in marked increases of serum TH and thyrotropin concentrations. This work demonstrates gene dosage effect in nuclear coactivators manifesting as haploinsufficiency and functional redundancy of SRC-1 and TIF-2.

Effects of hyperthyroidism on hand grip strength and function.

PubMed

Erkol İnal, Esra; Çarlı, Alparslan Bayram; Çanak, Sultan; Aksu, Oğuzhan; Köroğlu, Banu Kale; Savaş, Serpil

2015-01-01

Hyperthyroidism is a pathologic condition in which the body is exposed to excessive amounts of circulating thyroid hormones. Skeletal muscle is one of the major target organs of thyroid hormones. We evaluated hand grip strength and function in patients with overt hyperthyroidism. Fifty-one patients newly diagnosed with hyperthyroidism and 44 healthy controls participated in this study. Age, height, weight, and dominant hand of all participants were recorded. The diagnosis of hyperthyroidism was confirmed by clinical examination and laboratory tests. Hand grip strength was tested at the dominant hand with a Jamar hand dynamometer. The grooved pegboard test (PGT) was used to evaluate hand dexterity. The Duruöz Hand Index (DHI) was used to assess hand function. No significant differences were found in terms of clinical and demographic findings between the patients with hyperthyroidism and healthy controls (p > 0.05). Significant differences were found between the patients with hyperthyroidism and healthy controls regarding PGT and DHI scores (p < 0.05). Hyperthyroidism seemed to affect hand dexterity and function more than hand grip strength and seemed to be associated with reduced physical function more than muscle strength. This may also indicate that patients with hyperthyroidism should be evaluated by multidisplinary modalities.

Effects of postnatal administration of diethylstilbestrol on puberty and thyroid function in male rats.

PubMed

Shin, Jae-Ho; Kim, Tae Sung; Kang, Il Hyun; Kang, Tae Seok; Moon, Hyun Ju; Han, Soon-Young

2009-10-01

To examine the effects of diethylstilbestrol (DES) on male pubertal development and thyroid function, juvenile male Sprague-Dawley rats were given DES daily by oral intubation at doses of 10, 20 and 40 microg/kg/day from postnatal day 33 for 20 days. Prepuce separation was significantly delayed at the dose of 20 microg/kg/day and above in the DES-treated rats. DES treatment induced a significant reduction in the weights of testes, epididymides, the ventral prostate, seminal vesicles plus coagulating glands and fluid, levator ani bulbocavernosus muscles, Cowper's glands and the glans penis. The weights of the liver and adrenals increased in the DES-treated animals. DES caused a dose-dependent reduction in germ cells; in particular the spermatids were mainly affected. The serum levels of testosterone and luteinizing hormone were significantly reduced in the DES-treated groups, but that of estradiol decreased. No differences were observed in the serum thyroxine levels of the control and DES-treated groups. In microscopic observation of the DES-treated animals, degeneration of germ cells and tubular atrophy in the testis were noted, but there were no microscopic changes in the thyroid. These results indicate that DES affected the pubertal development of juvenile male rats and that its mode of action may be related to alterations in hormone levels.

Paraneoplastic hypercalcemia in a dog with thyroid carcinoma

PubMed Central

Lane, Amy E.; Wyatt, Kenneth M.

2012-01-01

This case report describes a dog with thyroid carcinoma and paraneoplastic hypercalcemia. Following thyroidectomy the dog became hypocalcemic and required supplementation with calcitriol and calcium carbonate. During the following 2 years, attempts to reduce the supplementation resulted in hypocalcemia. The dog died from renal failure with no evidence of thyroid carcinoma. PMID:23543930

The Effect of Electromagnetic Radiation due to Mobile Phone Use on Thyroid Function in Medical Students Studying in a Medical College in South India.

PubMed

Baby, Nikita Mary; Koshy, George; Mathew, Anna

2017-01-01

Enormous increase in mobile phone use throughout the world raises widespread concerns about its possible detrimental effect on human health. Radiofrequency waves are emitted by cell phones. They are non-ionising and the effect on the thyroid gland is part of their non thermal effects. The thyroid gland may be particularly vulnerable to this effect because of its normal anatomical position. The study was done to explore the association between radiation exposure and thyroid dysfunction among mobile phone users. It had an exploratory design and unit survey method to collect information from all medical students in a medical college in South India. Inclusion criteria included active use of mobile phone prior to and during the study period. Criteria for exclusion was presence of pre-existsting thyroid disease,thyroid nodule,thyroid goitre/nodule and altered thyroid function. The sample size was 83 undergraduate students. 71% of respondents had no family history of thyroid illness. Among the remainder,20.5% had a first degree relative with thyroid dysfunction,8.4% had a second degree relative affected. Clinical examination revealed that 79.5% of the respondents were normal,13.6% had thyroid swelling,3.6% had symptoms of thyroid dysfunction and 3.6% had both thyroid swelling and symptoms of thyroid dysfunction. 53% of the respondents spent 0.5 hrs on an average talking on the phone daily,28.9% spent 1.5 hrs daily and 10.8% of respondents spent over 3.5 hours. We found there was a significant correlation between total radiation exposure and an increase in TSH among both groups -in those with and without family history of thyroid illness. In our study there was a significant correlation between total radiation exposure and increasing TSH values among both all respondents.

Functional insulin receptors are overexpressed in thyroid tumors: is this an early event in thyroid tumorigenesis?

PubMed

Frittitta, L; Sciacca, L; Catalfamo, R; Ippolito, A; Gangemi, P; Pezzino, V; Filetti, S; Vigneri, R

1999-01-15

Insulin receptor (IR), a member of the receptor tyrosine kinase family, is expressed in normal thyroid cells and affects thyroid cell proliferation and differentiation. The authors measured IR content in benign and malignant thyroid tumors by three independent methods: a specific radioimmunoassay, 125I-insulin binding studies, and immunohistochemistry. The results obtained were compared with the IR content in paired, adjacent, normal thyroid tissue. To assess IR function in thyroid carcinoma cells, glucose uptake responsiveness to insulin was also studied in a human transformed thyroid cell line (B-CPAP) and in follicular carcinoma cells in primary culture. In 9 toxic adenomas, the average IR content was similar to that observed in the 9 paired normal thyroid tissue specimens from the same patients (2.2+/-0.3 vs. 2.1+/-0.3). In 13 benign nonfunctioning, or "cold," adenomas, the average IR content was significantly higher (P < 0.001) than in paired normal tissue specimens (4.3+/-0.5 vs. 1.8+/-0.1). In 12 papillary and 10 follicular carcinomas, IR content was significantly higher (P < 0.001) than in the adjacent normal thyroid tissue (4.0+/-0.4 vs. 1.6+/-0.2 and 5.6+/-1.0 vs. 1.8+/-0.2, respectively). The finding of a higher IR content in benign "cold" adenomas and in thyroid carcinomas was confirmed by both binding and immunostaining studies. The current studies indicate that 1) IR content is elevated in most follicular and papillary differentiated thyroid carcinomas, and 2) IR content is also elevated in most benign follicular adenomas ("cold" nodules) but not in highly differentiated, hyperfunctioning follicular adenomas ("hot" nodules), which very rarely become malignant. This observation suggests that increased IR expression is not restricted to the thyroid malignant phenotype but is already present in the premalignant "cold" adenomas. It may contribute, therefore, to thyroid tumorigenesis and/or represent an early event that gives a selective growth advantage to transformed thyroid cells.

Relationship between thyroid functions and urinary growth hormone secretion in patients with hyper- and hypothyroidism.

PubMed

Murao, K; Takahara, J; Sato, M; Tamaki, M; Niimi, M; Ishida, T

1994-10-01

Thyroid hormone plays an important role in growth hormone (GH) synthesis and secretion. To study the relationship between thyroid function and urinary GH secretion in the hyperthyroid and hypothyroid states, we measured thyroid hormones, simultaneously with serum and urinary GH levels, in 54 patients with thyroid diseases. GH-releasing hormone (GRH) test was performed in 18 patients in order to evaluate serum and urinary GH responses to GRH in hyper- and hypothyroid states. Serum thyroid hormone levels were strongly correlated with the urinary GH levels in the patients, and the correlation was greater than that between serum thyroid hormone and serum GH levels. Urinary GH levels were significantly higher in the hyperthyroid patients than in the euthyroid and hypothyroid patients, although serum GH levels were not significantly different among these three groups. Serum GH response to GRH was significantly decreased in hyperthyroid patients as compared to euthyroid patients. However, urinary GH levels after GRH administration were not decreased in the hyperthyroid patients. These results suggest that hyperthyroid states increase GH in urine and may accelerate the urinary clearance of GH.

Transient thyrotoxicosis from thyroiditis induced by sibutramine overdose: a case report.

PubMed

Kim, S K; Lee, S M; Yoo, S S; Hahm, J R; Jung, J H; Kim, H S; Kim, S; Chung, S I; Jung, T S

2013-08-01

Sibutramine is an antiobesity drug that inhibits the reuptake of serotonin and noradrenalin in the hypothalamus. A 37-year-old Korean man presented to the emergency room for the oral intake of 280 mg of sibutramine. The patient was in thyrotoxic state. The (99m)Technetium-pertechnetate thyroid scan showed irregular uptake of radioisotope and thyroid-stimulating hormone receptor antibody and thyroperoxidase antibody were negative. Thyroid function normalized after that. The patient had transient thyrotoxicosis with thyroiditis. We report a case of thyrotoxicosis accompanied by thyroiditis resulting from the intentional overdose of sibutramine.

Thyroid Function Changes Related to Use of Iodinated Water in United States Space Program

NASA Technical Reports Server (NTRS)

McMonigal, Kathleen A.; Braverman, Lewis E.; Dunn, John T.; Stanbury, John B.; Wear, Mary L.; Hamm, Peggy B.; Sauer, Richard L.; Billica, Roger D.; Pool, Sam L.

1999-01-01

The National Aeronautics and Space Administration (NASA) has used iodination as a method of microbial disinfection of potable water systems in United States spacecraft and long-duration habitability modules. A review of the effects on the thyroid following consumption o iodinated water by NASA astronauts was conducted. Pharmacological doses of iodine consumed by astronauts transiently decreased thyroid function, as reflected in serum TSH values. Although the adverse effects of excess iodine consumption in susceptible individuals are well documented, exposure to high doses of iodine during space flight did not result in a statistically significant increase in long-term thyroid disease in the astronaut population.

Methyltestosterone-induced transient hyperthyroidism in a hypothyroid patient.

PubMed

Krysiak, R; Okopien, B

2013-01-01

In this paper we report different effects of methyltestosterone administration on thyroid function in two twin brothers, one of whom suffered from hypothyroidism, while the other was apparently healthy. Methyltestosterone, which is a non-aromatisable androgen, resulted in a marked reduction of thyroxine-binding globulin (TBG), irrespectively of the patient's hormonal status, while the impact on free thyroid hormones depended on baseline thyroid function. Our research shows that a possibility of the use of non-aromatisable androgens or other drugs affecting TBG levels should be taken into consideration in all hypothyroid patients receiving levothyroxine, in whom thyroid hormone status suddenly changes without any apparent reason.

FUNCTIONAL CHANGES IN THE THYROID AS A GENERAL IRRADIATION REACTION FOLLOWING TREATMENT OF PATIENTS WITH CANCER OF THE CERVIX

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pisareva, N.A.

1963-01-01

Study of the functional state of the thyroid gland by means of I/sup 131/ demonstrated a distinct percentage increase of the accumulation of this isotope at the peak of the general radiation reaction in 39 out of 67 patients with cancer of the cervix who were subjected to curie roentgen therapy. In 28 patients, in whom menopause had developed, several years prior to discovery of the cervical cancer and application of irradiation therapy, the function of the thyroid gland was not changed in comparison with the average functional indexes of healthy women of the corresponding age. (auth)

Association of maternal thyroid function during early pregnancy with offspring IQ and brain morphology in childhood: a population-based prospective cohort study.

PubMed

Korevaar, Tim I M; Muetzel, Ryan; Medici, Marco; Chaker, Layal; Jaddoe, Vincent W V; de Rijke, Yolanda B; Steegers, Eric A P; Visser, Theo J; White, Tonya; Tiemeier, Henning; Peeters, Robin P

2016-01-01

Thyroid hormone is involved in the regulation of early brain development. Since the fetal thyroid gland is not fully functional until week 18-20 of pregnancy, neuronal migration and other crucial early stages of intrauterine brain development largely depend on the supply of maternal thyroid hormone. Current clinical practice mostly focuses on preventing the negative consequences of low thyroid hormone concentrations, but data from animal studies have shown that both low and high concentrations of thyroid hormone have negative effects on offspring brain development. We aimed to investigate the association of maternal thyroid function with child intelligence quotient (IQ) and brain morphology. In this population-based prospective cohort study, embedded within the Generation R Study (Rotterdam, Netherlands), we investigated the association of maternal thyroid function with child IQ (assessed by non-verbal intelligence tests) and brain morphology (assessed on brain MRI scans). Eligible women were those living in the study area at their delivery date, which had to be between April 1, 2002, and Jan 1, 2006. For this study, women with available serum samples who presented in early pregnancy (<18 weeks) were included. Data for maternal thyroid-stimulating hormone, free thyroxine, thyroid peroxidase antibodies (at weeks 9-18 of pregnancy), and child IQ (assessed at a median of 6·0 years of age [95% range 5·6-7·9 years]) or brain MRI scans (done at a median of 8·0 years of age [6·2-10·0]) were obtained. Analyses were adjusted for potential confounders including concentrations of human chorionic gonadotropin and child thyroid-stimulating hormone and free thyroxine. Data for child IQ were available for 3839 mother-child pairs, and MRI scans were available from 646 children. Maternal free thyroxine concentrations showed an inverted U-shaped association with child IQ (p=0·0044), child grey matter volume (p=0·0062), and cortex volume (p=0·0011). For both low and high maternal free thyroxine concentrations, this association corresponded to a 1·4-3·8 points reduction in mean child IQ. Maternal thyroid-stimulating hormone was not associated with child IQ or brain morphology. All associations remained similar after the exclusion of women with overt hypothyroidism and overt hyperthyroidism, and after adjustment for concentrations of human chorionic gonadotropin, child thyroid-stimulating hormone and free thyroxine or thyroid peroxidase antibodies (continuous or positivity). Both low and high maternal free thyroxine concentrations during pregnancy were associated with lower child IQ and lower grey matter and cortex volume. The association between high maternal free thyroxine and low child IQ suggests that levothyroxine therapy during pregnancy, which is often initiated in women with subclinical hypothyroidism during pregnancy, might carry the potential risk of adverse child neurodevelopment outcomes when the aim of treatment is to achieve high-normal thyroid function test results. The Netherlands Organisation for Health Research and Development (ZonMw) and the European Community's Seventh Framework Programme. Copyright © 2016 Elsevier Ltd. All rights reserved.

Multifactorial determinants of cognition — Thyroid function is not the only one

PubMed Central

Moncayo, Roy; Ortner, Karina

2015-01-01

Background Since the 1960s hypothyroidism together with iodine deficiency have been considered to be a principal determinant of cognition development. Following iodine supplementation programs and improved treatment options for hypothyroidism this relation might not be valid in 2015. On the other hand neurosciences have added different inputs also related to cognition. Scope of review We will examine the characteristics of the original and current publications on thyroid function and cognition and also add some general determinants of intelligence and cognition. One central issue for us is the relation of stress to cognition knowing that both physical and psychological stress, are frequent elements in subjects with thyroid dysfunction. We have considered a special type of stress called pre-natal stress which can influence cognitive functions. Fear and anxiety can be intermingled requiring mechanisms of fear extinction. Major conclusions Recent studies have failed to show an influence of thyroid medication during pregnancy on intellectual development. Neuroscience offers a better explanation of cognition than hypothyroidism and iodine deficiency. Additional factors relevant to cognition are nutrition, infection, prenatal stress, and early life stress. In turn stress is related to low magnesium levels. Magnesium supplementation can correct both latent hypothyroidism and acquired mild cognitive deficits. General significance Cognition is a complex process that depends on many determinants and not only on thyroid function. Magnesium deficiency appears to be a basic mechanism for changes in thyroid function as well as of cognition. PMID:26672993

Triple ectopic thyroid: A rare entity

PubMed Central

Nilegaonkar, Sujit; Naik, Chetna; Sonar, Sameer; Hirawe, Deepti

2011-01-01

Ectopic thyroid tissue is an uncommon congenital aberration. It is extremely rare to have three ectopic foci at three different sites. The thyroid scan has been used successfully to diagnose ectopic thyroid tissue. We report a case of ectopic thyroid tissue at base of tongue, another at the level of hyoid and third one as aberrant tissue at suprahyoid location in a 16 year old female who presented with swelling in front of neck. This patient was clinically diagnosed as thyroglossal cyst and was being planned for surgery. Preoperative thyroid scan helped in establishing diagnosis of ectopic thyroid which was the only functioning thyroid tissue. Thus, it prevented unnecessary surgery. Therefore it is suggested that thyroid scan and USG/CT scan must be done as routine work up in neck swellings pre operatively to avoid unnecessary surgeries. PMID:23559716

Cystinyl and pyroglutamyl-beta-naphthylamide hydrolyzing activities are modified coordinately between hypothalamus, liver and plasma depending on the thyroid status of adult male rats.

PubMed

Segarra, A B; Prieto, I; Martinez-Canamero, M; Vargas, F; De Gasparo, M; Vanderheyden, P; Zorad, S; Ramirez-Sanchez, M

2018-04-01

The hypothalamus determinates metabolic processes in liver through endocrine and autonomic control. Hypothalamic neuropeptides, such as thyrotropin releasing hormone or vasopressin, have been involved in liver metabolism. The thyroid status influences metabolic processes including liver metabolism in modulating those hypothalamic peptides whose functional status is regulated in part by aminopeptidase activities. In order to obtain data for a possible coordinated interaction between hypothalamus, plasma and liver, of some aminopeptidase activities that may partially reflect the hydrolysis of those peptides, pyroglutamyl- (pGluAP) and cystinyl- (CysAP) beta-naphthylamide hydrolyzing activities were determined fluorimetrically, both in their soluble and membrane-bound forms, in eu- hypo- and hyperthyroid adult male rats. Hyperthyroidism and hypothyroidism were induced with daily subcutaneous injections of tetraiodothyronine (300 μg/kg/day) or with 0.03% methimazole in drinking water for 6 weeks. Results demonstrated significant changes depending on the type of enzyme and the thyroid status. The most striking changes were observed for CysAP in liver where it was reduced in hypothyroidism and increased in hyperthyroidism. Significant intra- and inter-tissue correlations were observed. While there were positive inter-tissue correlations between liver, plasma and hypothalamus in eu-and hypothyroid rats, a negative correlation between hypothalamus and liver was observed in hyperthyroidism. These results suggest the influence of thyroid hormones and an interactive role for these activities in the control of liver metabolism. The present data also suggest a role for CysAP and pGluAP activities in liver function linked to their activities in hypothalamus.

[Functional tear production indices in thyroid eye disease].

PubMed

Safonova, T N; Likhvantseva, V G; Gontiurova, O A; Rudenko, E I; Vygodin, V A

2013-01-01

Analysis of functional tear production indices in patients with Grave's disease and thyroid eye disease confirmed lacrimal gland involvement in inflammatory autoimmune process. Close direct correlation was found between tear production and main disease characteristics - severity and activity.

Effects of 3-nitro-l-tyrosine on thyroid function in the rat: an experimental model for the dehalogenase defect

PubMed Central

Green, William L.

1971-01-01

The effects on thyroid function of an inhibitor of tyrosine dehalogenase, 3-nitro-L-tyrosine (MNT) have been investigated in rats. In preliminary studies, marked inhibition of iodotyrosine deiodination was demonstrated in rats drinking 8 mM MNT. A series of experiments was then performed in which rats received Remington low iodine diet and 8 mM MNT as drinking fluid. This regimen had the following effects, compared to the effects of a low iodine diet alone: (a) a decrease in serum protein-bound iodine, elevation of serum thyrotropin level, goiter, and growth inhibition all prevented or reversed by iodine supplements: (b) on initiation of MNT, a 2- to 3-fold increase in the rate of release of radioiodine from the thyroid and concomitant urinary excretion of large amounts of organic iodine: and (c) after 2 wk of MNT, a greatly increased rate of thyroidal uptake and release of 131I, an increase in the ratio of monoiodotyrosine-131I to diiodotyrosine-131I in thyroid proteolysates and the appearance of labeled iodotyrosines in serum. Acute administration of MNT intraperitoneally to rats on either an iodine-deficient or iodine-sufficient diet did not inhibit thyroidal uptake of 131I or alter the distribution of 131I among thyroidal iodoamino acids. It is concluded that MNT is an effective inhibitor of iodotyrosine deiodination in vivo, without other important actions on thyroid function. Thus, MNT treatment affords a model for the human dehalogenase defect. By provoking iodotyrosine secretion and consequent urinary loss of iodine, MNT can exaggerate the effects of a low iodine intake, producing goitrous hypothyroidism despite a rapid rate of iodine turnover in the thyroid. Images PMID:5129302

Factors associated with serum thyroglobulin in a Ukrainian cohort exposed to iodine-131 from the accident at the Chernobyl Nuclear Plant.

PubMed

Peters, Kamau O; Tronko, Mykola; Hatch, Maureen; Oliynyk, Valeriy; Terekhova, Galyna; Pfeiffer, Ruth M; Shpak, Victor M; McConnell, Robert J; Drozdovitch, Vladimir; Little, Mark P; Zablotska, Lydia B; Mabuchi, Kiyohiko; Brenner, Alina V; Cahoon, Elizabeth K

2017-07-01

Serum thyroglobulin (Tg) is associated with the presence of thyroid disease and has been proposed as a biomarker of iodine status. Few studies have examined factors related to serum Tg in populations environmentally exposed to ionizing radiation and living in regions with endemic mild-to-moderate iodine deficiency. We screened 10,430 individuals who were living in Ukraine and under 18 years of age at the time of the 1986 Chernobyl Nuclear Power Plant accident for thyroid disease from 2001 to 2003. We estimated the percent change (PC) in serum Tg associated with demographic factors, iodine-131 thyroid dose, and indicators of thyroid structure and function using linear regression. We also examined these relationships for individuals with and without indications of thyroid abnormality. Mean and median serum Tg levels were higher among participants with abnormal thyroid structure/function. Percent change in serum Tg increased among females, smokers and with older age (p-values<0.001), and Tg increased with increasing thyroid volume, and serum thyrotropin (p-values for trend<0.001). We found no evidence of significant associations between iodine-131 thyroid dose and Tg. Serum Tg levels were inversely associated with iodized salt intake (PC=-7.90, 95% confidence interval: -12.08, -3.52), and over the range of urinary iodine concentration, the odds of having elevated serum Tg showed a U-shaped curve with elevated Tg at low and high urinary iodine concentrations. Serum Tg may be a useful indicator of population iodine status and a non-specific biomarker of structural and functional thyroid abnormalities in epidemiological studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Hypothyroidism after Hemithyroidectomy: The Incidence and Risk Factors.

PubMed

Chotigavanich, Chanticha; Sureepong, Paiboon; Ongard, Sunun; Eiamkulvorapong, Apaporn; Boonyaarunnate, Thiraphon; Chongkolwatana, Cheerasook; Metheetrairut, Choakchai

2016-01-01

To evaluate the incidence of post-hemithyroidectomy hypothyroidism and identify possible risk factors that indicates whether patients require thyroid function monitoring after surgery. A retrospective review of patients with benign non-toxic thyroid disease undergoing hemithyroidectomy between April 2004 and November 2008 in the Department of Otorhinolaryngology, Siriraj Hospital was conducted All patients were in euthyroid state preoperatively. Thyroid specimens were examined for pathological diagnosis and degree of lymphocytic infiltration in thyroid tissue, and thyroid function was evaluated again six weeks after surgery. One hundred patients who received hemithyroidectomy were recruited for the present study. All had normal preoperative thyroid function. Six weeks after surgery, 27% of the cases developed hypothyroidism (6% overt or symptomatic hypothyroidism and 21% subclinical hypothyroidism). The mean preoperative thyrotropin level was significantly higher in the hypothyroid group than in the euthyroid group (1.9±1.2 vs. 1.1±0.7 micro IU/ml). Fifty-eight point three percent of patients with preoperative thyroid stimulating hormone (TSH) level more than or equal 2 micro IU/ml developed hypothyroidism in comparison to only 17.1% of those with preoperative TSH <2 micro IU/ml (odds ratio 6.8). Fifteen patients had signifcant lymphocytic infiltration (grade 2-4); nine of those (60%) had post-operative hypothyroidism. In contrary, only 18 of 85 patients (21.2%) with minimal infiltrates (grade 0-1) developed hypothyroidism (odds ratio 5.6). Twenty-seven percent of the patients in the present study developed hypothyroidism after hemithyroidectomy. Preoperative TSH more than or equal 2 micro IU/ml and significant lymphocytic infiltration in thyroid tissue or thyroiditis warrant post-operative close TSH monitoring. The awareness of such risk factors for post-operative hypothyroidism would improve patients care.

The role of nerve monitoring to predict postoperative recurrent laryngeal nerve function in thyroid and parathyroid surgery.

PubMed

Eid, Issam; Miller, Frank R; Rowan, Stephanie; Otto, Randal A

2013-10-01

To determine the role and efficacy of intraoperative recurrent laryngeal nerve (RLN) stimulation in the prediction of early and permanent postoperative nerve function in thyroid and parathyroid surgery. A retrospective review of thyroid and parathyroid surgeries was performed with calculation of sensitivity and specificity of the response of intraoperative stimulation for different pathological groups. Normal electromyography (EMG) response with 0.5 mAmp stimulation was considered a positive stimulation response with postoperative function determined by laryngoscopy. No EMG response at >1-2 mAmps was considered a negative response. The rates of early and permanent paralysis, as well as sensitivity, specificity, and positive and negative predictive values for postoperative nerve function were calculated for separate pathological groups. The number of nerves at risk analyzed was 909. The overall early and permanent paralysis rates were 3.1% and 1.2%, respectively, with the highest rate being for Grave's disease cases. The overall sensitivity was 98.4%. The specificity was lower at 62.5% but acceptable in thyroid carcinoma and Grave's disease patients. The majority of nerves with a positive stimulation result and postoperative paralysis on laryngoscopy recovered function in 3 to 12 weeks, showing positive stimulation to be a good predictor of eventual recovery. Stimulation of the RLN during thyroid and parathyroid surgery is a useful tool in predicting postoperative RLN function. The sensitivity of stimulation is high, showing positive stimulation to be an excellent predictor of normal nerve function. Negative stimulation is more predictive of paralysis in cases of thyroid carcinoma and Grave's disease. 2b. Copyright © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Thyroid organotypic rat and human cultures used to investigate drug effects on thyroid function, hormone synthesis and release pathways.

PubMed

Vickers, Alison E M; Heale, Jason; Sinclair, John R; Morris, Stephen; Rowe, Josh M; Fisher, Robyn L

2012-04-01

Drug induced thyroid effects were evaluated in organotypic models utilizing either a rat thyroid lobe or human thyroid slices to compare rodent and human response. An inhibition of thyroid peroxidase (TPO) function led to a perturbation in the expression of key genes in thyroid hormone synthesis and release pathways. The clinically used thiourea drugs, methimazole (MMI) and 6-n-propyl-2-thioruacil (PTU), were used to evaluate thyroid drug response in these models. Inhibition of TPO occurred early as shown in rat thyroid lobes (2 h) and was sustained in both rat (24-48 h) and human (24 h) with ≥ 10 μM MMI. Thyroid from rats treated with single doses of MMI (30-1000 mg/kg) exhibited sustained TPO inhibition at 48 h. The MMI in vivo thyroid concentrations were comparable to the culture concentrations (~15-84 μM), thus demonstrating a close correlation between in vivo and ex vivo thyroid effects. A compensatory response to TPO inhibition was demonstrated in the rat thyroid lobe with significant up-regulation of genes involved in the pathway of thyroid hormone synthesis (Tpo, Dio1, Slc5a5, Tg, Tshr) and the megalin release pathway (Lrp2) by 24h with MMI (≥ 10 μM) and PTU (100 μM). Similarly, thyroid from the rat in vivo study exhibited an up-regulation of Dio1, Slc5a5, Lrp2, and Tshr. In human thyroid slices, there were few gene expression changes (Slc5a5, ~2-fold) and only at higher MMI concentrations (≥ 1500 μM, 24h). Extended exposure (48 h) resulted in up-regulation of Tpo, Dio1 and Lrp2, along with Slc5a5 and Tshr. In summary, TPO was inhibited by similar MMI concentrations in rat and human tissue, however an increased sensitivity to drug treatment in rat is indicated by the up-regulation of thyroid hormone synthesis and release gene pathways at concentrations found not to affect human tissue. Copyright © 2012 Elsevier Inc. All rights reserved.

Two novel mutations in the sixth transmembrane segment of the thyrotropin receptor gene causing hyperfunctioning thyroid nodules.

PubMed

Gozu, Hulya; Avsar, Melike; Bircan, Rifat; Claus, Maren; Sahin, Serap; Sezgin, Ozlem; Deyneli, Oguzhan; Paschke, Ralf; Cirakoglu, Beyazit; Akalin, Sema

2005-04-01

Autonomously functioning thyroid nodules (AFTNs) can present as hyperfunctioning adenomas or toxic multinodular goiters. In the last decade, a large number of activating mutations have been identified in the thyrotropin receptor (TSHR) gene in autonomously functioning thyroid nodules. Most have been situated close to, or within the sixth transmembrane segment and third intracellular loop of the TSHR where the receptor interacts with the Gs protein. In this study we describe two novel mutations in the sixth transmembrane segment of the TSHR causing hyperfunctioning thyroid nodules. Genomic DNAs were isolated from four hyperfunctioning thyroid nodules, normal tissues and peripheral leukocytes of two patients with toxic multinodular goiter. After amplifying the related regions, TSHR and G(s)alpha genes were analyzed by single-strand conformation polymorphism (SSCP) analysis. The precise localization of the mutations was identified by automatic DNA sequence analysis. Functional studies were done by site-directed mutagenesis and transfection of a mutant construct into COS-7 cells. We identified two novel TSHR mutations in two hyperfunctioning thyroid nodules: Phe631Val in the first patient and Iso630Met in the second patient. Both mutant receptors display an increase in constitutive stimulation of basal cyclic adenosine monophosphate (cAMP) levels compared to the wild-type receptor. This confirms that these mutant receptors cause hyperfunctioning thyroid nodules.

Burning mouth syndrome (BMS): evaluation of thyroid and taste.

PubMed

Femiano, F; Gombos, F; Esposito, V; Nunziata, M; Scully, Crispian

2006-01-01

Burning mouth syndrome (BMS) is a chronic, intraoral burning sensation seen mainly in middle-aged and post-menopausal females, without identifiable oral lesions or abnormal laboratory findings, but often associated with psychogenic disorders such as depression. The latter can have a range of causes, including hormonal. Since there may be connections between BMS, psychogenic changes, hormonal changes and taste abnormalities, we have examined aspects of taste and thyroid function. We selected 50 patients with BMS (study group) and 50 healthy subjects (control group) and analysed their ability to taste bitter, acid and spicy substances and analysed their thyroid function and Undertook thyroid echography. Taste sensation was normal in all controls. However, 30 of the patients with BMS reported ageusia for bitter taste and 2 had ageusia for acid. The use of pepper sauce (Tabasco) (spicy substance) produced a strong burning to the tongue in 28 patients of the BMS group but only in 10 controls. No control patients showed abnormality of thyroid function or echograpic abnormality. Five patients in the BMS group had biochemical evidence of hypothyroidism, 4 patients had raised levels of thyroid auto-antibodies and, of the 41 remaining BMS patients, most (34) had thyroid echographic changes indicative of nodularity. Hypothyroidism may be responsible for a negative influence on taste and consequent increase in trigeminal sensorial sensation (tactile, thermal and painful sensation).

Gender and Age Impacts on the Association Between Thyroid Function and Metabolic Syndrome in Chinese

PubMed Central

Meng, Zhaowei; Liu, Ming; Zhang, Qing; Liu, Li; Song, Kun; Tan, Jian; Jia, Qiang; Zhang, Guizhi; Wang, Renfei; He, Yajing; Ren, Xiaojun; Zhu, Mei; He, Qing; Wang, Shen; Li, Xue; Hu, Tianpeng; Liu, Na; Upadhyaya, Arun; Zhou, Pingping; Zhang, Jianping

2015-01-01

Abstract The relationship between thyroid dysfunction and metabolic syndrome (MS) is complex. We aimed to explore the impact of gender and age on their association in a large Chinese cohort. This cross-sectional study enrolled 13,855 participants (8532 male, 5323 female), who self-reported as healthy without any known previous diseases. Clinical data including anthropometric measurements, thyroid function, and serum metabolic parameters were collected. The associations between thyroid function and MS of both genders were analyzed separately after dividing thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and age into subgroups. MS risks were calculated by binary logistic regression models. Young males had significantly higher MS prevalence than females, yet after menopause, females had higher prevalence than males. Females had higher incidence of thyroid dysfunction than males. By using TSH quartiles as the categorical variables and the lowest quartile as reference, significantly increased MS risk was demonstrated in quartile 4 for males, yet quartiles 3 and 4 for females. By using FT3 quartiles as the categorical variables, significantly increased MS risk was demonstrated in quartile 2 to 4 for females only. By using age subgroups as the categorical variables, significantly increased MS risk was shown in both genders, with females (4.408–58.455) higher than males (2.588–4.943). Gender and age had substantial influence on thyroid function and MS. Females with high TSH and high FT3 had higher MS risks than males. Aging was a risk for MS, especially for females. Urgent need is necessary to initiate interventional programs. PMID:26683929

The effect of diltiazem on the manifestations of hyperthyroidism and thyroid function tests.

PubMed

Keleştimur, F; Aksu, A

1996-01-01

The aim of this study is to evaluate the effect of diltiazem on the symptoms and signs of hyperthyroidism and thyroid function tests and to assess whether diltiazem can be used associated with an anti-thyroid drug, propylthiouracil. Twenty-two patients with hyperthyroidism were included in a prospective, randomized and placebo controlled study. Group 1 (n:12) patients received diltiazem, 60 mg twice a day, for 30 days. Group 2 (n:10) patients received placebo for 30 days. The patients in both groups were given propylthiouracil, 100 mg three times a day, for the last 20 days of the study period. The patients remained in the hospital during the first 10 days. A standardized hyperthyroid symptom score (HSS) and thyroid function tests including thyroid-stimulating hormone (TSH), free thyroxine (free T4), free triiodothyronine (free T3), total thyroxine (T4) and total triiodothyronine (T3) were evaluated before and after 10 and 30 days of the study period. HSS decreased from 27.80 +/- 4.54 to 22.51 +/- 4.04 after 10 days of diltiazem therapy in Group 1 (p < 0.01). But there was no change in HSS in Group 2 (p > 0.01). No significant changes in thyroid function tests have occurred in both groups after 10 days of treatment. Diltiazem can be used in patients with hyperthyroidism to alleviate adrenergic manifestations. It can also be safely combined with propylthiouracil.

Recent developments in the investigation of thyroid regulation and thyroid carcinogenesis.

PubMed Central

Hard, G C

1998-01-01

This review covers new mechanistic information spanning the past 10 years relevant to normal and abnormal thyroid growth and function that may assist in the risk assessment of chemicals inducing thyroid follicular cell neoplasia. Recent studies have shown that thyroid regulation occurs via a complex interactive network mediated through several different messenger systems. Increased thyroid-stimulating hormone (TSH) levels activate the signal transduction pathways to stimulate growth and differentiation of the follicular cell. The important role of TSH in growth as well as in function helps to explain how disruptions in the thyroid-pituitary axis may influence thyroid neoplasia in rodents. New investigations that couple mechanistic studies with information from animal cancer bioassays (e. g., sulfamethazine studies) confirm the linkage between prolonged disruption of the thyroid-pituitary axis and thyroid neoplasia. New initiation/promotion studies in rodents also support the concept that chronic stimulation of the thyroid induced by goitrogens can result in thyroid tumors. Some of these studies confirm previous suggestions regarding the importance of chemically induced thyroid peroxidase inhibition and the inhibition of 3,3',5, 5'-tetraiodothyronine (T4, thyroxine) deiodinases on disruption of the thyroid-pituitary axis leading to thyroid neoplasia. Some comparative physiologic and mechanistic data highlight certain differences between rodents and humans that could be expected to confer an increased vulnerability of rodents to chronic hypersecretion of TSH. New data from epidemiologic and molecular genetic studies in humans contribute further to an understanding of thyroid neoplasia. Acute exposure to ionizing radiation, especially in childhood, remains the only verified cause of thyroid carcinogenesis in humans. Iodine deficiency studies as a whole remain inconclusive, even though several new studies in humans examine the role of dietary iodine deficiency in thyroid cancer. Specific alterations in gene expression have been identified in human thyroid neoplasia, linked to tumor phenotype, and thus oncogene activation and tumor-suppressor gene inactivation may also be factors in the development and progression of thyroid cancer in humans. An analysis by the U.S. EPA Risk Assessment Forum, prepared as a draft report in 1988 and completed in 1997, focused on the use of a threshold for risk assessment of thyroid follicular tumors. New studies, involving several chemicals, provide further support that there will be no antithyroid activity until critical intracellular concentrations are reached. Thus, for chemically induced thyroid neoplasia linked to disruptions in the thyroid-pituitary axis, a practical threshold for thyroid cancer would be expected. More information on thyroid autoregulation, the role of oncogene mutations and growth factors, and studies directly linking persistently high TSH levels with the sequential cellular development of thyroid follicular cell neoplasia would provide further confirmation. PMID:9681969

Functional hypothalamic amenorrhea: hypoleptinemia and disordered eating.

PubMed

Warren, M P; Voussoughian, F; Geer, E B; Hyle, E P; Adberg, C L; Ramos, R H

1999-03-01

Because the exact etiology of functional, or idiopathic, hypothalamic amenorrhea (FHA) is still unknown, FHA remains a diagnosis of exclusion. The disorder may be stress induced. However, mounting evidence points to a metabolic/nutritional insult that may be the primary causal factor. We explored the thyroid, hormonal, dietary, behavior, and leptin changes that occur in FHA, as they provide a clue to the etiology of this disorder. Fourteen cycling control and amenorrheic nonathletic subjects were matched for age, weight, and height. The amenorrheic subjects denied eating disorders; only after further, detailed questioning did we uncover a higher incidence of anorexia and bulimia in this group. The amenorrheic subjects demonstrated scores of abnormal eating twice those found in normal subjects (P < 0.05), particularly bulimic type behavior (P < 0.01). They also expended more calories in aerobic activity per day and had higher fiber intakes (P < 0.05); lower body fat percentage (P < 0.05); and reduced levels of free T4 (P < 0.05), free T3 (P < 0.05), and total T4 (P < 0.05), without a significant change in rT3 or TSH. Cortisol averaged higher in the amenorrheics, but not significantly, whereas leptin values were significantly lower (P < 0.05). Bone mineral density was significantly lower in the wrist (P < 0.05), with a trend to lower BMD in the spine (P < 0.08). Scores of emotional distress and depression did not differ between groups. The alterations in eating patterns, leptin levels, and thyroid function present in subjects with FHA suggest altered nutritional status and the suppression of the hypothalamic-pituitary-thyroid axis or the alteration of feedback set-points in women with FHA. Both lower leptin and thyroid levels parallel changes seen with caloric restriction. Nutritional issues, particularly dysfunctional eating patterns and changes in thyroid metabolism, and/or leptin effects may also have a role in the metabolic signals suppressing GnRH secretion and the pathogenesis of osteopenia despite normal body weight. These findings suggest that the mechanism of amenorrhea and low leptin in these women results mainly from a metabolic/nutritional insult.

TSH increment and the risk of incident type 2 diabetes mellitus in euthyroid subjects.

PubMed

Jun, Ji Eun; Jin, Sang-Man; Jee, Jae Hwan; Bae, Ji Cheol; Hur, Kyu Yeon; Lee, Moon-Kyu; Kim, Sun Wook; Kim, Jae Hyeon

2017-03-01

Thyroid function is known to influence glucose metabolism, and thyroid-stimulating hormone is the most useful parameter in screening for thyroid dysfunction. Therefore, the aim of this study was to investigate the incidence of type 2 diabetes according to baseline thyroid-stimulating hormone level and thyroid-stimulating hormone change in euthyroid subjects. We identified and enrolled 17,061 euthyroid subjects without diabetes among participants who had undergone consecutive thyroid function tests between 2006 and 2012 as a part of yearly health check-up program. Thyroid-stimulating hormone changes were determined by subtracting baseline thyroid-stimulating hormone level from thyroid-stimulating hormone level at 1 year before diagnosis of diabetes or at the end of follow-up in subjects who did not develope diabetes. During 84,595 person-years of follow-up, there were 956 new cases of type 2 diabetes. Cox proportional hazards models showed the risk of incident type 2 diabetes was significantly increased with each 1 μIU/mL increment in TSH after adjustment for multiple confounding factors (hazard ratio = 1.13, 95% confidence interval: 1.07-1.20, P < 0.001). Compared with individuals in the lowest tertile (-4.08 to 0.34 μIU/mL), those in the highest thyroid-stimulating hormone change tertile (0.41-10.84 μIU/mL) were at greater risk for incident type 2 diabetes (hazard ratio = 1.25, 95% confidence interval: 1.05-1.48, P for trend = 0.011). However, baseline thyroid-stimulating hormone level and tertile were not associated with the risk for diabetes. Prominent increase in thyroid-stimulating hormone concentration can be an additional risk factor for the development of type 2 diabetes in euthyroid subjects.

Thyroid hormone status and pituitary function in adult rats given oral doses of perfluorooctanesulfonate (PFOS)

EPA Science Inventory

Perfluorooctanesulfonate (PFOS) is widely distributed and persistent in humans and wildlife. Prior toxicological studies have reported decreased total and free thyroid hormones in serum without a major compensatory rise in thyrotropin (TSH) or altered thyroid gland histology. Alt...

DEVELOPMENT OF AN AMPHIBIAN METAMORPHOSIS MODEL FOR DETECTING THYROID AXIS DISRUPTION

EPA Science Inventory

Metamorphosis in Xenopus laevis represents an elaborate process of post-embryonic development which is thyroid hormone (TH) dependent. The development of a functional thyroid axis and the responses of tissues to different TH concentrations are well defined in this species, provid...

Cutaneous consequences of accelerated thyroid function.

PubMed

Mullin, G E; Eastern, J S

1986-02-01

General and specific cutaneous findings associated with hyperthyroidism are reviewed. Familiarity with these findings may aid the practitioner in the early diagnosis of thyroid diseases. Several normally idiopathic cutaneous diseases can occasionally be controlled if underlying thyroid disease is considered as a cause, and appropriate testing performed.

Long-term follow-up in toxic solitary autonomous thyroid nodules treated with radioactive iodine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huysmans, D.A.; Corstens, F.H.; Kloppenborg, P.W.

1991-01-01

The long-term effects of radioiodine treatment on thyroid function in patients with a toxic solitary autonomous thyroid nodule were evaluated. Fifty-two patients received a therapeutic dose of 20 mCi of iodine-131 ({sup 131}I). Duration of follow-up was 10 +/- 4 yr. Follow-up data included a biochemical evaluation of thyroid function. The failure rate (recurrent hyperthyroidism) was 2%. The incidence of hypothyroidism was 6% and was not related to the dose per gram of nodular tissue. Oral administration of 20 mCi of radioiodine is a simple and highly effective method for the treatment of patients with a toxic autonomous thyroid nodule.more » The risk of development of hypothyroidism is low if extranodular uptake of {sup 131}I is prevented. This can be achieved by not treating euthyroid patients, by no longer using injections of exogenous thyroid stimulating hormone in the diagnostic work-up of the patients and by always performing radioiodine imaging shortly before treatment.« less

Irradiation doses on thyroid gland during the postoperative irradiation for breast cancer.

PubMed

Akın, Mustafa; Ergen, Arzu; Unal, Aysegul; Bese, Nuran

2014-01-01

Thyroid gland is one of the radiosensitive endocrine organs in the body. It has been shown that direct irradiation of thyroid with total doses of 26 to 30 Gy can lead to functional abnormalities. In this study, irradiation doses on thyroid gland of the patients who received postoperative chest-wall/breast and regional nodal irradiation were assessed. Retrospective analyses of treatment plans from 122 breast cancer patients who were treated with 3D conformal radiotherapy (3D CRT) planning was performed. All patients received irradiation to supraclavicular/level III lymph nodes in addition to chest-wall/breast. A total dose of 46 Gy was delivered in 25 days to supraclavicular/level III lymph node region while a total dose of 50 Gy was delivered to whole breast/chest-wall. Thyroid gland was contoured on 2-5 mm thickness of computed tomography scans. Absolute thyroid volume, mean thyroid doses were calculated. The mean thyroid volume of all patients was 16.7 cc (min: 1.9 cc, max: 41.6 cc). The mean irradiation dose on was 22.5 Gy (0.32 Gy-46.5 Gy). The level of dose was higher than 26 Gy in 44% of the patients. In majority of the node-positive breast cancer patients treated with 3D CRT, the thyroid gland was exposed to considerable doses. On the other hand, for 44% of the patients are at risk for developing thyroid function abnormalities which should be considered during the routine follow-up.

Interrelationships between the thyroid gland and adrenal cortex during fear, cold and restraint in the sheep.

PubMed

Falconer, I R

1976-03-01

To examine the relationship between the functioning of the adrenal and thyroid glands in sheep, plasma cortisol concentration, concentration of protein-bound 125I from thyroid vein plasma, heart rate and blood pressure were measured in ewes bearing exteriorized thyroid glands. During these measurements stresses were imposed on the animals: fear induced by pistol shots or by a barking dog, cold by cooling and wetting, and physical restraint by a loose harness. Increases in plasma cortisol concentration of 2-6 mug/100 ml were observed with each type of stressor, the response rapidly decreasing with habituation of the animal. Increases in the concentration of protein-bound 125I from thyroid vein plasma were also observed repeatedly during cooling and wetting, occasionally after the introduction of a barking dog, and during continued restraint. Cooling and wetting was the only stress causing consistent parallel activation of the adrenal cortex and thyroid gland; the other stressors resulted in independent fluctuations of secretions, as indicated by plasma cortisol concentration and concentration of protein-bound 125I from thyroid vein plasma. No reciprocal relationship between thyroid gland and adrenal cortex activity was detected. It was concluded taht these ewes, which had been accustomed to normal experimental procedures for a period of 2 years, demonstrated functional independence of thyroid and adrenal cortical secretions when subjected to stress.

Loss of p53 Promotes Anaplasia and Local Invasion in ret/PTC1-Induced Thyroid Carcinomas

PubMed Central

La Perle, Krista M. D.; Jhiang, Sissy M.; Capen, Charles C.

2000-01-01

Papillary thyroid carcinomas in humans are associated with the ret/PTC oncogene and, following loss of p53 function, may progress to anaplastic carcinomas. Mice with thyroid-targeted expression of ret/PTC1 developed papillary thyroid carcinomas that were minimally invasive and did not metastasize. These mice were crossed with p53−/− mice to investigate whether loss of p53 would promote anaplasia and metastasis of ret/PTC1-induced thyroid tumors. The majority of p53−/− mice died or were euthanized by 17 weeks of age due to the development of thymic lymphomas, soft tissue sarcomas, and testicular teratomas. All ret/PTC1 mice developed thyroid carcinomas, but tumors in p53−/− mice were more anaplastic, larger in diameter, more invasive, and had a higher mitotic index than tumors in p53+/+ and p53+/− mice. Thyroid tumors did not metastasize in any of the experimental p53+/+ and p53+/− mice ≤28 weeks of age or p53−/− mice ≤ 17 weeks of age; however, an older (170-day-old) male p53−/− mouse used to maintain the colony developed anaplastic thyroid carcinoma with liver metastases. These findings demonstrate that the lack of functional p53 in ret/PTC1 mice promotes anaplasia and invasiveness of thyroid carcinomas. PMID:10934169

Changes of thyroid hormone levels and related gene expression in zebrafish on early life stage exposure to triadimefon.

PubMed

Liu, Shaoying; Chang, Juhua; Zhao, Ying; Zhu, Guonian

2011-11-01

In this study, zebrafish was exposed to triadimefon. Thyroid hormones levels and the expression of related genes in the hypothalamic-pituitary-thyroid (HPT) axis, including thyroid-stimulating hormone (TSH-beta), deiodinases (dio1 and dio2) and the thyroid hormone receptor (thraa and thrb) were evaluated. After triadimefon exposure, increased T4 can be explained by increased thyroid-stimulating hormone (TSH-beta). The conversion of T4 to T3 (deiodinase type I-dio1) was decreased, which reduced the T3 level. Thyroid hormone receptor beta (thrb) mRNA levels were significantly down-regulated, possibly as a response to the decreased T3 levels. The overall results indicated that triadimefon exposure could alter gene expression in the HPT axis and that mechanisms of disruption of thyroid status by triadimefon could occur at several steps in the synthesis, regulation, and action of thyroid hormones. Crown Copyright © 2011. Published by Elsevier B.V. All rights reserved.

The nuclear receptor corepressor (NCoR) controls thyroid hormone sensitivity and the set point of the hypothalamic-pituitary-thyroid axis.

PubMed

Astapova, Inna; Vella, Kristen R; Ramadoss, Preeti; Holtz, Kaila A; Rodwin, Benjamin A; Liao, Xiao-Hui; Weiss, Roy E; Rosenberg, Michael A; Rosenzweig, Anthony; Hollenberg, Anthony N

2011-02-01

The role of nuclear receptor corepressor (NCoR) in thyroid hormone (TH) action has been difficult to discern because global deletion of NCoR is embryonic lethal. To circumvent this, we developed mice that globally express a modified NCoR protein (NCoRΔID) that cannot be recruited to the thyroid hormone receptor (TR). These mice present with low serum T(4) and T(3) concentrations accompanied by normal TSH levels, suggesting central hypothyroidism. However, they grow normally and have increased energy expenditure and normal or elevated TR-target gene expression across multiple tissues, which is not consistent with hypothyroidism. Although these findings imply an increased peripheral sensitivity to TH, the hypothalamic-pituitary-thyroid axis is not more sensitive to acute changes in TH concentrations but appears to be reset to recognize the reduced TH levels as normal. Furthermore, the thyroid gland itself, although normal in size, has reduced levels of nonthyroglobulin-bound T(4) and T(3) and demonstrates decreased responsiveness to TSH. Thus, the TR-NCoR interaction controls systemic TH sensitivity as well as the set point at all levels of the hypothalamic-pituitary-thyroid axis. These findings suggest that NCoR levels could alter cell-specific TH action that would not be reflected by the serum TSH.

Thyroid organotypic rat and human cultures used to investigate drug effects on thyroid function, hormone synthesis and release pathways

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vickers, Alison E.M., E-mail: vickers_alison@allergan.com; Heale, Jason; Sinclair, John R.

Drug induced thyroid effects were evaluated in organotypic models utilizing either a rat thyroid lobe or human thyroid slices to compare rodent and human response. An inhibition of thyroid peroxidase (TPO) function led to a perturbation in the expression of key genes in thyroid hormone synthesis and release pathways. The clinically used thiourea drugs, methimazole (MMI) and 6-n-propyl-2-thioruacil (PTU), were used to evaluate thyroid drug response in these models. Inhibition of TPO occurred early as shown in rat thyroid lobes (2 h) and was sustained in both rat (24–48 h) and human (24 h) with ≥ 10 μM MMI. Thyroidmore » from rats treated with single doses of MMI (30–1000 mg/kg) exhibited sustained TPO inhibition at 48 h. The MMI in vivo thyroid concentrations were comparable to the culture concentrations (∼ 15–84 μM), thus demonstrating a close correlation between in vivo and ex vivo thyroid effects. A compensatory response to TPO inhibition was demonstrated in the rat thyroid lobe with significant up-regulation of genes involved in the pathway of thyroid hormone synthesis (Tpo, Dio1, Slc5a5, Tg, Tshr) and the megalin release pathway (Lrp2) by 24 h with MMI (≥ 10 μM) and PTU (100 μM). Similarly, thyroid from the rat in vivo study exhibited an up-regulation of Dio1, Slc5a5, Lrp2, and Tshr. In human thyroid slices, there were few gene expression changes (Slc5a5, ∼ 2-fold) and only at higher MMI concentrations (≥ 1500 μM, 24 h). Extended exposure (48 h) resulted in up-regulation of Tpo, Dio1 and Lrp2, along with Slc5a5 and Tshr. In summary, TPO was inhibited by similar MMI concentrations in rat and human tissue, however an increased sensitivity to drug treatment in rat is indicated by the up-regulation of thyroid hormone synthesis and release gene pathways at concentrations found not to affect human tissue. -- Highlights: ► Novel model of rat thyroid or human thyroid slices to evaluate pathways of injury. ► TPO inhibition by MMI or PTU altered hormone synthesis and release genes. ► Rat thyroid was more sensitive to the drug effects than human tissue.« less

EXPERIMENTAL THYROIDISM

PubMed Central

Cunningham, R. H.

1898-01-01

From the results of the various experiments already detailed I feel justified in drawing the following conclusions: (1) Absolutely fresh thyroid gland is not poisonous, in the usual sense of the term, when absorbed through the alimentary canal. (2) The symptoms of induced thyroidism are manifestations of an intoxication resulting from the ingestion of decomposed thyroid material, a conclusion that agrees in part with the previously related observations of Lanz. (3) The so-called experimental thyroidism is not specific for the thyroid only, for the ingestion of many substances derived from animal tissues other than the thyroid gland may produce an intoxication strikingly similar in every respect to that of experimental thyroidism. (4) Most, if not all, animal tissues yield substances which, if injected in large quantities directly into the circulation or beneath the skin, will produce an intoxication often very similar to that produced by injections of various substances derived from the fresh thyroid tissue. (5) The effects resulting from the intravascular or subcutaneous injections of aqueous extracts, decoctions and the concentrated extractives of the thyroid tissue, of the thymus, of muscle, etc., are by no means necessarily indicative of the function and the action of the hypothetical internal secretions of the same tissues during life. (6) The utilization of the fact that ingestion of decomposed thyroid material produces on certain occasions an intoxication with certain symptoms similar to some of those of G-raves' disease is not justifiable for the furtherance of the theory that the symptoms of exophthalmic goitre result from an over-production of the thyroid secretion. (7) Our results lead us to conclude with Drechsel that the fresh thyroid tissue yields at least probably two substances that are capable of palliating the symptoms of the acute cachexia in totally thyroidless dogs. (8) The thymus tissue also yields one and probably two substances that are as equally capable as the thyroid extractives of palliating the acute cachexia in totally thyroidless dogs. (9) Neither of the above substances is an enzyme, nor does either contain iodine. (10) Neither the feeding of minced raw thyroid glands, nor the injection of aqueous thyroid extracts, decoctions, and concentrated solutions of the extracted palliative thyroid principles is capable of keeping totally thyroidless young dogs alive longer than a few weeks (possibly three weeks). Still less capable are the thyroid preparations containing decomposition products. (11) The presence of one, or usually several, small accessory thyroid bodies, which gradually hypertrophy and wholly or partially assume the functions of the excised thyroid lobes, accounts for the occasionally long survival of thyroidectomized, thyroid-fed, young dogs. (12) Totally thyroidless young dogs are so quickly overwhelmed by the cachexia, and the intervals between the thyroidectomy and the onset of the severe dyspnœic attacks and subsequent deaths differ so slightly, no matter which of the usual varieties of fresh food are employed, that kinds of fresh food cannot be unquestionably affirmed to influence the onset of the cachexia in any especially definite manner. Animal foods, in which constituents poisonous to rabbits have developed, probably slightly hasten the onset of the severer symptoms, and the vaunted remarkably modifying influence of a diet of ordinary milk, such as Breisacher observed, does not exist in the case of the totally thyroidless dog. (13) Monkeys whose general metabolism is disturbed in consequence of the removal of a greater portion of the thyroid gland, evidently become more susceptible to those constituents of meat that are poisonous to rabbits, and sufficient clinical evidence exists for concluding that probably a like susceptibility to animal foods containing such constituents also exists in men when the function of the thyroid gland is sufficiently disturbed. (14) And, finally, as regards the thyroid factor in the pathology of exophthalmic goitre, I agree with Gley that the majority of the symptoms in many patients with that disease can apparently, from an experimental standpoint, be as plausibly explained by the hypothesis of partially deficient thyroid activity as by the hypothesis of augmentation of thyroid function. PMID:19866869

Hypothyroidism in utero stimulates pancreatic beta cell proliferation and hyperinsulinaemia in the ovine fetus during late gestation.

PubMed

Harris, Shelley E; De Blasio, Miles J; Davis, Melissa A; Kelly, Amy C; Davenport, Hailey M; Wooding, F B Peter; Blache, Dominique; Meredith, David; Anderson, Miranda; Fowden, Abigail L; Limesand, Sean W; Forhead, Alison J

2017-06-01

Thyroid hormones are important regulators of growth and maturation before birth, although the extent to which their actions are mediated by insulin and the development of pancreatic beta cell mass is unknown. Hypothyroidism in fetal sheep induced by removal of the thyroid gland caused asymmetric organ growth, increased pancreatic beta cell mass and proliferation, and was associated with increased circulating concentrations of insulin and leptin. In isolated fetal sheep islets studied in vitro, thyroid hormones inhibited beta cell proliferation in a dose-dependent manner, while high concentrations of insulin and leptin stimulated proliferation. The developing pancreatic beta cell is therefore sensitive to thyroid hormone, insulin and leptin before birth, with possible consequences for pancreatic function in fetal and later life. The findings of this study highlight the importance of thyroid hormones during pregnancy for normal development of the fetal pancreas. Development of pancreatic beta cell mass before birth is essential for normal growth of the fetus and for long-term control of carbohydrate metabolism in postnatal life. Thyroid hormones are also important regulators of fetal growth, and the present study tested the hypotheses that thyroid hormones promote beta cell proliferation in the fetal ovine pancreatic islets, and that growth retardation in hypothyroid fetal sheep is associated with reductions in pancreatic beta cell mass and circulating insulin concentration in utero. Organ growth and pancreatic islet cell proliferation and mass were examined in sheep fetuses following removal of the thyroid gland in utero. The effects of triiodothyronine (T 3 ), insulin and leptin on beta cell proliferation rates were determined in isolated fetal ovine pancreatic islets in vitro. Hypothyroidism in the sheep fetus resulted in an asymmetric pattern of organ growth, pancreatic beta cell hyperplasia, and elevated plasma insulin and leptin concentrations. In pancreatic islets isolated from intact fetal sheep, beta cell proliferation in vitro was reduced by T 3 in a dose-dependent manner and increased by insulin at high concentrations only. Leptin induced a bimodal response whereby beta cell proliferation was suppressed at the lowest, and increased at the highest, concentrations. Therefore, proliferation of beta cells isolated from the ovine fetal pancreas is sensitive to physiological concentrations of T 3 , insulin and leptin. Alterations in these hormones may be responsible for the increased beta cell proliferation and mass observed in the hypothyroid sheep fetus and may have consequences for pancreatic function in later life. © 2017 The Authors. The Journal of Physiology published by John Wiley & Sons Ltd on behalf of The Physiological Society.

Thyroid function alterations attributed to high iodide supplementation in maternal rats and their offspring.

PubMed

Liang, Xue; Feng, Yanni; Lin, Laixiang; Abeysekera, Iruni Roshanie; Iqbal, Umar; Wang, Tingting; Wang, Ying; Yao, Xiaomei

2018-05-01

Our aim was to investigate thyroid function alterations attributed to high iodide supplementation in maternal rats and their offspring. Depending on their iodide intake, the pregnant rats were randomly divided into three groups: normal iodide intake (NI), 10 times high iodide intake (10 HI) and 100 times high iodide intake (100 HI) groups. Iodine concentration in the urine and maternal milk; iodine content and mitochondrial superoxide production; expression of TRα1, TRβ1, NIS and Dio1 in both the thyroid and mammary glands were all measured. The offspring were exposed to different iodide-containing water (NI, 10 HI and 100 HI) from weaning to postnatal day 180 (PN180). Serum thyroid hormone levels were measured in both maternal rats and their offspring. Iodine concentration in the urine and maternal milk, as well as iodine content in the thyroid and mammary glands was significantly increased in both the 10 HI and 100 HI groups (p < .05). In the 100 HI group of maternal rats, low FT3 levels, high FT4, TPOAb and TgAb levels were detected. In addition, an increased mitochondrial superoxide production and decreased expression of TRα1, TRβ1, NIS and Dio1 in the thyroid and mammary glands was found (p < .05). A positive staining of CD4 + that co-localized with TRβ1 in the infiltrated cells within the thyroid follicles was observed. At PN180 in the offspring, the FT3 and FT4 levels showed a significant decrease, while the levels of serum TSH, TPOAb and TgAb were significantly increased in both 10 HI and 100 HI groups (p < .05). In maternal rats, although normal thyroid function can be maintained following 10 HI, thyroiditis can be induced following 100 HI on lactation days 7, 14, and 21. In the offspring at PN180, hypothyroidism complicated with thyroiditis can occur in both the 10 HI and 100 HI groups. Copyright © 2018 Elsevier GmbH. All rights reserved.

Microrna-199a-5p Functions as a Tumor Suppressor via Suppressing Connective Tissue Growth Factor (CTGF) in Follicular Thyroid Carcinoma.

PubMed

Sun, Dawei; Han, Shen; Liu, Chao; Zhou, Rui; Sun, Weihai; Zhang, Zhijun; Qu, Jianjun

2016-04-11

BACKGROUND The objective of this study was to explore the role of miR-199a-5p in the development of thyroid cancer, including its anti-proliferation effect and downstream signaling pathway. MATERIAL AND METHODS We conducted qRT-PCR analysis to detect the expressions of several microRNAs in 42 follicular thyroid carcinoma patients and 42 controls. We identified CTGF as target of miR-491, and viability and cell cycle status were determined in FTC-133 cells transfected with CTGF siRNA, miR-199a mimics, or inhibitors. RESULTS We identified an underexpression of miR-199a-5p in follicular thyroid carcinoma tissue samples compared with controls. Then we confirmed CTGF as a target of miR-199a-5p thyroid cells by using informatics analysis and luciferase reporter assay. Additionally, we found that mRNA and protein expression levels of CTGF were both clearly higher in malignant tissues than in benign tissues. miR-199a-5p mimics and CTGF siRNA similarly downregulated the expression of CTGF, and reduced the viability of FTC-133 cells by arresting the cell cycle in G0 phase. Transfection of miR-199a-5p inhibitors increased the expression of CTGF and promoted the viability of the cells by increasing the fraction of cells in G2/M and S phases. CONCLUSIONS Our study proves that the CTGF gene is a target of miR-199a-5p, demonstrating the negatively related association between CTGF and miR-199a. These findings suggest that miR-199a-5p might be a novel therapeutic target in the treatment of follicular thyroid carcinoma.

Acute thyrotoxicosis secondary to destructive thyroiditis associated with cardiac catheterization contrast dye.

PubMed

Calvi, Laura; Daniels, Gilbert H

2011-04-01

Thyrotoxicosis caused by destructive thyroiditis is self-limited and results from the subacute release of preformed thyroid hormone. Common etiologies include painful subacute thyroiditis and silent (painless) subacute thyroiditis (including postpartum thyroiditis, amiodarone-associated destructive thyroiditis, and lithium-associated thyroiditis). Thyrotoxicosis commonly evolves slowly over a matter of weeks. We report a unique case of severe thyrotoxicosis caused by acute- onset painful destructive thyroiditis in a patient who received large amounts of nonionic contrast dye Hexabrix® for cardiac catheterization. The results of thyroid function and physical examination were normal before the catheterization. The acute onset of severe thyroid pain, rapid increase in serum Free Thyroxine Index, and thyroglobulin concentrations with a triiodothyronine to free thyroxine index ratio of < 20 to 1 were compatible with an acute onset destructive thyroiditis, likely related to direct toxicity from the iodinated contrast material. In light of the large number of patients who receive these contrast agents during cardiac catheterization, clinicians should be advised of this potentially serious complication, particularly in the setting of unstable cardiac disease.

[Rare differential diagnosis of hyperthyroidism].

PubMed

Besemer, Britta; Müssig, Karsten

2016-06-01

A 54-year-old female patient is admitted for evaluation of her thyroid function after two cycles of ipilimumab therapy. The decision for the anti-cytotoxic-T-lymphocyte-antigen-4-therapy (anti-CTLA-4) was made two months earlier because of malignant melanoma with pulmonary metastases. The patient was euthyroid before initiation of treatment and without known thyroid disease. The laboratory reveals thyrotoxicosis with elevated anti-thyroid peroxidase and anti-thyroglobulin antibody levels. The anti-thyroid stimulating hormone receptor antibody levels are within the normal range. Thyroid ultrasound shows a normal-sized, inhomogenous, hypoechogenic thyroid gland, consistent with autoimmune thyroiditis. Diagnosis of hyperthyroidism due to ipilimumab-induced autoimmune thyroiditis is made. The patient does not receive any thyroid-specific medication, with regular control of the thyroid hormone levels. When the patient becomes euthyroid, the ipilimumab therapy is continued. Three weeks later, the patient develops hypothyroidism and a supplementation with L-thyroxine is initiated. An anti-CTLA-4 therapy may cause thyroid dysfunction. Therefore, before initiation and in the course of the treatment, regular controls of the thyroid hormone levels are required. © Georg Thieme Verlag KG Stuttgart · New York.

Microfollicular adenoma of ectopic thyroid gland masquerading as salivary gland tumor - a diagnostic and therapeutic challenge: a case report.

PubMed

Deshmukh, Sanjay D; Khandeparkar, Siddhi G Sinai; Gulati, Harveen K; Naik, Chetana S

2014-08-07

Ectopic thyroid tissue may appear in any location along the trajectory of the thyroglossal duct from the foramen cecum to the mediastinum. Rarely, there is incomplete descent of the gland where the final resting point may be high resulting in sublingual ectopic thyroid tissue. Ectopic thyroid tissue carries a low risk of malignancy. Most recently reported neoplasms in ectopic thyroid tissue have been papillary carcinoma of thyroid. Individual case reports of clear cell type of follicular adenoma within the ectopic thyroid tissue have been described in the literature. We present a rare case of microfollicular follicular adenoma in an ectopic sublingual thyroid tissue presenting as submental swelling in a euthyroid 24-year-old Dravidian woman. Findings in this case emphasize that when confronted with a submental/sublingual mass lesion, the evaluation of thyroid function tests and ultrasonography of the neck should be included in a pre-operative workup.

Differential Effects of Sepsis and Chronic Inflammation on Diaphragm Muscle Fiber Type, Thyroid Hormone Metabolism, and Mitochondrial Function.

PubMed

Bloise, Flavia F; van der Spek, Anne H; Surovtseva, Olga V; Ortiga-Carvalho, Tania Maria; Fliers, Eric; Boelen, Anita

2016-04-01

The diaphragm is the main respiratory muscle, and its function is compromised during severe illness. Altered local thyroid hormone (TH) metabolism may be a determinant of impaired muscle function during illness. This study investigates the effects of bacterial sepsis and chronic inflammation on muscle fiber type, local TH metabolism, and mitochondrial function in the diaphragm. Two mouse models were used: sepsis induced by S. pneumoniae infection or chronic inflammation induced by subcutaneous turpentine injection. In vitro, the effect of bacterial endotoxin (LPS) on mitochondrial function in C2C12 myotubes was studied. Sepsis induced a transient increase in the fiber type I profile and increased Dio3 expression while decreasing Dio2, Thra1, and Slc16a2 expression. Triiodothyronine positively regulated genes Tnni2 and Myog were decreased, indicating reduced TH signaling in the diaphragm. In contrast, chronic inflammation increased the fiber type II profile in the diaphragm as well as Thra1, Thrb1, and Myog expression while decreasing Dio3 expression, suggesting increased TH responsiveness during chronic inflammation. LPS-stimulated C2C12 myotubes showed decreased Dio2 expression and reduced basal oxygen consumption as well as non-mitochondrial respiration. The same respiratory profile was induced by Dio2 knockdown in myotubes. The in vivo results show differential effects of sepsis and chronic inflammation on diaphragm muscle fiber type, TH metabolism, and mitochondrial function, while the in vitro results point to a causal role for altered TH metabolism in functional muscle impairment. These findings may be relevant for the pathogenesis of impaired respiratory function in critical illness.

Thyroid tissue constituents characterization and application to in vivo studies by broadband (600-1200 nm) diffuse optical spectroscopy

NASA Astrophysics Data System (ADS)

Konugolu Venkata Sekar, Sanathana; Farina, Andrea; dalla Mora, Alberto; Taroni, Paola; Lindner, Claus; Mora, Mireia; Farzam, Parisa; Pagliazzi, Marco; Squarcia, Mattia; Halperin, Irene; Hanzu, Felicia A.; Dehghani, Hamid; Durduran, Turgut; Pifferi, Antonio

2017-07-01

We present the first broadband (600-1100 nm) diffuse optical characterization of thyroglobulin and tyrosine, which are thyroid-specific tissue constituents. In-vivo measurements at the thyroid region enabled their quantification for functional and diagnostic applications.

THYROID STATUS IN JUVENILE ALLIGATORS (ALLIGATOR MISSISSIPPIENSIS) FROM CONTAMINATED AND REFERENCE SITES ON LAKE OKEECHOBEE, FLORIDA, USA

EPA Science Inventory

Exposure to environmental contaminants has been shown to alter normal thyroid function in various wildlife species, including the American alligator (Alligator mississippiensis). Abnormalities in circulating levels of the thyroid hormone thyroxine (T4) have been reported in juven...

A Qualitative Comparison of Porcine and Rodent Thyroperoxidase -Effects of Environmental Chemicals.

EPA Science Inventory

A wide variety of environmental chemicals alter the function of the thyroid system in many animal species. Thyroperoxidase (TPO), the enzyme that synthesizes thyroid hormone, is one of the known biochemical targets for thyroid disrupting chemicals (TDC). The majority of the in vi...

[Pharmacological approaches for correction of thyroid dysfunctions in diabetes mellitus].

PubMed

Shpakov, A O

2017-05-01

Thyroid diseases are closely associated with the development of types 1 and 2 diabetes mellitus (DM), and as a consequence, the development of effective approaches for their treatment is one of the urgent problems of endocrinology. Traditionally, thyroid hormones (TH) are used to correct functions of the thyroid system. However, they are characterized by many side effects, such as their negative effect on the cardiovascular system as well as the ability of TH to enhance insulin resistance and to disturb insulin-producing function of pancreas, exacerbating thereby diabetic pathology. Therefore, the analogues of TH, selective for certain types of TH receptors, that do not have these side effects, are being developed. The peptide and low-molecular weight regulators of thyroid-stimulating hormone receptor, which regulate the activity of the thyroid axis at the stage of TH synthesis and secretion in thyrocytes, are being created. Systemic and intranasal administration of insulin, metformin therapy and drugs with antioxidant activity are effective for the treatment of thyroid pathology in types 1 and 2 DM. In the review, the literature data and the results of own investigations on pharmacological approaches for the treatment and prevention of thyroid diseases in patients with types 1 and 2 DM are summarized and analyzed.

Evaluation of thyroid dysfunction in pregnant women with gestational and pre-gestational diabetes.

PubMed

Shahbazian, Hajieh; Shahbazian, Nahid; Rahimi Baniani, Mahnaz; Yazdanpanah, Leila; Latifi, Seyed Mahmuod

2013-04-01

The aim of this study was to investigate thyroid function tests in Gestational Diabetes Mellitus (GDM) and pre-gestational DM and control group. Methodology : There were 61 pregnant diabetic women in study group and 35 pregnant women in control group. Serum T4, T3, T3RU, FTI, TSH and Anti TPO Ab were assessed in each person. Results : About 36% of patients had GDM and 64% pre-gestational DM. Thyroid dysfunction was detected in 18% of study group compared with 8.6% of control group (P = 0.2). There was Thyroid dysfunction in 4.5% of GDM and 25.6% of pregestational DM (P = 0.045). There was no statistically significant difference between thyroid dysfunction in GDM group and control group (P=0.99).27% of GDM and 36% of pregestational DM and 23% of control group had positive titer of Anti TPO Ab without statistically significant differences among the three groups. Conclusion : Thyroid dysfunction is prevalent in women with pre-gestational DM so, thyroid function should be evaluated in these patients during pregnancy. Rate of thyroid dysfunction in GDM patients is similar to normal pregnant control women. High prevalence of positive titer of TPO Ab was seen in diabetic and non-diabetic pregnant women.

Evaluation of thyroid dysfunction in pregnant women with gestational and pre-gestational diabetes

PubMed Central

Shahbazian, Hajieh; Shahbazian, Nahid; Rahimi Baniani, Mahnaz; Yazdanpanah, Leila; Latifi, Seyed Mahmuod

2013-01-01

Objective: The aim of this study was to investigate thyroid function tests in Gestational Diabetes Mellitus (GDM) and pre-gestational DM and control group. Methodology : There were 61 pregnant diabetic women in study group and 35 pregnant women in control group. Serum T4, T3, T3RU, FTI, TSH and Anti TPO Ab were assessed in each person. Results : About 36% of patients had GDM and 64% pre-gestational DM. Thyroid dysfunction was detected in 18% of study group compared with 8.6% of control group (P = 0.2). There was Thyroid dysfunction in 4.5% of GDM and 25.6% of pregestational DM (P = 0.045). There was no statistically significant difference between thyroid dysfunction in GDM group and control group (P=0.99).27% of GDM and 36% of pregestational DM and 23% of control group had positive titer of Anti TPO Ab without statistically significant differences among the three groups. Conclusion : Thyroid dysfunction is prevalent in women with pre-gestational DM so, thyroid function should be evaluated in these patients during pregnancy. Rate of thyroid dysfunction in GDM patients is similar to normal pregnant control women. High prevalence of positive titer of TPO Ab was seen in diabetic and non-diabetic pregnant women. PMID:24353594

Temporary ovarian failure in thyroid cancer patients after thyroid remnant ablation with radioactive iodine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raymond, J.P.; Izembart, M.; Marliac, V.

We studied ovarian function retrospectively in 66 women who had regular menstrual cycles before undergoing complete thyroidectomy for differentiated thyroid cancer and subsequent thyroid remnant ablation with /sup 131/I. Eighteen women developed temporary amenorrhea accompanied by increased serum gonadotropin concentrations during the first year after /sup 131/I therapy. No correlation was found between the radioactive iodine dose absorbed, thyroid uptake before treatment, oral contraceptive use, or thyroid autoimmunity. Only age was a determining factor, with the older women being the most affected. We conclude that radioiodine ablation therapy is followed by transient ovarian failure, especially in older women.

Hypothyroidism: etiology, diagnosis, and management.

PubMed

Almandoz, Jaime P; Gharib, Hossein

2012-03-01

Hypothyroidism is the result of inadequate production of thyroid hormone or inadequate action of thyroid hormone in target tissues. Primary hypothyroidism is the principal manifestation of hypothyroidism, but other causes include central deficiency of thyrotropin-releasing hormone or thyroid-stimulating hormone (TSH), or consumptive hypothyroidism from excessive inactivation of thyroid hormone. Subclinical hypothyroidism is present when there is elevated TSH but a normal free thyroxine level. Treatment involves oral administration of exogenous synthetic thyroid hormone. This review presents an update on the etiology and types of hypothyroidism, including subclinical disease; drugs and thyroid function; and diagnosis and treatment of hypothyroidism. Copyright © 2012 Elsevier Inc. All rights reserved.

Ultrasound and thyroiditis in patient candidates for thyroidectomy.

PubMed

Del Rio, P; De Simone, B; Fumagalli, M; Viani, L; Totaro, A; Sianesi, M

2015-03-01

Thyroiditis is often associated with nodules based on the Bethesda classification system, and the presence of thyroiditis can make thyroid surgery difficult using both conventional techniques and minimally invasive videoassisted approaches (MIVAT). We analyzed 326 patients who underwent total thyroidectomy in 2012. We collected all data in dedicated database. The patients were divided in 4 groups: group 1 no affected by thyroiditis, group 2 affected by thyroiditis, group 3 only histological diagnosis of thyroiditis, group 4all patients affected by thyroiditis. Group 1 included 201 cases, group 2 included 64 patients, group 3 included 61 patients. No statistically significant difference between group 2 and 3 about Ultrasound (US) examination. Statistically significant difference in incidence of "THYR 3-4" between group 1 and group 4. No differences in MIVAT vs. Conventional group. US examination of the thyroid is essential for the diagnostic study of the gland also in the selection of a surgical approach. Thyroiditis is a relative contraindication to MIVAT but the experience of the endocrine surgeon is the most important factor to reduce intra and postoperative complications together a correct collaboration in multidisciplinart endocrinological team.

Thyroid disease and the cardiovascular system.

PubMed

Danzi, Sara; Klein, Irwin

2014-06-01

Thyroid hormones, specifically triiodothyronine (T3), have significant effects on the heart and cardiovascular system. Hypothyroidism, hyperthyroidism, subclinical thyroid disease, and low T3 syndrome each cause cardiac and cardiovascular abnormalities through both genomic and nongenomic effects on cardiac myocytes and vascular smooth muscle cells. In compromised health, such as occurs in heart disease, alterations in thyroid hormone metabolism may further impair cardiac and cardiovascular function. Diagnosis and treatment of cardiac disease may benefit from including analysis of thyroid hormone status, including serum total T3 levels. Copyright © 2014 Elsevier Inc. All rights reserved.

[Serum thyroxine-binding protein for determining the functional state of the thyroid gland in pregnant women with endemic goiter].

PubMed

Korol'kova, O A; Cheremukhin, V I

1975-01-01

A determination was made of the hormone-forming capacity of the thyroid gland in pregnent women under conditions of goiter endemic at various periods of pregnancy by trimesters (123-in healthy pregnant women, 206-with euthyroid goiter of the I degree, 271-or II degree, 90-of the II degree, and 4-of the IV degree). A method of zonal electrophoresis in the medinal-veronal buffer was applied. Thyrofixin with I131 isotope (made in the USSR) was used. With increase of the periods of pregnancy and the degree of euthyroid hyperplasia of the thyroid gland and goiter the thyroid gland function became elevated irrespective of age.

Oral manifestations of thyroid disorders and its management

PubMed Central

Chandna, Shalu; Bathla, Manish

2011-01-01

The thyroid is the major regulator of metabolism and affects all of the bodily functions. Thyroid dysfunction is the second most common glandular disorder of the endocrine system which may rear its head in any system in the body including the mouth. The oral cavity is adversely affected by either an excess or deficiency of these hormones. Before treating a patient who has thyroid disorder, the endocrinologist needs to be familiar with the oral manifestations of thyroid dysfunctions. The patient with a thyroid dysfunction, as well as the patient taking medications for it, requires proper risk management before considering dental treatment by the dentist. Thus, communication of dentist with endocrinologist must be bidirectional, to maintain patient's oral and thyroid health. PMID:21966646

Is there still a role for thyroid scintigraphy in the workup of a thyroid nodule in the era of fine needle aspiration cytology and molecular testing?

PubMed Central

Moreno-Reyes, Rodrigo; Kyrilli, Aglaia; Lytrivi, Maria; Bourmorck, Carole; Chami, Rayan; Corvilain, Bernard

2016-01-01

Thyroid scintigraphy is now rarely used in the work-up of a thyroid nodule except in the presence of a low TSH value. Therefore, autonomously functioning thyroid nodules (AFTNs) with a normal TSH value are diagnosed only in the rare medical centers that continue to use thyroid scan systematically in the presence of a thyroid nodule. In this review, we discuss the prevalence of AFTN with a normal TSH level and the possible consequences of performing fine needle aspiration cytology (FNAC) in an undiagnosed AFTN. We also discuss the risk of malignant AFTN which may be higher than previously stated. PMID:27158470

Preoperative therapeutic apheresis for severe medically refractory amiodarone-induced thyrotoxicosis: a case report.

PubMed

Yamamoto, Jennifer; Dostmohamed, Hanifa; Schacter, Isanne; Ariano, Robert E; Houston, Donald S; Lewis, Brenda; Knoll, Colleen; Katz, Pamela; Zarychanski, Ryan

2014-06-01

Amiodarone is associated with thyroid dysfunction and life-threatening thyrotoxicosis. In medically refractory cases, or where medical therapy is contraindicated, thyroidectomy may be required. To decrease perioperative thyroid storm and to reduce overall surgical risk, apheresis may be considered preoperatively to restore euthyroidism. We report a 46-year-old female with a history of cardiac arrhythmia and tachycardia-induced cardiomyopathy for which she received amiodarone. Months after discontinuation of amiodarone, the patient presented with wide complex tachycardia and symptoms of thyrotoxicosis. Laboratory testing confirmed severe thyrotoxicosis which was subsequently refractory to medical therapy. Total thyroidectomy was required. Following a total of 10 apheresis treatments, thyroid hormone levels were reduced to near normal levels and the patient's symptoms improved. Thyroidectomy was performed without intraoperative or postoperative complication. In the setting of life-threatening, medically refractory amiodarone-induced thyrotoxicosis, therapeutic apheresis can effectively reduce thyroid hormone levels and restore a state of clinical and biochemical euthyroidism. © 2013 Wiley Periodicals, Inc.

Thyroid STAtus and 6-Year Mortality in Elderly People Living in a Mildly Iodine-Deficient Area: The Aging in the Chianti Area (InCHIANTI) Study

PubMed Central

Ceresini, Graziano; Ceda, Gian Paolo; Lauretani, Fulvio; Maggio, Marcello; Usberti, Elisa; Marina, Michela; Bandinelli, Stefania; Guralnik, Jack M.; Valenti, Giorgio; Ferrucci, Luigi

2013-01-01

Objectives The relationship between thyroid dysfunction and mortality in elderly subjects is still undefined. In this population study we tested the hypothesis that in older subjects, living in a mildly iodine-deficient area, thyroid dysfunction may be associated with increased mortality independent of potential confounders. Design Longitudinal study Setting Community-based Participants Total of 951 subjects aged 65 years and older Measurements Plasma thyrotropin (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) concentrations and demographic features were evaluated in participants of the Aging in the Chianti Area (InCHIANTI) study, aged 65 years or older. Participants were classified according to thyroid function test. Kaplan-Meier survival and Cox proportional hazards models adjusted for confounders were used in the analysis. Results A total of 819 participants were euthyroid, 83 had Subclinical hyperthyroidism (SHyper), and 29 had Subclinical hypothyroidism (SHypo). Overt Hypo- and Hyperthyroidism were found in 5 and 15 subjects, respectively. During a median of six-years of follow-up, N 210 deaths occurred (22.1 %) of which 98 (46.6%) due to cardiovascular causes. Kaplan–Meier analysis revealed higher overall mortality for SHyper (P<0.04) as compared to euthyroid subjects. After adjusting for multiple confounders, participants with SHyper (Hazard Ratio[HR]:1.65; 95% Confidence Interval [CI]: 1.02–2.69) had significantly higher all-cause mortality than those with normal thyroid function. No significant association was found between SHyper and cardiovascular mortality. In euthyroid subjects, TSH was found to be predictive of a reduced risk of all-cause mortality (HR: 0.76; 95% CI, 0.57–0.99) Conclusion SHyper is an independent risk factor for all-cause mortality in the older population. Low-normal circulating TSH should be carefully monitored in euthyroid elderly individuals. PMID:23647402

Chinese herbal medicines for hyperthyroidism.

PubMed

Zen, X X; Yuan, Y; Liu, Y; Wu, T X; Han, S

2007-04-18

Hyperthyroidism is a disease in which excessive amounts of thyroid hormones circulate in the blood. Patients, among other things suffer from tachycardia, warm moist skin and raised body temperature. The treatment of hyperthyroidism includes symptom relief and therapy with antithyroid medications, radioiodine and thyroidectomy. Medicinal herbs are used alone or in combination with antithyroid agents to treat hyperthyroidism in China and some other countries. To assess the effects of Chinese herbal medicines for treating hyperthyroidism. Studies were obtained from computerised searches of MEDLINE, EMBASE, The Cochrane Library, the Chinese Biomedical Database. Randomised controlled trials comparing the effects of Chinese herbal medicines alone with Chinese herbal medicines combined with antithyroid drugs, radioiodine or both. Three authors interviewed authors of all potentially relevant studies by telephone to verify randomisation procedures. One author entered data into a data extraction form and another author verified the results of this procedure. Thirteen relevant trials with 1770 participants were included. All of them were of low quality. Fifty-two studies still need to be assessed because the original authors could not be interviewed. None of these trials analysed mortality, health related quality of life, economic outcomes or compliance. Compared to antithyroid drugs alone the results showed that Chinese herbal medicines combined with antithyroid drugs may offer benefits in lowering relapse rates, reducing the incidence of adverse effects, relieving symptoms, improving thyroid antibody status and thyroid function. Two trials investigated Chinese herbal medicine versus radioiodine and reported improvements in anxiety, tachycardia and heat intolerance. However, thyroid function - with the exception of restored thyroid stimulating hormone (TSH) - was not significantly altered. The results suggest that traditional Chinese herbal medicines added to other routine treatment have a therapeutic potential for people with hyperthyroidism. However, due to methodological limitations, we could not identify a well-designed trial to provide strong evidence for Chinese traditional herbal medicine in the treatment of hyperthyroidism. Thus, we currently cannot recommend any single preparation or formulation for clinical use.

Ethylene thiourea: thyroid function in two groups of exposed workers.

PubMed Central

Smith, D M

1984-01-01

Ethylene thiourea is manufactured at one factory in the United Kingdom and is mixed into masterbatch rubber at another. Clinical examinations and thyroid function tests were carried out over a period of three years on eight process workers and five mixers and on matched controls. The results show that the exposed mixers, but not exposed process workers, have significantly lower levels of total thyroxine (T4) than the controls. One mixer had an appreciably raised level of thyroid stimulation hormone (TSH). PMID:6743584

Ethylene thiourea: thyroid function in two groups of exposed workers.

PubMed

Smith, D M

1984-08-01

Ethylene thiourea is manufactured at one factory in the United Kingdom and is mixed into masterbatch rubber at another. Clinical examinations and thyroid function tests were carried out over a period of three years on eight process workers and five mixers and on matched controls. The results show that the exposed mixers, but not exposed process workers, have significantly lower levels of total thyroxine (T4) than the controls. One mixer had an appreciably raised level of thyroid stimulation hormone (TSH).

The Hypothalamic-Pituitary-Thyroid (HPT) Axis in Frogs and its Role in Frog Development and Reproduction

EPA Science Inventory

Metamorphosis of the amphibian tadpole is a thyroid hormone (TH)-dependent developmental process. For this reason, the tadpole is considered to be an ideal bioassay system to identify disruption of thyroid function by environmental contaminants. Here we provide an in-depth review...

HPLC-ICP/MS Analysis of Thyroid Hormone and Related Iodinated Compounds in Tissues and Media

EPA Science Inventory

Quantifying thyroid hormone (TH) and the synthetic precursors and metabolic products of TH is important for developing models of the hypothalamic-pituitary-thyroid (HPT) axis as well as for understanding the effects of xenobiotics on HPT axis function. In this study, the developm...

METAMORPHIC INHIBITION OF XENOPUS LAEVIS BY SODIUM PERCHLORATE: EFFECTS ON DEVELOPMENT AND THYROID HISTOLOGY

EPA Science Inventory

The perchlorate anion inhibits thyroid hormone (TH) synthesis via inhibition of the sodium-iodide symporter. It is, therefore, a good model chemical to aid in the development of a bioassay to screen chemicals for effects on thyroid function. Xenopus laevis larvae were exposed to ...

Atherosclerosis affecting vision: therapy.

PubMed

Eggers, H

1966-05-01

The visual consequences and the pathogenesis and therapy of atherosclerosis are discussed. Atherosclerosis apparently is the result of hepatic failure to produce a stable suspension of cholesterol esters in the plasma. In some instances this represents an inherent metabolic defect. Usually it represents improper diet, namely, the excessive intake of saturated fatty acids and the inadequate intake of polyunsaturated fatty acids. Excessive ingestion of carbohydrates, insufficient physical exercise and reduced thyroid function are contributing causes. The final common denominators leading to tissue injury and destruction are vascular insufficiency and hypoxia. Hypertension is a separate disease, often concurrent with atherosclerosis. In diabetes, also a separate disease, atherosclerosis is one of the sequelae. Therapy primarily consists of the reduction or elimination of meat and milk fats from the diet, and the inclusion or increase of marine fats and vegetable oils. Simultaneously, carbohydrate intake is restricted. Adequate thyroid function, a normal hemoglobin level, and sufficient physical exercise are important. A supplementary intake of vitamins B6 and E, and of lipotropic substances is recommended.

Hyperfunctioning solid/trabecular follicular carcinoma of the thyroid gland.

PubMed

Giovanella, Luca; Fasolini, Fabrizio; Suriano, Sergio; Mazzucchelli, Luca

2010-01-01

A 68-year-old woman with solid/trabecular follicular thyroid carcinoma inside of an autonomously functioning thyroid nodule is described in this paper. The patient was referred to our clinic for swelling of the neck and an increased pulse rate. Ultrasonography showed a slightly hypoechoic nodule in the right lobe of the thyroid. Despite suppressed TSH levels, the (99m)Tc-pertechnetate scan showed a hot area corresponding to the nodule with a suppressed uptake in the remaining thyroid tissue. Histopathological examination of the nodule revealed a solid/trabecular follicular thyroid carcinoma. To the best of our knowledge, this is the first case of hyperfunctioning follicular solid/trabecular carcinoma reported in the literature. Even if a hyperfunctioning thyroid carcinoma is an extremely rare malignancy, careful management is recommended so that a malignancy will not be overlooked in the hot thyroid nodules.

Mapping fundamental life elements in papillary thyroid carcinoma tissue

NASA Astrophysics Data System (ADS)

Merolle, L.; Ragazzi, M.; Gianoncelli, A.; Altissimo, M.; Ciarrocchi, A.; Bedolla, D. E.; Marraccini, C.; Baricchi, R.; Pertinhez, T. A.

2018-05-01

Well-differentiated papillary thyroid carcinomas (PTCs) are the most common type of thyroid cancer. Thyroid function depends on the presence of certain trace elements necessary for both the synthesis and the metabolism of thyroid hormones. We conducted an observational translational study on formalin fixed paraffin embedded thyroid tissue slices collected from five patients who underwent surgical resection of thyroid gland after thyroid cancer diagnosis. A synchrotron-based XRF set up was used to map the distribution of oxygen, sodium, aluminum, selenium and magnesium in PTC sections. These experiments were performed at the TwinMic beamline (Elettra—Sincrotrone Trieste, Trieste, Italy). Our results show that Mg levels in PTC tissues are significantly higher than in the control ones. The results seem to provide highly valuable information suggesting that Mg may play a role in the development and metabolic process of PTC.

Maternal thyroid function in women undergoing controlled ovarian hyperstimulation during in-vitro fertilization and its relation to reproductive outcome.

PubMed

Abdul Karim, Abdul K; Azrai Abu, Muhammad; Chelliah, Buvanes; Mohd Razi, Zainul R; Omar, Mohd H; Othman, Hanita; Man, Zuraidah C

2017-10-01

We conducted a study to evaluate the changes in thyroid function during controlled ovarian hyperstimulation (COH) and its association with the outcome of assisted reproductive technique (ART). This is a prospective cohort study done in University Hospital Fertility Clinic for one year duration. A total of 88 euthyroid women who underwent COH as part of planned in-vitro fertilization (IVF) were invited to participate in this study. Serum thyroid function of each women will be monitored before stimulation (T1), day 10-13 of cycle (T2), during oocyte retrieval (T3), one week following embryo transfer (T4), and at four weeks after embryo transfer (T5). Reproductive outcome of IVF will be observed and documented. Nine women had ongoing singleton pregnancy, seven suffered from miscarriage, while the rest had implantation failure. Serum thyroid-stimulating hormone (TSH) and free thyroxine (fT4) increased throughout stimulation, peaking at 32-36 hours after hCG administration compared to baseline (1.250 vs. 1.740 mIU/L and 13.94 vs. 15.25 pmol/L). It remains elevated until one week following embryo transfer. The increment of serum TSH exceeded the upper limit, acceptable for first trimester (<1.60 mIU/L). However, the evolution of serum TSH and fT4 did not significantly differ with pregnancy outcome. In euthyroid women, thyroid function changed significantly during COH, but these changes were not different between the three reproductive outcomes. Thus, we do not suggest continuous thyroid function monitoring during COH.

Association of transient hyperthyroidism and severity of hyperemesis gravidarum.

PubMed

Malek, Nor Zila Hassan; Kalok, Aida; Hanafiah, Zainal Abidin; Shah, Shamsul Azhar; Ismail, Nor Azlin Mohamed

2017-03-23

Background Transient non-immune hyperthyroidism in early pregnancy is hyperthyroidism diagnosed for the first time in early pregnancy, without evidence of thyroid autoimmunity or clinical findings of Grave's disease and resolved spontaneously as the pregnancy progressed. Hyperemesis gravidarum (HG) is the commonest cause with 66%-73% of women with severe HG were found to have elevated thyroid function. Materials and methods We conducted a cross sectional study to determine the prevalence of transient hyperthyroidism in patients with hyperemesis gravidarum and its relation to the severity of nausea and vomiting. Severity of nausea and vomiting in pregnancy was assessed using the modified pregnancy-unique quantification of emesis (PUQE) scoring system. Each patient had urine and blood investigations which also included a full blood count and thyroid and renal function tests. Patients with abnormal thyroid function were retested at 20 weeks of gestation. The patients' demographic data, electrolyte levels, thyroid function and their respective PUQE score were analyzed. Results The prevalence of transient hyperthyroidism in women with hyperemesis gravidarum was 4.8%. Although there was a significant association between the severity of the PUQE score and hypokalemia (p = 0.001), there was no significant association with transient hyperthyroidism in early pregnancy (p = 0.072). Free T4 and TSH values of all women with transient hyperthyroidism were normalized by 20 weeks of gestation. Conclusion Transient hyperthyroidism in pregnancy is not significantly associated with the severity of the PUQE score. Women with transient hyperthyroidism in pregnancy are normally clinically euthyroid, hence a routine thyroid function test is unnecessary unless they exhibit clinical signs or symptoms of hyperthyroidism.

Differential Regulation of Thyroid Hormone Metabolism Target Genes during Non-thyroidal Illness Syndrome Triggered by Fasting or Sepsis in Adult Mice

PubMed Central

Fontes, Klaus N.; Cabanelas, Adriana; Bloise, Flavia F.; de Andrade, Cherley Borba Vieira; Souza, Luana L.; Wilieman, Marianna; Trevenzoli, Isis H.; Agra, Lais C.; Silva, Johnatas D.; Bandeira-Melo, Christianne; Silva, Pedro L.; Rocco, Patricia R. M.; Ortiga-Carvalho, Tania M.

2017-01-01

Fasting and sepsis induce profound changes in thyroid hormone (TH) central and peripheral metabolism. These changes affect TH action and are called the non-thyroidal illness syndrome (NTIS). To date, it is still debated whether NTIS represents an adaptive response or a real hypothyroid state at the tissue level. Moreover, even though it has been considered the same syndrome, we hypothesized that fasting and sepsis induce a distinct set of changes in thyroid hormone metabolism. Herein, we aimed to evaluate the central and peripheral expression of genes involved in the transport (MCT8/Slc16a2 and MCT10/Slc16a10), metabolism (Dio1, Dio2, and Dio3) and action (Thra and Thrb) of TH during NTIS induced by fasting or sepsis. Male mice were subjected to a 48 h period of fasting or cecal ligation and puncture (CLP)-induced sepsis. At the peripheral level, fasting led to: (1) reduced serum thyroxine (T4) and triiodothyronine (T3), expression of Dio1, Thra, Slc16a2, and MCT8 protein in liver; (2) increased hepatic Slc16a10 and Dio3 expression; and (3) decreased Slc16a2 and Slc16a10 expressions in the thyroid gland. Fasting resulted in reduction of Tshb expression in the pituitary and increased expression of Dio2 in total hypothalamus, arcuate (ARC) and paraventricular (PVN) nucleus. CLP induced sepsis resulted in reduced: (1) T4 serum levels; (2) Dio1, Slc16a2, Slc16a10, Thra, and Thrb expression in liver as well as Slc16a2 expression in the thyroid gland (3) Thrb and Tshb mRNA expression in the pituitary; (4) total leukocyte counts in the bone marrow while increased its number in peritoneal and pleural fluids. In summary, fasting- or sepsis-driven NTIS promotes changes in the set point of hypothalamus-pituitary-thyroid axis through different mechanisms. Reduced hepatic THRs expression in conjunction with reduced TH transporters expression in the thyroid gland may indicate, respectively, reduction in the peripheral action and in the secretion of TH, which may contribute to the low TH serum levels observed in both models. PMID:29118715

Zebrafish hhex, nk2.1a, and pax2.1 regulate thyroid growth and differentiation downstream of Nodal-dependent transcription factors.

PubMed

Elsalini, Osama A; von Gartzen, Julia; Cramer, Matthias; Rohr, Klaus B

2003-11-01

During zebrafish development, the thyroid primordium initiates expression of molecular markers such as hhex and nk2.1a in the endoderm prior to pharynx formation. As expected for an endodermally derived organ, initiation of thyroid development depends on Nodal signalling. We find that it also depends on three downstream effectors of Nodal activity, casanova (cas), bonnie and clyde (bon), and faust (fau)/gata5. Despite their early Nodal-dependent expression in the endoderm, both hhex and nk2.1a are only required relatively late during thyroid development. In hhex and nk2.1a loss-of-function phenotypes, thyroid development is initiated and arrests only after the primordium has evaginated from the pharyngeal epithelium. Thus, like pax2.1, both hhex and nk2.1a have similarly late roles in differentiation or growth of thyroid follicular cells, and here, we show that all three genes act in parallel rather than in a single pathway. Our functional analysis suggests that these genes have similar roles as in mammalian thyroid development, albeit in a different temporal mode of organogenesis.

Risk Factors for New Hypothyroidism During Tyrosine Kinase Inhibitor Therapy in Advanced Nonthyroidal Cancer Patients.

PubMed

Lechner, Melissa G; Vyas, Chirag M; Hamnvik, Ole-Petter R; Alexander, Erik K; Larsen, P Reed; Choueiri, Toni K; Angell, Trevor E

2018-04-01

Thyroid dysfunction during tyrosine kinase inhibitor (TKI) cancer treatment is common, but predisposing risk factors have not been determined. Recommendations for monitoring patients treated with one or multiple TKI and in conjunction with other relevant cancer therapies could be improved. The study objective was to assess the risk factors for new thyroid dysfunction in TKI-treated previously euthyroid cancer patients. A retrospective cohort study of patients with advanced nonthyroidal cancer treated with TKI from 2000 to 2017, having available thyroid function tests showing initial euthyroid status, excluding patients with preexisting thyroid disease or lack of follow-up thyroid function tests. During TKI treatment, patients were classified as euthyroid (thyrotropin [TSH] normal), subclinical hypothyroidism (TSH 5-10 mIU/L, or higher TSH if free thyroxine normal), or overt hypothyroidism (TSH >10 mIU/L, low free thyroxine, or requiring thyroid hormone replacement). The timing of thyroid dysfunction and TKI used were assessed. Risk factors for incident hypothyroidism were evaluated using multivariate models. In 538 adult patients included, subclinical hypothyroidism occurred in 71 (13.2%) and overt hypothyroidism occurred in 144 (26.8%) patients with TKI therapy, following a median cumulative TKI exposure of 196 days (interquartile range [IQR] 63.5-518.5 days). The odds of hypothyroidism were greatest during the first six months on a TKI. Median exposure time on the TKI concurrent with thyroid dysfunction in patients treated with only one TKI was 85 days (IQR 38-293.5 days) and was similar to the 74 days (IQR 38-133.3 days) in patients treated previously with other TKI (p = 0.41). Patients who developed hypothyroidism compared to those who remained euthyroid had greater odds of being female (odds ratio = 1.99 [confidence interval 1.35-2.93], p < 0.01), but greater cumulative TKI exposure and greater number of TKI received were not associated with thyroid dysfunction. Thyroid dysfunction occurred in 40% of euthyroid patients. Monitoring thyroid function in TKI-treated patients is recommended, with particular attention to female patients and within the first six months of exposure to a new TKI.

Zn(II)-curc targets p53 in thyroid cancer cells.

PubMed

Garufi, Alessia; D'Orazi, Valerio; Crispini, Alessandra; D'Orazi, Gabriella

2015-10-01

TP53 mutation is a common event in many cancers, including thyroid carcinoma. Defective p53 activity promotes cancer resistance to therapies and a more malignant phenotype, acquiring oncogenic functions. Rescuing the function of mutant p53 (mutp53) protein is an attractive anticancer therapeutic strategy. Zn(II)-curc is a novel small molecule that has been shown to target mutp53 protein in several cancer cells, but its effect in thyroid cancer cells remains unclear. Here, we investigated whether Zn(II)-curc could affect p53 in thyroid cancer cells with both p53 mutation (R273H) and wild-type p53. Zn(II)-curc induced mutp53H273 downregulation and reactivation of wild-type functions, such as binding to canonical target promoters and target gene transactivation. This latter effect was similar to that induced by PRIMA-1. In addition, Zn(II)-curc triggered p53 target gene expression in wild-type p53-carrying cells. In combination treatments, Zn(II)-curc enhanced the antitumor activity of chemotherapeutic drugs, in both mutant and wild-type-carrying cancer cells. Taken together, our data indicate that Zn(II)-curc promotes the reactivation of p53 in thyroid cancer cells, providing in vitro evidence for a potential therapeutic approach in thyroid cancers.

Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes

PubMed Central

Aakre, Inger; Strand, Tor A.; Bjøro, Trine; Norheim, Ingrid; Barikmo, Ingrid; Ares, Susana; Alcorta, Marta Duque; Henjum, Sigrun

2016-01-01

Iodine excess may impair thyroid function and trigger adverse health consequences for children. This study aims to describe iodine status among breastfed infants with high iodine exposure in the Saharawi refugee camps Algeria, and further assess thyroid function and iodine status among the children three years later. In 2010, a cross-sectional study among 111 breastfed children aged 0–6 months was performed (baseline study). In 2013, a second cross-sectional study (follow-up study) was conducted among 289 children; 213 newly selected and 76 children retrieved from baseline. Urinary iodine concentration (UIC) and breast milk iodine concentration (BMIC) were measured at baseline. UIC, thyroid hormones and serum thyroglobulin (Tg) were measured at follow-up. At baseline and follow-up, 88% and 72% had excessive iodine intakes (UIC ≥ 300 µg/L), respectively. At follow-up, 24% had a thyroid hormone disturbance and/or elevated serum Tg, including 9% with subclinical hypothyroidism (SCH), 4% with elevated fT3 and 14% with elevated Tg. Children with SCH had poorer linear growth and were more likely to be underweight than the children without SCH. Excessive iodine intakes and thyroid disturbances were common among children below four years of age in our study. Further, SCH seemed to be associated with poor growth and weight. PMID:27367720

Thyroid Functions and Bipolar Affective Disorder

PubMed Central

Chakrabarti, Subho

2011-01-01

Accumulating evidence suggests that hypothalamo-pituitary-thyroid (HPT) axis dysfunction is relevant to the pathophysiology and clinical course of bipolar affective disorder. Hypothyroidism, either overt or more commonly subclinical, appears to the commonest abnormality found in bipolar disorder. The prevalence of thyroid dysfunction is also likely to be greater among patients with rapid cycling and other refractory forms of the disorder. Lithium-treatment has potent antithyroid effects and can induce hypothyroidism or exacerbate a preexisting hypothyroid state. Even minor perturbations of the HPT axis may affect the outcome of bipolar disorder, necessitating careful monitoring of thyroid functions of patients on treatment. Supplementation with high dose thyroxine can be considered in some patients with treatment-refractory bipolar disorder. Neurotransmitter, neuroimaging, and genetic studies have begun to provide clues, which could lead to an improved understanding of the thyroid-bipolar disorder connection, and more optimal ways of managing this potentially disabling condition. PMID:21808723

[Hypothyreodism. From the latent functional disorder up to coma].

PubMed

Hintze, G; Derwahl, M

2010-05-01

An autoimmune thyroiditis represents the main reason of hypothyroidism, defined as a lack of thyroid hormone. This autoimmune process results in destruction of functioning thyroid follicles. While subclinical or latent hypothyroidism is defined on the basis of laboratory values (an elevation of TSH with normal peripheral hormone levels), the typical signs and symptoms are associated with hypothyroidism. In about 80% of cases antibodies against thyroid peroxidase can be measured, but only in about 40-50% of cases antibodies against thyroglobulin are detectable. If hypothyrodism has been diagnosed, substitution with levothyroxine should be initiated, with the therapeutic goal to decrease TSH level to the lower normal range. In cases of subclinical hypothyroidism, levothyroxine medication should be started in patients with a high TSH value, positive antibodies and/or the typical ultrasound of autoimmune thyroiditis. However, substitution with levothyroxine in any case of elevated TSH values should be avoided.

CHIP promotes thyroid cancer proliferation via activation of the MAPK and AKT pathways.

PubMed

Zhang, Li; Liu, Lianyong; He, Xiaohua; Shen, Yunling; Liu, Xuerong; Wei, Jing; Yu, Fang; Tian, Jianqing

2016-08-26

The carboxyl terminus of Hsp70-interacting protein (CHIP) is a U box-type ubiquitin ligase that plays crucial roles in various biological processes, including tumor progression. To date, the functional mechanism of CHIP in thyroid cancer remains unknown. Here, we obtained evidence of upregulation of CHIP in thyroid cancer tissues and cell lines. CHIP overexpression markedly enhanced thyroid cancer cell viability and colony formation in vitro and accelerated tumor growth in vivo. Conversely, CHIP knockdown impaired cell proliferation and tumor growth. Notably, CHIP promoted cell growth through activation of MAPK and AKT pathways, subsequently decreasing p27 and increasing cyclin D1 and p-FOXO3a expression. Our findings collectively indicate that CHIP functions as an oncogene in thyroid cancer, and is therefore a potential therapeutic target for this disease. Copyright © 2016 Elsevier Inc. All rights reserved.

Transcriptional response to 131I exposure of rat thyroid gland.

PubMed

Rudqvist, Nils; Spetz, Johan; Schüler, Emil; Parris, Toshima Z; Langen, Britta; Helou, Khalil; Forssell-Aronsson, Eva

2017-01-01

Humans are exposed to 131I in medical diagnostics and treatment but also from nuclear accidents, and better knowledge of the molecular response in thyroid is needed. The aim of the study was to examine the transcriptional response in thyroid tissue 24 h after 131I administration in rats. The exposure levels were chosen to simulate both the clinical situation and the case of nuclear fallout. Thirty-six male rats were i.v. injected with 0-4700 kBq 131I, and killed at 24 h after injection (Dthyroid = 0.0058-3.0 Gy). Total RNA was extracted from individual thyroid tissue samples and mRNA levels were determined using oligonucleotide microarray technique. Differentially expressed transcripts were determined using Nexus Expression 3.0. Hierarchical clustering was performed in the R statistical computing environment. Pathway analysis was performed using the Ingenuity Pathway Analysis tool and the Gene Ontology database. T4 and TSH plasma concentrations were measured using ELISA. Totally, 429 differentially regulated transcripts were identified. Downregulation of thyroid hormone biosynthesis associated genes (e.g. thyroglobulin, thyroid peroxidase, the sodium-iodine symporter) was identified in some groups, and an impact on thyroid function was supported by the pathway analysis. Recurring downregulation of Dbp and Slc47a2 was found. Dbp exhibited a pattern with monotonous reduction of downregulation with absorbed dose at 0.0058-0.22 Gy. T4 plasma levels were increased and decreased in rats whose thyroids were exposed to 0.057 and 0.22 Gy, respectively. Different amounts of injected 131I gave distinct transcriptional responses in the rat thyroid. Transcriptional response related to thyroid function and changes in T4 plasma levels were found already at very low absorbed doses to thyroid.

Thyroid function and cold acclimation in the hamster, Mesocricetus auratus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tomasi, T.E.; Horwitz, B.A.

1987-02-01

Basal metabolic rate (BMR), thyroxine utilization rate (T4U), and triiodothyronine utilization rate (T3U) were measured in cold-acclimated (CA) and room temperature-acclimated (RA) male golden hamsters, Mesocricetus auratus. Hormone utilization rates were calculated via the plasma disappearance technique using SVI-labeled hormones and measuring serum hormone levels via radioimmunoassay. BMR showed a significant 28% increase with cold acclimation. The same cold exposure also produced a 32% increase in T4U, and a 204% increase in T3U. The much greater increase in T3U implies that previous assessments of the relationship between cold acclimation and thyroid function may have been underestimated and that cold exposuremore » induces both quantitative and qualitative changes in thyroid function. It is concluded that in the cold-acclimated state, T3U more accurately reflects thyroid function than does T4U. A mechanism for the cold-induced change in BMR is proposed.« less

Clinical course of thyroid function and thyroid associated-ophthalmopathy in patients with euthyroid Graves' disease.

PubMed

Suzuki, Nami; Noh, Jaeduk Yoshimura; Kameda, Toshiaki; Yoshihara, Ai; Ohye, Hidemi; Suzuki, Miho; Matsumoto, Masako; Kunii, Yo; Iwaku, Kenji; Watanabe, Natsuko; Mukasa, Koji; Kozaki, Ai; Inoue, Toshu; Sugino, Kiminori; Ito, Koichi

2018-01-01

Euthyroid Graves' disease (EGD) is a rare condition defined as the presence of thyroid-associated ophthalmopathy (TAO) in patients with normal thyroid function. Due to the rarity of this disease, only a limited number of studies and case reports are available for further evaluation of the characteristics of the disease. The aim of this study was to examine the changes in the thyroid function, thyrotropin receptor antibodies (TRAb) and eye symptoms, and then determine whether TRAb is related to TAO in EGD patients. TRAb in this study was defined as including both thyrotropin-binding inhibitory immunoglobulin (TBII) and thyroid-stimulating immunoglobulin (TSAb). Medical records of patients diagnosed with EGD were reviewed. Ophthalmologists specializing in TAO examined the eyes of all subjects. Of the 58 patients diagnosed with EGD, 24.1% developed hyperthyroidism, while 3.4% developed hypothyroidism. A total of 72.4% of the 58 patients remained euthyroid throughout the entire follow-up period. At the initial presentation, TBII and TSAb were positive in 74.5% and 70.5%, respectively. Ophthalmic treatments were administered to 30 (51.7%) out of the 58 patients. A significant spontaneous improvement of the eye symptoms was found in 28 of the EGD patients who did not require eye treatments. EGD patients exhibited positive rates for both TBII and TSAb, with the number of the TRAb-positive patients gradually decreasing while the eye symptoms spontaneously improved over time. There were no correlations found between TRAb at initial presentation and the eye symptoms. TBII and TSAb were positive in about 70% of EGD patients at their initial visit. Thyroid functions of EGD patients who have been euthyroid for more than 6.7 years may continue to remain euthyroid in the future.

High Iodine and Salt Intakes and Obesity do not Modify the Thyroid Function in Mexican Schoolchildren.

PubMed

Méndez-Villa, Lorena; García-Solís, Pablo; Solís-S, Juan Carlos; García-Gutiérrez, David Gustavo; Pérez-Mora, Valeria Alejandra; Robles-Osorio, Ludivina; Sampson-Zaldívar, Eduardo

2016-08-01

Mexico is considered as a nutritional transition country with a high prevalence of overweight and obesity, and recent studies have reported a high iodine intake in children. Both high iodine intake and obesity have been associated with thyroid dysfunction. Our aim was to assess iodine and salt intake and thyroid function in Mexican schoolchildren with normal weight and obesity. A cross-sectional study was performed during 2012-2013 in schoolchildren from Queretaro, Mexico. Six hundred seventy-eight schoolchildren were evaluated to obtain nutrition status, urinary iodine concentration (UIC) and thyroid volume (TVol). The prevalence of overweight and obesity was 47.3 %, the median UIC was 428 μg/L and TVol was normal in all schoolchildren; however, obese girls had a higher TVol than normal weight at the age of 8, 10 and 12 years. A subsample of schoolchildren was divided in 6-8 and 9-12-year-old groups, in order to compare thyroid function (thyrotropin, free T4, and anti-thyroid antibodies); iodine and salt intake were estimated with 24-h urinary samples. No differences in thyroid function were observed in both age groups. In the 6-8-year-old group, obese schoolchildren had higher iodine intake than normal-weight children (415.5 vs. 269.1 μg/day, p < 0.05), but no differences in salt intake. In contrast, in the 9-12-year-old group, obese schoolchildren had higher salt intake than normal-weight children (6.2 vs. 3.8 g/day, p < 0.05), but no differences in iodine intake. Dietary patterns could explain the differences between both age groups. Further studies are needed to identify the main sources of iodine intake in Mexican populations.

Thyroid Disorders Associated with Alopecia Areata in Egyptian Patients

PubMed Central

Bakry, Ola A; Basha, Mohamed A; El Shafiee, Maather K; Shehata, Wafaa A

2014-01-01

Context: Alopecia areata (AA) is a common form of localized, non-scarring hair loss. The etiopathogenesis of the disease is still unclear, but the role of autoimmunity is strongly suggested. AA is commonly associated with various autoimmune disorders; the most frequent among them is autoimmune thyroid disorders. Aim: To determine whether AA is associated with thyroid autoimmunity or thyroid function abnormalities in Egyptian patients. Materials and Methods: Fifty subjects with AA (37 males and 13 females) without clinical evidence of thyroid disorders were selected from Dermatology Outpatient Clinic, Menoufiya University Hospital, Menoufiya Governorate, Egypt, during the period from June 2009 to February 2010. They were divided into 3 groups according to severity of AA. Fifty age and sex-matched healthy volunteers (35 males and 15 females) were selected as a control group. Every case and control were subjected to history taking, complete general and dermatological examination. Venous blood samples were taken from cases and controls after taking their consents for measurement of thyroid stimulating hormone (TSH), free T3, freeT4 and detection of Anti-thyroglobulin Antibody (Tg-Ab) and Anti-thyroid Peroxidase Antibody (TPO-Ab). Results: Subclinical hypothyroidism was detected in 16% of cases. There were statistically significant differences between cases and controls regarding levels of TSH, free T3 and free T4. There were significant differences between cases and controls regarding the presence of Tg-Ab and TPO-Ab. Conclusions: Every patient with AA should be screened for thyroid functions and presence of thyroid autoantibodies even in absence of clinical manifestations suggestive of thyroid affection. PMID:24470660

Thyroid function abnormalities and cognitive impairment in elderly people: results of the Invecchiare in Chianti study.

PubMed

Ceresini, Graziano; Lauretani, Fulvio; Maggio, Marcello; Ceda, Gian Paolo; Morganti, Simonetta; Usberti, Elisa; Chezzi, Carlo; Valcavi, Rita; Bandinelli, Stefania; Guralnik, Jack M; Cappola, Anne R; Valenti, Giorgio; Ferrucci, Luigi

2009-01-01

To investigate thyroid function testing abnormalities in older persons and to explore the relationship between thyroid dysfunction and cognition. Cross-sectional. Community-based. One thousand one hundred seventy-one men and women aged 23 to 102. Thyroid function was evaluated by measuring plasma concentrations of thyrotropin (TSH), free thyroxine (FT4), and free triiodothyronine (FT3). Cognition was evaluated using the Mini-Mental State Examination (MMSE). Prevalence of overt and subclinical thyroid dysfunction was evaluated in different age groups (<65 vs > or =65). Age trends in TSH, FT4, and FT3 were examined in euthyroid participants. The cross-sectional association between thyroid dysfunction and MMSE score was evaluated adjusting for confounders. Subclinical hypothyroidism and subclinical hyperthyroidism were more prevalent in older than in younger participants (subclinical hypothyroidism, 3.5% vs 0.4%, P<.03; subclinical hyperthyroidism, 7.8% vs 1.9%, P<.002). In euthyroid participants, TSH and FT3 declined with age, whereas FT4 increased. Older participants with subclinical hyperthyroidism had lower MMSE scores than euthyroid subjects (22.61+/-6.88 vs 24.72+/-4.52, P<.03). In adjusted analyses, participants with subclinical hyperthyroidism were significantly more likely to have cognitive dysfunction (hazard rate=2.26, P=.003). Subtle age-related changes in FT3, FT4, and TSH occur in individuals who remain euthyroid. Subclinical hyperthyroidism is the most prevalent thyroid dysfunction in Italian older persons and is associated with cognitive impairment.

A post-publication analysis of the idealized upper reference value of 2.5 mIU/L for TSH: Time to support the thyroid axis with magnesium and iron especially in the setting of reproduction medicine.

PubMed

Moncayo, Roy; Moncayo, Helga

2017-06-01

Laboratory medicine approaches the evaluation of thyroid function mostly through the single determination of the blood level of thyroid stimulating hormone (TSH). Some authors have suggested an upper reference value for TSH of 2.5 mIU/L. This suggestion has not been confirmed by recent clinical studies. These studies have delivered a clinically valid reference range going from 0.3 to 3.5 mIU/L. These values are valid for both for the general population as well as in the setting of fertility and pregnancy. Current biochemical evidence about the elements required to maintain thyroid function shows that these not only include dietary iodine but also magnesium, iron, selenium and coenzyme Q10. Iron is important for the synthesis of thyroid peroxidase; magnesium-ATP contributes to the active process of iodine uptake; iodine has to be sufficiently present in the diet; selenium acts through selenoproteins to protect the thyroid cell during hormone synthesis and in deiodination of thyroxine; coenzyme Q10 influences thyroid vascularity. As a consequence, good clinical practice requires additional biochemical information on the blood levels of magnesium, selenium, coenzyme Q10 as well as iron status. Since these elements are also important for the maintenance of reproductive function, we postulate that they constitute the connecting link between both endocrine systems.

Reversible changes in brain glucose metabolism following thyroid function normalization in hyperthyroidism.

PubMed

Miao, Q; Zhang, S; Guan, Y H; Ye, H Y; Zhang, Z Y; Zhang, Q Y; Xue, R D; Zeng, M F; Zuo, C T; Li, Y M

2011-01-01

Patients with hyperthyroidism frequently present with regional cerebral metabolic changes, but the consequences of endocrine-induced brain changes after thyroid function normalization are unclear. We hypothesized that the changes of regional cerebral glucose metabolism are related to thyroid hormone levels in patients with hyperthyroid, and some of these changes can be reversed with antithyroid therapy. Relative regional cerebral glucose metabolism was compared between 10 new-onset untreated patients with hyperthyroidism and 20 healthy control participants by using brain FDG-PET scans. Levels of emotional distress were evaluated by using the SAS and SDS. Patients were treated with methimazole. A follow-up PET scan was performed to assess metabolic changes of the brain when thyroid functions normalized. Compared with controls, patients exhibited lower activity in the limbic system, frontal lobes, and temporal lobes before antithyroid treatment. There were positive correlations between scores of depression and regional metabolism in the cingulate and paracentral lobule. The severity of depression and anxiety covaried negatively with pretreatment activity in the inferior temporal and inferior parietal gyri respectively. Compared with the hyperthyroid status, patients with normalized thyroid functions showed an increased metabolism in the left parahippocampal, fusiform, and right superior frontal gyri. The decrease in both FT3 and FT4 was associated with increased activity in the left parahippocampal and right superior frontal gyri. The changes of regional cerebral glucose metabolism are related to thyroid hormone levels in patients with hyperthyroidism, and some cerebral hypometabolism can be improved after antithyroid therapy.

Modulating the function of the immune system by thyroid hormones and thyrotropin.

PubMed

Jara, Evelyn L; Muñoz-Durango, Natalia; Llanos, Carolina; Fardella, Carlos; González, Pablo A; Bueno, Susan M; Kalergis, Alexis M; Riedel, Claudia A

2017-04-01

Accumulating evidence suggests a close bidirectional communication and regulation between the neuroendocrine and immune systems. Thyroid hormones (THs) can exert responses in various immune cells, e.g., monocytes, macrophages, natural killer cells, and lymphocytes, affecting several inflammation-related processes (such as, chemotaxis, phagocytosis, reactive oxygen species generation, and cytokines production). The interactions between the endocrine and immune systems have been shown to contribute to pathophysiological conditions, including sepsis, inflammation, autoimmune diseases and viral infections. Under these conditions, TH therapy could contribute to restoring normal physiological functions. Here we discuss the effects of THs and thyroid stimulating hormone (TSH) on the immune system and the contribution to inflammation and pathogen clearance, as well as the consequences of thyroid pathologies over the function of the immune system. Copyright © 2017 European Federation of Immunological Societies. Published by Elsevier B.V. All rights reserved.

Transposon mutagenesis identifies chromatin modifiers cooperating with Ras in thyroid tumorigenesis and detects ATXN7 as a cancer gene.

PubMed

Montero-Conde, Cristina; Leandro-Garcia, Luis J; Chen, Xu; Oler, Gisele; Ruiz-Llorente, Sergio; Ryder, Mabel; Landa, Iñigo; Sanchez-Vega, Francisco; La, Konnor; Ghossein, Ronald A; Bajorin, Dean F; Knauf, Jeffrey A; Riordan, Jesse D; Dupuy, Adam J; Fagin, James A

2017-06-20

Oncogenic RAS mutations are present in 15-30% of thyroid carcinomas. Endogenous expression of mutant Ras is insufficient to initiate thyroid tumorigenesis in murine models, indicating that additional genetic alterations are required. We used Sleeping Beauty (SB) transposon mutagenesis to identify events that cooperate with Hras G12V in thyroid tumor development. Random genomic integration of SB transposons primarily generated loss-of-function events that significantly increased thyroid tumor penetrance in Tpo-Cre/homozygous FR-Hras G12V mice. The thyroid tumors closely phenocopied the histological features of human RAS-driven, poorly differentiated thyroid cancers. Characterization of transposon insertion sites in the SB-induced tumors identified 45 recurrently mutated candidate cancer genes. These mutation profiles were remarkably concordant with mutated cancer genes identified in a large series of human poorly differentiated and anaplastic thyroid cancers screened by next-generation sequencing using the MSK-IMPACT panel of cancer genes, which we modified to include all SB candidates. The disrupted genes primarily clustered in chromatin remodeling functional nodes and in the PI3K pathway. ATXN7 , a component of a multiprotein complex with histone acetylase activity, scored as a significant SB hit. It was recurrently mutated in advanced human cancers and significantly co-occurred with RAS or NF1 mutations. Expression of ATXN7 mutants cooperated with oncogenic RAS to induce thyroid cell proliferation, pointing to ATXN7 as a previously unrecognized cancer gene.

Transposon mutagenesis identifies chromatin modifiers cooperating with Ras in thyroid tumorigenesis and detects ATXN7 as a cancer gene

PubMed Central

Montero-Conde, Cristina; Leandro-Garcia, Luis J.; Chen, Xu; Oler, Gisele; Ruiz-Llorente, Sergio; Ryder, Mabel; Landa, Iñigo; Sanchez-Vega, Francisco; La, Konnor; Ghossein, Ronald A.; Bajorin, Dean F.; Knauf, Jeffrey A.; Riordan, Jesse D.; Dupuy, Adam J.; Fagin, James A.

2017-01-01

Oncogenic RAS mutations are present in 15–30% of thyroid carcinomas. Endogenous expression of mutant Ras is insufficient to initiate thyroid tumorigenesis in murine models, indicating that additional genetic alterations are required. We used Sleeping Beauty (SB) transposon mutagenesis to identify events that cooperate with HrasG12V in thyroid tumor development. Random genomic integration of SB transposons primarily generated loss-of-function events that significantly increased thyroid tumor penetrance in Tpo-Cre/homozygous FR-HrasG12V mice. The thyroid tumors closely phenocopied the histological features of human RAS-driven, poorly differentiated thyroid cancers. Characterization of transposon insertion sites in the SB-induced tumors identified 45 recurrently mutated candidate cancer genes. These mutation profiles were remarkably concordant with mutated cancer genes identified in a large series of human poorly differentiated and anaplastic thyroid cancers screened by next-generation sequencing using the MSK-IMPACT panel of cancer genes, which we modified to include all SB candidates. The disrupted genes primarily clustered in chromatin remodeling functional nodes and in the PI3K pathway. ATXN7, a component of a multiprotein complex with histone acetylase activity, scored as a significant SB hit. It was recurrently mutated in advanced human cancers and significantly co-occurred with RAS or NF1 mutations. Expression of ATXN7 mutants cooperated with oncogenic RAS to induce thyroid cell proliferation, pointing to ATXN7 as a previously unrecognized cancer gene. PMID:28584132

Frequency of subclinical thyroid dysfunction and risk factors for cardiovascular disease among women at a workplace.

PubMed

Diaz-Olmos, Rodrigo; Nogueira, Antônio-Carlos; Penalva, Daniele Queirós Fucciolo; Lotufo, Paulo Andrade; Benseñor, Isabela Martins

2010-01-01

Subclinical thyroid dysfunction is very common in clinical practice and there is some evidence that it may be associated with cardiovascular disease. The aim here was to evaluate the frequencies of subclinical thyroid disease and risk factors for cardiovascular disease among women at a workplace, and to evaluate the association between subclinical thyroid disease and cardiovascular risk factors among them. Cross-sectional study on 314 women aged 40 years or over who were working at Universidade de São Paulo (USP). All the women answered a questionnaire on sociodemographic characteristics and risk factors for cardiovascular disease and the Rose angina questionnaire. Anthropometric variables were measured and blood samples were analyzed for blood glucose, total cholesterol and fractions, high-sensitivity C-reactive protein, thyroid-stimulating hormone (TSH), free thyroxine (free-T4) and anti-thyroperoxidase antibodies (anti-TPO). The frequencies of subclinical hypothyroidism and hyperthyroidism were, respectively, 7.3% and 5.1%. Women with subclinical thyroid disease presented higher levels of anti-TPO than did women with normal thyroid function (P = 0.01). There were no differences in sociodemographic factors and cardiovascular risk factors according to thyroid function status, except for greater sedentarism among the women with subclinical hypothyroidism. Restricting the comparison to women with subclinical hypothyroidism (TSH > 10 mIU/l) did not change the results. In this sample of women, there was no association between poor profile of cardiovascular risk factors and presence of subclinical thyroid disease that would justify screening at the workplace.

Promise and pitfalls of molecular markers of thyroid nodules

PubMed Central

Jadhav, S.; Lila, Anurag; Bandgar, Tushar; Shah, Nalini

2012-01-01

Thyroid nodules are common in the general population with a prevalence of 5-7% The initial evaluation of thyroid nodules commonly involves thyroid function tests, an ultrasound (USG) and fine needle aspiration biopsy (FNAB). The optimal management of patients with thyroid nodules with indeterminate cytology is plagued by the lack of highly sensitive and specific diagnostic modalities In this article we attempt to review the available literature on the molecular markers which are increasingly being studied for their diagnostic utility in assessing thyroid nodules. The various molecular markers consist of gene mutations, gene re arrangements, RNA based assays and immunohistochemical markers. The molecular markers definitely would help to optimise the management of such patients. PMID:23565369

Diagnosis and management of congenital hypothyroidism.

PubMed

Harrell, G B; Murray, P D

1998-03-01

Thyroid hormones are integral to the development and maturation of the central nervous system as well as normal growth and development. Comprehensive knowledge of the maturation and function of the thyroid gland is essential to understanding the pathophysiology of thyroid dysfunction. Early diagnosis and appropriate treatment in thyroid disease are imperative for normalization of thyroid hormone ratios. Optimal management includes early introduction and strict adherence to a regimen of L-thyroxine and routine monitoring of thyroid levels throughout life. Parents need to understand the importance of consistent medication administration and daily assessment of well-being because these actions are crucial to the attainment of an optimal level of development for infants with congenital hypothyroidism.

Impact of Low-Level Thyroid Hormone Disruption Induced by Propylthiouracil on Brain Development and Function.*

EPA Science Inventory

The critical role of thyroid hormone (TH) in brain development is well established, severe deficiencies leading to significant neurological dysfunction. Much less information is available on more modest perturbations of TH on brain function. The present study induced varying degr...

Marginal Iodide Deficiency and Thyroid Function: Dose-response analysis for quantitative pharmacokinetic modeling

EPA Science Inventory

Severe iodine deficiency is known to cause adverse health outcomes and remains a benchmark for understanding the effects of hypothyroidism. However, the implications of marginal iodine deficiency on function of the thyroid axis remain less well known. The current study examined t...

Search for relevant indications for selenium supplementation in thyroid diseases.

PubMed

Wojciechowska-Durczynska, Katarzyna; Lewinski, Andrzej

2017-08-01

Selenium plays a significant role in the thyroid function and its deficiency is considered by some authors to be a cause of thyroid disorders. The potential therapeutic influence of selenium supplementation in thyroid disease was investigated in several studies and some results were encouraging, however results were inconsistent and did not allow conclusion to be drawn. For that reason, we have performed a review study on relevance of selenium supplementation in thyroid disease. Till now, there is no strong evidence that selenium supplementation leads to clinical improvement in the course of autoimmune thyroiditis, nodular goitre or thyroid cancer. On the other hand, there is some evidence that selenium is effective in the treatment of orbitopathy; thus, the European Group on Graves' Orbitopathy (EUGOGO) recommends selenium administration in mild active orbitopathy.

Mutationally activated BRAF(V600E) elicits papillary thyroid cancer in the adult mouse.

PubMed

Charles, Roch-Philippe; Iezza, Gioia; Amendola, Elena; Dankort, David; McMahon, Martin

2011-06-01

Mutated BRAF is detected in approximately 45% of papillary thyroid carcinomas (PTC). To model PTC, we bred mice with adult-onset, thyrocyte-specific expression of BRAF(V600E). One month following BRAF(V600E) expression, mice displayed increased thyroid size, widespread alterations in thyroid architecture, and dramatic hypothyroidism. Over 1 year, without any deliberate manipulation of tumor suppressor genes, all mice developed PTC displaying nuclear atypia and marker expression characteristic of the human disease. Pharmacologic inhibition of MEK1/2 led to decreased thyroid size, restoration of thyroid form and function, and inhibition of tumorigenesis. Mice with BRAF(V600E)-induced PTC will provide an excellent system to study thyroid tumor initiation and progression and the evaluation of inhibitors of oncogenic BRAF signaling.

Characterization of thyroid function and antithyroid antibody tests among Saudis

PubMed Central

Jammah, Anwar A.; Alshehri, Anwar S.; Alrakhis, Afaf A.; Alhedaithy, Asma S.; Almadhi, Asma M.; Alkwai, Hala M.; Alhamad, Maram M.; Alzahrani, Saad H.

2015-01-01

Objective: To determine the reference intervals for thyroid function tests and the prevalence of thyroid autoimmunity in the Saudi population. Methods: A cross-sectional prospective study was conducted in King Khalid University Hospital, Riyadh, Saudi Arabia from January to June 2013. History and physical examination were obtained. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were measured by Electro-chemiluminescence Immunoassay system-assay. Anti-thyroperoxidase, and anti-thyroglobulin antibodies were measured using enzyme-linked immunosorbent-assay. Subjects with previous or a family history of thyroid disorders, those taking medications affecting thyroid function, pregnant or lactating women, and those with goiter were excluded. Individuals with positive antibodies were excluded from the final analysis of the TSH reference range, but were used to determine the prevalence of thyroid autoimmunity. Results: Out of 337 Saudi subjects initially screened, 132 (aged 13-60 years) were candidates for reference calculation, the mean±standard deviation, and (2.5th-97.5th) percentile of TSH (mIU/L) was 1.96±0.9 (0.59-4.37), for FT4 (pmol/L) was 15.47±1.83 (12.04-19.13), and for FT3 (pmol/L) was 5.22±0.7 (4.07-6.76). The TSH was higher in the antibodies positive group (2.5±1.17 mIU/L) compared with the negative one (1.96±0.9 mIU/L) (p<0.05). Finally, 26% of subjects were tested positive for antithyroid antibodies. Conclusion: The TSH reference range was similar to laboratory references. Thyroid antibodies were prevalent in Saudis, necessitating further work in larger scale studies. PMID:25987111

Characterization of thyroid function and antithyroid antibody tests among Saudis.

PubMed

Jammah, Anwar A; Alshehri, Anwar S; Alrakhis, Afaf A; Alhedaithy, Asma S; Almadhi, Asma M; Alkwai, Hala M; Alhamad, Maram M; Alzahrani, Saad H

2015-06-01

To determine the reference intervals for thyroid function tests and the prevalence of thyroid autoimmunity in the Saudi population.   A cross-sectional prospective study was conducted in King Khalid University Hospital, Riyadh, Saudi Arabia from January to June 2013. History and physical examination were obtained. Thyroid-stimulating hormone (TSH), free thyroxine (FT4), and free triiodothyronine (FT3) were measured by Electro-chemiluminescence Immunoassay system-assay. Anti-thyroperoxidase, and anti-thyroglobulin antibodies were measured using enzyme-linked immunosorbent-assay. Subjects with previous or a family history of thyroid disorders, those taking medications affecting thyroid function, pregnant or lactating women, and those with goiter were excluded. Individuals with positive antibodies were excluded from the final analysis of the TSH reference range, but were used to determine the prevalence of thyroid autoimmunity.   Out of 337 Saudi subjects initially screened, 132 (aged 13-60 years) were candidates for reference calculation, the mean±standard deviation, and (2.5th-97.5th) percentile of TSH (mIU/L) was 1.96±0.9 (0.59-4.37), for FT4 (pmol/L) was 15.47±1.83 (12.04-19.13), and for FT3 (pmol/L) was 5.22±0.7 (4.07-6.76). The TSH was higher in the antibodies positive group (2.5±1.17 mIU/L) compared with the negative one (1.96±0.9 mIU/L) (p less than 0.05). Finally, 26% of subjects were tested positive for antithyroid antibodies.   The TSH reference range was similar to laboratory references. Thyroid antibodies were prevalent in Saudis, necessitating further work in larger scale studies.

Five-year change in morphological and functional alterations of the thyroid gland: the Study of Health in Pomerania.

PubMed

Völzke, Henry; Ittermann, Till; Albers, Martin; Friedrich, Nele; Nauck, Matthias; Below, Harald; Kramer, Axel

2012-07-01

While cross-sectional data on thyroid epidemiology are common, few longitudinal data on the incidence and progression of thyroid disorders exist. The aim of this study was to analyze the 5-year change and the incidence of morphological and functional alterations of the thyroid gland in a previously iodine-deficient area. We used 5-year follow-up data based on 2941 participants (20-79 years) of the population-based Study of Health in Pomerania. The thyroid structure and size were measured by ultrasonography. Thyroid function and serum autoantibodies to thyroperoxidase (anti-TPO-Ab) were evaluated. During follow-up, the median iodine/creatinine ratio decreased slightly from 134.2 to 130.4 μg/g. The mean thyroid volume was nonsignificantly increased by 0.73 mL [confidence interval (CI) -1.68-3.41 mL]. The incidence rate of goiter was 34.0 [CI 30.7-37.7] per 1000 person-years (py), the incident rate of nodules was 16.6 [CI 14.5-19.1] per 1000 py. Median serum thyrotropin levels increased slightly (0.10 [CI -0.10-0.34 mIU/L]). The incidence of positive anti-TPO-Ab was 3.4 [CI 2.6-4.7] per 1000 py. For all thyroid parameters, the regression rates were higher than the incidence rates. After iodine fortification became effective in this previously iodine-deficient region, there is a negative net balance between occurring and reverting goiter and nodules. Along with balanced incidences of hyper- and hypothyroid dysfunction and the low incidence of autoimmune-related findings, these findings indicate that the current iodine status is sufficient to prevent iodine deficiency-related disorders in the adult population of the study region.

Relationship between vitamin A deficiency and the thyroid axis in clinically stable patients with liver cirrhosis related to hepatitis C virus.

PubMed

El-Eshmawy, Mervat M; Arafa, Mona M; Elzehery, Rasha R; Elhelaly, Rania M; Elrakhawy, Mohamed M; El-Baiomy, Azza A

2016-09-01

Vitamin A deficiency (VAD) and altered thyroid function are commonly encountered in patients with liver cirrhosis. The link between vitamin A metabolism and thyroid function has been previously identified. The aim of this study was to explore the association between VAD and the thyroid axis in clinically stable patients with cirrhosis related to hepatitis C virus (HCV). One hundred and twelve patients with clinically stable HCV-related cirrhosis and 56 healthy controls matched for age, sex, and socioeconomic status were recruited for this study. Vitamin A status, liver function, thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), reverse triiodothyronine (rT3), anti-thyroid peroxidase antibodies (anti-TPO), and thyroid volume were evaluated. The prevalence of VAD among patients with HCV-related cirrhosis was 62.5% compared with 5.4% among controls (P < 0.001). Patients with HCV-related cirrhosis had significantly higher FT4, FT3, TSH, and thyroid volume than did healthy controls. Of the 112 patients initially recruited, 18 were excluded (patients with subclinical hypothyroidism and/or anti-TPO positive), so a total of 94 patients with HCV-related cirrhosis were divided into 2 groups according to vitamin A status: VAD and normal vitamin A. Patients with VAD had significantly lower vitamin A intake and serum albumin and higher serum bilirubin, FT4, FT3, and TSH than patients with normal vitamin A status. Multiple logistic regression analysis revealed that VAD was associated with Child-Pugh score (β = 0.11, P = 0.05) and TSH (β = -1.63, P = 0.02) independently of confounding variables. We conclude that VAD may be linked to central hyperthyroidism in patients with clinically stable HCV-related liver cirrhosis.

Thyroid transcriptome analysis reveals different adaptive responses to cold environmental conditions between two chicken breeds

PubMed Central

Yang, Xukai; Wang, Dehe; Zhu, Feng; Yang, Ning; Hou, Zhuocheng; Ning, Zhonghua

2018-01-01

Selection for cold tolerance in chickens is important for improving production performance and animal welfare. The identification of chicken breeds with higher cold tolerance and production performance will help to target candidates for the selection. The thyroid gland plays important roles in thermal adaptation, and its function is influenced by breed differences and transcriptional plasticity, both of which remain largely unknown in the chicken thyroid transcriptome. In this study, we subjected Bashang Long-tail (BS) and Rhode Island Red (RIR) chickens to either cold or warm environments for 21 weeks and investigated egg production performance, body weight changes, serum thyroid hormone concentrations, and thyroid gland transcriptome profiles. RIR chickens had higher egg production than BS chickens under warm conditions, but BS chickens produced more eggs than RIRs under cold conditions. Furthermore, BS chickens showed stable body weight gain under cold conditions while RIRs did not. These results suggested that BS breed is a preferable candidate for cold-tolerance selection and that the cold adaptability of RIRs should be improved in the future. BS chickens had higher serum thyroid hormone concentrations than RIRs under both environments. RNA-Seq generated 344.3 million paired-end reads from 16 sequencing libraries, and about 90% of the processed reads were concordantly mapped to the chicken reference genome. Differential expression analysis identified 46–1,211 genes in the respective comparisons. With regard to breed differences in the thyroid transcriptome, BS chickens showed higher cell replication and development, and immune response-related activity, while RIR chickens showed higher carbohydrate and protein metabolism activity. The cold environment reduced breed differences in the thyroid transcriptome compared with the warm environment. Transcriptional plasticity analysis revealed different adaptive responses in BS and RIR chickens to cope with the cold, and showed higher responsiveness in BS compared with RIR chickens, suggesting greater adaptability of the thyroid in BS chickens. Moreover, 10,053 differential splicing events were revealed among the groups, with RNA splicing and processing, gene expression, transport, and metabolism being the main affected biological processes, identifying a valuable alternative splicing repertoire for the chicken thyroid. A short isoform of TPO (encoding thyroid peroxidase) containing multiple open reading frames was generated in both breeds by skipping exons 4 and 5 in the cold environment. These findings provide novel clues for future studies of the molecular mechanisms underlying cold adaptation and/or acclimation in chickens. PMID:29320582

Thyroid transcriptome analysis reveals different adaptive responses to cold environmental conditions between two chicken breeds.

PubMed

Xie, Shanshan; Yang, Xukai; Wang, Dehe; Zhu, Feng; Yang, Ning; Hou, Zhuocheng; Ning, Zhonghua

2018-01-01

Selection for cold tolerance in chickens is important for improving production performance and animal welfare. The identification of chicken breeds with higher cold tolerance and production performance will help to target candidates for the selection. The thyroid gland plays important roles in thermal adaptation, and its function is influenced by breed differences and transcriptional plasticity, both of which remain largely unknown in the chicken thyroid transcriptome. In this study, we subjected Bashang Long-tail (BS) and Rhode Island Red (RIR) chickens to either cold or warm environments for 21 weeks and investigated egg production performance, body weight changes, serum thyroid hormone concentrations, and thyroid gland transcriptome profiles. RIR chickens had higher egg production than BS chickens under warm conditions, but BS chickens produced more eggs than RIRs under cold conditions. Furthermore, BS chickens showed stable body weight gain under cold conditions while RIRs did not. These results suggested that BS breed is a preferable candidate for cold-tolerance selection and that the cold adaptability of RIRs should be improved in the future. BS chickens had higher serum thyroid hormone concentrations than RIRs under both environments. RNA-Seq generated 344.3 million paired-end reads from 16 sequencing libraries, and about 90% of the processed reads were concordantly mapped to the chicken reference genome. Differential expression analysis identified 46-1,211 genes in the respective comparisons. With regard to breed differences in the thyroid transcriptome, BS chickens showed higher cell replication and development, and immune response-related activity, while RIR chickens showed higher carbohydrate and protein metabolism activity. The cold environment reduced breed differences in the thyroid transcriptome compared with the warm environment. Transcriptional plasticity analysis revealed different adaptive responses in BS and RIR chickens to cope with the cold, and showed higher responsiveness in BS compared with RIR chickens, suggesting greater adaptability of the thyroid in BS chickens. Moreover, 10,053 differential splicing events were revealed among the groups, with RNA splicing and processing, gene expression, transport, and metabolism being the main affected biological processes, identifying a valuable alternative splicing repertoire for the chicken thyroid. A short isoform of TPO (encoding thyroid peroxidase) containing multiple open reading frames was generated in both breeds by skipping exons 4 and 5 in the cold environment. These findings provide novel clues for future studies of the molecular mechanisms underlying cold adaptation and/or acclimation in chickens.

The Emerging Cell Biology of Thyroid Stem Cells

PubMed Central

Latif, Rauf; Minsky, Noga C.; Ma, Risheng

2011-01-01

Context: Stem cells are undifferentiated cells with the property of self-renewal and give rise to highly specialized cells under appropriate local conditions. The use of stem cells in regenerative medicine holds great promise for the treatment of many diseases, including those of the thyroid gland. Evidence Acquisition: This review focuses on the progress that has been made in thyroid stem cell research including an overview of cellular and molecular events (most of which were drawn from the period 1990–2011) and discusses the remaining problems encountered in their differentiation. Evidence Synthesis: Protocols for the in vitro differentiation of embryonic stem cells, based on normal developmental processes, have generated thyroid-like cells but without full thyrocyte function. However, agents have been identified, including activin A, insulin, and IGF-I, which are able to stimulate the generation of thyroid-like cells in vitro. In addition, thyroid stem/progenitor cells have been identified within the normal thyroid gland and within thyroid cancers. Conclusions: Advances in thyroid stem cell biology are providing not only insight into thyroid development but may offer therapeutic potential in thyroid cancer and future thyroid cell replacement therapy. PMID:21778219

APPLICATION OF ORGANIC IODINE SPECIES ANALYTICS: DETERMINING THYROID HORMONE STATUS IN ADULT DANIO RERIO AND DEVELOPING XENOPUS LAEVIS USING LC/ICP-MS

EPA Science Inventory

Disruption of normal thyroid function by xenobiotic chemicals is an important ecological issue. Theoretically, normal thyroid hormone (TH) homeostasis and action can be disrupted at several sites in the synthetic and elimination pathways. Indeed, xenobiotic chemicals, which are k...

Identification of Coordinately Regulated Functional Modules in Thyroid Tissues from Rats Exposed to a Tumorigenic and a Non-Tumorigenic Conazole Fungicide Using Oncomine®

EPA Science Inventory

Conazoles are triazole- or imidazole-containing fungicides used in agriculture and medicine. Using transcriptomic analysis of rat thyroid tissues exposed to either tumorigenic or non-tumorigenic structurally related conazoles, we identified new findings on thyroid gene expressio...

Hyperthyroidism and the Heart.

PubMed

Osuna, Patricia Mejia; Udovcic, Maja; Sharma, Morali D

2017-01-01

Thyroid hormones have a significant impact on cardiac function and structure. Excess thyroid hormone affects cardiovascular hemodynamics, leading to high-output heart failure and, in late stages, dilated cardiomyopathy. In this review, we discuss how hyperthyroidism affects cardiovascular pathophysiology and molecular mechanisms and examine the complications caused by excess thyroid hormone, such as heart failure and atrial fibrillation.

Prospective role of ascorbic acid (vitamin C) in attenuating hexavalent chromium-induced functional and cellular damage in rat thyroid.

PubMed

Qureshi, Irfan Zia; Mahmood, Tariq

2010-07-01

Occupational exposure to toxic heavy metals may render industrial workers with thyroid-related problems. Here, we examined the role of ascorbic acid (vitamin C) against hexavalent chromium Cr (VI)-induced damage in rat thyroid gland. Potassium dichromate (K2Cr2O7) and ascorbic acid doses were 60 microg and 120 mg kg(-1) body wt (intraperitoneally [i.p.]) respectively. Treatment regimens were group I rats, saline treated control; group II, only K2Cr2O7; group III, ascorbic acid 1 hour prior K2Cr2O7; group IV, simultaneous doses of ascorbic acid and K2Cr2O7, and group V, a combined premix dose of ascorbic acid and K2 Cr2O7 (2:1 ratio). Blood samples were taken before dosing the animals and 48 hours post exposure to determine the serum thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) concentrations. Toward end of experiment, rats were sacrificed and thyroid glands were processed to evaluate the extent of cellular insult. Results showed significantly increased TSH and decreased FT3 and FT4 concentrations in groups II, III and IV rats as compared to control levels (p < 0.05). In contrast, in group V rats, serum TSH, FT3 and FT4 concentrations neared control concentrations. Histopathologically, protective effect of ascorbic acid was found in group V rats only, where thyroid gland structure neared control thyroid except the follicular size that was decreased (p < 0.05). Follicular density was no different from control. Basal laminae were intact, interfollicular spaces were normal. Colloid retraction and/or reabsorption were reduced maximally. Epithelial cell height was no different from control; epithelial follicular index increased only 1.3 fold, whereas nuclear-cytoplasmic (N/C) ratio was decreased by 14% only. The study indicates that the ascorbic acid may have the potential to protect thyroid gland from chromium toxicity; however, the study warrants further in-depth experimentation to precisely elucidate this role.

Vitamin D 1alpha-hydroxylase (CYP1alpha) polymorphism in Graves' disease, Hashimoto's thyroiditis and type 1 diabetes mellitus.

PubMed

Pani, Michael A; Regulla, Karoline; Segni, Maria; Krause, Maren; Hofmann, Stefan; Hufner, Michael; Herwig, Jurgen; Pasquino, Anna Maria; Usadel, Klaus-H; Badenhoop, Klaus

2002-06-01

The vitamin D endocrine system plays a role in the regulation of (auto)immunity and cell proliferation. Vitamin D 1alpha-hydroxylase (CYP1alpha) is one of the key enzymes regulating both systemic and tissue levels of 1,25-dihyroxyvitamin D(3) (1,25(OH)(2)D(3)). Administration of 1,25(OH)(2)D(3), whose serum levels were found to be reduced in type 1 diabetes and thyroid autoimmunity, prevents these diseases in animal models. We therefore investigated a recently reported CYP1alpha polymorphism for an association with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. Four hundred and seven Caucasian pedigrees with one offspring affected by either type 1 diabetes (209 families), Graves' disease (92 families) or Hashimoto's thyroiditis (106 families) were genotyped for a C/T polymorphism in intron 6 of the CYP1alpha gene on chromosome 12q13.1-13.3 and transmission disequilibrium testing (TDT) was performed. Subsets of affected offspring stratified for HLA-DQ haplotype were compared using chi(2) testing. There was no deviation from the expected transmission frequency in either type 1 diabetes mellitus (P=0.825), Graves' disease (P=0.909) or Hashimoto's thyroiditis (P=0.204). However, in Hashimoto's thyroiditis the CYP1alpha C allele was significantly more often transmitted to HLA-DQ2(-) patients (27 transmitted vs 14 not transmitted; TDT: P=0.042) than expected. The C allele was less often transmitted to HLA-DQ2(+) patients (9 transmitted vs 12 not transmitted; TDT: P=0.513), although the difference was not significant (chi(2) test: P=0.143). A similar difference was observed in type 1 diabetes between offspring with high and low risk HLA-DQ haplotypes (chi(2) test: P=0.095). The CYP1alpha intron 6 polymorphism appears not to be associated with type 1 diabetes mellitus, Graves' disease and Hashimoto's thyroiditis. A potential association in subsets of patients with type 1 diabetes and Hashimoto's thyroiditis should be further investigated as well as its functional implications.

Hyperfunctioning Solid/Trabecular Follicular Carcinoma of the Thyroid Gland

PubMed Central

Giovanella, Luca; Fasolini, Fabrizio; Suriano, Sergio; Mazzucchelli, Luca

2010-01-01

A 68-year-old woman with solid/trabecular follicular thyroid carcinoma inside of an autonomously functioning thyroid nodule is described in this paper. The patient was referred to our clinic for swelling of the neck and an increased pulse rate. Ultrasonography showed a slightly hypoechoic nodule in the right lobe of the thyroid. Despite suppressed TSH levels, the 99mTc-pertechnetate scan showed a hot area corresponding to the nodule with a suppressed uptake in the remaining thyroid tissue. Histopathological examination of the nodule revealed a solid/trabecular follicular thyroid carcinoma. To the best of our knowledge, this is the first case of hyperfunctioning follicular solid/trabecular carcinoma reported in the literature. Even if a hyperfunctioning thyroid carcinoma is an extremely rare malignancy, careful management is recommended so that a malignancy will not be overlooked in the hot thyroid nodules. PMID:20847957

Thyroid hormone action on intermediary metabolism. Part I: respiration, thermogenesis and carbohydrate metabolism.

PubMed

Müller, M J; Seitz, H J

1984-01-02

The effect of thyroid hormones on mitochondrial respiration are summarized: T3 directly stimulates mitochondrial respiration and the synthesis of adenosine 5'-triphosphate (ATP). Cytosolic ATP availability is increased by a thyroid hormone-induced increase in adenine nucleotide translocation across the mitochondrial membrane; the steady state ATP concentration and the cytosolic ATP/adenosine 5'-diphosphate (ADP) ratio is even decreased in hyperthyroid tissues because of the simultaneous stimulation of the synthesis and consumption of ATP. With regard to the thyroid hormone-induced energy wasting processes, heart work, intra- and interorgan futile cycling and Na+/K+-ATPase are involved to varying degrees. As a consequence of the thyroid hormone-induced hydrolysis of ATP, thermogenesis is increased in hyper- and decreased in hypothyroidism. Despite an increased rate of glucose utilization, clinical and experimental hyperthyroidism is often characterized by an abnormal oral glucose tolerance test. This finding is due to the thyroid hormone-induced increase in intestinal glucose absorption as well as the still enhanced endogenous glucose production in the liver. Hypothyroid patients show a reduced glucose tolerance test because of a decrease in intestinal glucose absorption and a sometimes reduced glucose turnover. The thyroid hormone-induced alterations in glucose metabolism are most probably not due to alterations in serum insulin levels and/or to a peripheral insulin resistance at the receptor level.

Ventricular Fibrillation Associated With Dynamic Changes in J-Point Elevation in a Patient With Silent Thyroiditis.

PubMed

Karashima, Shigehiro; Tsuda, Toyonobu; Wakabayashi, Yusuke; Kometani, Mitsuhiro; Demura, Masashi; Ichise, Taro; Kawashiri, Masa-Aki; Takeda, Yoshiyu; Hayashi, Kenshi; Yoneda, Takashi

2018-02-01

A J wave is a common electrocardiographic finding in the general population. Individuals with prominent J waves in multiple electrocardiogram (ECG) leads have a higher risk of lethal arrhythmias than those with low-amplitude J waves. There are few reports about the relationship between thyroid function and J-wave amplitude. We report the case of a 45-year-old man who had unexpected ventricular fibrillation (VF). He had dynamic J-point elevation in multiple ECG leads. Possible early repolarization syndrome was diagnosed. He also had thyrotoxicosis caused by silent thyroiditis, and his J-wave amplitude decreased according to changes in thyroid function because of spontaneous remission of silent thyroiditis. There was a positive correlation between serum triiodothyronine levels and J-wave amplitudes. The findings in case suggested silent thyroiditis may contribute to the occurrence of VF in a patient with dynamic changes in J-point elevation in multiple ECG leads. Thyrotoxicosis is a relatively common endocrine disease; therefore, clinicians should pay attention to J-wave amplitude in the ECG of patients with thyrotoxicosis.

Corticotropin-releasing hormone: Mediator of vertebrate life stage transitions?

PubMed

Watanabe, Yugo; Grommen, Sylvia V H; De Groef, Bert

2016-03-01

Hormones, particularly thyroid hormones and corticosteroids, play critical roles in vertebrate life stage transitions such as amphibian metamorphosis, hatching in precocial birds, and smoltification in salmonids. Since they synergistically regulate several metabolic and developmental processes that accompany vertebrate life stage transitions, the existence of extensive cross-communication between the adrenal/interrenal and thyroidal axes is not surprising. Synergies of corticosteroids and thyroid hormones are based on effects at the level of tissue hormone sensitivity and gene regulation. In addition, in representative nonmammalian vertebrates, corticotropin-releasing hormone (CRH) stimulates hypophyseal thyrotropin secretion, and thus functions as a common regulator of both the adrenal/interrenal and thyroidal axes to release corticosteroids and thyroid hormones. The dual function of CRH has been speculated to control or affect the timing of vertebrate life history transitions across taxa. After a brief overview of recent insights in the molecular mechanisms behind the synergic actions of thyroid hormones and corticosteroids during life stage transitions, this review examines the evidence for a possible role of CRH in controlling vertebrate life stage transitions. Copyright © 2016 Elsevier Inc. All rights reserved.

[Effect of space flight aboard "Kosmos-1129" on thyroid hormone content of the blood and thyroid gland of rats].

PubMed

Tigranian, R A; Kalita, N F; Makho, L; Langer, P; Knopp, Ia

1985-01-01

Thyrotrophin, thyroxine, triiodothyronine, and reverse triiodothyronine were measured in plasma and thyroxine and triiodothyronine in the thyroid gland of the rats flown for 18.5 days onboard Cosmos-1129. Postflight the plasma content of thyrotrophin and triiodothyronine increased and that of thyroxine decreased and the gland content of thyroxine and triiodothyronine diminished. It is postulated that in the flight animals the functional activity of the thyroid gland declined.

Comparison of the therapeutic effects of prednisolone and nonsteroidal anti-inflammatory drugs in patients with subacute thyroiditis.

PubMed

Sato, Junko; Uchida, Toyoyoshi; Komiya, Koji; Goto, Hiromasa; Takeno, Kageumi; Suzuki, Ruriko; Honda, Akira; Himuro, Miwa; Watada, Hirotaka

2017-01-01

Subacute thyroiditis is a transient inflammatory thyroid disease of unknown etiology. The primary goal for treatment is to mitigate inflammation. The aim of this retrospective study was to compare the therapeutic effects of prednisolone and nonsteroidal anti-inflammation drugs in patients with subacute thyroiditis. In this study, 53 consecutive Japanese patients who had been diagnosed with were referred to our hospital for further management. After excluding 11 patients (9 did not need treatment, 2 did not meet the criteria for diagnosis of subacute thyroiditis), the remaining 42 patients were treated either with prednisolone (n = 25) or loxoprofen (n = 17). We compared the time periods required for resolution of clinical symptoms and signs and normalization of thyroid function between the two groups. The mean dose of prednisolone was 15.0 (range, 14-16) mg/day and that of loxoprofen was 180 mg/day. The time period to normalization of thyroid function was comparable between the prednisolone and loxoprofen groups (25, 18-36, vs 32, 21-39 days, p = 0.388). However, the time period for resolution of symptoms was shorter under prednisolone than loxoprofen (7, 7-12 days, vs 21, 14-32 days, p < 0.001). Prednisolone treatment of patients with subacute thyroiditis was superior to nonsteroidal anti-inflammation drugs with regard to resolution of symptoms.

Diagnosis and Management of Subclinical Hypothyroidism in Elderly Adults: A Review of the Literature.

PubMed

Hennessey, James V; Espaillat, Ramon

2015-08-01

The estimated prevalence of subclinical hypothyroidism (SCH) in the general population is 3% to 8%. As the average age of the population in the United States and other countries continues to increase, the overall prevalence of SCH may also be expected to increase. Although age-related changes in thyroid function are well described, normal thyroid-stimulating hormone (TSH) reference limits, derived for age-specific populations, are not routinely used to identify thyroid dysfunction in elderly adults. Therefore, currently accepted values for the upper limit of normal of TSH may be inappropriate for diagnosing SCH in individuals aged 65 and older, resulting in potential overestimation of the prevalence of SCH in this population. This review discusses the current evidence of the effects of SCH on cardiovascular health and neuropsychiatric function in older adults. Although the results of some studies are conflicting, the overall evidence suggests that the consequences of SCH may be different for elderly adults than for younger populations. Treatment of SCH in older individuals requires special consideration with regard to thyroid hormone replacement therapy and expected clinical outcomes. Although careful identification of individuals with persistent SCH who could benefit from levothyroxine treatment is necessary, current evidence suggests that individuals with TSH levels greater than 10 mIU/L who test positive for antithyroid antibodies or are symptomatic may benefit from levothyroxine treatment to reduce the risk of progression to overt hypothyroidism, decrease the risk of adverse cardiovascular events, and improve their quality of life. After treatment is initiated, careful monitoring is essential. © 2015, The Authors. The Journal of the American Geriatrics Society published by Wiley Periodicals, Inc. on behalf of The American Geriatrics Society.

The AQUA-FONTIS study: protocol of a multidisciplinary, cross-sectional and prospective longitudinal study for developing standardized diagnostics and classification of non-thyroidal illness syndrome

PubMed Central

Dietrich, Johannes W; Stachon, Axel; Antic, Biljana; Klein, Harald H; Hering, Steffen

2008-01-01

Background Non-thyroidal illness syndrome (NTIS) is a characteristic functional constellation of thyrotropic feedback control that frequently occurs in critically ill patients. Although this condition is associated with significantly increased morbidity and mortality, there is still controversy on whether NTIS is caused by artefacts, is a form of beneficial adaptation, or is a disorder requiring treatment. Trials investigating substitution therapy of NTIS revealed contradictory results. The comparison of heterogeneous patient cohorts may be the cause for those inconsistencies. Objectives Primary objective of this study is the identification and differentiation of different functional states of thyrotropic feedback control in order to define relevant evaluation criteria for the prognosis of affected patients. Furthermore, we intend to assess the significance of an innovative physiological index approach (SPINA) in differential diagnosis between NTIS and latent (so-called "sub-clinical") thyrotoxicosis. Secondary objective is observation of variables that quantify distinct components of NTIS in the context of independent predictors of evolution, survival or pathophysiological condition and influencing or disturbing factors like medication. Design The approach to a quantitative follow-up of non-thyroidal illness syndrome (AQUA FONTIS study) is designed as both a cross-sectional and prospective longitudinal observation trial in critically ill patients. Patients are observed in at least two evaluation points with consecutive assessments of thyroid status, physiological and clinical data in additional weekly observations up to discharge. A second part of the study investigates the neuropsychological impact of NTIS and medium-term outcomes. The study design incorporates a two-module structure that covers a reduced protocol in form of an observation trial before patients give informed consent. Additional investigations are performed if and after patients agree in participation. Trial Registration ClinicalTrials.gov NCT00591032 PMID:18851740

Prolonged food deprivation increases mRNA expression of deiodinase 1 and 2, and thyroid hormone receptor β-1 in a fasting-adapted mammal

PubMed Central

Martinez, Bridget; Soñanez-Organis, José G.; Vázquez-Medina, José Pablo; Viscarra, Jose A.; MacKenzie, Duncan S.; Crocker, Daniel E.; Ortiz, Rudy M.

2013-01-01

SUMMARY Food deprivation in mammals is typically associated with reduced thyroid hormone (TH) concentrations and deiodinase content and activity to suppress metabolism. However, in prolonged-fasted, metabolically active elephant seal pups, TH levels are maintained, if not elevated. The functional relevance of this apparent paradox is unknown and demonstrates variability in the regulation of TH levels, metabolism and function in food-deprived mammals. To address our hypothesis that cellular TH-mediated activity is upregulated with fasting duration, we quantified the mRNA expression and protein content of adipose and muscle deiodinase type I (DI1) and type II (DI2), and TH receptor beta-1 (THrβ-1) after 1, 3 and 7 weeks of fasting in northern elephant seal pups (N=5–7 per week). Fasting did not decrease the concentrations of plasma thyroid stimulating hormone, total triiodothyronine (tT3), free T3, total thyroxine (tT4) or free T4, suggesting that the hypothalamic–pituitary–thyroid axis is not suppressed, but rather maintained during fasting. Mean mRNA expression of adipose DI1 and DI2 increased threefold and fourfold, respectively, and 20- and 30-fold, respectively, in muscle. With the exception of adipose DI1, protein expression of adipose DI2 and muscle DI1 and DI2 increased twofold to fourfold. Fasting also increased adipose (fivefold) and muscle (fourfold) THrβ-1 mRNA expression, suggesting that the mechanisms mediating cellular TH activity are upregulated with prolonged fasting. The data demonstrate a unique, atypical mechanism of TH activity and regulation in mammals adapted to prolonged food deprivation in which the potential responsiveness of peripheral tissues and cellular TH activity are increased, which may contribute to their lipid-based metabolism. PMID:24307712

Thyroid Stimulating Hormone Receptor Antibodies in Thyroid Eye Disease-Methodology and Clinical Applications.

PubMed

Diana, Tanja; Kahaly, George J

2018-05-02

Thyroid stimulating hormone receptor antibodies (TSHR-Ab) cause autoimmune hyperthyroidism and are prevalent in patients with related thyroid eye disease (TED). To provide a historical perspective on TSHR-Ab and to present evidence-based recommendations for clinical contemporary use. The authors review the recent literature pertaining to TSHR-Ab in patients with TED and describe the various immunoassays currently used for detecting TSHR-Ab and their clinical applications. We provide a historical summary and description of the various methods used to detect TSHR-Ab, foremost, the functional TSHR-Ab. Increasing experimental and clinical data demonstrate the clinical usefulness of cell-based bioassays for measurements of functional TSHR-Ab in the diagnosis and management of patients with autoimmune TED and in the characterization of patients with autoimmune-induced hyperthyroidism and hypothyroidism. Thyroid stimulating hormone receptor antibodies, especially the functional stimulating antibodies, are sensitive, specific, and reproducible biomarkers for patients with autoimmune TED and correlate well with clinical disease activity and clinical severity. Unlike competitive-binding assays, bioassays have the advantage of indicating not only the presence of antibodies but also their functional activity and potency. Measurement of TSHR-Ab (especially stimulating antibodies) is a clinically useful tool for the management of patients with TED.

Thyroid hormone and obesity.

PubMed

Pearce, Elizabeth N

2012-10-01

To review several of the most recent and most important clinical studies regarding the effects of thyroid treatments on weight change, associations between thyroid status and weight, and the effects of obesity and weight change on thyroid function. Weight decreases following treatment for hypothyroidism. However, following levothyroxine treatment for overt hypothyroidism, weight loss appears to be modest and mediated primarily by loss of water weight rather than fat. There is conflicting evidence about the effects of thyroidectomy on weight. In large population studies, even among euthyroid individuals, serum thyroid-stimulating hormone is typically positively associated with body weight and BMI. Both serum thyroid-stimulating hormone and T3 are typically increased in obese compared with lean individuals, an effect likely mediated, at least in part, by leptin. Finally, there is no consistent evidence that thyroid hormone treatment induces weight loss in obese euthyroid individuals, but thyroid hormone analogues may eventually be useful for weight loss. The interrelationships between body weight and thyroid status are complex.

A Review: Radiographic Iodinated Contrast Media-Induced Thyroid Dysfunction

PubMed Central

Leung, Angela M.; Braverman, Lewis E.; Brent, Gregory A.; Pearce, Elizabeth N.

2015-01-01

Context: Thyroid hormone production is dependent on adequate iodine intake. Excess iodine is generally well-tolerated, but thyroid dysfunction can occur in susceptible individuals after excess iodine exposure. Radiological iodinated contrast media represent an increasingly common source of excess iodine. Objective: This review will discuss the thyroidal response after acute exposure to excess iodine; contrast iodine-induced thyroid dysfunction; risks of iodine-induced thyroid dysfunction in vulnerable populations, such as the fetus, neonate, and patients with impaired renal function; and recommendations for the assessment and treatment of contrast iodine-induced thyroid dysfunction. Methods: Data for this review were identified by searching PubMed, Google Scholar, and references from relevant articles from 1948 to 2014. Conclusions: With the increase in the use of computed tomography scans in the United States, there is increasing risk of contrast-induced thyroid dysfunction. Patients at risk of developing iodine-induced thyroid dysfunction should be closely monitored after receiving iodinated contrast media and should be treated as needed. PMID:25375985

ShearWave™ elastography for evaluation of the elasticity of Hashimoto's thyroiditis.

PubMed

Liu, Haifang; Zhu, Yuping; Jiao, Jie; Yuan, Jia; Pu, Tianning; Yong, Qiang

2018-04-13

The aim of this study was to assess the elasticity of Hashimoto's thyroiditis in the different processes via supersonic ShearWave™ Elastography (SWE™). Quantitative information is delivered as Young's modulus value expressed in kilo-Pascal (kPa). 30 healthy female and 30 healthy male individuals aging at 40±20 y had undergone conventional ultrasonography and SWE to determine the influence of gender on elasticity of thyroid. Also 60 female and 60 male patients (mean age, 40±20 y) with Hashimoto's thyroiditis in different processes underwent conventional ultrasonography and SWE to determine the elasticity of thyroid in Hashimoto's thyroiditis. Furthermore, the relationship between elasticity values and thyroid peroxidase antibody (TPOAB) in the patients was investigated. We found significant impact of gender on elasticity values of healthy thyroids. Our study showed that increased elasticity values with statistical significance in hyperthyroidism stage, normal thyroid function stage and hypothyroidism were shown. Low degree relationship between elasticity values and TPOAB was found in 60 male patients. However, there was no such correlation in female patients.

Thyroid Hormones and Moderate Exposure to Perchlorate during Pregnancy in Women in Southern California.

PubMed

Steinmaus, Craig; Pearl, Michelle; Kharrazi, Martin; Blount, Benjamin C; Miller, Mark D; Pearce, Elizabeth N; Valentin-Blasini, Liza; DeLorenze, Gerald; Hoofnagle, Andrew N; Liaw, Jane

2016-06-01

Findings from national surveys suggest that everyone in the United States is exposed to perchlorate. At high doses, perchlorate, thiocyanate, and nitrate inhibit iodide uptake into the thyroid and decrease thyroid hormone production. Small changes in thyroid hormones during pregnancy, including changes within normal reference ranges, have been linked to cognitive function declines in the offspring. We evaluated the potential effects of low environmental exposures to perchlorate on thyroid function. Serum thyroid hormones and anti-thyroid antibodies and urinary perchlorate, thiocyanate, nitrate, and iodide concentrations were measured in 1,880 pregnant women from San Diego County, California, during 2000-2003, a period when much of the area's water supply was contaminated from an industrial plant with perchlorate at levels near the 2007 California regulatory standard of 6 μg/L. Linear regression was used to evaluate associations between urinary perchlorate and serum thyroid hormone concentrations in models adjusted for urinary creatinine and thiocyanate, maternal age and education, ethnicity, and gestational age at serum collection. The median urinary perchlorate concentration was 6.5 μg/L, about two times higher than in the general U.S. Adjusted associations were identified between increasing log10 perchlorate and decreasing total thyroxine (T4) [regression coefficient (β) = -0.70; 95% CI: -1.06, -0.34], decreasing free thyroxine (fT4) (β = -0.053; 95% CI: -0.092, -0.013), and increasing log10 thyroid-stimulating hormone (β = 0.071; 95% CI: 0.008, 0.133). These results suggest that environmental perchlorate exposures may affect thyroid hormone production during pregnancy. This could have implications for public health given widespread perchlorate exposure and the importance of thyroid hormone in fetal neurodevelopment. Steinmaus C, Pearl M, Kharrazi M, Blount BC, Miller MD, Pearce EN, Valentin-Blasini L, DeLorenze G, Hoofnagle AN, Liaw J. 2016. Thyroid hormones and moderate exposure to perchlorate during pregnancy in women in Southern California. Environ Health Perspect 124:861-867; http://dx.doi.org/10.1289/ehp.1409614.

[Maternal autoimmune thyroid disease: relevance for the newborn].

PubMed

Temboury Molina, M Carmen; Rivero Martín, M José; de Juan Ruiz, Jesús; Ares Segura, Susana

2015-04-08

Autoimmune thyroid disease is amongst the most frequent endocrine disorders during pregnancy. It is associated with an increase in perinatal morbidity, congenital defects, neurological damage, fetal and neonatal thyroid dysfunction. Maternal thyroid hormones play a key role in child neurodevelopment. We aimed to evaluate the thyroid function and the clinical course of neonates born from mothers with autoimmune thyroid disease during the first months of life in order to define the follow-up. We monitored thyroid function and clinical status during the first months in 81 newborns of mothers with autoimmune thyroid disease; 16 had Graves disease and 65 autoimmune thyroiditis. A percentage of 4.93 newborns had congenital defects, and 8.64% neonates showed an increase in thyrotropin (TSH) (>9.5 μUI/mL 2 times) and required thyroxin within the first month of life. A 85.7% of these showed a negative newborn screening (due to a later increase of TSH). A higher TSH value in the newborn was related to an older age of the mother, higher levels of thyroid peroxidase (TPO) antibody during pregnancy and lower birth weight. A higher free thyroxine (FT4) value in the newborn was related to fewer days of life and mothers with Graves disease. We recommend the evaluation of TSH, T4 and TPO antibodies before 10 weeks in all pregnant women with follow-up if maternal thyroid autoimmunity or disorders is detected. It is also recommended to test children's serum TSH and FT4 at 48 h of life in newborns of mothers with autoimmune thyroid disease and repeat them between the 2nd and 4th week in children with TSH>6 μUI/mL. Careful endocrine follow-up is advised in pregnant women and children if hyperthyroidism is detected. Copyright © 2013 Elsevier España, S.L.U. All rights reserved.

Thyroid Volume and Its Relation to Anthropometric Measures in a Healthy Cuban Population

PubMed Central

Turcios, Silvia; Lence-Anta, Juan J.; Santana, Jose-Luis; Pereda, Celia M.; Velasco, Milagros; Chappe, Mae; Infante, Idalmis; Bustillo, Marlene; García, Anabel; Clero, Enora; Maillard, Stephane; Rodriguez, Regla; Xhaard, Constance; Ren, Yan; Rubino, Carole; Ortiz, Rosa M.; de Vathaire, Florent

2015-01-01

Objectives The aim of this study was to describe the thyroid volume in healthy adults by ultrasound and to correlate this volume with some anthropometric measures and other differentiated thyroid cancer risk factors. Study Design Thyroid volume and anthropometric measures were recorded in a sample of 100 healthy adults, including 21 men and 79 women aged 18-50 years, living in a non-iodine-deficient area of Havana city. Results The average thyroid volume was 6.6 ± 0.26 ml; it was higher in men (7.3 ml) than in women (6.4 ml; p = 0.15). In the univariate analysis, thyroid volume was correlated with all anthropometric measures, but in the multivariate analysis, body surface area was found to be the only significant anthropometric parameter. Thyroid volume was also higher in current or former smokers and in persons with blood group AB or B. Conclusion Specific reference values of thyroid volume as a function of body surface area could be used for evaluating thyroid volume in clinical practice. The relation between body surface area and thyroid volume is coherent with what is known about the relation of thyroid volume to thyroid cancer risk, but the same is not true about the relation between thyroid volume and smoking habit. PMID:25960963

Estimation of Salivary Parameters among Autoimmune Thyroiditis Patients.

PubMed

Syed, Yasmeen Amthul; Reddy, Bh Satheesh; Ramamurthy, T K; Rajendra, Kavitha; Nerella, Narendra Kumar; Krishnan, Meenakshi; Ramesh, M V; Mohammed, Rezwana Begum

2017-07-01

Saliva is a complex secretion that protects and lubricates the oral cavity. Various systemic diseases and their treatment alter the salivary gland function; one such disease is Autoimmune Thyroid Disease (AITD). AITD has been postulated to exert its hormonal influence on the salivary glands, leading to reduced salivary output. There's a paucity of literature, verifying the stated conjunction in human subjects. The aim was to investigate the salivary profile in AITD patients and its comparison with controls. Descriptive cross-sectional comparative study was conducted using convenience sampling method for screening the presence of thyroid disorders. Two groups comprising of 30 patients in each group diagnosed with autoimmune hypothyroiditis (n=30) and hyperthyroiditis (n=30) respectively and thirty healthy volunteers who were age and sex matched were included as controls. Saliva was collected and evaluated for Unstimulated Salivary Flow Rate (USSFR), pH and buffer capacity. ANOVA and Tukey post-hoc test was performed to find the statistical significance and for pairwise comparison. Statistically significant difference was observed between autoimmune hypothyroiditis, autoimmune hyperthyroiditis and control group with respect to USSFR (p<0.007), pH (p<0.001) and buffer capacity (p<0.001). On pairwise comparisons statistically significant difference was observed between autoimmune hypothyroiditis and autoimmune hyperthyroiditis with respect to controls. We conclude that significant involvement of salivary glands may occur in cases of AITD. Our study showed significant reduction of sialometric values in AITD patients when compared to controls. A strong clinical suspicion of thyroid diseases should be considered when there is chronic hyposalivation; hence thyroid profile must also be done, if the known causes have been excluded.

[Reference interval in preliminary investigation of maternal thyroid function during pregnancy in Shenzhen China].

PubMed

Yu, Lian; Yue, Huakui; Lin, Haoyun; Wu, Wenyuan

2014-11-04

To explore the thyroid function distribution of different trimesters among normal pregnant women and establish the reference interval for maternal thyroid function during pregnancy in Shenzhen, China. A prospective study was conducted for healthy pregnant women in first trimester (n = 334), second trimester (n = 272), third trimester (n = 271) and non-pregnant controls (n = 77) from December 2012 to June 2013 at our hospital. Free triiodothyronine (FT3), free thyroxine (FT4), thyroid stimulating hormone (TSH), triiodothyronine (TT3) and thyroxine (T4) of four groups were measured and analyzed. And the reference intervals for different trimesters were established. TSH declined in the first trimester and then rose in the second trimester. The reference ranges of TSH for early, middle and late pregnancy were 0.08-4.39, 0.41-4.16 and 0.30-5.46 mIU/L respectively. FT4 and healthy control groups showed no significant difference in the first trimester. But it declined in the second trimester. The reference ranges of FT4 for early, middle and late pregnancy were 7.74-14.58, 6.81-12.00 and 6.36-10.99 pmol/L respectively. FT3 rose slightly in the first trimester and then gradually decreased. The reference ranges of FT3 for early, middle and late pregnancy were 3.59-5.59, 3.34-4.91 and 3.09-4.58 pmol/L respectively. As compared with healthy control women in Shenzhen, thyroid function indicators of pregnant women show statistically significant differences. And the establishment of indicators of women's thyroid function reference intervals for different trimesters has important clinical significance in Shenzhen.

Role of color Doppler in differentiation of Graves' disease and thyroiditis in thyrotoxicosis

PubMed Central

Donkol, Ragab Hani; Nada, Aml Mohamed; Boughattas, Sami

2013-01-01

AIM: To evaluate the role of thyroid blood flow assessment by color-flow Doppler ultrasonography in the differential diagnosis of thyrotoxicosis and compare it to technetium pertechnetate thyroid scanning. METHODS: Twenty-six patients with thyrotoxicosis were included in the study. Clinical history was taken and physical examination and thyroid function tests were performed for all patients. Thyroid autoantibodies were measured. The thyroid glands of all patients were evaluated by gray scale ultrasonography for size, shape and echotexture. Color-flow Doppler ultrasonography of the thyroid tissue was performed and spectral flow analysis of both inferior thyroid arteries was assessed. Technetium99 pertechnetate scanning of the thyroid gland was done for all patients. According to thyroid scintigraphy, the patients were divided into two groups: 18 cases with Graves’ disease and 8 cases with Hashimoto’s thyroiditis. All patients had suppressed thyrotropin. The diagnosis of Graves’ disease and Hashimoto’s thyroiditis was supported by the clinical picture and follow up of patients. RESULTS: Peak systolic velocities of the inferior thyroid arteries were significantly higher in patients with Graves’ disease than in patients with thyroiditis (P = 0.004 in the right inferior thyroid artery and P = 0.001 in left inferior thyroid artery). Color-flow Doppler ultrasonography parameters demonstrated a sensitivity of 88.9% and a specificity of 87.5% in the differential diagnosis of thyrotoxicosis. CONCLUSION: Color Doppler flow of the inferior thyroid artery can be used in the differential diagnosis of thyrotoxicosis, especially when there is a contraindication of thyroid scintigraphy by radioactive material in some patients. PMID:23671754

Diagnosis and Treatment of Patients with Thyroid Cancer

PubMed Central

Nguyen, Quang T.; Lee, Eun Joo; Huang, Melinda Gingman; Park, Young In; Khullar, Aashish; Plodkowski, Raymond A.

2015-01-01

Background Thyroid cancer is the most common malignancy of the endocrine system, representing 3.8% of all new cancer cases in the United States and is the ninth most common cancer overall. The American Cancer Society estimates that 62,450 people in the United States will be diagnosed with thyroid cancer in 2015, and 1950 deaths will result from the disease. Objective To review the current approach to the diagnosis and treatment of patients with thyroid cancer. Discussion Over the past 3 decades, there has been a dramatic increase in the number of people diagnosed with thyroid cancer, which may be attributable to the wide use of imaging studies, including ultrasounds, computed tomography, magnetic resonance imaging, and positron emission tomography scans that incidentally detect thyroid nodules. Thyroid cancer is divided into several main types, with papillary thyroid cancer being the most common. The treatment options for patients with thyroid cancer include the surgical removal of the entire thyroid gland (total thyroidectomy), radioactive iodine therapy, and molecular-targeted therapies with tyrosine kinase inhibitors. This article summarizes the diagnosis and treatment of thyroid cancer, with recommendations from the American Thyroid Association regarding thyroid nodules and differentiated thyroid cancer. Recently approved drugs and treatment trends are also explored. Conclusion The prognosis and treatment of thyroid cancer depend on the tumor type and its stage at the time of diagnosis. Many thyroid cancers remain stable, microscopic, and indolent. The increasing treatment options for patients with thyroid cancer, including therapies that were recently approved by the US Food and Drug Administration, have kept the mortality rate from this malignancy low, despite the increase in its incidence. Early diagnosis and appropriate treatment can improve prognosis and reduce mortality. PMID:25964831

[Alpha interferon induced hyperthyroidism: a case report and review of the literature].

PubMed

Maiga, I; Valdes-Socin, H; Thiry, A; Delwaide, J; Sidibe, A T; Beckers, A

2015-01-01

Treatment with alpha interferon in hepatitis C triggers a thyroid autoimmunity in a variable percentage of cases (2-8%). This complication raises some questions about its screening, the possibility to continue anti-viral therapy and thyroid treatment. Alpha interferon has an immunomodulatory effect on the thyroid, but also an inhibitory effect on thyroid hormone synthesis. This explains the occurrence of cases of thyroid dysfunction, which often remain undetected because of their latency. Factors predicting thyroid dysfunction with interferon use are: female sex, history of thyroid disease and previous autoimmunity. Several clinical aspects are encountered including hypothyroidism (the most frequent depending on the series) and hyperthyroidism related to Graves' disease. For their detection, a cooperation between general practionners, gastroenterologists and endocrinologists is mandatory thyroid function tests are requested before, during and after treatment,with alpha interferon. Therapeutic aspects of thyroid disorders range from simple monitoring to symptomatic treatment, such as thyroxine prescription in the presence of hypothyroidism. Antithyroid drugs radioactive iodine or thyroid surgery are used in cases of severe or persistent Graves' disease induced by alpha interferon.

Evaluation of clinical hypothyroidism risk due to irradiation of thyroid and pituitary glands in radiotherapy of nasopharyngeal cancer patients.

PubMed

Lin, Zhixiong; Wang, Xiaoyan; Xie, Wenjia; Yang, Zhining; Che, Kaijun; Wu, Vincent W C

2013-12-01

Radiation-induced thyroid dysfunction after radiotherapy for nasopharyngeal cancer (NPC) has been reported. This study investigated the radiation effects of the thyroid and pituitary glands on thyroid function after radiotherapy for NPC. Sixty-five NPC patients treated with radiotherapy were recruited. Baseline thyroid hormone levels comprising free triiodothyronine (fT3), free thyroxine (fT4) and thyroid-stimulating hormone (TSH) were taken before treatment and at 3, 6, 12 and 18 months. A seven-beam intensity-modulated radiotherapy plan was generated for each patient. Thyroid and pituitary gland dose volume histograms were generated, dividing the patients into four groups: high (>50 Gy) thyroid and pituitary doses (HTHP group); high thyroid and low pituitary doses (HTLP group); low thyroid and high pituitary doses; and low thyroid and pituitary doses. Incidence of hypothyroidism was analysed. Twenty-two (34%) and 17 patients (26%) received high mean thyroid and pituitary doses, respectively. At 18 months, 23.1% of patients manifested various types of hypothyroidism. The HTHP group showed the highest incidence (83.3%) of hypothyroidism, followed by the HTLP group (50%). NPC patients with high thyroid and pituitary gland doses carried the highest risk of abnormal thyroid physiology. The dose to the thyroid was more influential than the pituitary dose at 18 months after radiotherapy, and therefore more attention should be given to the thyroid gland in radiotherapy planning. © 2013 The Royal Australian and New Zealand College of Radiologists.

Associations between Repeated Measures of Maternal Urinary Phthalate Metabolites and Thyroid Hormone Parameters during Pregnancy

PubMed Central

Johns, Lauren E.; Ferguson, Kelly K.; McElrath, Thomas F.; Mukherjee, Bhramar; Meeker, John D.

2016-01-01

Background: Maintaining thyroid homeostasis during pregnancy is essential for normal fetal growth and development. Growing evidence suggests that phthalates interfere with normal thyroid function. Few human studies have investigated the degree to which phthalates may affect thyroid hormone levels in particularly susceptible populations such as pregnant women. Objectives: We examined the associations between repeated measures of urinary phthalate metabolites and plasma thyroid hormone levels in samples collected at up to four time points per subject in pregnancy. Additionally, we investigated the potential windows of susceptibility to thyroid hormone disturbances related to study visit of sample collection. Methods: Data were obtained from pregnant women (n = 439) participating in a nested case–control study of preterm birth with 116 cases and 323 controls. We measured 9 phthalate metabolite concentrations in urine samples collected at up to four study visits per subject during pregnancy (median = 10, 18, 26, and 35 weeks of gestation, respectively). We also measured a panel of thyroid function markers in plasma collected at the same four time points per subject during pregnancy. Results: Although our results were generally null, in repeated measures analyses we observed that phthalate metabolites were largely inversely associated with thyrotropin and positively associated with free and total thyroid hormones. Cross-sectional analyses by study visit revealed that the magnitude and/or direction of these relationships varied by timing of exposure during gestation. Conclusions: These results support previous reports showing the potential for environmental phthalate exposure to alter circulating levels of thyroid hormones in pregnant women. Citation: Johns LE, Ferguson KK, McElrath TF, Mukherjee B, Meeker JD. 2016. Associations between repeated measures of maternal urinary phthalate metabolites and thyroid hormone parameters during pregnancy. Environ Health Perspect 124:1808–1815; http://dx.doi.org/10.1289/EHP170 PMID:27152641

Thyroid function and insulin sensitivity before and after bilio-pancreatic diversion.

PubMed

Gniuli, Donatella; Leccesi, Laura; Guidone, Caterina; Iaconelli, Amerigo; Chiellini, Chiara; Manto, Andrea; Castagneto, Marco; Ghirlanda, Giovanni; Mingrone, Geltrude

2010-01-01

Bilio-pancreatic diversion (BPD) induces permanent weight loss in previously severe obese patients through a malabsorptive mechanism. The aim of the study was to evaluate the modifications of circulating thyroid hormones after BPD, a surgical procedure which interferes with the entero-hepatic circulation of biliary metabolites. Forty-five patients were studied before and 2 years after BPD. Thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), anti-thyroid antibodies, iodine urinary excretion, lipid profile, insulin and glucose plasma levels were assessed. The insulin-resistance HOMA IR index was calculated, and colour Doppler ultrasonography of the neck was performed. The subjects (23%) had subclinical hypothyroidism prior to BPD (TSH levels above the normal range with normal fT3 and fT4 levels). After 2 years 40.42% of the population showed subclinical hypothyroidism, while 6.3% became frankly hypothyroid, all of them with no evidence of auto-immune thyroiditis. Most of the patients, who became sub-clinically hypothyroid only following BPD, had already thyroid alterations at the sonogram (multi-nodular euthyroid goiter and thyroidal cysts) prior to surgery. BPD increases the prevalence of subclinical or even frank hypothyroidism, without causing a defect in thyroid function itself, through several integrated mechanisms. (1) It induces iodine malabsorption, which is partially compensated by iodine excretion contraction. (2) The entero-hepatic open circulation determines fT3 loss, which induces subclinical or frank hypothyroidism in patients with pre-existing thyroid alterations, interfering also with the weight loss progress. Iodine supplementation should be recommended in those patients reporting thyroid alterations at the sonogram prior to BPD, LT4 therapy should be strictly monitored in patients suffering of subclinical hypopthiroidism and T3 therapy should eventually be considered for patients diagnosed with frank hypothyroidism prior to BPD.

Thyroid Disorders in Children and Adolescents with Type 1 Diabetes Mellitus in Isfahan, Iran

PubMed Central

Ardestani, Samaneh Khanpour; Keshteli, Ammar Hassanzadeh; Khalili, Noushin; Hashemipour, Mahin; Barekatain, Reihaneh

2011-01-01

Objective Studies in different populations have shown great variation in the prevalence of thyroid diseases in patients with type 1 diabetes mellitus (T1DM). Our aim was to study the prevalence of thyroid disorders such as autoimmunity of thyroid (AIT), thyroid dysfunction, and goiter in children and adolescents with T1DM, compared with age- and sex-matched healthy controls in Isfahan. Methods One hundred patients with T1DM who were referred to Isfahan Endocrine and Metabolism Research Center and 184 healthy schoolchildren matched for age and sex were included. They were examined for goiter by two endocrinologists. Thyroid function test and serum thyroid antibodies (anti-TPO Ab and anti-Tg Ab) were measured. Findings The prevalence of subclinical hypothyroidism was high in both groups (18%). T1DM patients had lower frequency of goiter (21% vs. 38%, P=0.001), and higher prevalence of positive AIT (22% vs. 8%, P=0.001), anti-TPO Ab positivity (19.3% vs. 5.3%, P=0.000), and anti-Tg Ab (11.1% vs. 6.4%, P=0.1) in comparison with the control group. Being positive for AIT in diabetic patients meant an odds ratio of 5 (CI 95%: 1.5-15.6) for thyroid dysfunction. There was no association between age, sex, duration of diabetes and HbA1C with serum anti-TPO Ab and anti-Tg Ab concentrations in this group. Conclusion Our results demonstrated the high prevalence of AIT and thyroid dysfunction in patients with T1DM. We suggest regular thyroid function and antibody testing in these patients. PMID:23056839

[Study of serum thrombomodulin(TM) levels in patients with hyper- or hypo- thyroidism].

PubMed

Soma, M; Maeda, Y; Matsuura, R; Sasaki, I; Kasakura, S; Saeki, Y; Ikekubo, K; Ishihara, T; Kurahachi, H; Sasaki, S; Tagami, T; Nakao, K

1997-01-01

We studies a relationship between the serum levels of thrombomodulin(TM) and the thyroid functions. Serum TM levels were measured in 48 patients with Graves' disease, 17 patients with primary hypothyroidism, 7 patients with subacute thyroiditis, 5 patients with painless thyroiditis and 2 patients with systematic Refetoff syndrome. These patients did not have malignant tumor, kidney failure, or blood vessel injury. Control sera were obtained from 42 healthy subjects. Serum levels of TM in patients with untreated Graves' disease were significantly higher(p < 0.001) compared with those in controls. Serum levels of TM in patients with hypothyroidism were not significantly changed as compared with those of controls. There were a positive correlation between the serum levels of TM and FT3 as well as FT4. Serial determinations of the serum levels of TM and thyroid function(FT3, FT4 and TH) in patients with Graves' disease during treatment showed that both the serum levels of TM and thyroid hormones (FT3 and FT4) lowered progressively during treatment. After normalization of serum FT3 and FT4, the serum TM levels returned to normal. However, the serum levels of TM in patients with destructive thyroiditis and Refetoff syndrome were normal in spite of high serum levels of thyroid hormones. These data suggest that an increase in serum levels of TM is not the direct result of thyroid hormones themselves but is the result of the prolonged hypermetabolic state induced by their peripheral activities. Thyroid hormones may stimulate the synthesis or metabolism of TM on the surface of vascular endothelial cells in the patients with Graves' disease.

Influence of chronic exposure to cold environment on thyroid gland function in rabbits.

PubMed

Mustafa, S; Elgazzar, A

2014-07-01

Chronic exposure to cold can affect the thyroid gland. However, the effect on thyroid gland perfusion images and the ratio between thyroid hormones secretion were not addressed in any previous study. The present study investigates the effects of chronic cold exposure on thyroid gland function using radionuclide tracer and thyroid hormones secretion concentration. New Zealand white rabbits weighing approximately 1.8-2 kg were kept in a cold room (4°C) for 7 weeks. Thyroid scintigraphy was performed for cold exposed rabbits and a control rabbit group. Each rabbit was injected with 115 MBq (3.1 mCi) technetium-99m pertechnetate (99mTc pertechnetate). Studies were performed using Gamma camera equipped with a low energy, high resolution, pinhole collimator interfaced with a computer. Static images were acquired 20 min after administration of the radiotracer. Rabbits chronically exposed to cold had less body weights than control. Thyroid gland uptake is higher in rabbits chronically exposed to cold than controls using radionuclide perfusion study. The increase was proportional to the time period, so the increase after 7 weeks was greater than 5 weeks. There is also an increase in free triiodothyronine (FT3) and a decrease in free thyroxine (FT4) values. Our results indicate that thyroid gland uptake is higher in rabbits chronically exposed to cold than control and the increase was proportional to the duration. The decrease in rabbit body weights may be related to the increase in metabolism due to the increase of thyroid hormones. Chronic cold exposure also increased the conversion of T4 to T3, which is more potent in thermogenic effect. © Georg Thieme Verlag KG Stuttgart · New York.

Painless thyroiditis complicating with hypercalcemic encephalopathy.

PubMed

Thewjitcharoen, Yotsapon; Lumlertgul, Nuttha

2012-01-01

Severe hypercalcemia has rarely been reported in patients with hyperthyroidism. Although the pathogenesis is not clear; it is believed to be due to activation of osteoclasts resulting in excessive bone resorption. To recognize the unusual cause of hypercalcemia from painless thyroiditis, which could manifest with transient hyperthyroidism in the early stage. A 70-year-old woman presented with watery diarrhea, nausea and vomiting and significant weight loss for two months. Initially, she was misdiagnosed as having Graves'disease from her clinical presentation and thyroid function tests. Oral propylthiouracil was given to treat hyperthyroidism. However two weeks after discharge, she developed altered consciousness due to severe hypercalcemia. After combined treatment of hypercalcemia and severe hyperthyroidism, her symptoms resolved quickly. Later on, her thyroid function tests switched to subclinical hypothyroid at two months after initial presentation. No concurrent pathological conditions could be found to explain the other causes of hypercalcemia. Therefore, painless thyroiditis complicated with severe hypercalcemia was subsequently diagnosed based on her clinical course. Hypercalcemic encephalopathy is an uncommon manifestation of hyperthyroidism that should be kept in mind in patients who demonstrated clinical pictures of hyperthyroidism and alteration of consciousness. Moreover the present case emphasizes the consideration of painless thyroiditis as a differential diagnosis of hyperthyroidism because anti-thyroid medications were not indicated in this condition.