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Sample records for affecting thyroid function

  1. 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 ...

  2. Morpho-functional characteristics of rat fetal thyroid gland are affected by prenatal dexamethasone exposure.

    PubMed

    Manojlović-Stojanoski, Milica N; Filipović, Branko R; Nestorović, Nataša M; Šošić-Jurjević, Branka T; Ristić, Nataša M; Trifunović, Svetlana L; Milošević, Verica Lj

    2014-06-01

    Thyroid hormones (TH) and glucocorticoids strongly contribute to the maturation of fetal tissues in the preparation for extrauterine life. Influence of maternal dexamethasone (Dx) administration on thyroid glands morpho-functional characteristics of near term rat fetuses was investigated applying unbiased stereology. On the 16th day of pregnancy dams received 1.0mg/Dx/kg/b.w., followed by 0.5mg/Dx/kg/b.w. on the 17th and 18th days of gestation. The control females received the same volume of saline. The volume of fetal thyroid was estimated using Cavalieri's principle; the physical/fractionator design was applied for the determination of absolute number of follicular cells in mitosis and immunohistochemically labeled C cells; C cell volume was measured using the planar rotator. The functional activity of thyroid tissue was provided from thyroglobulin (Tg) and thyroperoxidase (TPO) immunohistochemical staining. Applying these design-based modern stereological methods it was shown that Dx treatment of gravid females led to a significant decrease of fetal thyroid gland volume in 19- and 21-day-old fetuses, due to decreased proliferation of follicular cells. The Tg and TPO immunohistochemistry demonstrated that intensive TH production starts and continues during the examined period in control and Dx-exposed fetuses. Under the influence of Dx the absolute number of C cells was lower in both groups of near term fetuses, although unchanged relation between the two populations of endocrine cells, follicular and C cells suggesting that structural relationships within the gland are preserved. In conclusion maternal glucocorticoid administration at the thyroid gland level exerts growth-inhibitory and maturational promoting effects in near term rat fetuses.

  3. THYROID FUNCTION IN DEPRESSION

    PubMed Central

    Boral, G. C.; Ghosh, A. B.; Pal, S. K; Ghosh, K. K.; Nandi, D. N.

    1980-01-01

    SUMMARY Studies on thyroid functions were performed on patients suffering from depression and compared with normal control group. 31 different cases of depression were studied for their thyroid function andshowed a diminished level of T3 and T4 with a concomitant rise in TSH level. When the female population of these 31 cases was compared with their male counterparts the females showed a significantly lower thyroidal functional status than the males. PMID:22058497

  4. 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. PMID:24783015

  5. Affective cycling in thyroid disease

    SciTech Connect

    Tapp, A.

    1988-05-01

    Depression in an elderly man with primary recurrent unipolar depression responded to radioactive iodine treatment of a thyrotoxic nodule, without the addition of psychotropic medications. Two months later, manic symptoms developed concomitant with the termination of the hyperthyroid state secondary to the radioactive iodine treatment. Clinical implications of these findings in relation to the possible mechanism of action of thyroid hormones on affective cycling are discussed.

  6. Thyroid Function in Down Syndrome.

    ERIC Educational Resources Information Center

    Pueschel, Siegfried M.; And Others

    1991-01-01

    This study investigated the thyroid function of 181 patients (mean age 14 years) with Down's syndrome and found more thyroid dysfunctions than in the general population. Periodic thyroid hormone function tests are recommended for Down's syndrome individuals, especially as they get older. (Author/DB)

  7. Thyroid function in hemidecorticate rats.

    PubMed

    Munhoz, C O; Tosello, D O; Fernandez, G A; Merzel, J

    1988-01-01

    1. Thyroid function was evaluated in hemidecorticate (HD) and control (C) rats by determining serum T3 and T4 levels and the development of incisors and mandibles and through analysis of various histological features of the thyroid such as follicle size, colloid droplet content and [3H]-glycine uptake by follicular cells. 2. HD animals presented normal levels of circulating T3 but significantly lower T4 levels. 3. There was slight atrophy of the gland in HD animals and fewer colloid droplets were present in the cytoplasm of the follicular cells in this group, indicating a reduction in the breakdown of thyroglobulin. [3H]-glycine uptake by HD indicated that the rate of thyroglobulin biosynthesis was not altered in the experimental animals. 4. The growth of mandibles (weight) and incisors (weight and length) was reduced in HD compared to the control animals. 5. These results suggest that hemidecortication causes mild hypothyroidism (trophoprivic type) probably by affecting hypothalamic function.

  8. Thermogenesis and thyroid function.

    PubMed

    Freake, H C; Oppenheimer, J H

    1995-01-01

    The past 10 years have seen tremendous progress in the definition of the nuclear mechanism of action of thyroid hormones. Although the way in which these nuclear mechanisms underlie the 3,5,3'-triiodo-L-thyronine (T3)-dependent stimulation of metabolic rate remains to be clarified, evidence favoring non-nuclear pathways is limited. Clearly, T3 stimulates both the production and consumption of energy within cells. It also exerts a number of parallel effects that result in increased oxygen consumption, e.g. on mitochondrial structure and composition; on the metabolism of lipids, carbohydrates, and proteins, and on cardiac function. Additionally, T3 may increase the proton permeability of the inner mitochondrial membrane, which implies that it may decrease the efficiency of energy production. These metabolic effects of T3 appear to be restricted to homeothermic-animals, representing a coordinated response to the challenge of maintaining body temperature. PMID:8527221

  9. Phenylthiourea disrupts thyroid function in developing zebrafish.

    PubMed

    Elsalini, Osama A; Rohr, Klaus B

    2003-01-01

    Thyroid hormone (T4) can be detected in thyroid follicles in wild-type zebrafish larvae from 3 days of development, when the thyroid has differentiated. In contrast, embryos or larvae treated with goitrogens (substances such as methimazole, potassium percholorate, and 6-n-propyl-2-thiouracil) are devoid of thyroid hormone immunoreactivity. Phenythiourea (PTurea; also commonly known as PTU) is widely used in zebrafish research to suppress pigmentation in developing embryos/fry. PTurea contains a thiocarbamide group that is responsible for goitrogenic activity in methimazole and 6-n-propyl-2-thiouracil. In the present study, we show that commonly used doses of 0.003% PTurea abolish T4 immunoreactivity of the thyroid follicles of zebrafish larvae. As development of the thyroid gland is not affected, these data suggest that PTurea blocks thyroid hormone production. Like other goitrogens, PTurea causes delayed hatching, retardation and malformation of embryos or larvae with increasing doses. At doses of 0.003% PTurea, however, toxic side effects seem to be at a minimum, and the maternal contribution of the hormone might compensate for compromised thyroid function during the first days of development.

  10. [Regulation of thyroid and pituitary functions by lipopolysaccharide].

    PubMed

    Iaglova, N V; Berezov, T T

    2010-01-01

    Activation of toll-like receptors-4 by bacterial lipopolysaccharide downregulates pituitary and thyroid function. Besides decrease of thyroid-stimulating hormone secretion lipopolysaccharide affects secretion in follicular thyroid cells directly. The endotoxin partially activates and inhibits different phases of follicular thyrocytes' secretion. Lipopolysaccharide enhances thyroglobulin synthesis and exocytosis into follicular lumen and suppresses its resorbtion. It results in sharp drop of blood thyroxine concentration without decrease of deiodinases-mediated thiroxine to triiodothyronine conversion. Stimulation of the lipopolysaccharide-pretreated thyroid gland with thyroid-stimulating hormone increases resorbtion of thyroglobulin and thyroid hormone production. Combined stimulation of the thyroid gland increases protein bound thyroxine and triiodothyronine serum concentration unlike only TSH stimulation resulting in increase of free thyroid hormone levels. It also proves that binding capacity of thyroid hormone serum transport proteins during nonthyroidal illness syndrome remains normal. PMID:21341506

  11. Neonatal thyroid function: influence of perinatal factors.

    PubMed Central

    Franklin, R C; Carpenter, L M; O'Grady, C M

    1985-01-01

    Indices of thyroid function were measured in 229 healthy term neonates at birth and at 5, 10, and 15 days of age. Results were analysed to assess whether maternal diabetes mellitus, toxaemia of pregnancy, intrapartum fetal distress, duration of labour, method of delivery, asphyxia at birth, race, sex, birthweight, birth length, head circumference, or method of feeding influenced any index. Thyroxine, the free thyroxine index, and free thyroxine concentrations at birth correlated with birthweight. Method of delivery influenced mean thyroxine and free thyroxine index values at birth and at age 5 days. Mean values of triiodothyronine, reverse triiodothyronine, thyroxine binding globulin, and thyroid stimulating hormone were not affected by any of the perinatal factors studied. Birthweight and perhaps method of delivery should be taken into account when interpreting neonatal thyroxine parameters but determination of thyroid stimulating hormone as a screen for congenital hypothyroidism in healthy term neonates circumvents these considerations. PMID:3977386

  12. [AMIODARONE AND THE THYROID FUNCTION].

    PubMed

    Jukić, Tomislav; Punda, Marija; Franceschi, Maja; Staniĉić, Josip; Granić, Roko; Kusić, Zvonko

    2015-01-01

    Amiodarone is a benzofuran derivative that contains up to 40% of iodine. Amiodarone is used for treatment and prevention of life threatening supraventricular and ventricular tachyarrhythmias. The effects on thyroid gland vary from abnormalities in thyroid function tests to overt amiodarone induced hypothyroidism (AIH) and thyrotoxicosis (AIT). Patients with AIH are treated with L-thyroxine and may continue treatment with amiodarone. Two different forms of AIT have to be distinguished: amiodarone induced hyperthyroidism (AIT I) and thyroiditis (AIT II). AIT I is treated with antithyroid drugs, while total thyroidectomy and iodine-131 are used for definitive treatment. AIT II is treated with glucocorticoids. Patients with AIT have to stop treatment with amiodarone. Dronedarone is a less potent antiarrhythmic agent with structural and pharmacological properties similar to amiodarone. Dronedarone is devoid of iodine with fewer adverse effects and therefore it may be used in high risk patients for development of AIT or AIH. PMID:26380478

  13. Low-Normal Thyroid Function and Novel Cardiometabolic Biomarkers

    PubMed Central

    van Tienhoven-Wind, Lynnda J.N.; Dullaart, Robin P.F.

    2015-01-01

    The concept is emerging that low-normal thyroid function, i.e., either higher thyroid-stimulating hormone or lower free thyroxine levels within the euthyroid reference range, could contribute to the development of atherosclerotic cardiovascular disease. It is possible that adverse effects of low-normal thyroid function on cardiovascular outcome may be particularly relevant for specific populations, such as younger people and subjects with high cardiovascular risk. Low-normal thyroid function probably relates to modest increases in plasma total cholesterol, low density lipoprotein cholesterol, triglycerides and insulin resistance, but effects on high density lipoprotein (HDL) cholesterol and non-alcoholic fatty liver disease are inconsistent. Low-normal thyroid function may enhance plasma cholesteryl ester transfer, and contribute to an impaired ability of HDL to inhibit oxidative modification of LDL, reflecting pro-atherogenic alterations in lipoprotein metabolism and HDL function, respectively. Low-normal thyroid function also confers lower levels of bilirubin, a strong natural anti-oxidant. Remarkably, all these effects of low-normal thyroid functional status appear to be more outspoken in the context of chronic hyperglycemia and/or insulin resistance. Collectively, these data support the concept that low-normal thyroid function may adversely affect several processes which conceivably contribute to the pathogenesis of atherosclerotic cardiovascular disease, beyond effects on conventional lipoprotein measures. PMID:25690422

  14. Thyroid function after thermal trauma.

    PubMed

    Smeds, S; Kågedal, B; Liedén, G; Liljedahl, S O

    1981-01-01

    The thyroid function was analyzed for 4-6 weeks in a prospective study of 12 thermally injured patients. The burn size range was 15-90%. Serum concentrations of 3,5,3'-triidothyronine (T3) was suppressed and 3,3',5'-triidothyronine (rT3) was increased. The ratio T3/rT3 was subnormal on the third day after the trauma and normalized after 3 weeks. Thyroxine and the free T4-index were within the normal range. The free T3-index were within the normal range. The TSH concentration was initially low but slowly increasing during the period of study. The concentration of the thyroxine-binding globulin (TBG) varied within the normal range. The T3 resin uptake test varied inversely with the TBG concentration. The concentration of thyroxine-binding prealbumin (TBPA) was subnormal. A control experiment excluded possible interference on the hormone concentrations of administered donor blood and plasma. It is concluded that the thyroid hormones are not responsible for the posttraumatic hypermetabolism in burn injury. The present findings further indicate a depletion of metabolically active thyroid hormones at the cellular level after burn injury. PMID:6803354

  15. Etiopathogenetic factors, thyroid functions and thyroid autoimmunity in melasma patients

    PubMed Central

    Özcan, Nimet; Kılıç, Arzu; Koparal, Suha; Artüz, Ferda; Çakmak, Atıl; Köse, Kenan

    2015-01-01

    Introduction Melasma is a common chronic, acquired pigmentation disorder with a significant impact on the quality of life of patients. Aim To investigate the etiopathogenetic factors, thyroid functions and thyroid autoimmunity in patients with melasma. Material and methods Forty-five women with melasma and 45 age-matched healthy women were included in the study group. A detailed history was taken from the patients including triggering factors of melasma. Serum free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), anti-thyroglobulin (AbTG) and anti-thyroid peroxidase (Ab-TPO) were measured and thyroid ultrasonography was performed for each subject. Results In 26.7% of patients, pregnancy, in 17.8%, oral contraceptive use and in 13.3%, intense sunlight exposure were the triggering factors. 17.8% of patients had a family history of melasma. FT4, TSH and AbTG levels were significantly higher in the patient group. Conclusions The results suggest that a combination of factors including pregnancy, oral contraceptive use, sunlight and genetic factors often trigger melasma. Thyroid hormones and thyroid autoimmunity may also play a role in the pathogenesis which needs to be proven by further studies. PMID:26759539

  16. Impaired thyroid function provoked by neonatal treatment with drugs affecting the maturation of monoaminergic and opioidergic neurons.

    PubMed

    Mess, B; Rúzsás, C; Hayashi, S

    1989-09-01

    The aim of the present work was to study the basal secretion rate and the reactivity of the TSH-thyroid axis in adult rats neonatally exposed to drugs influencing monoaminergic and opioidergic neurons. The early postnatal administration of drugs antagonistic with the dopaminergic or serotoninergic neurons resulted in a persistent higher rate of basal secretion of TSH, while the administration of drugs synergistic with the monoaminergic neuron systems was weakly influential in this respect. The exposure to opioids in the perinatal period resulted in a permanent reduction of serum TSH levels which was even more pronounced when the exposure to morphine was advanced to the fetal period of life. These data raise the possibility that the permanent TSH depressing effect of perinatal administration of opioids is due to their effect exerted on the maturation of the monoaminergic neurons. From the other hand, our results lead to assume that there is a perinatal critical period in the maturation of monoaminergic neurons regulating TSH secretion in the adult age. In accordance with this assumption, the data obtained in rats bearing perinatal neurotoxic destruction of catecholaminergic neurons contribute to the concept that the disturbed maturation of monoaminergic neurons in the supposed critical period of development might lead to permanent deficiency also in the reactivity of the TSH-thyroid axis.

  17. Progress in standardizing and harmonizing thyroid function tests.

    PubMed

    Faix, James D; Miller, W Greg

    2016-09-01

    Iodine is an essential component of thyroid hormone. Because thyroid hormone synthesis is affected by iodine deficiency on the one hand and by excess iodine intake on the other, thyroid function biomarkers may be useful for assessing iodine status and studying the effects of iodine supplementation. However, reference intervals for some of the most useful thyroid function biomarkers, including serum concentrations of thyroid-stimulating hormone (TSH), free thyroxine (FT4), and thyroglobulin, vary widely due to variability in the commercially available immunoassays for these tests. Recognizing the need for standardization of thyroid function testing, the International Federation of Clinical Chemistry and Laboratory Medicine established a working group, later restructured as the Committee for Standardization of Thyroid Function Tests, to examine its feasibility. The committee has established a conventional reference measurement procedure for FT4 and an approach to harmonization of results for TSH. Panels of single-donation human blood specimens that span the measuring interval of the immunoassays were used to assess the performance of commercially available immunoassays and form the basis for their recalibration. Recalibration of the manufacturers' methods for both FT4 and TSH has shown that the variability among immunoassays can be successfully eliminated for euthyroid individuals as well as for patients with thyroid disease. The committee is not investigating the standardization of thyroglobulin at the present time. PMID:27534642

  18. The role of thyroid hormone in testicular development and function.

    PubMed

    Wagner, Márcia Santos; Wajner, Simone Magagnin; Maia, Ana Luiza

    2008-12-01

    Thyroid hormone is a critical regulator of growth, development, and metabolism in virtually all tissues, and altered thyroid status affects many organs and systems. Although for many years testis has been regarded as a thyroid hormone unresponsive organ, it is now evident that thyroid hormone plays an important role in testicular development and function. A considerable amount of data show that thyroid hormone influences steroidogenesis as well as spermatogenesis. The involvement of tri-iodothyronine (T(3)) in the control of Sertoli cell proliferation and functional maturation is widely accepted, as well as its role in postnatal Leydig cell differentiation and steroidogenesis. The presence of thyroid hormone receptors in testicular cells throughout development and in adulthood implies that T(3) may act directly on these cells to bring about its effects. Several recent studies have employed different methodologies and techniques in an attempt to understand the mechanisms underlying thyroid hormone effects on testicular cells. The current review aims at presenting an updated picture of the recent advances made regarding the role of thyroid hormones in male gonadal function.

  19. Elastography Evaluation of Benign Thyroid Nodules in Patients Affected by Hashimoto's Thyroiditis

    PubMed Central

    Cappelli, Carlo; Pirola, Ilenia; Gandossi, Elena; Formenti, Annamaria; Agosti, Barbara; Castellano, Maurizio

    2015-01-01

    The aim of the present prospective study was to evaluate the predictive value of elastography in benign thyroid nodules of patients affected by Hashimoto's thyroiditis (HT). From January 2011 to January 2012, 242 nodules in patients affected by HT were submitted to fine needle aspiration cytology (FNAC). All of the patients underwent sonography and elastography performed before FNAC. 230 (95%) nodules were benign, 8 papillary cancers, and 4 follicular lesions. Score 1 was found in 79.1% of benign lesions (sensitivity 79.1%; specificity 66.7%; PPV 97.8%; NPV 14.3%; accuracy 78.5%; p < 0.05). In order to evaluate the outcome of thyroid ultrasound echogenicity in relation to elastography features of nodule(s), all the patients with benign nodules were stratified according to their hypoechoic pattern of thyroid (mild-moderate and severe). Following stratification score 1 was found in 84.2% of benign nodules (sensitivity 75.0%; specificity 88.9%; PPV 27.3%; NPV 98.4%; accuracy 88.2%; p < 0.0001) of patients with a mild-moderate ultrasound thyroid hypoechogenicity, whereas it was found in 60% of benign nodules (p = 0.715) of patients with a marked thyroid hypoechogenicity. Elastography appears to have limited value in detecting thyroid cancer in patients affected by Hashimoto's thyroiditis with severe hypoechoic thyroid tissue. PMID:26273296

  20. 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

  1. Effect of hyperthermia on the function of thyroid gland.

    PubMed

    Mustafa, S; Al-Bader, M D; Elgazzar, A H; Alshammeri, J; Gopinath, S; Essam, H

    2008-06-01

    Hyperthermia may be a consequence of environmental conditions, bacterial or viral infections and/or thyroid storm. This study investigates the acute effect of body temperature elevation on thyroid function and on its scintigraphy studies. Thyroid scintigraphy was performed on New Zealand White rabbits weighing approximately 3-3.5 kg. Each rabbit was injected with 115 MBq (3.1 mCi) technetium-99 m pertechnetate ((99m)Tc 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. Two days later the same protocol was repeated for the same rabbit after increasing the body temperature by 2 degrees C. The experiment was repeated again after a 2-day interval at 3 degrees C, and then after another 2-day interval at 4 degrees C. Plasma free thyroxine (FT(4)), free triiodothyronine (FT(3)) and thyroid stimulating hormone (TSH) were measured at control and at different hyperthermic temperatures (+2, 3, 4 degrees C). We recorded isometric tension of rabbit thyroid artery strips in organ baths during stepwise temperature elevation. During hyperthermia the decrease in thyroid function and thyroid scintigraphy studies was proportional to body temperature elevation. The recording of isometric tension in rabbit thyroid artery strips in organ baths showed vasoconstriction during hyperthermia which is proportional to the heating temperature. Plasma FT(4) and FT(3) level were decreased while TSH levels were not affected by acute fever. Our results indicate that hyperthermia causes a transient decrease in thyroid gland function and scintigraphic patterns on radionuclide studies. Thus, body temperatures must be measured before radionuclide studies in order to ensure that interpretation of data is not influenced by hyperthermia.

  2. Thyroid status affects number and localization of thyroid hormone receptor expressing mast cells in bone marrow.

    PubMed

    Siebler, T; Robson, H; Bromley, M; Stevens, D A; Shalet, S M; Williams, G R

    2002-01-01

    Thyroid hormone (T(3)) plays a key role in endochondral ossification. The process relies on the coordinated synthesis and degradation of cartilage matrix and is disrupted in juvenile hypothyroidism, leading to abnormal skeletal development. Mast cells synthesize and store matrix-degrading enzymes. We examined whether thyroid status influences skeletal mast cell distribution in growing rats to determine whether they might modulate the actions of T(3) in bone. Tibiae were collected for histological, histochemical, immunohistochemical, and immunofluorescence analysis. Mast cells were increased throughout the bone marrow in hypothyroid rats compared with euthyroid, thyrotoxic, and hypothyroid-thyroxine replaced animals. Large numbers were present in metaphyseal marrow adjacent to the growth plate in hypothyroid animals and cells were distributed evenly throughout the marrow. Very few mast cells were present in metaphyseal marrow in other groups, but their numbers increased with increasing distance from the growth plate. T(3) receptor alpha1 (TRalpha1) was expressed in the nucleus and cytoplasm of skeletal mast cells, whereas TRalpha2 and TRbeta1 were restricted to the cytoplasm. Localization of TRs was not affected by altered thyroid status. Thus, disrupted endochondral ossification in hypothyroidism may be mediated in part by skeletal mast cells, which express TR proteins and may function as T(3) target cells.

  3. Thyroid function in bulimia nervosa.

    PubMed

    Altemus, M; Hetherington, M; Kennedy, B; Licinio, J; Gold, P W

    1996-04-01

    Basal thyroid-stimulating hormone (TSH) and thyroid hormone levels were evaluated in 18 women with bulimia nervosa during a period of active binging and vomiting and again after 7 weeks of abstinence from these behaviors and compared to measures in 27 control women. In 10 of the patients and 11 of the controls, the TSH nocturnal surge was calculated from hourly TSH measurements obtained in the afternoon from 1500 to 1900 h and in the night from 2300 to 0400 h. During the binging phase of the illness patients had lower total triiodothyronine (T3) values than controls (p < .001). After 7 weeks without binge eating or purging, patients had lower T3, total thyroxine (T4), free triiodothyronine, free thyroxine (FT4), reverse triiodothyronine and thyroid-binding globulin (TBG) values compared to controls (p < .01) and significant reductions in T3, T4, FT4 and TBG compared to themselves in the active phase of the illness (p < .02). The reduction in thyroid hormone levels was not due to a reduction in the nocturnal thyrotropin surge, since surge values did not differ between normals and patients at either phase of the illness. Bulimics in the binging phase of the illness showed a positive correlation between caloric intake and TSH values (p < .01), suggesting that food binging may stimulate thyroid activity. In sum, these results show a substantial reduction in thyroid hormone levels after 7 weeks of abstinence from binging and vomiting behaviors.

  4. THYROID FUNCTION IN DIFFERENT PSYCHIATRIC DISORDERS

    PubMed Central

    Boral, G. C.; Ghosh, A. B.; Pal, S. K.; Ghosh, K. K.; Nandi, D. N.

    1980-01-01

    SUMMARY Thyroid function viz. estimation of T3, T4 & TSH (Thyroid Stimulating Hormone) were studied in cases of depression, mania and schizophrenia, each category numbering thirty one. These values were compared with corresponding values estimated in norm.al control group of individuals of identical age, sex and socio economic status. The depressives and schizophrenics showed subclinical or chemical hypothyroidism while the manic showed slightly higher values for T3, and T4, when compared to normal control subjects. PMID:22058463

  5. Thyroid function and bone mineral density among Indian subjects

    PubMed Central

    Marwaha, Raman K.; Garg, M. K.; Tandon, Nikhil; Kanwar, Ratnesh; Narang, Aparna; Sastry, Archna; Bhadra, Kuntal

    2012-01-01

    Background: Thyroid hormones affect bone remodeling in patients with thyroid disease by acting directly or indirectly on bone cells. In view of limited information on correlation of thyroid function with bone mineral density (BMD) in euthyroid subjects, we undertook this study to evaluate the correlation between thyroid function with BMD in subjects with normal thyroid function and subclinical hypothyroidism. Material and Methods: A total of 1290 subjects included in this cross sectional study, were divided in Group-1 with normal thyroid function and Group-2 with subclinical hypothyroidism. Fasting blood samples were drawn for the estimation of serum 25(OH)D, intact parathyroid hormone, total and ionized calcium, inorganic phosphorus, and alkaline phosphatase. BMD at lumbar spine, femur, and forearm was measured. Results: BMD at all sites (radius, femur, and spine) were comparable in both groups. There was no difference in BMD when subjects were divided in tertiles of TSH in either group. In group-1, FT4 and TSH were positively associated with BMD at 33% radius whereas FT3 was negatively associated with BMD at femoral neck in multiple regression analysis after adjustment for age, sex, BMI, 25(OH)D and PTH levels. In group-2, there was no association observed between TSH and BMD at any site. Amongst all study subjects FT4 and FT3 were positively correlated with BMD at lumbar spine and radius respectively among all subjects. Conclusion: TSH does not affect BMD in euthyroid subjects and subjects with subclinical hypothyroidism. Thyroid hormones appear to have more pronounced positive effect on cortical than trabecular bone in euthyroid subjects. PMID:22837919

  6. 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...

  7. Thyroid organotypic rat and human cultures used to investigate drug effects on thyroid function, hormone synthesis and release pathways

    SciTech Connect

    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 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

  8. Post Partum Depression and Thyroid Function

    PubMed Central

    Keshavarzi, Farahnaz; Yazdchi, Katayoun; Rahimi, Mehrali; Rezaei, Mansour; Davarinejad, Omran; Abdoli, Nasrin; Jalili, Mahmood

    2011-01-01

    Objective Risk of depression is particularly high for women during the prenatal period. Various investigators have attempted to establish a link between thyroid function and post partum depression. This study aimed to investigate whether thyroid function differs in women with postpartum depression compared to a control group. Methods In this case-control study, subjects were selected from Obstetrics & Gynecology and Psychiatric clinics of Kermanshah University of Medical Sciences. Forty eight patients suffering from postpartum depression according to Diagnostic and Statistical Manual of Mental Disorders, fourth edition totally revised (DSM-IV-TR), and 65 normal controls underwent diagnostic evaluation by one trained psychiatrist using Structured Clinical Interview for DSM-IV-TR. Then, the demographic questionnaire and the Persian version of Edinburgh Postnatal Depression Scale (EPDS) were completed by the participants. Finally, their thyroid functions were assessed. Data analyses were done using the SPSS program 13. Results No statistically significant differences were observed between thyroid function tests and postpartum depression. According to multiple regression analysis with stepwise method, subjects with lower serum TSH, T3RU, T3 levels, younger age and longer period after delivery tended to have higher EPDS scores (P-value=0.008). Conclusion The present study reports that those women with postpartum depression had a no greater prevalence of thyroid dysfunction than the control subjects. It seems that thyroid dysfunction should be considered in women with postpartum depression individually, but the role of thyroid as an important cause of this condition is not yet established. This suggests that future studies should concentrate on this concept in postpartum depression. PMID:22952534

  9. Serum leptin, thyroxine and thyroid-stimulating hormone levels interact to affect cognitive function among US adults: evidence from a large representative survey.

    PubMed

    Beydoun, May A; Beydoun, Hind A; Shroff, Monal R; Kitner-Triolo, Melissa H; Zonderman, Alan B

    2012-08-01

    Neuroanatomical connections point to possible interactions between areas influencing energy homeostasis and those influencing cognition. We assessed whether serum leptin, thyroxine, and thyroid stimulating hormone (TSH) levels are associated with and interact to influence cognitive performance among US adults. Data from the National Health and Nutrition Examination Survey III (1988-1994) were used. Measures included a battery of neuropsychological tests and serum leptin, thyroxine, and TSH levels (20-59-year-old: n = 1114-2665; 60-90-year-old: n = 1365-5519). Among those 20-59-year-old, the middle tertile of leptin (vs. first tertile) was inversely related to the number of errors on the symbol digits substitution test. Increased thyroxine level was associated with a poorer performance on the serial digits test in the 20-59-year-old, but a better performance on the math test in 60-90-year-old group. TSH was associated with poor performance on various tests in the 20-59-year-old, but better performance in the 60-90-year-old group. Significant antagonistic interactions were found in both age groups between thyroxine, TSH, and leptin for a number of tests, including between leptin and thyroxine in the 60-90-year-old group in their association with word recall-correct score. We found significant associations of our main exposures with cognitive function among US adults, going in opposite directions between age groups in the cases of thyroid hormonal levels, as well as some interactive effects between exposures. It is important to conduct prospective cohort studies to provide further insight into potential interventions that would assess interactive effects of various hormonal replacement regimens.

  10. A functioning pleomorphic carcinoma of the thyroid.

    PubMed Central

    Karnauchow, P. N.

    1976-01-01

    A metastasizing functioning pleomorphic carcinoma of the thyroid displayed a morphologic piture ranging from follicular to sarcomatous and carcinoid-like patterns. Spindle-cell elements were believed to be the result of metaplasia of the follicular epithelium. Development of carcinoid-like lesions in the secondary deposits of tumour supported the contention that so-called parafollicular or c-cells may be a phenomenon of metaplasia and not a histologic entity. The tumour was associated with a chromophobe adenoma of the pituitary and a benign schwannoma of the stomach. Clinically the patient did not show any other endocrinologic abnormalities and lived for 4 years from the time of diagnosis of the thyroid tumour. Images FIG. 1 FIG. 2 FIG. 3 FIG. 4 PMID:1277059

  11. Environmental Perchlorate and Thiocyanate Exposures and Infant Serum Thyroid Function

    PubMed Central

    Braverman, Lewis E.; He, Xuemei; Schuller, Kristin E.; Roussilhes, Alexandra; Jahreis, Katherine A.; Pearce, Elizabeth N.

    2012-01-01

    are ubiquitous, these results do not support the concern that maternal and infant environmental perchlorate and thiocyanate exposures affect infant thyroid function. PMID:22827469

  12. Effects of amiodarone therapy on thyroid function.

    PubMed

    Cohen-Lehman, Janna; Dahl, Peter; Danzi, Sara; Klein, Irwin

    2010-01-01

    Amiodarone is a benzofuran derivative approved for the treatment of cardiac arrhythmias. Traditionally classified as a class III antiarrhythmic agent, amiodarone possesses electrophysiologic properties of all four Vaughan-Williams classes. This drug, however, has high iodine content, and this feature plus the intrinsic effects on the body make amiodarone especially toxic to the thyroid gland. Treatment can result in a range of effects from mild derangements in thyroid function to overt hypothyroidism or thyrotoxicosis. The diagnosis and treatment of amiodarone-induced hypothyroidism is usually straightforward, whereas that of amiodarone-induced thyrotoxicosis and the ability to distinguish between the type 1 and type 2 forms of the disease are much more challenging. Dronedarone was approved in 2009 for the treatment of patients with atrial fibrillation. As amiodarone, dronedarone is a benzofuran derivative with similar electrophysiologic properties. In contrast to amiodarone, however, dronedarone is structurally devoid of iodine and has a notably shorter half-life. In studies reported before FDA approval, dronedarone proved to be associated with significantly fewer adverse effects than amiodarone, making it a more attractive choice for patients with atrial fibrillation or flutter, who are at risk of developing amiodarone-induced thyroid dysfunction.

  13. Thyroid function after mantle irradiation in Hodgkin's disease

    SciTech Connect

    Smith, R.E. Jr.; Adler, R.A.; Clark, P.; Brinck-Johnsen, T.; Tulloh, M.E.; Colten, T.

    1981-01-02

    The thyroid function of 64 patients with Hodgkin's disease who received mantle irradiation during the period 1966 to 1976 was studied. More than two-thirds (44 to 64) had some thyroid dysfunction. Twenty had mild dysfunction manifested by an abnormal thyroid-stimulating hormone response to thyrotropin-releasing hormone. Twenty had what could be termed compensated hypothyroidism while four were overtly hypothyroid. The severity of dysfunction was not related to age, sex, or chemotherapy. We found, however, that decreased thyroid function was inversely proportional to the length of time between a diagnostic lymphangiogram and the radiation therapy. These results are consistent with the hypothesis that the iodine load of the lymphangiogram renders the thyroid gland more radiosensitive. Thyroxine suppression of the thyroid gland during the period from the lymphangiogram through the termination of radiation therapy is suggested as a means of avoiding thyroid injury.

  14. Interactions between thyroid and kidney function in pathological conditions of these organ systems: a review.

    PubMed

    van Hoek, Ingrid; Daminet, Sylvie

    2009-02-01

    Thyroidal status affects kidney function already in the embryonic stage. Thyroid hormones influence general tissue growth as well as tubular functions, electrolyte handling and neural input. Hyper- and hypo-functioning of the thyroid influences mature kidney function indirectly by affecting the cardiovascular system and the renal blood flow, and directly by affecting glomerular filtration, electrolyte pumps, the secretory and absorptive capacity of the tubuli, and the structure of the kidney. Hyperthyroidism accelerates several physiologic processes, a fact which is reflected in the decreased systemic vascular resistance, increased cardiac output (CO), increased renal blood flow (RBF), hypertrophic and hyperplastic tubuli, and increased glomerular filtration rate (GFR). Renal failure can progress due to glomerulosclerosis, proteinuria and oxidative stress. Hypothyroidism has a more negative influence on kidney function. Peripheral vascular resistance is increased with intrarenal vasoconstriction, and CO is decreased, causing decreased RBF. The influence on the different tubular functions is modest, although the transport capacity is below normal. The GFR is decreased up to 40% in hypothyroid humans. Despite the negative influences on glomerular and tubular kidney function, a hypothyroid state has been described as beneficial in kidney disease. Kidney disease is associated with decreased thyroid hormone concentrations caused by central effects and by changes in peripheral hormone metabolism and thyroid hormone binding proteins. Geriatric cats form an animal model of disease because both hyperthyroidism and chronic kidney disease (CKD) have high prevalence among them, and the link between thyroid and kidney affects the evaluation of clinical wellbeing and the possible treatment options. PMID:19133263

  15. Thyroid function tests during first-trimester of pregnancy: a review of literature.

    PubMed

    Mansourian, Azad R

    2010-07-15

    This literature review was conducted to summarize the main points of maternal thyroid function tests, with particular attention in the first trimester of pregnancy which accompanied with significant biochemical and metabolic alteration. The evaluation of thyroid function of either hyperthyroidism and hypothyroidism should be assessed by determination of serum Thyroid Stimulating Hormone (TSH), Thyroxine (T4), Triiodothyronine (T3), Iodine and Thyroid Autoantibodies. Glomerular filtration rate is increased during pregnancy; therefor iodine deficiency should be evaluated during the pregnancy to prevent hypothyroidism. The role which can be played by Human Chronic Gonadotropin (hCG) on stimulating the thyroid gland to become over-active was investigated. Serum level ofthyroglobulin (Tg) and Thyroxin Binding Globulin (TBG) should be assessed for proper assessments of thyroid gland during pregnancy. Thyroid function tests during first-trimester of pregnancy and particularly the reference interval for thyroid function tests for pregnant women in each region has to be established, to prevent mis-diagnosis and irreversible mental and physical adverse affect for growing fetus. PMID:21848058

  16. Thyroid function during the spontaneous course of subacute thyroiditis

    SciTech Connect

    Teixeira, V.L.; Romaldini, J.H.; Rodrigues, H.F.; Tanaka, L.M.; Farah, C.S.

    1985-05-01

    A study of changes in serum T/sub 4/, T/sub 3/, and Tg as well as of serum TSH response to TRH was done in ten patients with subacute thyroiditis, from the acute phase up to 56 mo. All patients had symptoms of thyrotoxicosis. The mean serum T/sub 4/, T/sub 3/, and Tg concentration were significantly higher than in normal subjects. The basal TSH concentrations failed to increase in response to TRH. Mean serum T/sub 3/ and serum Tg levels remained higher than in normal subjects until 4 to 5 mo after the acute phase. Thyroid autoantibodies were absent during the whole period of study. An exaggerated response of TSH to TRH in six out of seven patients was observed from a 2 to 3 mo period until the end of follow-up. All patients with T/sub 3/ to T/sub 4/ ratio above the normal range (7-24 ng/..mu..g) showed also an exaggerated response of TSH to TRH. These data suggest that the spontaneous course of subacute thyroiditis may lead to a low thyroid reserve detectable even 5 yr following the acute phase of the disease.

  17. Neonatal thyroid function: prematurity, prenatal steroids, and respiratory distress syndrome.

    PubMed Central

    Franklin, R C; Purdie, G L; O'Grady, C M

    1986-01-01

    Indices of thyroid function were measured in 97 preterm infants at birth and at 5, 10, and 15 days of age. Triiodothyronine uptake, free thyroxine index, thyroxine, free thyroxine, triiodothyronine, reverse triiodothyronine, and thyroxine binding globulin values at birth correlated with gestational age, whereas thyroid stimulating hormone values did not. Treatment with steroids prenatally had no apparent effect on thyroid function at birth or postnatally. Infants developing respiratory distress syndrome had normal values for all indices at birth. These infants had significantly lower thyroxine, free thyroxine index, free thyroxine, and triiodothyronine values at 5 days of age, while thyroid stimulating hormone values remained normal. This alteration in thyroid function was interpreted as being secondary to respiratory distress syndrome. Gestational maturity and respiratory distress syndrome, if present, must be taken into account when evaluating thyroxine variables in preterm infants, whereas measurement of thyroid stimulating hormone as the screen for congenital hypothyroidism circumvents these considerations. PMID:3729529

  18. Fetal thyroid function: diagnosis and management of fetal thyroid disorders.

    PubMed

    Fisher, D A

    1997-03-01

    The fetal hypothalamic-pituitary-thyroid axis develops independently of the maternal axis, but it is dependent on the maternal-placental system for adequate supply of iodide substrate. This iodide is supplied by direct transfer of maternal plasma iodide and by placental deiodination of T4. In addition, although placental transport of iodothyronines is limited, significant maternal-fetal transfer of T4 occurs, accounting for approximately 30% of the average 10 ug/dL serum-T4 concentration in fetal-cord blood at term. Current information suggests that this maternal contribution to the fetal-T4 levels is important for normal fetal maturation, particularly of the central nervous system. Combined maternal-fetal hypothyroxinemia can lead to irreversible fetal central nervous system damage. The timing of this fetal T4 dependency is not clear. It may be important in the first half of gestation, before the fetal thyroid gland is capable of T4 production, as well as the latter half of gestation when thyroid hormone effects on multiple organ systems are developing. Management of fetal thyroid dysfunction requires normalization of maternal serum T4 concentrations, avoidance or careful monitoring of potentially goitrogenic drug effects in the fetus, and in some instances, direct or indirect fetal therapy. In most cases fetal hypothyroidism is sporadic and undetected, and prognosis for normal growth and development is excellent if the mother is euthyroid and the hypothyroid state is detected and adequately treated at birth. Fetal treatment by intraamniotic thyroxine injection has been provided in cases of inadvertent maternal radioiodine treatment of Graves' disease between 10 and 20 weeks gestation and for fetal goiter detected by ultrasound. Effective treatment of fetal hyperthyroidism in pregnant women with high titers of thyroid stimulating autoantibody is possible by judicious administration of antithyroid drugs to the mother. Management of the hyperthyroid state in the

  19. Generation of functional thyroid from embryonic stem cells.

    PubMed

    Antonica, Francesco; Kasprzyk, Dominika Figini; Opitz, Robert; Iacovino, Michelina; Liao, Xiao-Hui; Dumitrescu, Alexandra Mihaela; Refetoff, Samuel; Peremans, Kathelijne; Manto, Mario; Kyba, Michael; Costagliola, Sabine

    2012-11-01

    The primary function of the thyroid gland is to metabolize iodide by synthesizing thyroid hormones, which are critical regulators of growth, development and metabolism in almost all tissues. So far, research on thyroid morphogenesis has been missing an efficient stem-cell model system that allows for the in vitro recapitulation of the molecular and morphogenic events regulating thyroid follicular-cell differentiation and subsequent assembly into functional thyroid follicles. Here we report that a transient overexpression of the transcription factors NKX2-1 and PAX8 is sufficient to direct mouse embryonic stem-cell differentiation into thyroid follicular cells that organize into three-dimensional follicular structures when treated with thyrotropin. These in vitro-derived follicles showed appreciable iodide organification activity. Importantly, when grafted in vivo into athyroid mice, these follicles rescued thyroid hormone plasma levels and promoted subsequent symptomatic recovery. Thus, mouse embryonic stem cells can be induced to differentiate into thyroid follicular cells in vitro and generate functional thyroid tissue.

  20. Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland.

    PubMed

    Serim, Burcu Dirlik; Korkmaz, Ulku; Can, Unal; Altun, Gulay Durmus

    2016-01-01

    Radionuclide scintigraphy with I-131 and Tc-99m pertechnetate ((99)mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of I-131 and (99)mTc04 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland.

  1. Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland

    PubMed Central

    Serim, Burcu Dirlik; Korkmaz, Ulku; Can, Unal; Altun, Gulay Durmus

    2016-01-01

    Radionuclide scintigraphy with I-131 and Tc-99m pertechnetate (99mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of I-131 and 99mTc04 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland. PMID:27385899

  2. Intrathoracic toxic thyroid nodule causing hyperthyroidism with a multinodular normal functional cervical thyroid gland.

    PubMed

    Serim, Burcu Dirlik; Korkmaz, Ulku; Can, Unal; Altun, Gulay Durmus

    2016-01-01

    Radionuclide scintigraphy with I-131 and Tc-99m pertechnetate ((99)mTc04) has been widely used in detecting toxic nodules. Intrathoracic goiter usually presents as an anterior mediastinal mass. Mostly the connection between intrathoracic mass and the cervical thyroid gland is clearly and easily identified occurring as a result of inferior extension of thyroid tissue in the neck, which is called as secondary intrathoracic goiter. Completely separated, aberrant or in other words primary intrathoracic goiters arise as a result of abnormal embryologic migration of ectopic thyroid closely associated with aortic sac and descend into the mediastinum. Intrathoracic goiters are generally nontoxic nodules existing with mass effect without causing hyperthyroidism. However, mostly reported cases had enlarged thyroid glands in the neck. This report demonstrates the usefulness of I-131 and (99)mTc04 scintigraphy for detecting intrathoracic goiter causing hyperthyroidism with a normal functioned cervical thyroid gland. PMID:27385899

  3. Thyroid Diseases Tests

    MedlinePlus

    ... of thyroiditis and identify autoimmune thyroid conditions Thyroid peroxidase (TPO) antibody—a marker for autoimmune thyroid disease; ... for thyroid gland abnormalities and to evaluate thyroid function (for iodine) in different areas of the thyroid ...

  4. [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.

  5. Thyroid function in fragile-X syndrome males.

    PubMed Central

    Bregman, J. D.; Leckman, J. F.; Ort, S. I.

    1990-01-01

    Twelve males with fragile-X syndrome between the ages of three and 28 years underwent assessment of thyroid function. All 12 subjects demonstrated normal baseline values for thyroid stimulating hormone (TSH), thyroxine, thyroid binding globulin (TBG), and estimated free thyroxine (EFT). Relative to a control group reported in the literature, however, the fragile-X subjects exhibited a blunted TSH response to thyrotropin releasing hormone (TRH). This finding suggests the presence of subtle dysfunction within the hypothalamic-pituitary-thyroid axis. Elevated baseline prolactin levels were also observed among the fragile-X subjects. These results support previous reports of hypothalamic-pituitary abnormalities among fragile-X syndrome males. PMID:2125773

  6. Thyroid

    MedlinePlus

    Thyroid is used to treat the symptoms of hypothyroidism (a condition where the thyroid gland does not produce enough thyroid hormone). Symptoms of hypothyroidism include lack of energy, depression, constipation, weight gain, ...

  7. Thyroiditis

    MedlinePlus

    ... Hashimoto’s thyroiditis is the most common cause of hypothyroidism in the United States. Postpartum thyroiditis, which causes ... hormone levels in the blood) followed by temporary hypothyroidism, is a common cause of thyroid problems after ...

  8. Iodine deficiency, thyroid function and hearing deficit: a review.

    PubMed

    Melse-Boonstra, Alida; Mackenzie, Ian

    2013-12-01

    Iodine deficiency affects an estimated 241 million school-aged children in the world. Little is known about iodine deficiency in relation to auditory function, except for the fact that deaf-mutism is one of the features of cretinism. In the present review, we documented the scientific knowledge on the role of iodine and hypothyroidism in the auditory system. We found that ear development and hearing function depend on thyroid hormones. Multiple pathways are involved in this, including both inner ear morphology as well as neurological processes. Conductive as well as sensorineural hearing loss is found in studies with animals that were rendered hypothyroidic. In humans, auditory impairment is reported frequently in relation to hypothyroidism, ranging from mild disturbances to severe handicap. Auditory impairment has been related more explicitly to congenital hypothyroidism than to acquired hypothyroidism. The critical period for thyroid function-related hearing maturation is the first and second trimesters of pregnancy. Although only a limited number of studies have directly investigated the relationship between iodine deficiency and auditory function, most studies point toward an association. However, evidence from good randomised controlled trials is lacking. Inclusion of auditory outcomes in iodine supplementation studies is therefore to be recommended, especially for trials in pregnancy. Hearing deficit is an invisible abnormality, but has major consequences for educational and social skills if not detected. In view of this, auditory impairment should be mapped in iodine-deficient areas in order to realistically estimate the magnitude of the problem.

  9. Thyroid tumors and thyroid function in women exposed to internal and external radiation

    SciTech Connect

    Polednak, A.P.

    1986-09-01

    The frequency of tumors and other conditions of the thyroid gland were examined in 686 female radium dial workers first employed before 1930, who had a radium body-burden measurement while living (1958-76). If one assumed that the two thyroid cancers ascertained were radiation-induced and that a linear dose-response relationship existed, the estimated thyroid cancer risk was 69 (4-124, 95% confidence range) per 10(6) person-rem thyroid dose equivalent from internal and external radiation. Using data from the Connecticut tumor registry to obtain expected numbers of thyroid cancer, the estimated risk (2 observed vs. 0.67 expected cases) was 46 (95% confidence interval = -19 to 101) excess cases per 10(6) person-rem. Risk estimates were based on crude estimates of external radiation exposure and uncertain quality factors for internal radiation from alpha particles ingested. The frequencies of benign tumor (adenoma), nodules, and goiters were not significantly higher in the higher thyroid-dose groups (5-19, greater than or equal to 20 or greater than or equal to 50 rem) than in the lowest dose group (less than 5 rem). In 1237 female dial workers first employed before 1930, with or without a radium body-burden measurement, no deaths due to thyroid cancer (underlying cause of death on death certificates) were observed during 1950-76, when 0.4 deaths were expected. In a subgroup of 84 Illinois female dial workers who were long-term survivors, means for thyroid function test (T3 resin uptake and free thyroxine index) results did not differ among the thyroid-dose groups.

  10. Reporting Thyroid Function Tests in Pregnancy

    PubMed Central

    McNeil, Alan R; Stanford, Phoebe E

    2015-01-01

    While there is agreement that overt maternal hypothyroidism (serum thyroid stimulating hormone (TSH) >10 mIU/L) should be treated immediately, the evidence is mixed regarding the harm associated with subclinical hypothyroidism and the benefits of thyroxine replacement. The diagnosis of subclinical hypothyroidism rests on the recognition of an increased serum concentration of TSH which may be affected by many factors including gestational age, analytical method, the antibody status of the mother, ethnicity, iodine nutrition and even the time of day when the blood is collected. The 97.5th percentile of TSH at the end of the first trimester is commonly used as the upper boundary of normal in early pregnancy with a default value of 2.5 mIU/L specified in a number of recent clinical guidelines. There have now been numerous papers showing that a more realistic figure is between 3.0 and 4.0 mIU/L depending on the analytical method that is used. There are suggestions that ethnicity may also have a significant effect on TSH and FT4 reference limits in pregnancy. PMID:26900190

  11. Tumour suppressive function of HUWE1 in thyroid cancer.

    PubMed

    Ma, Weiyuan; Zhao, Pengxin; Zang, Leilei; Zhang, Kaili; Liao, Haiying; Hu, Zhigang

    2016-09-01

    HUWE1 (the HECT, UBA, and WWE domain-containing protein 1) is an ubiquitin E3 ligase which plays an important role in coordinating diverse cellular processes. It has been found to be dysregulated in various cancer type and its functions in tumorigenesis remain controversial. The potential tumour suppressive role of HUWE1 in thyroid cancer development was investigated by knocking down HUWE1 in three authentic thyroid cancer cell lines, WRO, FTC133 and BCPAP, followed by various functional assays, including cell proliferation, scratch wound healing and invasion assays. Xenograft experiment was performed to examine in vivo tumour suppressive properties of HUWE1. Small-interfering RNA mediated knockdown of HUWE1 promoted cell proliferation, cell migration and invasion in thyroid cancer cells. Overexpression of HUWE1 conferred partial sensitivity to chemo drugs interfering with DNA replication in these cells. Moreover, HUWE1 was found to be down-regulated in human thyroid cancer tissues compared with matched normal thyroid tissues. In addition, overexpression of HUWE1 significantly inhibited tumour growth in vivo using xenograft mouse models. Mechanistic investigation revealed that HUWE1 can regulate p53 protein level through its stabilization. HUWE1 functions as a tumour suppressor in thyroid cancer progression, which may represent a novel therapeutic target for prevention or intervention of thyroid cancer. PMID:27581931

  12. Thyroid function in critically ill patients.

    PubMed

    Fliers, Eric; Bianco, Antonio C; Langouche, Lies; Boelen, Anita

    2015-10-01

    Patients in the intensive care unit (ICU) typically present with decreased concentrations of plasma tri-iodothyronine, low thyroxine, and normal range or slightly decreased concentration of thyroid-stimulating hormone. This ensemble of changes is collectively known as non-thyroidal illness syndrome (NTIS). The extent of NTIS is associated with prognosis, but no proof exists for causality of this association. Initially, NTIS is a consequence of the acute phase response to systemic illness and macronutrient restriction, which might be beneficial. Pathogenesis of NTIS in long-term critical illness is more complex and includes suppression of hypothalamic thyrotropin-releasing hormone, accounting for persistently reduced secretion of thyroid-stimulating hormone despite low plasma thyroid hormone. In some cases distinguishing between NTIS and severe hypothyroidism, which is a rare primary cause for admission to the ICU, can be difficult. Infusion of hypothalamic-releasing factors can reactivate the thyroid axis in patients with NTIS, inducing an anabolic response. Whether this approach has a clinical benefit in terms of outcome is unknown. In this Series paper, we discuss diagnostic aspects, pathogenesis, and implications of NTIS as well as its distinction from severe, primary thyroid disorders in patients in the ICU.

  13. The effects of ranitidine on pituitary-thyroid function.

    PubMed

    Hine, K R; Harrop, J S; Hopton, M R; Holmes, G K; Matthews, H L

    1984-10-01

    Although several studies have examined the effects of cimetidine on pituitary-thyroid function, few have investigated ranitidine in this respect. We found no changes in thyroid-stimulating-hormone (TSH) or prolactin responses to TSH-releasing-hormone (TRH) in 10 patients with peptic ulcer disease given oral ranitidine. Serum total and free thyroxine (TT4 and FT4) concentrations declined slightly, whereas total and free triiodothyronine (TT3 and FT3) increased slightly following ranitidine. None of these changes achieved statistical significance. Both the ratio of TT4/TT3 and FT4/FT3, however, declined (P less than 0.05) following ranitidine. Thus ranitidine may have a minor influence on peripheral deiodination of thyroxine but has little effect on hormone production from the thyroid gland. The diagnostic value of biochemical tests of thyroid function is not seriously compromised in patients receiving ranitidine.

  14. 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.

  15. 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. PMID:24446160

  16. The effect of short-term low-dose perchlorate on various aspects of thyroid function.

    PubMed

    Lawrence, J E; Lamm, S H; Pino, S; Richman, K; Braverman, L E

    2000-08-01

    Perchlorate (ClO4) salts are found in rocket fuel, fireworks, and fertilizer. Because of ground water contamination, ClO4 has recently been detected in large public water supplies in several states in the 4-18 microg/L (parts per billion [ppb]) range. The potential adverse effect of chronic low level ClO4 ingestion on thyroid function is of concern to the Environmental Protection Agency (EPA). The daily ingestion of ClO4 at these levels would be magnitudes below the therapeutic effect level of hundreds of milligrams of ClO4 used in treating hyperthyroidism. Studies were carried out in nine healthy male volunteers who had normal thyroid function and negative thyroid antibodies to determine whether the ingestion of 10 mg of ClO4 daily (approximately 300 times the estimated maximum amount of ClO4 consumed from the affected water supplies) would affect any aspect of thyroid function. They ingested 10 mg of ClO4 dissolved in a liter of spring water during waking hours for 14 days. Baseline serum thyrotropin (TSH), free thyroxine index (FTI), total triiodothyronine (TT3), 4-, 8-, and 24-hour thyroid 123I uptakes (RAIU), serum and 24-hour urine ClO4, 24-hour urine iodine, complete blood count (CBC), and chemistry profile were determined. All blood and urine tests were repeated on days 7 and 14 of ClO4 administration and thyroid RAIU on day 14 of ClO4 administration. All tests were repeated 14 days after ClO4 was discontinued. No effect of ClO4 on serum thyroid hormone or TSH concentrations, urinary iodine excretion, CBC, or blood chemistry was observed. Urine and serum ClO4 levels were appropriately elevated during the course of ClO4 ingestion in all subjects, demonstrating compliance. By day 14 of ClO4 administration, the 4-, 8-, and 24-hour thyroid RAIU values decreased in all nine subjects by a mean value of 38% from baseline and rebounded above baseline values by 25% at 14 days after ClO4 withdrawal (p < 0.01 analysis of variance (ANOVA) and Tukey). It is well known

  17. Prenatal Thyroxine Treatment Disparately Affects Peripheral and Amygdala Thyroid Hormone Levels

    PubMed Central

    Shukla, Pradeep K.; Sittig, Laura J.; Andrus, Brian M.; Schaffer, Daniel J.; Batra, Kanchi K.; Redei, Eva E.

    2009-01-01

    Summary A prenatal hypothyroid state is associated with behavioral abnormalities in adulthood. Wistar–Kyoto (WKY) rats exhibit hypothyroidism and increased depressive and anxiety-like behaviors. Thus, the WKY could illuminate the mechanisms by which the reversal of developmental hypothyroidism in humans and animals results in adult behavioral improvement. We examined the outcome of maternal thyroxine (T4) treatment on thyroid hormone-regulated functions and adult behavior of the WKY offspring. Pregnant WKY dams completed gestation with and without T4 administration and their adult male offspring were tested. Measures included depressive and anxiety-like behaviors, and thyroid hormone (TH) concentrations in both plasma and specific brain regions. In addition, the expression of two proteins affecting thyroid hormone trafficking and metabolism, monocarboxylate transporter 8 (MCT-8) and iodothyronine deiodinase type III (Dio3), and of several behavior-altering molecules, glucocorticoid receptor (GR), prepro-thyrotropin releasing hormone (prepro-TRH) and corticotrophin releasing hormone (CRH), were determined in the hippocampus and amygdala of the offspring. Prenatal T4 treatment of WKYs did not affect adult depressive behavior but increased anxiety-like behavior and decreased plasma levels of THs. In the hippocampus of males treated with T4 in utero, Dio3 and MCT-8 protein levels were increased, while in the amygdala, there were increases of free T4, MCT-8, GR, prepro-TRH protein and CRH mRNA levels. These results show that T4 administration in utero programs adult peripheral and amygdalar thyroid hormone levels divergently, and that the resulting upregulation of anxiety-related genes in the amygdala could be responsible for the exacerbated anxiety-like behavior seen in WKYs after prenatal T4 treatment. PMID:20005050

  18. Clinical implications of altered thyroid status in male testicular function.

    PubMed

    Wajner, Simone Magagnin; Wagner, Márcia Santos; Maia, Ana Luiza

    2009-11-01

    Thyroid hormones are involved in the development and maintenance of virtually all tissues. Although for many years the testis was thought to be a thyroid-hormone unresponsive organ, studies of the last decades have demonstrated that thyroid dysfunction is associated not only with abnormalities in morphology and function of testes, but also with decreased fertility and alterations of sexual activity in men. Nowadays, the participation of triiodothyronine (T3) in the control of Sertoli and Leydig cell proliferation, testicular maturation, and steroidogenesis is widely accepted, as well as the presence of thyroid hormone transporters and receptors in testicular cells throughout the development process and in adulthood. But even with data suggesting that T3 may act directly on these cells to bring about its effects, there is still controversy regarding the impact of thyroid diseases on human spermatogenesis and fertility, which can be in part due to the lack of well-controlled clinical studies. The current review aims at presenting an updated picture of recent clinical data about the role of thyroid hormones in male gonadal function. PMID:20126850

  19. Prevalence and Determinants of True Thyroid Dysfunction Among Pediatric Referrals for Abnormal Thyroid Function Tests

    PubMed Central

    Lahoti, Amit; Klein, Jason; Schumaker, Tiffany; Vuguin, Patricia; Frank, Graeme

    2016-01-01

    Background/Aims. Abnormalities in thyroid function tests (TFTs) are a common referral reason for pediatric endocrine evaluation. However, a sizable proportion of these laboratory abnormalities do not warrant therapy or endocrine follow-up. The objectives of this study were (a) to evaluate the prevalence of true thyroid dysfunction among pediatric endocrinology referrals for abnormal TFTs; (b) to identify the historical, clinical, and laboratory characteristics that predict decision to treat. Methods. This was a retrospective chart review of patients evaluated in pediatric endocrinology office during a weekly clinic designated for new referrals for abnormal TFTs in 2010. Results. A total of 230 patients were included in the study. Median age at referral was 12 years (range = 2-18); 56% were females. Routine screening was cited as the reason for performing TFTs by 33% patients. Majority was evaluated for hypothyroidism (n = 206). Elevated thyroid-stimulating hormone was the most common referral reason (n = 140). A total of 41 out of 206 patients were treated for hypothyroidism. Conclusions. Prevalence of hypothyroidism was 20%. Thyroid follow-up was not recommended for nearly one third of the patients. Among all the factors analyzed, an elevated thyroid-stimulating hormone level and antithyroglobulin antibodies strongly correlated with the decision to treat (P < .005). PMID:27336020

  20. Prevalence and Determinants of True Thyroid Dysfunction Among Pediatric Referrals for Abnormal Thyroid Function Tests.

    PubMed

    Lahoti, Amit; Klein, Jason; Schumaker, Tiffany; Vuguin, Patricia; Frank, Graeme

    2016-01-01

    Background/Aims. Abnormalities in thyroid function tests (TFTs) are a common referral reason for pediatric endocrine evaluation. However, a sizable proportion of these laboratory abnormalities do not warrant therapy or endocrine follow-up. The objectives of this study were (a) to evaluate the prevalence of true thyroid dysfunction among pediatric endocrinology referrals for abnormal TFTs; (b) to identify the historical, clinical, and laboratory characteristics that predict decision to treat. Methods. This was a retrospective chart review of patients evaluated in pediatric endocrinology office during a weekly clinic designated for new referrals for abnormal TFTs in 2010. Results. A total of 230 patients were included in the study. Median age at referral was 12 years (range = 2-18); 56% were females. Routine screening was cited as the reason for performing TFTs by 33% patients. Majority was evaluated for hypothyroidism (n = 206). Elevated thyroid-stimulating hormone was the most common referral reason (n = 140). A total of 41 out of 206 patients were treated for hypothyroidism. Conclusions. Prevalence of hypothyroidism was 20%. Thyroid follow-up was not recommended for nearly one third of the patients. Among all the factors analyzed, an elevated thyroid-stimulating hormone level and antithyroglobulin antibodies strongly correlated with the decision to treat (P < .005).

  1. Effects of thyroid function on the course of experimental chronic renal failure in rats.

    PubMed

    Sanai, Toru; Hirano, Tadashi; Nagata, Masaharu; Okuda, Seiya

    2005-01-01

    Thyroid hormone has been reported to affect renal function. To investigate the effects of thyroid hormone on the progression of renal deterioration, thyroid hormone (dried thyroid) and an antithyroid drug (thiamazole) were administered to adriamycin (ADR)-induced renal failure rats. The rats were divided into four groups, including 1) ADR-DT, given dried thyroid and thiamazole; 2) ADR-T, given thiamazole; 3) ADR; and 4) control. The survival rate at the end of the study (22 weeks) was 62.5% in ADR-DT group and 100% in ADR-T, ADR, and control groups, respectively. There was a significant difference in the body weight and pulse rate between ADR-DT and ADR-T or ADR groups, except for the pulse rate at week 6 (P<0.05). The creatinine clearance was greater in the ADR-T group than in the ADR or ADR-DT groups at week 22, and was significantly different between the ADR-T and the ADR-DT groups (P<0.05). The fractional kidney weight and tubular changes were significantly greater in the ADR-DT group than in the ADR-T or ADR groups (P<0.05). The interstitial volume was significantly greater in the ADR-DT group than in the ADR-T group (P<0.05). We therefore conclude that a dried thyroid has an aggravative effect in the tubular changes and relative interstitial volume induced by ADR.

  2. Perchlorate Exposure and Thyroid Function in Ammonium Perchlorate Workers in Yicheng, China

    PubMed Central

    Chen, Hongxia; Wu, Libing; Wang, Xia; Liu, Qin; Ding, Miaohong; Peng, Kailiang; Meng, Zhongji

    2014-01-01

    The impact of low level dust on the thyroid function of workers chronically exposed to ammonium perchlorate (AP) is uncertain and controversial. The aim of this study was to examine whether workers in China with long-term (>3 years) occupational exposure to low levels of AP dust had affected thyroid homeostasis. Mean occupational exposures to AP dust ranged from 0.43 to 1.17 mg/m3. Geometric means of post-shift urinary perchlorate levels were 20.5 µg/L for those exposed and 12.8 µg/L for the controls. No significant differences were found for thyroid function parameters of FT3, FT4, or log TSH or for TPO prevalence or thyroglobulin levels. Additionally, no differences in findings were observed for complete blood count (CBC), serum biochemical profile, or pulmonary function test. Median urinary iodine levels of 172 and 184 µg/L showed that the workers had sufficient iodine intake. This study found no effect on thyroid function from long term, low-level documented exposure to ammonium perchlorate. It is the first study to report both thyroid status parameters and urinary perchlorate, a biomarker of internal perchlorate exposure, in occupationally exposed workers in China. PMID:24810578

  3. Autonomously functioning thyroid nodules in childhood and adolescence

    SciTech Connect

    Croom, R.D. III; Thomas, C.G. Jr.; Reddick, R.L.; Tawil, M.T.

    1987-12-01

    Autonomously functioning thyroid nodules (AFTNs) in children and adolescents (under age 18) are unusual but are not as rare as earlier reports suggested. These lesions have a significantly different biologic potential than similar lesions in older patients. In the younger age group there is a more rapid progression toward toxicity and a higher incidence of thyroid carcinoma. Our experience with 12 patients is combined with those previously reported for identification of a total of 61 children and adolescents with AFTNs, of whom 53 have undergone operation. Hyperthyroidism was present in 15 patients (24.6%), and in six patients (11.3%) the AFTN was due to a well-differentiated thyroid carcinoma. Surgical treatment is advisable for all children and adolescents with AFTNs because of the risks of hyperthyroidism and thyroid carcinoma. Surgical excision (lobectomy is preferred) results in rapid restoration of a euthyroid state for the toxic AFTN and allows histopathologic diagnosis. Therapy with radioiodine is not advisable for treatment of AFTNs in this age group. Thyroid-stimulating hormone suppression should be used for all patients with a diagnosis of thyroid carcinoma.

  4. Human Embryonic Stem Cells Form Functional Thyroid Follicles

    PubMed Central

    Latif, Rauf; Davies, Terry F.

    2015-01-01

    Objective: The molecular events that lead to human thyroid cell speciation remain incompletely characterized. It has been shown that overexpression of the regulatory transcription factors Pax8 and Nkx2-1 (ttf-1) directs murine embryonic stem (mES) cells to differentiate into thyroid follicular cells by initiating a transcriptional regulatory network. Such cells subsequently organized into three-dimensional follicular structures in the presence of extracellular matrix. In the current study, human embryonic stem (hES) cells were studied with the aim of recapitulating this scenario and producing functional human thyroid cell lines. Methods: Reporter gene tagged pEZ-lentiviral vectors were used to express human PAX8-eGFP and NKX2-1-mCherry in the H9 hES cell line followed by differentiation into thyroid cells directed by Activin A and thyrotropin (TSH). Results: Both transcription factors were expressed efficiently in hES cells expressing either PAX8, NKX2-1, or in combination in the hES cells, which had low endogenous expression of these transcription factors. Further differentiation of the double transfected cells showed the expression of thyroid-specific genes, including thyroglobulin (TG), thyroid peroxidase (TPO), the sodium/iodide symporter (NIS), and the TSH receptor (TSHR) as assessed by reverse transcription polymerase chain reaction and immunostaining. Most notably, the Activin/TSH-induced differentiation approach resulted in thyroid follicle formation and abundant TG protein expression within the follicular lumens. On stimulation with TSH, these hES-derived follicles were also capable of dose-dependent cAMP generation and radioiodine uptake, indicating functional thyroid epithelial cells. Conclusion: The induced expression of PAX8 and NKX2-1 in hES cells was followed by differentiation into thyroid epithelial cells and their commitment to form functional three-dimensional neo-follicular structures. The data provide proof of principal that hES cells can be

  5. Toxicity of palmitoyl glycerol to mice: depression of thyroid function

    SciTech Connect

    Trumbo, P.R.; Meuten, D.J.; King, M.W.; Tove, S.B.

    1987-10-01

    Mice given propylthiouracil, a thyroid inhibitor, and fed a diet containing a nontoxic level of rac-1(3)-palmitoyl glycerol showed the hypothermia and mortality expected for a toxic dose, but did not show these signs when linoleate or oleate was added to the diet. Loss of radioiodine from the whole animal and thyroid gland was slower when mice were fed the toxic palmitoyl glycerol diet than when fed the same diet containing 4% safflower oil. However, mice fed the two diets did not differ in the extent of the incorporation of radioiodine, and essentially all was bound to protein in each case. Follicular thyroid cells from mice fed the potentially toxic diet that contained unsaturated fat were normal in appearance. Conversely, cells from mice fed the toxic diet were smaller and more densely stained, showing evidence of glycoprotein inside the cell. These findings show that the thyroid gland is affected by the palmitoyl glycerol diet. However, the thyroid is not the only organ affected, because giving either thyroxine or triiodothyronine had no effect on the toxicity of palmitoyl glycerol.

  6. Thyroid function and cold acclimation in the hamster, Mesocricetus auratus

    SciTech Connect

    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 exposure 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.

  7. Adrenal and thyroid function in the fetus and preterm infant

    PubMed Central

    2014-01-01

    Adrenal and thyroid hormones are essential for the regulation of intrauterine homeostasis, and for the timely differentiation and maturation of fetal organs. These hormones play complex roles during fetal life, and are believed to underlie the cellular communication that coordinates maternal-fetal interactions. They serve to modulate the functional adaptation for extrauterine life during the perinatal period. The pathophysiology of systemic vasopressor-resistant hypotension is associated with low levels of circulating cortisol, a result of immaturity of hypothalamic-pituitary-adrenal axis in preterm infants under stress. Over the past few decades, studies in preterm infants have shown abnormal clinical findings that suggest adrenal or thyroid dysfunction, yet the criteria used to diagnose adrenal insufficiency in preterm infants continue to be arbitrary. In addition, although hypothyroidism is frequently observed in extremely low gestational age infants, the benefits of thyroid hormone replacement therapy remain controversial. Screening methods for congenital hypothyroidism or congenital adrenal hyperplasia in the preterm neonate are inconclusive. Thus, further understanding of fetal and perinatal adrenal and thyroid function will provide an insight into the management of adrenal and thyroid function in the preterm infant. PMID:25379042

  8. Serum polybrominated diphenyl ether concentrations and thyroid function in young children.

    PubMed

    Jacobson, Melanie H; Barr, Dana B; Marcus, Michele; Muir, Andrew B; Lyles, Robert H; Howards, Penelope P; Pardo, Larissa; Darrow, Lyndsey A

    2016-08-01

    Thyroid hormones are essential for proper neurodevelopment in early life. There is evidence that exposure to polybrominated diphenyl ethers (PBDEs) affects thyroid function, but previous studies have been inconsistent, and no studies among children have been conducted in the United States where PBDE levels are particularly high. Serum levels of seven PBDE congeners and thyroid hormones and other thyroid parameters were measured in 80 children aged 1-5 years from the southeastern United States between 2011 and 2012. Parents of the children completed questionnaires with details on demographics and behaviors. Multivariate linear regression models were used to estimate the associations between serum PBDE levels, expressed as quartiles and as log-transformed continuous variables, and markers of thyroid function. BDE-47, 99, 100 and 153 were detected in >60% of samples, and were summed (∑PBDE). PBDE congeners and ∑PBDE were positively associated with thyroid-stimulating hormone (TSH). A log-unit increase in ∑PBDE was associated with a 22.1% increase in TSH (95% CI: 2.0%, 47.7%). Compared with children in the lowest quartile of ∑PBDE exposure, children in higher quartiles had greater TSH concentrations as modeled on the log-scale (second quartile: β=0.32, 95% confidence interval (CI): -0.09, 0.74; third quartile: β=0.44, 95% CI: 0.04, 0.85; and fourth quartile: β=0.49, 95% CI: 0.09, 0.89). There was also a tendency toward lower total T4 and higher free T3 with increasing PBDE exposure. Results suggest that exposure to PBDEs during childhood subclinically disrupts thyroid hormone function, with impacts in the direction of hypothyroidism. PMID:27228485

  9. 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.

  10. Iodopovidone pleurodesis does not effect thyroid function in normal adults.

    PubMed

    Yeginsu, Ali; Karamustafaoglu, Altemur; Ozugurlu, Fikret; Etikan, Ilker

    2007-08-01

    Iodopovidone is an effective, safe, cheap, and easily available agent for pleurodesis. On the other hand, topical applications of iodopovidone may cause thyroid dysfunction. The purpose of this retrospective study was to determine the effects of intrapleural administration of iodopovidone on thyroid function. Twelve patients have undergone iodopovidone pleurodesis so far. A mixture of 20 ml 10% iodopovidone and 80 ml 0.9% saline solution was administered into the pleural cavity through the chest tube. Thyroid hormone (TSH, TT4, TT3, FT4, FT3) levels were routinely measured just before pleurodesis, and at the 24th and 72nd h of pleurodesis. No statistically significant alteration in thyroid function was determined (P>0.05). We did not observe any signs or symptoms of hyper- or hypothyroidism in any patient. Nine patients had a complete response to pleurodesis (75%). One patient who had undergone iodopovidone pleurodesis suffered from a moderate degree of transient chest pain. In conclusion, iodopovidone pleurodesis is safe and does not cause any thyroid dysfunction in normal adults.

  11. Thyroid Function among Breastfed Children with Chronically Excessive Iodine Intakes.

    PubMed

    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

  12. 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

  13. Extent of Surgery Affects Survival for Papillary Thyroid Cancer

    PubMed Central

    Bilimoria, Karl Y.; Bentrem, David J.; Ko, Clifford Y.; Stewart, Andrew K.; Winchester, David P.; Talamonti, Mark S.; Sturgeon, Cord

    2007-01-01

    Background: The extent of surgery for papillary thyroid cancers (PTC) remains controversial. Consensus guidelines have recommended total thyroidectomy for PTC ≥1 cm; however, no study has supported this recommendation based on a survival advantage. The objective of this study was to examine whether the extent of surgery affects outcomes for PTC and to determine whether a size threshold could be identified above which total thyroidectomy is associated with improved outcomes. Methods: From the National Cancer Data Base (1985–1998), 52,173 patients underwent surgery for PTC. Survival was estimated by the Kaplan-Meier method and compared using log-rank tests. Cox Proportional Hazards modeling stratified by tumor size was used to assess the impact of surgical extent on outcomes and to identify a tumor size threshold above which total thyroidectomy is associated with an improvement in recurrence and long-term survival rates. Results: Of the 52,173 patients, 43,227 (82.9%) underwent total thyroidectomy, and 8946 (17.1%) underwent lobectomy. For PTC <1 cm extent of surgery did not impact recurrence or survival (P = 0.24, P = 0.83). For tumors ≥1 cm, lobectomy resulted in higher risk of recurrence and death (P = 0.04, P = 0.009). To minimize the influence of larger tumors, 1 to 2 cm lesions were examined separately: lobectomy again resulted in a higher risk of recurrence and death (P = 0.04, P = 0.04). Conclusions: The results of this study demonstrate that total thyroidectomy results in lower recurrence rates and improved survival for PTC ≥1.0 cm compared with lobectomy. This is the first study to demonstrate that total thyroidectomy for PTC ≥1.0 cm improves outcomes. PMID:17717441

  14. Assessment of thyroid and gonadal function in liver diseases

    PubMed Central

    Kharb, Sandeep; Garg, M. K.; Puri, Pankaj; Brar, Karninder S.; Pandit, Aditi; Srivastava, Sharad

    2015-01-01

    Introduction: Liver is involved with the synthesis of carrier proteins and metabolism of various hormones and liver diseases may, therefore, be associated with various endocrine disturbances. This study was conducted to assess thyroid and gonadal function in subjects with acute hepatitis (AH), chronic liver disease (CLD), and those who had undergone liver transplantation (LT). Materials and Methods: Patients with AH, CLD with Child-Pugh stage A (CLD-1) and Child-Pugh stage B or C (CLD-2), and LT seen at our tertiary level hospital were assessed clinically, biochemically, and for thyroid and gonadal functions besides 25 healthy controls. Results: Thyroid dysfunction and hypogonadism were present in 14 (16%) and 24 (28%) patients with liver diseases respectively. Among thyroid dysfunction, the commonest was sick euthyroid syndrome six (7%), followed by subclinical hypothyroidism in three patients (3.5%), subclinical hyperthyroidism and thyrotoxicosis in two patients each (2.3%) and overt hypothyroidism in one patient. Among patients with LT and AH groups, the only abnormality was significantly lower total T3 compared with healthy controls. The CLD2 group had significantly lower levels of all thyroid hormones compared with controls and CLD1 group. Hypogonadism was commonest in patients with CLD-2 (14; 50%) followed by LT (3; 33%), CLD-1 (4; 20%), and AH (3; 14%). Hypogonadism was predicted by older age, lower levels of serum albumin, total cholesterol, and triglycerides and higher levels of plasma glucose, serum bilirubin, aspartate transaminases, and international normalized ratio. Gonadal functions showed recovery following LT. Conclusions: Thyroid dysfunction and hypogonadism form an important part of the spectrum of acute and CLD, and patients with LT. Deterioration of synthetic functions of liver disease predicts presence of hypogonadism. PMID:25593833

  15. Rescue from dwarfism by thyroid function compensation in rdw rats.

    PubMed

    Furudate, Sen-ichi; Ono, Masao; Shibayama, Keiko; Ohyama, Yoshihide; Kuwada, Masahiro; Kimura, Toshimi; Kameya, Toru

    2005-10-01

    The rdw rat was initially reported as having hereditary dwarfism caused by pituitary dysfunction. Subsequent studies on the rdw rat, however, have demonstrated that the primary cause of rdw dwarfism is present in the thyroid gland but not in the pituitary gland. The primary cause of rdw rat disorders is a missense mutation of the thyroglobulin (Tg) gene by a one-point mutation. In the present study, we attempted to rescue the dwarfism of the rdw rats using a diet supplemented with thyroid powder (T-powder) and a thyroid graft (T-graft). The infants of the rdw rat were successfully raised to a mature stage body weight, accompanied by elevation of serum growth hormone (GH) and prolactin (PRL), by the T-powder. Furthermore, the T-graft successfully increased the body weight with fertility. The serum GH and PRL levels in the T-graft rdw rat significantly increased. The serum thyroid-stimulating hormone (TSH) levels in the T-graft rdw rat were significantly decreased but were significantly higher than those in the control rat. The GH and PRL mRNA expression in the rdw rat with the T-graft was virtually the same as that of the control, but the TSH beta mRNA differed from that of the control rats. Thus, the dwarfism in the rdw rat is rescued by thyroid function compensation, such as that afforded by T-powder and T-graft.

  16. Pitfalls in the measurement and interpretation of thyroid function tests.

    PubMed

    Koulouri, Olympia; Moran, Carla; Halsall, David; Chatterjee, Krishna; Gurnell, Mark

    2013-12-01

    Thyroid function tests (TFTs) are amongst the most commonly requested laboratory investigations in both primary and secondary care. Fortunately, most TFTs are straightforward to interpret and confirm the clinical impression of euthyroidism, hypothyroidism or hyperthyroidism. However, in an important subgroup of patients the results of TFTs can seem confusing, either by virtue of being discordant with the clinical picture or because they appear incongruent with each other [e.g. raised thyroid hormones (TH), but with non-suppressed thyrotropin (TSH); raised TSH, but with normal TH]. In such cases, it is important first to revisit the clinical context, and to consider potential confounding factors, including alterations in normal physiology (e.g. pregnancy), intercurrent (non-thyroidal) illness, and medication usage (e.g. thyroxine, amiodarone, heparin). Once these have been excluded, laboratory artefacts in commonly used TSH or TH immunoassays should be screened for, thus avoiding unnecessary further investigation and/or treatment in cases where there is assay interference. In the remainder, consideration should be given to screening for rare genetic and acquired disorders of the hypothalamic-pituitary-thyroid (HPT) axis [e.g. resistance to thyroid hormone (RTH), thyrotropinoma (TSHoma)]. Here, we discuss the main pitfalls in the measurement and interpretation of TFTs, and propose a structured algorithm for the investigation and management of patients with anomalous/discordant TFTs. PMID:24275187

  17. Thyroid function following neck irraidation for malignant lymphoma

    SciTech Connect

    Kim, Y.H.; Fayos, J.V.; Sisson, J.C.

    1980-01-01

    Thyroid function tests for T/sub 3/ resin (T/sub 3/-r), serum thyroxine (T/sub 4/), and serum thyroid stimulating hormone (TSH) were measured in 70 consecutive patients who had previously undergone lymphangiography and neck irradiation for malignant lymphoma. All were in remission and clinically euthyroid. The abnormalities found were: 23 (33%) patients hypothyroid by TSH, 14 (20%) with subnormal T/sub 4/, and 21 (30%) with subnormal T/sub 3/-r values. None of the patients were biochemically hyperthyroid. The prevalence and magnitude of abnormalities were highest during the third year after irradiation, thereafter decreasing with time.

  18. Environmental factors altering thyroid function and their assessment.

    PubMed Central

    Barsano, C P

    1981-01-01

    Chronic ingestion of modest doses of dietary iodine, radiation, and polyhalogenated biphenyls (PCB's and PBB's) are environmental factors with known or suspected adverse effects on the human thyroid. Iodine consumption in the United States is approaching 1 mg daily for a large segment of the population. Data are reviewed which support the need for concern regarding the long-term adverse effects of dietary iodine on thyroid function, particularly in certain susceptible individuals. Environmental sources of radiation pose a significant risk of thyroid cancer and hypothyroidism under certain circumstances which may be intentional, inadvertent, or accidental. Exposure to polyhalogenated biphenyls during manufacture or as industrial pollutants are hazardous to man and to wildlife in moderate or large quantities and perhaps also in small amounts. The need to investigate the potential harm posed by these factors in the quantities commonly encountered is emphasized. PMID:6263611

  19. Thyroid gland function during the systemic graft versus host reaction

    SciTech Connect

    Kozlova, T.D.; Fedorov, G.N.; Molotkov, O.V.

    1986-04-01

    The aims of the present investigation were as follows: to determine the level of thyroid hormones and thyrotrophin (TSH) at various times after induction of graft versus host reaction (GVHR); to study the degree of /sup 125/ I uptake by thyroid gland tissue at the same times of the GVHR, and to determine correlation between the hormone levels and weight of the gland in the animals and also the body weight of the recipients. Serum levels of tri-iodothyronine (T/sub 3/), thyroxine (T/sub 4/), and TSH were determined by radioimmunoassay. /sup 125/ /SUB I/ was injected intraperitoneally in a dose of 3-4 microCi/100 g body weight. During the development of a systemic GVHR marked inhibition of thyroid function was discovered.

  20. Development of a Novel Thyroid Function Fluctuated Animal Model for Thyroid-Associated Ophthalmopathy

    PubMed Central

    Tu, Yunhai; Wang, Yilong; Ding, Luna; Zhang, Jiao; Wu, Wencan

    2016-01-01

    Background The establishment of a suitable and stable animal model is critical for research on thyroid-associated ophthalmopathy (TAO). In clinical practice, we found that patients treated with I-131 often exhibit TAO; therefore, we aimed to establish a novel thyroid function fluctuated animal model of TAO by simulating the clinical treatment process. Methods We treated SD rats with I-131 to damage the thyroid and then used sodium levothyroxine (L-T4) to supplement the thyroid hormone (TH) levels every seven days, leading to a fluctuating level of thyroid hormones that simulated the status of clinical TAO patients. Rats administered normal saline were considered as a control. The weight, intraocular pressure, and serum T3, T4, TSH and TRAb levels of the rats were measured, and the pathological changes were analyzed by H&E staining and transmission electron microscopy (TEM). Results The experimental rats (TAO group) exhibited significantly reduced weight and elevated intraocular pressure compared with the control rats. Meanwhile, the serum levels of T3 and T4 were up-regulated in the TAO group, but the TSH level decreased during the 10-week study. Moreover, increased numbers of blood vessels and inflammatory cell infiltrations were observed in the orbital tissues of the TAO rats, while no abnormal changes occurred in the control rats. The orbital myofibrils in the TAO rats appeared fractured and dissolved, with twisted structures. Mitochondrial swelling and vacuoles within the endoplasmic reticulum, swelling nerve fibers, shedding nerve myelin, and macrophages were found in the TAO group. Conclusion Rats treated with I-131 and sodium levothyroxine exhibited characteristics similar to those of TAO patients in the clinic, providing an effective and simple method for the establishment of a stable animal model for research on the pathogenesis and treatment of TAO. PMID:26872324

  1. Thyroid hormone signaling controls hair follicle stem cell function.

    PubMed

    Contreras-Jurado, Constanza; Lorz, Corina; García-Serrano, Laura; Paramio, Jesus M; Aranda, Ana

    2015-04-01

    Observations in thyroid patients and experimental animals show that the skin is an important target for the thyroid hormones. We previously showed that deletion in mice of the thyroid hormone nuclear receptors TRα1 and TRβ (the main thyroid hormone-binding isoforms) results in impaired epidermal proliferation, hair growth, and wound healing. Stem cells located at the bulges of the hair follicles are responsible for hair cycling and contribute to the regeneration of the new epidermis after wounding. Therefore a reduction in the number or function of the bulge stem cells could be responsible for this phenotype. Bulge cells show increased levels of epigenetic repressive marks, can retain bromodeoxyuridine labeling for a long time, and have colony-forming efficiency (CFE) in vitro. Here we demonstrate that mice lacking TRs do not have a decrease of the bulge stem cell population. Instead, they show an increase of label-retaining cells (LRCs) in the bulges and enhanced CFE in vitro. Reduced activation of stem cells leading to their accumulation in the bulges is indicated by a strongly reduced response to mobilization by 12-O-tetradecanolyphorbol-13-acetate. Altered function of the bulge stem cells is associated with aberrant activation of Smad signaling, leading to reduced nuclear accumulation of β-catenin, which is crucial for stem cell proliferation and mobilization. LRCs of TR-deficient mice also show increased levels of epigenetic repressive marks. We conclude that thyroid hormone signaling is an important determinant of the mobilization of stem cells out of their niche in the hair bulge. These findings correlate with skin defects observed in mice and alterations found in human thyroid disorders.

  2. [Ontogenetic aspects of morphological and functional characteristics of the thyroid gland in birds].

    PubMed

    Pateiuk, A V; Kuznik, B I; Rusaeva, N S; Baranchugova, L M

    2008-01-01

    One can distinguish two most important periods in postnatal ontogenesis of the thyroid gland in birds. On the 5th postnatal day dramatic enhancement of adenohypophyseal endocrine functioning causes thyrocitic activation, which results in elevated levels of the thyroid hormones. The morphological and functional peak of the thyroid gland is within 3-12 months. Old birds manifest reduced production of the thyroid-stimulating hormone and show morphological changes in the parenchyma and stroma of the thyroid gland which eventually result in diminished production of the thyroid hormones.

  3. The Oncogenic Activity of RET Point Mutants for Follicular Thyroid Cells May Account for the Occurrence of Papillary Thyroid Carcinoma in Patients Affected by Familial Medullary Thyroid Carcinoma

    PubMed Central

    Melillo, Rosa Marina; Cirafici, Anna Maria; De Falco, Valentina; Bellantoni, Marie; Chiappetta, Gennaro; Fusco, Alfredo; Carlomagno, Francesca; Picascia, Antonella; Tramontano, Donatella; Tallini, Giovanni; Santoro, Massimo

    2004-01-01

    Activating germ-line point mutations in the RET receptor are responsible for multiple endocrine neoplasia type 2-associated medullary thyroid carcinoma (MTC), whereas somatic RET rearrangements are prevalent in papillary thyroid carcinomas (PTCs). Some rare kindreds, carrying point mutations in RET, are affected by both cancer types, suggesting that, under specific circumstances, point mutations in RET can drive the generation of PTC. Here we describe a family whose siblings, affected by both PTC and MTC, carried a germ-line point mutation in the RET extracellular domain, converting cysteine 634 into serine. We tested on thyroid follicular cells the transforming activity of RET(C634S), RET(K603Q), another mutant identified in a kindred with both PTC and MTC, RET(C634R) a commonly isolated allele in MEN2A, RET(M918T) responsible for MEN2B and also identified in kindreds with both PTC and MTC, and RET/PTC1 the rearranged oncogene that characterizes bona fide PTC in patients without MTC. We show that the various RET point mutants, but not wild-type RET, scored constitutive kinase activity and exerted mitogenic effects for thyroid PC Cl 3 cells, albeit at significantly lower levels compared to RET/PTC1. The low mitogenic activity of RET point mutants paralleled their reduced kinase activity compared to RET/PTC. Furthermore, RET point mutants maintained a protein domain, the intracellular juxtamembrane domain, that exerted negative effects on the mitogenic activity. In conclusion, RET point mutants can behave as dominant oncogenes for thyroid follicular cells. Their transforming activity, however, is rather modest, providing a possible explanation for the rare association of MTC with PTC. PMID:15277225

  4. Thyroid dysfunction and subfertility.

    PubMed

    Cho, Moon Kyoung

    2015-12-01

    The thyroid hormones act on nearly every cell in the body. Moreover, the thyroid gland continuously interacts with the ovaries, and the thyroid hormones are involved in almost all phases of reproduction. Thyroid dysfunctions are relatively common among women of reproductive age, and can affect fertility in various ways, resulting in anovulatory cycles, high prolactin levels, and sex hormone imbalances. Undiagnosed and untreated thyroid disease can be a cause of subfertility. Subclinical hypothyroidism (SCH), also known as mild thyroid failure, is diagnosed when peripheral thyroid hormone levels are within the normal reference laboratory range, but serum thyroid-stimulating hormone levels are mildly elevated. Thyroid autoimmunity (TAI) is characterized by the presence of anti-thyroid antibodies, which include anti-thyroperoxidase and anti-thyroglobulin antibodies. SCH and TAI may remain latent, asymptomatic, or even undiagnosed for an extended period. It has also been demonstrated that controlled ovarian hyperstimulation has a significant impact on thyroid function, particularly in women with TAI. In the current review, we describe the interactions between thyroid dysfunctions and subfertility, as well as the proper work-up and management of thyroid dysfunctions in subfertile women. PMID:26816871

  5. Thyroid dysfunction and subfertility

    PubMed Central

    2015-01-01

    The thyroid hormones act on nearly every cell in the body. Moreover, the thyroid gland continuously interacts with the ovaries, and the thyroid hormones are involved in almost all phases of reproduction. Thyroid dysfunctions are relatively common among women of reproductive age, and can affect fertility in various ways, resulting in anovulatory cycles, high prolactin levels, and sex hormone imbalances. Undiagnosed and untreated thyroid disease can be a cause of subfertility. Subclinical hypothyroidism (SCH), also known as mild thyroid failure, is diagnosed when peripheral thyroid hormone levels are within the normal reference laboratory range, but serum thyroid-stimulating hormone levels are mildly elevated. Thyroid autoimmunity (TAI) is characterized by the presence of anti-thyroid antibodies, which include anti-thyroperoxidase and anti-thyroglobulin antibodies. SCH and TAI may remain latent, asymptomatic, or even undiagnosed for an extended period. It has also been demonstrated that controlled ovarian hyperstimulation has a significant impact on thyroid function, particularly in women with TAI. In the current review, we describe the interactions between thyroid dysfunctions and subfertility, as well as the proper work-up and management of thyroid dysfunctions in subfertile women. PMID:26816871

  6. Evaluation of thyroid function in diabetes mellitus in Calabar, Nigeria.

    PubMed

    Udiong, C E J; Udoh, A E; Etukudoh, M E

    2007-09-01

    The prevalence of abnormal thyroid hormone levels in diabetes mellitus in Nigeria is not well described. To determine the incidence of abnormal thyroid hormone levels in diabetics in Calabar, Nigeria, fasting blood samples from 161 diabetic subjects and 105 non-diabetic controls were analysed. Free thyroxine (FT), thyroid stimulating hormone (TSH), total triiodothyronine (T(3)) and total thyroxine (T(4)) kits obtained from Biomerica Inc. of USA were used for the analysis. TSH levels (1.80±1.62) in diabetics were significantly lower (p=0.016) than the level in non-diabetic controls (2.34±1.24). Male diabetics had lower (p<0.05) levels of TSH (1.192±0.68 miu/ml) than diabetic females (1.90±1.70 mlu/mt). The level of T(3) in diabetic males (125±97ng/ml) was higher than the level in females (98±75ng/dl). TSH (F=2.74, p=0.049), T(4)(F=56.87, p=0.001), T(3)(F=56.44, P=0.001) in diabetics and FT(4) (F=5.74, p=0.002) in controls showed significant variation with the ages of the subjects. Out of 161 diabetics subjects studies 26.6% had low plasma thyroid hormone levels (FT(4)>2.01 ng/dl). This study has shown a high incidence (46.5%) of abnormal thyroid hormone levels among the diabetics in Nigeria (hypothyroidism 26.6%, hyperthyroidism, 19.9%). The prevalence of hypothyroidism was higher in women (16.8%) than in men (9.9%), while hyperthyroidism was higher in males (11%) than in females (8%). This study has defined thyroid function status of diabetics in Calabar, Nigeria probably the first of such work in Africa. PMID:23105687

  7. Perfluoroalkyl substances and thyroid function in older adults.

    PubMed

    Shrestha, Srishti; Bloom, Michael S; Yucel, Recai; Seegal, Richard F; Wu, Qian; Kannan, Kurunthachalam; Rej, Robert; Fitzgerald, Edward F

    2015-02-01

    Current understanding of the thyroid disruptive properties of perfluoroalkyl substances (PFASs), particularly in aging populations, is limited. The objectives of this study were to (i) assess associations between thyroid function, as measured by serum thyrotropin (thyroid stimulating hormone, TSH), free thyroxine (fT4), total thyroxine (T4), and total triiodothyronine (T3), and serum perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in an aging population and (ii) determine if other persistent organic pollutants with thyroid disruptive properties including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) modify such associations. We conducted a cross-sectional study of 87 men and women 55 to 74years of age, without clinically-diagnosed thyroid disease, who resided in upper Hudson River communities in New York. Geometric means (standard deviations) of serum PFOS and PFOA were 31.6 (1.7) ng/mL and 9.17 (1.72) ng/mL, respectively. Multivariable linear regression analyses indicated that one interquartile range difference in PFOS corresponded to 4% and 9% increases in fT4 and T4 respectively. We detected statistical interactions between PFOA and age for effects on fT4 and T4; joint increases in PFOA and age were associated with increases in fT4 and T4, of 3% and 7%, respectively. We also detected statistical interactions between PFOS and total PCBs for the effect on T3 and between PFOA and total PBDEs for the effect on TSH. Our results suggest that PFASs are associated with subtle alterations in thyroid hormone levels in this population, and that these associations are likely to vary by age, and levels of PCBs and PBDEs. PMID:25483837

  8. Perfluoroalkyl Substances and Thyroid Function in Older Adults

    PubMed Central

    Shrestha, Srishti; Bloom, Michael S.; Yucel, Recai; Seegal, Richard F.; Wu, Qian; Kannan, Kurunthachalam; Rej, Robert; Fitzgerald, Edward F.

    2014-01-01

    Current understanding of the thyroid disruptive properties of perfluoroalkyl substances (PFASs), particularly in aging populations, is limited. The objectives of this study were to (i) assess associations between thyroid function, as measured by serum thyrotropin (thyroid stimulating hormone, TSH), free thyroxine (fT4), total thyroxine (T4), and total triiodothyronine (T3), and serum perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) in an aging population and (ii) determine if other persistent organic pollutants with thyroid disruptive properties including polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs) modify such associations. We conducted a cross-sectional study of 87 men and women 55 to 74 years of age, without clinically-diagnosed thyroid disease, who resided in upper Hudson River communities in New York. Geometric means (standard deviations) of serum PFOS and PFOA were 31.6 (1.7) ng/mL and 9.17 (1.72) ng/mL, respectively. Multivariable linear regression analyses indicated that one interquartile range difference in PFOS corresponded to 4% and 9% increases in fT4 and T4 respectively. We detected statistical interactions between PFOA and age for effects on fT4 and T4; joint increases in PFOA and age were associated with increases in fT4 and T4, of 3% and 7%, respectively. We also detected statistical interactions between PFOS and total PCBs for the effect on T3 and between PFOA and total PBDEs for the effect on TSH. Our results suggest that PFASs are associated with subtle alterations in thyroid hormone levels in this population, and that these associations are likely to vary by age, and levels of PCBs and PBDEs. PMID:25483837

  9. Role of iodine, selenium and other micronutrients in thyroid function and disorders.

    PubMed

    Triggiani, Vincenzo; Tafaro, Emilio; Giagulli, Vito Angelo; Sabbà, Carlo; Resta, Francesco; Licchelli, Brunella; Guastamacchia, Edoardo

    2009-09-01

    Micronutrients, mostly iodine and selenium, are required for thyroid hormone synthesis and function. Iodine is an essential component of thyroid hormones and its deficiency is considered as the most common cause of preventable brain damage in the world. Nowadays about 800 million people are affected by iodine deficiency disorders that include goiter, hypothyroidism, mental retardation, and a wide spectrum of other growth and developmental abnormalities. Iodine supplementation, under form of iodized salt and iodized vegetable oil, produced dramatic improvements in many areas, even though iodine deficiency is still a problem not only for developing countries. In fact, certain subpopulations like vegetarians may not reach an adequate iodine intake even in countries considered iodine-sufficient. A reduction in dietary iodine content could also be related to increased adherence to dietary recommendations to reduce salt intake for preventing hypertension. Furthermore, iodine intakes are declining in many countries where, after endemic goiter eradication, the lack of monitoring of iodine nutrition can lead to a reappearance of goiter and other iodine deficiency disorders. Three different selenium-dependent iodothyronine deiodinases (types I, II, and III) can both activate and inactivate thyroid hormones, making selenium an essential micronutrient for normal development, growth, and metabolism. Furthermore, selenium is found as selenocysteine in the catalytic center of enzymes protecting the thyroid from free radicals damage. In this way, selenium deficiency can exacerbate the effects of iodine deficiency and the same is true for vitamin A or iron deficiency. Substances introduced with food, such as thiocyanate and isoflavones or certain herbal preparations, can interfere with micronutrients and influence thyroid function. Aim of this paper is to review the role of micronutrients in thyroid function and diseases. PMID:19594417

  10. 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…

  11. μ-Crystallin controls muscle function through thyroid hormone action.

    PubMed

    Seko, Daiki; Ogawa, Shizuka; Li, Tao-Sheng; Taimura, Akihiro; Ono, Yusuke

    2016-05-01

    μ-Crystallin (Crym), a thyroid hormone-binding protein, is abnormally up-regulated in the muscles of patients with facioscapulohumeral muscular dystrophy, a dominantly inherited progressive myopathy. However, the physiologic function of Crym in skeletal muscle remains to be elucidated. In this study, Crym was preferentially expressed in skeletal muscle throughout the body. Crym-knockout mice exhibited a significant hypertrophy of fast-twitch glycolytic type IIb fibers, causing an increase in grip strength and high intensity running ability in Crym-null mice. Genetic inactivation of Crym or blockade of Crym by siRNA-mediated knockdown up-regulated the gene expression of fast-glycolytic contractile fibers in satellite cell-derived myotubes in vitro These alterations in Crym-inactivated muscle were rescued by inhibition of thyroid hormone, even though Crym is a positive regulator of thyroid hormone action in nonmuscle cells. The results demonstrated that Crym is a crucial regulator of muscle plasticity, controlling metabolic and contractile properties of myofibers, and thus the selective inactivation of Crym may be a potential therapeutic target for muscle-wasting diseases, such as muscular dystrophies and age-related sarcopenia.-Seko, D., Ogawa, S., Li, T.-S., Taimura, A., Ono, Y. μ-Crystallin controls muscle function through thyroid hormone action. PMID:26718889

  12. Zinc deficiency (ZD) without starvation affects thyroid hormone metabolism of rats

    SciTech Connect

    Lukaski, H.C.; Smith, S.M.; Hall, C.B.; Bucher, D.R. )

    1991-03-15

    Young rats fed diets severely deficient in Zn exhibit impaired growth and endocrine function. These hormone effects may be confounded by cyclical feeding and starvation. To examine the effects of zinc deficiency (ZD) with and without starvation, 40 male weanling Sprague-Dawley rats were fed a semipurified diet containing all essential nutrients and 30 ppm Zn until they weighed 150 g, then were matched by weight into four groups and were fed one of the following diets for 28d: ad lib control Zn diet, marginal ZD diet, severe ZD diet, and C diet pair-fed (PF) in amounts consumed by matched ZD1 rat. Food intake was depressed in ZD1; body weights were reduced in ZD1 and PF. There was no difference in either food intake or weight gain between C and ZD6. ZD reduced liver and femur Zn concentrations. Plasma thyroxine (T{sub 4}) concentration was greater in ZD6 then ZD1 or PF, but less than C; triodothyronine concentration was less in PF than C, but similar to ZD1 and ZD6. Hepatic T{sub 4}-5{prime}-deiodinase activity was greater in ZD6 than ZD1 or PF, but less than C. These findings indicate that altered thyroid hormone metabolism of severe ZD is related to Zn intake and starvation, whereas ZD uncomplicated by starvation affects peripheral deiodination of T{sub 4}, and suggests altered rates of thyroid hormone synthesis or degradation.

  13. Transient changes in thyroid functions tests after zoledronic acid infusion.

    PubMed

    Karga, Helen; Giagourta, Irene; Papaioannou, Garyphallia; Katsichti, Paraskevi; Pardalakis, Argyris; Kassi, Georgia; Zagoreou, Apostolia; Triantaphyllopoulou, Maria; Zerva, Cherry

    2011-01-01

    Zoledronic acid (ZA) induces an acute phase response in association with elevation of serum cytokines, which possibly alter the 3 types of iodothyronine deiodinase activity. We therefore studied the possible alteration in thyroid function tests by ZA. We investigated the acute changes in serum thyroid hormones, TSH, cortisol, white blood cells, CRP, interleukin-6 (IL-6) and tumor necrosis factor (TNF-α), before (0) and 1, 2 and 3 days after iv infusion of 5 mg ZA in 24 asymptomatic postmenopausal women with osteoporosis (ZA group) in comparison with a placebo group. In the majority of patients the ZA infusion was associated with acute phase response and fever within 24h after infusion which became attenuated on day three. Concurrently with increase in serum cortisol, CRP, IL-6 and TNF-α, on day 1 and 2, total serum T3 (TT3), free T3 (fT3), total T4 (TT4) and fT4 decreased with a nadir on day 2 in association with an increase in the fT4/fT3 ratio and reverse T3 (rT3) levels. All thyroid function changes returned to the baseline levels on day 3, with cytokines still at higher levels, although lower than those on day 2. Serum TSH remained essentially unchanged throughout the study. The changes in thyroid hormones were at least in part explained by the increased TNF-α, but not by IL-6. ZA induces short term changes in thyroid hormones, characteristic of nonthyroidal illness syndrome (NTIS), in association with an increase in TNF-α and IL-6.

  14. Do thyroid hormones function in insects?

    PubMed

    Davey, K G

    2000-01-01

    Earlier work demonstrated that phenoxy-phenyl compounds such as fenoxycarb and thyroxine mimicked the effects of JH III in causing a reduction in volume of the follicle cells of Locusta migratoria. While these compounds were only moderately effective, a derivative of thyroxine, 3,3',5-triiodothyronine (T3) was as effective as JH III, and T3 has been shown to bind to the same membrane receptor and activate the same pathway as JH III. The current paper shows that other thyroxine derivatives vary in activity. 3,3', 5'-Triiodothyronine (reverse T3) is inactive. 3,5-Diiodothyronine (T2) is more active than JH III, while its relatives (iodines at 3', 5' or at 3,3') are inactive. When follicles are exposed in vitro to rhodamine conjugated T3, the fluorescent compound can be seen to enter the cells and accumulate there: this process is inhibited by cycloheximide or by a temperature of 0 degrees C. The accumulation is antagonised by JH III but not JH I (which does not bind to the JH III membrane receptor) and by an antiserum raised against the putative membrane receptor protein. The action of T3, but not T2, is inhibited by 6-n-propyl-2-thiouracil or by aurothioglucose, both known to inhibit deiodinases. The activity of T3, but not of T2, increases with time of exposure to the follicle cells. These facts suggest that T3 enters the cells by receptor mediated endocytosis and is converted to a more active compound. Immunoreactivity to T3, but not thyroxine, can be detected in the haemolymph of locusts, and the titre varies slightly with the gonotrophic cycle. The food shows immunoreactivity for both thyroxine and T3. These findings suggest that thyroid hormones are ingested by locusts and have the potential to be used as hormonal signals in the control of egg production.

  15. Phthalates Are Metabolised by Primary Thyroid Cell Cultures but Have Limited Influence on Selected Thyroid Cell Functions In Vitro

    PubMed Central

    Hansen, Juliana Frohnert; Brorson, Marianne Møller; Boas, Malene; Frederiksen, Hanne; Nielsen, Claus Henrik; Lindström, Emma Sofie; Hofman-Bang, Jacob; Hartoft-Nielsen, Marie-Louise; Frisch, Thomas; Main, Katharina M.; Bendtzen, Klaus; Rasmussen, Åse Krogh; Feldt-Rasmussen, Ulla

    2016-01-01

    Phthalates are plasticisers added to a wide variety of products, resulting in measurable exposure of humans. They are suspected to disrupt the thyroid axis as epidemiological studies suggest an influence on the peripheral thyroid hormone concentration. The mechanism is still unknown as only few in vitro studies within this area exist. The aim of the present study was to investigate the influence of three phthalate diesters (di-ethyl phthalate, di-n-butyl phthalate (DnBP), di-(2-ethylhexyl) phthalate (DEHP)) and two monoesters (mono-n-butyl phthalate and mono-(2-ethylhexyl) phthalate (MEHP)) on the differentiated function of primary human thyroid cell cultures. Also, the kinetics of phthalate metabolism were investigated. DEHP and its monoester, MEHP, both had an inhibitory influence on 3'-5'-cyclic adenosine monophosphate secretion from the cells, and MEHP also on thyroglobulin (Tg) secretion from the cells. Results of the lactate dehydrogenase-measurements indicated that the MEHP-mediated influence was caused by cell death. No influence on gene expression of thyroid specific genes (Tg, thyroid peroxidase, sodium iodine symporter and thyroid stimulating hormone receptor) by any of the investigated diesters could be demonstrated. All phthalate diesters were metabolised to the respective monoester, however with a fall in efficiency for high concentrations of the larger diesters DnBP and DEHP. In conclusion, human thyroid cells were able to metabolise phthalates but this phthalate-exposure did not appear to substantially influence selected functions of these cells. PMID:26985823

  16. Prenatal exposure to perfluorinated compounds affects thyroid hormone levels in newborn girls.

    PubMed

    Shah-Kulkarni, Surabhi; Kim, Byung-Mi; Hong, Yun-Chul; Kim, Hae Soon; Kwon, Eun Jin; Park, Hyesook; Kim, Young Ju; Ha, Eun-Hee

    2016-09-01

    Perfluorinated compounds (PFCs) are ubiquitous in the environment and have been detected in humans and wildlife. Exposure to PFCs has decreased in the United States recently, while exposure to PFCs continues in Asian countries, which represents a public health concern. Various mechanisms by which PFCs affect fetal growth have been proposed, such as activation of peroxisome proliferators, disruption of thyroid hormones and changes in lipid metabolism. However, the overall evidence for an association with thyroid hormones is not strong. Therefore, we examined the effect of various prenatal PFCs on cord blood thyroid hormones: triiodothyronine (T3), thyroxine (T4), thyroid stimulating hormone (TSH) levels, and explored the endocrine disrupting effect of these PFCs on thyroid hormone levels in children according to gender. Two hundred and seventy-nine study participants were selected from among the enrolled participants in the Ewha Birth & Growth Retrospective Cohort, a retrospective birth cohort study conducted at Ewha Womans University Hospital, Seoul, Korea between 2006 and 2010. A generalized linear model was constructed to explore the association of PFCs and thyroid hormones. Further, an analysis stratified by gender was conducted. Our study shows that cord blood perfluoro n-pentanoic acid (PFPeA) was positively associated with cord blood T4 (p=0.01) level. Gender-specific analysis showed that prenatal PFCs: PFPeA and Perfluorohexane sulfonic acid (PFHxS) exposure significantly increased T4 (p<0.01) and T3 (p=0.03), respectively, while perfluorononanoic acid (PFNA) decreased TSH (p=0.04) concentration in newborn girls. Thus, prenatal PFC exposure may disrupt thyroid hormone homeostasis. Thyroid hormones play a crucial role in fetal development and may have gender specific action. Hence, these results are of utmost importance in high-risk groups, such as pregnant women and children. PMID:27395336

  17. Studies on the functional relationship between thyroid, adrenal and gonadal hormones.

    PubMed

    Tohei, Atsushi

    2004-02-01

    In order to clarify the functional relationship between thyroid, adrenal and gonadal hormones, hypothyroidism was induced by administration of thiuoracil in adult male and female rats, and the effects of hypothyroidism on the adrenal and the gonadal axes were investigated in the present study. 1. The functional relationship between thyroid and adrenal hormones: Adrenal weights and corticosterone were lowered, whereas the secretion of ACTH, corticotrophin-releasing hormone (CRH) and arginine vasopressin (AVP) increased in hypothyroid rats compared to euthyroid rats. These results indicate that hypothyroidism causes adrenal dysfunction directly and results in hypersecretion of CRH and AVP from the hypothalamus. 2. The functional relationship between thyroid and gonadal hormones: The pituitary response to LHRH was lowered, whereas the testicular response to hCG was not changed in hypothyroid rats. Hypothyroidism suppressed copulatory behavior in male rats. These results suggest that hypothyroidism probably causes dysfunction in gonadal axis at the hypothalamic-pituitary level in male rats. In adult female rats, hypothyroidism inhibited the follicular development accompanied estradiol secretion, whereas plasma concentrations of progesterone and prolactin (PRL) increased in hypothyroid female rats. Hypothyroidism significantly increased the pituitary content of vasoactive intestinal peptide (VIP) though it did not affect dopamine synthesis. These results suggest that hypothyroidism increases pituitary content of VIP and this increased level of VIP likely affects PRL secretion in a paracrine or autocrine manner. In female rats, inhibition of gonadal function in hypothyroid rats mediated by hyperprolactinemia in addition to hypersecretion of endogenous CRH.

  18. Thyroid Hormone Disruption by Water-Accommodated Fractions of Crude Oil and Sediments Affected by the Hebei Spirit Oil Spill in Zebrafish and GH3 Cells.

    PubMed

    Kim, Sujin; Sohn, Ju Hae; Ha, Sung Yong; Kang, Habyeong; Yim, Un Hyuk; Shim, Won Joon; Khim, Jong Seong; Jung, Dawoon; Choi, Kyungho

    2016-06-01

    A crude oil and the coastal sediments that were affected by the Hebei Spirit Oil Spill (HSOS) of Taean, Korea were investigated for thyroid hormone disruption potentials. Water-accommodated fractions (WAFs) of Iranian Heavy crude oil, the major oil type of HSOS, and the porewater or leachate of sediment samples collected along the coast line of Taean were tested for thyroid disruption using developing zebrafish and/or rat pituitary GH3 cells. Major polycyclic aromatic hydrocarbons (PAHs) and their alkylated forms were also measured from the test samples. In zebrafish larvae, significant decreases in whole-body thyroxine (T4) and triiodothyronine (T3) levels, along with transcriptional changes of thyroid regulating genes, were observed following 5 day exposure to WAFs. In GH3 cells, transcriptions of thyroid regulating genes were influenced following the exposure to the sediment samples, but the pattern of the regulatory change was different from those observed from the WAFs. Composition of PAHs and their alkylated homologues in the WAFs could partly explain this difference. Our results clearly demonstrate that WAFs of crude oil can disrupt thyroid function of larval zebrafish. Sediment samples also showed thyroid disrupting potentials in the GH3 cell, even several years after the oil spill. Long-term ecosystem consequences of thyroid hormone disruption due to oil spill deserve further investigation. PMID:27144452

  19. Whole-genome sequence-based analysis of thyroid function.

    PubMed

    Taylor, Peter N; Porcu, Eleonora; Chew, Shelby; Campbell, Purdey J; Traglia, Michela; Brown, Suzanne J; Mullin, Benjamin H; Shihab, Hashem A; Min, Josine; Walter, Klaudia; Memari, Yasin; Huang, Jie; Barnes, Michael R; Beilby, John P; Charoen, Pimphen; Danecek, Petr; Dudbridge, Frank; Forgetta, Vincenzo; Greenwood, Celia; Grundberg, Elin; Johnson, Andrew D; Hui, Jennie; Lim, Ee M; McCarthy, Shane; Muddyman, Dawn; Panicker, Vijay; Perry, John R B; Bell, Jordana T; Yuan, Wei; Relton, Caroline; Gaunt, Tom; Schlessinger, David; Abecasis, Goncalo; Cucca, Francesco; Surdulescu, Gabriela L; Woltersdorf, Wolfram; Zeggini, Eleftheria; Zheng, Hou-Feng; Toniolo, Daniela; Dayan, Colin M; Naitza, Silvia; Walsh, John P; Spector, Tim; Davey Smith, George; Durbin, Richard; Richards, J Brent; Sanna, Serena; Soranzo, Nicole; Timpson, Nicholas J; Wilson, Scott G

    2015-01-01

    Normal thyroid function is essential for health, but its genetic architecture remains poorly understood. Here, for the heritable thyroid traits thyrotropin (TSH) and free thyroxine (FT4), we analyse whole-genome sequence data from the UK10K project (N=2,287). Using additional whole-genome sequence and deeply imputed data sets, we report meta-analysis results for common variants (MAF≥1%) associated with TSH and FT4 (N=16,335). For TSH, we identify a novel variant in SYN2 (MAF=23.5%, P=6.15 × 10(-9)) and a new independent variant in PDE8B (MAF=10.4%, P=5.94 × 10(-14)). For FT4, we report a low-frequency variant near B4GALT6/SLC25A52 (MAF=3.2%, P=1.27 × 10(-9)) tagging a rare TTR variant (MAF=0.4%, P=2.14 × 10(-11)). All common variants explain ≥20% of the variance in TSH and FT4. Analysis of rare variants (MAF<1%) using sequence kernel association testing reveals a novel association with FT4 in NRG1. Our results demonstrate that increased coverage in whole-genome sequence association studies identifies novel variants associated with thyroid function. PMID:25743335

  20. Whole-genome sequence-based analysis of thyroid function.

    PubMed

    Taylor, Peter N; Porcu, Eleonora; Chew, Shelby; Campbell, Purdey J; Traglia, Michela; Brown, Suzanne J; Mullin, Benjamin H; Shihab, Hashem A; Min, Josine; Walter, Klaudia; Memari, Yasin; Huang, Jie; Barnes, Michael R; Beilby, John P; Charoen, Pimphen; Danecek, Petr; Dudbridge, Frank; Forgetta, Vincenzo; Greenwood, Celia; Grundberg, Elin; Johnson, Andrew D; Hui, Jennie; Lim, Ee M; McCarthy, Shane; Muddyman, Dawn; Panicker, Vijay; Perry, John R B; Bell, Jordana T; Yuan, Wei; Relton, Caroline; Gaunt, Tom; Schlessinger, David; Abecasis, Goncalo; Cucca, Francesco; Surdulescu, Gabriela L; Woltersdorf, Wolfram; Zeggini, Eleftheria; Zheng, Hou-Feng; Toniolo, Daniela; Dayan, Colin M; Naitza, Silvia; Walsh, John P; Spector, Tim; Davey Smith, George; Durbin, Richard; Richards, J Brent; Sanna, Serena; Soranzo, Nicole; Timpson, Nicholas J; Wilson, Scott G

    2015-03-06

    Normal thyroid function is essential for health, but its genetic architecture remains poorly understood. Here, for the heritable thyroid traits thyrotropin (TSH) and free thyroxine (FT4), we analyse whole-genome sequence data from the UK10K project (N=2,287). Using additional whole-genome sequence and deeply imputed data sets, we report meta-analysis results for common variants (MAF≥1%) associated with TSH and FT4 (N=16,335). For TSH, we identify a novel variant in SYN2 (MAF=23.5%, P=6.15 × 10(-9)) and a new independent variant in PDE8B (MAF=10.4%, P=5.94 × 10(-14)). For FT4, we report a low-frequency variant near B4GALT6/SLC25A52 (MAF=3.2%, P=1.27 × 10(-9)) tagging a rare TTR variant (MAF=0.4%, P=2.14 × 10(-11)). All common variants explain ≥20% of the variance in TSH and FT4. Analysis of rare variants (MAF<1%) using sequence kernel association testing reveals a novel association with FT4 in NRG1. Our results demonstrate that increased coverage in whole-genome sequence association studies identifies novel variants associated with thyroid function.

  1. Regeneration of Thyroid Function by Transplantation of Differentiated Pluripotent Stem Cells.

    PubMed

    Kurmann, Anita A; Serra, Maria; Hawkins, Finn; Rankin, Scott A; Mori, Munemasa; Astapova, Inna; Ullas, Soumya; Lin, Sui; Bilodeau, Melanie; Rossant, Janet; Jean, Jyh C; Ikonomou, Laertis; Deterding, Robin R; Shannon, John M; Zorn, Aaron M; Hollenberg, Anthony N; Kotton, Darrell N

    2015-11-01

    Differentiation of functional thyroid epithelia from pluripotent stem cells (PSCs) holds the potential for application in regenerative medicine. However, progress toward this goal is hampered by incomplete understanding of the signaling pathways needed for directed differentiation without forced overexpression of exogenous transgenes. Here we use mouse PSCs to identify key conserved roles for BMP and FGF signaling in regulating thyroid lineage specification from foregut endoderm in mouse and Xenopus. Thyroid progenitors derived from mouse PSCs can be matured into thyroid follicular organoids that provide functional secretion of thyroid hormones in vivo and rescue hypothyroid mice after transplantation. Moreover, by stimulating the same pathways, we were also able to derive human thyroid progenitors from normal and disease-specific iPSCs generated from patients with hypothyroidism resulting from NKX2-1 haploinsufficiency. Our studies have therefore uncovered the regulatory mechanisms that underlie early thyroid organogenesis and provide a significant step toward cell-based regenerative therapy for hypothyroidism. PMID:26593959

  2. [Thyroid function in organic lesions of the hypothalamo-pituitary area].

    PubMed

    Szymczak, Jadwiga; Bohdanowicz-Pawlak, Anna; Bednarek-Tupikowska, Gratyna; Bidzińska, Bozena; Dunajska, Katarzyna

    2005-01-01

    The aim of our work was the retrospective evaluation of thyroid function in patients with organic lesions of hypothalamo-pituitary system. In the group of 57 examined patients (31 females and 26 males), 43 were affected by pituitary adenomas, in the other patients organic lesions were caused by other tumors of central nervous system (2), tuberculosis (3) developmental or vascular disorders (5), nonspecific inflammation (1). Pituitary tumors (predominantly macroadenomas) were the cause of acromegaly in 14 cases, Cushing's disease in 9 and hyperprolactinaemia in 5. Next 14 subjects, were affected by nonsecreting pituitary tumors with a visual-field defects or different level of hypopituitarism and diabetes insipidus hypothalamo-hypophyseal. In 6 persons clinical manifestations of hypothyroidism with a low level of free thyroxin and normal TSH were observed. Surgical cure with transsphenoidal or transcranial operation was performed in 54 patients. Next 23 of the patients had lowered thyroxine level as a consequence of surgery. Considering the whole 57 person group with organic lesions of the hypothalamo-pituitary system, 29 patients (50.8%) were affected by secondary or tertiary hypothyroidism as a result of sellar and parasellar area illness or their surgical treatment. We didn't observe any correlation between TSH and FT4 in the patients with normal or low plasma FT4 levels. (1) secondary or tertiary hypothyroidism is a common consequence of organic lesions of the sellar and parasellar area or is due by their surgical treatment; (2) laboratory examination of thyroid function in these patients can not be evaluated only by TSH assessment, but also by thyroid hormone plasma level estimation because of the disturbances in thyroid an hypothalamo-pituitary system feedback. PMID:16238121

  3. No associations exist between mean platelet volume or platelet distribution width and thyroid function in Chinese

    PubMed Central

    Ren, Xiaojun; Meng, Zhaowei; Liu, Ming; Zhu, Mei; He, Qing; Zhang, Qing; Liu, Li; Song, Kun; Jia, Qiyu; Jia, Qiang; Li, Xue; Tan, Jian; Zheng, Wei; Wang, Renfei; Liu, Na; Hu, Tianpeng

    2016-01-01

    Abstract Mean platelet volume (MPV) and platelet distribution width (PDW) are morphometric indices of size distribution and variability of platelet. We aimed to explore the associations between MPV or PDW and thyroid function in a large Chinese cohort. This was a cross-sectional study with a recruitment of 13,622 self-reported healthy Chinese (8424 males, 5198 females). Clinical data of the participants comprised of anthropometric measurements, hepatic function, renal function, serum levels of lipid, glucose, C-reactive protein, erythrocyte sedimentation rate, platelet, MPV, PDW, and thyroid hormones. Database was sorted by sex, and the associations between MPV or PDW and thyroid function were analyzed by quartiles of MPV or PDW. Levels of MPV and PDW were compared in different thyroid function subgroups by 1-way analysis of variance and independent sample's t test. Receiver-operating characteristic (ROC) curve was adopted to determine diagnostic values of MPV and PDW for thyroid dysfunction. Crude and adjusted odds ratios of MPV and PDW for thyroid dysfunction with 95% confidence intervals were analyzed by binary logistic regression models. MPV, PDW, and thyroid stimulation hormone were significantly higher in females than in males. Females showed significantly higher incidence of hypothyroidism and hyperthyroidism than males. However, there were no significant differences of MPV and PDW among different thyroid function subgroups in both sexes, and no obvious correlations were revealed between MPV or PDW and thyroid function. From ROC analysis, we demonstrated no diagnostic values of MPV and PDW for thyroid dysfunction. From binary logistic regression models, no risks of different MPV and PDW quartiles were identified for thyroid dysfunction in both sexes. We could not show any association between MPV or PDW and thyroid function. Prospective studies with better defined risk groups should be performed in the future for further verification and validation. PMID

  4. Sex-specific changes in thyroid gland function and circulating thyroid hormones in nestling American kestrels (Falco sparverius) following embryonic exposure to polybrominated diphenyl ethers by maternal transfer.

    PubMed

    Fernie, Kim J; Marteinson, Sarah C

    2016-08-01

    High concentrations of polybrominated diphenyl ethers (PBDEs) accumulate in predatory birds. Several PBDE congeners are considered thyroid disruptors; however, avian studies are limited. The authors examined circulating thyroid hormones and thyroid gland function of nestling American kestrels (Falco sparverius) at 17 d to 20 d of age, following embryonic exposure by maternal transfer only to environmentally relevant levels of PBDEs (DE-71 technical mixture). Nestlings were exposed to in ovo sum (Σ) PBDE concentrations of 11 301 ± 95 ng/g wet weight (high exposure), 289 ± 33 ng/g wet weight (low exposure), or 3.0 ± 0.5 ng/g wet weight (controls, background exposure). Statistical comparisons are made to controls of the respective sexes and account for the relatedness of siblings within broods. Circulating concentrations of plasma total thyroxine (TT4 ) and total triiodothyronine (TT3 ) in female nestlings were significantly influenced overall by the exposure to DE-71. Following intramuscular administration of thyroid-stimulating hormone, the temporal response of the thyroid gland in producing and/or releasing TT4 was also significantly affected by the females' exposure to DE-71. The altered availability of T4 for conversion to T3 outside of the gland and/or changes in thyroid-related enzymatic activity may explain the lower TT3 concentrations (baseline, overall) and moderately altered temporal TT3 patterns (p = 0.06) of the treatment females. Controlling for the significant effect on TT3 levels of the delayed hatching of treatment females, baseline TT3 levels were significantly and positively correlated with body mass (10 d, 15 d, 20 d), with PBDE-exposed females generally being smaller and having lower TT3 concentrations. Given that exposure concentrations were environmentally relevant, similar thyroidal changes and associated thyroid-mediated processes relating to growth may also occur in wild female nestlings. Environ Toxicol Chem 2016

  5. Sex-specific changes in thyroid gland function and circulating thyroid hormones in nestling American kestrels (Falco sparverius) following embryonic exposure to polybrominated diphenyl ethers by maternal transfer.

    PubMed

    Fernie, Kim J; Marteinson, Sarah C

    2016-08-01

    High concentrations of polybrominated diphenyl ethers (PBDEs) accumulate in predatory birds. Several PBDE congeners are considered thyroid disruptors; however, avian studies are limited. The authors examined circulating thyroid hormones and thyroid gland function of nestling American kestrels (Falco sparverius) at 17 d to 20 d of age, following embryonic exposure by maternal transfer only to environmentally relevant levels of PBDEs (DE-71 technical mixture). Nestlings were exposed to in ovo sum (Σ) PBDE concentrations of 11 301 ± 95 ng/g wet weight (high exposure), 289 ± 33 ng/g wet weight (low exposure), or 3.0 ± 0.5 ng/g wet weight (controls, background exposure). Statistical comparisons are made to controls of the respective sexes and account for the relatedness of siblings within broods. Circulating concentrations of plasma total thyroxine (TT4 ) and total triiodothyronine (TT3 ) in female nestlings were significantly influenced overall by the exposure to DE-71. Following intramuscular administration of thyroid-stimulating hormone, the temporal response of the thyroid gland in producing and/or releasing TT4 was also significantly affected by the females' exposure to DE-71. The altered availability of T4 for conversion to T3 outside of the gland and/or changes in thyroid-related enzymatic activity may explain the lower TT3 concentrations (baseline, overall) and moderately altered temporal TT3 patterns (p = 0.06) of the treatment females. Controlling for the significant effect on TT3 levels of the delayed hatching of treatment females, baseline TT3 levels were significantly and positively correlated with body mass (10 d, 15 d, 20 d), with PBDE-exposed females generally being smaller and having lower TT3 concentrations. Given that exposure concentrations were environmentally relevant, similar thyroidal changes and associated thyroid-mediated processes relating to growth may also occur in wild female nestlings. Environ Toxicol Chem 2016

  6. Thyroid transplantation developing autoimmune thyroiditis following thymectomy and irradiation.

    PubMed Central

    Ahmed, S A; Penhale, W J

    1981-01-01

    Post-irradiation transplantation of normal thyroids under the renal capsule of syngenetic thymectomized and irradiated (Tx-X) rats leads to the development of thyroiditis in the ectopic grafted thyroids. A close correlation was observed between the extent of the lesions in the grafted and recipient's own thyroid. The histopathology of both grafted and recipient thyroid was similar and was characterized by infiltration with mononuclear cells together with some plasma cells. Conversely, grafting of affected thyroids from Tx-X rats to normal animals resulted in the regression of the lesion in the graft and no evidence thyroiditis was observed in either the graft or the recipient's thyroid when these were examined 60 days post-grafting. Thyroids derived from normal animals grafted to syngenetic normal rats were found to remain healthy and intact over a 60-day period. In contrast to normal animals, Tx-X rats were unable to reject totally in transplanted allogeneic thyroids by 28 days post-grafting, suggesting that some impairment of cell-mediated immunity follows this treatment. These findings indicate that the pathological change occurring in the thyroid gland of Tx-X rats is not attributable to the local effect of irradiation of the thyroids and adds further support to the concept that the process is immunologically mediated by thyroid-specific circulating components in the absence of normal immune regulatory function. Images Fig. 1 Fig. 3 Fig. 4 PMID:6896018

  7. The association with Turner syndrome significantly affects the course of Hashimoto's thyroiditis in children, irrespective of karyotype.

    PubMed

    Aversa, Tommaso; Messina, Maria Francesca; Mazzanti, Laura; Salerno, Mariacarolina; Mussa, Alessandro; Faienza, Maria Felicia; Scarano, Emanuela; De Luca, Filippo; Wasniewska, Malgorzata

    2015-12-01

    Only few studies have investigated to now whether the association with Turner syndrome (TS) may affect the course of Hashimoto's thyroiditis (HT) in children. Aim of this study was to ascertain whether the presentation and long-term course of HT in TS children may be characterized by a peculiar and atypical pattern. The clinical and biochemical findings at HT diagnosis in 90 TS children (group A) were compared with those recorded in 449 girls with HT but without TS (group B); in group A patients, thyroid function tests were re-evaluated after a median time interval of 4.9 years. At HT diagnosis median TSH levels and the rate of cases presenting with a thyroid dysfunction picture were significantly lower in group A, irrespective of karyotype abnormalities. In group A only 34.8 % of the girls who had initially presented with euthyroidism remained euthyroid even at re-evaluation, whilst 67.7 % of those who had presented with subclinical hypothyroidism became overtly hypothyroid over time; also such evolutive pattern was irrespective of karyotype abnormalities. (1) In TS girls, HT presents with a milder hormonal pattern, which often deteriorates over time; (2) these biochemical features are not necessarily linked with a specific karyotype.

  8. Thyroid function and stress hormones in children with stress hyperglycemia.

    PubMed

    Bordbar, Mohammad Reza; Taj-Aldini, Reza; Karamizadeh, Zohre; Haghpanah, Sezaneh; Karimi, Mehran; Omrani, Gholam Hossein

    2012-12-01

    The purpose of the study is to determine the prevalence of stress hyperglycemia and to investigate how thyroid and stress hormones alter during stress hyperglycemia in children admitted to pediatric emergency wards. A prospective cross-sectional study was conducted in children, less than 19 years old, who were admitted to pediatric emergency wards of Nemazee and Dastgheib Hospitals, Shiraz, Southern Iran. Those patients taking steroids, beta-agonists or intravenously administered glucose before venipuncture, and patients with diabetes mellitus (DM) or thyroid diseases were excluded. Children with blood glucose ≥ 150 mg/dL during admission were regarded as cases. The controls were age- and- sex- matched, euglycemic children. Stress hormones including cortisol, insulin, growth hormone, and prolactin were measured, and thyroid function was tested with a radioimmunoassay (RIA) method in all cases and controls. The results showed that among 1,054 screened children, 39 cases (3.7 %) had stress hyperglycemia and 89 controls were included in the study. The occurrence of hyperglycemia was independent of sex, but it occurred mostly in children under 6 years old. Hyperglycemia occurred more frequently in patients with a positive family history of DM (odds ratio = 3.2, 95 % CI = 1.3-7.9, and P = 0.009). There were no significant differences between cases and controls regarding any hormones except higher cortisol, and lower total T3 and T4 in cases compared with controls. Neither of cases developed diabetes in the 24-month follow-up period. These findings led us to the conclusion that stress hyperglycemia is occasionally seen in critically ill patients. Among the stress hormones measured, only cortisol increased during hyperglycemia. It seems that hyperglycemia is not an important risk factor for future diabetes.

  9. Effects of amiodarone on thyroid function in humans

    SciTech Connect

    Zaninovich, A.A.; Bosco, S.; Contreras, L.; El Tamer, E.; Chiozza, M.; Fernandez Pol, J.A.

    1985-05-01

    The present work studies the effects of the anti-arrhythmic drug amiodarone on thyroidal release slopes (TRS) and peripheral kinetics of /sup 125/I-thyroxine (/sup 125/I-T/sub 4/) and /sup 125/I-triiodothyronine (/sup 125/I-T/sub 3/) during chronic (200-800 mg/day, 2-5 years) or acute (400 mg/day, 5-8 days) treatment with amiodarone. Each patient received a tracer does of /sup 125/I-T/sub 4/ or /sup 125/I-T/sub 3/ iv. TRS were derived from daily plasma ratios of /sup 127/I-T4//sup 125/I-T4 and /sup 127/I-T3//sup 125/I-T3. Double antibody radioimmunoassay techniques were employed to measure serum T4, T3, reverse T3 and thyrotropin (TSH). In the /sup 125/I-T4 studies, 8 chronically-treated patients had a mean TRS value of 0.063 +- 0.033 (SD) versus 0.110 +- 0.030 in controls (NS). Fractional T4 turnover (k) was 70% metabolic clearance rate (MCR) 80% and disposal rate (DS) 79% (NS) of the respective value in control subjects. The acute studies in 5 normal subjects showed no changes with amiodarone. In the /sup 125/I-T3 studies chronic patients had a decreased TRS, k MCR and DR whereas the acute studies showed similar, significant changes during amiodarone treatment. Serum T4 and reverse T3 were significantly elevated serum T3 was decreased and serum TSH was non-significantly increased. The authors conclude that despite the supranormal serum T4 and TSH, amiodarone appeared to depress thyroidal function and to block the thyroid gland response to a peripheral decrease in T4 conversion to T3.

  10. 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

  11. Sperm function in affective illness.

    PubMed

    Amsterdam, J; Winokur, A; Levin, R

    1981-04-01

    There is evidence for functional changes in the hypothalamic-pituitary-gonadal axis of patients with affective disorders. Little is known concerning spermatogenesis or sperm function in depressed men. We systematically evaluated the sperm indices in a group of depressed males complaining of diminished libido, and a healthy control group. No differences were noted in sperm parameters between the groups.

  12. Thyroid function 48h after delivery as a marker for subsequent postpartum depression.

    PubMed

    Albacar, Glòria; Sans, Teresa; Martín-Santos, Rocío; García-Esteve, Lluïsa; Guillamat, Roser; Sanjuan, Julio; Cañellas, Francesca; Carot, José Miguel; Gratacòs, Mònica; Bosch, Joan; Gaviria, Ana; Labad, Antonio; Zotes, Alfonso Gutiérrez; Vilella, Elisabet

    2010-06-01

    Physiological changes during gestation and after delivery are associated with postpartum thyroid dysfunction, which is due to thyroid autoimmunity in some cases. Postpartum thyroid dysfunction, in turn, has been associated with postpartum depression (PPD). The aim of the present study was to evaluate whether thyroid function immediately after delivery can predict postpartum depression at 8 weeks and 32 weeks after delivery. This study examined 1053 postpartum Spanish women without a previous history of depression. We evaluated depressive symptoms at 48h, 8 weeks and 32 weeks postpartum and used a diagnostic interview to confirm major depression for all probable cases. Free thyroxin (fT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibodies (TPOAb) and C-reactive protein (CRP) were assayed at 48h postpartum. Binary and multivariate logistic regression analyses were performed to determine independent risk factors for PPD. Although 152 women (14.4%) had high TPOAb (>27IU/mL) and slightly elevated TSH concentrations with normal fT4, we did not find any association between thyroid function and PPD. This thyroid dysfunction was not associated with CRP concentrations that were outside of the normal range (>3mg/L). We conclude that thyroid function at 48h after delivery does not predict PPD susceptibility. PMID:19939574

  13. Thyroid function and metabolic state in chronic renal failure.

    PubMed

    Spector, D A; Davis, P J; Helderman, J H; Bell, B; Utiger, R D

    1976-12-01

    Thirty-eight patients with chronic renal insufficiency who were in a dialysis program underwent studies of thyroid function and metabolic status. Mean values for serum total and free thyroxine (T4) concentrations and thyroxine-binding globulin capacity were within normal limits. Although mean serum total triiodothyronine (T3) concentration was normal, 43% of the group had low serum T3 and 54% had low serum free T3 concentrations. Serum thyrotrophin (TSH) concentrations were normal in all but four subjects who had very slight elevations. Metabolic status was assessed by various metabolic tests; mean values for each of these tests were normal, and the clinical index scores indicated that all patients were euthyroid. Results of metabolic testing were similar in patients with low and those with normal serum T3 concentrations. Low serum T3 measurements did not accurately reflect metabolic state in patients with chronic renal failure, whereas serum free T4 and TSH concentrations were reliable indicators of thyroid state.

  14. Evaluation of strategy for testing thyroid function applied to hypothyroidism.

    PubMed Central

    Corns, C M; Miller, A L

    1986-01-01

    A strategy for testing thyroid function with discretionary assay of thyroid stimulating hormone (TSH) following initial measurement of total plasma thyroxine (tT4) was retrospectively evaluated in relation to the diagnosis of primary hypothyroidism. Over a two year period 14 641 tT4 assays were done and 6887 TSH assays, of which 29% were initiated in the laboratory. The percentage of raised TSH values (over 5 mU/1) was similar to those for clinician and pathologist initiated requests (23.2% and 23.6%). Some TSH requests (1620) were cancelled; when 212 of these were subsequently analysed the TSH value was raised in 5.7% The incidence of raised TSH values in 188 patients with a tT4 below 100 nmol/1 (7.8 micrograms/100 ml), in whom TSH was not requested, was 5.3% Most of these raised TSH results could be readily explained by information available to the requesting clinician but not given on the request form. PMID:3082940

  15. Risk assessment of thyroid follicular cell tumors.

    PubMed Central

    Hill, R N; Crisp, T M; Hurley, P M; Rosenthal, S L; Singh, D V

    1998-01-01

    Thyroid follicular cell tumors arise in rodents from mutations, perturbations of thyroid and pituitary hormone status with increased stimulation of thyroid cell growth by thyroid-stimulating hormone (TSH), or a combination of the two. The only known human thyroid carcinogen is ionizing radiation. It is not known for certain whether chemicals that affect thyroid cell growth lead to human thyroid cancer. The U.S. Environmental Protection Agency applies the following science policy positions: 1) chemically induced rodent thyroid tumors are presumed to be relevant to humans; 2) when interspecies information is lacking, the default is to assume comparable carcinogenic sensitivity in rodents and humans; 3) adverse rodent noncancer thyroid effects due to chemically induced thyroid-pituitary disruption are presumed to be relevant to humans; 4) linear dose-response considerations are applied to thyroid cancer induced by chemical substances that either do not disrupt thyroid functioning or lack mode of action information; 5) nonlinear thyroid cancer dose-response considerations are applied to chemicals that reduce thyroid hormone levels, increase TSH and thyroid cell division, and are judged to lack mutagenic activity; and 6) nonlinear considerations may be applied in thyroid cancer dose-response assessments on a case-by-case basis for chemicals that disrupt thyroid-pituitary functioning and demonstrate some mutagenic activity. Required data for risk assessment purposes is mode of action information on mutagenicity, increases in follicular cell growth (cell size and number) and thyroid gland weight, thyroid-pituitary hormones, site of action, correlations between doses producing thyroid effects and cancer, and reversibility of effects when dosing ceases. Images Figure 1 Figure 2 Figure 3 PMID:9681971

  16. Thyroid function after radiotherapy and laryngectomy for carcinoma of the larynx

    SciTech Connect

    Palmer, B.V.; Gaggar, N.; Shaw, H.J.

    1981-01-01

    Total levels of thyroxine (T4) and thyroid-stimulating hormone (TSH) were measured in 37 patients who had previously had carcinoma of the larynx treated by radiotherapy and total laryngectomy with thyroid lobectomy. Ten percent of the patients had clinical features of hypothyroidism and 30% had total T4 levels below the lower limit of normal. A further 40% had results in the low normal range. Forty-four percent of patients had raised TSH levels, 90% of these having low or low normal T4 levels. The histology of the thyroid gland was normal in all 37 patients. Attention should be given to preserving intact the vasculature of the contralateral thyroid lobe whenever it is necessary to remove the ipsilateral thyroid lobe during a laryngectomy. Proper postoperative assessment of thyroid gland function is desirable in all these patients to identify those at risk of hypothyroidism and to avoid unnecessary morbidity.

  17. Autoimmunity affects health-related quality of life in patients with Hashimoto's thyroiditis.

    PubMed

    Bektas Uysal, Hilal; Ayhan, Mediha

    2016-08-01

    Hashimoto's thyroiditis (HT) is the most common endocrine disorder leading to hypothyroidism. HT is characterized by the presence of elevated circulating antibodies, especially anti-thyroid peroxidase (anti-TPO) and anti-thyroglobulin (anti-Tg). In our study, we aimed to reveal the effects of autoimmunity on health-related quality of life of euthyroid HT patients. Patients who were admitted to the Adnan Menderes University Outpatient Clinic were enrolled. The medical records of the patients were surveyed and their demographical data were collected. By using communication data, the patients were invited to our clinic, to inform them about our study and to fill out the health-related quality of life questionnaire. A total of 84 euthyroid HT patients older than 18 years who completed the short form-36 questionnaire, were enrolled. As all patients were euthyroid, there was a significant negative correlation between each domain score and the antibody levels, individually. Patients who had higher anti-TPO and anti-Tg levels had significantly lower quality of life domain scores (p < 0.001). There was statistically no significant correlation between the antibody levels and thyroid function tests (p > 0.05). Additionally, all dimension scores were significantly higher both in the anti-Tg and anti-TPO negative groups, indicating a better quality of life than that in the antibody positive groups. Our study revealed that higher thyroid antibody levels were negatively correlated with life quality scores. Thus, patients who had higher anti-TPO and anti-Tg levels had significantly lower quality of life domain scores. We believe that apart from hypothyroidism, a high antibody level was one of the contributing factors for the development of HT-associated symptoms, leading to a lower quality of life. Other probable contributing factors such as selenium deficiency, thyroid hormone fluctuation, and disease awareness should keep in mind. PMID:27523457

  18. Premature twins of a mother with Graves' disease with discordant thyroid function: a case report.

    PubMed

    O'Connor, M J; Paget-Brown, A O; Clarke, W L

    2007-06-01

    Thyroid dysfunction is recognized in the newborns of mothers affected by Graves' disease during pregnancy. We describe the development of concurrent hyperthyroidism and hypothyroidism in the twin infants of a mother with Graves' disease diagnosed during pregnancy.

  19. [Characterization of thyroglobulin in a patient with functioning and non-functioning benign thyroid tumors].

    PubMed

    Ishikita, T; Iino, Y; Ishida, T; Takei, H; Morishita, Y; Tarutani, O

    1992-08-20

    The chemical and immunological properties of thyroglobulin (Tg) in tissue obtained from a patient co-existed with two types of thyroid tumors, i.e., functioning and non-functioning, and were compared with the properties of Tg that was isolated from adjacent peripheral tissue. In the present observations, the Tg content was markedly increased in the non-functioning thyroid tumor. On the other hand, the Tg content in the functioning tumor was at the normal level. The iodine content of Tg was significantly lower in the non-functioning tumor than in peripheral tissues. Affinity with Lectins differed among Tg preparations, suggesting that the carbohydrate chain in the Tg was different in each nodule in a single individual.

  20. Thyrocyte-specific Gq/G11 deficiency impairs thyroid function and prevents goiter development.

    PubMed

    Kero, Jukka; Ahmed, Kashan; Wettschureck, Nina; Tunaru, Sorin; Wintermantel, Tim; Greiner, Erich; Schütz, Günther; Offermanns, Stefan

    2007-09-01

    The function of the adult thyroid is regulated by thyroid-stimulating hormone (TSH), which acts through a G protein-coupled receptor. Overactivation of the TSH receptor results in hyperthyroidism and goiter. The Gs-mediated stimulation of adenylyl cyclase-dependent cAMP formation has been regarded as the principal intracellular signaling mechanism mediating the action of TSH. Here we show that the Gq/G11-mediated signaling pathway plays an unexpected and essential role in the regulation of thyroid function. Mice lacking the alpha subunits of Gq and G11 specifically in thyroid epithelial cells showed severely reduced iodine organification and thyroid hormone secretion in response to TSH, and many developed hypothyroidism within months after birth. In addition, thyrocyte-specific Galphaq/Galpha11-deficient mice lacked the normal proliferative thyroid response to TSH or goitrogenic diet, indicating an essential role of this pathway in the adaptive growth of the thyroid gland. Our data suggest that Gq/G11 and their downstream effectors are promising targets to interfere with increased thyroid function and growth.

  1. High-resolution genomic profiling of thyroid lesions uncovers preferential copy number gains affecting mitochondrial biogenesis loci in the oncocytic variants

    PubMed Central

    Kurelac, Ivana; de Biase, Dario; Calabrese, Claudia; Ceccarelli, Claudio; Ng, Charlotte KY; Lim, Raymond; MacKay, Alan; Weigelt, Britta; Porcelli, Anna Maria; Reis-Filho, Jorge S; Tallini, Giovanni; Gasparre, Giuseppe

    2015-01-01

    Oncocytic change is the result of aberrant mitochondrial hyperplasia, which may occur in both neoplastic and non-neoplastic cells and is not infrequent in the thyroid. Despite being a well-characterized histologic phenotype, the molecular causes underlying such a distinctive cellular change are poorly understood. To identify potential genetic causes for the oncocytic phenotype in thyroid, we analyzed copy number alterations in a set of oncocytic (n=21) and non-oncocytic (n=20) thyroid lesions by high-resolution microarray-based comparative genomic hybridization (aCGH). Each group comprised lesions of diverse histologic types, including hyperplastic nodules, adenomas and carcinomas. Unsupervised hierarchical clustering of categorical aCGH data resulted in two distinct branches, one of which was significantly enriched for samples with the oncocytic phenotype, regardless of histologic type. Analysis of aCGH events showed that the oncocytic group harbored a significantly higher number of genes involved in copy number gains, when compared to that of conventional thyroid lesions. Functional annotation demonstrated an enrichment for copy number gains that affect genes encoding activators of mitochondrial biogenesis in oncocytic cases but not in their non-oncocytic counterparts. Taken together, our data suggest that genomic alterations may represent additional/alternative mechanisms underlying the development of the oncocytic phenotype in the thyroid. PMID:26269756

  2. Global expression profiling reveals gain-of-function onco-genic activity of a mutated thyroid hormone receptor in thyroid carcinogenesis

    PubMed Central

    Lu, Changxue; Mishra, Alok; Zhu, Yuelin J; Meltzer, Paul; Cheng, Sheue-yann

    2011-01-01

    Thyroid hormone receptors (TRs) are critical in regulating gene expression in normal physiological processes. Decreased expression and/or somatic mutations of TRs have been shown to be associated several types of human cancers including liver, breast, lung, and thyroid. To understand the molecular mechanisms by which mutated TRs promote carcinogenesis, an animal model of follicular thyroid carcinoma (FTC) (Thrbpv/pv mice) was used in the present study. The Thrbpv/pv mouse harbors a knockin dominant negative PV mutation, identified in a patient with resistance to thyroid hormone. To understand whether oncogenic actions of PV involve not only the loss of normal TR functions but also gain-of-function activities, we compared the gene expression profiles of thyroid lesions in Thrbpv/pv mice and Thra1-/- Thrb-/- mice that also spontaneously develop FTC, but with less severe malignancy. Analysis of the cDNA microarray data derived from microdissected thyroid tumor cells of these two mice showed contrasting global gene expression profiles. With stringent selection using 2.5-fold change (p<0.01) in cDNA microarray analysis, 241 genes with altered gene expression were identified. Nearly half of the genes (n=103: 42.7% of total) with altered gene expression in thyroid tumor cells of Thrbpv/pv mice were associated with tumorigenesis and metastasis; some of these genes function as oncogenes in human thyroid cancers. The remaining genes were found to function in transcriptional regulation, RNA processing, cell proliferation, apoptosis, angiogenesis, and cytoskeleton modification. These results indicate that the more aggressive thyroid tumor progression in Thrbpv/pv mice was not due simply to the loss of tumor suppressor functions of TR via mutation but also, importantly, to gain-of-function in the oncogenic activities of PV to drive thyroid carcinogenesis. Thus, the present study identifies a novel mechanism by which a mutated TRβ evolves with an oncogenic advantage to promote

  3. Relationship of dietary iodide and drinking water disinfectants to thyroid function in experimental animals

    SciTech Connect

    Revis, N.W.; McCauley, P.; Holdsworth, G.

    1986-11-01

    The importance of dietary iodide on the reported hypothyroid effect of drinking water disinfectants on thyroid function was investigated. Previous studies have also showed differences in the relative sensitivity of pigeons and rabbits to chlorinated water. Pigeons and rabbits were exposed for 3 months to diets containing high (950 ppb) or low (300 ppb) levels of iodide and to drinking water containing two levels of chlorine. Results showed that the high-iodide diet prevented the hypothyroid effect observed in pigeons given the low-iodide diet and chlorinated drinking water. Similar trends were observed in rabbits exposed to the same treatment; however, significant hypothyroid effects were not observed in this animal model. The factor associated with the observed effect of dietary iodide on the chlorine-induced change in thyroid function is unknown, as is the relative sensitivity of rabbits and pigeons to the effect of chlorine. Several factors may explain the importance of dietary iodide and the relative sensitivity of these species. For example, the iodine formed by the known reaction of chlorine with iodide could result in a decrease in the plasma level of iodide because of the relative absorption rates of iodide and iodine in the intestinal tract, and the various types and concentrations of chloroorganics (metabolites) formed in the diet following the exposure of various dietary constituents to chlorine could affect the thyroid function. The former factor was investigated in the present studies. Results do not confirm a consistent, significant reduction in the plasma level of iodide in rabbits and pigeons exposed to chlorinated water and the low-iodide diet. The latter factor is being investigated.

  4. A loss-of-function genetic screening identifies novel mediators of thyroid cancer cell viability.

    PubMed

    Cantisani, Maria Carmela; Parascandolo, Alessia; Perälä, Merja; Allocca, Chiara; Fey, Vidal; Sahlberg, Niko; Merolla, Francesco; Basolo, Fulvio; Laukkanen, Mikko O; Kallioniemi, Olli Pekka; Santoro, Massimo; Castellone, Maria Domenica

    2016-05-10

    RET, BRAF and other protein kinases have been identified as major molecular players in thyroid cancer. To identify novel kinases required for the viability of thyroid carcinoma cells, we performed a RNA interference screening in the RET/PTC1(CCDC6-RET)-positive papillary thyroid cancer cell line TPC1 using a library of synthetic small interfering RNAs (siRNAs) targeting the human kinome and related proteins. We identified 14 hits whose silencing was able to significantly reduce the viability and the proliferation of TPC1 cells; most of them were active also in BRAF-mutant BCPAP (papillary thyroid cancer) and 8505C (anaplastic thyroid cancer) and in RAS-mutant CAL62 (anaplastic thyroid cancer) cells. These included members of EPH receptor tyrosine kinase family as well as SRC and MAPK (mitogen activated protein kinases) families. Importantly, silencing of the identified hits did not affect significantly the viability of Nthy-ori 3-1 (hereafter referred to as NTHY) cells derived from normal thyroid tissue, suggesting cancer cell specificity. The identified proteins are worth exploring as potential novel druggable thyroid cancer targets. PMID:27058903

  5. A loss-of-function genetic screening identifies novel mediators of thyroid cancer cell viability

    PubMed Central

    Cantisani, Maria Carmela; Parascandolo, Alessia; Perälä, Merja; Allocca, Chiara; Fey, Vidal; Sahlberg, Niko; Merolla, Francesco; Basolo, Fulvio; Laukkanen, Mikko O.; Kallioniemi, Olli Pekka; Santoro, Massimo; Castellone, Maria Domenica

    2016-01-01

    RET, BRAF and other protein kinases have been identified as major molecular players in thyroid cancer. To identify novel kinases required for the viability of thyroid carcinoma cells, we performed a RNA interference screening in the RET/PTC1(CCDC6-RET)-positive papillary thyroid cancer cell line TPC1 using a library of synthetic small interfering RNAs (siRNAs) targeting the human kinome and related proteins. We identified 14 hits whose silencing was able to significantly reduce the viability and the proliferation of TPC1 cells; most of them were active also in BRAF-mutant BCPAP (papillary thyroid cancer) and 8505C (anaplastic thyroid cancer) and in RAS-mutant CAL62 (anaplastic thyroid cancer) cells. These included members of EPH receptor tyrosine kinase family as well as SRC and MAPK (mitogen activated protein kinases) families. Importantly, silencing of the identified hits did not affect significantly the viability of Nthy-ori 3-1 (hereafter referred to as NTHY) cells derived from normal thyroid tissue, suggesting cancer cell specificity. The identified proteins are worth exploring as potential novel druggable thyroid cancer targets. PMID:27058903

  6. Testosterone and estradiol treatments differently affect pituitary-thyroid axis and liver deiodinase 1 activity in orchidectomized middle-aged rats.

    PubMed

    Šošić-Jurjević, B; Filipović, B; Renko, K; Miler, M; Trifunović, S; Ajdžanovič, V; Kӧhrle, J; Milošević, V

    2015-12-01

    We previously reported that orchidectomy (Orx) of middle-aged rats (15-16-month-old; MA) slightly affected pituitary-thyroid axis, but decreased liver deiodinase (Dio) type 1 and pituitary Dio2 enzyme activities. At present, we examined the effects of subsequent testosterone-propionate treatment (5mg/kg; Orx+T), and compared the effects of testosterone with the effects of estradiol-dipropionate (0.06mg/kg; Orx+E) treatment. Hormones were subcutaneously administered, daily, for three weeks, while Orx and sham-operated (SO) controls received only the vehicle. The applied dose of T did not alter serum TSH, T4 and T3 concentrations in Orx- MA, though it increased TSH when administrated to Orx young adults (2.5-month-old; Orx-YA). However, pituitaries of Orx-MA+T rats had higher relative intensity of immunofluorescence (RIF) for TSHβ; in their thyroids we found increased volume and height of follicular epithelium, decreased volume of the colloid and higher RIF for T4-bound to thyroglobulin (Tg-T4). Liver Dio1 activity was increased. E-treatment did not affect serum hormone levels, pituitary RIF for TSHβ, or liver Dio1 activity in Orx-MA rats. Thyroids had decreased relative volume and height of follicular epithelium, increased relative volume of the colloid, decreased volume of sodium-iodide symporter-immunopositive epithelium and lower RIF for Tg-T4. Detected changes were statistically significant. In conclusion, androgenization enhanced pituitary TSHβ RIF, thyroid activation and liver Dio1 enzyme activity in Orx-MA, without elevating serum TSH as in Orx-YA rats. Estrogenization induced pituitary enlargement with no effect on pituitary TSHβ RIF, serum TSH or liver Dio1 activity. E also induced alterations in thyroid histology that indicate mild suppression of its functioning, and contributed to thyroid blood vessel enlargement in Orx-MA rats. PMID:26384168

  7. The synthetic gestagen levonorgestrel directly affects gene expression in thyroid and pituitary glands of Xenopus laevis tadpoles.

    PubMed

    Lorenz, Claudia; Opitz, Robert; Trubiroha, Achim; Lutz, Ilka; Zikova, Andrea; Kloas, Werner

    2016-08-01

    The synthetic gestagen levonorgestrel (LNG) was previously shown to perturb thyroid hormone-dependent metamorphosis in Xenopus laevis. However, so far the mechanisms underlying the anti-metamorphic effects of LNG remained unknown. Therefore, a series of in vivo and ex vivo experiments was performed to identify potential target sites of LNG action along the pituitary-thyroid axis of X. laevis tadpoles. Prometamorphic tadpoles were treated in vivo with LNG (0.01-10nM) for 72h and brain-pituitary and thyroid tissue was analyzed for marker gene expression. While no treatment-related changes were observed in brain-pituitary tissue, LNG treatment readily affected thyroidal gene expression in tadpoles including decreased slc5a5 and iyd mRNA expression and a strong induction of dio2 and dio3 expression. When using an ex vivo organ explant culture approach, direct effects of LNG on both pituitary and thyroid gland gene expression were detecTable Specifically, treatment of pituitary explants with 10nM LNG strongly stimulated dio2 expression and concurrently suppressed tshb expression. In thyroid glands, ex vivo LNG treatment induced dio2 and dio3 mRNA expression in a thyrotropin-independent manner. When thyroid explants were cultured in thyrotropin-containing media, LNG caused similar gene expression changes as seen after 72h in vivo treatment including a very strong repression of thyrotropin-induced slc5a5 expression. Concerning the anti-thyroidal activity of LNG as seen under in vivo conditions, our ex vivo data provide clear evidence that LNG directly affects expression of genes important for thyroidal iodide handling as well as genes involved in negative feedback regulation of pituitary tshb expression. PMID:27262936

  8. Morphological and functional changes in the thyroid gland of methyl thiophanate-injected lizards, Podarcis sicula.

    PubMed

    Sciarrillo, Rosaria; De Falco, Maria; Virgilio, Francesca; Laforgia, Vincenza; Capaldo, Anna; Gay, Flaminia; Valiante, Salvatore; Varano, Lorenzo

    2008-08-01

    The thyroid has been shown to be a target organ for environmental chemicals, specifically endocrine-disrupting contaminants. Reptiles are particularly suitable as contaminant biomonitors due to their persistence in a variety of habitats, wide geographic distribution, longevity, and, in many cases, site fidelity. Methyl thiophanate is a systemic broad-spectrum fungicide used to prevent and control plant diseases caused by various fungi. The aim of this study was to develop an integrated biological model for monitoring the ecotoxic effects of thiophanate-methyl fungicide on the thyroid of the lizard Podarcis sicula. The results of this study indicate that both structural and functional differences in the thyroid gland of the lizard exist in the animals exposed to methyl thiophanate. Structurally, animals exposed to methyl thiophanate showed decreased epithelial cell height; the nuclei of the thyroid cells were small and elongated with dense chromatin and a greatly reduced cytoplasm. The colloid was retracted with few reabsorption vacuoles. Functionally, the same animals exhibited decreased T4 and T3 plasma levels compared to control animals. Methyl thiophanate administration produced statistically significant inhibition on serum thyroid-stimulating hormone levels and this is the mechanism for altering thyroid function. This study highlights how thyroid gland disruption, both structural and functional, in lizard and other nontarget organisms might also have an environmental aetiology.

  9. 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...

  10. 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

  11. Thyroid diseases in elderly.

    PubMed

    Faggiano, A; Del Prete, M; Marciello, F; Marotta, V; Ramundo, V; Colao, A

    2011-09-01

    Thyroid diseases are the commonest endocrine disorders in the general population. In most of the cases, they are consistent with benign conditions which may be asymptomatic or affect people at a variable extent. Since they often represent chronic conditions their prevalence increases by age and reaches in elderly the highest rates. Thyroid nodules are a common clinical finding. Most subjects with thyroid nodules have few or no symptoms. Thyroid nodules are more commonly non-functioning. However, in elderly, toxic multinodular goiter is the most frequent cause of spontaneous hyperthyroidism and often, it emerges insidiously from nontoxic multinodular goiter. Although autoimmune thyroiditis is the most common cause of hypothyroidism in elderly subjects, other causes, such as drugs, neck radiotherapy, thyroidectomy or radioiodine therapy, are frequently observed among these subjects. A small subset of medications including dopamine agonists, glucocorticoids and somatostatin analogs affect thyroid function through suppression of TSH. Other medications that may affect TSH levels are metformin, antiepileptic medications, lithium carbonate and iodine-containing medications. Other drugs can alter T4 absorption, T4 and T3 transport in serum and metabolism of T4 and T3, such as proton-pump inhibitors and antacids, estrogens, mitotane and fluorouracil, phenobarbital and rifampin. Amiodarone administration is associated with thyrotoxicosis or hypothyroidism. Thyroid cancer has similar characteristics in elderly as in general population, however the rate of aggressive forms such as the anaplastic histotype, is higher in older than younger subjects. Diagnosis of thyroid diseases includes a comprehensive medical history and physical examination and appropriate laboratory tests. A correct diagnosis of thyroid diseases in the elderly is crucial for proper treatment, which consists in the removal of medications that may alter thyroid function, in the use of levo-thyroxine in case of

  12. Exposure to Lithium and Cesium Through Drinking Water and Thyroid Function During Pregnancy: A Prospective Cohort Study

    PubMed Central

    Harari, Florencia; Bottai, Matteo; Casimiro, Esperanza; Palm, Brita

    2015-01-01

    Background: Impaired thyroid function is a common side effect of lithium medication. Recent data indicate that lithium exposure through drinking water, although providing much lower doses than the medication, may also affect thyroid hormone levels. However, the effects in susceptible groups like pregnant women are not known. Methods: In a population-based mother–child cohort in the Argentinean Andes (n = 194), an area with varying concentrations of lithium in the drinking water, we assessed lithium exposure repeatedly during pregnancy by measuring the concentrations in blood using inductively coupled plasma mass spectrometry. The markers of thyroid function included thyrotropin (TSH), free/total thyroxine (fT4/T4), free/total triiodothyronine (fT3/T3), thyroglobulin, and transthyretin in serum, sampled at the same time. Multiple potential confounders, including exposure to arsenic, cesium, and boron (elevated in water) as well as selenium and iodine (essential for thyroid function) were considered. Results: The lithium concentrations in blood [median 25 μg/L (0.0036 mmol/L); range 1.9–145 μg/L (0.000027–0.021 mmol/L)] correlated significantly with those in urine and drinking water (rs = 0.84, p < 0.001, and rs = 0.40, p < 0.001, respectively). Using linear quantile regression models, we found a positive association between blood lithium (log2 transformed) and TSH concentrations, particularly in the lowest percentiles of TSH (B = 0.20 mIU/L, [95% confidence interval 0.048–0.35] at the fifth percentile). We also found inverse associations of blood lithium with transthyretin, particularly at the highest percentiles, as well as with fT3 and T3, with less obvious variation across percentiles. Unexpectedly, blood cesium concentrations (median 111 μg/L, range 2.5–711 μg/L) were also inversely associated with fT3 and T3, particularly at the highest T3 percentiles, but not with TSH or transthyretin. Arsenic and boron

  13. Evaluation of Thyroid Disorders During Head-and-Neck Radiotherapy by Using Functional Analysis and Ultrasonography

    SciTech Connect

    Bakhshandeh, Mohsen; Hashemi, Bijan; Mahdavi, Seyed Rabie; Nikoofar, Alireza; Edraki, Hamid Reza; Kazemnejad, Anoshirvan

    2012-05-01

    Purpose: To evaluate thyroid function and vascular changes during radiotherapy for patients with head and neck cancer. Methods and Materials: Fifty patients treated with primary or postoperative radiotherapy for various cancers in the head and neck region were prospectively evaluated. The serum samples (triiodothyronine [T3], thyroxine [T4], thyroid-stimulating hormone [TSH], free triiodothyronine [FT3], and free thyroxine [FT4]), the echo level of the thyroid gland, and color Doppler ultrasonography (CDU) parameters of the right inferior thyroid artery (RITA) of the patients were measured before and at regular intervals during radiotherapy. The thyroid gland dose-volume histograms of the patients were derived from their computed tomography-based treatment plans. Results: There was a significant fall in TSH level (p < 0.0001) but an increase in FT4 (p < 0.0001) and T4 (p < 0.022) levels during the radiotherapy course. The threshold dose required to produce significant changes was 12 Gy (Biologically Effective Dose in 2-Gy fractions, BED{sub 2}). There were significant rises in the patients' pulsatility index, resistive index, peak systolic velocity, blood volume flow levels, and RITA diameter (p < 0.0001), as detected by CDU during radiotherapy, compared to those parameters measured before the treatment. Hypoechogenicity and irregular echo patterns (p < 0.0001) were seen during radiotherapy compared to those before treatment. There was significant Pearson's correlation between the CDU parameters and T4, FT4, and TSH levels. Conclusions: Radiation-induced thyroiditis is regarded as primary damage to the thyroid gland. Thyroiditis can subsequently result in hypothyroidism or hyperthyroidism. Our results demonstrated that changes in thyroid vessels occur during radiotherapy delivered to patients. Vessel changes also can be attributed to the late effect of radiation on the thyroid gland. The hypoechogenicity and irregular echo patterns observed in patients may result

  14. Interaction of selenium and lead on several aspects of thyroid function in Pekin ducklings

    SciTech Connect

    Goldman, M.; Dillon, R.D.

    1982-09-01

    Lead shot recovered at necropsy 2 and 3 weeks after being dropped down the throats of Pekin ducklings caused significant increases in thyroid gland weight and 24-hr thyroid uptake of /sup 125/I while serum PB/sup 125/I levels were maintained at or above control values. Supplementation of lead shot with 1 ppm selenium in drinking water reduced these increases. Selenium in the drinking water incurred no increase in thyroid gland weight at 2 weeks but some goitrogenicity at 3 weeks and significant reductions in thyroid radioiodine uptake and serum PB/sup 125/I levels at 2 and 3 weeks. Chromatographic analyses of thyroid hydrolysates demonstrated a depression in iodothyronine (T4 and T3) labeling in lead shot-treated and selenium-treated animals which was corrected by addition of selenium to lead shot-treated ducklings. These findings indicate that while either lead or selenium treatment, independently, exerts a selective toxic effect on thyroid function, selenium supplementation of lead-treated Pekin ducklings does protect against the toxicity of lead on thyroid function.

  15. Chemical contamination and the thyroid.

    PubMed

    Duntas, Leonidas H

    2015-02-01

    Industrial chemical contaminants have a variable impact on the hypothalamic-pituitary-thyroid axis, this depending both on their class and on confounding factors. Today, mounting evidence is pointing to the role of environmental factors, and specifically EDCs, in the current distressing upsurge in the incidence of thyroid disease. The unease is warranted. These substances, which are nowadays rife in our environments (including in foodstuffs), have been shown to interfere with thyroid hormone action, biosynthesis, and metabolism, resulting in disruption of tissue homeostasis and/or thyroid function. Importantly, based on the concept of the "nonmonotonic dose-response curve", the relationship between dose and effect has often been found to be nonlinear. Thus, small doses can induce unpredictable, adverse effects, one case being polychlorinated biphenyls (PCBs), of which congener(s) may centrally inhibit the hypothalamic-pituitary-thyroid axis, or dissociate thyroid receptor and selectively affect thyroid hormone signaling and action. This means that PCBs can act as agonists or antagonists at the receptor level, underlining the complexity of the interaction. This review highlights the multifold activity of chemicals demonstrated to cause thyroid disruption. It also represents a call to action among clinicians to undertake systematic monitoring of thyroid function and registering of the classes of EDs and additionally urges broader scientific collaborations to clarify these chemicals' molecular mechanisms of action, substances whose prevalence in our environments is disrupting not only the thyroid but all life on earth. PMID:25294013

  16. 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.

  17. Optimum laboratory test combinations for thyroid function studies, selected by discriminant analysis.

    PubMed

    Rootwelt, K; Solberg, H E

    1978-09-01

    In 430 patients with a variety of thyroid disorders, linear discriminant analysis was used to select laboratory test combinations giving optimum diagnostic efficiency in thyroid function studies. Unexpectedly, TSH was found valuable in the diagnosis of hyperthyroidism and T3 in hypothyroidism. These test combinations were found optimal for the separation of euthyroidism/hyperthyroidism: T3, TSH and T4; euthyroidism/hypothyroidism: Combined free thyroid hormone index (FTI) and TSH; and hyperthyroidism/euthyroidism/hypothyroidism: T3, TSH, T4, FTI and T3U. The latter test combination had a total efficiency of 94%. Cholesterol, achilles reflex time, PBI and radioiodine uptake measurement contributed little to the discrimination.

  18. [Pregnancy and the thyroid gland].

    PubMed

    Schlienger, J L; Dreyfus, M

    1993-01-01

    During pregnancy the thyroid should adapt itself to the availability of the least quantities of iodides necessary to synthesis hormones and to several other possible modifications such as a rise in the thyroxine-binding globulin and the thyroid stimulating effect of beta-hCG. An increase in size of the thyroid gland is very common. The interpretation of the parameters used to diagnose abnormalities of thyroid function can be carried out. Although the development of the fetal thyroid can take place independently of the maternal thyroid behaviour, an abnormal thyroid function in the mother can not occur without affecting the pregnancy. Grave's disease can cause either fetal or neonatal hyperthyroidism due to a transplacental transfer of thyroid stimulating immunoglobulins or hypothyroidism secondary to the use of too large doses of synthetic antithyroid products. Pregnancy itself favours hyperthyroidism. Maternal hypothyroidism which has not been treated is rarer because of a lack of fertility. It can cause repercussions on the fetus that have probably been over estimated. When pregnancy occurs in a hypothyroid woman who is being treated the dosages of drugs that she is being given should be increased by 20-30%. Providing a good knowledge of the thyroid parameters and keeping the patient preferably euthyroid in cases where thyroid dysfunction can occur, the pregnancy can continue normally whatever the state of the mother thyroid function was. The risks to the fetus are minimal. In women who are at risk it is very important to keep controlling the thyroid state after delivery when there is an immunological rebound which may lead to a relapse in Grave's disease and to post-partum thyroiditis. PMID:7693795

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

    PubMed

    Yorita Christensen, Krista L

    2013-11-01

    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. This study evaluates the association between biomarkers of metal exposure and thyroid hormones in the US population. Analyses included adults participating in the 2007-2008 National Health and Nutrition Examination Survey, with no history of thyroid disease or use of thyroid medications, and with data on metals in blood (lead, cadmium and mercury) and urine (lead, cadmium, mercury, barium, cobalt, cesium, molybdenum, antimony, thallium, tungsten and uranium), and thyroid hormones (TSH, free and total T3 and T4) in serum (N=1587). Multivariate linear regression was used to model the association between thyroid hormone levels, and metals in either urine (creatinine-adjusted) or blood. Metal concentrations were considered as both continuous and categorical variables. Models were adjusted for: age, sex, race, BMI, serum lipids, serum cotinine, pregnancy and menopausal status, and use of selected medications. Few participants (<5%) had free T3, free T4, or TSH levels outside the reference range. However, 9.2% (SE=1.2%) had low T3 and 9.4% (SE=1.1%) had low T4. Metals were detected in nearly all blood and urine samples, with the highest levels seen for urinary molybdenum (median 42.5μg/L). When including all blood metals, mercury was associated with decreases in T3 and T4, while cadmium was associated with decreased TSH. Urinary cadmium was associated with increases in both T3 and T4 (models including all metals measured in urine). Urinary thallium and barium were associated with decreased T4 (both) and T3 (barium). For TSH, cesium was associated with decreased, and tungsten with increased levels. Given the high prevalence of exposure to metals, associations of the size reported here could indicate an appreciable contribution of metals exposure to

  20. Mechanisms of Disruptive Action of Dichlorodiphenyltrichloroethane (DDT) on the Function of Thyroid Follicular Epitheliocytes.

    PubMed

    Yaglova, N V; Yaglov, V V

    2015-12-01

    The mechanism of disruptive action of dichlorodiphenyltrichloroethane (DDT) on the function of thyroid follicular epitheliocytes was examined in mature male Wistar rats administered with a daily dose of DDT (2 μg/kg) for 6 or 10 weeks. In 6 weeks, the serum level of Na(+)/I(-) symporter responsible for the transport of iodides into follicular thyrocytes decreased, while serum concentration of thyroperoxidase increased. In 10 weeks, both the number of follicles in the thyroid gland and serum level of Na(+)/I(-) symporter increased. In circulating blood, the concentrations of thyroglobulin as well as α and β receptors of the thyroid hormones did not change. DDT down-regulated the iodine-accumulated function of follicular thyrocytes by suppressing Na(+)/I(-) symporter synthesis. Recovery of Na(+)/I (-) symporter production resulted from up-regulation of the proliferative processes in thyroid gland. PMID:26621281

  1. Mechanisms of Disruptive Action of Dichlorodiphenyltrichloroethane (DDT) on the Function of Thyroid Follicular Epitheliocytes.

    PubMed

    Yaglova, N V; Yaglov, V V

    2015-12-01

    The mechanism of disruptive action of dichlorodiphenyltrichloroethane (DDT) on the function of thyroid follicular epitheliocytes was examined in mature male Wistar rats administered with a daily dose of DDT (2 μg/kg) for 6 or 10 weeks. In 6 weeks, the serum level of Na(+)/I(-) symporter responsible for the transport of iodides into follicular thyrocytes decreased, while serum concentration of thyroperoxidase increased. In 10 weeks, both the number of follicles in the thyroid gland and serum level of Na(+)/I(-) symporter increased. In circulating blood, the concentrations of thyroglobulin as well as α and β receptors of the thyroid hormones did not change. DDT down-regulated the iodine-accumulated function of follicular thyrocytes by suppressing Na(+)/I(-) symporter synthesis. Recovery of Na(+)/I (-) symporter production resulted from up-regulation of the proliferative processes in thyroid gland.

  2. Thyroid function, depressed mood, and cognitive performance in older individuals: the Maastricht Aging Study.

    PubMed

    van Boxtel, M P J; Menheere, P P C A; Bekers, O; Hogervorst, E; Jolles, J

    2004-08-01

    The hypothesis was tested that thyroid function, as indicated by serum thyroid-stimulating hormone (TSH) level, is associated with cognitive performance in a healthy aging population. In a random sample of 120 participants recruited from the Maastricht Aging Study (MAAS), aged between 49 and 71 years, we assessed TSH level, mood state (Symptom Check List, subscale depression), and three domains of cognitive function: verbal memory, general sensorimotor speed, and complex flexibility. After correction for age, sex, and educational level, a negative association between TSH and memory function was apparent: higher levels of TSH predicted lower levels of memory performance. Exclusion of individuals with TSH levels suspect for thyroid disorder (n=2) or who were on thyroid replacement (n=3) attenuated this association. Furthermore, additional control for mood status reduced the association below the significance level. No interaction between age and TSH on cognition was found, which indicated that the TSH-memory association was independent of age group level. We conclude that the association between TSH level and memory performance was small and dependent on mood status and the presence of (possible) thyroid disease in this relatively healthy population based sample. Prospective studies are needed to address the role of thyroid function in age-related cognitive decline.

  3. Thyroid hormone signaling in the Xenopus laevis embryo is functional and susceptible to endocrine disruption.

    PubMed

    Fini, J B; Le Mével, S; Palmier, K; Darras, V M; Punzon, I; Richardson, S J; Clerget-Froidevaux, M S; Demeneix, B A

    2012-10-01

    Thyroid hormone (TH) is essential for vertebrate brain development. Most research on TH and neuronal development focuses on late development, mainly the perinatal period in mammals. However, in human infants neuromotor development correlates best with maternal TH levels in the first trimester of pregnancy, suggesting that TH signaling could affect early brain development. Studying TH signaling in early embryogenesis in mammals is experimentally challenging. In contrast, free-living embryos, such as Xenopus laevis, permit physiological experimentation independent of maternal factors. We detailed key elements of TH signaling: ligands, receptors (TR), and deiodinases during early X. laevis development, before embryonic thyroid gland formation. Dynamic profiles for all components were found. Between developmental stages 37 and 41 (~48 h after hatching, coincident with a phase of continuing neurogenesis) significant increases in T(3) levels as well as in mRNA encoding deiodinases and TR occurred. Exposure of embryos at this developmental stage for 24 h to either a TH antagonist, NH-3, or to tetrabromobisphenol A, a flame retardant and known TH disruptor, differentially modulated the expression of a number of TH target genes implicated in neural stem cell function or neural differentiation. Moreover, 24-h exposure to either NH-3 or tetrabromobisphenol A diminished cell proliferation in the brain. Thus, these data show first, that TH signaling exerts regulatory roles in early X. laevis neurogenesis and second, that this period represents a potential window for endocrine disruption. PMID:22968643

  4. 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...

  5. [Effect of immunization on functional state of thyroid gland and thyroxine binding in rat organs].

    PubMed

    Serebrov, V Iu; Vasil'ev, N V; Udintsev, N A

    1982-02-01

    A number of modern research methods were used in experiments on 220 white rats to examine thyroid function at varying times after single immunization with typhoid vaccine. It was found that on the 1st and 2nd days of the observation period, only cAMP level of the thyroid parenchyma decreases. Three, four and seven days following immunization, thyroid function is drastically reduced, which manifests by a decrease in 131I uptake by the thyroid gland. Also decreased were the conversion ratio, the levels of thyroxine and triiodothyronine in blood serum and incorporation of labeled thyroxin by the heart, liver and spleen. During the productive phase of the immunogenesis (days 10, 15, 20 and 25), all the test indicators considerably increase. The phases of the reaction obtained seem likely to be a consequence of reciprocal relationship between the thyroid and sympathoadrenal systems (the inductive period), as well as by the feedback effect (the productive period of antibody formation). The reaction of thyroid function to immunization is regarded as a component of non-specific adaptation response of the body to an extreme irritant, that provides for metabolic reconstruction necessary for the synthesis of antibodies and formation of immune lymphocyte populations.

  6. Thyrotoxicosis caused by functioning metastatic thyroid carcinoma. A rare and elusive cause of hyperthyroidism with low radioactive iodine uptake

    SciTech Connect

    Ober, K.P.; Cowan, R.J.; Sevier, R.E.; Poole, G.J.

    1987-05-01

    A patient with progressively worsening thyrotoxicosis, refractory to medical therapy, is described. Repeated measurements of thyroidal RAI uptake over a 13 month period were low consistently and could not be explained by iodine ingestion, thyroiditis, or administration of exogenous thyroid hormone. An I-131 scan ultimately revealed striking activity at the base of the skull, reflecting ectopic excessive production of thyroid hormone by a solitary functioning metastatic thyroid carcinoma. The thyrotoxic state resolved after large doses of therapeutic I-131. Typical features of this rare cause of hyperthyroidism are discussed.

  7. Chronic thyroiditis (Hashimoto disease)

    MedlinePlus

    Laboratory tests to determine thyroid function include: Free T4 test Serum TSH T3 Thyroid autoantibodies Imaging studies and fine needle biopsy are generally not needed to diagnose Hashimoto thyroiditis. This disease may ...

  8. Variation in thyroid calibration efficiencies as a function of phantom design for I-125

    SciTech Connect

    Miltenberger, R.P.; Langille, E.; Sheetz, M.; Ricci, T.

    1987-01-01

    Four commercially available thyroid phantoms were evaluated to determine the effect that choice of phantom would have on the determination of I-125 activity in the thyroid. Efficiency calibration values for a 5.0-cm diameter 1-mm thick NaI (Tl) detector were determined as a function of distance from the phantom along the central axis and at angles up to 45 off axis using I-125 as the radionuclide of interest. Results indicate that substantial variations in the estimate of radioactivity in the thyroid will occur based on choice of calibration phantom. Using the Humanoid System, Inc. Realistic Phantom as the reference phantom, one could experience differences in estimated activity in the human thyroid that range from 0.86 to 2.94. 6 refs., 6 figs., 3 tabs.

  9. [Evaluation of thyroid diseases in nuclear medicine].

    PubMed

    Alimanović-Alagić, Rubina; Brković, Amera; Kucukalić-Selimović, Elma

    2008-01-01

    The thyroid is one of the larger endocrine glands in the body. The thyroid size is 15-20 gr. The gland produces hormones that regulate all metabolic processes in large number of tissues in the body, and produces hormones that affect the growth and rate of function of many other systems in the body. Studies of the endocrine system are among the original procedures in nuclear medicine. Thyroid scintigraphy and radio-tracer uptake studies remain an important part of the practice of nuclear medicine. Scintigraphy reveals functional and anatomic status of thyroid gland. A systematic and complete interpretation of the thyroid scintigrams requires assessments of thyroid size and configuration and identification and description of focal abnormalities, including hot and cold nodules and extrathyroidal activity in the neck or mediastinum. Early diagnosis and treatment of thyroid disease have made possible the reduction of morbidity and mortality associated with these disorders. PMID:19469277

  10. Thyroid Function in Small for Gestational Age Newborns: A Review

    PubMed Central

    Bagnoli, Franco; Laura, Farmeschi; Sara, Nappini; Salvatore, Grosso

    2013-01-01

    Several studies have shown that small for gestational age (SGA) babies have a different hormonal profile than those born with a birth weight appropriate for gestational age (AGA). Thyroid hormones play an important role in growth and neurocognitive development. Only few studies analyzed the concentrations of thyroid-stimulating hormone (TSH) and thyroxine (T4) during fetal and extrauterine life in SGA and AGA newborns, and the existing data on the possible alterations of these hormones in postnatal life are controversial. It remains to be established whether SGA newborns have different blood concentrations of thyroid hormones as compared with AGA infants and if so, whether these findings play a role in the development of obesity, short stature, hypertension, and diabetes - disorders, already known to be related with SGA birth. It has also not yet been established whether and when substitutive therapy with levothyroxine (LT4) should be initiated in preterm and full-term SGA newborns. Further trials are needed to determine the thyroid hormone profile in both preterm and full-term SGA newborns and also to evaluate the effectiveness and safety of LT4 treatment in these infants. Conflict of interest:None declared. PMID:23149390

  11. Thyroid function in small for gestational age newborns: a review.

    PubMed

    Franco, Bagnoli; Laura, Farmeschi; Sara, Nappini; Salvatore, Grosso

    2013-01-01

    Several studies have shown that small for gestational age (SGA) babies have a different hormonal profile than those born with a birth weight appropriate for gestational age (AGA). Thyroid hormones play an important role in growth and neurocognitive development. Only few studies analyzed the concentrations of thyroid-stimulating hormone (TSH) and thyroxine (T4) during fetal and extrauterine life in SGA and AGA newborns, and the existing data on the possible alterations of these hormones in postnatal life are controversial. It remains to be established whether SGA newborns have different blood concentrations of thyroid hormones as compared with AGA infants and if so, whether these findings play a role in the development of obesity, short stature, hypertension, and diabetes--disorders, already known to be related with SGA birth. It has also not yet been established whether and when substitutive therapy with levothyroxine (LT4) should be initiated in preterm and full-term SGA newborns. Further trials are needed to determine the thyroid hormone profile in both preterm and full-term SGA newborns and also to evaluate the effectiveness and safety of LT4 treatment in these infants.

  12. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine.

    PubMed

    Leach, Prescott T; Gould, Thomas J

    2015-10-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to the addictive liability of nicotine. Nicotine modulates aspects of the endocrine system, including the thyroid, which is critical for normal cognitive functioning. It is possible that nicotine's effects on thyroid function may alter learning and memory, and this may underlie some of its addictive potential. Here, we review the literature on thyroid function and cognition, with a focus on how nicotine alters thyroid hormone signaling and the potential impact on cognition. Changes in cognition are a major symptom of nicotine addiction. Current anti-smoking therapies have modest success at best. If some of the cognitive effects of nicotine are mediated through the thyroid hormone system, then thyroid hormone agonists may be novel treatments for smoking cessation therapies. The content of this review is important because it clarifies the relationship between smoking and thyroid function, which has been ill-defined in the past. This review is timely because the reduction in smoking rates we have seen in recent decades, due to public awareness campaigns and public smoking bans, has leveled off in recent years. Therefore, novel treatment approaches are needed to help reduce smoking rates further. PMID:26344666

  13. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine.

    PubMed

    Leach, Prescott T; Gould, Thomas J

    2015-10-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to the addictive liability of nicotine. Nicotine modulates aspects of the endocrine system, including the thyroid, which is critical for normal cognitive functioning. It is possible that nicotine's effects on thyroid function may alter learning and memory, and this may underlie some of its addictive potential. Here, we review the literature on thyroid function and cognition, with a focus on how nicotine alters thyroid hormone signaling and the potential impact on cognition. Changes in cognition are a major symptom of nicotine addiction. Current anti-smoking therapies have modest success at best. If some of the cognitive effects of nicotine are mediated through the thyroid hormone system, then thyroid hormone agonists may be novel treatments for smoking cessation therapies. The content of this review is important because it clarifies the relationship between smoking and thyroid function, which has been ill-defined in the past. This review is timely because the reduction in smoking rates we have seen in recent decades, due to public awareness campaigns and public smoking bans, has leveled off in recent years. Therefore, novel treatment approaches are needed to help reduce smoking rates further.

  14. Thyroid hormone signaling: Contribution to neural function, cognition, and relationship to nicotine

    PubMed Central

    Leach, Prescott T.; Gould, Thomas J.

    2015-01-01

    Cigarette smoking is common despite its adverse effects on health, such as cardiovascular disease and stroke. Understanding the mechanisms that contribute to the addictive properties of nicotine makes it possible to target them to prevent the initiation of smoking behavior and/or increase the chance of successful quit attempts. While highly addictive, nicotine is not generally considered to be as reinforcing as other drugs of abuse. There are likely other mechanisms at work that contribute to the addictive liability of nicotine. Nicotine modulates aspects of the endocrine system, including the thyroid, which is critical for normal cognitive functioning. It is possible that nicotine’s effects on thyroid function may alter learning and memory, and this may underlie some of its addictive potential. Here, we review the literature on thyroid function and cognition, with a focus on how nicotine alters thyroid hormone signaling and the potential impact on cognition. Changes in cognition are a major symptom of nicotine addiction. Current anti-smoking therapies have modest success at best. If some of the cognitive effects of nicotine are mediated through the thyroid hormone system, then thyroid hormone agonists may be novel treatments for smoking cessation therapies. The content of this review is important because it clarifies the relationship between smoking and thyroid function, which has been ill-defined in the past. This review is timely because the reduction in smoking rates we have seen in recent decades, due to public awareness campaigns and public smoking bans, has leveled off in recent years. Therefore, novel treatment approaches are needed to help reduce smoking rates further. PMID:26344666

  15. 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

  16. Comparison of methods for assessing thyroid function in nonthyroidal illness

    SciTech Connect

    Melmed, S.; Geola, F.L.; Reed, A.W.; Pekary, A.E.; Park, J.; Hershman, J.M.

    1982-02-01

    Various tests of thyroid function were studied in sick patients with nonthyroidal illness (NTI) in order to determine the utility of each test for differentiating these patients from a group with hypothyroidism. We evaluated each test in 22 healthy volunteers who served as controls, 20 patients with hypothyroidism, 14 patients admitted to medical intensive care unit whose serum T/sub 4/ was less than 5 ..mu..g/dl, 13 patients with chronic liver disease, 32 patients on chronic hemodialysis for renal failure, 13 ambulatory oncology patients receiving chemotherapy 16 pregnant women, 7 women on estrogens, and 20 hyperthyroid patients. On all samples, we measured serum T/sub 4/, the free T/sub 4/ index by several methods, free T/sub 4/ by equilibrium dialysis, free T/sub 4/ calculated from thyronine-binding globulin (TBG) RIA, free T/sub 4/ by three commercial kits (Gammacoat, Immophase, and Liquisol), T/sub 3/, rT/sub 3/, and TSH (by 3 different RIA). Although all of the methods used for measuring free T/sub 4/ (including free T/sub 4/ index, free T/sub 4/ by dialysis, free T/sub 4/ assessed by TBG, and free T/sub 4/ assessed by the 3 commercial kits) were excellent for the diagnosis of hypothyroidism, hyperthyroidism, and euthyroidism in the presence of high TBG, none of these methods showed that free T/sub 4/ was consistently normal in patients with NTI; with each method, a number of NTI patients had subnormal values. In the NTI groups, free T/sub 4/ measured by dialysis and the free T/sub 4/ index generally correlated significantly with the commercial free T/sub 4/ methods. Serum rT/sub 3/ was elevated or normal in NTI patients and low in hypothyroid subjects. Serum TSH provided the most reliable differentiation between patients with primary hypothyroidism and those with NTI and low serum T/sub 4/ levels.

  17. Zebrafish eleutheroembryos as an alternative system for screening chemicals disrupting the mammalian thyroid gland morphogenesis and function.

    PubMed

    Raldúa, Demetrio; Thienpont, Benedicte; Babin, Patrick J

    2012-04-01

    The importance and irreversibility of the effects of thyroid hormone deficiency on human brain development highlight the importance of identifying environmental agents that interfere with thyroid gland morphogenesis and function. Zebrafish eleutheroembryos are currently used by many pharmaceutical companies in drug discovery as a vertebrate model, not subjected to regulations for animal experiments, that provides an intermediate step between in vitro and rodent assay. The mechanisms of zebrafish thyroid development are generally comparable to those in humans, and moreover, molecular and functional studies of zebrafish thyroid follicles have demonstrated a high degree of conservation with upper vertebrates, opening up the possibility of designing alternative methods for screening individual chemicals and mixtures that impairing thyroid gland morphogenesis and/or function. Analysis of the intrafollicular thyroxine-content of zebrafish larvae exposed to potential disruptors has proved to be a reliable, physiologically relevant endpoint to estimate effects of chemicals on the mammalian thyroid gland. PMID:21978863

  18. Testicular function in patients with differentiated thyroid carcinoma treated with radioiodine

    SciTech Connect

    Pacini, F.; Gasperi, M.; Fugazzola, L.

    1994-09-01

    The aim of the present study was to assess whether {sup 131}I therapy for differentiated thyroid carcinoma (DTC) can affect endocrine testicular function. Serum follicle-stimulating hormone (FSH) and testosterone (T) concentrations were measured in 103 patients periodically submitted for radioiodine therapy for residual or metastatic disease. Mean follow-up was 93.7{+-}54 mo (range 10-243 mo). Mean FSH values in {sup 131}I-treated patients tested after their last treatment were 15.3{+-}9.9 mU/ml, significantly higher than those of 19 untreated patients (6.5{+-}3.1 mU/ml). Considering the mean +3 s.d. FSH of untreated subjects as the upper limit of normal range, 36.8% of the patients had an abnormal increase in serum FSH. Longitudinal analysis performed in 21 patients showed that the behavior of FSH in response to {sup 131}I therapy was not universal. Six patients had no change or a slight increase in serum FSH after {sup 131}I administration; eleven patients had a transient increase above normal values 6-12 mo after {sup 131}I treatment, with return to normal levels in subsequent months. The administration of a second dose was followed by a similar increase in FSH levels. Finally, four patients, followed for a long period of time and treated with several {sup 131}I doses, showed a progressive increase in serum FSH, which eventually became permanent. Semen analysis, performed in a small subgroup of patients, showed a consistent reduction in the number of normokinetic sperm. No change was found in serum T levels between treated and untreated patients. The results indicate that {sup 131}I therapy for thyroid carcinoma is associated with transient impairment of testicular germinal cell function. The damage may become permanent for high-radiation activities delivered year after year and might pose a significant risk of infertility. 14 refs., 8 figs., 1 tab.

  19. Indices of Central and Peripheral Obesity; Anthropometric Measurements and Laboratory Parameters of Metabolic Syndrome and Thyroid Function

    PubMed Central

    Aras, Şükrü; Üstünsoy, Seyfettin; Armutçu, Ferah

    2015-01-01

    Background: Metabolic syndrome (MetS) and obesity are serious health problems in the World, including Turkey. Contemporary studies have suggested a meaningful association between insulin resistance (IR), MetS parameters, and thyroid function tests. Aims: We aimed to elucidate the impact of fat distribution on the anthropometric and laboratory parameters, especially indices of MetS, IR and thyroid function, in obese women. Study Design: Cross-sectional study. Methods: Anthropometric measurements of all participants and biochemical tests in their serum samples were performed. Results: Weight, waist circumference (WC), body mass index (BMI), and other parameters of fat distribution were significantly increased in all obese compared to control subjects; but there was no significant difference between central and peripheral obese groups. The central obese group had significantly higher insulin levels, components of MetS, the ratio free triiodothyronine (fT3) to free thyroxin fT4, and fT4 than those of peripheral obese and control groups. Conclusion: Elevated triglyceride, glucose and insulin levels may be associated with increased IR, which in turn is related to MetS. Body fat composition may affect thyroid tests in the obese; the changes in fT3/fT4 could be the consequence of fat distribution. PMID:26740903

  20. Evaluation of thyroid function in children with undiagnosed short stature in north India.

    PubMed

    Virmani, A; Menon, P S; Karmarkar, M G; Kochupillai, N; Seth, V; Ghai, O P; Gopinath, P G

    1987-09-01

    Fifty-five children with short stature were investigated for the aetiology of short stature with special reference to hypothyroidism. Clinical and laboratory parameters including anthropometry were determined to exclude any chronic systemic disorders. Thyroid function tests such as thyroxine (T4) and thyroid stimulating hormone (TSH) estimation by radioimmunoassay, radioactive iodine uptake and thyroid scan, using 131I and perchlorate discharge test, were performed. In addition, growth hormone was estimated under basal conditions and after insulin-induced hypoglycaemia. Thirty-five were boys and 20 were girls. The age at presentation in the boys was 3-12 years whereas in the girls it was 8-13 years. Forty-three of the 55 children had delayed bone age. Abnormal thyroid function was present in 25 children (45.45%). Of these, 11 (20%) had primary hypothyroidism with low or normal uptake, whereas 14 (25.45%) had glands with high uptake of 131I and elevated TSH. Three children with primary hypothyroidism had reduced growth hormone reserve. On follow-up with thyroxine, there was an increase in growth velocity in all. This study indicates that thyroid function tests should be performed routinely in children with undiagnosed short stature.

  1. Neurologic development of the newborn and young child in relation to maternal thyroid function.

    PubMed

    Smit, B J; Kok, J H; Vulsma, T; Briët, J M; Boer, K; Wiersinga, W M

    2000-03-01

    A prospective observational study was performed in pregnant women with known thyroid disease. We studied the effect of maternal thyroid function in the first half of pregnancy on the neurologic development of the infant in the first 2 y of life. Clinical and thyroid function data were collected from 20 pregnant women with known thyroid disease and their newborn children. Infants were divided into three groups according to their maternal thyroid function within the first half of pregnancy: Group A (n = 7): maternal subclinical hypothyroidism, Group B (n = 6): maternal euthyroidism, and Group C (n = 7): maternal hyperthyroidism or subclinical hyperthyroidism. Neurophysiologic, i.e. motor nerve conduction velocity and somatosensory evoked potentials and neurologic and developmental (Bayley scales) assessments were done. One infant, born to a mother with Graves' disease, developed transient hyperthyroidism. At the age of 6 and 12 mo, the mean mental developmental index (MDI) score was 16 points lower for infants in Group A than for those in Group B (p = 0.03 and 0.02, respectively). At the age of 24 mo, the mean MDI score was 6 points lower, which was not statistically significant. Neurophysiologic and neurologic assessments and the mean Psychomotor Developmental scores did not differ among the three groups. In conclusion, maternal subclinical hypothyroidism in the first half of pregnancy was associated with a lower mean MDI score in their infants during the first year of life.

  2. Thyroid hormone status affects expression of daily torpor and gene transcription in Djungarian hamsters (Phodopus sungorus).

    PubMed

    Bank, Jonathan H H; Kemmling, Julia; Rijntjes, Eddy; Wirth, Eva K; Herwig, Annika

    2015-09-01

    Thyroid hormones (TH) play a key role in regulation of seasonal as well as acute changes in metabolism. Djungarian hamsters (Phodopus sungorus) adapt to winter by multiple changes in behaviour and physiology including spontaneous daily torpor, a state of hypometabolism and hypothermia. We investigated effects of systemic TH administration and ablation on the torpor behaviour in Djungarian hamsters adapted to short photoperiod. Hyperthyroidism was induced by giving T4 or T3 and hypothyroidism by giving methimazole (MMI) and sodium perchlorate via drinking water. T3 treatment increased water, food intake and body mass, whereas MMI had the opposite effect. Continuous recording of body temperature revealed that low T3 serum concentrations increased torpor incidence, lowered Tb and duration, whereas high T3 serum concentrations inhibited torpor expression. Gene expression of deiodinases (dio) and uncoupling proteins (ucp) were analysed by qPCR in hypothalamus, brown adipose tissue (BAT) and skeletal muscle. Expression of dio2, the enzyme generating T3 by deiodination of T4, and ucps, involved in thermoregulation, indicated a tissue specific response to treatment. Torpor per se decreased dio2 expression irrespective of treatment or tissue, suggesting low intracellular T3 concentrations during torpor. Down regulation of ucp1 and ucp3 during torpor might be a factor for the inhibition of BAT thermogenesis. Hypothalamic gene expression of neuropeptide Y, propopiomelanocortin and somatostatin, involved in feeding behaviour and energy balance, were not affected by treatment. Taken together our data indicate a strong effect of thyroid hormones on torpor, suggesting that lowered intracellular T3 concentrations in peripheral tissues promote torpor.

  3. Thyroid hormone, brain development, and the environment.

    PubMed Central

    Zoeller, Thomas R; Dowling, Amy L S; Herzig, Carolyn T A; Iannacone, Eric A; Gauger, Kelly J; Bansal, Ruby

    2002-01-01

    Thyroid hormone is essential for normal brain development. Therefore, it is a genuine concern that thyroid function can be altered by a very large number of chemicals routinely found in the environment and in samples of human and wildlife tissues. These chemicals range from natural to manufactured compounds. They can produce thyroid dysfunction when they are absent from the diet, as in the case of iodine, or when they are present in the diet, as in the case of thionamides. Recent clinical evidence strongly suggests that brain development is much more sensitive to thyroid hormone excess or deficit than previously believed. In addition, recent experimental research provides new insight into the developmental processes affected by thyroid hormone. Based on the authors' research focusing on the ability of polychlorinated biphenyls to alter the expression of thyroid hormone-responsive genes in the developing brain, this review provides background information supporting a new way of approaching risk analysis of thyroid disruptors. PMID:12060829

  4. Recessive resistance to thyroid hormone in mice lacking thyroid hormone receptor beta: evidence for tissue-specific modulation of receptor function.

    PubMed Central

    Forrest, D; Hanebuth, E; Smeyne, R J; Everds, N; Stewart, C L; Wehner, J M; Curran, T

    1996-01-01

    The diverse functions of thyroid hormone (T3) are presumed to be mediated by two genes encoding the related receptors, TRalpha and TRbeta. However, the in vivo functions of TRalpha and TRbeta are undefined. Here, we report that targeted inactivation of the mouse TRbeta gene results in goitre and elevated levels of thyroid hormone. Also, thyroid-stimulating hormone (TSH), which is released by pituitary thyrotropes and which is normally suppressed by increased levels of thyroid hormone, was present at elevated levels in homozygous mutant (Thrb-/-) mice. These findings suggest a unique role for TRbeta that cannot be substituted by TRalpha in the T3-dependent feedback regulation of TSH transcription. Thrb-/- mice provide a recessive model for the human syndrome of resistance to thyroid hormone (RTH) that exhibits a similar endocrine disorder but which is typically caused by dominant TRbeta mutants that are transcriptional inhibitors. It is unknown whether TRalpha, TRbeta or other receptors are targets for inhibition in dominant RTH; however, the analysis of Thrb-/- mice suggests that antagonism of TRbeta-mediated pathways underlies the disorder of the pituitary-thyroid axis. Interestingly, in the brain, the absence of TRbeta may not mimic the defects often associated with dominant RTH, since no overt behavioural or neuroanatomical abnormalities were detected in Thrb-/- mice. These data define in vivo functions for TRbeta and indicate that specificity in T3 signalling is conferred by distinct receptor genes. Images PMID:8670802

  5. [The impact of thyroid function in women of reproductive age: infertility, pregnancy and the postpartum period].

    PubMed

    Speer, Gábor

    2013-12-22

    This article reviews the management and diagnosis of thyroid dysfunction during pregnancy and postpartum, which was published by any of the endocrine societies in 2012. The author presents human data based on these clinical practice guidelines, however, there are also many unresolved questions. Especially, there are inconsistencies about screening using plasma TSH measurement. In pregnancy the main causes of hyperthyroidism are Graves's disease and gestational transient thyrotoxicosis. Generally, gestational transient thyrotoxicosis does not require medication, whereas Graves's disease needs antithyroid drug therapy. Postpartum thyroiditis occurs more frequently in antithyroid peroxidase-positive women, who should be screened using serum thyrotropin measurements at 6 to 12 gestation weeks and at 3 and 6 months postpartum. Because overt maternal hypothyroidism, due to autoimmune pathophysioloical mechanisms, negatively affects the fetus, timely recognition and treatment are important. The subclinical form of maternal hypothyroidism should also be treated. A link between thyroid dysfunction and infertility has been warranted. PMID:24334133

  6. Effects of plasticizers and their mixtures on estrogen receptor and thyroid hormone functions.

    PubMed

    Ghisari, Mandana; Bonefeld-Jorgensen, Eva Cecilie

    2009-08-25

    Plasticizers are additives used to increase the flexibility or plasticity of the material to which they are added, normally rigid plastic and as additives in paint and adhesives. They are suspected to interfere with the endocrine system, including the estrogen and the thyroid hormone (TH) systems. We investigated in vitro the thyroid hormone-like and estrogenic activities of a range of widely used plasticizers and phenols including benzyl butyl phthalate (BBP), dibutyl phthalate (DBP), dioctyl phthalate (DOP), diisodecyl phthalate (DIDP), diisononyl phthalate (DINP), di(2-ethylhexyl) phthalate (DEHP), bis(2-ethylhexyl) adipate (DEHA), 4-tert-octylphenol (tOP), 4-chloro-3-methylphenol (CMP), 2,4-dichlorophenol (2,4-DCP), 2-phenylphenol (2-PP) and resorcinol. The TH disrupting potential was determined by the effect on the TH-dependent rat pituitary GH3 cell proliferation (T-screen). The estrogenic activities of the compounds were assessed in MVLN cells, stably transfected with an estrogen receptor (ER) luciferase reporter vector. Furthermore, the combined effect of a multi-components mixture of six plasticizers was evaluated for its estrogenic and TH-like activities. All the tested compounds, but 2-PP, significantly affected the GH3 cell proliferation. tOP, BBP and DBP activated ER transactivity, whereas DEHP antagonized the 17beta-estradiol induced ER function. The mixture significantly induced ER transactivity in an additive manner, whereas in the T-screen, the observed mixture effect was lower than predicted, suggesting a potential antagonizing effect of the mixture. In conclusion, the tested plasticizers and phenols elicited endocrine-disrupting potential that can be mediated via interference with the estrogen and TH systems. Moreover, the observed mixture effect stresses the importance of considering the combined effect of the compounds for risk assessment of human health. PMID:19463926

  7. Human Exposures to Bisphenol A, Bisphenol F and Chlorinated Bisphenol A Derivatives and Thyroid Function

    PubMed Central

    Andrianou, Xanthi D.; Gängler, Stephanie; Piciu, Andra; Charisiadis, Pantelis; Zira, Christina; Aristidou, Kyriacos; Piciu, Doina; Hauser, Russ; Makris, Konstantinos C.

    2016-01-01

    Although the increasing prevalence of thyroid nodular disease (TND) has been partially attributed to the more frequent usage of improved diagnostics, environmental factors, such as exposures to thyroid-disrupting chemicals may contribute to TND and altered thyroid function. We investigated the association between exposures to bisphenol A (BPA), its chlorinated derivatives (ClxBPA), and bisphenol F (BPF) with TND and thyroid measures in adult women. A case-control study in Cyprus and Romania (n = 212) was conducted, where cases were those with thyroid nodules (diameter >3mm), and controls without nodules. Serum TSH and free thyroxine and urinary levels of BPA, BPF and ClxBPA were measured using immunoassays and tandem mass spectrometry, respectively. The association between exposures to BPA compounds and TND, adjusting for age, BMI, thyroid hormones and urinary iodine was assessed using logistic regression. Linear regression was used to explore associations between urinary BPA, BPF and ClxBPA and serum thyroid hormones. With the exception of a chlorinated BPA compound (30%), the rest of bisphenols were quantified in 100% of urine samples. A positive and significant (p<0.05) association was observed between urinary BPA and serum TSH that remained after adjusting for urinary creatinine, age, BMI, study site and disease status; there was no significant association between BPF or ClxBPA with TSH. None of the BPA compounds were associated with higher odds of TND. Our study found associations of urinary BPA with TSH but not with BPF or ClxBPA. A larger study would be justified. PMID:27783680

  8. Thyroid function in healthy normal, low birthweight and preterm infants.

    PubMed

    Bongers-Schokking, J J; Schopman, W

    1984-12-01

    To delineate more precisely the role of gestational age, weight at birth and thyroid status at birth on the postnatal changes in thyroid hormone levels, serum T4, T3, TSH and in some cases FT3I were measured at birth and at 3-4 h, 24-30 h, 6-9 days and 13-20 days. Subjects studied were healthy appropriate-for-date (AFD) and small-for-date (SFD) term neonates and healthy AFD and SFD preterm children. At birth T4 and T3 are related to both gestational age and weight with T4 and T3 showing lower values in preterm and SFD term neonates than in AFD term children. After birth T4 and T3 concentrations show a better correlation with gestational age than with weight at birth. For TSH no correlation was found at birth, a positive correlation at 24-30 h, no correlation at 6-9 days and a negative correlation at 13-20 days both with gestational age and weight at birth. In term and close-to-term infants (36 weeks) individual T4 levels at 6-7 days show a close relationship with those at birth; in the younger children (34 and 35 weeks) lower T4 values are found, despite equal cord blood values. The individual cord blood FT3I/TSH values correlate well with those at 6-7 days of age. It is concluded that after birth all children have changing T4 and T3 values, but the pattern and level are influenced by the maturity of the child and its thyroid status at birth measured by T4 and by the FT3I/TSH ratio.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:6335089

  9. 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

  10. Preservation of renal function by thyroid hormone replacement in elderly persons with subclinical hypothyroidism

    PubMed Central

    Guo, Hong; Liu, Dongmei; Zhao, Zhen

    2016-01-01

    Introduction The treatment of subclinical hypothyroidism in elderly persons is controversial. Previous studies have shown that there are interactions between kidney and thyroid function, but data regarding interventions that target thyroid function in elderly patients are scarce. We aimed to investigate the impact of thyroid hormone therapy on the estimated glomerular filtration rate (eGFR) in elderly patients. Material and methods Ninety elderly patients aged ≥ 65 years with subclinical hypothyroidism were followed for 36 months in our case-control study. The changes in the eGFR in patients with and without thyroid hormone replacement therapy were compared. The adverse effects during the treatment period were noted. Results The eGFR of both groups was similar at the beginning of the study (43.4 ±6.1 vs. 42.8 ±5.9 ml/min/1.73 m2; p = 0.62). With the decline in thyroid stimulating hormone levels after treatment, the eGFR of the treatment group significantly improved compared with the control group (45.8 ±4.8 vs. 35.8 ±5.3 ml/min/1.73 m2; p < 0.001); the eGFR increased rapidly over the first 6 months and then plateaued. No patients withdrew from the study, but the therapeutic dose was decreased in two patients due to angina pectoris. Conclusions Thyroid hormone therapy preserved renal function in elderly patients. Appropriate individual treatment should be considered in elderly patients with subclinical hypothyroidism. PMID:27478458

  11. Placebo Sleep Affects Cognitive Functioning

    ERIC Educational Resources Information Center

    Draganich, Christina; Erdal, Kristi

    2014-01-01

    The placebo effect is any outcome that is not attributed to a specific treatment but rather to an individual's mindset (Benson & Friedman, 1996). This phenomenon can extend beyond its typical use in pharmaceutical drugs to involve aspects of everyday life, such as the effect of sleep on cognitive functioning. In 2 studies examining whether…

  12. Alterations in thyroid function among the different polycystic ovary syndrome phenotypes.

    PubMed

    Morgante, Giuseppe; Musacchio, Maria Concetta; Orvieto, Raoul; Massaro, Maria Giulia; De Leo, Vincenzo

    2013-11-01

    The study evaluates the prevalence of subclinical thyroid dysfunction in infertile PCOS patients, according to the different PCOS phenotypes and to examine whether insulin sensitizers in insulin resistant (IR) PCOS patients may improve thyroid function. The study population consisted of all PCOS patients, attending the infertility and IVF unit of Department of Pediatrics, Obstetrics and Reproductive Medicine of University of Siena, Italy, and compared them to regularly cycling, healthy, infertile controls. Upon admission, blood was drawn from all patients during the early follicular phase, for complete hormonal and metabolic profiles. In IR-PCOS patients treated with insulin sensitizers, blood was drawn again after 6 months. PCOS patients had a significantly higher prevalence of subclinical thyroid dysfunction compared to infertile controls. While no significant association was detected between TSH value and the presence of hyperandrogenism, overweight and obese PCOS patients, as well as IR PCOS patients showed significantly higher prevalence of subclinical thyroid dysfunction. Moreover, among IR PCOS patients, 6 months treatment with insulin sensitizers significantly reduces TSH levels. Infertile PCOS patients have a high prevalence of subclinical thyroid dysfunction, which may be successfully treated in IR PCOS patients by insulin sensitizers.

  13. Analysis of the functional state of T3 nuclear receptors expressed in thyroid cells.

    PubMed

    Selmi-Ruby, S; Rousset, B

    1996-05-17

    T3 nuclear receptors (TR) are present in thyroid cells. We have analyzed the ability of thyroid TR to function as transcriptional regulators. Studies were performed on pig thyrocytes in primary culture. Messenger RNA corresponding to TR alpha 1, alpha 2 and beta were detected in pig thyrocytes by RT-PCR and Northern blot; the alpha 2 mRNA was more abundant than the alpha 1 mRNA. Thyrocytes were transiently transfected with different plasmids containing the CAT (chloramphenicol acetyl transferase) gene placed under the control of different promoters (delta MTV, TK or delta SV40) and bearing a thyroid hormone response element, TREp or TRE DR + 4. It was found that TSH induced a concentration-dependent increase of the transfection efficiency, an effect reproduced by (Bu)2cAMP and Forskolin. Cells transfected with either delta MTV-, TK- or delta SV40-TREp-CAT expressed similar basal CAT activities. Addition of T3 produced a 3-fold increase of CAT activity expressed from each of these vectors. In contrast, CAT activity expressed from a vector containing the TRE DR + 4 was decreased by about 50% by T3. Thus, TREp and TRE DR + 4 gave distinct responses. These data demonstrate that TR physiologically expressed in thyroid cells can act as transcriptional regulators in a T3-dependent manner. This finding directly substantiates the concept of autocrine regulatory actions of thyroid hormones. PMID:8793858

  14. Culture of hormone-dependent functional epithelial cells from rat thyroids.

    PubMed Central

    Ambesi-Impiombato, F S; Parks, L A; Coon, H G

    1980-01-01

    Primary cultures of rat thyroid cells were made in medium supplemented with 0.1--0.5% calf serum and containing six hormones or growth factors: insulin, thyrotropin, transferrin, hydrocortisone, somatostatin, and glycyl-L-histidyl-L-lysine acetate. The FRTL strain was purified by successive colonial isolations and was found to maintain highly differentiated features (secretion into the culture medium of physiological amounts of thyroglobulin and concentration of iodide by 100-fold). The FRTL strain has been observed for more than 3 years in continuous culture. It has maintained the same biochemical and morphological characteristics that typified the primary cultures of thyroid follicular cells immediately after their enzymatic release from the rat thyroid. Thyroid epithelial cells that were grown under more conventional cell culture conditions failed to retain these specialized characteristics. We show that maintenance in vitro of these specialized functions of rat thyroid follicular cells is dependent on low serum concentrations and supplementation with hormones in the primary cultures. Our observations indicate that this culture strategem may be aplicable to the general problem of maintenance of differentiated characteristics in cultures of other epithelial cells. Images PMID:6106191

  15. Effect of lead nitrate on thyroid function on the Indian palm squirrel, Funambulus pennanti (Wroughton)

    SciTech Connect

    Shrivastava, V.K.; Katti, S.R.; Sathyanesan, A.G.

    1987-06-01

    Some of the known toxic effects of lead in mammals including man are, impaired heme synthesis, anemia, nepatopathy, nephropathy, behavioral disorders and neuropathy. However, very little is known about the effect of lead on endocrine physiology. Some data are available on lead induced impairment of thyroid function in occupationally exposed men and experimental rats. As lead nitrate is largely consumed through water and food, in this study the wild rodents Funambulus pennanti were administered lead through their drinking water and their thyroid structure, radioiodine 131-I percentage uptake and protein bound iodine (PBI) level were assessed.

  16. Thyroid gland development and defects.

    PubMed

    Kratzsch, Juergen; Pulzer, Ferdinand

    2008-02-01

    During the functional ontogenesis of the thyroid gland an increasing number of transcription factors play fundamental roles in thyroid-cell differentiation, maintenance of the differentiated state, and thyroid-cell proliferation. The early growth and development of the fetal thyroid appears to be generally independent of thyroid-stimulating hormone (TSH). TSH and thyroxine (T4) levels increase from the 12th week of gestation until delivery, whereas triiodothyronine (T3) levels remain relatively low. At birth, a cold-stimulated short-lived TSH surge is observed, followed by a TSH decrease until day 3 or 4 of life by T4 feedback inhibition. Disorders of thyroid gland development and/or function are relatively common, affecting approximately one newborn infant in 2000-4000. The most prevalent disease, congenital hypothyroidism, is frequently caused by genetic defects of transcription factors involved in the development of the thyroid or pituitary gland. A major cause of congenital hyperthyroidism is the transplacental passage of stimulating thyrotropin antibodies from the mother to the fetus. Hypothyroxinaemia or hypotriiodthyroninaemia is frequently observed in preterm infants with or without severe non-thyroidal illness. Whereas congenital hypo- and hyperthyroidism may be treated successfully with T4 or thyrostatic drugs, there is still insufficient evidence on whether the use of T4 for treatment of the latter condition results in changes in neonatal morbidity or reductions in neurodevelopmental impairment.

  17. THE EFFECTS OF ATRAZINE METABOLITES ON PUBERTY AND THYROID FUNCTION IN THE MALE WISTAR RAT

    EPA Science Inventory

    The Effects of Atrazine Metabolites on Puberty and Thyroid Function in the Male Wistar Rat. Stoker, T.E1., Guidici, D.L.2, Laws, S.C.2 and Cooper, R.L.2 Gamete and Early Embryo Biology Branch and 2 Endocrinology Branch, Reproductive Toxicology Division, National Health and Envir...

  18. 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...

  19. Postnatal overnutrition programs the thyroid hormone metabolism and function in adulthood.

    PubMed

    Lisboa, Patricia C; Conceição, Ellen P S; de Oliveira, Elaine; Moura, Egberto G

    2015-09-01

    Early overnutrition (EO) during lactation leads to obesity, leptin resistance and lower thyroid hormone (TH) levels during adulthood. To better understand the biological significance of this thyroid hypofunction, we studied the long-term effects of postnatal EO on both the function of hypothalamic-pituitary-thyroid (HPT) axis and the metabolism and action of TH. To induce EO, the litter size was reduced to three pups per litter (small litter (SL) group) on the third day of lactation. In the controls (normal litter group), litter size was adjusted to 10 pups per litter. Rats were killed at PN180. TRH content and in vitro TSH were evaluated. Iodothyronine deiodinase (D1 and D2) activities were measured in different tissues. Mitochondrial α-glycerol-3-phosphate dehydrogenase (mGPD), uncoupling protein 1 (UCP1) and TH receptor (TRβ1) were evaluated to assess TH action. The SL group presented lower TRH, intra-pituitary and released TSH levels, despite unchanged plasma TSH. They presented lower D1 activity in thyroid, muscle and white adipose tissue (WAT) and higher D2 activity in the hypothalamus, pituitary, brown adipose tissue (BAT) and WAT, which confirmed the hypothyroidism. UCP1 in BAT and TRβ1 in WAT were decreased, which can contribute to a lower catabolic status. Despite the lower TH, the D2 activity in the thyroid, heart and testes was unchanged. Hepatic D1, mGPD and TRβ1 were also unchanged in SL rats, suggesting that the TH conversion and action were preserved in the liver, even with lower TH. Thus, this model indicates that postnatal EO changes thyroid function in adult life in a tissue-specific way, which can help in the understanding of obesogenesis. PMID:26203167

  20. Maternal Urinary Bisphenol A during Pregnancy and Maternal and Neonatal Thyroid Function in the CHAMACOS Study

    PubMed Central

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

    2012-01-01

    Background: 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. Objective: Our goal was to evaluate whether exposure to BPA during pregnancy is related to thyroid hormone levels in pregnant women and neonates. Methods: 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. Results: 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. Conclusion: 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. PMID:23052180

  1. [Thyroid dysfunction in pregnancy].

    PubMed

    Führer, D; Mann, K; Feldkamp, J; Krude, H; Spitzweg, C; Kratzsch, J; Schott, M

    2014-10-01

    Thyroid dysfunction may impair fertility, course of pregnancy and fetal development. Physiological alterations of thyroid function parameters, that occur during pregnancy need to be distinguished from pathophysiological states of hypo- and hyperthyroidism. We performed a literature search (PubMed 1990-2013) and review relevant publications as well as consensus and practice guidelines of international thyroid/endocrine societies. Interpretation of thyroid function values in pregnancy must be based on trimester-specific TSH and T4 ranges. Alterations in thyroid function are present in up to 15% of pregnancies (0.4% overt hypothyroidism, 0.1-0.4% hyperthyroidism) and may lead to preventable complications in the pregnant woman and the fetus. Hypothyroidism is associated with an increased risk for abortion, premature delivery and stillbirth, besides impairment of neurocognitive development. The latter has also been shown in situations of grave iodine deficiency. In addition to new-born screening directed at early recognition of congenital hypothyroidism (incidence 0.03%), universal screening of all pregnant women should be implemented in health care guidelines. Newly diagnosed overt hypothyroidism in a pregnant woman requires immediate levothyroxine substitution at adequate doses. In subclinical hypothyroidism thyroid hormone replacement should be considered. Iodine supplementation is strongly recommended in all pregnant and breast-feeding women. Pregnancy causes a number of, that need to be of thyroid dysfunction. Both hypothyroidism and thyrotoxicosis may impair the course of pregnancy and may negatively affect the fetus. In particular, maternal hypothyroidism may lead to irreparable and detrimental deficits in the neurocognitive development of the fetus. Autoimmune thyroid disease is the most common cause of thyroid dysfunction in pregnancy. Hashimoto's thyroiditis is associated with impaired fertility and miscarriage, and may first manifest in pregnancy due to the

  2. Comparative genomics reveals a functional thyroid-specific element in the far upstream region of the PAX8 gene

    PubMed Central

    2010-01-01

    Background The molecular mechanisms leading to a fully differentiated thyrocite are still object of intense study even if it is well known that thyroglobulin, thyroperoxidase, NIS and TSHr are the marker genes of thyroid differentiation. It is also well known that Pax8, TTF-1, Foxe1 and Hhex are the thyroid-enriched transcription factors responsible for the expression of the above genes, thus are responsible for the differentiated thyroid phenotype. In particular, the role of Pax8 in the fully developed thyroid gland was studied in depth and it was established that it plays a key role in thyroid development and differentiation. However, to date the bases for the thyroid-enriched expression of this transcription factor have not been unraveled yet. Here, we report the identification and characterization of a functional thyroid-specific enhancer element located far upstream of the Pax8 gene. Results We hypothesized that regulatory cis-acting elements are conserved among mammalian genes. Comparison of a genomic region extending for about 100 kb at the 5'-flanking region of the mouse and human Pax8 gene revealed several conserved regions that were tested for enhancer activity in thyroid and non-thyroid cells. Using this approach we identified one putative thyroid-specific regulatory element located 84.6 kb upstream of the Pax8 transcription start site. The in silico data were verified by promoter-reporter assays in thyroid and non-thyroid cells. Interestingly, the identified far upstream element manifested a very high transcriptional activity in the thyroid cell line PC Cl3, but showed no activity in HeLa cells. In addition, the data here reported indicate that the thyroid-enriched transcription factor TTF-1 is able to bind in vitro and in vivo the Pax8 far upstream element, and is capable to activate transcription from it. Conclusions Results of this study reveal the presence of a thyroid-specific regulatory element in the 5' upstream region of the Pax8 gene. The

  3. [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. PMID:20540354

  4. [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.

  5. Thyroid function in the intensive care unit setting.

    PubMed

    Burman, K D; Wartofsky, L

    2001-01-01

    In sum, there is no convincing evidence yet published supporting the utility of T4 or T3 administration in patients with nonthyroidal illness. The authors recognize that evidence accrued in one disease state may not be applicable to others and that, although these studies are difficult to perform, further large scale prospective studies need to be performed. The issue of T3 treatment will not be resolved satisfactorily until more definitive data are available. Until that time, there may be rare circumstances when a clinician may think it best to treat an individual patient with T4 or T3. For the majority of patients, however, there will be little indication for the administration of thyroid hormones until the potential benefits can be shown to outweigh the risks.

  6. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System.

    PubMed

    Huang, Wen; Xu, Fei; Qu, Tao; Zhang, Rui; Li, Li; Que, Huayong; Zhang, Guofan

    2015-01-01

    Thyroid hormones (THs) play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS) in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR), the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5) was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA). These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3',5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in mollusks contribute

  7. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System.

    PubMed

    Huang, Wen; Xu, Fei; Qu, Tao; Zhang, Rui; Li, Li; Que, Huayong; Zhang, Guofan

    2015-01-01

    Thyroid hormones (THs) play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS) in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR), the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5) was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA). These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3',5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in mollusks contribute

  8. Identification of Thyroid Hormones and Functional Characterization of Thyroid Hormone Receptor in the Pacific Oyster Crassostrea gigas Provide Insight into Evolution of the Thyroid Hormone System

    PubMed Central

    Huang, Wen; Xu, Fei; Qu, Tao; Zhang, Rui; Li, Li; Que, Huayong; Zhang, Guofan

    2015-01-01

    Thyroid hormones (THs) play important roles in development, metamorphosis, and metabolism in vertebrates. During the past century, TH functions were regarded as a synapomorphy of vertebrates. More recently, accumulating evidence has gradually convinced us that TH functions also occur in invertebrate chordates. To date, however, TH-related studies in non-chordate invertebrates have been limited. In this study, THs were qualitatively detected by two reliable methods (HPLC and LC/MS) in a well-studied molluscan species, the Pacific oyster Crassostrea gigas. Quantitative measurement of THs during the development of C. gigas showed high TH contents during embryogenesis and that oyster embryos may synthesize THs endogenously. As a first step in elucidating the TH signaling cascade, an ortholog of vertebrate TH receptor (TR), the most critical gene mediating TH effects, was cloned in C. gigas. The sequence of CgTR has conserved DNA-binding and ligand-binding domains that normally characterize these receptors. Experimental results demonstrated that CgTR can repress gene expression through binding to promoters of target genes and can interact with oyster retinoid X receptor. Moreover, CgTR mRNA expression was activated by T4 and the transcriptional activity of CgTR promoter was repressed by unliganded CgTR protein. An atypical thyroid hormone response element (CgDR5) was found in the promoter of CgTR, which was verified by electrophoretic mobility shift assay (EMSA). These results indicated that some of the CgTR function is conserved. However, the EMSA assay showed that DNA binding specificity of CgTR was different from that of the vertebrate TR and experiments with two dual-luciferase reporter systems indicated that l-thyroxine, 3,3′,5-triiodothyronine, and triiodothyroacetic acid failed to activate the transcriptional activity of CgTR. This is the first study to functionally characterize TR in mollusks. The presence of THs and the functions of CgTR in mollusks

  9. Hematopoietic Stem Cells Transplantation Can Normalize Thyroid Function in a Cystinosis Mouse Model.

    PubMed

    Gaide Chevronnay, H P; Janssens, V; Van Der Smissen, P; Rocca, C J; Liao, X H; Refetoff, S; Pierreux, C E; Cherqui, S; Courtoy, P J

    2016-04-01

    Hypothyroidism is the most frequent and earliest endocrine complication in cystinosis, a multisystemic lysosomal storage disease caused by defective transmembrane cystine transporter, cystinosin (CTNS gene). We recently demonstrated in Ctns(-/-) mice that altered thyroglobulin biosynthesis associated with endoplasmic reticulum stress, combined with defective lysosomal processing, caused hypothyroidism. In Ctns(-/-) kidney, hematopoietic stem cell (HSC) transplantation provides long-term functional and structural protection. Tissue repair involves transfer of cystinosin-bearing lysosomes from HSCs differentiated as F4/80 macrophages into deficient kidney tubular cells, via tunneling nanotubes that cross basement laminae. Here we evaluated the benefit of HSC transplantation for cystinotic thyroid and investigated the underlying mechanisms. HSC engraftment in Ctns(-/-) thyroid drastically decreased cystine accumulation, normalized the TSH level, and corrected the structure of a large fraction of thyrocytes. In the thyroid microenvironment, HSCs differentiated into a distinct, mixed macrophage/dendritic cell lineage expressing CD45 and major histocompatibility complex II but low CD11b and F4/80. Grafted HSCs closely apposed to follicles and produced tunneling nanotube-like extensions that crossed follicular basement laminae. HSCs themselves further squeezed into follicles, allowing extensive contact with thyrocytes, but did not transdifferentiate into Nkx2.1-expressing cells. Our observations revealed significant differences of basement lamina porosity between the thyroid and kidney and/or intrinsic macrophage invasive properties once in the thyroid microenvironment. The contrast between extensive thyrocyte protection and low HSC abundance at steady state suggests multiple sequential encounters and/or remanent impact. This is the first report demonstrating the potential of HSC transplantation to correct thyroid disease and supports a major multisystemic benefit of stem

  10. Various Possible Toxicants Involved in Thyroid Dysfunction: A Review

    PubMed Central

    Bajaj, Jagminder K.; Salwan, Poonam

    2016-01-01

    About 300 million people across the world suffer from thyroid gland dysfunction. Environmental factors play an important role in causation of autoimmune thyroid diseases in susceptible individuals. Genetics contributes to 70% of the risk. In order to reduce the risk, we need to understand the association of environmental agents with thyroid dysfunction. These factors are especially relevant for those at increased risk due to positive family history. The ideal study to see the impact of a thyroid toxicant consists of directly measuring the degree of exposure to toxicant in an individual with his thyroid status. Knowledge of various factors influencing thyroid dysfunction can help in interpreting the results of such studies in a better way. This article is an attempt to highlight the various possible toxicants affecting thyroid function so that adequate measures can be undertaken to control excessive exposure in future to reduce the prevalence of thyroid disorders. PMID:26894086

  11. A Rare Presentation of Autonomously Functioning Papillary Thyroid Cancer: Malignancy in Marine-Lenhart Syndrome Nodule

    PubMed Central

    Uludag, Mehmet; Aygun, Nurcihan; Ozel, Alper; Yener Ozturk, Feyza; Karasu, Rabia; Ozguven, Banu Yilmaz; Citgez, Bulent; Mihmanli, Mehmet; Isgor, Adnan

    2016-01-01

    Objective. Marine-Lenhart Syndrome (MLS) is defined as concomitant occurrence of autonomously functioning thyroid nodule (AFTN) with Graves' disease (GD). Malignancy in a functional nodule is rare. We aimed to present an extremely rare case of papillary thyroid cancer in a MLS nodule with lateral lymph node metastases. Case. A 43-year-old male presented with hyperthyroidism and Graves' ophthalmopathy. On Tc99m pertechnetate scintigraphy, a hyperactive nodule in the left upper thyroid pole was detected and the remaining tissue showed a mildly increased uptake. The ultrasonography demonstrated 15.5 × 13.5 × 12 mm sized hypoechoic nodule in the left upper pole of the thyroid and round lymph nodes on the left side of the neck. Fine needle aspiration biopsy (FNAB) of the nodule and lymph node revealed cytological findings consistent with papillary cancer. Total thyroidectomy with central and left modified radical neck dissection was performed. On pathologic examination, two foci of micropapillary cancer were detected. The skip metastases were present in three lymph nodes on the neck. Conclusion. AFTN can be seen rarely in association with GD. It is not possible to exclude malignancy due to the clinical and imaging findings. In the presence of suspicious clinical and sonographic features, FNAB should be performed. PMID:27110424

  12. Exposure to non-persistent pesticides and thyroid function: A systematic review of epidemiological evidence.

    PubMed

    Campos, Élida; Freire, Carmen

    2016-08-01

    Numerous pesticides are recognized for their endocrine-disrupting properties. Non-persistent pesticides such as organophosphates, dithiocarbamates and pyrethroids may interfere with thyroid function as suggested by animal studies. However, the influence of chronic exposure to these compounds on thyroidal functions in humans remains to be determined. The present study aimed to review epidemiological evidence for an association between exposure to non-persistent pesticides and circulating levels of thyroid hormones (thyroxin [T4] and triiodothyronine [T3]) and thyroid-stimulating hormone (TSH). A systematic review was conducted using MEDLINE, SCOPUS and Virtual Health Library (BVS) databases. Articles were limited to original studies and reports published in English, Portuguese or Spanish. Nineteen epidemiological studies were identified, 17 of which were cross-sectional, 14 were of occupationally exposed workers and 11 used exposure biomarkers. Fungicides and organophosphates (OP) insecticides were the most studied pesticides. Although methodological heterogeneity between studies was noted, particularly regarding study design, exposure assessment, and control of confounding, most of them showed associations with changes in T3 and T4, and/or TSH levels, while results from a few of these are consistent with experimental data supporting the findings that non-persistent pesticide exposure exerts hypothyroid-like effects. However, reporting quality was moderate to poor in 50% of the studies, particularly regarding method of selection of participants and discussion of external validity. Overall, current knowledge regarding the impact of non-persistent pesticides on human thyroid function is still limited. Given the widespread use of pesticides, future research should assess effects of exposure to currently-used pesticides in cohort studies combining comprehensive questionnaire-based assessment and biomarkers. Investigators need to pay particular attention to exposure

  13. Exposure to non-persistent pesticides and thyroid function: A systematic review of epidemiological evidence.

    PubMed

    Campos, Élida; Freire, Carmen

    2016-08-01

    Numerous pesticides are recognized for their endocrine-disrupting properties. Non-persistent pesticides such as organophosphates, dithiocarbamates and pyrethroids may interfere with thyroid function as suggested by animal studies. However, the influence of chronic exposure to these compounds on thyroidal functions in humans remains to be determined. The present study aimed to review epidemiological evidence for an association between exposure to non-persistent pesticides and circulating levels of thyroid hormones (thyroxin [T4] and triiodothyronine [T3]) and thyroid-stimulating hormone (TSH). A systematic review was conducted using MEDLINE, SCOPUS and Virtual Health Library (BVS) databases. Articles were limited to original studies and reports published in English, Portuguese or Spanish. Nineteen epidemiological studies were identified, 17 of which were cross-sectional, 14 were of occupationally exposed workers and 11 used exposure biomarkers. Fungicides and organophosphates (OP) insecticides were the most studied pesticides. Although methodological heterogeneity between studies was noted, particularly regarding study design, exposure assessment, and control of confounding, most of them showed associations with changes in T3 and T4, and/or TSH levels, while results from a few of these are consistent with experimental data supporting the findings that non-persistent pesticide exposure exerts hypothyroid-like effects. However, reporting quality was moderate to poor in 50% of the studies, particularly regarding method of selection of participants and discussion of external validity. Overall, current knowledge regarding the impact of non-persistent pesticides on human thyroid function is still limited. Given the widespread use of pesticides, future research should assess effects of exposure to currently-used pesticides in cohort studies combining comprehensive questionnaire-based assessment and biomarkers. Investigators need to pay particular attention to exposure

  14. Hepatic messenger ribonucleic acid activity profiles in experimental azotemia in the rat. Relationship to food intake and thyroid function.

    PubMed Central

    Kinlaw, W B; Schwartz, H L; Mariash, C N; Bingham, C; Carr, F E; Oppenheimer, J H

    1984-01-01

    We have studied the hepatic messenger RNA (mRNA) activity profile in chronically azotemic rats and sought to determine whether the observed changes could be mediated either by reduced food intake or diminished thyroid function at the tissue level. mRNA activity profiles were produced by two-dimensional gel electrophoretic separation of radioactively labeled products of an in vitro reticulocyte lysate system which had been programmed by hepatic RNA. Of the approximately 240 translational products identified in this system, seven sequences were consistently altered in azotemia. In pair-fed animals six of these also decreased, but the alterations in three were depressed to a significantly lesser extent in the pair-fed group. Moreover, analysis of covariance suggested that food intake could account for the differences in only one sequence. The possibility that the mRNA activity profile in azotemia could represent the effects of diminished thyroid function was minimized by the finding that the reductions in plasma thyroxine (T4) and triiodothyronine (T3) levels observed were due largely to reduced plasma protein binding, with maintenance of the mean free T4 and free T3 concentrations within the normal range. The changes in only one mRNA sequence could be related to free T3 levels alone. Our findings, therefore, indicate that although diminished food intake and reduced thyroid function may contribute to some of the observed changes in the mRNA activity profiles, the bulk of alterations in azotemia appear to be mediated by other mechanisms. The striking overlap between the sequences affected by azotemia and pair-feeding raises the speculation that altered gene expression in azotemia may reflect an impaired hepatic response at the pretranslational level to metabolic signals associated with food intake. Images PMID:6511910

  15. Integrin-linked kinase affects signaling pathways and migration in thyroid cancer cells and is a potential therapeutic target

    PubMed Central

    Shirley, Lawrence A.; McCarty, Samantha; Yang, Ming-Chen; Saji, Motoyasu; Zhang, Xiaoli; Phay, John; Ringel, Matthew D.; Chen, Ching-Shih

    2016-01-01

    Background Integrin-linked kinase (ILK) is a serine-threonine kinase that regulates interactions between the cell and the extracellular matrix. In many cancers, overexpression of ILK leads to increased cell proliferation, motility, and invasion. We hypothesized that ILK functions as a regulator of viability and migration in thyroid cancer cells. Methods Eleven human thyroid cancer cell lines were screened for ILK protein expression. The cell lines with the greatest expression were treated with either ILK small interfering RNA (siRNA) or a novel ILK inhibitor, T315, and the effects were evaluated via Western blot and migration assay. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assays were performed to assess cell viability. Results siRNA against ILK decreased phosphorylation of downstream effectors Akt and MLC, as well as decreased migration. Treatment with T315 showed a dose-related decrease in both Akt and MLC phosphorylation, as well as decreased migration. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assays showed T315 to have an half maximal inhibitory concentration of less than 1 µM in cell lines with high ILK expression. Conclusion ILK is expressed differentially in thyroid cancer cell lines. Both ILK siRNA and T315 inhibit motility of thyroid cancer cell lines, and T315 is shown to be cytotoxic at low concentrations. Altogether, our study suggests that ILK may represent an important kinase in aggressive thyroid cancers. PMID:26549818

  16. The Prevalence of Fragility Fractures in a Population of a Region of Southern Italy Affected by Thyroid Disorders

    PubMed Central

    Notarnicola, Angela; Pesce, Vito; Mudoni, Simona; Tafuri, Silvio; Moretti, Biagio

    2016-01-01

    In the literature there is no clear evidence of a relationship between thyropathies and fragility fractures. The aim of our study is to define the prevalence of thyroid disease in a study sample made up of subjects with fragility fractures and from the same geographical area. We retrospectively studied the “hospital discharge records” (HDR) in the Apulian Database for the period 2008–2013 in order to identify all those patients with fragility fractures that required hospitalization. After detecting the prevalent population, we identified the patients affected by thyroid disease. We observed that, between 2008 and 2013 in Apulia, 16,636 patients were affected by hyperthyroidism. In the same period there were 92,341 subjects with hypothyroidism. The incidence of fragility fractures was 4.5% in the population with hyperthyroidism. As regards the population with hypothyroidism, the incidence of fragility fractures was 3.7%. Furthermore, we assessed the statistical connection between thyroid disease and fragility fractures revealing a higher incidence in patients with hyperthyroidism and clinical hypothyroidism. PMID:27807539

  17. The impacts of thyroid function on the diagnostic accuracy of Cystatin C to detect acute kidney injury in ICU patients: a prospective, observational study

    PubMed Central

    2014-01-01

    Introduction Cystatin C (Cysc) could be affected by thyroid function both in vivo and in vitro and thereby may have limited ability to reflect renal function. We aimed to assess the association between Cysc and thyroid hormones as well as the effect of thyroid function on the diagnostic accuracy of Cysc to detect acute kidney injury (AKI). Methods A total of 446 consecutive intensive care unit (ICU) patients were screened for eligibility in this prospective AKI observational study. Serum Cysc, thyroid hormones and serum creatinine (Scr) were measured upon entry to the ICU. We also collected each patient's baseline characteristics including the Acute Physiology and Chronic Health Evaluation II (APACHE-II) score. The diagnostic performance of Cysc was assessed from the area under the receiver operator characteristic curve (AUC) in each quartile of thyroid hormone(s). Results A total of 114 (25.6%) patients had a clinical diagnosis of AKI upon entry to the ICU. The range of free thyroxine (FT4) value was 4.77 to 39.57 pmol/L. Multivariate linear regression showed that age (standardized beta = 0.128, P < 0.0001), baseline Scr level (standardized beta = 0.290, P < 0.0001), current Scr (standardized beta = 0.453, P < 0.0001), albumin (standardized beta = -0.086, P = 0.006), and FT4 (standardized beta = 0.062, P = 0.039) were related with Cysc. Patients were divided into four quartiles based on FT4 levels. The AUC for Cysc in detecting AKI in each quartile were as follows: 0.712 in quartile I, 0.754 in quartile II, 0.829 in quartile III and 0.797 in quartile IV. There was no significant difference in the AUC between any two groups (all P > 0.05). The optimal cut-off value of Cysc for diagnosing AKI increased across FT4 quartiles (1.15 mg/L in quartile I, 1.15 mg/L in quartile II, 1.35 mg/L in quartile III and 1.45 mg/L in quartile IV). Conclusions There was no significant impact of thyroid function on the diagnostic accuracy

  18. Iodine status and thyroid function among Spanish schoolchildren aged 6-7 years: the Tirokid study.

    PubMed

    Vila, L; Donnay, S; Arena, J; Arrizabalaga, J J; Pineda, J; Garcia-Fuentes, E; García-Rey, C; Marín, J L; Serra-Prat, M; Velasco, I; López-Guzmán, A; Luengo, L M; Villar, A; Muñoz, Z; Bandrés, O; Guerrero, E; Muñoz, J A; Moll, G; Vich, F; Menéndez, E; Riestra, M; Torres, Y; Beato-Víbora, P; Aguirre, M; Santiago, P; Aranda, J; Gutiérrez-Repiso, C

    2016-05-01

    I deficiency is still a worldwide public health problem, with children being especially vulnerable. No nationwide study had been conducted to assess the I status of Spanish children, and thus an observational, multicentre and cross-sectional study was conducted in Spain to assess the I status and thyroid function in schoolchildren aged 6-7 years. The median urinary I (UI) and thyroid-stimulating hormone (TSH) levels in whole blood were used to assess the I status and thyroid function, respectively. A FFQ was used to determine the consumption of I-rich foods. A total of 1981 schoolchildren (52 % male) were included. The median UI was 173 μg/l, and 17·9 % of children showed UI<100 μg/l. The median UI was higher in males (180·8 v. 153·6 μg/l; P<0·001). Iodised salt (IS) intake at home was 69·8 %. IS consumption and intakes of ≥2 glasses of milk or 1 cup of yogurt/d were associated with significantly higher median UI. Median TSH was 0·90 mU/l and was higher in females (0·98 v. 0·83; P<0·001). In total, 0·5 % of children had known hypothyroidism (derived from the questionnaire) and 7·6 % had TSH levels above reference values. Median TSH was higher in schoolchildren with family history of hypothyroidism. I intake was adequate in Spanish schoolchildren. However, no correlation was found between TSH and median UI in any geographical area. The prevalence of TSH above reference values was high and its association with thyroid autoimmunity should be determined. Further assessment of thyroid autoimmunity in Spanish schoolchildren is desirable. PMID:26961225

  19. Young adult reference ranges for thyroid function tests on the Centaur immunoassay analyser.

    PubMed

    Alqahatani, M; Tamimi, W; Aldaker, M; Alenzi, F; Tamim, H; Alsadhan, A

    2006-01-01

    This study aims to establish reference ranges for thyroid tests in young Saudi adults using the Centaur immunoassay method. Physical examination is performed and thyroid function tests include thyroid stimulating hormone (TSH), free thyroxine (FT4) and free triiodothyronine (FT3). These are performed on 291 young Saudi adults (182 [63%] females and 109 [37%] males; average age: 27 years [range 18-50]). Clinical thyroid abnormality, related symptoms and/or abnormal thyroid function tests exclude a person from the study and thus a total of 276 subjects (171 [62%] females and 105 [38%] males) are used to establish the new reference ranges. Combined female and male ranges for TSH, FT4, and FT3 were found to be 0.48-6.30 miu/L (9.00-18.62 pmol/L and 3.39-6.85 pmol/L, respectively). Mean TSH and FT4 levels were significantly different (P<0.0001) from those quoted by the manufacturer. Ranges for TSH were 0.48-6.30 miu/L (female) and 0.52-4.89 miu/L (male) (P=0.08). Female ranges for FT4 and FT3 were 9.00-17.15 pmol/L and 3.39-5.82 pmol/L, respectively. Male ranges were 9.92-18.62 pmol/L (P=0.0001) and 4.36-6.85 pmol/L (P<0.0001). The range of TSH levels in the young local Saudi population proved to be higher than that quoted by the manufacturer. FT4 range was lower and narrower than that quoted by the manufacturer. Significant differences between female and male populations suggest that partitioning of the reference ranges by gender is necessary. PMID:17201204

  20. Change of maternal thyroid function in twin-twin transfusion syndrome.

    PubMed

    Hanaoka, Masachi; Arata, Naoko; Sago, Haruhiko

    2015-01-01

    Human chorionic gonadotropin (hCG) has weak thyroid-stimulating activity because of its homology with thyroid stimulating hormone (TSH). In twin-twin transfusion syndrome (TTTS), which is a severe complication of monochorionic twin pregnancies, a close association between maternal serum hCG concentration and TTTS has been reported. And, TTTS can be treated by fetoscopic laser coagulation of the communicating vessels. To clarify the relationship between maternal serum hCG and maternal thyroid function in TTTS, the present study investigated the change in thyroid hormone and hCG levels after laser therapy. The protocol included collection of serial maternal blood samples in TTTS before laser therapy, and at two and four weeks after laser therapy. For 131 cases of TTTS, the following parameters were determined at each point: hCG, TSH, free triiodothyronine (fT3), and free thyroxine (fT4). The multiple of the median (MoM) of pre-operative hCG concentration in TTTS was 5.39 MoM (interquartile range, 2.83 - 8.64). There was a moderate positive correlation between hCG and fT3 in TTTS pre-operatively (R = 0.22, P = 0.030). fT4 was also positively correlated with hCG (R = 0.33, P < 0.001). Some cases showed very high concentration in fT3. When laser therapy for TTTS was effective, the hCG concentration significantly decreased, and fT3 and fT4 decreased progressively in concert with the decrease in hCG. The relationship between hCG and thyroid function in TTTS supports the finding of TTTS as a novel etiology of hCG-mediated hyperthyroidism during pregnancy. PMID:26194271

  1. Urinary iodine, thyroid function, and thyroglobulin as biomarkers of iodine status.

    PubMed

    Pearce, Elizabeth N; Caldwell, Kathleen L

    2016-09-01

    The accurate assessment of population iodine status is necessary to inform public health policies and clinical research on iodine nutrition, particularly the role of iodine adequacy in normal neurodevelopment. Urinary iodine concentration (UIC) directly reflects dietary iodine intake and is the most common indicator used worldwide to assess population iodine status. The CDC established the Ensuring the Quality of Iodine Procedures program in 2001 to provide laboratories that measure urinary iodine with an independent assessment of their analytic performance; this program fosters improvement in the assessment of UIC. Clinical laboratory tests of thyroid function (including serum concentrations of the pituitary hormone thyrotropin and the thyroid hormones thyroxine and triiodothyronine) are sometimes used as indicators of iodine status, although such use is often problematic. Even in severely iodine-deficient regions, there is a great deal of intraindividual variation in the ability of the thyroid to adapt. In most settings and in most population subgroups other than newborns, thyroid function tests are not considered sensitive indicators of population iodine status. However, the thyroid-derived protein thyroglobulin is increasingly being used for this purpose. Thyroglobulin can be measured in either serum or dried blood spot (DBS) samples. The use of DBS samples is advantageous in resource-poor regions. Improved methodologies for ascertaining maternal iodine status are needed to facilitate research on developmental correlates of iodine status. Thyroglobulin may prove to be a useful biomarker for both maternal and neonatal iodine status, but validated assay-specific reference ranges are needed for the determination of iodine sufficiency in both pregnant women and neonates, and trimester-specific ranges are possibly needed for pregnant women. UIC is currently a well-validated population biomarker, but individual biomarkers that could be used for research, patient care

  2. Thyroid Diseases

    MedlinePlus

    ... of the thyroid gland Hyperthyroidism - when your thyroid gland makes more thyroid hormones than your body needs Hypothyroidism - when your thyroid gland does not make enough thyroid hormones Thyroid cancer ...

  3. Higher Plasma ApoE Levels are Associated with Low-Normal Thyroid Function: Studies in Diabetic and Nondiabetic Subjects.

    PubMed

    van Tienhoven-Wind, L J N; Dallinga-Thie, G M; Dullaart, R P F

    2016-07-01

    Low-normal thyroid function within the euthyroid range may confer higher plasma triglycerides, but relationships with plasma apolipoprotein (apo) E, which plays an important role in the metabolism of triglyceride-rich apoB-containing lipoproteins, are unknown. We determined relationships of plasma apoE with thyroid stimulating hormone (TSH) and free thyroxine (free T4) in euthyroid subjects with and without Type 2 diabetes mellitus (T2DM). TSH, free T4, lipids, and apoE were measured in fasting plasma from 72 T2DM subjects and 82 nondiabetic subjects. The APOE genotype was also determined. Free T4 was slightly higher in T2DM (p=0.030), but TSH levels were not different vs. nondiabetic subjects. The APOE genotype distribution was not different between the groups. None of the participants had the ε2/ε2 genotype. Plasma triglycerides were higher in T2DM (p=0.037). ApoB and apoE levels were not different between the groups. In all subjects combined, multivariable analysis showed that plasma triglycerides (p=0.039), non-high density lipoprotein (non-HDL) cholesterol (p=0.030), and apoE levels (p=0.002) were each independently and positively associated with TSH after adjustment for age, sex, T2DM and the presence of the APOE ε3 allele. Furthermore, the associations of TSH with apoE remained present after adjustment for either triglycerides, non-HDL cholesterol, or apoB (p=0.005 to 0.023). The presence of T2DM did not modify the relationships of TSH with these (apo) lipoprotein variables (p=0.11 to 0.36). In conclusion, low-normal thyroid function, as indicated by higher TSH levels within the euthyroid range, may influence the metabolism of triglyceride-rich lipoproteins by affecting apoE regulation.

  4. [Sex Specificity in Age-Related Thyroid Hormone Responsiveness].

    PubMed

    Suzuki, Satoru

    2016-01-01

    Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for assessment of the thyroid hormone action is the TSH level. Although age and sex are believed to modify the pituitary set point or response to the free thyroid hormone concentration, the precise age- and sex-dependent responses to thyroid hormone have yet to be reported. In this lecture, molecular aspects of resistance to thyroid hormone are initially overviewed. After presentation of the evidence that the TSH-thyroid hormone axis is evolutionarily modified, and that negative feedback mechanisms may start to play roles in homeostatic regulation at the time of delivery, the rationale of age-dependent thyroid hormone resistance is introduced. To assess the age- and sex-dependent resistance to thyroid hormone, the index is provided by the formula based on the relationship between thyroid hormone and TSH levels. The index is calculated by the results of thyroid function tests obtained from the two individual clinical groups. From the results, there were negative relationships between the free T3 resistance index and age in males of both groups, while there were no apparent relationships in females. These findings indicate that there is a male-specific response to thyroid hormone with aging. Furthermore, the specific features of the response may not be affected by environmental factors such as the presence of disorders or medical treatments. PMID:27192800

  5. Impairment of Regulatory T-Cell Function in Autoimmune Thyroid Disease

    PubMed Central

    Glick, Abigail B.; Wodzinski, Alaina; Fu, Pingfu

    2013-01-01

    Background Autoimmune thyroid disease (AITD) pathogenesis may result from a loss of immune tolerance to thyroid antigens. Regulatory T cells (Tregs) control immune responses, prevent excessive inflammation, and may be dysfunctional in AITD. We investigated the role of Tregs in Hashimoto's thyroiditis (HT) and Graves' disease (GD), complicated by Down syndrome (DS). Our goal was to identify differences in CD4+CD25high Treg function or number in patients with GD and HT, compared to healthy controls (HC). Methods Treg number was assessed by flow cytometric analysis in samples from 20 AITD patients (seven GD, 13 HT), nine HC, and seven individuals with DS, a genetic disorder associated with multiple autoimmune disorders including AITD. Treg function was assessed by the inhibition of proliferation (radioactive thymidine incorporation into DNA) of blood-derived T effector (Teff) cells by Tregs in a coculture. Various methods of stimulation were contrasted. Cytokine levels were determined in conditioned media from the co-cultures. Results No differences were found in the frequency of Tregs as a percentage of CD4+ cells between AITD and HC. AITD Tregs were less capable of inhibiting the proliferation of Teff cells when compared to HC; however, the impairment was dependent on the type of stimulation used. DS patients without AITD exhibited normal Treg function. We observed few differences in cytokine production between HC and AITD patients. Conclusions Tregs from AITD patients are partly dysfunctional, possibly explaining their autoimmunity. Future work will elucidate the diagnostic potential and pathophysiology of Tregs in AITD. PMID:23379353

  6. Thyroid Function, Prevalent Coronary Heart Disease, and Severity of Coronary Atherosclerosis in Patients Undergoing Coronary Angiography

    PubMed Central

    Ling, Yan; Jiang, Jingjing; Gui, Minghui; Liu, Lin; Aleteng, Qiqige; Wu, Bingjie; Wang, Shanshan; Liu, Xiaojing; Gao, Xin

    2015-01-01

    This study investigated if free T4 and TSH concentrations or thyroid function categories were associated with prevalent CHD and the severity of coronary atherosclerosis in a population undergoing coronary angiography. This was a cross-sectional study including 1799 patients who were consecutively admitted and underwent coronary angiography. We evaluated the severity of coronary atherosclerosis using Gensini score. In the entire study population, free T4 level was inversely associated with prevalent CHD (OR = 0.95, 95% CI 0.91–0.99, P = 0.01) and the natural log-transformed Gensini score (ln(Gensini score)) (β = −0.03, 95% CI −0.05–−0.01, P = 0.005). The odds of CHD increased gradually across hyperthyroidism, subclinical hypothyroidism, and overt hypothyroidism groups using the euthyroid group as the reference, and the trend is borderline significant (P for trend = 0.051). When comparing to the euthyroid group, ln(Gensini score) of the overt hypothyroidism group was significantly higher (P = 0.009), but the trend was not significant (P for trend = 0.08). A significant association of thyroid function with CHD or ln(Gensini score) in euthyroid patients was not observed. The present study demonstrated an association of thyroid function with prevalent CHD and the severity of coronary atherosclerosis in a population undergoing coronary angiography. However, this association was not observed in euthyroid individuals. PMID:26770196

  7. Thyroid function: comparison of women in late pregnancy with control women of reproductive age in regions of dietary iodine excess.

    PubMed

    Du, Quxiao; Zhu, Hong; Yao, Li

    2013-07-01

    Three hundred pregnant women and 300 women of reproductive age (controls) were selected from regions with a dietary iodine excess to evaluate thyroid and autoimmune thyroid functions. Fasting morning urine and venous blood samples were collected. Urinary iodine concentration, serum free tri-iodothyronine (FT3), free thyroxine (FT4), sensitive thyroid stimulating hormone (sTSH), serum thyroid peroxidase antibody (TPOAb), and thyroglobulin antibody (TGAb) levels were determined. Iodine levels were excessive in 83.7% of pregnant women and 80.7% of the control women. The former showed lower rates of total thyroid disease and subclinical hypothyroidism than the latter (21.7% vs 29.7%, P < 0.05; 19.7% vs 27.3%, P < 0.05). The FT3 level, FT4 level, and TGAb positive rate of pregnant women were lower than that in the controls (P < 0.05). Thus, both excessive iodine intake and pregnancy can influence the thyroid and autoimmune thyroid functions of women.

  8. Opposite variations in maternal and neonatal thyroid function induced by iodine supplementation during pregnancy.

    PubMed

    Nøhr, S B; Laurberg, P

    2000-02-01

    Whereas the consequences of extremes in iodine intake are well described, much less is known about the effect of more moderate variations in maternal iodine intake on fetal thyroid function. The present study performed in Denmark with mild to moderate iodine deficiency dealt with the effect of maternal iodine supplementation on thyroid function in the mother at term and in the fetus/neonate. Serum was collected consecutively from pregnant women at term (n = 144) and from cord blood (n = 139). Forty-nine women had a regular intake of vitamin and mineral tablets with iodine (150 microg/day) during pregnancy, and 95 took no artificial iodine supplementation. Iodine supplementation (+I) induced opposite variations in thyroid function in the mother and the fetus. In +I mothers, TSH was 7.6% lower than in mothers with no supplementation (P < 0.05). In cord blood, on the contrary, TSH was 27.3% higher in the +I group (P < 0.05). The variations were caused by opposite shifts in TSH frequency distribution in mothers and neonates. The association between iodine supplementation and high serum TSH in the neonates was further substantiated by an inverse correlation between thyroglobulin and TSH in cord blood (P < 0.001), whereas no specific pattern was observed in the mothers. High serum thyroglobulin was a marker of low iodine intake in both mothers and neonates. The results suggest that the fetal thyroid, at least in areas of mild iodine deficiency, is more sensitive to the inhibitory effect of iodine than hitherto anticipated.

  9. IL-1β and TSH disturb thyroid epithelium integrity in autoimmune thyroid diseases.

    PubMed

    Rebuffat, Sandra A; Kammoun-Krichen, Maha; Charfeddine, Ilhem; Ayadi, Hammadi; Bougacha-Elleuch, Noura; Peraldi-Roux, Sylvie

    2013-03-01

    Pro-inflammatory cytokines such as IL-1β and TNFα are known to affect thyroid function. They stimulate IL-6 secretion and modify epithelium integrity by altering junction proteins. To study the role of cytokines on thyroid epithelia tightness in autoimmune thyroid diseases (AITD), we analyzed the expression profiles of junction proteins (ZO-1, Claudin, JAM-A) and cytokines in human thyroid slices and also investigated the effect of IL-1β on the epithelium integrity in primary cultures of human thyrocytes. Junction proteins expression (ZO-1, Claudin, JAM-A) has been analyzed by immunohistochemistry on thyroid slices and by Western blot on membrane proteins extracted from thyrocytes of patients suffering from Graves and Hashimoto diseases. The high expression of junction proteins we found on Graves' disease thyroid slices as well as in cell membrane extracts acknowledges the tightness of thyroid follicular cells in this AITD. In contrast, the reduced expression of JAM and ZO-1 in thyroid cells from patients suffering from Hashimoto thyroiditis is in agreement with the loss of thyroid follicular cell integrity that occurs in this pathology. Concerning the effects on epithelium integrity of TSH and of the pro-inflammatory cytokine IL-1β in primary cultures of human thyroid cells, TSH appeared able to modify JAM-A localization but without any change in the expression levels of JAM-A, Claudin and ZO-1. Inversely, IL-1β provoked a decrease in the expression of- and a redistribution of both, Claudin and ZO-1 without modifying the expression and sub-cellular distribution patterns of JAM-A in thyroid cells. These results demonstrate (i) that Hashimoto's- and Graves' diseases display different junction proteins expression patterns with a loss of epithelium integrity in the former and (ii) that IL-1β modifies thyroid epithelial tightness of human thyrocytes by altering the expression and localization of junction proteins. Therefore, IL-1β could play a role in the

  10. [Thyroxine (T4) and tri-iodothyronine (T3) determinations: techniques and value in the assessment of thyroid function].

    PubMed

    Sapin, R; Schlienger, J-L

    2003-01-01

    Hormonal production of the thyroid gland is constituted of thyroxine or T4 (80%) and triiodothyronine or T3 (20%). In the circulation, whole T4 originates from thyroid secretion but most of T3 (80%) is produced extrathyroidally from T4 deiodination. Conversion of T4 to T3 may be influenced by various conditions and circulating T3 is a less reliable reflection of thyroid hormone production than T4. In serum most of T4 and T3 is bound to binding proteins and only 0.02% of T4 and 0.3% of T3 is free. Because of their higher diagnostic performance, free T4 (FT4) and free T3 (FT3) measurements have superseded total (free + bound) hormone determination. Total hormone measurements remain useful for research studies or in case of severe hyperthyroidism. Equilibrium dialysis/RIA is considered as the reference method for free hormone measurements. Routine clinical laboratories use automated direct two-step or one-step immunoassays with a high molecular weight ligand or labelled antibody. Free hormone measurement remains technically demanding, especially in sera from severe non-thyroid ill patients with low serum thyroxine binding capacity. Interference from anti-thyroid hormone antibodies and familial dysalbuminemic hyperthyroxinemia depends on the assay method, but is now less marked and less frequently detected. To be able to correctly interpret the results of an assay, it is necessary to assess its performance in biologically and clinically well-characterised serum samples. FT4, and FT3 measurements, if FT4 is normal and hyperthyroidism suspected, are used to confirm and assess the level of hypo and hyperthyroidism (overt or subclinical). When the thyroidal status is unstable (first months of a thyroid treatment, altered L-T4 dose, subacute thyroiditis) or when the hypothalamic-pituitary function is disturbed (central hypothyroidism), TSH determination is diagnostically misleading and only free hormone measurements are reliable for thyroid function assessment.

  11. Interaction between organophosphate pesticide exposure and PON1 activity on thyroid function

    SciTech Connect

    Lacasana, Marina; Lopez-Flores, Inmaculada; Rodriguez-Barranco, Miguel; Aguilar-Garduno, Clemente; Blanco-Munoz, Julia; Perez-Mendez, Oscar; Gamboa, Ricardo; Gonzalez-Alzaga, Beatriz; Bassol, Susana; Cebrian, Mariano E.

    2010-11-15

    Organophosphate pesticides are widely used in agricultural purposes. Recently, a few studies have demonstrated the ability of these chemicals to alter the function of the thyroid gland in human. Moreover, the paraoxonase-1 enzyme (PON1) plays an important role in the toxicity of some organophosphate pesticides, with low PON1 activity being associated with higher pesticide sensitivity. This study evaluates the interaction between exposure to organophosphate compounds and PON1 enzyme activity on serum levels of TSH and thyroid hormones in a population of workers occupationally exposed to pesticides. A longitudinal study was conducted on a population of floriculture workers from Mexico, during two periods of high and low-intensity levels of pesticide application. A structured questionnaire was completed by workers containing questions on sociodemographic characteristics and other variables of interest. Urine and blood samples were taken, and biomarkers of exposure (dialkylphosphates), susceptibility (PON1 polymorphisms and activity) and effect (thyroid hormone levels) were determined. Interaction between dialkylphosphates and PON1 polymorphisms or PON1 activity on hormone levels was evaluated by generalized estimating equation (GEE) models. A significant interaction was found between serum diazoxonase activity and total dialkylphosphates ({Sigma}DAP) on TSH levels. Thus, when PON1 activity was increased we observed a decrease in the percentage of variation of TSH level for each increment in one logarithmic unit of the {Sigma}DAP levels. This interaction was also observed with the PON1{sub 192}RR genotype. These results suggest a stronger association between organophosphate pesticides and thyroid function in individuals with lower PON1 activity.

  12. Modeling mixtures of thyroid gland function disruptors in a vertebrate alternative model, the zebrafish eleutheroembryo

    SciTech Connect

    Thienpont, Benedicte; Barata, Carlos; Raldúa, Demetrio

    2013-06-01

    Maternal thyroxine (T4) plays an essential role in fetal brain development, and even mild and transitory deficits in free-T4 in pregnant women can produce irreversible neurological effects in their offspring. Women of childbearing age are daily exposed to mixtures of chemicals disrupting the thyroid gland function (TGFDs) through the diet, drinking water, air and pharmaceuticals, which has raised the highest concern for the potential additive or synergic effects on the development of mild hypothyroxinemia during early pregnancy. Recently we demonstrated that zebrafish eleutheroembryos provide a suitable alternative model for screening chemicals impairing the thyroid hormone synthesis. The present study used the intrafollicular T4-content (IT4C) of zebrafish eleutheroembryos as integrative endpoint for testing the hypotheses that the effect of mixtures of TGFDs with a similar mode of action [inhibition of thyroid peroxidase (TPO)] was well predicted by a concentration addition concept (CA) model, whereas the response addition concept (RA) model predicted better the effect of dissimilarly acting binary mixtures of TGFDs [TPO-inhibitors and sodium-iodide symporter (NIS)-inhibitors]. However, CA model provided better prediction of joint effects than RA in five out of the six tested mixtures. The exception being the mixture MMI (TPO-inhibitor)-KClO{sub 4} (NIS-inhibitor) dosed at a fixed ratio of EC{sub 10} that provided similar CA and RA predictions and hence it was difficult to get any conclusive result. There results support the phenomenological similarity criterion stating that the concept of concentration addition could be extended to mixture constituents having common apical endpoints or common adverse outcomes. - Highlights: • Potential synergic or additive effect of mixtures of chemicals on thyroid function. • Zebrafish as alternative model for testing the effect of mixtures of goitrogens. • Concentration addition seems to predict better the effect of

  13. 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

  14. Comparative endocrinology of testicular, adrenal and thyroid function in captive Asian and African elephant bulls.

    PubMed

    Brown, Janine L; Somerville, Malia; Riddle, Heidi S; Keele, Mike; Duer, Connie K; Freeman, Elizabeth W

    2007-04-01

    Concentrations of serum testosterone, cortisol, thyroxine (free and total T4), triiodothyronine (free and total T3) and thyroid stimulating hormone (TSH) were measured to assess adrenal and thyroid function as they relate to testicular activity and musth in captive elephants. Blood samples were collected approximately weekly from Asian (n=8) and African (n=12) bulls at seven facilities for periods of 4 months to 9.5 years. Age ranges at study onset were 8-50 years for Asian and 10-21 years for African elephants. Based on keeper logs, seven Asian and three African bulls exhibited behavioral and/or physical (temporal gland secretion, TGS, or urine dribbling, UD) signs of musth, which lasted 2.8+/-2.5 months in duration. Serum testosterone was elevated during musth, with concentrations often exceeding 100 ng/ml. Patterns of testosterone secretion and musth varied among bulls with no evidence of seasonality (P>0.05). Only three bulls at one facility exhibited classic, well-defined yearly musth cycles. Others exhibited more irregular cycles, with musth symptoms often occurring more than once a year. A number of bulls (1 Asian, 9 African) had consistently low testosterone (<10 ng/ml) and never exhibited significant TGS or UD. At facilities with multiple bulls (n=3), testosterone concentrations were highest in the oldest, most dominant male. There were positive correlations between testosterone and cortisol for six of seven Asian and all three African males that exhibited musth (range, r=0.23-0.52; P<0.05), but no significant correlations for bulls that did not (P>0.05). For the three bulls that exhibited yearly musth cycles, TSH was positively correlated (range, r=0.22-0.28; P<0.05) and thyroid hormones (T3, T4) were negatively correlated (range, r=-0.25 to -0.47; P<0.05) to testosterone secretion. In the remaining bulls, there were no clear relationships between thyroid activity and musth status. Overall mean testosterone and cortisol concentrations increased with age

  15. Functional analysis of a proline to serine mutation in codon 453 of the thyroid hormone receptor {beta}1 gene

    SciTech Connect

    Ozata, M.; Suzuki, Satoru; Takeda, Teiji

    1995-10-01

    Mutations in the gene encoding human thyroid hormone receptor {beta}(hTR{beta}) have been associated with generalized resistance to thyroid hormone (GRTH). This disorder is associated with significant behavoral abnormalities. We examined the hTR{beta} gene in a family with members who manifest inappropriately normal TSH, elevated free T{sub 4}, and free and total T{sub 3}. Sequence analysis showed a cytosine to thymine transition at nucleotide 1642 in one allele of the index patient`s genomic DNA. This altered proline to serine at codon 453. The resulting mutant receptor when expressed in vitro bound DNA with high affinity, but the T{sub 3} affinity of the receptor was impaired. The mutant TR demonstrated a dominant negative effect when cotransfected with two isoforms of wild-type receptor and also in the presence of TR variant {alpha}2 in COS-1 cells. Mutations of codon 453 occur more frequently than at other sites, and four different amino acid substitutions have been reported. Significant differences in phenotype occur among affected individuals, varying from normality to moderately severe GRTH. There is no clear correlation between K{sub a} or in vitro function of the mutant receptor, and phenotype. This study extends the association between GRTH and illness, and indicates that early diagnosis and counseling are needed in families with TR{beta}1 abnormalities. 34 refs., 5 figs., 2 tabs.

  16. Thyroid Hormone and Vascular Remodeling.

    PubMed

    Ichiki, Toshihiro

    2016-01-01

    Both hyperthyroidism and hypothyroidism affect the cardiovascular system. Hypothyroidism is known to be associated with enhanced atherosclerosis and ischemic heart diseases. The accelerated atherosclerosis in the hypothyroid state has been traditionally ascribed to atherogenic lipid profile, diastolic hypertension, and impaired endothelial function. However, recent studies indicate that thyroid hormone has direct anti-atherosclerotic effects, such as production of nitric oxide and suppression of smooth muscle cell proliferation. These data suggest that thyroid hormone inhibits atherogenesis through direct effects on the vasculature as well as modification of risk factors for atherosclerosis. This review summarizes the basic and clinical studies on the role of thyroid hormone in vascular remodeling. The possible application of thyroid hormone mimetics to the therapy of hypercholesterolemia and atherosclerosis is also discussed. PMID:26558400

  17. Thyroid Hormone Treatment

    MedlinePlus

    ... is to closely replicate normal thyroid functioning. Pure, synthetic thyroxine (T4) works in the same way as ... needing thyroid hormone replacement (see Hypothyroidism brochure ). Pure synthetic thyroxine (T4), taken once daily by mouth, successfully ...

  18. Simple, rapid zebrafish larva bioassay for assessing the potential of chemical pollutants and drugs to disrupt thyroid gland function.

    PubMed

    Raldúa, Demetrio; Babin, Patrick J

    2009-09-01

    Thyroid function may be altered by a very large number of chemicals routinely found in the environment Research evaluating potential thyroid disruption is ongoing, but there are thousands of synthetic and naturally occurring drugs and chemicals to be considered. European and United States policies call for the development of simple methodologies for screening endocrine-disrupting chemicals. Zebrafish are widely used as a model organism for assessing drug effects because of their small size, high fecundity, rapid organogenesis, morphological and physiological similarities to mammals, and easewithwhich large-scale phenotypic screening is performed. A zebrafish-based short-duration screening method was developed to detect the potential effect of chemicals and drugs on thyroid function. This method used a T4 immunofluorescence quantitative disruption test (TIQDT) to measure thyroid function. The 3 day exposure window protocol, from day 2 to day 5 postfertilization (dpf), avoided any potential side effects on thyroid gland morphogenesis. Methimazole, propylthiouracil, and potassium perchlorate, three well-known goitrogens, totally abolished T4 immunoreactivity in thyroid follicles in a dose-specific manner. Amiodarone, a human pharmaceutical with a reported cytotoxic effect on thyroid follicular cells, also decreased T4 levels. Moreover, exposure to 50 nM 3,3',5-triiodothyronine induced a significant decrease in T4 immunoreactivity as did DDT, 2,4-D, and 4-nonylphenol. In conclusion, these data indicated that TIQDT may be useful for obtaining initial information about the ability of environmental pollutants and drugs to impair thyroid gland function as well as assessing the combined effects of endocrine disruptors. PMID:19764258

  19. 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.

  20. Thyroid-stimulating hormone receptor levels and binding affinity in the thyroid gland of growth-retarded mice.

    PubMed

    Kobayashi, Kenichi; Sato, Mirei; Machida, Takeo; Kobayashi, Tetsuya

    2005-09-01

    Growth-retarded (grt/grt) mice are congenitally primary hypothyroid. Our previous study indicated that thyroid-stimulating hormone (TSH) responsiveness was defective in the grt/grt thyroid gland. We now report additional studies of impaired grt/grt thyroid function. Semiquantitative RT-PCR confirmed that TSH receptor (TSHR) mRNA expression in the grt/grt thyroid was significantly decreased compared with +/+ thyroids. Scatchard analysis revealed that grt/grt and +/+ mice have only one type of TSH binding site. grt/grt thyroids had fewer TSH binding sites, although this did not apparently affect the affinity of TSH for its receptor. The present data suggest that reduced TSHR levels or defects in TSHR signaling could be one of the possible defective sites in the grt/grt thyroid gland.

  1. Thyroid disease and pregnancy.

    PubMed

    Becks, G P; Burrow, G N

    1991-01-01

    Thyroid disease is common in younger women and may be a factor in reproductive dysfunction. This probably only applies to severe cases of hyper- or hypothyroidism. Once adequately treated, neither of these disorders significantly impacts on fertility. The key is to recognize and to treat thyroid disorders in the reproductive-age woman before conception. Thyroxine therapy and even antithyroid drug therapy should be continued during pregnancy as necessary. Pregnancy is a euthyroid state that is normally maintained by complex changes in thyroid physiology. The fetal and neonatal hypothalamic-pituitary-thyroid system develops independently, but it may be influenced by thyroid disease in the mother. Early pregnancy is characterized by an increase in maternal T4 secretion stimulated by hCG and an increase in TBG, resulting in the elevated total serum T4 in pregnancy. The debate continues as to whether maternal T4 is important in early or late fetal brain development. If so, the physiologic changes in thyroid hormone secretion and transport in early pregnancy would help to ensure that a sufficient amount of thyroid hormone was available. There is new evidence in human subjects that substantial maternal T4 can cross the placenta during pregnancy, and this may be particularly important when fetal thyroid function is compromised as a result of congenital hypothyroidism. Maternal and fetal/neonatal outcomes in pregnancy are adversely affected if severe hypothyroidism is undiagnosed or inadequately treated. Thyroid function tests should be obtained during gestation in women taking T4 and appropriate dose adjustments should be made for TSH levels outside a normal range. The TSH-receptor blocking antibodies from the mother are a recognized cause of congenital hypothyroidism in the fetus and neonate that can be permanent or transient. If neonatal hypothyroidism is detected through neonatal screening programs, and prompt and adequate T4 replacement therapy is instituted as soon as

  2. [Changes in thyroid function in primary degenerative dementia processes].

    PubMed

    Bilikiewicz, A; Bidzan, L

    1989-01-01

    To overcome diagnostic uncertainties in early phases of Alzheimer's disease (pre-senile dementia), the analysis of T-3 and T-4 concentration can be usefully employed. Arising out of the localisation neuropathological findings in Alzheimer type dementia, it could be that hormonal findings perform a useful function as indicators of a change in neurotransmitter activity in this disease. PMID:2704767

  3. Effect of yogic exercises on thyroid function in subjects resident at sea level upon exposure to high altitude

    NASA Astrophysics Data System (ADS)

    Rawal, S. B.; Singh, M. V.; Tyagi, A. K.; Selvamurthy, W.; Chaudhuri, B. N.

    1994-03-01

    Using radioactive iodine, the effect of 1 month's yogic exercises has been investigated on the thyroid function of subjects resident at sea level (SL) specially after their exposure to high altitude (HA). The results have been compared with a group of SL subjects who underwent physical training (PT) exercises for the same duration. Ten healthy male volunteers in the age range of 20 30 years were used as test subjects in this study with each serving as his own control. The subjects were randomly divided into two groups of 5 each. One group practised hatha yogic exercises, while the other group performed the regular PT exercises. The thyroidal accumulation and release of radioactive iodine have been measured in each of the subjects of both groups before and after 1 month of their respective exercises at SL. One month of yogic exercises at SL has been observed to cause a significant reduction in the trans-thy-roidal availability of radioiodine. The thyroid radioactivity in this group of subjects was always below normal levels with the exception of two peaks of radioactive iodine uptake, when the levels of radioactivity in the thyroid were similar to the control values of pre-yogic exercises. The release of radiolabel at 24 48 h was significantly increased after yogic exercises. In contrast, the subjects performing PT exercises for the same duration at SL showed significant thyroid uptake of radioactive iodine at 24 h. Subsequently their131I uptake continued to rise slowly until 72 h without any demonstrable thyroidal release of radiolabel. This indicated that increased thyroid activity was induced by conventional PT exercise. Exposure of SL residents to HA irrespective of their exercise regime altered the thyroidal handling of radioiodine. Thyroidal concentrations of freshly administered radioiodine at early and late sampling intervals were very high in both of the groups, especially the yogics, after their return to SL from HA. Possible mechanisms of the observed

  4. Functional polymorphisms in antioxidant genes in Hurthle cell thyroid neoplasm - an association of GPX1 polymorphism and recurrent Hurthle cell thyroid carcinoma

    PubMed Central

    Goricar, Katja; Gazic, Barbara; Dolzan, Vita; Besic, Nikola

    2016-01-01

    Abstract Background Hurthle cells of the thyroid gland are very rich in mitochondria and oxidative enzymes. As a high level oxidative metabolism may lead to higher level of oxidative stress and can be associated with an increased risk for cancer, we investigated whether common functional polymorphisms in antioxidant genes (SOD2, CAT, GPX, GSTP1, GSTM1 and GSTT1) are associated with the development or clinical course of Hurthle cell thyroid carcinoma (HCTC). Methods A retrospective study was performed in 139 patients treated by thyroid surgery for a Hurthle cell neoplasm. HCTC, Hurthle cell thyroid adenoma (HCTA) or Hurthle cell thyroid nodule (HCTN) were diagnosed by pathomorphology. DNA was extracted from cores of histologically confirmed normal tissue obtained from formalin-fixed paraffin-embedded specimens and genotyped for investigated polymorphisms. Logistic regression was used to compare genotype distributions between patient groups. Results HCTC, HCTA and HCTN were diagnosed in 53, 47 and 21 patients, respectively. Metastatic disease and recurrence of HCTC were diagnosed in 20 and 16 HCTC patients, respectively. Genotypes and allele frequencies of investigated polymorphisms did not deviate from Hardy-Weinberg equilibrium in patients with HCTC, HCTA and HCTN. Under the dominant genetic model we observed no differences in the genotype frequency distribution of the investigated polymorphisms when the HCTA and HCTN group was compared to the HCTC group for diagnosis of HCTC or for the presence of metastatic disease. However, GPX1 polymorphism was associated with the occurrence of recurrent disease (p = 0.040). Conclusions GPX1 polymorphism may influence the risk for recurrent disease in HCTC. PMID:27679545

  5. Functional polymorphisms in antioxidant genes in Hurthle cell thyroid neoplasm - an association of GPX1 polymorphism and recurrent Hurthle cell thyroid carcinoma

    PubMed Central

    Goricar, Katja; Gazic, Barbara; Dolzan, Vita; Besic, Nikola

    2016-01-01

    Abstract Background Hurthle cells of the thyroid gland are very rich in mitochondria and oxidative enzymes. As a high level oxidative metabolism may lead to higher level of oxidative stress and can be associated with an increased risk for cancer, we investigated whether common functional polymorphisms in antioxidant genes (SOD2, CAT, GPX, GSTP1, GSTM1 and GSTT1) are associated with the development or clinical course of Hurthle cell thyroid carcinoma (HCTC). Methods A retrospective study was performed in 139 patients treated by thyroid surgery for a Hurthle cell neoplasm. HCTC, Hurthle cell thyroid adenoma (HCTA) or Hurthle cell thyroid nodule (HCTN) were diagnosed by pathomorphology. DNA was extracted from cores of histologically confirmed normal tissue obtained from formalin-fixed paraffin-embedded specimens and genotyped for investigated polymorphisms. Logistic regression was used to compare genotype distributions between patient groups. Results HCTC, HCTA and HCTN were diagnosed in 53, 47 and 21 patients, respectively. Metastatic disease and recurrence of HCTC were diagnosed in 20 and 16 HCTC patients, respectively. Genotypes and allele frequencies of investigated polymorphisms did not deviate from Hardy-Weinberg equilibrium in patients with HCTC, HCTA and HCTN. Under the dominant genetic model we observed no differences in the genotype frequency distribution of the investigated polymorphisms when the HCTA and HCTN group was compared to the HCTC group for diagnosis of HCTC or for the presence of metastatic disease. However, GPX1 polymorphism was associated with the occurrence of recurrent disease (p = 0.040). Conclusions GPX1 polymorphism may influence the risk for recurrent disease in HCTC.

  6. Ectopic goitrous submandibular thyroid with goitrous orthotopic thyroid gland.

    PubMed

    Bhardwaj, Avinash Kumar; Mani, Vinayaga; Dixit, Rashmi; Garg, Anju

    2016-01-01

    Ectopic thyroid is a rare developmental anomaly with lingual thyroid accounting for majority of the cases. The presence of ectopic thyroid tissue lateral to the midline is very rare, and very few cases located in the submandibular region have been reported. The simultaneous finding of submandibular ectopic thyroid tissue and a functional orthotopic thyroid gland is even rarer. In the differential diagnosis of an ectopic submandibular thyroid, it is fundamental to exclude a metastasis from well-differentiated thyroid cancer, even when primary thyroid carcinoma is not demonstrable.

  7. Ectopic goitrous submandibular thyroid with goitrous orthotopic thyroid gland.

    PubMed

    Bhardwaj, Avinash Kumar; Mani, Vinayaga; Dixit, Rashmi; Garg, Anju

    2016-01-01

    Ectopic thyroid is a rare developmental anomaly with lingual thyroid accounting for majority of the cases. The presence of ectopic thyroid tissue lateral to the midline is very rare, and very few cases located in the submandibular region have been reported. The simultaneous finding of submandibular ectopic thyroid tissue and a functional orthotopic thyroid gland is even rarer. In the differential diagnosis of an ectopic submandibular thyroid, it is fundamental to exclude a metastasis from well-differentiated thyroid cancer, even when primary thyroid carcinoma is not demonstrable. PMID:27413274

  8. 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.

  9. Ectopic goitrous submandibular thyroid with goitrous orthotopic thyroid gland

    PubMed Central

    Bhardwaj, Avinash Kumar; Mani, Vinayaga; Dixit, Rashmi; Garg, Anju

    2016-01-01

    Ectopic thyroid is a rare developmental anomaly with lingual thyroid accounting for majority of the cases. The presence of ectopic thyroid tissue lateral to the midline is very rare, and very few cases located in the submandibular region have been reported. The simultaneous finding of submandibular ectopic thyroid tissue and a functional orthotopic thyroid gland is even rarer. In the differential diagnosis of an ectopic submandibular thyroid, it is fundamental to exclude a metastasis from well-differentiated thyroid cancer, even when primary thyroid carcinoma is not demonstrable. PMID:27413274

  10. Thyroid inferno.

    PubMed

    Bhargava, Amit; Kaur, Manmeet

    2014-01-01

    The key to uncovering the etiology of hyperthyroidism lies in a careful history and physical examination. Autoimmune markers provide additive information, but should not solely be used to make a diagnosis. Concern has been raised that the overzealous use of thyroid ultrasound, following abnormal thyroid function tests, diverts attention from the workup of the biochemical abnormality to the workup of an incidentally found thyroid nodule. If further imaging is needed, the use ofathyroidscanhas been suggestedbythe Endocrine Society and the American Association of Clinical Endocrinologists. However, in certain scenarios, this may be contraindicated. We present the case of a 28-year-old female with hyperthyroidism, as aplatform to discuss an important clinical sign present on Doppler ultrasound of the thyroid. By recognizing the clinical information gained from a Doppler ultrasound, physicians can avoid additional invasive workup and apply the use of ultrasound where most appropriate.

  11. Thyroid Disorders and Diabetes Mellitus

    PubMed Central

    Hage, Mirella; Zantout, Mira S.; Azar, Sami T.

    2011-01-01

    Studies have found that diabetes and thyroid disorders tend to coexist in patients. Both conditions involve a dysfunction of the endocrine system. Thyroid disorders can have a major impact on glucose control, and untreated thyroid disorders affect the management of diabetes in patients. Consequently, a systematic approach to thyroid testing in patients with diabetes is recommended. PMID:21785689

  12. Predictive Modeling of a Mixture of Thyroid Hormone Disrupting Chemicals that Affect Production and Clearance of Thyroxine

    EPA Science Inventory

    Thyroid hormone (TH) disrupting compounds interfere with both thyroidal and extrathyroidal mechanisms to decrease circulating thyroxine (T4). This research tested the hypothesis that serum T4 concentrations of rodents exposed to a mixture of both TH synthesis inhibitors (pesticid...

  13. N-3 polyunsaturated fatty acids supplementation does not affect changes of lipid metabolism induced in rats by altered thyroid status.

    PubMed

    Rauchová, H; Vokurková, M; Pavelka, S; Behuliak, M; Tribulová, N; Soukup, T

    2013-07-01

    Epidemiological studies have demonstrated that n-3 polyunsaturated fatty acid (PUFA) consumption is associated with a reduced risk of atherosclerosis and hyperlipidemia. It is well known that lipid metabolism is also influenced by thyroid hormones. The aim of our study was to test whether n-3 PUFA supplementation (200 mg/kg of body weight/day for 6 weeks given intragastrically) would affect lipid metabolism in Lewis male rats with altered thyroid status. Euthyroid, hypothyroid, and hyperthyroid status of experimental groups was well defined by plasma levels of triiodothyronine, the activity of liver mitochondrial glycerol-3-phosphate dehydrogenase, and by relative heart weight. Fasting blood glucose levels were significantly higher in the hyperthyroid compared to the euthyroid and hypothyroid rats (5.0±0.2 vs. 3.7±0.4 and 4.4±0.2 mmol/l, respectively). In hyperthyroid animals, the concentration of plasma postprandial triglycerides was also increased compared to euthyroid and hypothyroid rats (0.9±0.1 vs. 0.5±0.1 and 0.4±0.1 mmol/l, respectively). On the other hand, hypothyroidism compared to euthyroid and hyperthyroid status was associated with elevated plasma levels of total cholesterol (2.6±0.2 vs. 1.5±0.1 and 1.6±0.1 mmol/l, respectively), LDL cholesterol (0.9±0.1 vs. 0.4±0.1 and 0.2±0.1 mmol/l, respectively) as well as HDL cholesterol (1.6±0.1 vs. 1.0±0.1 and 1.3±0.1 mmol/l, respectively). Supplementation of n-3 PUFA in the present study did not significantly modify either relative heart weight or glucose and lipid levels in any thyroid status.

  14. Overexpression of collagen XIII in extraocular fat affected by active thyroid-associated ophthalmopathy: A crucial piece of the puzzle?

    PubMed

    Morris, Olivia Claire; Schebitz Walter, Kirsten; Telemo, Esbjörn; Hintschich, Christoph

    2016-08-01

    Thyroid-associated ophthalmopathy (TAO) causes irreversible increase in extraocular fat volume that contributes to the risk of exophthalmos and compressive optic neuropathy. Collagen XIII is implicated in uncontrolled cell growth in some tumours, but we are not aware of any studies of collagen XIII in TAO-affected solid tissue to date. We conducted immunohistochemical staining for collagen XIII alpha 1 (COL13A1), present in both the transmembrane and cleaved forms of collagen XIII, in consecutive prospectively collected human extraocular tissue specimens from patients with TAO and controls. We identified overexpression of collagen XIII in active TAO-affected fat. We discuss how species and cell-type specific responses of collagen XIII to stressors may help explain the different phenotypes of TAO. PMID:27245701

  15. 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

  16. 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

  17. Effect of the antioxidant dibunol on adrenocortical, thyroid, and adenohypopyseal function in adult and old rats

    SciTech Connect

    Gorban', E.N.

    1986-04-01

    This paper studies the effect of dibunol (4-methyl-2,6-di-tert-butylphenol) (D) on the function of the adrenal cortex, thyroid gland, and adenhypophysis, which produces trophic hormones for the other two glands. Experiments were carried out on adult rats. After injection of D concentrations of corticosterone (CS), triodothyronine (T/sub 3/), ACTH, and thyrotrophin (TSH) in the blood plasma and the CS concentration in tssue of the adenohypophysis were determined. It is shown that injection of D caused biphasic changes in the CS concentration in both tissues studied in adult and old animals.

  18. Follicular carcinoma of the thyroid with functioning metastases and clinical hyperthyroidism.

    PubMed Central

    McConnon, J. K.; von Westarp, C.; Mitchell, R. I.

    1975-01-01

    Hyperthyroidism associated with metastatic follicular carcinoma of the thyroid gland is rare. In one patient the mass of functioning follicular tissue in the primary and metastatic tumour was so great that excessive amounts of thyroxine and triiodothyronine were produced and, as a result, clinical hyperthyroidism developed. This was in spite of the fact that the activity per unit of tissue was not supranormal and may even have been slightly subnormal. The initial response of the metastases to 131I ablative therapy was excellent. Images FIG. 1 FIG. 2 FIG. 3A FIG. 3B FIG. 4 FIG. 5 PMID:1122444

  19. Synergic actions of polyphenols and cyanogens of peanut seed coat (Arachis hypogaea) on cytological, biochemical and functional changes in thyroid.

    PubMed

    Chandra, Amar K; Mondal, Chiranjit; Sinha, Sabyasachi; Chakraborty, Arijit; Pearce, Elizabeth N

    2015-03-01

    In animals, long-term feeding with peanut (Arachis hypogaea) seed coats causes hypertrophy and hyperplasia of the thyroid gland. However, to date there have been no detailed studies. Here, we explored the thyroidal effects of dietary peanut seed coats (PSC) in rats. The PSC has high levels of pro-goitrogenic substances including phenolic and other cyanogenic constituents. The PSC was mixed with a standard diet and fed to rats for 30 and 60 days, respectively. Animals fed with the PSC-supplemented diet showed a significant increase in urinary excretion of thiocyanate and iodine, thyroid enlargement, and hypertrophy and/or hyperplasia of thyroid follicles. In addition, there was inhibition of thyroid peroxidase (TPO) activity, 5'-deiodinase-I (DIO1) activity, and (Na+-K+)-ATPase activity in the experimental groups of rats as compared to controls. Furthermore, the PSC fed animals exhibited decreased serum circulating total T4 and T3 levels, severe in the group treated for longer duration. These data indicate that PSC could be a novel disruptor of thyroid function, due to synergistic actions of phenolic as well as cyanogenic constituents. PMID:25872244

  20. Synergic actions of polyphenols and cyanogens of peanut seed coat (Arachis hypogaea) on cytological, biochemical and functional changes in thyroid.

    PubMed

    Chandra, Amar K; Mondal, Chiranjit; Sinha, Sabyasachi; Chakraborty, Arijit; Pearce, Elizabeth N

    2015-03-01

    In animals, long-term feeding with peanut (Arachis hypogaea) seed coats causes hypertrophy and hyperplasia of the thyroid gland. However, to date there have been no detailed studies. Here, we explored the thyroidal effects of dietary peanut seed coats (PSC) in rats. The PSC has high levels of pro-goitrogenic substances including phenolic and other cyanogenic constituents. The PSC was mixed with a standard diet and fed to rats for 30 and 60 days, respectively. Animals fed with the PSC-supplemented diet showed a significant increase in urinary excretion of thiocyanate and iodine, thyroid enlargement, and hypertrophy and/or hyperplasia of thyroid follicles. In addition, there was inhibition of thyroid peroxidase (TPO) activity, 5'-deiodinase-I (DIO1) activity, and (Na+-K+)-ATPase activity in the experimental groups of rats as compared to controls. Furthermore, the PSC fed animals exhibited decreased serum circulating total T4 and T3 levels, severe in the group treated for longer duration. These data indicate that PSC could be a novel disruptor of thyroid function, due to synergistic actions of phenolic as well as cyanogenic constituents.

  1. Effects of a series of metalloporphyrins on adrenal, testicular and thyroid function in rats.

    PubMed

    Drummond, G S; Smith, T J; Kappas, A

    1996-03-01

    We have extended our earlier studies [Pharmacology 1986;34:9-16] on the effects of certain synthetic heme analogues and cobalt chloride (CoCl2) on endocrine functions mediated by the hypothalamic-pituitary axis to examine specifically the ability of Sn-protoporphyrin (SnPP) and Sn-mesoporphyrin (SnMP) to perturb adrenal, testicular and thyroid function since there is interest in the use of Sn(tin)-porphyrins in the treatment of hyperbilirubinemia of the newborn. SnPP and SnMP when administered to adult male rats did not alter serum corticosterone, testosterone, thyroxine or triiodothyronine levels when compared to control animals. In addition, administration of exogenous adrenocorticotrophic hormone produced an increase in serum corticosterone levels that was comparable in placebo-treated and SnPP- and SnMP-treated animals. These studies involved doses of both compounds substantially greater than those used clinically. The results clearly indicate that SnMP, presently the compound of choice for use in newborns, and SnPP do not in the doses studied impair adrenal, testicular and thyroid function in vivo.

  2. Effect of thiocyanate levels in milk on thyroid function in iodine deficient subjects.

    PubMed

    Dahlberg, P A; Bergmark, A; Eltom, M; Björck, L; Claesson, O

    1985-05-01

    To utilize the antibacterial effect of the lactoperoxidase system to prevent bacterial spoilage of raw milk it is necessary to increase the thiocyanate concentration of the milk. Thiocyanate has, however, a potent antithyroid effect which is enhanced by iodine deficiency. In this study the thyroid function has been studied, before and after 4 weeks daily administration of 250 ml of such treated milk, in 55 goitrous subjects living in an endemic goiter region of western Sudan. The iodine content was 0.1 mg/l and the thiocyanate content was either 3.6 mg/l (n 19) or 19 mg/l (n 36) in the milk. At the start of the experiment all subjects were iodine deficient with a urinary excretion of 40-50 micrograms/g creatinine. After 4 weeks daily intake of 4.75 mg of thiocyanate by way of milk the serum thiocyanate level increased by approximately 1.7 mg/l. Both at the beginning and at the end of the experimental period the serum levels of thyroxine, triiodothyronine and TSH were in the normal range for all subjects. After 4 weeks the TSH levels had decreased significantly, (from 2.6 +/- 0.2 to 2.1 +/- 0.2 mU/l, p less than 0.001) probably as an effect of the supplementary intake of iodine. The thyroid hormone levels remained unchanged during the experimental period. In conclusion, the intake of milk with an iodine concentration of 0.1 mg/l and a thiocyanate concentration of 19 mg/l does not have a negative effect on the thyroid function in iodine deficient subjects.

  3. 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...

  4. Fluoride caused thyroid endocrine disruption in male zebrafish (Danio rerio).

    PubMed

    Jianjie, Chen; Wenjuan, Xue; Jinling, Cao; Jie, Song; Ruhui, Jia; Meiyan, Li

    2016-02-01

    Excessive fluoride in natural water ecosystem has the potential to detrimentally affect thyroid endocrine system, but little is known of such effects or underlying mechanisms in fish. In the present study, we evaluated the effects of fluoride on growth performance, thyroid histopathology, thyroid hormone levels, and gene expressions in the HPT axis in male zebrafish (Danio rerio) exposed to different determined concentrations of 0.1, 0.9, 2.0 and 4.1 M of fluoride to investigate the effects of fluoride on thyroid endocrine system and the potential toxic mechanisms caused by fluoride. The results indicated that the growth of the male zebrafish used in the experiments was significantly inhibited, the thyroid microtrastructure was changed, and the levels of T3 and T4 were disturbed in fluoride-exposed male fish. In addition, the expressional profiles of genes in HPT axis displayed alteration. The expressions of all studied genes were significantly increased in all fluoride-exposed male fish after exposure for 45 days. The transcriptional levels of corticotrophin-releasing hormone (CRH), thyroid-stimulating hormone (TSH), thyroglobulin (TG), sodium iodide symporter (NIS), iodothyronine I (DIO1), and thyroid hormone receptor alpha (TRα) were also elevated in all fluoride-exposed male fish after 90 days of exposure, while the inconsistent expressions were found in the mRNA of iodothyronineⅡ (DIO2), UDP glucuronosyltransferase 1 family a, b (UGT1ab), transthyretin (TTR), and thyroid hormone receptor beta (TRβ). These results demonstrated that fluoride could notably inhibit the growth of zebrafish, and significantly affect thyroid endocrine system by changing the microtrastructure of thyroid, altering thyroid hormone levels and endocrine-related gene expressions in male zebrafish. All above indicated that fluoride could pose a great threat to thyroid endocrine system, thus detrimentally affected the normal function of thyroid of male zebrafish. PMID:26748264

  5. Fluoride caused thyroid endocrine disruption in male zebrafish (Danio rerio).

    PubMed

    Jianjie, Chen; Wenjuan, Xue; Jinling, Cao; Jie, Song; Ruhui, Jia; Meiyan, Li

    2016-02-01

    Excessive fluoride in natural water ecosystem has the potential to detrimentally affect thyroid endocrine system, but little is known of such effects or underlying mechanisms in fish. In the present study, we evaluated the effects of fluoride on growth performance, thyroid histopathology, thyroid hormone levels, and gene expressions in the HPT axis in male zebrafish (Danio rerio) exposed to different determined concentrations of 0.1, 0.9, 2.0 and 4.1 M of fluoride to investigate the effects of fluoride on thyroid endocrine system and the potential toxic mechanisms caused by fluoride. The results indicated that the growth of the male zebrafish used in the experiments was significantly inhibited, the thyroid microtrastructure was changed, and the levels of T3 and T4 were disturbed in fluoride-exposed male fish. In addition, the expressional profiles of genes in HPT axis displayed alteration. The expressions of all studied genes were significantly increased in all fluoride-exposed male fish after exposure for 45 days. The transcriptional levels of corticotrophin-releasing hormone (CRH), thyroid-stimulating hormone (TSH), thyroglobulin (TG), sodium iodide symporter (NIS), iodothyronine I (DIO1), and thyroid hormone receptor alpha (TRα) were also elevated in all fluoride-exposed male fish after 90 days of exposure, while the inconsistent expressions were found in the mRNA of iodothyronineⅡ (DIO2), UDP glucuronosyltransferase 1 family a, b (UGT1ab), transthyretin (TTR), and thyroid hormone receptor beta (TRβ). These results demonstrated that fluoride could notably inhibit the growth of zebrafish, and significantly affect thyroid endocrine system by changing the microtrastructure of thyroid, altering thyroid hormone levels and endocrine-related gene expressions in male zebrafish. All above indicated that fluoride could pose a great threat to thyroid endocrine system, thus detrimentally affected the normal function of thyroid of male zebrafish.

  6. Interactions between thyroid disorders and kidney disease

    PubMed Central

    Basu, Gopal; Mohapatra, Anjali

    2012-01-01

    There are several interactions between thyroid and kidney functions in each other organ's disease states. Thyroid hormones affect renal development and physiology. Thyroid hormones have pre-renal and intrinsic renal effects by which they increase the renal blood flow and the glomerular filtration rate (GFR). Hypothyroidism is associated with reduced GFR and hyperthyroidism results in increased GFR as well as increased renin – angiotensin – aldosterone activation. Chronic kidney disease (CKD) is characterized by a low T3 syndrome which is now considered a part of an atypical nonthyroidal illness. CKD patients also have increased incidence of primary hypothyroidism and subclinical hypothyroidism. The physiological benefits of a hypothyroid state in CKD, and the risk of CKD progression with hyperthyroidism emphasize on a conservative approach in the treatment of thyroid hormone abnormalities in CKD. Thyroid dysfunction is also associated with glomerulonephritis often by a common autoimmune etiology. Several drugs could affect both thyroid and kidney functions. There are few described interactions between thyroid and renal malignancies. A detailed knowledge of all these interactions is important for both the nephrologists and endocrinologists for optimal management of the patient. PMID:22470856

  7. Cytoskeletal and functional changes in bioreactor assembled thyroid tissue organoids exposed to gamma radiation

    NASA Technical Reports Server (NTRS)

    Green, Lora M.; Patel, Zarana; Murray, Deborah K.; Rightnar, Steven; Burell, Cheryl G.; Gridley, Daila S.; Nelson, Gregory A.

    2002-01-01

    Fischer rat thyroid cells were grown under low-shear stress in a bioreactor to a stage of organization composed of integrated follicles resembling small thyroid glands prior to exposure to 3 Gray-gamma radiation. Bioreactor tissues and controls (both irradiated and non-irradiated) were harvested at 24, 48, 96 and 144 hours post-exposure. Tissue samples were fixed and fluorescently labeled for actin and microtubules. Tissues were assessed for changes in cytoskeletal components induced by radiation and quantified by laser scanning cytometry. ELISA's were used to quantify transforming growth factor-beta and thyroxin released from cells to the culture supernatant. Tissue architecture was disrupted by exposure to radiation with the structural organization of actin and loss of follicular content the most obviously affected. With time post-irradiation the actin appeared disordered and the levels of fluorescence associated with filamentous-actin and microtubules cycled in the tissue analogs, but not in the flask-grown cultures. Active transforming growth factor-beta was higher in supernatants from the irradiated bioreactor tissue. Thyroxin release paralleled cell survival in the bioreactors and control cultures. Thus, the engineered tissue responses to radiation differed from those of conventional tissue culture making it a potentially better mimic of the in vivo situation.

  8. Thyroid function, metabolic indices and growth performance in pigs fed 00-rapeseed meal.

    PubMed

    Svetina, A; Jerković, I; Vrabac, Ljiljana; Curić, S

    2003-01-01

    Thyroid function and morphology, liver morphology, some metabolic indices, haematological parameters and growth performance of fattening pigs fed 00-rapeseed meal (00-RPM) were examined. The control group was fed on a standard diet containing 6% sunflower seed meal (SM) during the growing period and 8% during the finishing period. The first experimental group was fed a diet in which SM was replaced by equal (6% and 8%) amounts of 00-RPM. The second experimental group was fed with a higher (8% and 10%) amount of 00-RPM. There were no significant differences between the control and experimental groups in the serum concentrations of triiodothyronine (T3) and thyroxine (T4). Thyroid gland and liver weights were significantly (P < 0.01) higher in both groups fed 00-RPM than in the group fed SM. The epithelium of the thyroid gland was cuboidal or columnar and the follicular area was moderately enlarged in pigs fed 00-RPM. Marked changes in liver histology were not observed. The 00-RPM diet increased (P < 0.01) the serum values of total proteins in the first fattening period. At the end of fattening both groups fed 00-RPM had higher (P < 0.05; P < 0.01) concentrations of plasma glucose than the control group. The inclusion of 10% of 00-RPM during the finishing period increased (P < 0.05) the serum values of insulin. Daily weight gain during the growing and the finishing period was higher (P < 0.05) in the experimental groups than in the control group. The results suggest that 6-10% 00-RPM can be used as a protein source in the diet of fattening pigs without poisonous side effects.

  9. Modeling mixtures of thyroid gland function disruptors in a vertebrate alternative model, the zebrafish eleutheroembryo.

    PubMed

    Thienpont, Benedicte; Barata, Carlos; Raldúa, Demetrio

    2013-06-01

    Maternal thyroxine (T4) plays an essential role in fetal brain development, and even mild and transitory deficits in free-T4 in pregnant women can produce irreversible neurological effects in their offspring. Women of childbearing age are daily exposed to mixtures of chemicals disrupting the thyroid gland function (TGFDs) through the diet, drinking water, air and pharmaceuticals, which has raised the highest concern for the potential additive or synergic effects on the development of mild hypothyroxinemia during early pregnancy. Recently we demonstrated that zebrafish eleutheroembryos provide a suitable alternative model for screening chemicals impairing the thyroid hormone synthesis. The present study used the intrafollicular T4-content (IT4C) of zebrafish eleutheroembryos as integrative endpoint for testing the hypotheses that the effect of mixtures of TGFDs with a similar mode of action [inhibition of thyroid peroxidase (TPO)] was well predicted by a concentration addition concept (CA) model, whereas the response addition concept (RA) model predicted better the effect of dissimilarly acting binary mixtures of TGFDs [TPO-inhibitors and sodium-iodide symporter (NIS)-inhibitors]. However, CA model provided better prediction of joint effects than RA in five out of the six tested mixtures. The exception being the mixture MMI (TPO-inhibitor)-KClO4 (NIS-inhibitor) dosed at a fixed ratio of EC10 that provided similar CA and RA predictions and hence it was difficult to get any conclusive result. There results support the phenomenological similarity criterion stating that the concept of concentration addition could be extended to mixture constituents having common apical endpoints or common adverse outcomes. PMID:23562343

  10. Thyroid Hormones Are Associated With Cognitive Function: Moderation by Sex, Race, and Depressive Symptoms

    PubMed Central

    Beydoun, H. A.; Kitner-Triolo, M. H.; Kaufman, J. S.; Evans, M. K.; Zonderman, A. B.

    2013-01-01

    Context: Recent evidence indicates that thyroid hormones may be closely linked to cognition among adults. Objective: We investigated associations between thyroid hormones and cognitive performance, while testing effect modification by sex, race, and elevated depressive symptoms (EDS). Design: This cross-sectional study used extensive data from the Healthy Aging in Neighborhoods of Diversity across the Life Span (HANDLS) study. Setting: The study was conducted in Baltimore, Maryland, from 2004 to 2009. Participants: Participants were U.S. adults aged 30 to 64 years. The sample size ranged from 1275 to 1346. Main Outcome Measures: Outcomes included 13 cognitive test scores spanning domains of learning/memory, language/verbal, attention, visuo-spatial/visuo-construction, psychomotor speed, executive function, and mental status. Results: Within reference ranges and after Bonferroni correction, elevated free thyroxine (fT4) was associated with better performance on tests of visuo-spatial/visuo-construction ability (overall, women, and African Americans) and learning/memory (women and African Americans), whereas a higher total thyroxine (tT4) level was associated with better performance in the domain of psychomotor speed (individuals without EDS) and higher levels of both fT4 and tT4 were linked to better language/verbal test performance among men. In contrast, higher T3(% uptake) was related to better performance on tests of visuo-spatial/visuo-construction ability and psychomotor speed among whites. When the above reference range was compared within the overall population and after Bonferroni correction, a within reference range fT4 was linked to better performance on visuo-spatial/visuo-constrution ability and psychomotor speed, whereas a below normal range TSH level (compared with the reference range) was linked to better performance in domains of psychomotor speed and attention. Conclusions: Thyroid hormones and cognition are closely linked differentially by sex

  11. Impact of mild thyroid hormone deficiency in pregnancy on cognitive function in children: lessons from the Generation R Study.

    PubMed

    Ghassabian, Akhgar; Henrichs, Jens; Tiemeier, Henning

    2014-03-01

    Animal models and epidemiological studies suggest that mild maternal thyroid hormone deficiency in early gestation has adverse consequences on the cognitive abilities of the children. However, methodological problems, lack of a consistent definition for mild thyroid hormone deficiency, and short follow-up of the children reduce the confidence in the conclusion of existing studies. In this review, we summarize the main findings of a series of studies performed in Generation R, a population-based birth cohort in Rotterdam, the Netherlands. In this iodine sufficient region, we aimed to investigate the relation between mild maternal thyroid hormone deficiency in early gestation and children's verbal and nonverbal cognitive function and executive function. We discuss the main findings of these studies, present recommendations for clinicians and formulate suggestions for future research. PMID:24629863

  12. Stereology of the Thyroid Gland in Indo-Pacific Bottlenose Dolphin (Tursiops aduncus) in Comparison with Human (Homo sapiens): Quantitative and Functional Implications

    PubMed Central

    Kot, Brian Chin Wing; Lau, Thomas Yue Huen; Cheng, Sammy Chi Him

    2013-01-01

    The mammalian thyroid gland maintains basal metabolism in tissues for optimal function. Determining thyroid volume is important in assessing growth and involution. Volume estimation is also important in stereological studies. Direct measurements of colloid volume and nuclear-to-cytoplasmic ratio of the follicular cells may provide important information about thyroid gland function such as hormone storage and secretion, which helps understand the changes at morphological and functional levels. The present study determined the colloid volume using simple stereological principle and the nuclear-to-cytoplasmic ratio of 4 Indo-Pacific bottlenose dolphins and 2 human thyroid glands. In both dolphin and human thyroid glands, the size of the follicles tended to be quite variable. The distribution of large and small follicles within the thyroid gland was also found to be random in both the dolphin and human thyroid gland; however, the size of follicles appeared to decrease as a function of increasing age in the dolphin thyroid gland. The mean colloid volume of the dolphin thyroid gland and human thyroid gland was 1.22×105 µm3 and 7.02×105 µm3 respectively. The dolphin and human subjects had a significant difference in the mean colloid volume. The mean N/C ratio of the dolphin thyroid follicular epithelia and human follicular epithelia was 0.50 and 0.64 respectively. The dolphin and human subjects had a significant difference in the mean N/C ratio. This information contributes to understanding dolphin thyroid physiology and its structural adaptations to meet the physical demands of the aquatic environment, and aids with ultrasonography and corrective therapy in live subjects. PMID:23690927

  13. Stereology of the thyroid gland in Indo-Pacific bottlenose dolphin (Tursiops aduncus) in comparison with human (Homo sapiens): quantitative and functional implications.

    PubMed

    Kot, Brian Chin Wing; Lau, Thomas Yue Huen; Cheng, Sammy Chi Him

    2013-01-01

    The mammalian thyroid gland maintains basal metabolism in tissues for optimal function. Determining thyroid volume is important in assessing growth and involution. Volume estimation is also important in stereological studies. Direct measurements of colloid volume and nuclear-to-cytoplasmic ratio of the follicular cells may provide important information about thyroid gland function such as hormone storage and secretion, which helps understand the changes at morphological and functional levels. The present study determined the colloid volume using simple stereological principle and the nuclear-to-cytoplasmic ratio of 4 Indo-Pacific bottlenose dolphins and 2 human thyroid glands. In both dolphin and human thyroid glands, the size of the follicles tended to be quite variable. The distribution of large and small follicles within the thyroid gland was also found to be random in both the dolphin and human thyroid gland; however, the size of follicles appeared to decrease as a function of increasing age in the dolphin thyroid gland. The mean colloid volume of the dolphin thyroid gland and human thyroid gland was 1.22×10(5) µm(3) and 7.02×10(5) µm(3) respectively. The dolphin and human subjects had a significant difference in the mean colloid volume. The mean N/C ratio of the dolphin thyroid follicular epithelia and human follicular epithelia was 0.50 and 0.64 respectively. The dolphin and human subjects had a significant difference in the mean N/C ratio. This information contributes to understanding dolphin thyroid physiology and its structural adaptations to meet the physical demands of the aquatic environment, and aids with ultrasonography and corrective therapy in live subjects.

  14. Modelling of Thyroid Peroxidase Reveals Insights into Its Enzyme Function and Autoantigenicity.

    PubMed

    Le, Sarah N; Porebski, Benjamin T; McCoey, Julia; Fodor, James; Riley, Blake; Godlewska, Marlena; Góra, Monika; Czarnocka, Barbara; Banga, J Paul; Hoke, David E; Kass, Itamar; Buckle, Ashley M

    2015-01-01

    Thyroid peroxidase (TPO) catalyses the biosynthesis of thyroid hormones and is a major autoantigen in Hashimoto's disease--the most common organ-specific autoimmune disease. Epitope mapping studies have shown that the autoimmune response to TPO is directed mainly at two surface regions on the molecule: immunodominant regions A and B (IDR-A, and IDR-B). TPO has been a major target for structural studies for over 20 years; however, to date, the structure of TPO remains to be determined. We have used a molecular modelling approach to investigate plausible modes of TPO structure and dimer organisation. Sequence features of the C-terminus are consistent with a coiled-coil dimerization motif that most likely anchors the TPO dimer in the apical membrane of thyroid follicular cells. Two contrasting models of TPO were produced, differing in the orientation and exposure of their active sites relative to the membrane. Both models are equally plausible based upon the known enzymatic function of TPO. The "trans" model places IDR-B on the membrane-facing side of the myeloperoxidase (MPO)-like domain, potentially hindering access of autoantibodies, necessitating considerable conformational change, and perhaps even dissociation of the dimer into monomers. IDR-A spans MPO- and CCP-like domains and is relatively fragmented compared to IDR-B, therefore most likely requiring domain rearrangements in order to coalesce into one compact epitope. Less epitope fragmentation and higher solvent accessibility of the "cis" model favours it slightly over the "trans" model. Here, IDR-B clusters towards the surface of the MPO-like domain facing the thyroid follicular lumen preventing steric hindrance of autoantibodies. However, conformational rearrangements may still be necessary to allow full engagement with autoantibodies, with IDR-B on both models being close to the dimer interface. Taken together, the modelling highlights the need to consider the oligomeric state of TPO, its conformational

  15. Polybrominated Diphenyl Ether Exposure and Thyroid Function Tests in North American Adults

    PubMed Central

    Makey, Colleen M.; McClean, Michael D.; Braverman, Lewis E.; Pearce, Elizabeth N.; He, Xue-Mei; Sjödin, Andreas; Weinberg, Janice M.; Webster, Thomas F.

    2015-01-01

    Background: Polybrominated diphenyl ethers (PBDEs) are flame-retardant chemicals that are added to many consumer products. Multiple animal studies have shown PBDEs to be thyroid hormone (TH) disruptors. Epidemiologic evidence of PBDE exposure associated with TH disruption has been inconclusive. Objectives: We used repeated measures to estimate associations between serum PBDE concentrations and THs in a North American adult cohort. Methods: From 2010 to 2011, we collected ≤ 3 serum samples at approximately 6-month intervals from 52 healthy adult office workers from Boston, Massachusetts, for analysis of PBDE congeners and THs. Results: The geometric mean sum concentrations of the most prevalent PBDE congeners (BDE-28, BDE-47, BDE-99, BDE-100, and BDE-153) were 22 ng/g lipid in winter 2010, 23 ng/g lipid in summer 2010, and 19 ng/g lipid in winter 2011. BDE-47 was the predominant congener. Based on a multivariable mixed regression model, we estimated that on average, a 1-ng/g serum increase in BDE-47 was associated with a 2.6-μg/dL decrease in total thyroxine (T4) (95% CI: –4.7, –0.35). Total T4 was inversely associated with each PBDE congener. Serum concentrations of PBDEs were not strongly associated with total triiodothyronine (T3), free T4, or thyroid-stimulating hormone (TSH). Conclusion: These results are consistent with those from animal studies showing that exposure to PBDEs is associated with a decrease in serum T4. Because the other TH concentrations did not appear to be associated with BDE exposures, our findings do not indicate effects on the pituitary–thyroid axis. Taken together, our findings suggest that PBDE exposure might decrease the binding of T4 to serum T4 binding proteins. Citation: Makey CM, McClean MD, Braverman LE, Pearce EN, He XM, Sjödin A, Weinberg JM, Webster TF. 2016. Polybrominated diphenyl ether exposure and thyroid function tests in North American adults. Environ Health Perspect 124:420–425; http://dx.doi.org/10.1289/ehp

  16. Modelling of Thyroid Peroxidase Reveals Insights into Its Enzyme Function and Autoantigenicity

    PubMed Central

    Fodor, James; Riley, Blake; Godlewska, Marlena; Góra, Monika; Czarnocka, Barbara; Banga, J Paul; Hoke, David E.; Kass, Itamar; Buckle, Ashley M.

    2015-01-01

    Thyroid peroxidase (TPO) catalyses the biosynthesis of thyroid hormones and is a major autoantigen in Hashimoto’s disease—the most common organ-specific autoimmune disease. Epitope mapping studies have shown that the autoimmune response to TPO is directed mainly at two surface regions on the molecule: immunodominant regions A and B (IDR-A, and IDR-B). TPO has been a major target for structural studies for over 20 years; however, to date, the structure of TPO remains to be determined. We have used a molecular modelling approach to investigate plausible modes of TPO structure and dimer organisation. Sequence features of the C-terminus are consistent with a coiled-coil dimerization motif that most likely anchors the TPO dimer in the apical membrane of thyroid follicular cells. Two contrasting models of TPO were produced, differing in the orientation and exposure of their active sites relative to the membrane. Both models are equally plausible based upon the known enzymatic function of TPO. The “trans” model places IDR-B on the membrane-facing side of the myeloperoxidase (MPO)-like domain, potentially hindering access of autoantibodies, necessitating considerable conformational change, and perhaps even dissociation of the dimer into monomers. IDR-A spans MPO- and CCP-like domains and is relatively fragmented compared to IDR-B, therefore most likely requiring domain rearrangements in order to coalesce into one compact epitope. Less epitope fragmentation and higher solvent accessibility of the “cis” model favours it slightly over the “trans” model. Here, IDR-B clusters towards the surface of the MPO-like domain facing the thyroid follicular lumen preventing steric hindrance of autoantibodies. However, conformational rearrangements may still be necessary to allow full engagement with autoantibodies, with IDR-B on both models being close to the dimer interface. Taken together, the modelling highlights the need to consider the oligomeric state of TPO, its

  17. Postpartum Thyroiditis

    MedlinePlus

    ... high thyroid hormone levels in the blood) and hypothyroidism (low thyroid hormone levels in the blood). In postpartum thyroiditis, thyrotoxicosis occurs first followed by hypothyroidism. What causes postpartum thyroiditis? The exact cause is ...

  18. Thyroid Tests

    MedlinePlus

    ... calories and how fast your heart beats. Thyroid tests check how well your thyroid is working. They ... thyroid diseases such as hyperthyroidism and hypothyroidism. Thyroid tests include blood tests and imaging tests. Blood tests ...

  19. Thyroid storm

    MedlinePlus

    Thyrotoxic storm; Hyperthyroid storm; Accelerated hyperthyroidism; Thyroid crisis; Thyrotoxicosis - thyroid storm ... Thyroid storm occurs due to a major stress such as trauma, heart attack , or infection. In rare cases, thyroid ...

  20. GLI1 Transcription Factor Affects Tumor Aggressiveness in Patients With Papillary Thyroid Cancers.

    PubMed

    Lee, Jandee; Jeong, Seonhyang; Lee, Cho Rok; Ku, Cheol Ryong; Kang, Sang-Wook; Jeong, Jong Ju; Nam, Kee-Hyun; Shin, Dong Yeob; Chung, Woong Youn; Lee, Eun Jig; Jo, Young Suk

    2015-06-01

    A significant proportion of patients with papillary thyroid cancer (PTC) present with extrathyroidal extension (ETE) and lymph node metastasis (LNM). However, the molecular mechanism of tumor invasiveness in PTC remains to be elucidated. The aim of this study is to understand the role of Hedgehog (Hh) signaling in tumor aggressiveness in patients with PTC. Subjects were patients who underwent thyroidectomy from 2012 to 2013 in a single institution. Frozen or paraffin-embedded tumor tissues with contralateral-matched normal thyroid tissues were collected. Hh signaling activity was analyzed by quantitative RT-PCR (qRT-PCR) and immunohistochemical (IHC) staining. Datasets from Gene Expression Omnibus (GEO) (National Center for Biotechnology Information) were subjected to Gene Set Enrichment Analysis (GSEA). BRAFT1799A and telomerase reverse transcriptase promoter mutation C228T were analyzed by direct sequencing. Among 137 patients with PTC, glioma-associated oncogene homolog 1 (GLI1) group III (patients in whom the ratio of GLI1 messenger ribonucleic acid (mRNA) level in tumor tissue to GLI1 mRNA level in matched normal tissue was in the upper third of the subject population) had elevated risk for ETE (odds ratio [OR] 4.381, 95% confidence interval [CI] 1.414-13.569, P = 0.01) and LNM (OR 5.627, 95% CI 1.674-18.913, P = 0.005). Glioma-associated oncogene homolog 2 (GLI2) group III also had elevated risk for ETE (OR 4.152, 95% CI 1.292-13.342, P = 0.017) and LNM (OR 3.924, 95% CI 1.097-14.042, P = 0.036). GSEA suggested that higher GLI1 expression is associated with expression of the KEGG gene set related to axon guidance (P = 0.031, false discovery rate < 0.05), as verified by qRT-PCR and IHC staining in our subjects.GLI1 and GLI2 expressions were clearly related to aggressive clinicopathological features and aberrant activation of GLI1 involved in the axon guidance pathway. These results may contribute to development of new prognostic markers

  1. GLI1 Transcription Factor Affects Tumor Aggressiveness in Patients With Papillary Thyroid Cancers

    PubMed Central

    Lee, Jandee; Jeong, Seonhyang; Lee, Cho Rok; Ku, Cheol Ryong; Kang, Sang-Wook; Jeong, Jong Ju; Nam, Kee-Hyun; Shin, Dong Yeob; Chung, Woong Youn; Lee, Eun Jig; Jo, Young Suk

    2015-01-01

    Abstract A significant proportion of patients with papillary thyroid cancer (PTC) present with extrathyroidal extension (ETE) and lymph node metastasis (LNM). However, the molecular mechanism of tumor invasiveness in PTC remains to be elucidated. The aim of this study is to understand the role of Hedgehog (Hh) signaling in tumor aggressiveness in patients with PTC. Subjects were patients who underwent thyroidectomy from 2012 to 2013 in a single institution. Frozen or paraffin-embedded tumor tissues with contralateral-matched normal thyroid tissues were collected. Hh signaling activity was analyzed by quantitative RT-PCR (qRT-PCR) and immunohistochemical (IHC) staining. Datasets from Gene Expression Omnibus (GEO) (National Center for Biotechnology Information) were subjected to Gene Set Enrichment Analysis (GSEA). BRAFT1799A and telomerase reverse transcriptase promoter mutation C228T were analyzed by direct sequencing. Among 137 patients with PTC, glioma-associated oncogene homolog 1 (GLI1) group III (patients in whom the ratio of GLI1 messenger ribonucleic acid (mRNA) level in tumor tissue to GLI1 mRNA level in matched normal tissue was in the upper third of the subject population) had elevated risk for ETE (odds ratio [OR] 4.381, 95% confidence interval [CI] 1.414–13.569, P = 0.01) and LNM (OR 5.627, 95% CI 1.674–18.913, P = 0.005). Glioma-associated oncogene homolog 2 (GLI2) group III also had elevated risk for ETE (OR 4.152, 95% CI 1.292–13.342, P = 0.017) and LNM (OR 3.924, 95% CI 1.097–14.042, P = 0.036). GSEA suggested that higher GLI1 expression is associated with expression of the KEGG gene set related to axon guidance (P = 0.031, false discovery rate < 0.05), as verified by qRT-PCR and IHC staining in our subjects. GLI1 and GLI2 expressions were clearly related to aggressive clinicopathological features and aberrant activation of GLI1 involved in the axon guidance pathway. These results may contribute to development of new

  2. GLI1 Transcription Factor Affects Tumor Aggressiveness in Patients With Papillary Thyroid Cancers.

    PubMed

    Lee, Jandee; Jeong, Seonhyang; Lee, Cho Rok; Ku, Cheol Ryong; Kang, Sang-Wook; Jeong, Jong Ju; Nam, Kee-Hyun; Shin, Dong Yeob; Chung, Woong Youn; Lee, Eun Jig; Jo, Young Suk

    2015-06-01

    A significant proportion of patients with papillary thyroid cancer (PTC) present with extrathyroidal extension (ETE) and lymph node metastasis (LNM). However, the molecular mechanism of tumor invasiveness in PTC remains to be elucidated. The aim of this study is to understand the role of Hedgehog (Hh) signaling in tumor aggressiveness in patients with PTC. Subjects were patients who underwent thyroidectomy from 2012 to 2013 in a single institution. Frozen or paraffin-embedded tumor tissues with contralateral-matched normal thyroid tissues were collected. Hh signaling activity was analyzed by quantitative RT-PCR (qRT-PCR) and immunohistochemical (IHC) staining. Datasets from Gene Expression Omnibus (GEO) (National Center for Biotechnology Information) were subjected to Gene Set Enrichment Analysis (GSEA). BRAFT1799A and telomerase reverse transcriptase promoter mutation C228T were analyzed by direct sequencing. Among 137 patients with PTC, glioma-associated oncogene homolog 1 (GLI1) group III (patients in whom the ratio of GLI1 messenger ribonucleic acid (mRNA) level in tumor tissue to GLI1 mRNA level in matched normal tissue was in the upper third of the subject population) had elevated risk for ETE (odds ratio [OR] 4.381, 95% confidence interval [CI] 1.414-13.569, P = 0.01) and LNM (OR 5.627, 95% CI 1.674-18.913, P = 0.005). Glioma-associated oncogene homolog 2 (GLI2) group III also had elevated risk for ETE (OR 4.152, 95% CI 1.292-13.342, P = 0.017) and LNM (OR 3.924, 95% CI 1.097-14.042, P = 0.036). GSEA suggested that higher GLI1 expression is associated with expression of the KEGG gene set related to axon guidance (P = 0.031, false discovery rate < 0.05), as verified by qRT-PCR and IHC staining in our subjects.GLI1 and GLI2 expressions were clearly related to aggressive clinicopathological features and aberrant activation of GLI1 involved in the axon guidance pathway. These results may contribute to development of new prognostic markers

  3. Reciprocal changes in parathyroid hormone and thyroid function after radioiodine treatment of hyperthyroidism

    SciTech Connect

    Ross, D.S.; Nussbaum, S.R.

    1989-06-01

    Hyperthyroidism is associated with negative calcium balance, normal to increased serum calcium concentrations, and decreased cortical bone mass. There is no agreement concerning serum PTH levels in such patients. In this study, we measured serum PTH concentrations using a newly developed sensitive 2-site immunoradiometric assay in 17 hyperthyroid patients before and after radioiodine therapy. The mean serum PTH and calcium concentrations were 28 +/- 15 (+/- SD) ng/L (normal range, 12-65 ng/L) and 2.4 +/- 0.5 mmol/L (normal range, 2.1-2.6 mmol/L) before therapy. After therapy serum PTH concentrations increased in 16 of the 17 patients. The increase in serum PTH was greater in the 9 patients who became hypothyroid rapidly (29 +/- 15 to 75 +/- 29 ng/L) compared with that in the 8 patients who became euthyroid gradually (26 +/- 16 to 45 +/- 24 ng/L). Serum PTH rose along with TSH as the patients became hypothyroid after radioiodine, and both serum PTH and TSH fell when L-T4 therapy was given. The reciprocal changes in serum PTH concentrations and thyroid function over time suggest a strong association of bone mineral metabolism and thyroid status.

  4. Comparison of the Effects of Iodine and Iodide on Thyroid Function in Humans

    NASA Technical Reports Server (NTRS)

    Robison, Linda M.; Bull, Richard J.; Sylvester, Paul W.; Birkenfeld, Paul; Lang, Jerome

    1995-01-01

    The present experiment in humans failed to confirm the differential effect of I(sub 2) on maintenance of serum T(sub 4) concentrations relative to the effects of I(-) that was observed in prior experiments in rats. The reaction of I(sub 2) with metabolites of thyroid hormones in the intestine that appears responsible for this effect in rats probably also exists at some level in humans. The present results suggest that the concentrations of such metabolites in the human intestinal tract are too small to significantly affect circulating concentration of T(sub 4). However, based on the elevations in TSH, there should be some concern over the potential impacts of chronic consumption of iodine in drinking water.

  5. Thyroid-Stimulating Hormone Within Normal Range Does Not Affect Bone Turnover in Euthyroid Postmenopausal Women with Osteoporotic Fracture - A Preliminary Report

    PubMed Central

    Nowacki, Wieslaw; Sypniewska, Grazyna

    2011-01-01

    Background Pathogenic role of TSH suppression in the damaged bone tissue, in contrast to increased concentrations of thyroid hormones is still unknown. The aim of study was to evaluate the relationship between serum TSH and biochemical bone turnover markers in postmenopausal women with normal thyroid function and to answer whether the differences in TSH concentration within reference range may affect bone metabolism. Material and Methods 34 women (60-93 years old) admitted to the hospital after osteoporotic fracture participated in the study. Serum propeptide of type 1 procollagen (P1NP) as a bone formation marker and crosslinked C-terminal telopeptides (CTX-I), as a bone resorption marker and TSH were assayed. Results Median P1NP (p=0,05) was significantly higher in the 1st tertile of TSH values (0,35-1,88 mlU/mL). In the 3rd tertile of TSH concentrations (3,42-4,94 mlU/mL), the highest CTX-I value was found that exceed the reference range for age. No differences were found in bone markers between a group of euthyroid and a group of subjects with TSH<0,35 mlU/mL. No relationship was observed between TSH and bone formation and resorption markers in the whole group of euthyroid postmenopausal women, however bone formation was found to be in the lower reference range for age in the euthyroid subjects as well as in these with decreased TSH. Weight and BMI correlated negatively with CTX (r=-0,68 p<0,03) in fractured women in the 1st tertile of TSH. Conclusion We found no consistent evidence that TSH concentrations within reference range was associated with changes in bone turnover markers.

  6. Paracrine Interactions of Thyroid Hormones and Thyroid Stimulation Hormone in the Female Reproductive Tract have an Impact on Female Fertility

    PubMed Central

    Stavreus Evers, Anneli

    2012-01-01

    Thyroid disease often causes menstrual disturbances and infertility problems. Thyroid hormone (TH) acts through its receptors, transcription factors present in most cell types in the body. Thyroid stimulating hormone (TSH) stimulates TH synthesis in the thyroid gland, but seems to have other functions as well in the female reproductive tract. The receptors of both TH and TSH increase in the receptive endometrium, suggesting that they are important for implantation, possible by influencing inflammatory mediators such as leukemia inhibitory factor. The roles of these receptors in the ovary need further studies. However, it is likely that the thyroid system is important for both follicular and embryo development. The association between thyroid disease and infertility indicate that TH and TSH affect the endometrium and ovary on the paracrine level. PMID:22649421

  7. Functional analysis of T and B cells from blood and thyroid tissue in Hashimoto's disease.

    PubMed Central

    McLachlan, S M; Proud, G; Pegg, C A; Clark, F; Rees Smith, B

    1985-01-01

    B lymphocytes from Hashimoto blood and thyroid tissue have been cultured with autologous T cells from thyroid/blood to assess their ability to synthesise IgG and thyroid autoantibody. Thyroid B cells were able to synthesize microsomal antibody spontaneously in the absence of T cells or pokeweed mitogen (PWM) and this synthesis was increased in the presence of thyroid T cells without PWM or with blood T cells with PWM. In contrast, blood B cells did not secrete thyroid autoantibody spontaneously but could be induced to do so by thyroid T cells spontaneously or by blood T cells with PWM. Despite these differences, lymphocytes from blood and thyroid tissue secreted microsomal or thyroglobulin antibodies in culture which were similar in terms of the IgG subclass distribution. It would appear, therefore, that although the state of activation of B and T cells is different in blood and thyroid tissue, the precursors of thyroid autoantibody secreting cells are the same. PMID:3872751

  8. Morphological and functional deterioration of the rat thyroid following chronic exposure to low-dose PCB118.

    PubMed

    Tang, Jin-Mei; Li, Wen; Xie, Yu-Chun; Guo, Hong-Wei; Cheng, Pei; Chen, Huan-Huan; Zheng, Xu-Qin; Jiang, Lin; Cui, Dai; Liu, Yun; Ding, Guo-Xian; Duan, Yu

    2013-11-01

    Polychlorinated biphenyls (PCBs) are persistent environmental pollutants that can severely disrupt the synthesis and secretion of endocrine hormones. To investigate the effects of 2,3',4,4',5-pentachlorobiphenyl (PCB118) on thyroid structure and function, 40 male Wistar rats were divided into 4 equal treatment groups and administered vehicle or one of three doses of PCB118. The experimental groups received intraperitoneal (i.p.) injection of 10, 100, or 1000μg/kg/day PCB118, 5 days per week for 13 weeks, whereas the control group was injected with corn oil (vehicle). Serum concentrations of free thyroxine (FT4), free triiodothyronine (FT3) and thyroid stimulating hormone (TSH) were measured by radioimmunoassays. Histopathological and ultrastructural changes in the thyroid were observed under light microscopy and transmission electron microscopy (TEM). The mRNA expression levels of the sodium-iodide symporter (NIS) and thyroglobulin (TG) were quantified by real-time PCR. Increasing doses of PCB118 resulted in progressively lower FT3, FT4 and TSH concentrations in serum. Injection of PCB118 at all doses led to histopathological deterioration of the thyroid characterized by follicular hyperplasia and expansion, shedding of epithelial cells and fibrinoid necrosis. Follicle cells exhibited swollen or vacuolated endoplasmic reticula, as revealed by TEM. Exposure to PCB118 also caused significant decreases in NIS and TG mRNA expression levels. Chronic exposure to low-dose PCB118 and other PCB congeners may be a significant risk factor for thyroid diseases. PMID:23557935

  9. 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...

  10. 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

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

    PubMed

    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

  12. THE EFFECTS OF DE-71, A COMMERCIAL POLYBROMINATED DIPHENYL EITHER MIXTURE, ON FEMALE PUBERTAL DEVELOPMENT AND THYROID FUNCTION

    EPA Science Inventory

    THE EFFECTS OF DE-71, A COMMERICAL POLYBROMINATED DIPHENYL ETHER MIXTURE, ON FEMALE PUBERTAL DEVELOPMENT AND THYROID FUNCTION. S.C. Laws1, J. M. Ferrell1, J. M Hedge2, K. M. Crofton2, R.L. Cooper1, and T.E. Stoker1. 1Reprod. Tox. Div., 2Neurotox. Div., NHEERL, ORD, USEPA, R...

  13. Cigarette smoking and the thyroid.

    PubMed

    Bertelsen, J B; Hegedüs, L

    1994-01-01

    Relevant English language articles published from 1970 through 1993 regarding the possible influence of cigarette smoking on the thyroid were identified through a MEDLINE search and manual searches of identified articles. Thiocyanate in tobacco smoke influences the thyroid by a competitive inhibition of iodine uptake and organification in the gland. Also the stimulation of the sympathetic nervous system by cigarette smoke and benzpyrene, another constituent of tobacco, is thought to influence thyroid gland function. The thyroid hormones and TSH receptor autoantibodies are not affected by smoking, but serum TSH levels have been found to be slightly reduced. Smokers have a higher frequency of goiter and increased serum thyroglobulin levels, especially in iodine-deficient areas. Graves' ophthalmopathy is strongly associated with cigarette smoking; the more severe the eye disease the stronger the association. Graves' disease without ophthalmopathy is also associated with smoking, though this association is weaker. Thiocyanate level in cord blood equilibrates completely with the level in the mother, and a reverse correlation has been demonstrated between birth weight and thiocyanate level in cord blood. Cigarette smoking induces similar changes in thyroid function in the adult and the fetus. No separate study has elucidated the effects of cessation of smoking, but there seems to be longstanding effects induced by smoking, some probably irreversible.

  14. Postpartum thyroiditis.

    PubMed

    Argatska, Antoaneta B; Nonchev, Boyan I

    2014-01-01

    Postpartum thyroiditis (PPT) is a syndrome of transient or permanent thyroid dysfunction occurring in the first year after delivery or abortion. It is the most common thyroid disease in the postpartum period with incidence between 5 and 9%. In essence, it is an autoimmune inflammation of the thyroid, caused by changes in humoral and cell-mediated immune response. It has a characteristic biphasic course with an episode of transient thyrotoxicosis followed by transient or permanent hypothyroidism. Of all predisposing factors positive titers of thyroid peroxidase antibodies have the greatest importance. In some of the affected patients the disease course is marked by expressed hormonal disorders causing significant subjective symptoms. This underlines the need for early identification of risk groups aimed at prophylaxis and adequate treatment of thyroid dysfunction in the postpartum period. The frequency of PPT varies between analyses and studies on risk factors do not establish reliable predictive models for progression of the disease. This is due to the different methodology of research and the involvement of a number of genetic and non-genetic factors in different geographic regions. That is why implementation of mass screening programs is now controversial. The discrepancy in the opinions of researchers makes it necessary to have studies of the problem in performed in every clinical center in which the possible risk specific to the region and the population covered might be defined prognostically. The results of these studies can be used to introduce targeted and cost-effective screening for early detection of risk patients and prevention of morbidity and complications of PPT. PMID:25434070

  15. Postpartum thyroiditis.

    PubMed

    Argatska, Antoaneta B; Nonchev, Boyan I

    2014-01-01

    Postpartum thyroiditis (PPT) is a syndrome of transient or permanent thyroid dysfunction occurring in the first year after delivery or abortion. It is the most common thyroid disease in the postpartum period with incidence between 5 and 9%. In essence, it is an autoimmune inflammation of the thyroid, caused by changes in humoral and cell-mediated immune response. It has a characteristic biphasic course with an episode of transient thyrotoxicosis followed by transient or permanent hypothyroidism. Of all predisposing factors positive titers of thyroid peroxidase antibodies have the greatest importance. In some of the affected patients the disease course is marked by expressed hormonal disorders causing significant subjective symptoms. This underlines the need for early identification of risk groups aimed at prophylaxis and adequate treatment of thyroid dysfunction in the postpartum period. The frequency of PPT varies between analyses and studies on risk factors do not establish reliable predictive models for progression of the disease. This is due to the different methodology of research and the involvement of a number of genetic and non-genetic factors in different geographic regions. That is why implementation of mass screening programs is now controversial. The discrepancy in the opinions of researchers makes it necessary to have studies of the problem in performed in every clinical center in which the possible risk specific to the region and the population covered might be defined prognostically. The results of these studies can be used to introduce targeted and cost-effective screening for early detection of risk patients and prevention of morbidity and complications of PPT. PMID:25507668

  16. 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. PMID:1726925

  17. Defective oxidative phosphorylation in thyroid oncocytic carcinoma is associated with pathogenic mitochondrial DNA mutations affecting complexes I and III.

    PubMed

    Bonora, Elena; Porcelli, Anna Maria; Gasparre, Giuseppe; Biondi, Annalisa; Ghelli, Anna; Carelli, Valerio; Baracca, Alessandra; Tallini, Giovanni; Martinuzzi, Andrea; Lenaz, Giorgio; Rugolo, Michela; Romeo, Giovanni

    2006-06-15

    Oncocytic tumors are characterized by cells with an aberrant accumulation of mitochondria. To assess mitochondrial function in neoplastic oncocytic cells, we studied the thyroid oncocytic cell line XTC.UC1 and compared it with other thyroid non-oncocytic cell lines. Only XTC.UC1 cells were unable to survive in galactose, a condition forcing cells to rely solely on mitochondria for energy production. The rate of respiration and mitochondrial ATP synthesis driven by complex I substrates was severely reduced in XTC.UC1 cells. Furthermore, the enzymatic activity of complexes I and III was dramatically decreased in these cells compared with controls, in conjunction with a strongly enhanced production of reactive oxygen species. Osteosarcoma-derived transmitochondrial cell hybrids (cybrids) carrying XTC.UC1 mitochondrial DNA (mtDNA) were generated to discriminate whether the energetic failure depended on mitochondrial or nuclear DNA mutations. In galactose medium, XTC.UC1 cybrid clones showed reduced viability and ATP content, similarly to the parental XTC.UC1, clearly pointing to the existence of mtDNA alterations. Sequencing of XTC.UC1 mtDNA identified a frameshift mutation in ND1 and a nonconservative substitution in cytochrome b, two mutations with a clear pathogenic potential. In conclusion, this is the first demonstration that mitochondrial dysfunction of XTC.UC1 is due to a combined complex I/III defect associated with mtDNA mutations, as proven by the transfer of the defective energetic phenotype with the mitochondrial genome into the cybrids.

  18. Increased thyroxine turnover and thyroidal function after stimulation of hepatocellular binding of thyroxine by phenobarbital.

    PubMed

    Oppenheimer, J H; Bernstein, G; Surks, M I

    1968-06-01

    Administration of phenobarbital to rats in a dosage schedule previously demonstrated to increase hepatocellular binding of thyroxine results in increased hormonal turnover, due both to increased deiodination and to fecal disposition of thyroxine iodine. The rate of biliary excretion of thyroxine iodine is roughly proportional to the hepatic content of exchangeable thyroxine. The enhanced peripheral disposition of thyroxine appears to lead to increased thyroidal function, as measured by isotopic iodine studies, and the maintenance of a normal nonradioactive serum PBI. On the other hand, thyroidectomized animals maintained on a constant replacement dose of L-thyroxine and treated with phenobarbital exhibit a marked fall in serum PBI. These findings suggest that increased thyroxine flux in phenobarbital-treated animals is secondary to primary stimulation of hepatocellular binding. Exchangeable intracellular thyroxine may thus be an important determinant of hormone turnover and, possibly, of hormonal action.

  19. Pharmacological Activation of Thyroid Hormone Receptors Elicits a Functional Conversion of White to Brown Fat.

    PubMed

    Lin, Jean Z; Martagón, Alexandro J; Cimini, Stephanie L; Gonzalez, Daniel D; Tinkey, David W; Biter, Amadeo; Baxter, John D; Webb, Paul; Gustafsson, Jan-Åke; Hartig, Sean M; Phillips, Kevin J

    2015-11-24

    The functional conversion of white adipose tissue (WAT) into a tissue with brown adipose tissue (BAT)-like activity, often referred to as "browning," represents an intriguing strategy for combating obesity and metabolic disease. We demonstrate that thyroid hormone receptor (TR) activation by a synthetic agonist markedly induces a program of adaptive thermogenesis in subcutaneous WAT that coincides with a restoration of cold tolerance to cold-intolerant mice. Distinct from most other browning agents, pharmacological TR activation dissociates the browning of WAT from activation of classical BAT. TR agonism also induces the browning of white adipocytes in vitro, indicating that TR-mediated browning is cell autonomous. These data establish TR agonists as a class of browning agents, implicate the TRs in the browning of WAT, and suggest a profound pharmacological potential of this action.

  20. Thyroid function testing in eastern Nepal and the impact of CME on subsequent requests.

    PubMed

    Baral, N; Koner, B C; Lamsal, M; Niraula, I; Dhungel, S

    2001-07-01

    This study reveals 1 year's experience of the introduction of thyroid function tests (TFT) in B P Koirala Institute of Health Sciences (BPKIHS), a Medical University situated in eastern Nepal. These were performed on theadvice of doctors working in this region. The rational TFT advice by the medical practitioners was evaluated according to how closely the advice was in line with the algorithms recommended in the textbooks. Only about 14% of the TFT advice followed some rational strategy. A retrospective analysis showed that rational TFT advice could have reduced the cost of a TFT investigation to 43.11% without altering the patient management and disease outcome. Continuing medical education (CME) lectures arranged for a limited number of doctors were found to improve the quality of the subsequentTFT advising pattern. This emphasizes the importance of CME while introducing a costly laboratory test panel (e.g.TFT, lipid profile) needing a strategic approach. PMID:11444339

  1. [Treatments with synthetic antithyroid drugs during pregnancy. Evaluation of the neonatal thyroid function. 25 cases].

    PubMed

    Bricaire, H; Viron, B; Czernichow, P; Luton, J P

    1983-04-16

    Twenty-four hyperthyroid women were treated with antithyroid drugs during 25 pregnancies. The thyroid function of the 21 children who lived was evaluated by standard clinical and laboratory methods. In 8 of these, T3, T4 and TSH were assayed between birth and the 5th day, with timed samplings during the first hours of life. There was no hypothyroxinaemia at birth, but the T4 peak was delayed; T3 was normal. The TSH peak was abnormal in 3 children, one of whom presented with clinical hypothyroidism. All abnormal findings disappeared spontaneously during the first few days of life, except for one child with congenital Grave's disease who had to be treated. On a 6 months to 6 years follow-up all children had normal growth and psychomotor development. PMID:6189116

  2. Long-term effects of allogeneic bone marrow transplantation (BMT) on pituitary, gonad, thyroid and adrenal function in adults.

    PubMed

    Kauppila, M; Koskinen, P; Irjala, K; Remes, K; Viikari, J

    1998-08-01

    To evaluate the late-effects of allogeneic bone marrow transplantation (BMT) on endocrine function 20 adults (10 females, 10 males) with hematological malignancies were studied after a mean of 3.2 years (range 1.0-10.0) following BMT. The mean age of patients at the time of BMT was 39 years. Dynamic tests of the hypothalamic-pituitary axis included growth hormone releasing hormone (GHRH), gonadotropin releasing hormone (GnRH) and thyrotropin releasing hormone (TRH) stimulations with measurements of serum growth hormone (GH), follicle stimulating hormone (FSH), luteinizing hormone (LH), thyrotropin (TSH) and prolactin (PRL) responses. Adrenal function was assessed with the adrenocorticotropin (ACTH) test. Five patients (25%) had a subnormal GH response to GHRH stimulation, but all had a normal serum insulin-like growth factor I (IGF-I) value. There was an inverse nonlinear relationship between the body mass index (BMI; kg/m2) and GH response but no relation between the GH response and total body irradiation (TBI), intrathecal treatment or occurrence of graft-versus-host disease. In females, serum FSH and LH basal levels and responses to GnRH, in spite of oestrogen substitution therapy in 9/10 patients, indicated ovarian failure and early menopause. Most responses to GnRH were delayed. All males had elevated serum basal FSH levels indicating damage in seminiferous tubulus and infertility. Serum basal LH was elevated only in four males but testosterone values were all within normal limits. However, the mean free androgen index (FAI) was in the low normal range, and two subjects had abnormally low FAI. Serum free thyroxine (fT4) levels were normal in all but one, but an exaggerated TSH response to TRH occurred in seven patients (35%). Four of them had received TBI and one total nodal irradiation suggesting radiation-induced damage to the thyroid gland. In 19 of the 20 patients, adrenal function judged with ACTH test was normal. We conclude that functional impairments

  3. Hypothalamic-pituitary-thyroid axis hormones stimulate mitochondrial function and biogenesis in human hair follicles.

    PubMed

    Vidali, Silvia; Knuever, Jana; Lerchner, Johannes; Giesen, Melanie; Bíró, Tamás; Klinger, Matthias; Kofler, Barbara; Funk, Wolfgang; Poeggeler, Burkhard; Paus, Ralf

    2014-01-01

    Thyroid hormones regulate mitochondrial function. As other hypothalamic-pituitary-thyroid (HPT) axis hormones, i.e., thyrotropin-releasing hormone (TRH) and thyrotropin (TSH), are expressed in human hair follicles (HFs) and regulate mitochondrial function in human epidermis, we investigated in organ-cultured human scalp HFs whether TRH (30 nM), TSH (10 mU ml(-1)), thyroxine (T4) (100 nM), and triiodothyronine (T3) (100 pM) alter intrafollicular mitochondrial energy metabolism. All HPT-axis members increased gene and protein expression of mitochondrial-encoded subunit 1 of cytochrome c oxidase (MTCO1), a subunit of respiratory chain complex IV, mitochondrial transcription factor A (TFAM), and Porin. All hormones also stimulated intrafollicular complex I/IV activity and mitochondrial biogenesis. The TSH effects on MTCO1, TFAM, and porin could be abolished by K1-70, a TSH-receptor antagonist, suggesting a TSH receptor-mediated action. Notably, as measured by calorimetry, T3 and TSH increased follicular heat production, whereas T3/T4 and TRH stimulated ATP production in cultured HF keratinocytes. HPT-axis hormones did not increase reactive oxygen species (ROS) production. Rather, T3 and T4 reduced ROS formation, and all tested HPT-axis hormones increased the transcription of ROS scavengers (catalase, superoxide dismutase 2) in HF keratinocytes. Thus, mitochondrial biology, energy metabolism, and redox state of human HFs are subject to profound (neuro-)endocrine regulation by HPT-axis hormones. The neuroendocrine control of mitochondrial biology in a complex human mini-organ revealed here may be therapeutically exploitable. PMID:23949722

  4. Evaluation of calcium and lead interaction, in addition to their impact on thyroid functions in hyper and hypothyroid patients.

    PubMed

    Memon, Nusrat Shahab; Kazi, Tasneem Gul; Afridi, Hassan Imran; Baig, Jameel Ahmed; Arain, Sadaf Sadia; Sahito, Oan Muhammad; Baloch, Shahnawaz; Waris, Muhammad

    2016-01-01

    There is compelling evidence in support of interaction between calcium (Ca) and lead (Pb) in thyroid disorders. The aim of present study was to compare the level of Ca and Pb with thyroid hormones such as thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxin (FT4) in serum samples of hyperthyroid (HPRT) and hypothyroid (HPOT) patients of both genders. For comparative purpose, age-matched (25-50 years) subjects having no thyroid disorders were selected as referents/controls. The serum samples were acid-digested prior to analysis by atomic absorption spectrometry. The validity and accuracy of the methodology were checked by certified reference materials. The resulted data indicates that the mean values of Ca in serum samples of HPRT patients were significantly higher than those of referent subjects (p < 0.01), while reverse pattern was observed in the case of HPOT patients. The level of Pb was higher in the serum samples of both types of thyroid patients, but difference was significant in case of HPOT patients as compare to referent subjects (p < 0.01). A negative correlation was observed between serum Ca levels and TSH of HPRT patients (-r = 0.37-0.39, p < 0.01), while FT3 and FT4 have positive correlation (r = 0.49-0.52 and r = 0.46-0.47), p values <0.01. The Pb in serum had positive correlation with TSH (r = 0.48-0.51, p < 0.005), while negative correlation was observed for FT3 and FT4 (-r = 0.55-0.56, 0.5-0.54, p < 0.05) in HPRT patients. On the other hand, a reverse pattern was observed, for correlation of Ca and Pb with thyroid functions in HPOT patients. PMID:26347420

  5. Carbaryl exposure and recovery modify the interrenal and thyroidal activities and the mitochondria-rich cell function in the climbing perch Anabas testudineus Bloch.

    PubMed

    Peter, Valsa S; Babitha, G S; Bonga, S E Wendelaar; Peter, M C Subhash

    2013-01-15

    We examined the effects of carbaryl (1-naphthyl methylcarbamate; sevin), a carbamate pesticide, on interrenal and thyroid activities and mitochondrial rich (MR) cell function in climbing perch to understand the physiological basis of toxicity acclimation in this fish to the chemical stressor. Carbaryl exposure (5-20 mg L(-1)) for 48 h increased cortisol and glucose, but decreased the T(3) level without affecting T(4) concentration in the plasma. These responses of the carbaryl-exposed fish were nullified and a rise in plasma T(4) occurred in these fish when they were kept for 96 h recovery in clean water. A tight plasma mineral control was indicated in the carbaryl-exposed fish as reflected by the unchanged plasma Na, K, Ca and inorganic phosphate levels. The ouabain-sensitive Na(+), K(+)-ATPase activity showed an increase in the gills but the intestinal and renal tissues showed little response to carbaryl treatment. However, substantial increases in the intestinal and renal Na(+), K(+)-ATPase activities occurred in the recovery fish. The MR cells in the branchial epithelia showed a strong Na(+), K(+)-ATPase immunoreactivity to carbaryl treatment indicating an activated MR cell function. The numerical MR cell density remained unchanged, but stretching of secondary gill lamellae as part of gill remodeling occurred during carbaryl exposure. The increased surface of these lamellae with abundant MR cells as a result of its migration into the lamellar surface points to marked structural and functional modifications of these cells in the carbaryl-treated fish which is likely to a target for carbaryl action. The rise in plasma T(4) and the restoration of normal branchial epithelia in the recovery fish indicate a thyroidal involvement in the recovery response and survival. Our data thus provide evidence that carbaryl exposure and its recovery evoke interrenal and thyroid disruption in this fish leading to a modified osmotic response including an altered MR cell function.

  6. Thyroid function alters during neoadjuvant chemotherapy in breast cancer patients: results from the NEOZOTAC trial (BOOG 2010-01).

    PubMed

    de Groot, S; Janssen, L G M; Charehbili, A; Dijkgraaf, E M; Smit, V T H B M; Kessels, L W; van Bochove, A; van Laarhoven, H W M; Meershoek-Klein Kranenbarg, E; van Leeuwen-Stok, A E; van de Velde, C J H; Putter, H; Nortier, J W R; van der Hoeven, J J M; Pijl, H; Kroep, J R

    2015-01-01

    This side study investigated the effect of chemotherapy on thyroid function and the extent to which it can predict pathological complete response (pCR) in patients with early breast cancer taking part in NEOZOTAC phase III trial, randomizing between neoadjuvant chemotherapy with or without additional zoledronic acid. Moreover, we examined the impact of thyroid function on toxicity. Serum samples of 38 patients were available for analyses. Free thyroxin (fT4) and thyroid stimulating hormone (TSH) levels were compared between baseline and before the 6th cycle and between subjects with and without pCR. The relation between toxicity and the variation in fT4 and TSH levels during chemotherapy was tested. Samples at baseline and before the 6th cycle were available for 31 and 21 patients, respectively. The mean baseline fT4 level was 16.0 pmol/L and TSH level 1.11 mU/L, and these did not differ between both arms at each time point. During six cycles of chemotherapy, fT4 levels decreased (p = 0.0001), and TSH levels increased significantly (p = 0.019). Interestingly, the decrease of fT4 was significantly greater in patients without nausea, vomiting, or neuropathy, than in patients with those side effects (p = 0.037, p = 0.043, and p = 0.050, respectively). Baseline TSH levels tended to be higher in patients with pCR (p = 0.035 univariate analysis and p = 0.074 multivariate analysis). Chemotherapy blunts thyroid function, which was associated with less side effects. These data urge further evaluation of the effects of thyroid function on toxicity and outcome of breast cancer therapy.

  7. 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

  8. Effects of maternal nicotine exposure on thyroid hormone metabolism and function in adult rat progeny.

    PubMed

    Lisboa, P C; de Oliveira, E; Manhães, A C; Santos-Silva, A P; Pinheiro, C R; Younes-Rapozo, V; Faustino, L C; Ortiga-Carvalho, T M; Moura, E G

    2015-03-01

    Postnatal nicotine exposure leads to obesity and hypothyroidism in adulthood. We studied the effects of maternal nicotine exposure during lactation on thyroid hormone (TH) metabolism and function in adult offspring. Lactating rats received implants of osmotic minipumps releasing nicotine (NIC, 6 mg/kg per day s.c.) or saline (control) from postnatal days 2 to 16. Offspring were killed at 180 days. We measured types 1 and 2 deiodinase activity and mRNA, mitochondrial α-glycerol-3-phosphate dehydrogenase (mGPD) activity, TH receptor (TR), uncoupling protein 1 (UCP1), hypothalamic TRH, pituitary TSH, and in vitro TRH-stimulated TSH secretion. Expression of deiodinase mRNAs followed the same profile as that of the enzymatic activity. NIC exposure caused lower 5'-D1 and mGPD activities; lower TRβ1 content in liver as well as lower 5'-D1 activity in muscle; and higher 5'-D2 activity in brown adipose tissue (BAT), heart, and testis, which are in accordance with hypothyroidism. Although deiodinase activities were not changed in the hypothalamus, pituitary, and thyroid of NIC offspring, UCP1 expression was lower in BAT. Levels of both TRH and TSH were lower in offspring exposed to NIC, which presented higher basal in vitro TSH secretion, which was not increased in response to TRH. Thus, the hypothyroidism in NIC offspring at adulthood was caused, in part, by in vivo TRH-TSH suppression and lower sensitivity to TRH. Despite the hypothyroid status of peripheral tissues, these animals seem to develop an adaptive mechanism to preserve thyroxine to triiodothyronine conversion in central tissues. PMID:25653393

  9. Thyroid Function and Perchlorate in Drinking Water: An Evaluation among California Newborns, 1998

    PubMed Central

    Buffler, Patricia A.; Kelsh, Michael A.; Lau, Edmund C.; Edinboro, Charlotte H.; Barnard, Julie C.; Rutherford, George W.; Daaboul, Jorge J.; Palmer, Lynn; Lorey, Fred W.

    2006-01-01

    Perchlorate (ClO4−) has been detected in groundwater sources in numerous communities in California and other parts of the United States, raising concerns about potential impacts on health. For California communities where ClO4− was tested in 1997 and 1998, we evaluated the prevalence of primary congenital hypothyroidism (PCH) and high thyroid-stimulating hormone (TSH) levels among the 342,257 California newborns screened in 1998. We compared thyroid function results among newborns from 24 communities with average ClO4− concentrations in drinking water > 5 μg/L (n = 50,326) to newborns from 287 communities with average concentrations ≤5 μg/L (n = 291,931). ClO4− concentrations obtained from the California Drinking Water Program provided source-specific data for estimating weighted average concentrations in community water. Fifteen cases of PCH from communities with average concentration > 5 μg/L were observed, with 20.4 expected [adjusted prevalence odds ratio (POR) = 0.71; 95% confidence interval (CI), 0.40–1.19]. Although only 36% of all California newborns were screened before 24 hr of age in 1998, nearly 80% of newborns with high TSH were screened before 24 hr of age. Because of the physiologic postnatal surge of TSH, the results for newborns screened before 24 hr were uninformative for assessing an environmental impact. For newborns screened ≥24 hr, the adjusted POR for high TSH was 0.73 (95% CI, 0.40–1.23). All adjusted odds ratios (ORs) were controlled for sex, ethnicity, birth weight, and multiple birth status. Using an assessment of ClO4− in drinking water based on available data, we did not observe an association between estimated average ClO4− concentrations > 5 μg/L in drinking water supplies and the prevalence of clinically diagnosed PCH or high TSH concentrations. PMID:16675440

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

    PubMed Central

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

    2015-01-01

    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. PMID:26431489

  11. 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. PMID:26431489

  12. Thyroid-gonad relationship in chronic schizophrenia.

    PubMed

    Parshad, O; Uppal, A

    1989-06-01

    The effects of the severity of psychiatric illnesses on thyroid function and their relationship to serum testosterone levels were studied in 38 men of African origin, suffering from chronic schizophrenia. Significantly lower levels of serum T4, T3, FT4I and testosterone in acutely psychotic patients indicated decreased thyroid-gonadal activity. Higher serum T4 and FT4I and lower serum TSH, testosterone and cortisol levels were observed in patients whose illnesses were in remission. Levels of both FT4I and testosterone in clinically stable patients, however, were not significantly different in comparison to controls, suggesting recovery from the illness. No significant differences either in thyroid or gonadal hormones were observed between patients exhibiting depression or elated affects; among disorganized, catatonic, paranoid and undifferentiated types; and among patients treated with different psychotropic drugs. The possible mechanisms involved in such thyroid-gonad relationship are discussed.

  13. Onco-lncRNA HOTAIR and its functional genetic variants in papillary thyroid carcinoma

    PubMed Central

    Zhu, Hui; Lv, Zheng; An, Changming; Shi, Meng; Pan, Wenting; Zhou, Liqing; Yang, Wenjun; Yang, Ming

    2016-01-01

    The role of long noncoding RNA (lncRNA) HOX transcript antisense RNA (HOTAIR) and its functional single nucleotide polymorphisms (SNPs) in papillary thyroid carcinoma (PTC) is still largely unclear. Therefore, we investigated the involvement of lncRNA HOTAIR and its three haplotype-tagging SNPs (htSNPs) in PTC. There was higher expression of HOTAIR in PTC tissues compared to normal tissues. A series of gain-loss assays demonstrated that HOTAIR acts as a PTC oncogene via promoting tumorigenic properties of PTC cells. Additionally, the functional HOTAIR rs920778 genetic variant was a PTC susceptibility SNP. Subjects with the HOTAIR rs920778 TT genotype had an odds ratio (OR) of 1.88, 1.25 and 1.61 (P = 6.0 × 10−6, P = 0.028 and P = 3.2 × 10−5) for developing PTC in Shandong, Jiangsu and Jilin case-control sets compared with subjects with the CC genotype. This statistically significant associations were only found between the rs920778 genetic polymorphism and PTC risk in females but not in males. The allele-specific regulation on HOTAIR expression by the rs920778 SNP was confirmed both in vitro and in vivo. Our results demonstrate that functional SNPs influencing lncRNA regulation may explain a part of PTC genetic basis. PMID:27549736

  14. [Thyroid disease].

    PubMed

    Ashitaka, Y

    1990-08-01

    The incidence of pregnant women with thyroid dysfunction has been reported to be around 0.1-0.4%. Graves' disease accounts for more than half of these disorders. The main cause of thyroid disease in pregnancy and puerperium is autoimmune dysfunction. Whether there may be goitre or exophthalmus present, clinical signs as inappropriate weight gain, high systolic pressure, palpitation (greater than or equal to 110/min), emotional lability, fatigue, acceleration of suppression of the Achilles' tendon reflex should induce changes in the biochemical thyroid function tests. Parameters for the diagnosis and management for hyperthyroidism are serum levels of free T4 and TSH, while those of T3, reverse T3, and TSH are for hypothyroidism. Serum anti-microsomal antibodies and anti-thyroglobulin antibodies which have no effect on the fetus are also good markers for severity. The transplacental transfer of maternal TSH receptor antibodies consisting of stimulatory and inhibitory immunoglobulins and maternal thyroid-binding inhibiting immunoglobulins play roles in the development of transient neonatal hyper- or hypothyroidism. Fetal control is achieved by optimal maternal management. Untreated hyperthyroidism may be associated with fetal malformations. This risk may be reduced by antithyroid drug treatment of up to 150 mg/day of propylthiouracil which has less chance of placental passage and less secretion into the mother's milk than methyl-mercapto-imidazol. Maternal thyroid function should be kept in the upper limit of normal range, taking into consideration the fetal dysfunction induced by over-administration of the drug which passes through placenta. Children of hypothyroid women taking inadequate replacement therapy manifested lower IQ values compared to the progeny of euthyroid or hypothyroid women taking adequate therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

  15. Blood Lead Concentration and Thyroid Function during Pregnancy: Results from the Yugoslavia Prospective Study of Environmental Lead Exposure

    PubMed Central

    Kahn, Linda G.; Liu, Xinhua; Rajovic, Biljana; Popovac, Dusan; Oberfield, Sharon; Graziano, Joseph H.

    2014-01-01

    Background: Although maternal hypothyroidism increases the risk of adverse neonatal and obstetric outcomes as well as lower IQ in children, the environmental determinants of maternal thyroid dysfunction have yet to be fully explored. Objectives: We aimed to examine associations between mid-pregnancy blood lead (BPb) and concomitant measures of thyroid function among participants in the Yugoslavia Prospective Study of Environmental Lead Exposure. Methods: As part of a population-based prospective study of two towns in Kosovo—one with high levels of environmental lead and one with low—women were recruited during the second trimester of pregnancy, at which time blood samples and questionnaire data were collected. We measured concentrations of BPb, free thyroxine (FT4), thyroid-stimulating hormone (TSH), and thyroid peroxidase antibodies (TPOAb) in archived serum samples. Results: Compared with women from the unexposed town, women from the exposed town had lower mean FT4 (0.91 ± 0.17 vs. 1.03 ± 0.16 ng/dL), higher mean TPOAb (15.45 ± 33.08 vs. 5.12 ± 6.38 IU/mL), and higher mean BPb (20.00 ± 6.99 vs. 5.57 ± 2.01 μg/dL). No differences in TSH levels were found. After adjustment for potential confounders, for each natural log unit increase in BPb, FT4 decreased by 0.074 ng/dL (95% CI: –0.10, –0.046 ng/dL), and the odds ratio for testing positive to TPOAb was 2.41 (95% CI: 1.53, 3.82). We found no association between BPb and TSH. Conclusions: Prolonged lead exposure may contribute to maternal thyroid dysfunction by stimulating autoimmunity to the thyroid gland. Citation: Kahn LG, Liu X, Rajovic B, Popovac D, Oberfield S, Graziano JH, Factor-Litvak P. 2014. Blood lead concentration and thyroid function during pregnancy: results from the Yugoslavia Prospective Study of Environmental Lead Exposure. Environ Health Perspect 122:1134–1140; http://dx.doi.org/10.1289/ehp.1307669 PMID:24866691

  16. Thyroid hormone and retinoid X receptor function and expression during sea lamprey (Petromyzon marinus) metamorphosis.

    PubMed

    Manzon, Lori A; Youson, John H; Holzer, Guillaume; Staiano, Leopoldo; Laudet, Vincent; Manzon, Richard G

    2014-08-01

    Sea lampreys (Petromyzon marinus) are members of the ancient class Agnatha and undergo a metamorphosis that transforms blind, sedentary, filter-feeding larvae into free-swimming, parasitic juveniles. Thyroid hormones (THs) appear to be important for lamprey metamorphosis, however, serum TH concentrations are elevated in the larval phase, decline rapidly during early metamorphosis and remain low until metamorphosis is complete; these TH fluctuations are contrary to those of other metamorphosing vertebrates. Moreover, thyroid hormone synthesis inhibitors (goitrogens) induce precocious metamorphosis and exogenous TH treatments disrupt natural metamorphosis in P. marinus. Given that THs exert their effects by binding to TH nuclear receptors (TRs) that often act as heterodimers with retinoid X receptors (RXRs), we cloned and characterized these receptors from P. marinus and examined their expression during metamorphosis. Two TRs (PmTR1 and PmTR2) and three RXRs (PmRXRs) were isolated from P. marinus cDNA. Phylogenetic analyses group the PmTRs together on a branch prior to the gnathostome TRα/β split. The three RXRs also group together, but our data indicated that these transcripts are most likely either allelic variants of the same gene locus, or the products of a lamprey-specific duplication event. Importantly, these P. marinus receptors more closely resemble vertebrate as opposed to invertebrate chordate receptors. Functional analysis revealed that PmTR1 and PmTR2 can activate transcription of TH-responsive genes when treated with nanomolar concentrations of TH and they have distinct pharmacological profiles reminiscent of vertebrate TRβ and TRα, respectively. Also similar to other metamorphosing vertebrates, expression patterns of the PmTRs during lamprey metamorphosis suggest that PmTR1 has a dynamic, tissue-specific expression pattern that correlates with tissue morphogenesis and biochemical changes and PmTR2 has a more uniform expression pattern. This TR

  17. Timing of Adjuvant Radioactive Iodine Therapy Does Not Affect Overall Survival in Low- and Intermediate-Risk Papillary Thyroid Carcinoma.

    PubMed

    Suman, Paritosh; Wang, Chi-Hsiung; Moo-Young, Tricia A; Prinz, Richard A; Winchester, David J

    2016-09-01

    There is no consensus regarding the timing of adjuvant radioactive iodine therapy (RAI) therapy in low- and intermediate-risk papillary thyroid carcinoma (PTC). We analyzed the impact of adjuvant RAI on overall survival (OS) in low- and intermediate-risk PTC. The National Cancer Data Base was queried from 2004 to 2011 for pN0M0 PTC patients having near/subtotal or total thyroidectomy and adjuvant RAI. Tumors ≤1 cm with negative margins were low risk while 1.1- to 4-cm tumors with negative margins or ≤1 cm with microscopic margins were termed intermediate risk. RAI in ≤3 months and between 3 and 12 months was termed as early and delayed, respectively. Survival analysis was performed after adjusting for patient and tumor-related variables. There were 7,306 low-risk and 16,609 intermediate-risk patients. Seventeen per cent low-risk and 15 per cent intermediate-risk patients had delayed RAI. Kaplan-Meier analysis did not show a difference in OS for early versus delayed RAI administration in low- (10-year OS 94.5% vs 94%, P = 0.627) or intermediate-risk (10-year OS 95.3% vs 95.9%, P = 0.944) patients. In adjusted survival analysis, RAI timing did not affect OS in all patients (hazard ratios = 0.98, 95% confidence interval = 0.71-1.34, P = 0.887). In conclusion, the timing of postthyroidectomy adjuvant RAI therapy does not affect OS in low- or intermediate-risk PTC. PMID:27670568

  18. Thyroid Tests

    MedlinePlus

    ... Organizations (PDF, 269 KB). Alternate Language URL Thyroid Tests Page Content On this page: What is the ... Top ] Why do health care providers perform thyroid tests? Health care providers perform thyroid tests to assess ...

  19. Subacute thyroiditis

    MedlinePlus

    Laboratory tests that may be done include: Thyroid stimulating hormone (TSH) level T4 (thyroid hormone, thyroxine) and T3 level Radioactive iodine uptake Thyroglobulin level Erythrocyte sedimentation rate (ESR) In some cases, a thyroid ...

  20. Silent thyroiditis

    MedlinePlus

    ... gland. The disorder can cause hyperthyroidism, followed by hypothyroidism. The thyroid gland is located in the neck, ... Later symptoms may be of an underactive thyroid ( hypothyroidism ), including fatigue and cold intolerance, until the thyroid ...

  1. Thyroid Surgery

    MedlinePlus

    ... thyroid surgery, requiring treatment with thyroid hormone (see Hypothyroidism brochure ). This is especially true if you had ... Nodules Goiter Graves’ Disease Hashimoto’s Thyroiditis Hyperthyroidism (Overactive) Hypothyroidism (Underactive) Iodine Deficiency Low Iodine Diet Radioactive Iodine ...

  2. Thyroid scan

    MedlinePlus

    ... thyroid; Radioactive iodine uptake and scan test - thyroid; Nuclear scan - thyroid ... the test. Ask your provider or the radiology/nuclear medicine team performing the scan about taking precautions.

  3. Comparison of the Reference Intervals Used for the Evaluation of Maternal Thyroid Function During Pregnancy Using Sequential and Nonsequential Methods

    PubMed Central

    Fan, Jian-Xia; Yang, Shuai; Qian, Wei; Shi, Feng-Tao; Huang, He-Feng

    2016-01-01

    Background: Maternal thyroid dysfunction is common during pregnancy, and physiological changes during pregnancy can lead to the overdiagnosis of hyperthyroidism and misdiagnosis of hypothyroidism with nongestation-specific reference intervals. Our aim was to compare sequential with nonsequential methods for the evaluation of thyroid function in pregnant women. Methods: We tested pregnant women who underwent their trimester prenatal screening at our hospital from February 2011 to September 2012 for serum thyroid stimulating hormone (TSH) and free thyroxine (FT4) using the Abbott and Roche kits. There were 447 and 200 patients enrolled in the nonsequential and sequential groups, respectively. The central 95% range between the 2.5th and the 97.5th percentiles was used as the reference interval for the thyroid function parameter. Results: The nonsequential group exhibited a significantly larger degree of dispersion in the TSH reference interval during the 2nd and 3rd trimesters as measured using both the Abbott and Roche kits (all P < 0.05). The TSH reference intervals were significantly larger in the nonsequential group than in the sequential group during the 3rd trimester as measured with both the Abbott (4.95 vs. 3.77 mU/L, P < 0.001) and Roche kits (6.62 vs. 5.01 mU/L, P = 0.004). The nonsequential group had a significantly larger FT4 reference interval as measured with the Abbott kit during all trimesters (12.64 vs. 5.82 pmol/L; 7.96 vs. 4.77 pmol/L; 8.10 vs. 4.77 pmol/L, respectively, all P < 0.05), whereas a significantly larger FT4 reference interval was only observed during the 2nd trimester with the Roche kit (7.76 vs. 5.52 pmol/L, P = 0.002). Conclusions: It was more reasonable to establish reference intervals for the evaluation of maternal thyroid function using the sequential method during each trimester of pregnancy. Moreover, the exclusion of pregnancy-related complications should be considered in the inclusion criteria for thyroid function tests. PMID

  4. Thyroid-specific enhancer-binding protein (T/EBP): cDNA cloning, functional characterization, and structural identity with thyroid transcription factor TTF-1

    SciTech Connect

    Mizuno, Kimio; Gonzalez, F.J.; Kimura, S. )

    1991-10-01

    A cDNA clone encoding a thyroid-specific enhancer-binding protein (T/EBP) was isolated from a rat thyroid-derived FRTL-5 cell {lambda}gt 11 expression library, using a double-stranded oligonucleotide probe. This oligonucleotide was previously demonstrated to have the strongest binding affinity among three cis-acting DNA elements within the thyroid-specific enhancer region located 5.5 kbp upstream of the human thyroid peroxidase gene transcription start site. Nucleotide and deduced amino acid sequences of the cDNA revealed that T/EBP is identical to the previously reported thyroid-specific transcription factor 1 (TTF-1), which binds to the promoter of the rat thyroglobulin gene and controls its thyroid-specific expression. Expression of the T/EBP cDNA under control of the human cytomegalovirus major immediate-early gene promoter conferred thyroid-specific enhancer activity of as high as 26-fold to nonpermissive human hepatoma HepG2 cells when cotransfected with a vector containing 6.3 kbp of upstream sequence of the human thyroid peroxidase gene connected to a luciferase reporter gene. These results clearly indicate that the binding of T/EBP (TTF-1) to the specific cis-acting enhancer element is largely responsible for thyroid-specific enhancer activity.

  5. 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...

  6. Radioactive iodine treatment of a functional thyroid carcinoma producing hyperthyroidism in a dog

    SciTech Connect

    Peterson, M.E.; Kintzer, P.P.; Hurley, J.R.; Becker, D.V.

    1989-01-01

    Radioactive iodine (/sup 131/I) was used in the treatment of a 12-year-old female dog with hyperthyroidism resulting from a large, unresectable (and metastatic) thyroid carcinoma associated with signs of severe inspiratory stridor and dyspnea. Hyperthyroidism was diagnosed on the basis of clinical signs (polyuria, polydipsia, polyphagia, weight loss, nervousness) and high basal serum thyroxine (T4) concentrations, as well as thyroid radioiodine kinetic studies that showed a high radioiodine uptake into the thyroid (% thyroid uptake) and markedly increased serum concentrations of protein-bound iodine-131 (PB/sup 131/I) after /sup 131/I tracer injection. Thyroid imaging revealed diffuse radionuclide accumulation by the tumor, which involved both thyroid lobes. The dog was treated with three large doses of radioiodine (/sup 131/I), ranging from 60 to 75 mCi, given at intervals of 5 to 7 months. The dog became euthyroid, and the size of the tumor decreased by approximately 25% after each /sup 131/I treatment, improving the severe inspiratory stridor and dyspnea, but both the hyperthyroid state and breathing difficulty recurred within a few months of each treatment. The dog was euthanatized 5 months after the last treatment because of progressive tracheal compression and pulmonary metastasis.

  7. Effects of perfluoroalkyl acids on the function of the thyroid hormone and the aryl hydrocarbon receptor.

    PubMed

    Long, Manhai; Ghisari, Mandana; Bonefeld-Jørgensen, Eva Cecilie

    2013-11-01

    Perfluoroalkyl acids (PFAAs) are perfluorinated compounds that widely exist in the environment and can elicit adverse effects including endocrine disruption in humans and animals. This study investigated the effect of seven PFAAs on the thyroid hormone (TH) system assessing the proliferation of the 3,3',5-triiodo-L-thryonine (T3)-dependent rat pituitary GH3 cells using the T-screen assay and the effect on the aryl hydrocarbon receptor (AhR) transactivation in the AhR-luciferase reporter gene bioassay. A dose-dependent impact on GH3 cells was observed in the range 1×10(-9)-1×10(-4) M: seven PFAAs (perfluorooctane sulfonate (PFOS), perfluorohexane sulfonate (PFHxS), perfluorooctanoic acid, perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluoroundecanoic acid (PFUnA), and perfluorododecanoic acid (PFDoA)) inhibited the GH3 cell growth, and four PFAAs (PFOS, PFHxS, PFNA, and PFUnA) antagonized the T3-induced GH3 cell proliferation. At the highest test concentration, PFHxS showed a further increase of the T3-induced GH3 growth. Among the seven tested PFAAs, only PFDoA and PFDA elicited an activating effect on the AhR. In conclusion, PFAAs possess in vitro endocrine-disrupting potential by interfering with TH and AhR functions, which need to be taken into consideration when assessing the impact on human health. PMID:23539207

  8. Parathyroid gland angiography with indocyanine green fluorescence to predict parathyroid function after thyroid surgery

    PubMed Central

    Vidal Fortuny, J.; Belfontali, V.; Sadowski, S. M.; Karenovics, W.; Guigard, S.

    2016-01-01

    Background Postoperative hypoparathyroidism remains the most common complication following thyroidectomy. The aim of this pilot study was to evaluate the use of intraoperative parathyroid gland angiography in predicting normal parathyroid gland function after thyroid surgery. Methods Angiography with the fluorescent dye indocyanine green (ICG) was performed in patients undergoing total thyroidectomy, to visualize vascularization of identified parathyroid glands. Results Some 36 patients underwent ICG angiography during thyroidectomy. All patients received standard calcium and vitamin D supplementation. At least one well vascularized parathyroid gland was demonstrated by ICG angiography in 30 patients. All 30 patients had parathyroid hormone (PTH) levels in the normal range on postoperative day (POD) 1 and 10, and only one patient exhibited asymptomatic hypocalcaemia on POD 1. Mean(s.d.) PTH and calcium levels in these patients were 3·3(1·4) pmol/l and 2·27(0·10) mmol/l respectively on POD 1, and 4·0(1.6) pmol/l and 2·32(0·08) mmol/l on POD 10. Two of the six patients in whom no well vascularized parathyroid gland could be demonstrated developed transient hypoparathyroidism. None of the 36 patients presented symptomatic hypocalcaemia, and none received treatment for hypoparathyroidism. Conclusion PTH levels on POD 1 were normal in all patients who had at least one well vascularized parathyroid gland demonstrated during surgery by ICG angiography, and none required treatment for hypoparathyroidism. PMID:26864909

  9. Thyroid Echography-induced Thyroid Storm and Exacerbation of Acute Heart Failure.

    PubMed

    Nakabayashi, Keisuke; Nakazawa, Naomi; Suzuki, Toshiaki; Asano, Ryotaro; Saito, Hideki; Nomura, Hidekimi; Isomura, Daichi; Okada, Hisayuki; Sugiura, Ryo; Oka, Toshiaki

    2016-01-01

    Hyperthyroidism and thyroid storm affect cardiac circulation in some conditions. Several factors including trauma can induce thyroid storms. We herein describe the case of a 57-year-old woman who experienced a thyroid storm and exacerbation of acute heart failure on thyroid echography. She initially demonstrated a good clinical course after medical rate control for atrial fibrillation; however, thyroid echography for evaluating hyperthyroidism led to a thyroid storm and she collapsed. A multidisciplinary approach stabilized her thyroid hormone levels and hemodynamics. Thus, the medical staff should be prepared for a deterioration in the patient's condition during thyroid echography in heart failure patients with hyperthyroidism.

  10. Thyroid Echography-induced Thyroid Storm and Exacerbation of Acute Heart Failure.

    PubMed

    Nakabayashi, Keisuke; Nakazawa, Naomi; Suzuki, Toshiaki; Asano, Ryotaro; Saito, Hideki; Nomura, Hidekimi; Isomura, Daichi; Okada, Hisayuki; Sugiura, Ryo; Oka, Toshiaki

    2016-01-01

    Hyperthyroidism and thyroid storm affect cardiac circulation in some conditions. Several factors including trauma can induce thyroid storms. We herein describe the case of a 57-year-old woman who experienced a thyroid storm and exacerbation of acute heart failure on thyroid echography. She initially demonstrated a good clinical course after medical rate control for atrial fibrillation; however, thyroid echography for evaluating hyperthyroidism led to a thyroid storm and she collapsed. A multidisciplinary approach stabilized her thyroid hormone levels and hemodynamics. Thus, the medical staff should be prepared for a deterioration in the patient's condition during thyroid echography in heart failure patients with hyperthyroidism. PMID:27522996

  11. Thyroid imaging studies

    SciTech Connect

    Drew, H.H.; LaFrance, N.D.; Chen, J.J.S.

    1987-06-01

    This is the second in a series of Continuing Education articles related to functional/quantitative imaging techniques. After reading this article, the reader should be able to: 1) discuss the clinical applications of thyroid imaging; 2) understand the relationship of related thyroid tests; and 3) recognize the pitfalls and problems associated with this procedure.

  12. Thyroid and Aging or the Aging Thyroid? An Evidence-Based Analysis of the Literature

    PubMed Central

    2013-01-01

    Thyroid hormone production, metabolism, and action change with aging. The reference ranges for serum thyrotropin and thyroid hormones are derived mainly from younger populations. Thus, the prevalence of subclinical thyroid dysfunction is increased greatly in the elderly. However, it is unclear whether mild thyroid dysfunction in the elderly is associated with adverse outcomes. In this review, we discuss current evidence-based literature on thyroid function in the elderly and whether subclinical thyroid dysfunction in the elderly should be treated. PMID:24106641

  13. Thyroid Cancer

    MedlinePlus

    ... are here Home > Types of Cancer > Thyroid Cancer Thyroid Cancer This is Cancer.Net’s Guide to Thyroid Cancer. Use the menu below to choose the ... social workers, and patient advocates. Cancer.Net Guide Thyroid Cancer Overview Statistics Medical Illustrations Risk Factors Symptoms ...

  14. A Nonradioactive Uptake Assay for Rapid Analysis of Thyroid Hormone Transporter Function.

    PubMed

    Jayarama-Naidu, Roopa; Johannes, Jörg; Meyer, Franziska; Wirth, Eva Katrin; Schomburg, Lutz; Köhrle, Josef; Renko, Kostja

    2015-07-01

    Thyroid hormones (TH) are actively taken up into target cells via TH-transmembrane transporters (THTT). Their activity and expression patterns define a layer of endocrine regulation that is poorly understood. Therefore, THTT are potential targets for interfering agents (endocrine disruptors) as well as for pharmacological interventions. Inactivating mutations have been identified as the underlying cause of heritable diseases (monocarboxylate transporter 8-associated Allan-Herndon-Dudley syndrome) and might also define a class of subclinical TH insensitivity. As a basic tool to solve questions regarding THTT substrate specificity, activation or inactivation by compounds and functional changes from mutations, uptake assays with radiolabeled tracers are standard. Due to the need for radioactive isotopes, this technique is limited to screening of labelled substrates and disadvantageous regarding handling, setup, and regulatory issues. To overcome these hurdles, we developed an uptake assay protocol using nonradioactive ligands. In brief, uptake of nonradioactive iodine-containing substrate molecules was monitored via Sandell-Kolthoff reaction. The novel assay was designed to the common microtiter plate layout. As a prove-of-principle, we measured TH uptake by monocarboxylate transporter 8-transfected MDCK1 cells. Titrations with bromosulphthalein as an example for inhibitor screening setups and a side-by-side comparison with the radioactive method prove this assay to be reliable, sensitive, and convenient. Furthermore, the method was applicable on primary murine astrocytes, which enables high-throughput screening studies on in vitro model systems with physiological transporter regulation. Due to its design, it is applicable for high-throughput screening of modulatory compounds, but it is also a safe, inexpensive and an easily accessible method for functional testing of THTT in basic science. PMID:25910050

  15. Cardiac Function in Newborns with Congenital Hypothyroidism: Association with Thyroid-Stimulating Hormone Levels

    PubMed Central

    Öner, Taliha; Özdemir, Rahmi; Doksöz, Önder; Yozgat, Yılmaz; Karadeniz, Cem; Demirpençe, Savaş; Yılmazer, Murat Muhtar; Büyükinan, Muammer; Meşe, Timur; Tavlı, Vedide

    2015-01-01

    Objective: The aims of this study were to demonstrate ventricular function changes in patients with congenital hypothyroidism and to investigate whether there is an association between any such changes and thyroid-stimulating hormone (TSH) levels using M-mode and Doppler electrocardiography (ECG) and tissue Doppler imaging (TDI). Methods: Twenty-seven patients 5-30 days of age with congenital hypothyroidism who were scheduled to receive L-thyroxine treatment and 20 healthy newborns were included in this study. Twelve-lead ECG and M-mode TDI recordings of the patient and healthy groups were obtained. The patient group was divided into two subgroups according to TSH level (>100 uIU/mL or <100 uIU/mL), which were then compared on all parameters. Results: Decreases were observed in the ejection fraction (EF), shortening fraction (SF), and mitral lateral annulus, mitral septal annulus, and tricuspid lateral annulus systolic velocity (Sa) on TDI, whereas left ventricular end-systolic diameter (LVESd) and corrected QT interval (QTc) dispersion were significantly increased in the patient group compared with the control group. No significant differences between the groups were found in left ventricular end-diastolic diameter (LVEDd) or heart rate. When the two patient subgroups (TSH >100 uIU/mL and <100 uIU/mL) were compared, TDI septal annulus Sa wave length and heart rate were significantly lower in the TSH >100 group. Conclusion: Impairment in left ventricular systolic function and increased risk of arrhythmia were observed in newborn infants with congenital hypothyroidism. TSH level was associated with heart rate and interventricular septum velocity. PMID:26777042

  16. Integument structure and function in juvenile Xenopus laevis with disrupted thyroid balance.

    PubMed

    Carvalho, Edison S M; Fuentes, Juan; Power, Deborah M

    2011-12-01

    The skin is the largest organ in the body and is a barrier between the internal and external environment. The present study evaluates how PTU, a goitrogen, that is used to treat hyperthyroidism affects the structure and electrical properties of the frog (Xenopus laevis) skin. The results are considered in the context of the two-membrane model established in the seminal work of Ussing and collegues in the 1940s and 1950s. In vitro experiments with skin from Xenopus adults revealed that PTU can act directly on skin and causes a significant increase (p<0.05, One-way ANOVA) in short circuit current (Isc) via an amiloride-insensitive mechanism. Juvenile Xenopus exposed to waterborne PTU (5 mg/L) had a significantly bigger and more active thyroid gland (p<0.01, Student's t-test) than control Xenopus. The bioelectric properties of skin taken from Xenopus juveniles treated with PTU in vivo had a lower Isc, (3.05±0.4, n=13) and Rt (288.2±39.5) than skin from control Xenopus (Isc, 4.19±1.14, n=14; Rt, 343.3±43.3). A histological assessment of skin from PTU treated Xenopus juveniles revealed the epidermis was significantly thicker (p<0.01, Student's t-test) and had a greater number of modified exocrine glands (p<0.01, Student's t-test) in the dermis compared to control skin. Modifications in skin structure are presumably the basis for its changed bioelectric properties and the study highlights a site of action for environmental chemicals which has been largely neglected. PMID:21963960

  17. Comparison of the in vitro effects of TCDD, PCB 126 and PCB 153 on thyroid-restricted gene expression and thyroid hormone secretion by the chicken thyroid gland.

    PubMed

    Katarzyńska, Dorota; Hrabia, Anna; Kowalik, Kinga; Sechman, Andrzej

    2015-03-01

    The aim of this study was to compare the in vitro effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 3,3',4,4',5-pentachlorobiphenyl (PCB 126; a coplanar PCB congener) and 2,2'4,4',5,5'-hexachlorobiphenyl (PCB153; non-coplanar PCB) on mRNA expression of thyroid-restricted genes, i.e. sodium iodide symporter (NIS), thyroid peroxidase (TPO) and thyroglobulin (TG), and thyroid hormone secretion from the thyroid gland of the laying chicken. Relative expression levels of NIS, TG and TPO genes and thyroxine (T4) and triiodothyronine (T3) secretion from the thyroidal explants were quantified by the real-time qPCR and RIA methods, respectively. In comparison with the control group, TCDD and PCB 126 significantly increased mRNA expression of TPO and TG genes. TCDD did not affect NIS mRNA levels, but PCB 126 decreased its expression. No effect of PCB 153 on the expression of these genes was observed. TCDD and PCB 126 significantly decreased T4 and T3 secretion. There was no significant effect of PCB 153 on these hormone secretions. In conclusion, the results obtained show that in comparison with non-coplanar PCB 153, TCDD and coplanar PCB 126 can directly affect thyroid hormone synthesis and secretion, and in consequence, they may disrupt the endocrine function of the thyroid gland of the laying chicken.

  18. Thyroid ultrasound

    PubMed Central

    Chaudhary, Vikas; Bano, Shahina

    2013-01-01

    Thyroid ultrasonography has established itself as a popular and useful tool in the evaluation and management of thyroid disorders. Advanced ultrasound techniques in thyroid imaging have not only fascinated the radiologists but also attracted the surgeons and endocrinologists who are using these techniques in their daily clinical and operative practice. This review provides an overview of indications for ultrasound in various thyroid diseases, describes characteristic ultrasound findings in these diseases, and illustrates major diagnostic pitfalls of thyroid ultrasound. PMID:23776892

  19. Longitudinal study on thyroid function in patients with thalassemia major: High incidence of central hypothyroidism by 18 years

    PubMed Central

    Soliman, Ashraf T.; Al Yafei, Fawzia; Al-Naimi, Lolwa; Almarri, Noora; Sabt, Aml; Yassin, Mohamed; De Sanctis, Vincenzo

    2013-01-01

    Introduction: Primary hypothyroidism is one of the most frequent complications observed in-patients suffering from thalassemia. We investigated and reviewed the thyroid function in all thalassemic patients attending the Pediatric Endocrine Clinic of Hamad Medical Center, Doha, Qatar during the last 10 years of follow-up. Patients and Methods: A total of 48 patients with ί-thalassemia major between 5 years and 18 years of age. Thyroid dysfunction was defined as follows: Overt hypothyroidism (low Free thyroxine [FT4] and increased thyroid-stimulating hormone [TSH] levels >5 μIU/ml); subclinical hypothyroidism (normal FT4, TSH between 5 μIU/ml and 10 μIU/ml) and central (secondary) hypothyroidism (low FT4 and normal or decreased TSH). Results: A total of 48 patients (22 males and 26 females) completed a 12 year-period of follow-up. During this period, hypothyroidism was diagnosed in 17/48 (35%) of patients. There was no significant difference in the prevalence in males 7/22 (32%) versus females 10/26 (38%). Sixteen of the patients had hypothyroidism after the age of 10 years (94%). The prevalence of overt hypothyroidism had risen from 0% at the age of 7 years to 35% at the age of 18 years. None of the patients had high anti-thyroperoxidase antibody titers. Out of 17 patients, 13 patients with hypothyroidism had normal or low TSH level (not appropriately elevated) indicative of defective hypothalamic pituitary response to low FT4 (central hypothyroidism). Three patients (6.3%) had subclinical hypothyroidism (TSH between 5 uIU/ml and 10 uIU/ml and normal FT4). The general trend of FT4 level showed progressive decrease over the 12 years, whereas, TSH levels did not show a corresponding increase. These data suggested defective hypothalamic pituitary thyroid axis involving both TSH and FT4 sretion in patients with thalassemia major over time. There was a significant negative correlation between serum ferritin and FT4 (r = −0.39, P = 0.007), but no correlation was

  20. DEHP reduces thyroid hormones via interacting with hormone synthesis-related proteins, deiodinases, transthyretin, receptors, and hepatic enzymes in rats.

    PubMed

    Liu, Changjiang; Zhao, Letian; Wei, Li; Li, Lianbing

    2015-08-01

    Di-(2-ethylhexyl) phthalate (DEHP) is used extensively in many personal care and consumer products, resulting in widespread nonoccupational human exposure through multiple routes and media. Limited studies suggest that exposure to DEHP may be associated with altered thyroid function, but detailed mechanisms are unclear. In order to elucidate potential mechanisms by which DEHP disturbs thyroid hormone homeostasis, Sprague-Dawley (SD) rats were dosed with DEHP by gavage at 0, 250, 500, and 750 mg/kg/day for 30 days and sacrificed within 24 h after the last dose. Gene expressions of thyroid hormone receptors, deiodinases, transthyretin, and hepatic enzymes were measured by RT-PCR; protein levels of transthyretin were also analyzed by Western blot. Results showed that DEHP caused histological changes in the thyroid and follicular epithelial cell hypertrophy and hyperplasia were observed. DEHP significantly reduced thyroid hormones (T3, T4) and thyrotropin releasing hormone (TRH) levels, whereas thyroid stimulating hormone (TSH) was not affected. After exposure to DEHP, biosynthesis of thyroid hormones was suppressed, and sodium iodide symporter (NIS) and thyroid peroxidase (TPO) levels were significantly reduced. Additionally, levels of deiodinases and transthyretin were also affected. TSH receptor (TSHr) level was downregulated, while TRH receptor (TRHr) level was upregulated. Metabolism of thyroid hormones was accelerated due to elevated gene expression of hepatic enzymes (UDPGTs and CYP2B1) by DEHP. Taken together, observed findings indicate that DEHP could reduce thyroid hormones through influencing biosynthesis, biotransformation, biotransport, receptor levels, and metabolism of thyroid hormones. PMID:25913319

  1. DEHP reduces thyroid hormones via interacting with hormone synthesis-related proteins, deiodinases, transthyretin, receptors, and hepatic enzymes in rats.

    PubMed

    Liu, Changjiang; Zhao, Letian; Wei, Li; Li, Lianbing

    2015-08-01

    Di-(2-ethylhexyl) phthalate (DEHP) is used extensively in many personal care and consumer products, resulting in widespread nonoccupational human exposure through multiple routes and media. Limited studies suggest that exposure to DEHP may be associated with altered thyroid function, but detailed mechanisms are unclear. In order to elucidate potential mechanisms by which DEHP disturbs thyroid hormone homeostasis, Sprague-Dawley (SD) rats were dosed with DEHP by gavage at 0, 250, 500, and 750 mg/kg/day for 30 days and sacrificed within 24 h after the last dose. Gene expressions of thyroid hormone receptors, deiodinases, transthyretin, and hepatic enzymes were measured by RT-PCR; protein levels of transthyretin were also analyzed by Western blot. Results showed that DEHP caused histological changes in the thyroid and follicular epithelial cell hypertrophy and hyperplasia were observed. DEHP significantly reduced thyroid hormones (T3, T4) and thyrotropin releasing hormone (TRH) levels, whereas thyroid stimulating hormone (TSH) was not affected. After exposure to DEHP, biosynthesis of thyroid hormones was suppressed, and sodium iodide symporter (NIS) and thyroid peroxidase (TPO) levels were significantly reduced. Additionally, levels of deiodinases and transthyretin were also affected. TSH receptor (TSHr) level was downregulated, while TRH receptor (TRHr) level was upregulated. Metabolism of thyroid hormones was accelerated due to elevated gene expression of hepatic enzymes (UDPGTs and CYP2B1) by DEHP. Taken together, observed findings indicate that DEHP could reduce thyroid hormones through influencing biosynthesis, biotransformation, biotransport, receptor levels, and metabolism of thyroid hormones.

  2. Thyroid hormone receptor can modulate retinoic acid-mediated axis formation in frog embryogenesis.

    PubMed Central

    Banker, D E; Eisenman, R N

    1993-01-01

    Thyroid hormone receptor acts as a hormone-dependent transcriptional transactivator and as a transcriptional repressor in the absence of thyroid hormone. Specifically, thyroid hormone receptor can repress retinoic acid-induced gene expression through interactions with retinoic acid receptor. (Retinoic acid is a potent teratogen in the frog Xenopus laevis, acting at early embryonic stages to interfere with the formation of anterior structures. Endogenous retinoic acid is thought to act in normal anterior-posterior axis formation.) We have previously shown that thyroid hormone receptor RNA (alpha isotype) is expressed and polysome-associated during Xenopus embryogenesis preceding thyroid gland maturation and endogenous thyroid hormone production (D. E. Banker, J. Bigler, and R. N. Eisenman, Mol. Cell. Biol. 11:5079-5089, 1991). To determine whether thyroid hormone receptor might influence the effects of retinoic acid in early frog development, we have examined the results of ectopic thyroid hormone receptor expression on retinoic acid teratogenesis. We demonstrate that microinjections of full-length thyroid hormone receptor RNA protect injected embryos from retinoic acid teratogenesis. DNA binding is apparently essential to this protective function, as truncated thyroid hormone receptors, lacking DNA-binding domains but including hormone-binding and dimerization domains, do not protect from retinoic acid. We have shown that microinjections of these dominant-interfering thyroid hormone receptors, as well as anti-thyroid hormone receptor antibodies, increase retinoic acid teratogenesis in injected embryos, presumably by inactivating endogenous thyroid hormone receptor. This finding suggests that endogenous thyroid hormone receptors may act to limit retinoic acid sensitivity. On the other hand, after thyroid hormone treatment, ectopic thyroid hormone receptor mediates teratogenesis that is indistinguishable from the dorsoanterior deficiencies produced in retinoic acid

  3. Infundibular tanycytes as modulators of neuroendocrine function: hypothetical role in the regulation of the thyroid and gonadal axis.

    PubMed

    Lechan, Ronald M; Fekete, Csaba

    2007-01-01

    Tanycytes comprise a heterogeneous population of specialized cells of glial origin that line the floor and ventrolateral walls of the third ventricle between the rostral and caudal limits of the hypothalamic median eminence. While morphologic and ultrastructural features suggest a role as barrier cells, creating separate compartments between the cerebrospinal fluid, median eminence and hypothalamus, tanycytes likely have multiple other important functions that have yet to be fully elucidated. Possibilities to consider are a role in neuroendocrine regulation including modulation of the hypothalamic-pituitary-thyroid axis during fasting and infection, regulation of reproductive function, particularly in seasonal breeders, and in feeding.

  4. Breed-specific reference intervals for assessing thyroid function in seven dog breeds.

    PubMed

    Hegstad-Davies, Rebecca L; Torres, Sheila M F; Sharkey, Leslie C; Gresch, Sarah C; Muñoz-Zanzi, Claudia A; Davies, Peter R

    2015-11-01

    Thyroxine (T4), free T4 (FT4), and thyrotropin (TSH) concentrations were measured in serum from 693 healthy representatives from 7 dog breeds (Alaskan Malamute, Collie, English Setter, Golden Retriever, Keeshond, Samoyed, or Siberian Husky) to determine whether breed-specific reference intervals (RIs) are warranted. Veterinarians reviewed the health history, performed a physical examination, and approved laboratory data for the enrolled dogs. Many purebred dogs had T4 and FT4 concentrations that were at, or below, the lower limits previously determined for non-breed-specific RIs. Mean concentrations of T4, FT4, and TSH varied significantly among breeds. The range of mean concentration of T4 (19.7 nmol/L [1.53 µg/dL] in English Setters to 29.0 nmol/L [2.25 µg/dL] in Keeshonds) and FT4 (12.6 pmol/L [0.98 ng/dL] in English Setters to 20.2 pmol/L [1.57 ng/dL] in Samoyeds) was considerable. Median TSH values ranged from 6.10 mIU/L (0.07 ng/mL; Alaskan Malamute and Golden Retriever) to 17.6 mIU/L (0.26 ng/mL; Collie). Mean T4 and FT4 concentrations were higher in females. Increasing age was associated with decreasing T4 and FT4, and increasing TSH concentration. The substantial ranges across breeds of measures of central tendency (mean, median) for all hormones indicate that breed-specific RIs are warranted. RIs encompassing the central 95% of reference values for all breeds combined, and for individual breeds, were calculated using nonparametric (TSH) and robust (T4, FT4) methods. Use of breed-specific RIs in combination with careful attention to the potential for pre-analytical and analytical variability in test results will improve thyroid function assessment in these breeds.

  5. Gender-specific regulation of response to thyroid hormone in aging

    PubMed Central

    2012-01-01

    Background Similar to other systems, the endocrine system is affected by aging. Thyroid hormone, the action of which is affected by many factors, has been shown to be associated with longevity. The most useful marker for the assessment of thyroid hormone action is TSH level. Although age and gender are believed to modify the pituitary set point or response to free thyroid hormone concentration, the precise age- and gender-dependent responses to thyroid hormone have yet to be reported. Methods We analyzed the results of 3564 thyroid function tests obtained from patients who received medication at both out- and inpatient clinics of Shinshu University Hospital. Subjects were from among those with thyroid function test results in the normal or mildly abnormal range. Based on a log-linear relationship between the concentrations of FHs and TSH, we established the putative resistance index to assess the relation between serum FH and TSH levels. Results Free thyroid hormone and TSH concentration showed an inverse log-linear relation. In males, there was a negative relationship between the free T3 resistance index and age. In females, although there were no relationships between age and FHs, the indices were positively related to age. Conclusions These findings indicated that there is a gender-specific response to thyroid hormone with aging. Although the TSH level is a useful marker for the assessment of peripheral thyroid hormone action, the values should be interpreted carefully, especially with regard to age- and gender-related differences. PMID:22280879

  6. Thyroid Function Status and Echocardiographic Abnormalities in Patients with Beta Thalassemia Major in Bahrain

    PubMed Central

    Garadah, Taysir S.; Mahdi, Najat A.; Jaradat, Ahmed M.; Hasan, Zuheir A.; Nagalla, Das S.

    2013-01-01

    Background: Thyroid gland dysfunction and echocardiographic cardiac abnormalities are well-documented in patients with transfusion dependent beta-thalassemia major (β-TM). Aim: This cross-sectional analytic study was conducted to investigate left ventricle (LV) diastolic and systolic function using pulsed Doppler (PD) and tissue Doppler (TD) echocardiography and correlate that with serum level thyroid stimulating hormone in patients with β-TM. Methods: The study was conducted on patients with β-TM (n = 110, age 15.9 ± 8.9 years) and compared with a control group (n = 109, age 15.8 ± 8.9 years). In all participants, echocardiographic indices of PD and TD were performed and blood samples were withdrawn for measuring the serum level of TSH, free T4, and ferritin. A linear regression analysis was performed on TSH level as the dependent variable and serum ferritin as independent. Stepwise multiple regression analysis was used to determine the odds ratio of different biochemical and echo variables on the risk of developing hypothyroidism. Results: Patients with β-TM compared with controls had thicker LV septal wall index (0.65 ± 0.26 vs. 0.44 ± 0.21 cm/M2, P < 0.001), posterior wall index (0.65 ± 0.23 vs. 0.43 ± 0.21 cm/m2, P < 0.01) and larger LVEDD index (4.35 ± 0.69 vs.3.88 ± 0.153 mm/m2, P < 0.001). In addition, β-TM patients had higher transmitral E wave velocity (E) (70.81 ± 10.13 vs. 57.53 ± 10.13 cm/s, P = 0.02) and E/A ratio (1.54 ± 0.18 vs. 1.23 ± 0.17, P < 0.01) and shorter deceleration time (DT) (170.53 ± 13.3 vs. 210.50 ± 19.20 m sec, P < 0.01). Furthermore, the ratio of transmitral E wave velocity to the tissue Doppler E wave at the basal septal mitral annulus (E/Em) was significantly higher in the β-TM group (19.68 ± 2.81 vs. 13.86 ± 1.41, P < 0.05). The tissue Doppler systolic wave (Sm) velocity and the early diastolic wave (Em) were significantly lower in the β-TM group compared with controls with Sm, 4.82 ± 1.2 vs. 6.22 ± 2.1 mm

  7. Alteration of Thyroid-Related Hormones within Normal Ranges and Early Functional Outcomes in Patients with Acute Ischemic Stroke.

    PubMed

    Xu, Xiao-Yan; Li, Wen-Yu; Hu, Xing-Yue

    2016-01-01

    This study evaluated the prognostic value of thyroid-related hormones within normal ranges after acute ischemic stroke. This was a retrospective study and we reviewed 1072 ischemic stroke patients consecutively admitted within 72 h after symptom onset. Total triiodothyronine (T3), total thyroxine (T4), free T3, free T4, and thyroid-stimulating hormone (TSH) were assessed to determine their values for predicting functional outcome at the first follow-up clinic visits, which usually occurred 2 to 4 weeks after discharge from the hospital. 722 patients were finally included. On univariate analysis, poor functional outcome was associated with presence of atrial fibrillation as the index event. Furthermore, score of National Institutes of Health Stroke Scale (NIHSS), total T4, free T4, and C-reactive protein at admission were significantly higher in patients with poor functional outcome, whereas free T3 and total T3 were significantly lower. On multiple logistic regression analysis, lower total T3 concentrations remained independently associated with poor functional outcome [odds ratio (OR), 0.10; 95% confidence interval (CI), 0.01-0.84; P = 0.035]. The only other variables independently associated with poor functional outcome were NIHSS scores. In sum, lower total T3 concentrations that were within the normal ranges were independently associated with poor short-term outcomes. PMID:27375741

  8. Kidney, thyroid and other organ functions after 40 years or more of lithium therapy: a case series of five patients.

    PubMed

    Permoda-Osip, Agnieszka; Abramowicz, Maria; Kraszewska, Agnieszka; Suwalska, Aleksandra; Chlopocka-Wozniak, Maria; Rybakowski, Janusz K

    2016-08-01

    We present the cases of five patients (two men aged 64 years and 79 years) and three women (aged 64 years, 65 years and 75 years) who have received lithium treatment for 40-45 years, with particular regard to kidney and thyroid functions, hypercalcaemia and cognition, in the context of disease course and overall functioning. Lithium was initiated in the early phase of the illness (in three patients within the first 2 years). In four patients, lithium concentration was between 0.60 and 0.65 mmol/l and in one patient, between 0.7 and 0.8 mmol/l. Four were very good lithium responders. One man had stage 3 chronic kidney disease, and the other stage 2/3 chronic kidney disease. All three women had asymptomatic stage 2 chronic kidney disease. One woman had severe thyroid dysfunction (Hashimoto's disease) with extremely high levels of antithyroid peroxidase antibodies and antithyroglobulin antibodies and was receiving thyroxine. Serum calcium levels were normal or borderline in all five patients, and most cognitive functions were comparable to healthy persons of similar gender, age and years of education. All the patients were professionally active until 55-65 years and their family and social functioning were satisfactory. It was concluded that, in good lithium responders, ultra-long-term treatment with lithium enables good professional and psychosocial functioning, and the possible somatic side effects are manageable. PMID:27536347

  9. Rapid and transient reduction in circulating thyroid hormones following systemic antigen priming: implications for functional collaboration between dendritic cells and thyroid.

    PubMed

    Bagriacik, E U; Zhou, Q; Wang, H C; Klein, J R

    2001-09-15

    The thyroid hormones T(3) (tri-iodothyronine) and T(4) (thyroxine) are disseminated throughout the body via the circulation and are maintained across a range of physiological concentrations under the control of thyroid-stimulating hormone (TSH). T(3) (and T(4) after conversion to T(3)) influences many biological activities, including gene expression and protein synthesis, though little is known about the nature of pituitary-thyroid immune interactions. In the present study we show that serum T(3) and T(4) levels are sharply but transiently reduced during the first 24 h of systemic antigen exposure and that this is followed by suppressed levels of free T(4), after which there is rapid recovery to normal levels. Splenic dendritic cells, depending upon the stage of maturation/activation, were found to be a rich source of TSH, and CD11c(+) cells with dendritic cell morphology were present in the thyroid 1-3 days after antigen exposure. Moreover, antigen priming of hypophysectomized mice that are unable to make pituitary-derived TSH resulted in significant increases in circulating T(4), implying that compensation in the drop in thyroid hormones can be regulated from extrapituitary sources. These findings thus identify a novel set of immune-endocrine interactions that transpire during the early phase of antigen exposure, and they suggest that under appropriate conditions the immune system directly participates in the process of maintaining physiological homeostasis by contributing to the regulatory control of thyroid hormone activity.

  10. Thyroid function and autoimmunity in children and adolescents with Type 1 Diabetes Mellitus.

    PubMed

    Riquetto, Aline Dantas Costa; de Noronha, Renata Maria; Matsuo, Eliza Mayumi; Ishida, Edson Jun; Vaidergorn, Rafael Eliahu; Soares Filho, Marcelo Dias; Calliari, Luis Eduardo Procópio

    2015-10-01

    We evaluated 233 children and adolescents with T1 Diabetes to analyze the prevalence and characteristics of Autoimmune Thyroid Disease. AITD was found in 23%, the majority being female and patients older than 5 years of age. Screening is mandatory, and the best approach could be guided by gender and age.

  11. 2,2",4,4"-TETRABROMODIPHENYL (PBDE 47) ALTERS THYROID FUNCTION IN THE RAT.

    EPA Science Inventory

    Two commercial PBDE mixtures, DE-71 and DE-79, cause dose-dependent depletion of serum T4 via induction of UGTs and increased CYP1A1 activity. This work characterized the effect of a major congener, PBDE-47, in DE-71 for effects on hepatic enzymes and thyroid hormones. Female 27...

  12. [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. PMID:27141586

  13. [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.

  14. 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

  15. Thyroid Disease and the Heart.

    PubMed

    Klein, Irwin; Danzi, Sara

    2016-02-01

    Thyroid hormones have an intimate relationship with cardiac function. Some of the most significant clinical signs and symptoms of thyroid disease are the cardiac manifestations. In both hypothyroidism and hyperthyroidism, the characteristic physiological effects of thyroid hormone can be understood from the actions at the molecular and cellular level. Here we explore topics from the metabolism and cellular effects of thyroid hormone to special considerations related to statin and amiodarone therapy for the alterations in thyroid hormone metabolism that accompany heart disease. PMID:26792255

  16. Effects of prolonged exposure to perchlorate on thyroid and reproductive function in zebrafish

    USGS Publications Warehouse

    Mukhi, S.; Patino, R.

    2007-01-01

    The objectives of this study were to determine the effects of prolonged exposure to perchlorate on (1) thyroid status and reproductive performance of adult zebrafish (Danio rerio) and (2) F1 embryo survival and early larval development. Using a static-renewal procedure, mixed sex populations of adult zebrafish were exposed to 0, 10, and 100 mg/l nominal concentrations of waterborne perchlorate for 10 weeks. Thyroid histology was qualitatively assessed, and females and males were separated and further exposed to their respective treatments for six additional weeks. Eight females in each tank replicate (n = 3) were paired weekly with four males from the same respective treatment, and packed-egg (spawn) volume (PEV) was measured each of the last five weeks. At least once during weeks 14-16 of exposure, other end points measured included fertilization rate, fertilized egg diameter, hatching rate, standard length, and craniofacial development of 4-day-postfertilization larvae and thyroid hormone content of 3.5-h embryos and of exposed mothers. At 10 weeks of exposure, perchlorate at both concentrations caused thyroidal hypertrophy and colloid depletion. A marked reduction in PEV was observed toward the end of the 6-week spawning period, but fertilization and embryo hatching rates were unaffected. Fertilized egg diameter and larval length were increased by parental exposure to perchlorate. Larval head depth was unaffected but the forward protrusion of the lower jaw-associated cartilage complexes, Meckel's and ceratohyal, was decreased. Exposure to both concentrations of perchlorate inhibited whole-body thyroxine content in mothers and embryos, but triiodothyronine content was unchanged. In conclusion, prolonged exposure of adult zebrafish to perchlorate not only disrupts their thyroid endocrine system but also impairs reproduction and influences early F1 development. ?? 2007 Oxford University Press.

  17. Implication of 18F-fluorodeoxyglucose uptake by affected lymph nodes in cases with differentiated thyroid cancer

    PubMed Central

    Fujii, Takaaki; Yajima, Reina; Tatsuki, Hironori; Kuwano, Hiroyuki

    2016-01-01

    In this study, we evaluated the usefulness of positron emission tomography using 18F-fluorodeoxyglucose (FDG-PET) to detect metastatic lymph nodes in differentiated thyroid cancer. We also investigated whether certain factors, including the size of the metastasis to the lymph nodes, are associated with FDG avidity. A total of 22 consecutive patients with differentiated thyroid cancer who underwent FDG-PET preoperatively were enrolled in this study. Lymph node metastasis was diagnosed in the final pathology in 10 of the 22 patients (45.5%). The mean maximum standardized uptake value of the metastatic lymph nodes was 4.53 (range, 0–23.5). The 22 cases with differentiated thyroid cancer were divided into two groups based on lymph node metastasis. Clinicopathological variables other than FDG uptake of metastatic lymph nodes were not predictors of lymph node metastasis of thyroid cancer. The sensitivity, specificity, overall accuracy and false-negative rates of preoperative FDG-PET in the prediction of lymph node status were 40.0, 100, 72.7 and 60.0%, respectively. The false-positive rate of FDG-PET evaluation was 0%. The mean largest dimension of metastasis was 23.0 mm for FDG-positive cases and 10.9 mm for FDG-negative cases. There was a marked difference in the size of metastases between FDG-positive and -negative cases; however, even in patients with node metastasis >10 mm, the false-negative rate was 50.0%. Therefore, FDG-PET imaging was not found to be sufficient for the evaluation of lymph node status, particularly in cases with small metastases. Our findings indicate that preoperative FDG-PET evaluation of the lymph nodes cannot be considered predictive of the final pathology. PMID:27600496

  18. The effects of atrazine metabolites on puberty and thyroid function in the male Wistar rat.

    PubMed

    Stoker, Tammy E; Guidici, D L; Laws, S C; Cooper, R L

    2002-06-01

    Recently we reported that atrazine (ATR), a chlorotriazine herbicide, alters the onset of puberty in male Wistar rats. In this study, we examined the same reproductive parameters in the developing male rat following a similar exposure to the primary, chlorinated metabolites of atrazine. Intact male Wistar rats were gavaged from postnatal day (PND) 23 through PND 53 and several reproductive endpoints were examined. The doses selected were the molar equivalents to atrazine in our previous work. Deethylatrazine (DEA), deisopropyl-atrazine (DIA), and diaminochlorotriazine (DACT) were administered by gavage at doses equivalent to the atrazine equimolar doses (AED) of 6.25, 12.5, 25, 50, 100, or 200 mg/kg. Preputial separation (PPS) was significantly delayed by DEA at 25, 100, and 200 AED, by DIA at 25, 100, and 200 AED, and by DACT at 12.5 through 200 AED. When the males were killed on PND 53, DEA (100 and 200 AED), DIA (50 through 200 AED), and DACT (200 AED) treatments caused a significant reduction in ventral prostate weight, while only the highest doses of DIA and DEA resulted in a significant decrease in lateral prostate weight. Seminal vesicle weight was reduced by DEA (25, 100, and 200 AED), DIA (100 and 200 AED), and 100 and 200 AED of DACT. Epididymal weights were reduced in the DEA (200 AED), DIA (200 AED), and DACT (100 and 200 AED) treatment groups. Serum testosterone was reduced only in the males receiving the 2 highest doses of DIA. Serum estrone was increased in the 2 highest doses of the DACT group, while serum estradiol was not different in any group. No differences were observed in any of the thyroid measures. In summary, the metabolites of ATR delay puberty in a manner similar to that observed in the previous study testing atrazine. These data also suggest that the 3 chlorinated metabolites are similar to ATR, by affecting the CNS control of the pituitary/gonadal axis and subsequent development of the reproductive tract.

  19. Positive and negative affective processing exhibit dissociable functional hubs during the viewing of affective pictures.

    PubMed

    Zhang, Wenhai; Li, Hong; Pan, Xiaohong

    2015-02-01

    Recent resting-state functional magnetic resonance imaging (fMRI) studies using graph theory metrics have revealed that the functional network of the human brain possesses small-world characteristics and comprises several functional hub regions. However, it is unclear how the affective functional network is organized in the brain during the processing of affective information. In this study, the fMRI data were collected from 25 healthy college students as they viewed a total of 81 positive, neutral, and negative pictures. The results indicated that affective functional networks exhibit weaker small-worldness properties with higher local efficiency, implying that local connections increase during viewing affective pictures. Moreover, positive and negative emotional processing exhibit dissociable functional hubs, emerging mainly in task-positive regions. These functional hubs, which are the centers of information processing, have nodal betweenness centrality values that are at least 1.5 times larger than the average betweenness centrality of the network. Positive affect scores correlated with the betweenness values of the right orbital frontal cortex (OFC) and the right putamen in the positive emotional network; negative affect scores correlated with the betweenness values of the left OFC and the left amygdala in the negative emotional network. The local efficiencies in the left superior and inferior parietal lobe correlated with subsequent arousal ratings of positive and negative pictures, respectively. These observations provide important evidence for the organizational principles of the human brain functional connectome during the processing of affective information.

  20. Does normal thyroid gland by ultrasonography match with normal serum thyroid hormones and negative thyroid antibodies?

    PubMed

    Trimboli, P; Rossi, F; Condorelli, E; Laurenti, O; Ventura, C; Nigri, G; Romanelli, F; Guarino, M; Valabrega, S

    2010-10-01

    Few papers have shown that a hypoechoic appearance of the thyroid gland at ultrasonography (US) is related to a hypofunction and serum positivity of thyroid antibodies (T-Ab). However, it is not ascertained if normal thyroid appearance at US correspond to normal thyroid laboratory tests. The aim of this study was to assess the value of normal thyroid at US in predicting normal thyroid hormones and negative T-Ab in a cohort of 48 adult patients. All patients (37 females and 11 males) were referred to our hospital to undergo their first thyroid US examination, followed by a thyroid function evaluation. All subjects had normal thyroid gland at US. As a control group 65 patients with hypoechoic and inhomogeneous thyroid gland were enrolled. All 48 patients had normal free-T (3) and free-T (4) levels. While 41 patients (85.4%) showed normal TSH, in 7 subjects (14.6%) TSH was elevated and a significant (p < 0.001) difference was recorded between the two groups in mean TSH value. Positive T-Ab value was found in 5 patients (10.4%) and the remaining 43 patients (89.6%) had negative T-Ab. TSH was not significantly correlated with age, thyroid volume or BMI. The multivariate model showed that only BMI was significantly correlated to thyroid volume (p < 0.01, r(2)=0.31). These results showed that normal thyroid recorded by US matches with normal thyroid laboratory assessment to a large degree. These preliminary data need to be confirmed in a prospective study and in a larger series and should suggest the evaluation of thyrotropin and thyroid antibodies in subjects with normal thyroid gland as assessed by US.

  1. Pediatric Thyroid Cancer

    MedlinePlus

    ... isthmus). The thyroid secretes three main hormones: 1) Thyroxine, that contains iodine, needed for growth and metabolism; ... also contains iodine and similar in function to Thyroxine; and 3) Calcitonin, which decreases the concentration of ...

  2. Serum thyroid-stimulating hormone levels are not associated with exercise capacity and lung function parameters in two population-based studies

    PubMed Central

    2014-01-01

    Background Thyroid dysfunction has been described to be linked to a variety of cardiovascular morbidities. Through this pathway thyroid function might also be associated with cardiorespiratory function and exercise capacity. So far only few patient-studies with small study populations investigated the association between thyroid dysfunction and exercise capacity. Thus, the aim of our study was to investigate the association of serum thyroid-stimulating hormone (TSH) levels with lung function and cardiopulmonary exercise testing (CPET) in the general population. Methods Data from the two independent cross-sectional population-based studies (Study of Health in Pomerania [SHIP] and SHIP-Trend-0) were pooled. SHIP was conducted between 2002 and 2006 and SHIP-Trend-0 between 2008 and 2012. Participants were randomly selected from population registries. In total, 4206 individuals with complete data were available for the present analysis. Thyroid function was defined based on serum TSH levels. Lung function was evaluated by forced expiratory volume in 1 s and forced vital capacity. CPET was based on symptom limited exercise tests on a bicycle in a sitting position according to a modified Jones protocol. Associations of serum TSH levels with lung function and CPET parameters were analysed by multivariable quantile regression adjusted for age, sex, height, weight, use of beta blockers, smoking status, and physical activity. Results Serum TSH levels, used as continuously distributed variable and categorized according to the clinical cut-offs 0.3 and 3.0 mIU/L or according to quintiles, were not consistently associated with parameters of lung function or CPET. Conclusions Our results suggest that thyroid dysfunction is not associated with lung function and cardiopulmonary exercise capacity in the general population. PMID:25182209

  3. Managing thyroid dysfunction in selected special situations

    PubMed Central

    2013-01-01

    Managing thyroid dysfunction is simple at first glance, the idea is to bring hormone levels in the euthyroid range, treat with antithyroid drugs, radio-iodine or surgery if toxic and replace with thyroxine or T3 if hypothyroid. Complexities arise when there are coexisting conditions that affect the thyroid or are affected by thyroid dysfunction and this review will deal with the special situations that need care when correcting thyroid hormone levels. PMID:23379325

  4. Thyroid disease

    SciTech Connect

    Falk, S.

    1990-01-01

    Presenting a multidisciplinary approach to the diagnosis and treatment of thyroid disease, this volume provides a comprehensive picture of current thyroid medicine and surgery. The book integrates the perspectives of the many disciplines that deal with the clinical manifestations of thyroid disorders. Adding to the clinical usefulness of the book is the state-of-the-art coverage of many recent developments in thyroidology, including the use of highly sensitive two-site TSH immunoradionetric measurements to diagnose thyroid activity; thyroglobulin assays in thyroid cancer and other diseases; new diagnostic applications of MRI and CT; treatment with radionuclides and chemotherapy; new developments in thyroid immunology, pathology, and management of hyperthyroidism; suppressive treatment with thyroid hormone; and management of Graves' ophthalmopathy. The book also covers all aspects of thyroid surgery, including surgical treatment of hyperthyroidism; papillary, follicular, and other carcinomas; thyroidectomy; and prevention and management of complications.

  5. Thyroid Problems

    MedlinePlus

    ... treated differently. Common thyroid disorders and problems include: Hypothyroidism Hypothyroidism is a disorder in which your thyroid doesn’ ... normal after you get better. If you have hypothyroidism, however, the levels of T4 in your blood ...

  6. Thyroid Antibodies

    MedlinePlus

    ... blocking production of thyroid hormones and resulting in hypothyroidism . TBII is not routinely tested, but TSI is ... autoimmune disease . A low level of thyroid hormones ( hypothyroidism ) can cause symptoms, such as: Weight gain Fatigue ...

  7. Thyroid Disease

    MedlinePlus

    ... base of your neck, just below your Adam's apple. This gland makes thyroid hormone that travels in ... base of your neck, just below your Adam's apple. This gland makes thyroid hormone that travels in ...

  8. Thyroid nodule

    MedlinePlus

    ... food Nodules that produce thyroid hormones will likely cause symptoms of overactive thyroid gland , including: Warm, sweaty skin Fast pulse Increased appetite Nervousness Restlessness Skin blushing or flushing Weight loss Irregular menstrual periods Older ...

  9. Thyroid Cancer

    MedlinePlus

    ... body work normally. There are several types of cancer of the thyroid gland. You are at greater ... imaging tests, and a biopsy to diagnose thyroid cancer. Treatment depends on the type of cancer you ...

  10. Structural functional associations of the orbit in thyroid eye disease: Kalman filters to track extraocular rectal muscles

    NASA Astrophysics Data System (ADS)

    Chaganti, Shikha; Nelson, Katrina; Mundy, Kevin; Luo, Yifu; Harrigan, Robert L.; Damon, Steve; Fabbri, Daniel; Mawn, Louise; Landman, Bennett

    2016-03-01

    Pathologies of the optic nerve and orbit impact millions of Americans and quantitative assessment of the orbital structures on 3-D imaging would provide objective markers to enhance diagnostic accuracy, improve timely intervention, and eventually preserve visual function. Recent studies have shown that the multi-atlas methodology is suitable for identifying orbital structures, but challenges arise in the identification of the individual extraocular rectus muscles that control eye movement. This is increasingly problematic in diseased eyes, where these muscles often appear to fuse at the back of the orbit (at the resolution of clinical computed tomography imaging) due to inflammation or crowding. We propose the use of Kalman filters to track the muscles in three-dimensions to refine multi-atlas segmentation and resolve ambiguity due to imaging resolution, noise, and artifacts. The purpose of our study is to investigate a method of automatically generating orbital metrics from CT imaging and demonstrate the utility of the approach by correlating structural metrics of the eye orbit with clinical data and visual function measures in subjects with thyroid eye disease. The pilot study demonstrates that automatically calculated orbital metrics are strongly correlated with several clinical characteristics. Moreover, it is shown that the superior, inferior, medial and lateral rectus muscles obtained using Kalman filters are each correlated with different categories of functional deficit. These findings serve as foundation for further investigation in the use of CT imaging in the study, analysis and diagnosis of ocular diseases, specifically thyroid eye disease.

  11. Structural Functional Associations of the Orbit in Thyroid Eye Disease: Kalman Filters to Track Extraocular Rectal Muscles

    PubMed Central

    Chaganti, Shikha; Nelson, Katrina; Mundy, Kevin; Luo, Yifu; Harrigan, Robert L; Damon, Steve; Fabbri, Daniel; Mawn, Louise; Landman, Bennett

    2016-01-01

    Pathologies of the optic nerve and orbit impact millions of Americans and quantitative assessment of the orbital structures on 3-D imaging would provide objective markers to enhance diagnostic accuracy, improve timely intervention and eventually preserve visual function. Recent studies have shown that the multi-atlas methodology is suitable for identifying orbital structures, but challenges arise in the identification of the individual extraocular rectus muscles that control eye movement. This is increasingly problematic in diseased eyes, where these muscles often appear to fuse at the back of the orbit (at the resolution of clinical computed tomography imaging) due to inflammation or crowding. We propose the use of Kalman filters to track the muscles in three-dimensions to refine multi-atlas segmentation and resolve ambiguity due to imaging resolution, noise, and artifacts. The purpose of our study is to investigate a method of automatically generating orbital metrics from CT imaging and demonstrate the utility of the approach by correlating structural metrics of the eye orbit with clinical data and visual function measures in subjects with thyroid eye disease. The pilot study demonstrates that automatically calculated orbital metrics are strongly correlated with several clinical characteristics. Moreover, the superior, inferior, medial and lateral rectus muscles obtained using Kalman filters are each correlated with different categories of functional deficit. These findings serve as foundation for further investigation in the use of CT imaging in the study, analysis and diagnosis of ocular diseases, specifically thyroid eye disease. PMID:27127330

  12. Iodotyrosine deiodinase, a novel target of environmental halogenated chemicals for disruption of the thyroid hormone system in mammals.

    PubMed

    Shimizu, Ryo

    2014-01-01

    Many synthetic chemicals have been identified as environmental contaminants with activity to disrupt normal function of the thyroid hormone system. Thyroid hormones play important roles in growth, development, differentiation, and basal metabolic homeostasis, as well as in brain development in human fetus and children, and thyroid dysfunction can have very serious consequences, including mental retardation. Environmental chemicals may affect thyroid hormone action in multiple ways, including reduced thyroid hormone synthesis owing to direct toxicity at the thyroid gland, interaction with thyroid hormone receptors and transporters such as transthyretin, and disturbance of thyroid hormone metabolism (e.g., glucuronidation, sulfation and deiodination). In addition, iodotyrosine deiodinase, which is involved in iodide salvage by catalyzing deiodination of iodinated by-products of thyroid hormone production, was recently identified as a possible new target for disruption of thyroid hormone homeostasis by environmental halogenated chemicals. This topic, after briefly summarizing findings on the thyroid hormone-disrupting action of environmental chemicals in mammals, focuses on the effects of environmental halogenated chemicals on iodotyrosine deiodinase activity. PMID:25177024

  13. Thyroid Emergencies.

    PubMed

    Leung, Angela M

    2016-01-01

    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

  14. 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

  15. Disruptive effects of persistent organohalogen contaminants on thyroid function in white whales (Delphinapterus leucas) from Svalbard.

    PubMed

    Villanger, G D; Lydersen, C; Kovacs, K M; Lie, E; Skaare, J U; Jenssen, B M

    2011-06-01

    We analysed levels of 56 organohalogen contaminants (OHCs) including brominated flame retardants, polychlorinated biphenyls (PCBs), and organochlorine pesticides in the blubber of white (beluga) whales (Delphinapterus leucas) from Svalbard, Norway (N=12; 6 adults [5 males and 1 female] and 6 subadults [4 males and 2 females]) collected in 1996-2001. We also measured circulating levels of thyroid hormones (THs) and thyroid stimulating hormone (TSH) in the whales. The results confirm that OHC levels in these white whales are among the highest levels recorded in wildlife from Svalbard, and at the high end of the range when compared to white whales from the North American Arctic. A projection to latent structure (PLS) model (subadults and adult males grouped together) revealed that known or suspected thyroid disruptive contaminants (polybrominated diphenylether [PBDE]-28, -47, -99, -100, and -154, hexachlorobenzene [HCB], and PCB-105) were negatively correlated with circulating levels of total thyroxin (TT4), free T4 (FT4) and free triiodothyronine (FT3). Most of these negative relationships were also confirmed using partial correlations controlling for length (and thus age) of the whales. The positive correlations of TT4, FT4 and FT3 with hexabromocyclododecane (HBCD), α-hexachlorocyclohexane (α-HCH), chlorinated bornanes CHB-40 and CHB-62 revealed by the PLS model were not confirmed by partial correlations. TH levels in the present study appeared to be somewhat lower than levels measured in beluga whales from the Canadian Arctic. However, we were not able to determine if this was caused by different levels of OHCs, or differences in biological factors (e.g. age, sex, moulting status, and season) and analytical methods between the studies. Although the sample sizes were low and statistical models cannot depict the biological cause-effect relationships, this study suggests negative influences of specific OHCs, particularly PBDEs, on thyroid hormone levels in white

  16. Disruptive effects of persistent organohalogen contaminants on thyroid function in white whales (Delphinapterus leucas) from Svalbard.

    PubMed

    Villanger, G D; Lydersen, C; Kovacs, K M; Lie, E; Skaare, J U; Jenssen, B M

    2011-06-01

    We analysed levels of 56 organohalogen contaminants (OHCs) including brominated flame retardants, polychlorinated biphenyls (PCBs), and organochlorine pesticides in the blubber of white (beluga) whales (Delphinapterus leucas) from Svalbard, Norway (N=12; 6 adults [5 males and 1 female] and 6 subadults [4 males and 2 females]) collected in 1996-2001. We also measured circulating levels of thyroid hormones (THs) and thyroid stimulating hormone (TSH) in the whales. The results confirm that OHC levels in these white whales are among the highest levels recorded in wildlife from Svalbard, and at the high end of the range when compared to white whales from the North American Arctic. A projection to latent structure (PLS) model (subadults and adult males grouped together) revealed that known or suspected thyroid disruptive contaminants (polybrominated diphenylether [PBDE]-28, -47, -99, -100, and -154, hexachlorobenzene [HCB], and PCB-105) were negatively correlated with circulating levels of total thyroxin (TT4), free T4 (FT4) and free triiodothyronine (FT3). Most of these negative relationships were also confirmed using partial correlations controlling for length (and thus age) of the whales. The positive correlations of TT4, FT4 and FT3 with hexabromocyclododecane (HBCD), α-hexachlorocyclohexane (α-HCH), chlorinated bornanes CHB-40 and CHB-62 revealed by the PLS model were not confirmed by partial correlations. TH levels in the present study appeared to be somewhat lower than levels measured in beluga whales from the Canadian Arctic. However, we were not able to determine if this was caused by different levels of OHCs, or differences in biological factors (e.g. age, sex, moulting status, and season) and analytical methods between the studies. Although the sample sizes were low and statistical models cannot depict the biological cause-effect relationships, this study suggests negative influences of specific OHCs, particularly PBDEs, on thyroid hormone levels in white

  17. Radioactive iodine therapy: Effect on functioning metastases of adenocarcinoma of the thyroid

    SciTech Connect

    Seidlin, S.M.; Marinelli, L.D.; Oshry, E. )

    1990-09-01

    A case of metastatic adenocarcinoma of the thyroid is reported in which treatment by means of radioactive iodine has been successful. The patient was completely thyroidectomized for malignant adenoma in 1923, with neither thyrotoxicosis then nor hypothyroidism postoperatively; 15 years later there developed classic symptoms of hyperthyroidism and severe pain in the lower back. In October 1939 a pulsating tumor removed from the level of the 12th thoracic vertebra proved to be metastatic thyroid adenocarcinoma (histologically well differentiated, with small follicles and colloid). In the next two years hyperthyroidism increased and roentgenograms revealed new metastases in the lungs, upper part of the right femur, second rib on the left side, left ilium, and skull. Roentgenologic irradiation of the metastases proved ineffectual. In March 1943 a tracer dose of radioactive iodine revealed iodine retention by all the known lesions and no evidence of residual thyroid tissue in the neck. Therapeutic amounts of radioactive iodine were administered orally between May and October 1943. Definite and lasting clinical improvement followed. In April 1944 and March 1945 additional I* was administered with a resultant disappearance of pain, increase in weight, and progressive change in all clinical criteria in the direction of hypothyroidism. Roentgenographic evidence pointed to an arrest if not a regression of the disease. No untoward effects followed this therapy. Radioactive iodine seems to be an effective therapeutic agent in the control of this type of tumor.

  18. Autoimmune Thyroid Disorders

    PubMed Central

    Iddah, M. A.; Macharia, B. N.

    2013-01-01

    Purpose of Review. Studies have been published in the field of autoimmune thyroid diseases since January 2005. The review is organized into areas of etiology, autoimmune features, autoantibodies, mechanism of thyroid cell injury, B-cell responses, and T-cell responses. Also it reviews the diagnosis and the relationship between autoimmune thyroid disease, neoplasm, and kidney disorders. Recent Findings. Autoimmune thyroid diseases have been reported in people living in different parts of the world including North America, Europe, Baalkans, Asia, Middle East, South America, and Africa though the reported figures do not fully reflect the number of people infected per year. Cases are unrecognized due to inaccurate diagnosis and hence are treated as other diseases. However, the most recent studies have shown that the human autoimmune thyroid diseases (AITDs) affect up to 5% of the general population and are seen mostly in women between 30 and 50 years. Summary. Autoimmune thyroid disease is the result of a complex interaction between genetic and environmental factors. Overall, this review has expanded our understanding of the mechanism involved in pathogenesis of AITD and the relationship between autoimmune thyroid disease, neoplasm, and kidney disease. It has opened new lines of investigations that will ultimately result in a better clinical practice. PMID:23878745

  19. [Thyroid cancer].

    PubMed

    Nagayama, Yuji

    2012-03-01

    The thyroid glands are a vulnerable organ to ionizing radiation. Indeed the epidemiological studies have revealed an increase in the incidences of thyroid cancer among atomic bomb survivors in Hiroshima and Nagasaki and radiation casualties in Chernobyl. The carcinogenic risk for the thyroids is dependent on radiation dose, and higher in younger people. Recent advances in molecular biology contribute to clarify the mechanisms for thyroid carcinogenesis at genetic and molecular levels. Here radiation-induced thyroid carcinogenesis is reviewed from epidemiological data to basic research.

  20. [Thyroid cancer].

    PubMed

    Nagayama, Yuji

    2012-03-01

    The thyroid glands are a vulnerable organ to ionizing radiation. Indeed the epidemiological studies have revealed an increase in the incidences of thyroid cancer among atomic bomb survivors in Hiroshima and Nagasaki and radiation casualties in Chernobyl. The carcinogenic risk for the thyroids is dependent on radiation dose, and higher in younger people. Recent advances in molecular biology contribute to clarify the mechanisms for thyroid carcinogenesis at genetic and molecular levels. Here radiation-induced thyroid carcinogenesis is reviewed from epidemiological data to basic research. PMID:22514922

  1. Thyroid status affects membranes susceptibility to free radicals and oxidative balance in skeletal muscle of Muscovy ducklings (Cairina moschata).

    PubMed

    Rey, Benjamin; Romestaing, Caroline; Bodennec, Jacques; Dumet, Adeline; Fongy, Anaïs; Duchamp, Claude; Roussel, Damien

    2014-10-01

    Thyroid hormones (TH) are major contributor to oxidative stress in mammals because they (1) stimulate reactive oxygen species generation (ROS), (2) impair antioxidant defenses, and (3) increase the susceptibility to free radicals of most tissues. Unlike mammals, THs seem to diminish mitochondrial ROS while they have limited effect on the antioxidant machinery in birds. However, how THs modify the susceptibility to ROS has never been explored in an avian model, and very little is known about their effect on oxidative balance in birds. Therefore, the objective of our study was to examine the effect of chronic pharmacological hypo- and hyperthyroidism on (i) the susceptibility of mitochondrial membranes to ROS; and (ii) the level of oxidative stress assessed by measuring oxidative damage to lipids, nucleic acids and proteins in the gastrocnemius muscle of ducklings. We show that hypothyroidism had no effect on the susceptibility of mitochondrial membranes to free radicals. Hypothyroid ducklings had lower oxidized lipids (-31%) and DNA (-25%) but a similar level of protein carbonylation relative to controls. Conversely, mitochondrial membranes of hyperthyroid ducklings exhibited higher unsaturation (+12%) and peroxidation (+31%) indexes than in controls indicating a greater susceptibility to free radicals. However, hyperthyroid ducklings exhibited more oxidative damages on proteins (+67%) only, whereas lipid damages remained unchanged, and there was a slight reduction (-15%) in damages to DNA compared to euthyroid controls. Our results indicate that birds and mammals present fundamental differences in their oxidative stress response to thyroid status.

  2. Pemphigus vulgaris with solitary toxic thyroid nodule.

    PubMed

    Alfishawy, Mostafa; Anwar, Karim; Elbendary, Amira; Daoud, Ahmed

    2014-01-01

    Background. Pemphigus vulgaris is an autoimmune vesiculobullous disease, affecting the skin and mucous membranes. It is reported to be associated with other autoimmune diseases including autoimmune thyroid diseases. However we report herein a case of pemphigus vulgaris associated with autonomous toxic nodule. Case Presentation. A 51-year-old woman was evaluated for blisters and erosions that develop on her trunk, face, and extremities, with a five-year history of progressively enlarging neck mass, and a past medical history of pemphigus vulgaris seven years ago. The condition was associated with palpitation, dyspnea, and heat intolerance. Thyroid function tests and thyroid scan were compatible with the diagnosis of thyrotoxicosis due to autonomous toxic nodule. Exacerbation of pemphigus vulgaris was proved by skin biopsy from the patient which revealed histologic picture of pemphigus vulgaris. Conclusion. Autoimmune thyroid diseases are reported to associate pemphigus vulgaris. To our knowledge, this case is the first in the English literature to report association between pemphigus vulgaris and autonomous toxic nodule and highlights the possibility of occurrence of pemphigus vulgaris with a nonautoimmune thyroid disease raising the question: is it just a coincidence or is there an explanation for the occurrence of both conditions together? PMID:25309761

  3. Affect integration and reflective function: clarification of central conceptual issues.

    PubMed

    Solbakken, Ole André; Hansen, Roger Sandvik; Monsen, Jon Trygve

    2011-07-01

    The importance of affect regulation, modulation or integration for higher-order reflection and adequate functioning is increasingly emphasized across different therapeutic approaches and theories of change. These processes are probably central to any psychotherapeutic endeavor, whether explicitly conceptualized or not, and in recent years a number of therapeutic approaches have been developed that explicitly target them as a primary area of change. However, there still is important lack of clarity in the field regarding the understanding and operationalization of affect integration, particularly when it comes to specifying underlying mechanisms, the significance of different affect states, and the establishment of operational criteria for measurement. The conceptual relationship between affect integration and reflective function thus remains ambiguous. The present article addresses these topics, indicating ways in which a more complex and exhaustive understanding of integration of affect, cognition and behavior can be attained.

  4. 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. PMID:25403287

  5. 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.

  6. How Does Maternal Employment Affect Children's Socioemotional Functioning?

    ERIC Educational Resources Information Center

    Lam, Gigi

    2015-01-01

    The maternal employment becomes an irreversible trend across the globe. The effect of maternal employment on children's socioemotional functioning is so pervasive that it warrants special attention to investigate into the issue. A trajectory of analytical framework of how maternal employment affects children's socioemotional functioning originates…

  7. 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.

  8. Thyroid hormone autoantibodies: are they a better marker to detect early thyroid damage in patients with hematologic cancers receiving tyrosine kinase inhibitor or immunoregulatory drug treatments?

    PubMed Central

    Mondello, P.; Mian, M.; Pitini, V.; Cuzzocrea, S.; Sindoni, A.; Galletti, M.; Mandolfino, M.; Santoro, D.; Mondello, S.; Aloisi, C.; Altavilla, G.; Benvenga, S.

    2016-01-01

    Background Unlike cytotoxic agents, novel antineoplastic drugs can variably affect thyroid function and so impair patient outcomes. However, the widely used standard thyroid tests have demonstrated low sensitivity for detecting early thyroid damage that leads to dysfunction of the gland. To find a more reliable thyroid marker, we assessed the presence of antibodies binding thyroid hormones (thAbs) in a cancer population undergoing potentially thyrotoxic treatment. Methods From April 2010 to September 2013, 82 patients with hematologic malignancies treated with tyrosine kinase inhibitors or immunoregulatory drugs were recruited. Healthy volunteers (n = 104) served as control subjects. Thyroid function, autoimmunity tests, thAbs, and thyroid sonography were assessed once during treatment. Results Overall, thAb positivity was recorded in 13% of the entire cohort. In most cases, the thAbs were of a single type, with a predominance of T3 immunoglobulin G. More specifically, thAbs were detected in 11 cancer patients; and abnormal levels of thyroid-stimulating hormone, thyroglobulin antibody, and thyroperoxidase antibody were detected in 6 (p = 0.05), 0 (p = 0.0006), and 2 cancer patients (p = 0.001) respectively. Ultrasonographic alterations of the thyroid were observed in 12 cancer patients. In contrast, of the 104 healthy control subjects, only 1 was positive for thAbs (1%). Conclusions We have demonstrated for the first time that thAbs are a reliable marker of early thyroid dysfunction when compared with the widely used standard thyroid tests. A confirmatory prospective trial aiming at evaluating thAbs at various time points during treatment could clarify the incidence and timing of antibody appearance. PMID:27330353

  9. [Thyroid and the environment].

    PubMed

    Brucker-Davis, Françoise; Hiéronimus, Sylvie; Fénichel, Patrick

    2016-01-01

    It has long been known that the thyroid depends upon the environment for regular iodine supply, avoiding iodine deficiency or excess. Thyroid function may be altered by natural compounds present in water or foodstuff (such as iodine or phyto-goitrogens), or by synthetic compounds, either administered knowingly (in case of medicine), or as an untoward event in case of exposure to industrial products and pesticides, massively produced and polluting the environment. Compounds with an impact on thyroid homeostasis are called thyroid disruptors (TD). TD may disrupt the thyroid economy at any level of regulation: thyroid hormone synthesis, metabolism, or transport; cellular level including thyroid hormone signaling; tumorigenesis or more indirectly via the triggering of an autoimmune process. Compounds such as polychlorinated biphenyls (PCBs) may act at multiple levels. PT effects on human health depend on parameters linked to the individual person (age at exposure, iodine status, diet, professional exposure, place of living, family history of thyroid disease, detoxification enzyme genetic variants) and on parameters linked to the compounds themselves (chemical structure, lipo- or hydro-solubility, modes of exposure, metabolites activity, "cocktail effect"). The toxic effects of TD do not necessarily follow the rules of classical toxicology (low-dose effects, non-monotonic curves). The main clinical risks are the deleterious impact on neurocognition and behavior for the fetus and the young child, and possibly the elderly, while in adults the main concerns are tumori/goitrogenesis and autoimmune thyroid disease. The potential socioeconomic impact for society warrants an active and major involvement in research to find solutions in a multidisciplinary approach. PMID:26603908

  10. [Thyroid and the environment].

    PubMed

    Brucker-Davis, Françoise; Hiéronimus, Sylvie; Fénichel, Patrick

    2016-01-01

    It has long been known that the thyroid depends upon the environment for regular iodine supply, avoiding iodine deficiency or excess. Thyroid function may be altered by natural compounds present in water or foodstuff (such as iodine or phyto-goitrogens), or by synthetic compounds, either administered knowingly (in case of medicine), or as an untoward event in case of exposure to industrial products and pesticides, massively produced and polluting the environment. Compounds with an impact on thyroid homeostasis are called thyroid disruptors (TD). TD may disrupt the thyroid economy at any level of regulation: thyroid hormone synthesis, metabolism, or transport; cellular level including thyroid hormone signaling; tumorigenesis or more indirectly via the triggering of an autoimmune process. Compounds such as polychlorinated biphenyls (PCBs) may act at multiple levels. PT effects on human health depend on parameters linked to the individual person (age at exposure, iodine status, diet, professional exposure, place of living, family history of thyroid disease, detoxification enzyme genetic variants) and on parameters linked to the compounds themselves (chemical structure, lipo- or hydro-solubility, modes of exposure, metabolites activity, "cocktail effect"). The toxic effects of TD do not necessarily follow the rules of classical toxicology (low-dose effects, non-monotonic curves). The main clinical risks are the deleterious impact on neurocognition and behavior for the fetus and the young child, and possibly the elderly, while in adults the main concerns are tumori/goitrogenesis and autoimmune thyroid disease. The potential socioeconomic impact for society warrants an active and major involvement in research to find solutions in a multidisciplinary approach.

  11. A model of the development of the brain as a construct of the thyroid system.

    PubMed Central

    Howdeshell, Kembra L

    2002-01-01

    Thyroid hormone is essential for normal brain development. However, little is known about the molecular and cellular mechanisms that mediate thyroid hormone action on the developing brain or the developmental events selectively affected. Consequently, although a large number of environmental chemicals interfere with the thyroid system, there are few neurodevelopmental end points to recruit for toxicological studies. Therefore, my goal here is to review what is known about the relative timing of normal brain construction and thyroid system development, with special focus on the period of in utero development in humans and the comparable developmental period in laboratory rats. These data are presented as a timeline to aid in the identification of thyroid-sensitive end points in brain development and to highlight important data gaps. I discuss the known influence of certain synthetic chemicals on the thyroid system and include a brief review of the effects of developmental exposure to chemicals on thyroid system function. The relationship between the thyroid hormone and retinoic acid systems, as well as the thyroid hormone sensitivity of the developing cochlea, is also discussed. PMID:12060827

  12. Selenium and Iodine in Autoimmune Thyroiditis.

    PubMed

    Guastamacchia, Edoardo; Giagulli, Vito Angelo; Licchelli, Brunella; Triggiani, Vincenzo

    2015-01-01

    Selenium and iodine are essential for thyroid hormone synthesis and function. Selenium, in form of selenocysteine, is found either in the catalytic center of enzymes involved in the protection of the thyroid gland from free radicals originating during thyroid hormone synthesis, and in three different iodothyronine deiodinases catalyzing the activation and the inactivation of thyroid hormones. Iodine is an essential constituent of thyroid hormones and its deficiency causes different disorders that include goiter, hypothyroidism, reduced fertility and alteration in growth, physical and neurological development. These two micronutrients could be involved in the pathogenesis of autoimmune thyroid diseases, a spectrum of pathological conditions including Hashimoto's thryoiditis, post-partum thyroiditis, the so-called painless thyroiditis, Graves' disease and Graves' ophtalmopathy. Aim of this paper is to review the role played by selenium and iodine in autoimmune thyroiditis.

  13. Clinicoepidemiological Observational Study of Acquired Alopecias in Females Correlating with Anemia and Thyroid Function

    PubMed Central

    Deo, Kirti; Sharma, Yugal K.; Wadhokar, Meenakshi; Tyagi, Neha

    2016-01-01

    Alopecia can either be inherited or acquired; the latter, more common, can be diffuse, patterned, and focal, each having cicatricial and noncicatricial forms. This observational study of 135 cases in a semiurban Indian population aimed to detect the prevalence of various forms of acquired alopecia in females and correlate the same with levels of hemoglobin, serum ferritin, triiodothyronine, thyroxin, and thyroid stimulating hormone. The majority (84, 62.2%) of our cases of alopecia had telogen effluvium followed by female pattern alopecia (32, 23.7%). Stress (86, 63.7%), topical application of chemicals (72, 53.3%), systemic medications for concurrent illnesses (62, 5%), and pregnancy (14, 10.3%) were the common exacerbating factors. Neither low hemoglobin (<12 gm%, 73.4%) nor low serum ferritin (<12 μg/L, 6.7%) was found to be statistically significant. A majority (90, 90.9%) of 99 cases with anemia (hemoglobin levels of <12 gm%) had serum ferritin levels >12 μg/L. Though lack of vitamin B12 testing was a limitation of our study, its deficiency could be the probable cause of iron deficiency as the majority (58, 64.4%) of these cases, as indeed majority (89, 65.4%) of our study population, were vegetarians. Thyroid disorders (23, 17%, including 9 newly diagnosed) were not of significance statistically. PMID:26904106

  14. Mechanistic aspects of ingested chlorine dioxide on thyroid function: impact of oxidants on iodide metabolism

    SciTech Connect

    Bercz, J.P.; Jones, L.L.; Harrington, R.M.; Bawa, R.; Condie, L.

    1986-11-01

    Toxicological studies dealing with recent findings of health effects of drinking water disinfectants are reviewed. Experiments with monkeys and rodents indicate that the biological activity of ingested disinfectants is expressed via their chemical interaction with the mucosal epithelia, secretory products, and nutritional contents of the alimentary tract. Evidence exists that a principal partner of this redox interaction is the iodide of nutritional origin that is ubiquitous in the gastrointestinal tract. Thus the observation that subchronic exposure to chlorine dioxide (ClO/sub 2/) in drinking water decreases serum thyroxine levels in mammalian species can be best explained with changes produced in the chemical form of the bioavailable iodide. Ongoing and previously reported mechanistic studies indicate that oxidizing agents such as chlorine-based disinfectants oxidize the basal iodide content of the gastrointestinal tract. The resulting reactive iodine species readily attaches to organic matter by covalent bonding. Evidence suggests that the extent to which such iodinated organics are formed is proportional to the magnitude of the electromotive force and stoichiometry of the redox couple between iodide and the disinfectant. Because the extent of thyroid uptake of the bioavailable iodide does not decrease during ClO/sub 2/ ingestion, it seems that ClO/sub 2/ does not cause iodide deficiency of sufficient magnitude to account for the decease in hormonogenesis. Absorption of one or more of iodinated molecules, e.g., nutrient, hormones, or cellular constituents of the alimentary tract having thyromimetic or thyroid inhibitory properties, is a better hypothesis for the effects seen.

  15. Thyroid function and reproductive success in rodents exposed to perchlorate via food and water.

    PubMed

    Smith, Philip N; Severt, Scott A; Jackson, J W Andrew; Anderson, Todd A

    2006-04-01

    The purpose of the present study was to determine if exposure to perchlorate via food items would have effects on mammals similar to those caused by exposure through drinking water at approximately equivalent doses. Prairie voles (Microtus ochrogaster) and deer mice (Peromyscus maniculatus) were used to assess the potential toxicity of perchlorate-contaminated food items. Voles and mice were divided randomly into three treatment groups--perchlorate-contaminated food (PCF), perchlorate-contaminated water (PCW), and control groups--such that each treatment group contained equal numbers of males and females. Rodents in PCF treatment groups were fed chow formulated with soybean plant matter that had been grown with perchlorate-contaminated irrigation water. Individuals in the control and PCF groups were provided distilled/deionized drinking water, whereas the PCW group received drinking water containing sodium perchlorate. Only slight differences among treatment groups were observed in a variety of endpoints, including reproductive success, tissue perchlorate concentrations, thyroid hormone concentrations, and thyroid histology. However, trends observed in the present study suggest that perchlorate exposure via water may result in slightly greater effects than exposure to perchlorate via food. These data and recent reports of perchlorate in a wide variety of food items indicate that exposure via food intake is an important consideration when examining cumulative risk among humans, livestock, and wildlife.

  16. Epidemiological trends of iodine-related thyroid disorders: an example from Slovenia.

    PubMed

    Gaberšček, Simona; Zaletel, Katja

    2016-06-01

    The epidemiology of thyroid disorders is significantly associated with iodine supply. In 1999, Slovenia increased iodine content in kitchen salt from 10 mg to 25 mg of potassium iodide per kg of salt. According to the WHO criteria, Slovenia shifted from a mildly iodine-deficient country to a country with adequate iodine intake. Ten years after the increase in iodine intake, the incidence of diffuse goitre and thyroid autonomy decreased. Now patients with diffuse goitre and thyroid autonomy reach older age than the patients before the increase in iodine intake. In addition, patients with thyroid autonomy are less frequently hyperthyroid than ten years ago and iodine-induced hyperthyroidism is less severe. The incidence of highly malignant thyroid carcinoma has also dropped. However, the incidence of Hashimoto's thyroiditis increased, most probably in genetically predisposed individuals. Over the last ten years, many animal and in vitro studies evaluated the effects of endocrine disrupting chemicals (EDC) on various aspects of the thyroid function. They mostly studied the effects of polychlorinated biphenyls (PCBs) and dioxins, brominated flame retardants, phthalates, bisphenol A, perfluorinated chemicals, and perchlorate. However, human studies on the effects of EDCs on the thyroid function are very scarce, especially the long-term ones. What they do suggest is that PCBs and dioxins interfere with the transport of thyroid hormones and adversely affect the thyroid function. Many authors agree that iodine deficiency predisposes the thyroid gland to harmful effects of EDCs. Therefore the effects of EDCs in iodine-deficient areas could be more severe than in areas with adequate iodine intake. PMID:27331296

  17. [Postpartum thyroiditis. A review].

    PubMed

    Hurtado-Hernández, Z; Segura-Domínguez, A

    2013-01-01

    Postpartum thyroiditis (PPT) is a transient thyroid dysfunction of autoimmune origin that can occur in the first year postpartum in women who have not been previously diagnosed with thyroid disease. It may start with clinical thyrotoxicosis followed by hypothyroidism and the subsequent recovery of thyroid function, or may just appear as isolated thyrotoxicosis or hypothyroidism. PPT recurs in high percentage of patients after subsequent pregnancies. Many women develop permanent hypothyroidism sometime during the 3 to 10 year period after an episode of PPT. It is important for family physicians to be familiar with this disease, due to its high prevalence in order to make a correct diagnosis and therapeutic intervention. Family doctors also play a crucial role in the monitoring of these patients, given the negative implications of established hypothyroidism on reproduction in the female population during their reproductive years. This article reviews the principle characteristics of PPT along with its diagnosis and treatment. PMID:23834978

  18. Assessment of petroleum streams for thyroid toxicity.

    PubMed

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

    2016-07-01

    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.

  19. Thyroid dysfunction and pregnancy outcomes

    PubMed Central

    Nazarpour, Sima; Ramezani Tehrani, Fahimeh; Simbar, Masoumeh; Azizi, Fereidoun

    2015-01-01

    Background: Pregnancy has a huge impact on the thyroid function in both healthy women and those that have thyroid dysfunction. The prevalence of thyroid dysfunction in pregnant women is relatively high. Objective: The objective of this review was to increase awareness and to provide a review on adverse effect of thyroid dysfunction including hyperthyroidism, hypothyroidism and thyroid autoimmune positivity on pregnancy outcomes. Materials and Methods: In this review, Medline, Embase and the Cochrane Library were searched with appropriate keywords for relevant English manuscript. We used a variety of studies, including randomized clinical trials, cohort (prospective and retrospective), case-control and case reports. Those studies on thyroid disorders among non-pregnant women and articles without adequate quality were excluded. Results: Overt hyperthyroidism and hypothyroidism has several adverse effects on pregnancy outcomes. Overt hyperthyroidism was associated with miscarriage, stillbirth, preterm delivery, intrauterine growth retardation, low birth weight, preeclampsia and fetal thyroid dysfunction. Overt hypothyroidism was associated with abortion, anemia, pregnancy-induced hypertension, preeclampsia, placental abruption, postpartum hemorrhage, premature birth, low birth weight, intrauterine fetal death, increased neonatal respiratory distress and infant neuro developmental dysfunction. However the adverse effect of subclinical hypothyroidism, and thyroid antibody positivity on pregnancy outcomes was not clear. While some studies demonstrated higher chance of placental abruption, preterm birth, miscarriage, gestational hypertension, fetal distress, severe preeclampsia and neonatal distress and diabetes in pregnant women with subclinical hypothyroidism or thyroid autoimmunity; the other ones have not reported these adverse effects. Conclusion: While the impacts of overt thyroid dysfunction on feto-maternal morbidities have been clearly identified and its long

  20. Thyroid Dysfunction and Autoantibodies Association with Hypertensive Disorders during Pregnancy

    PubMed Central

    Alavi, Azin; Adabi, Khadijeh; Nekuie, Sepideh; Jahromi, Elham Kazemi; Solati, Mehrdad; Sobhani, Alireza; Karmostaji, Hoda; Jahanlou, Alireza Shahab

    2012-01-01

    Background. Thyroid dysfunction and autoimmunity are relatively common in reproductive age and have been associated with adverse health outcomes for both mother and child, including hypertensive disorders during pregnancy. Objective. To survey the relation between thyroid dysfunction and autoimmunity and incidence and severity of pregnancy-induced hypertensive disorders. Method. In this case control study 48 hypertensive patients in 4 subgroups (gestational hypertension, mild preeclampsia, severe preeclampsia, eclampsia) and 50 normotensive ones were studied. The samples were nulliparous and matched based on age and gestational age and none of them had previous history of hypertensive or thyroid disorders and other underlying systemic diseases or took medication that might affect thyroid function. Their venous blood samples were collected using electrochemiluminescence and ELISA method and thyroid hormones and TSH and autoantibodies were measured. Results. Hypertensive patients had significant lower T3 concentration compared with normotensive ones with mean T3 values 152.5 ± 48.93 ng/dL, 175.36 ± 58.07 ng/dL respectively. Anti-TPO concentration is higher in control group 6.07 ± 9.02 IU/mL compared with 2.27 ± 2.94 IU/mL in cases. Conclusion. The severity of preeclampsia and eclampsia was not associated with thyroid function tests. The only significant value was low T3 level among pregnancy, induced hypertensive patients. PMID:22848832

  1. Effect of chronic douching with polyvinylpyrrolidone-iodine on iodine absorption and thyroid function

    SciTech Connect

    Safran, M.; Braverman, L.E.

    1982-07-01

    Daily vaginal douching with polyvinylpyrrolidone-iodine in 12 euthyroid volunteers for 14 days resulted in a significant increase in serum total iodine concentration and urine iodine excretion. The increase in serum total iodine was associated with a marked decrease in 24-hour /sup 123/I uptake by the thyroid and a small but significant increase in serum thyrotropin (TSH) concentration. However, values for serum TSH never rose above the normal range. No significant changes in serum thyroxine (T4), free T4 index (FTI), or triiodothyronine concentrations were observed, although serum T4 and FTI did decrease slightly during treatment. The findings suggest that iodine is absorbed across the vaginal mucosa and that the subsequent increase in serum total iodine does induce subtle increases in serum TSH concentration. There was no evidence, however, of overt hypothyroidism in these euthyroid women.

  2. Effects of bedrest and centrifugation of humans on serum thyroid function tests.

    NASA Technical Reports Server (NTRS)

    Leach, C. S.; Johnson, P. C.; Driscoll, T. B.

    1972-01-01

    Changes in plasma volume and protein concentration have been reported when normal subjects are bedrested or centrifuged. Since thyroid hormones are transported by specific plasma proteins, each of these procedures could be expected to change plasma levels of these hormones. In this study centrifugation of normal healthy human subjects produced an increased concentration of total protein and albumin. When these same subjects were bedrested for six days, no change in total protein, albumin or thyroxine binding globulin were found although there was an eight per cent decrease in plasma volume. Centrifugation and, to a lesser extent, bedrest produced changes in serum T-4 levels and the T-3 test results. The direction of these changes (decreased % T-3 values and increased T-4 levels) indicate that these two situations produce an increased plasma concentration of thyroxine binding sites.

  3. Altered thyroid axis function in Lewis rats with genetically defective hypothalamic CRH/VP neurosecretory cells.

    PubMed

    Whitnall, M H; Smallridge, R C

    1997-11-01

    Lewis rats display hyporesponsive hypothalamo-pituitary-adrenocortical (HPA) axes, overproduction of cytokines, and susceptibility to inflammatory disease. The Lewis corticotropin-releasing hormone (CRH) neurosecretory system contains normal numbers of vasopressin (VP)-deficient axon varicosities, but abnormally sparse VP-containing varicosities in the external zone of the median eminence, compared to the normoresponsive Sprague Dawley (SD), Wistar and Fischer 344 strains. Since VP may act as a thyrotropin-releasing factor, we hypothesized that thyroid axis responsivity may be altered in Lewis rats. T3, T4 and TSH were measured by radioimmunoassay, and free T4 by equilibrium dialysis, in adult male Lewis and SD rats. One h cold (5 degrees C) induced significant increases in T3, T4 and TSH levels in Lewis rats but not in SD rats. Ninety min insulin-induced hypoglycemia (1 IU/kg, i.p.) induced a significant T3 increase in Lewis rats and a significant T4 increase in SD rats. Two h after ip LPS (0.25 or 0.75 mg/kg), T4 levels fell significantly in Lewis rats but not in SD rats. TSH decreases were significant in Lewis rats after 0.75 mg/kg and in SD rats after 0.25 mg/kg. Baseline hormone levels were generally higher in Lewis rats; the differences were significant for T3 and T4 in the insulin experiments and for T3, T4 and free T4 in the LPS experiments. The data suggest that reduced inhibition from the adrenocortical axis in Lewis rats leads to hyperresponsivity of the thyroid axis to cold, and greater LPS-induced decreases in T4 levels, probably due to an exaggerated inhibitory cytokine response.

  4. Long-term follow-up of thyroid nodule growth.

    PubMed

    Quadbeck, B; Pruellage, J; Roggenbuck, U; Hirche, H; Janssen, O E; Mann, K; Hoermann, R

    2002-10-01

    Benign thyroid nodules are common in iodine deficient countries. Although many recent studies have addressed the molecular basis and short-term outcome of treatment in nodular thyroid disease, data on the long-term follow-up of thyroid nodule growth are widely lacking. The aim of the present study was to evaluate the long-term behaviour of benign thyroid nodules growth. We followed 109 consecutive patients seen at yearly intervals in our Outpatient Clinic for at least 3 years (range 3-12 years, mean 4.9 +/- 2.6 years) presenting with 139 benign nodules in uni- or multinodular goiters. The size of the nodules and thyroid glands was analysed retrospectively. The study included a spectrum of benign thyroid nodules, 86 functioning and 53 non-functioning. 27 patients were treated with levothyroxine, 8 with iodide and 16 with a combination of both. 58 patients were not treated mainly because of thyroid functional autonomy. Patients with overt hyperthyroidism or suspected malignancy by fine-needle aspiration were excluded from the study. The nodules and glands were assessed by ultrasonography at yearly intervals and documented by photoprints. Relevant growth was defined as an increase in nodule volume of at least 30%. For statistical analyses, Cox Proportional Hazard Model and life-table analyses according to Kaplan-Meier were performed. Most thyroid nodules grew slowly but continuously during follow-up. After about 3 years, half of the nodules had increased their volume by at least 30%. Growth of the nodules was significantly faster than of the corresponding thyroid glands (p < 0.0001). Age and sex of the patients and size or function of the nodules at initial presentation were not significantly related to their growth. Suppression of TSH did not affect growth of the nodules irrespective of the source of thyroid hormones, endogenous or by administration of levothyroxine. In conclusion, benign thyroid nodules have a slow intrinsic growth potential, which is apparently

  5. Effects of 3,5-Diiodotyrosine and Potassium Iodide on Thyroid Function and Oxidative Stress in Iodine-Excess Wistar Rats.

    PubMed

    Liu, Dan; Lin, Xinying; Yu, Fugui; Zhang, Man; Chen, Hongxia; Bao, Wei; Wang, Xia

    2015-12-01

    The objective of this study was to investigate the effects of organic iodine (3,5-diiodotyrosine, DIT) and inorganic iodine (potassium iodine, KI) on thyroid function and oxidative stress in iodine-excess Wistar rats. Seventy-two Wistar rats were randomly divided into eight groups: normal control (NC), thyroid tablet-induced hyperthyroidism model (HM), low DIT (L-DIT), medium DIT (M-DIT), high DIT (H-DIT), low KI (L-KI), medium KI (M-KI), and high KI (H-KI). All rats were fed ad libitum for 30 days. Morphological changes in the thyroid, absolute and relative weights of the thyroid, thyroid function markers free triiodothyronine (FT3) and free thyroxine (FT4), urinary iodine level, and oxidative stress indicators were measured. Compared to the HM groups, the FT3 and FT4 levels decreased in the L-DIT groups; the thyroid weight and thyroid weight/body weight values decreased markedly in the L-DIT and M-DIT groups; serum superoxide dismutase/malondialdehyde increased markedly; glutathione peroxidase activity increased markedly in the L-DIT groups; and malondialdehyde levels decreased significantly in the M-DIT groups. However, the FT3 and FT4 levels decreased and glutathione peroxidase levels increased significantly in the DIT groups compared to their corresponding KI groups. Additionally, urinary iodine levels increased significantly in both DIT and KI groups, while the highest urinary iodine excretion was showed in the DIT groups among groups. When the addition of iodine with the same doses in iodine-excess rats, although neither DIT nor KI normalized iodine levels in the iodine-excess rats, the DIT did less damage than did KI to thyroid follicular cells. Therefore, DIT rather than KI had a protective effect by balancing the antioxidant system when exposed to supraphysiological iodine. These suggest that DIT may be used as a new alternative iodized salt in the universal salt iodization to avoid the potential damage of surplus KI. PMID:26002813

  6. Effects of 3,5-Diiodotyrosine and Potassium Iodide on Thyroid Function and Oxidative Stress in Iodine-Excess Wistar Rats.

    PubMed

    Liu, Dan; Lin, Xinying; Yu, Fugui; Zhang, Man; Chen, Hongxia; Bao, Wei; Wang, Xia

    2015-12-01

    The objective of this study was to investigate the effects of organic iodine (3,5-diiodotyrosine, DIT) and inorganic iodine (potassium iodine, KI) on thyroid function and oxidative stress in iodine-excess Wistar rats. Seventy-two Wistar rats were randomly divided into eight groups: normal control (NC), thyroid tablet-induced hyperthyroidism model (HM), low DIT (L-DIT), medium DIT (M-DIT), high DIT (H-DIT), low KI (L-KI), medium KI (M-KI), and high KI (H-KI). All rats were fed ad libitum for 30 days. Morphological changes in the thyroid, absolute and relative weights of the thyroid, thyroid function markers free triiodothyronine (FT3) and free thyroxine (FT4), urinary iodine level, and oxidative stress indicators were measured. Compared to the HM groups, the FT3 and FT4 levels decreased in the L-DIT groups; the thyroid weight and thyroid weight/body weight values decreased markedly in the L-DIT and M-DIT groups; serum superoxide dismutase/malondialdehyde increased markedly; glutathione peroxidase activity increased markedly in the L-DIT groups; and malondialdehyde levels decreased significantly in the M-DIT groups. However, the FT3 and FT4 levels decreased and glutathione peroxidase levels increased significantly in the DIT groups compared to their corresponding KI groups. Additionally, urinary iodine levels increased significantly in both DIT and KI groups, while the highest urinary iodine excretion was showed in the DIT groups among groups. When the addition of iodine with the same doses in iodine-excess rats, although neither DIT nor KI normalized iodine levels in the iodine-excess rats, the DIT did less damage than did KI to thyroid follicular cells. Therefore, DIT rather than KI had a protective effect by balancing the antioxidant system when exposed to supraphysiological iodine. These suggest that DIT may be used as a new alternative iodized salt in the universal salt iodization to avoid the potential damage of surplus KI.

  7. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    PubMed Central

    Drozd, Valentina M.; Saenko, Vladimir A.; Brenner, Alina V.; Drozdovitch, Vladimir; Pashkevich, Vasilii I.; Kudelsky, Anatoliy V.; Demidchik, Yuri E.; Branovan, Igor; Shiglik, Nikolay; Rogounovitch, Tatiana I.; Yamashita, Shunichi; Biko, Johannes; Reiners, Christoph

    2015-01-01

    One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer. PMID:26397978

  8. Major Factors Affecting Incidence of Childhood Thyroid Cancer in Belarus after the Chernobyl Accident: Do Nitrates in Drinking Water Play a Role?

    PubMed

    Drozd, Valentina M; Saenko, Vladimir A; Brenner, Alina V; Drozdovitch, Vladimir; Pashkevich, Vasilii I; Kudelsky, Anatoliy V; Demidchik, Yuri E; Branovan, Igor; Shiglik, Nikolay; Rogounovitch, Tatiana I; Yamashita, Shunichi; Biko, Johannes; Reiners, Christoph

    2015-01-01

    One of the major health consequences of the Chernobyl Nuclear Power Plant accident in 1986 was a dramatic increase in incidence of thyroid cancer among those who were aged less than 18 years at the time of the accident. This increase has been directly linked in several analytic epidemiological studies to iodine-131 (131I) thyroid doses received from the accident. However, there remains limited understanding of factors that modify the 131I-related risk. Focusing on post-Chernobyl pediatric thyroid cancer in Belarus, we reviewed evidence of the effects of radiation, thyroid screening, and iodine deficiency on regional differences in incidence rates of thyroid cancer. We also reviewed current evidence on content of nitrate in groundwater and thyroid cancer risk drawing attention to high levels of nitrates in open well water in several contaminated regions of Belarus, i.e. Gomel and Brest, related to the usage of nitrogen fertilizers. In this hypothesis generating study, based on ecological data and biological plausibility, we suggest that nitrate pollution may modify the radiation-related risk of thyroid cancer contributing to regional differences in rates of pediatric thyroid cancer in Belarus. Analytic epidemiological studies designed to evaluate joint effect of nitrate content in groundwater and radiation present a promising avenue of research and may provide useful insights into etiology of thyroid cancer.

  9. 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...

  10. Disruption of thyroid hormone functions by low dose exposure of tributyltin: an in vitro and in vivo approach.

    PubMed

    Sharan, Shruti; Nikhil, Kumar; Roy, Partha

    2014-09-15

    Triorganotins, such as tributyltin chloride (TBTCl), are environmental contaminants that are commonly found in the antifouling paints used in ships and other vessels. The importance of TBTCl as an endocrine-disrupting chemical (EDC) in different animal models is well known; however, its adverse effects on the thyroid gland are less understood. Hence, in the present study, we aimed to evaluate the thyroid-disrupting effects of this chemical using both in vitro and in vivo approaches. We used HepG2 hepatocarcinoma cells for the in vitro studies, as they are a thyroid hormone receptor (TR)-positive and thyroid responsive cell line. For the in vivo studies, Swiss albino male mice were exposed to three doses of TBTCl (0.5, 5 and 50μg/kg/day) for 45days. TBTCl showed a hypo-thyroidal effect in vivo. Low-dose treatment of TBTCl exposure markedly decreased the serum thyroid hormone levels via the down-regulation of the thyroid peroxidase (TPO) and thyroglobulin (Tg) genes by 40% and 25%, respectively, while augmenting the thyroid stimulating hormone (TSH) levels. Thyroid-stimulating hormone receptor (TSHR) expression was up-regulated in the thyroid glands of treated mice by 6.6-fold relative to vehicle-treated mice (p<0.05). In the transient transactivation assays, TBTCl suppressed T3 mediated transcriptional activity in a dose-dependent manner. In addition, TBTCl was found to decrease the expression of TR. The present study thus indicates that low concentrations of TBTCl suppress TR transcription by disrupting the physiological concentrations of T3/T4, followed by the recruitment of NCoR to TR, providing a novel insight into the thyroid hormone-disrupting effects of this chemical.

  11. Disruption of thyroid hormone functions by low dose exposure of tributyltin: an in vitro and in vivo approach.

    PubMed

    Sharan, Shruti; Nikhil, Kumar; Roy, Partha

    2014-09-15

    Triorganotins, such as tributyltin chloride (TBTCl), are environmental contaminants that are commonly found in the antifouling paints used in ships and other vessels. The importance of TBTCl as an endocrine-disrupting chemical (EDC) in different animal models is well known; however, its adverse effects on the thyroid gland are less understood. Hence, in the present study, we aimed to evaluate the thyroid-disrupting effects of this chemical using both in vitro and in vivo approaches. We used HepG2 hepatocarcinoma cells for the in vitro studies, as they are a thyroid hormone receptor (TR)-positive and thyroid responsive cell line. For the in vivo studies, Swiss albino male mice were exposed to three doses of TBTCl (0.5, 5 and 50μg/kg/day) for 45days. TBTCl showed a hypo-thyroidal effect in vivo. Low-dose treatment of TBTCl exposure markedly decreased the serum thyroid hormone levels via the down-regulation of the thyroid peroxidase (TPO) and thyroglobulin (Tg) genes by 40% and 25%, respectively, while augmenting the thyroid stimulating hormone (TSH) levels. Thyroid-stimulating hormone receptor (TSHR) expression was up-regulated in the thyroid glands of treated mice by 6.6-fold relative to vehicle-treated mice (p<0.05). In the transient transactivation assays, TBTCl suppressed T3 mediated transcriptional activity in a dose-dependent manner. In addition, TBTCl was found to decrease the expression of TR. The present study thus indicates that low concentrations of TBTCl suppress TR transcription by disrupting the physiological concentrations of T3/T4, followed by the recruitment of NCoR to TR, providing a novel insight into the thyroid hormone-disrupting effects of this chemical. PMID:25101840

  12. Nanogold-polyaniline-nanogold microspheres-functionalized molecular tags for sensitive electrochemical immunoassay of thyroid-stimulating hormone.

    PubMed

    Cui, Yuling; Chen, Huafeng; Hou, Li; Zhang, Bing; Liu, Bingqian; Chen, Guonan; Tang, Dianping

    2012-08-13

    Methods based on nanomaterial labels have been developed for electrochemical immunosensors and immunoassays, but most involved low sensitivity. Herein a novel class of molecular tags, nanogold-polyaniline-nanogold microspheres (GPGs), was first synthesized and functionalized with horseradish peroxidase-conjugated thyroid-stimulating hormone antibody (HRP-Ab(2)) for sensitive electrochemical immunoassay of thyroid-stimulating hormone (TSH). X-ray diffraction, confocal Raman spectroscopy, scanning electron microscope and transmission electron microscope were employed to characterize the prepared GPGs. Based on a sandwich-type immunoassay format, the assay was performed in pH 5.0 acetate buffer containing 6.0mmolL(-1) H(2)O(2) by using GPG-labeled HRP-Ab(2) as molecular tags. Compared with pure polyaniline nanospheres and gold nanoparticles alone, the GPG hybrid nanostructures increased the surface area of the nanomaterials, and enhanced the immobilized amount of HRP-Ab(2). Several labeling protocols comprising HRP-Ab(2), nanogold particle-labeled HRP-Ab(2), and polyaniline nanospheres-labeled HRP-Ab(2), were also investigated for determination of TSH and improved analytical features were obtained by using the GPG-labeled HRP-Ab(2). With the GPG labeling method, the effects of incubation time and pH of acetate buffer on the current responses of the immunosensors were also studied. The strong attachment of HRP-Ab(2) to the GPGs resulted in a good repeatability and intermediate precision down to 7%. The dynamic concentration range spanned from 0.01 to 20μIUmL(-1) with a detection limit (LOD) of 0.005μIUmL(-1) TSH at the 3s(B) criterion. Significantly, no significant differences at the 0.05 significance level were encountered in the analysis of 15 spiking serum samples between the developed electrochemical immunoassay and the commercially available enzyme-linked immunosorbent assay (ELISA) method for determination of TSH.

  13. Peripheral blood lymphocyte apoptosis and its relationship with thyroid function tests in adolescents with hyperthyroidism due to Graves' disease

    PubMed Central

    Grywalska, Ewelina; Surdacka, Agata; Tarach, Jerzy; Klatka, Janusz; Roliński, Jacek

    2012-01-01

    Introduction Failures in apoptotic pathways can contribute to various autoimmune diseases, including autoimmune hyperthyroidism due to Graves’ disease (GD). The aim of the present research was to assess changes in the degree of peripheral blood (PB) lymphocyte apoptosis during methimazole (MMI) treatment in the group of teenage children, and to describe its relationship with thyroid function tests. Material and methods The percentage of PB apoptotic lymphocytes, assessed by the decrease in mitochondrial transmembrane potential (CMXRos staining), was measured in 30 adolescents at the time of diagnosis and after obtaining normalization of the thyroid hormone levels. Results The percentage of apoptotic lymphocytes in previously untreated patients with GD (5.16 ±2.81%) was significantly lower (p = 0.000001) than the percentage of apoptotic cells in the same group of patients after obtaining methimazole-induced euthyroidism (10.72 ±4.66%). There was a correlation between the increase of the mean percentages of apoptotic lymphocytes and the reduction of FT4 levels (R = 0.63, p < 0.0001), as well as the reduction of TT3 levels (R = 0.95, p < 0.0001). The more signs and symptoms accompanying the diagnosis of GD, the higher was the increment of the degree of lymphocyte apoptosis observed during the MMI-treatment (R = 0.74, p < 0.0000001). The methimazole dosage correlated (R = 0.85, p < 0.0001) with the percentage of apoptotic cells. Conclusions The use of methimazole in treatment of hyperthyroidism due to GD leads to an increment of apoptotic cells in PB. Higher doses of methimazole cause a higher increase of apoptotic lymphocytes. Apoptosis induction of human PB lymphocytes seems to be one of the indicators of proper hyperthyroidism treatment. PMID:23185197

  14. Thyroid disruption in zebrafish (Danio rerio) larvae: Different molecular response patterns lead to impaired eye development and visual functions.

    PubMed

    Baumann, Lisa; Ros, Albert; Rehberger, Kristina; Neuhauss, Stephan C F; Segner, Helmut

    2016-03-01

    The vertebrate thyroid system is important for multiple developmental processes, including eye development. Thus, its environmentally induced disruption may impact important fitness-related parameters like visual capacities and behaviour. The present study investigated the relation between molecular effects of thyroid disruption and morphological and physiological changes of eye development in zebrafish (Danio rerio). Two test compounds representing different molecular modes of thyroid disruption were used: propylthiouracil (PTU), which is an enzyme-inhibitor of thyroid hormone synthesis, and tetrabromobisphenol A (TBBPA), which interacts with the thyroid hormone receptors. Both chemicals significantly altered transcript levels of thyroid system-related genes (TRα, TRβ, TPO, TSH, DIO1, DIO2 and DIO3) in a compound-specific way. Despite these different molecular response patterns, both treatments resulted in similar pathological alterations of the eyes such as reduced size, RPE cell diameter and pigmentation, which were concentration-dependent. The morphological changes translated into impaired visual performance of the larvae: the optokinetic response was significantly and concentration-dependently decreased in both treatments, together with a significant increase of light preference of PTU-treated larvae. In addition, swimming activity was impacted. This study provides first evidence that different modes of molecular action of the thyroid disruptors can be associated with uniform apical responses. Furthermore, this study is the first to show that pathological eye development, as it can be induced by exposure to thyroid disruptors, indeed translates into impaired visual capacities of zebrafish early life stages.

  15. Thyroid disruption in zebrafish (Danio rerio) larvae: Different molecular response patterns lead to impaired eye development and visual functions.

    PubMed

    Baumann, Lisa; Ros, Albert; Rehberger, Kristina; Neuhauss, Stephan C F; Segner, Helmut

    2016-03-01

    The vertebrate thyroid system is important for multiple developmental processes, including eye development. Thus, its environmentally induced disruption may impact important fitness-related parameters like visual capacities and behaviour. The present study investigated the relation between molecular effects of thyroid disruption and morphological and physiological changes of eye development in zebrafish (Danio rerio). Two test compounds representing different molecular modes of thyroid disruption were used: propylthiouracil (PTU), which is an enzyme-inhibitor of thyroid hormone synthesis, and tetrabromobisphenol A (TBBPA), which interacts with the thyroid hormone receptors. Both chemicals significantly altered transcript levels of thyroid system-related genes (TRα, TRβ, TPO, TSH, DIO1, DIO2 and DIO3) in a compound-specific way. Despite these different molecular response patterns, both treatments resulted in similar pathological alterations of the eyes such as reduced size, RPE cell diameter and pigmentation, which were concentration-dependent. The morphological changes translated into impaired visual performance of the larvae: the optokinetic response was significantly and concentration-dependently decreased in both treatments, together with a significant increase of light preference of PTU-treated larvae. In addition, swimming activity was impacted. This study provides first evidence that different modes of molecular action of the thyroid disruptors can be associated with uniform apical responses. Furthermore, this study is the first to show that pathological eye development, as it can be induced by exposure to thyroid disruptors, indeed translates into impaired visual capacities of zebrafish early life stages. PMID:26765085

  16. Thyroxine treatment in patients with symptoms of hypothyroidism but thyroid function tests within the reference range: randomised double blind placebo controlled crossover trial

    PubMed Central

    Pollock, M Anne; Sturrock, Alison; Marshall, Karen; Davidson, Kate M; Kelly, Christopher J G; McMahon, Alex D; McLaren, E Hamish

    2001-01-01

    Objectives To determine whether thyroxine treatment is effective in patients with symptoms of hypothyroidism but with thyroid function tests within the reference range, and to investigate the effect of thyroxine treatment on psychological and physical wellbeing in healthy participants. Design Randomised double blind placebo controlled crossover trial. Setting Outpatient clinic in a general hospital. Participants 25 patients with symptoms of hypothyroidism who had thyroid function tests within the reference range, and 19 controls. Methods Participants were given thyroxine 100 μg or placebo to take once a day for 12 weeks. Washout period was six weeks. They were then given the other to take once a day for 12 weeks. All participants were assessed physiologically and psychologically at baseline and on completion of each phase. Main outcome measures Thyroid function tests, measures of cognitive function and of psychological and physical wellbeing. Results 22 patients and 19 healthy controls completed the study. At baseline, patients' scores on 9 out of 15 psychological measures were impaired when compared with controls. Patients showed a significantly greater response to placebo than controls in 3 out of 15 psychological measures. Healthy participants had significantly lower scores for vitality when taking thyroxine compared to placebo (mean (SD) 60 (17) v 73 (16), P<0.01). However, patients' scores from psychological tests when taking thyroxine were no different from those when taking placebo except for a poorer performance on one visual reproduction test when taking thyroxine. Serum concentrations of free thyroxine increased and those of thyroid stimulating hormone decreased in patients and controls while they were taking thyroxine, confirming compliance with treatment. Although serum concentrations of free triiodothyronine increased in patients and controls taking thyroxine, the difference between the response to placebo and to thyroxine was significant only in the

  17. Thyroid Function and its Implications in Oxidative Stress Influencing the Pathogenesis of Osteoporosis in Adults with Down Syndrome: A Cohort Study.

    PubMed

    Villani, E R; Onder, G; Carfì, A; Di Segni, C; Raimondo, S; Silvestrini, A; Meucci, E; Mancini, A

    2016-09-01

    People with Down syndrome (DS) show lower bone mass density (BMD) and a higher prevalence of hypothyroidism compared to general population. Furthermore, DS is a well-known high oxidative stress (OS) condition because genes involved in OS map on chromosome 21. Thyroid function too is involved in OS. Since both thyroid function and OS lead to lower BMD and osteoporotic fractures, we have explored correlations among BMD, thyroid hormones, and parameters of OS in DS adults. A total of 105 DS patients (48 males; 21-71 years; mean BMI 28.88±7.12 kg/m(2)) were enrolled in a cohort study, 48 of them undergoing thyroid replacement therapy. We evaluated thyroid function, BMD, and total antioxidant capacity (TAC) in blood plasma. TAC was assayed by H2O2-metmyoglobin system, as source of radicals, and by the chromogenous ABTS, with a latency time (LAG) in the appearance of its cation ABTS+proportional to antioxidant concentration. BMD was evaluated with DEXA, using WHO criteria to classify osteoporosis. Low BMD was found in 83.78% of patients. TSH and LAG did not correlate with BMD. Nevertheless, LAG significantly correlates to Z-scores estimated at the lumbar spine (r(2)=0.558; p=0.03) in hypothyroid patients. Our data show that low TAC could be more associated with reduced BMD rather than TSH itself in DS patients and that the OS could have a role in the pathogenesis of osteoporosis regarding the hypothyroid subgroup. PMID:27557341

  18. The histopathologic features of lithium-associated thyroiditis.

    PubMed

    Kontozoglou, T; Mambo, N

    1983-08-01

    The case of a 62-year-old woman with lithium-associated thyroiditis is presented. Lithium can produce goiters associated with hypothyroidism and, less commonly, hyperthyroidism and euthyroidism. The characteristic histopathologic features of the affected thyroid gland included fibrosis, lymphoid follicles with atrophy, and hyperplasia of thyroid follicles. The pathogenetic mechanism appears to be immunologic, with lithium acting as a haptene with a thyroid antigen to induce an "autoimmune" type of thyroiditis.

  19. Dietary contaminant exposure affects plasma testosterone, but not thyroid hormones, vitamin A, and vitamin E, in male juvenile arctic foxes (Vulpes lagopus).

    PubMed

    Hallanger, Ingeborg G; Jørgensen, Even H; Fuglei, Eva; Ahlstrøm, Øystein; Muir, Derek C G; Jenssen, Bjørn Munro

    2012-01-01

    Levels of persistent organic pollutants (POP), such as polychlorinated biphenyls (PCB), are high in many Arctic top predators, including the Arctic fox (Vulpes lagopus). The aim of this study was to examine possible endocrine-disruptive effects of dietary POP exposure in male juvenile Arctic foxes in a controlled exposure experiment. The study was conducted using domesticated farmed blue foxes (Vulpes lagopus) as a model species. Two groups of newly weaned male foxes received a diet supplemented with either minke whale (Baleneoptera acutorostrata) blubber that was naturally contaminated with POP (exposed group, n = 5 or 21), or pork (Sus scrofa) fat (control group, n = 5 or 21). When the foxes were 6 mo old and had received the 2 diets for approximately 4 mo (147 d), effects of the dietary exposure to POP on plasma concentrations of testosterone (T), thyroid hormones (TH), thyroid-stimulating hormone (TSH), retinol (vitamin A), and tocopherol (viramin E) were examined. At sampling, the total body concentrations of 104 PCB congeners were 0.1 ± 0.03 μg/g lipid weight (l.w.; n = 5 [mean ± standard deviation]) and 1.5 ± 0.17 μg/g l.w. (n = 5) in the control and exposed groups, respectively. Plasma testosterone concentrations in the exposed male foxes were significantly lower than in the control males, being approximately 25% of that in the exposed foxes. There were no between-treatment differences for TH, TSH, retinol, or tocopherol. The results suggest that the high POP levels experienced by costal populations of Arctic foxes, such as in Svalbard and Iceland, may result in delayed masculine maturation during adolescence. Sex hormone disruption during puberty may thus have lifetime consequences on all aspects of reproductive function in adult male foxes. PMID:23030655

  20. Thyroid doses for evacuees from the Fukushima nuclear accident

    NASA Astrophysics Data System (ADS)

    Tokonami, Shinji; Hosoda, Masahiro; Akiba, Suminori; Sorimachi, Atsuyuki; Kashiwakura, Ikuo; Balonov, Mikhail

    2012-07-01

    A primary health concern among residents and evacuees in affected areas immediately after a nuclear accident is the internal exposure of the thyroid to radioiodine, particularly I-131, and subsequent thyroid cancer risk. In Japan, the natural disasters of the earthquake and tsunami in March 2011 destroyed an important function of the Fukushima Daiichi Nuclear Power Plant (F1-NPP) and a large amount of radioactive material was released to the environment. Here we report for the first time extensive measurements of the exposure to I-131 revealing I-131 activity in the thyroid of 46 out of the 62 residents and evacuees measured. The median thyroid equivalent dose was estimated to be 4.2 mSv and 3.5 mSv for children and adults, respectively, much smaller than the mean thyroid dose in the Chernobyl accident (490 mSv in evacuees). Maximum thyroid doses for children and adults were 23 mSv and 33 mSv, respectively.

  1. Thyroid doses for evacuees from the Fukushima nuclear accident

    PubMed Central

    Tokonami, Shinji; Hosoda, Masahiro; Akiba, Suminori; Sorimachi, Atsuyuki; Kashiwakura, Ikuo; Balonov, Mikhail

    2012-01-01

    A primary health concern among residents and evacuees in affected areas immediately after a nuclear accident is the internal exposure of the thyroid to radioiodine, particularly I-131, and subsequent thyroid cancer risk. In Japan, the natural disasters of the earthquake and tsunami in March 2011 destroyed an important function of the Fukushima Daiichi Nuclear Power Plant (F1-NPP) and a large amount of radioactive material was released to the environment. Here we report for the first time extensive measurements of the exposure to I-131 revealing I-131 activity in the thyroid of 46 out of the 62 residents and evacuees measured. The median thyroid equivalent dose was estimated to be 4.2 mSv and 3.5 mSv for children and adults, respectively, much smaller than the mean thyroid dose in the Chernobyl accident (490 mSv in evacuees). Maximum thyroid doses for children and adults were 23 mSv and 33 mSv, respectively. PMID:22792439

  2. Thyroid Dysfunction as a Mediator of Organochlorine Neurotoxicity in Preschool Children

    PubMed Central

    Debes, Frodi; Weihe, Pal; Choi, Anna L.; Grandjean, Philippe

    2011-01-01

    Background: Exposure to organochlorine compounds (OCs) can alter thyroid function in humans, and hypothyroidism during early life can adversely affect a child’s neurodevelopment. Objectives: In this study we aimed to assess the relationship between developmental organochlorine exposures and thyroid function and the relationship between thyroid function and subsequent neurodevelopment. Methods: A population-based birth cohort of 182 children was followed annually up to 5.5 years of age. The assessments included OC concentrations in maternal pregnancy serum and milk, clinical thyroid parameters in maternal and cord serum, and subsequent neuropsychological outcomes of the child, along with sociodemographic cofactors. Resin triiodothyronine uptake ratio (T3RU) was also assessed as an estimate of the amount of thyroxine-binding globulin (TBG) sites unsaturated by thyroxine. The T3RU is high in hyperthyroidism and low in hypothyroidism. Results: The findings showed consistent inverse and monotonic associations between organochlorine exposure and T3RU after covariate adjustments. We observed no associations with other thyroid parameters. T3RU was positively associated with improved performance on most of the neuropsychological tests. For other thyroid parameters, the findings were less consistent. Conclusions: The results suggest that OC exposures may decrease the T3RU during early life, which is a proxy measure of the binding capacity of TBG. In addition, minor decreases of the thyroid function may be inversely associated with a child’s neurodevelopment. PMID:21719373

  3. Triple ectopic thyroid: A rare entity.

    PubMed

    Nilegaonkar, Sujit; Naik, Chetna; Sonar, Sameer; Hirawe, Deepti

    2011-10-01

    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.

  4. Effects of excessive intakes of iodine upon growth and thyroid function of growing Holstein heifers.

    PubMed

    Fish, R E; Swanson, E W

    1982-04-01

    Thirty Holstein heifer calves averaging 120 days of age and 102 kg of body weight were allocated to one control and four treatment groups of six each. Iodine, as ethylenediamine dihydriodide, was mixed 1:9 with dextrose and administered once daily atop feed at .625, 1.25, 2.5, or 5.0 mg iodine per kilogram body weight. Calves were housed individually in unheated, well-ventilated barns and fed complete mixed feeds containing less than 1 ppm iodine. Feed intakes were recorded daily and body weights weekly. Jugular venous blood was collected from iodine treated calves at 0, 4, 8, and 12 wk of the experiment and analyzed for iodine, thyroxine, and triiodothyronine of plasma. Feed intake per unit body weight and per unit gain were not significantly different between treated and control calves. However, daily feed intake and average daily gain decreased slightly at the highest iodine intake. Thyroxine and triiodothyronine were not different among treatments. Thyroxine declined in all calves from 0 to 12 wk. Thyroxine of calves fed 5.0 mg of iodine per kilogram body weight decreased more than of calves fed less iodine. Iodine intake as high as 5.0 mg/kg body weight was tolerated without morbidity, although a minor effect on performance and thyroid activity was indicated.

  5. Transient Hypothyroidism after Radioiodine for Graves’ Disease: Challenges in Interpreting Thyroid Function Tests

    PubMed Central

    Sheehan, Michael T.; Doi, Suhail A.R.

    2016-01-01

    Graves’ disease is the most common cause of hyperthyroidism and is often managed with radioactive iodine (RAI) therapy. With current dosing schemes, the vast majority of patients develop permanent post-RAI hypothyroidism and are placed on life-long levothyroxine therapy. This hypothyroidism typically occurs within the first 3 to 6 months after RAI therapy is administered. Indeed, patients are typically told to expect life-long thyroid hormone replacement therapy to be required within this timeframe and many providers expect this post-RAI hypothyroidism to be complete and permanent. There is, however, a small subset of patients in whom a transient post-RAI hypothyroidism develops which, initially, presents exactly as the typical permanent hypothyroidism. In some cases the transient hypothyroidism leads to a period of euthyroidism of variable duration eventually progressing to permanent hypothyroidism. In others, persistent hyperthyroidism requires a second dose of RAI. Failure to appreciate and recognize the possibility of transient post-RAI hypothyroidism can delay optimal and appropriate treatment of the patient. We herein describe five cases of transient post-RAI hypothyroidism which highlight this unusual sequence of events. Increased awareness of this possible outcome after RAI for Graves’ disease will help in the timely management of patients. PMID:26864507

  6. Transient Hypothyroidism after Radioiodine for Graves' Disease: Challenges in Interpreting Thyroid Function Tests.

    PubMed

    Sheehan, Michael T; Doi, Suhail A R

    2016-03-01

    Graves' disease is the most common cause of hyperthyroidism and is often managed with radioactive iodine (RAI) therapy. With current dosing schemes, the vast majority of patients develop permanent post-RAI hypothyroidism and are placed on life-long levothyroxine therapy. This hypothyroidism typically occurs within the first 3 to 6 months after RAI therapy is administered. Indeed, patients are typically told to expect life-long thyroid hormone replacement therapy to be required within this timeframe and many providers expect this post-RAI hypothyroidism to be complete and permanent. There is, however, a small subset of patients in whom a transient post-RAI hypothyroidism develops which, initially, presents exactly as the typical permanent hypothyroidism. In some cases the transient hypothyroidism leads to a period of euthyroidism of variable duration eventually progressing to permanent hypothyroidism. In others, persistent hyperthyroidism requires a second dose of RAI. Failure to appreciate and recognize the possibility of transient post-RAI hypothyroidism can delay optimal and appropriate treatment of the patient. We herein describe five cases of transient post-RAI hypothyroidism which highlight this unusual sequence of events. Increased awareness of this possible outcome after RAI for Graves' disease will help in the timely management of patients. PMID:26864507

  7. What Causes Thyroid Cancer?

    MedlinePlus

    ... not yet known. Certain changes in a person’s DNA can cause thyroid cells to become cancerous. DNA is the chemical in each of our cells ... parents because they are the source of our DNA. But DNA affects more than just how we ...

  8. Cognitive function in the affective disorders: a prospective study.

    PubMed

    Bulbena, A; Berrios, G E

    1993-01-01

    A prospective, controlled study of 50 subjects confirmed claims that major depression or mania may cause temporary disorders of attention, memory, visuo-spatial function, and choice reaction time, and cause-independently of medication-the appearance of glabellar tap, positive hand-face test, nuchocephalic reflex, and graphesthesia. On follow-up, all these phenomena either disappeared or markedly improved. Age and age of onset, but not pre-morbid intelligence or history of ECT, seemed to modulate the severity of the cognitive impairment. Presence of delusions predicted poor (but reversible) visuo-spatial function. Cognitive impairment accompanied by reversible soft neurological signs was more marked but patients thus affected surprisingly showed lower depressive scores; this was interpreted as representing a secondary, 'organic' form of affective disorder (i.e. a behavioural phenocopy of depression) characterised by a reduced capacity to experience depressive symptoms and by little improvement at follow-up.

  9. SU-E-I-24: Design and Fabrication of a Multi-Functional Neck and Thyroid Phantom for Medical Dosimetry and Calibration

    SciTech Connect

    Mehdizadeh, S; Sina, S; Karimipourfard, M; Lotfalizadeh, F; Faghihi, R; Babaei, A

    2014-06-01

    Purpose: The purpose of this study is the design and fabrication of a multipurpose anthropomorphic neck and thyroid phantom for use in medical applications (i.e. quality control of images in nuclear medicine, and dosimetry). Methods: The designed neck phantom is composed of seven elliptic cylindrical slices with semi-major axis of 14 and semi-minor axis of 12.5 cm, each having the thickness of 2cm. Thyroid gland, bony part of the neck, and the wind pipe were also built inside the neck phantom. Results: The phantom contains some removable plugs,inside and at its surface to accommodate the TLD chips with different shapes and dimensions, (i.e. rod, cylindrical and cubical TLD chips)for the purpose of medical dosimetry (i.e. in radiology, radiotherapy, and nuclear medicine). For the purpose of quality control of images in nuclear medicine, the removable thyroid gland was built to accommodate the radioactive iodine. The female and male thyroid glands were built in two sizes separately. Conclusion: The designed phantom is a multi-functional phantom which is applicable for dosimetry in diagnostic radiology, radiotherapy, and quality control of images in nuclear medicine.

  10. Evaluation of possible goitrogenic and anti-thyroidal effect of nitrate, a potential environmental pollutant.

    PubMed

    Mukhopadhyay, Sanjukta; Ghosh, Dishari; Chatterjee, Aparajita; Sinha, Sanchari; Tripathy, Smritiratan; Chandra, Amar K

    2005-01-01

    Nitrate is a wide spread contaminant of ground and surface water. The source of nitrate in the ground water may be from run off or seepage from fertilized soil, municipal or industrial waste water, land fills, septic system, urban drainage or decaying plants. Human and animal systems are affected severely on nitrate exposure. The study was to investigate the effect of dietary nitrate exposure on the thyroid status along with the state of iodine nutrition. Rats were fed diet containing 3% potassium nitrate (KNO3) for 4 weeks and then thyroid status was evaluated by thyroid gland weight, urinary iodine excretion pattern, thyroid peroxidase (TPO) activity, serum levels of total thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) concentrations. In nitrate treated animals, the weight of thyroid gland was increased significantly (P<0.001) while thyroid peroxidase activity (P<0.01), serum T4 (P<0.01) and serum T3 levels (P<0.001) were reduced; but serum TSH level was increased (P<0.001) along with slightly elevated iodine excretion level (P<0.001) in comparison to control animals. The overall results indicated the development of a relative state of functional hypothyroidism with enlarged thyroid after nitrate exposure. This study can explain a part for the persistence of residual goitre in the post-salt iodization phase.

  11. [Thyroid gland and fertility].

    PubMed

    Andreeva, P

    2014-01-01

    It is well-known that the thyroid hormones are associated with a number of aspects of the human reproduction. Both states, hyperthyroidism and hypothyroidism, have significant effect on the estrogen and androgen metabolism, the menstrual function and on fertility. The role of thyroid hormones (TH) during infertility has been little exploited. Interesting facts are that TH deficiency is more common in women with polycystic ovary syndrome (PCOS) and in certain cases with unexplained infertility. There are very few studies on the effect and paracrine regulation of TH and its receptors in the female reproductive tract. This report provides an overview of the most common thyroid disorders and their impact on ovarian function and reproductive performance in women as well as in cases with infertility and the implementation of assisted reproductive technologies (ART). PMID:25675618

  12. Actions of Thyroid Hormone Analogues on Chemokines.

    PubMed

    Davis, Paul J; Glinsky, Gennadi V; Lin, Hung-Yun; Mousa, Shaker A

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3'-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  13. Actions of Thyroid Hormone Analogues on Chemokines

    PubMed Central

    Glinsky, Gennadi V.

    2016-01-01

    The extracellular domain of plasma membrane integrin αvβ3 contains a receptor for thyroid hormone (L-thyroxine, T4; 3,5,3′-triiodo-L-thyronine, T3); this receptor also binds tetraiodothyroacetic acid (tetrac), a derivative of T4. Tetrac inhibits the binding of T4 and T3 to the integrin. Fractalkine (CX3CL1) is a chemokine relevant to inflammatory processes in the CNS that are microglia-dependent but also important to normal brain development. Expression of the CX3CL1 gene is downregulated by tetrac, suggesting that T4 and T3 may stimulate fractalkine expression. Independently of its specific receptor (CX3CR1), fractalkine binds to αvβ3 at a site proximal to the thyroid hormone-tetrac receptor and changes the physical state of the integrin. Tetrac also affects expression of the genes for other CNS-relevant chemokines, including CCL20, CCL26, CXCL2, CXCL3, and CXCL10. The chemokine products of these genes are important to vascularity of the brain, particularly of the choroid plexus, to inflammatory processes in the CNS and, in certain cases, to neuroprotection. Thyroid hormones are known to contribute to regulation of each of these CNS functions. We propose that actions of thyroid hormone and hormone analogues on chemokine gene expression contribute to regulation of inflammatory processes in brain and of brain blood vessel formation and maintenance. PMID:27493972

  14. Male reproductive hormones and thyroid function in pesticide applicators in the Red River Valley of Minnesota.

    PubMed

    Garry, Vincent F; Holland, Seth E; Erickson, Leanna L; Burroughs, Barbara L

    2003-06-13

    In the present effort, 144 pesticide applicators and 49 urban control subjects who reported no chronic disease were studied. Applicators provided records of the season's pesticides used by product, volumes, dates, and methods of application. Blood specimens for examination of hormone levels were obtained in summer and fall. In the herbicide-only applicator group, significant increases in testosterone levels in fall compared to summer and also elevated levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in the fall were noted. With respect to fungicide use, in an earlier cross-sectional epidemiologic study, data demonstrated that historic fungicide use was associated with a significant alteration of the sex ratio of children borne to applicators. As before, among current study subjects it was noted that historic fungicide use was associated with increased numbers of girls being born. Lower mean total testosterone concentrations by quartile were also correlated with increased numbers of live-born female infants. A downward summer to fall seasonal shift in thyroid-stimulating hormone (TSH) concentrations occurred among applicators but not among controls. Farmers who had aerial application of fungicides to their land in the current season showed a significant shift in TSH values (from 1.75 to 1.11 mU/L). Subclinical hypothyroidism was noted in 5/144 applicators (TSH values >4.5 mU/L), but not in urban control subjects. Based on current and past studies, it was concluded that, in addition to pesticide exposure, individual susceptibility and perhaps economic factors may play a supporting role in the reported results.

  15. Thyroid gland function during cross adaptation to heat and cold in man

    NASA Astrophysics Data System (ADS)

    Sridharan, K.; Sawhney, R. C.; Mathew, L.; Pichan, G.; Malhotra, A. S.

    1986-09-01

    Plasma thyroxine (T4), triiodothyronine (T3) and thyrotropin (TSH) levels were monitored in 10 healthy euthyroid male subjects of the age group 20 to 30 years before and during heat and cold acclimatisation schedule in a sequential manner. The subjects were exposed to 45‡C DB and 30% relative humidity in a hot chamber for 2 hours daily for 8 consecutive days. Subsequently they were exposed to cold for 4 hours daily at 10‡C for 21 days. The mean plasma T4 and T3 concentration before exposure to heat were 7.87±0.82 ug/dl and 159.8±9.1 ng/dl respectively. A significant decrease in both T4 (p<0.05) and T3 (p<0.01) levels to mean values of 6.4±0.76 Μg/dl and 129±7.9 ng/dl was recorded on day 4 of exposure to heat. Further significant decrease (p<0.05) over the preceding T3 levels was observed on day 8 of heat exposure. Plasma T4 and T3 on day 21 of cold exposure was not significantly different from the levels reckoned after last day of heat exposure but was significantly lower than the pre-exposure values. Throughout the thermal stress schedule there was no change in the TSH levels. These observations suggest that a decrease in thyroid hormone levels during exposure to heat might be an adaptive process which continues even during cold acclimatisation.

  16. Thyroid: biological actions of 'nonclassical' thyroid hormones.

    PubMed

    Senese, Rosalba; Cioffi, Federica; de Lange, Pieter; Goglia, Fernando; Lanni, Antonia

    2014-05-01

    Thyroid hormones (THs) are produced by the thyroid gland and converted in peripheral organs by deiodinases. THs regulate cell functions through two distinct mechanisms: genomic (nuclear) and nongenomic (non-nuclear). Many TH effects are mediated by the genomic pathway--a mechanism that requires TH activation of nuclear thyroid hormone receptors. The overall nongenomic processes, emerging as important accessory mechanisms in TH actions, have been observed at the plasma membrane, in the cytoplasm and cytoskeleton, and in organelles. Some products of peripheral TH metabolism (besides triiodo-L-thyronine), now termed 'nonclassical THs', were previously considered as inactive breakdown products. However, several reports have recently shown that they may have relevant biological effects. The recent accumulation of knowledge on how classical and nonclassical THs modulate the activity of membrane receptors, components of the mitochondrial respiratory chain, kinases and deacetylases, opened the door to the discovery of new pathways through which they act. We reviewed the current state-of-the-art on the actions of the nonclassical THs, discussing the role that these endogenous TH metabolites may have in the modulation of thyroid-related effects in organisms with differing complexity, ranging from nonmammals to humans.

  17. Thyroid cancer - medullary carcinoma

    MedlinePlus

    Thyroid - medullary carcinoma; Cancer - thyroid (medullary carcinoma); MTC; Thyroid nodule - medullary ... The cause of medullary carcinoma of the thyroid (MTC) is unknown. MTC is very rare. It can occur in children and adults. Unlike other types ...

  18. Hashimoto's thyroiditis and papillary carcinoma in an adolescent girl: A case report

    PubMed Central

    DONG, LI-QUN; SUN, XIAO-MEI; XIANG, CHENG-FA; WU, JIN; YU, PING

    2016-01-01

    Hashimoto's thyroiditis with thyroid cancer in childhood is not as common in the adult population. Hashimoto's thyroiditis is an autoimmune disease associated with autoantibodies, and the association between Hashimoto's thyroiditis and papillary carcinoma of the thyroid remains controversial. The present study reported a 15-year-old adolescent girl with the diagnosis of Hashimoto's thyroiditis with thyroid cancer. With the complexity of the clinical manifestations of Hashimoto's thyroiditis, it can be expressed as not only hyperthyroidism or hypothyroidism, but also normal thyroid function. The long-term treatment, and for children with thyroid cancer, early diagnosis is particularly difficult. In the present case, the diagnosis of Hashimoto's thyroiditis is primarily based on clinical manifestations, anti-thyroglobulin antibody and anti-thyroid microsomal antibody. The only diagnostic imaging ultrasound was negative. The present study discussed the possible reason and the identification of this unique case of Hashimoto's thyroiditis with thyroid cancer. PMID:27330783

  19. Thyroid hormone is required for pruning, functioning and long-term maintenance of afferent inner hair cell synapses.

    PubMed

    Sundaresan, Srividya; Kong, Jee-Hyun; Fang, Qing; Salles, Felipe T; Wangsawihardja, Felix; Ricci, Anthony J; Mustapha, Mirna

    2016-01-01

    Functional maturation of afferent synaptic connections to inner hair cells (IHCs) involves pruning of excess synapses formed during development, as well as the strengthening and survival of the retained synapses. These events take place during the thyroid hormone (TH)-critical period of cochlear development, which is in the perinatal period for mice and in the third trimester for humans. Here, we used the hypothyroid Snell dwarf mouse (Pit1(dw)) as a model to study the role of TH in afferent type I synaptic refinement and functional maturation. We observed defects in afferent synaptic pruning and delays in calcium channel clustering in the IHCs of Pit1(dw) mice. Nevertheless, calcium currents and capacitance reached near normal levels in Pit1(dw) IHCs by the age of onset of hearing, despite the excess number of retained synapses. We restored normal synaptic pruning in Pit1(dw) IHCs by supplementing with TH from postnatal day (P)3 to P8, establishing this window as being critical for TH action on this process. Afferent terminals of older Pit1(dw) IHCs showed evidence of excitotoxic damage accompanied by a concomitant reduction in the levels of the glial glutamate transporter, GLAST. Our results indicate that a lack of TH during a critical period of inner ear development causes defects in pruning and long-term homeostatic maintenance of afferent synapses.

  20. Thyroid hormone is required for pruning, functioning and long-term maintenance of afferent inner hair cell synapses

    PubMed Central

    Sundaresan, Srividya; Kong, Jee-Hyun; Fang, Qing; Salles, Felipe T.; Wangsawihardja, Felix; Ricci, Anthony J.; Mustapha, Mirna

    2016-01-01

    Functional maturation of afferent synaptic connections to inner hair cells (IHCs) involves pruning of excess synapses formed during development, as well as the strengthening and survival of the retained synapses. These events take place during the thyroid hormone (TH)-critical period of cochlear development, which is in the perinatal period for mice and in the third trimester for humans. Here, we used the hypothyroid Snell dwarf mouse (Pit1dw) as a model to study the role of TH in afferent type I synaptic refinement and functional maturation. We observed defects in afferent synaptic pruning and delays in calcium channel clustering in the IHCs of Pit1dw mice. Nevertheless, calcium currents and capacitance reached near normal levels in Pit1dw IHCs by the age of onset of hearing, despite the excess number of retained synapses. We restored normal synaptic pruning in Pit1dw IHCs by supplementing with TH from postnatal day (P)3 to P8, establishing this window as being critical for TH action on this process. Afferent terminals of older Pit1dw IHCs showed evidence of excitotoxic damage accompanied by a concomitant reduction in the levels of the glial glutamate transporter, GLAST. Our results indicate that a lack of TH during a critical period of inner ear development causes defects in pruning and long-term homeostatic maintenance of afferent synapses. PMID:26386265

  1. Functional evaluation of TERT-CLPTM1L genetic variants associated with susceptibility of papillary thyroid carcinoma

    PubMed Central

    Ge, Minghua; Shi, Meng; An, Changming; Yang, Wenjun; Nie, Xilin; Zhang, Jian; Lv, Zheng; Li, Jinliang; Zhou, Liqing; Du, Zhongli; Yang, Ming

    2016-01-01

    TERT is the catalytic subunit of telomerase which plays an essential part in cellular immortality by maintaining telomere integrity. TERT is commonly over-expressed in human malignancies, indicating its key role in cell transformation. The chromosome 5p15.33 TERT-CLPTM1L region has been associated with susceptibility of multiple cancers via a genome-wide association approach. However, the involvement of this locus in papillary thyroid carcinoma (PTC) etiology is still largely unknown. We analyzed 15 haplotype-tagging single nucleotide polymorphisms (htSNPs) of the TERT-CLPTM1L region in a two stage case-control design. After genotyping 2300 PTC patients and frequency-matched 2300 unaffected controls, we found that TERT rs2736100 genetic variant is significantly associated with elevated PTC risk. Ex vivo reporter gene assays indicated that the PTC susceptibility rs2736100 polymorphism locating in a potential TERT intronic enhancer has a genotype-specific effect on TERT expression. Correlations between rs2736100 genotypes and tissue-specific TERT expression supported the regulatory function of this genetic variant in vivo. Our data demonstrated that the functional TERT rs2736100 SNP as a novel genetic component of PTC etiology. This study, together with recent studies in other cancers, unequivocally establishes an essential role of TERT in cancers. PMID:27185198

  2. Thyroid gland removal

    MedlinePlus

    Total thyroidectomy; Partial thyroidectomy; Thyroidectomy; Subtotal thyroidectomy; Thyroid cancer - thyroidectomy; Papillary cancer - thyroidectomy; Goiter - thyroidectomy; Thyroid nodules - thyroidectomy

  3. Thyroid cancer

    MedlinePlus

    ... cancer Laryngoscopy (looking inside the throat using a mirror or flexible tube called a laryngoscope placed through ... It may be performed by: Aiming external beam (x-ray) radiation at the thyroid Taking radioactive iodine by ...

  4. Ultrasound image of the thyroid gland in obese children

    PubMed Central

    Kosiak, Wojciech; Korpal-Szczyrska, Maria; Myśliwiec, Małgorzata

    2015-01-01

    Obesity as a disease of affluence also affects younger children. Numerous observations suggest a link between excessive body weight and thyroid function disorders. Subclinical hypothyroidism has been diagnosed increasingly frequently in patients with obesity. A growing number of papers also point to morphological changes of the thyroid gland in the ultrasound examination in obese children. These reports mainly concern changes in echogenicity. The present paper discusses the most important aspects of this topic on the basis of the literature as well as containing a brief analysis based on own experiences. PMID:26807299

  5. Factors affecting sexual function in menopause: A review article.

    PubMed

    Nazarpour, Soheila; Simbar, Masoumeh; Tehrani, Fahimeh Ramezani

    2016-08-01

    This study aimed to systematically review the articles on factors affecting sexual function during menopause. Searching articles indexed in Pubmed, Science Direct, Iranmedex, EMBASE, Scopus, and Scientific Information Database databases, a total number of 42 studies published between 2003 and 2013 were selected. Age, estrogen deficiency, type of menopause, chronic medical problems, partner's sex problems, severity of menopause symptoms, dystocia history, and health status were the physical factors influencing sexual function of menopausal women. There were conflicting results regarding the amount of androgens, hormonal therapy, exercise/physical activity, and obstetric history. In the mental-emotional area, all studies confirmed the impact of depression and anxiety. Social factors, including smoking, alcohol consumption, the quality of relationship with husband, partner's loyalty, sexual knowledge, access to health care, a history of divorce or the death of a husband, living apart from a spouse, and a negative understanding of women's health were found to affect sexual function; however, there were conflicting results regarding the effects of education, occupation, socioeconomic status, marital duration, and frequency of sexual intercourse. PMID:27590367

  6. Microbial composition affects the functioning of estuarine sediments

    PubMed Central

    Reed, Heather E; Martiny, Jennifer BH

    2013-01-01

    Although microorganisms largely drive many ecosystem processes, the relationship between microbial composition and their functioning remains unclear. To tease apart the effects of composition and the environment directly, microbial composition must be manipulated and maintained, ideally in a natural ecosystem. In this study, we aimed to test whether variability in microbial composition affects functional processes in a field setting, by reciprocally transplanting riverbed sediments between low- and high-salinity locations along the Nonesuch River (Maine, USA). We placed the sediments into microbial ‘cages' to prevent the migration of microorganisms, while allowing the sediments to experience the abiotic conditions of the surroundings. We performed two experiments, short- (1 week) and long-term (7 weeks) reciprocal transplants, after which we assayed a variety of functional processes in the cages. In both experiments, we examined the composition of bacteria generally (targeting the 16S rDNA gene) and sulfate-reducing bacteria (SRB) specifically (targeting the dsrAB gene) using terminal restriction fragment length polymorphism (T-RFLP). In the short-term experiment, sediment processes (CO2 production, CH4 flux, nitrification and enzyme activities) depended on both the sediment's origin (reflecting differences in microbial composition between salt and freshwater sediments) and the surrounding environment. In the long-term experiment, general bacterial composition (but not SRB composition) shifted in response to their new environment, and this composition was significantly correlated with sediment functioning. Further, sediment origin had a diminished effect, relative to the short-term experiment, on sediment processes. Overall, this study provides direct evidence that microbial composition directly affects functional processes in these sediments. PMID:23235294

  7. Metabolic alterations induced by chronic heat exposure in the rat: the involvement of thyroid function.

    PubMed

    Rousset, B; Cure, M; Jordan, D; Kervran, A; Bornet, H; Mornex, R

    1984-05-01

    The effects of chronic exposure to high environmental temperature (34 degrees C) on T4 production rate, food-intake, growth-rate and resting metabolic rate were investigated in adult male rats. This study was designed to examine the extent of variations and possible relationships between these parameters. As compared to control rats of the same body weight kept at 25 degrees C, rats exposed to 34 degrees C for 3-4 weeks exhibited a retarded growth-rate: 2.3 vs 4.0 g/day, a reduced food-intake: 15.2 vs 23.2 g/day, a decreased T4 production-rate: 1.8 vs 2.7 micrograms/day and a decreased oxygen consumption: 4.0 vs 5.4 ml/min. Heat-exposure altered the 4 parameters to a similar extent. T4 supplementation (3 micrograms/day) which induced a decrease in plasma TSH concentration, did not restore a normal growth-rate in heat-exposed rats. The decreased food-intake of the heat-exposed rats was not associated with any significant changes in the daily pattern of variations of liver glycogen content, or in the mean daily levels of blood glucose or insulin. The ratio T3 to rT3 in plasma was not altered by chronic heat exposure. When rats which had been chronically exposed to heat (25 days at 34 degrees C) were exposed to 25 degrees C, growth-rate, food-intake and oxygen consumption rapidly increased to control values whereas the rate of T4 production remained low. It is concluded that (1) a decrease in thyroid hormone economy is not directly involved in the alterations of growth and energy expenditure in rats chronically exposed to heat, (2) heat exposure does not lead to the establishment of a fasted state resulting from a large reduction in voluntary food intake, (3) metabolic alterations induced by heat exposure are rapidly and completely reversible upon decreasing the environmental temperature.

  8. Mode of action: developmental thyroid hormone insufficiency--neurological abnormalities resulting from exposure to propylthiouracil.

    PubMed

    Zoeller, R Thomas; Crofton, Kevin M

    2005-01-01

    Because thyroid hormone is essential for normal brain development before and after birth, environmental chemicals that interfere with thyroid hormone signaling can adversely affect brain development. Adverse consequences of thyroid hormone insufficiency depend both on severity and developmental timing, indicating that environmental antithyroid factors may produce different effects at different developmental windows of exposure. Mechanistic studies can provide important insight into the potential impact of chemicals on human thyroid function, but relevance to humans must be systematically evaluated. This kind of analysis depends on data sets that include information about animals and humans. The drug 6-n-propyl-2-thiouracil (PTU) is used in animals to experimentally manipulate serum thyroid hormone levels, and in humans to treat patients, including pregnant women, with Graves' disease. A systematic analysis of the mode of action (MOA) of PTU in rats and in humans discloses similar modes of action. While the analysis predicts that PTU doses that produce thyroid hormone insufficiency in humans would adversely affect the developing brain, careful monitoring of PTU administration in pregnant and lactating humans keeps infant serum thyroid hormone levels within the normal range.

  9. Perchlorate, iodine and the thyroid

    PubMed Central

    Leung, Angela M.; Pearce, Elizabeth N.; Braverman, Lewis E.

    2014-01-01

    In pharmacologic doses, perchlorate inhibits thyroidal iodine uptake and subsequently decreases thyroid hormone production. Although pharmacologic doses may be used in the treatment of hyperthyroidism, recent literature has focussed on the detection of low levels of perchlorate in the environment, groundwater and foodstuffs and their potential adverse effects on human thyroid function. This is of particular concern to the developing foetus and infant, whose normal neurodevelopment depends on adequate iodine intake for the production of thyroid hormones. Further research is needed to clarify the potential health effects of low-level chronic environmental perchlorate exposure. The health impact of environmental perchlorate may be dependent upon adequate iodine intake and should be interpreted in combination with other environmental exposures that are also potential thyroidal endocrine disruptors. PMID:20172477

  10. 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...

  11. Thyroid active agents T3 and PTU differentially affect immune gene transcripts in the head kidney of rainbow trout (Oncorynchus mykiss).

    PubMed

    Quesada-García, Alba; Encinas, Paloma; Valdehita, Ana; Baumann, Lisa; Segner, Helmut; Coll, Julio M; Navas, José M

    2016-05-01

    In mammals, numerous reports describe an immunomodulating effect of thyroid-active compounds. In contrast, only few reports have been published on this subject in fish. We previously demonstrated that immune cells of rainbow trout (Oncorhynchus mykiss) possess thyroid hormone receptors (THRs) and that exposure of trout to the thyroid hormone 3,3',5-triiodo-l-thyronine (T3) or the antithyroid drug propylthiouracil (PTU) alters immune cell transcript levels of THR and several immune genes. The present study aims to further characterize the immunomodulating action of thyroid-active compounds in trout immune cells. We report here the use of a custom-designed 60-mer oligo immune-targeted microarray for rainbow trout to analyze the gene expression profiles induced in the head kidney by T3 and PTU. Morphometric analyses of the thyroid showed that PTU exposure increased the size of the epithelial cells, whereas T3 induced no significant effects. Both T3 and PTU had diverse and partly contrasting effects on immune transcript profiles. The strongest differential effects of T3 and PTU on gene expressions were those targeting the Mitogen Associated Protein Kinase (MAPK), NFkB, Natural Killer (NK) and Toll-Like Receptor (TLR) pathways, a number of multipath genes (MPG) such as those encoding pleiotropic transcription factors (atf1, junb, myc), as well as important pro-inflammatory genes (tnfa, tnf6, il1b) and interferon-related genes (ifng, irf10). With these results we show for the first time in a fish species that the in vivo thyroidal status modulates a diversity of immune genes and pathways. This knowledge provides the basis to investigate both mechanisms and consequences of thyroid hormone- and thyroid disruptor-mediated immunomodulation for the immunocompetence of fish. PMID:26963519

  12. Thyroid active agents T3 and PTU differentially affect immune gene transcripts in the head kidney of rainbow trout (Oncorynchus mykiss).

    PubMed

    Quesada-García, Alba; Encinas, Paloma; Valdehita, Ana; Baumann, Lisa; Segner, Helmut; Coll, Julio M; Navas, José M

    2016-05-01

    In mammals, numerous reports describe an immunomodulating effect of thyroid-active compounds. In contrast, only few reports have been published on this subject in fish. We previously demonstrated that immune cells of rainbow trout (Oncorhynchus mykiss) possess thyroid hormone receptors (THRs) and that exposure of trout to the thyroid hormone 3,3',5-triiodo-l-thyronine (T3) or the antithyroid drug propylthiouracil (PTU) alters immune cell transcript levels of THR and several immune genes. The present study aims to further characterize the immunomodulating action of thyroid-active compounds in trout immune cells. We report here the use of a custom-designed 60-mer oligo immune-targeted microarray for rainbow trout to analyze the gene expression profiles induced in the head kidney by T3 and PTU. Morphometric analyses of the thyroid showed that PTU exposure increased the size of the epithelial cells, whereas T3 induced no significant effects. Both T3 and PTU had diverse and partly contrasting effects on immune transcript profiles. The strongest differential effects of T3 and PTU on gene expressions were those targeting the Mitogen Associated Protein Kinase (MAPK), NFkB, Natural Killer (NK) and Toll-Like Receptor (TLR) pathways, a number of multipath genes (MPG) such as those encoding pleiotropic transcription factors (atf1, junb, myc), as well as important pro-inflammatory genes (tnfa, tnf6, il1b) and interferon-related genes (ifng, irf10). With these results we show for the first time in a fish species that the in vivo thyroidal status modulates a diversity of immune genes and pathways. This knowledge provides the basis to investigate both mechanisms and consequences of thyroid hormone- and thyroid disruptor-mediated immunomodulation for the immunocompetence of fish.

  13. New Insights toward the Acute Non-Thyroidal Illness Syndrome.

    PubMed

    Wajner, Simone Magagnin; Maia, Ana Luiza

    2012-01-01

    The non-thyroidal illness syndrome (NTIS) refers to changes in serum thyroid hormone levels observed in critically ill patients in the absence of hypothalamic-pituitary-thyroid primary dysfunction. Affected individuals have low T3, elevated rT3, and inappropriately normal TSH levels. The pathophysiological mechanisms are poorly understood but the acute and chronic changes in pituitary-thyroid function are probably the consequence of the action of multiple factors. The early phase seems to reflect changes occurring primarily in the peripheral thyroid hormone metabolism, best seen in humans since 80-90% of the circulating T3 are derived from the pro-hormone T4. The conversion of T4 to T3 is catalyzed by type 1 (D1) and type 2 (D2) deiodinases via outer-ring deiodination. In contrast, type 3 deiodinase (D3) catalyzes the inactivation of both T4 and T3. Over the last decades, several studies have attempted to elucidate the mechanisms underlying the changes on circulating thyroid hormones in NTIS. Increased inflammatory cytokines, which occurs in response to virtually any illness, has long been speculated to play a role in derangements of deiodinase expression. On the other hand, oxidative stress due to augmented reactive oxygen species (ROS) generation is characteristic of many diseases that are associated with NTIS. Changes in the intracellular redox state may disrupt deiodinase function by independent mechanisms, which might include depletion of the as yet unidentified endogenous thiol cofactor. Here we aim to present an updated picture of the advances in understanding the mechanisms that result in the fall of thyroid hormone levels in the acute phase of NTIS.

  14. Polybrominated diphenyl ethers (PBDEs), hydroxylated PBDEs (OH-PBDEs), and measures of thyroid function in second trimester pregnant women in California

    PubMed Central

    Zota, Ami R.; Park, June-Soo; Wang, Yunzhu; Petreas, Myrto; Zoeller, R. Thomas; Woodruff, Tracey J.

    2011-01-01

    Prenatal exposure to polybrominated diphenyl ethers (PBDEs) may disrupt thyroid function and contribute to adverse neurodevelopmental outcomes. We conducted a pilot study to explore the relationship between serum concentrations of lower-brominated PBDEs (BDE-17 to -154), higher-brominated PBDEs (BDE-183 to -209), and hydroxylated PBDE metabolites (OH-PBDEs) with measures of thyroid function in pregnant women. Concentrations of PBDEs, OH-PBDEs, thyroid-stimulating hormone (TSH), total thyroxine (T4), and free T4 were measured in serum samples collected between 2008 and 2009 from 25 second trimester pregnant women in California. Median concentrations of lower-brominated PBDEs and OH-PBDEs were the highest reported to date in pregnant women. Median concentrations of BDE-47 and the sum of lower-brominated PBDEs (ΣPBDE5) were 43.1 ng/g lipid and 85.8 ng/g lipid; and 0.084 ng/mL for the sum of OH-PBDEs (ΣOH-PBDE4). We observed a positive association between the weighted sum of chemicals known to bind to transthyretin (ΣTTR binders) and TSH levels. We also found positive associations between TSH and ΣPBDE5, ΣOH-PBDE4, BDE-47, BDE-85, 5-OH-BDE47, and 4′-OH-BDE49; and an inverse association with BDE-207. Relationships with free and total T4 were weak and inconsistent. Our results indicate that PBDE exposures are elevated in pregnant women in California, and suggest a relationship with thyroid function. Further investigation is warranted to characterize the risks of PBDE exposures during pregnancy. PMID:21830753

  15. Catecholamines and myocardial contractile function during hypodynamia and with an altered thyroid hormone balance

    NASA Technical Reports Server (NTRS)

    Pruss, G. M.; Kuznetsov, V. I.; Zhilinskaya, A. A.

    1980-01-01

    The dynamics of catecholamine content and myocardial contractile function during hypodynamia were studied in 109 white rats whose motor activity was severely restricted for up to 30 days. During the first five days myocardial catecholamine content, contractile function, and physical load tolerance decreased. Small doses of thyroidin counteracted this tendency. After 15 days, noradrenalin content and other indices approached normal levels and, after 30 days, were the same as control levels, although cardiac functional reserve was decreased. Thyroidin administration after 15 days had no noticeable effect. A detailed table shows changes in 17 indices of myocardial contractile function during hypodynamia.

  16. A rare case of thyroid storm.

    PubMed

    McMillen, Brock; Dhillon, Manvinder Shelley; Yong-Yow, Sabrina

    2016-04-18

    Thyroid storm is a rare and life-threatening state of thyroid hormone excess. Rapid recognition of thyroid storm is key to decreasing the morbidity and mortality of this condition. Clinical manifestations of thyroid storm include unexplained weight loss, hyperactivity and irritability. The most common causes of thyrotoxicosis are Graves' disease, toxic multinodular goitre and toxic adenoma. We present a rare case of thyroid storm induced by dual nivolumab and ipilimumab immunotherapy in a patient receiving treatment for advanced melanoma. In this case, our patient was admitted for thyroid storm 1 month after initiating treatment with nivolumab and ipilimumab immunotherapy. The patient was treated with β-blockers, antithyroid medications and systemic steroids resulting in an improvement in thyroid function testing and symptoms.

  17. Nivolumab-induced thyroid dysfunction.

    PubMed

    Tanaka, Ryota; Fujisawa, Yasuhiro; Maruyama, Hiroshi; Nakamura, Yasuhiro; Yoshino, Koji; Ohtsuka, Mikio; Fujimoto, Manabu

    2016-06-01

    Nivolumab (ONO-4538) is an anti-programmed death-1 specific monoclonal antibody, which has become a standard treatment for metastatic malignant melanoma. Nivolumab induces autoimmune adverse events, defined as immune-related adverse events. Herein, we report a case of nivolumab-induced thyroid dysfunction in the clinical setting. Fourteen patients were treated with nivolumab at our institute, of which three developed thyroid dysfunction, an incidence higher than previously reported in the initial clinical trials. Interestingly, one patient achieved complete remission; suggesting that in some patients, the occurrence of immune-related adverse events, including thyroid dysfunction, might reflect the drug's antitumour efficacy. No patient died or discontinued nivolumab treatment owing to thyroid dysfunction. Although thyroid dysfunction first appeared to be asymptomatic, two of the three patients developed symptoms related to hypothyroidism soon after, requiring hormone replacement therapy. Another patient developed hyperthyroidism that was initially asymptomatic; the patient subsequently developed myalgia with fever >39.5°C after two additional courses of nivolumab. Treatment with nivolumab was therefore discontinued, and treatment with prednisolone was initiated. Symptoms resolved within a few days, and thyroid function normalized. Thyroid dysfunction is sometimes difficult to diagnose because its symptoms similar to those of many other diseases. In addition, thyroid-related immune-related adverse events may present with unique symptoms such as myalgia with high fever, abruptly worsening patients' quality of life. Consequently, thyroid dysfunction should be considered as a possible immune-related adverse event. Thus, it is important to test for thyroid dysfunction at baseline and before the administration of each nivolumab dose if possible. PMID:27012985

  18. Structural rearrangements in the thyroid hormone receptor hinge domain and their putative role in the receptor function.

    PubMed

    Nascimento, Alessandro S; Dias, Sandra Martha Gomes; Nunes, Fábio M; Aparício, Ricardo; Ambrosio, Andre L B; Bleicher, Lucas; Figueira, Ana Carolina M; Santos, Maria Auxiliadora M; de Oliveira Neto, Mário; Fischer, Hannes; Togashi, Marie; Craievich, Aldo F; Garratt, Richard C; Baxter, John D; Webb, Paul; Polikarpov, Igor

    2006-07-14

    The thyroid hormone receptor (TR) D-domain links the ligand-binding domain (LBD, EF-domain) to the DNA-binding domain (DBD, C-domain), but its structure, and even its existence as a functional unit, are controversial. The D domain is poorly conserved throughout the nuclear receptor family and was originally proposed to comprise an unfolded hinge that facilitates rotation between the LBD and the DBD. Previous TR LBD structures, however, have indicated that the true unstructured region is three to six amino acid residues long and that the D-domain N terminus folds into a short amphipathic alpha-helix (H0) contiguous with the DBD and that the C terminus of the D-domain comprises H1 and H2 of the LBD. Here, we solve structures of TR-LBDs in different crystal forms and show that the N terminus of the TRalpha D-domain can adopt two structures; it can either fold into an amphipathic helix that resembles TRbeta H0 or form an unstructured loop. H0 formation requires contacts with the AF-2 coactivator-binding groove of the neighboring TR LBD, which binds H0 sequences that resemble coactivator LXXLL motifs. Structural analysis of a liganded TR LBD with small angle X-ray scattering (SAXS) suggests that AF-2/H0 interactions mediate dimerization of this protein in solution. We propose that the TR D-domain has the potential to form functionally important extensions of the DBD and LBD or unfold to permit TRs to adapt to different DNA response elements. We also show that mutations of the D domain LXXLL-like motif indeed selectively inhibit TR interactions with an inverted palindromic response element (F2) in vitro and TR activity at this response element in cell-based transfection experiments.

  19. Nanogold-functionalized magnetic beads with redox activity for sensitive electrochemical immunoassay of thyroid-stimulating hormone.

    PubMed

    Zhang, Bing; Tang, Dianping; Liu, Bingqian; Cui, Yuling; Chen, Huafeng; Chen, Guonan

    2012-01-20

    A new electrochemical immunosensor for sensitive determination of thyroid-stimulating hormone (TSH) was designed by using redox-active nanogold-functionalized magnetic beads (GoldMag) as signal tags on the nanogold-graphene interface. To construct such GoldMag nanostructures, polyethyleneimine-functionalized magnetic beads (PEI-MBs) were initially prepared by using a wet chemical method, and the electroactive thionine molecules and gold nanoparticles were then alternately immobilized on the surface of PEI-MBs by using an opposite-charged adsorption technique and an in situ synthesis method, respectively. The synthesized GoldMag nanostructures were utilized as signal tags for the label of horseradish peroxidase-anti-TSH conjugates (HRP-anti-TSH). With a sandwich-type immunoassay format, the conjugated signal tags on the transducer were increased with the increasing TSH concentration in the sample, thus enhancing the signal of the electrochemical immunosensor due to the labeled HRP toward the catalytic reduction of H(2)O(2). Under optimal conditions, the current was proportional to the logarithm of TSH concentration ranging from 0.01 to 20 μIU mL(-1) in pH 6.0 HAc-NaAc containing 6 mM H(2)O(2). The detection limit (LOD) was 0.005 μIU mL(-1) TSH at 3s(B). The immunosensor displayed an acceptable reproducibility, stability and selectivity. In addition, the methodology was evaluated with human serum specimens, receiving good correlation with results from commercially available electrochemiluminescent analyzer.

  20. Bisphenol A affects androgen receptor function via multiple mechanisms.

    PubMed

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

    2013-05-25

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR.

  1. Bisphenol A affects androgen receptor function via multiple mechanisms

    PubMed Central

    Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B. Alex; Jetten, Anton M.; Austin, Christopher, P.; Tice, Raymond R.

    2013-01-01

    Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. PMID:23562765

  2. Metastatic Papillary Thyroid Carcinoma with Multifocal Synchronous Transformation to Anaplastic Thyroid Carcinoma

    PubMed Central

    Costa, Jose

    2016-01-01

    Papillary thyroid carcinoma is a common malignancy to affect the thyroid and is typified by a nonaggressive nature and low rates of mortality. In contrast, anaplastic thyroid carcinoma is the most aggressive thyroid malignancy with a mortality rate of nearly 90% and survival typically of only six months after the diagnosis is made. The transformation of papillary thyroid carcinoma to anaplastic thyroid carcinoma is well documented in the literature but is uncommon and in most instances is reported as a case report or small series only. Transformation of papillary thyroid carcinoma to anaplastic thyroid carcinoma usually takes place in the thyroid itself or in the adjacent lymph nodes. Only on rare occasions does a transformation occur in a papillary thyroid carcinoma metastasis outside of these locations. In the present case report and subsequent discussion we highlight an unusual case of PTC with transformation to anaplastic thyroid carcinoma, which is shown to involve numerous locations to include near total lung parenchyma obliteration. We also discuss the differential diagnostic challenges when faced with a thyroid malignancy that is negative for thyroglobulin. PMID:27774331

  3. Thyroid Hormone, Cancer, and Apoptosis.

    PubMed

    Lin, Hung-Yun; Chin, Yu-Tan; Yang, Yu-Chen S H; Lai, Husan-Yu; Wang-Peng, Jacqueline; Liu, Leory F; Tang, Heng-Yuan; Davis, Paul J

    2016-01-01

    Thyroid hormones play important roles in regulating normal metabolism, development, and growth. They also stimulate cancer cell proliferation. Their metabolic and developmental effects and growth effects in normal tissues are mediated primarily by nuclear hormone receptors. A cell surface receptor for the hormone on integrin [alpha]vβ3 is the initiation site for effects on tumor cells. Clinical hypothyroidism may retard cancer growth, and hyperthyroidism was recently linked to the prevalence of certain cancers. Local levels of thyroid hormones are controlled through activation and deactivation of iodothyronine deiodinases in different organs. The relative activities of different deiodinases that exist in tissues or organs also affect the progression and development of specific types of cancers. In this review, the effects of thyroid hormone on signaling pathways in breast, brain, liver, thyroid, and colon cancers are discussed. The importance of nuclear thyroid hormone receptor isoforms and of the hormone receptor on the extracellular domain of integrin [alpha]vβ3 as potential cancer risk factors and therapeutic targets are addressed. We analyze the intracellular signaling pathways activated by thyroid hormones in cancer progression in hyperthyroidism or at physiological concentrations in the euthyroid state. Determining how to utilize the deaminated thyroid hormone analog (tetrac), and its nanoparticulate derivative to reduce risks of cancer progression, enhance therapeutic outcomes, and prevent cancer recurrence is also deliberated. © 2016 American Physiological Society. Compr Physiol 6:1221-1237, 2016. PMID:27347891

  4. Environmental Triggers of Autoimmune Thyroiditis

    PubMed Central

    Burek, C. Lynne; Talor, Monica V.

    2009-01-01

    Autoimmune thyroiditis is among the most prevalent of all the autoimmunities. Autoimmune thyroiditis is multifactorial with contributions from genetic and environmental factors. Much information has been published about the genetic predisposition to autoimmune thyroiditis both in experimental animals and humans. There is, in contrast, very little data on environmental agents that can serve as the trigger or autoimmunity in a genetically predisposed host. The best-established environmental factor is excess dietary iodine. Increased iodine consumption is strongly implicated as a trigger for thyroiditis, but only in genetically susceptible individuals. However, excess iodine is not the only environmental agent implicated as a trigger leading to autoimmune thyroiditis. There are a wide variety of other synthetic chemicals that affect the thyroid gland or have the ability to promote immune dysfunction in the host. These chemicals are released into the environment by design, such as in pesticides, or as a by-product of industry. Candidate pollutants include polyaromatic hydrocarbons, polybrominated biphenols, and polychlorinated biphenols, among others. Infections are also reputed to trigger autoimmunity and may act alone or in concert with environmental chemicals. We have utilized a unique animal model, the NOD.H2h4 mouse to explore the influence of iodine and other environmental factors on autoimmune thyroiditis. PMID:19818584

  5. Environmental triggers of autoimmune thyroiditis.

    PubMed

    Burek, C Lynne; Talor, Monica V

    2009-01-01

    Autoimmune thyroiditis is among the most prevalent of all the autoimmunities. Autoimmune thyroiditis is multifactorial with contributions from genetic and environmental factors. Much information has been published about the genetic predisposition to autoimmune thyroiditis both in experimental animals and humans. There is, in contrast, very little data on environmental agents that can serve as the trigger for autoimmunity in a genetically predisposed host. The best-established environmental factor is excess dietary iodine. Increased iodine consumption is strongly implicated as a trigger for thyroiditis, but only in genetically susceptible individuals. However, excess iodine is not the only environmental agent implicated as a trigger leading to autoimmune thyroiditis. There are a wide variety of other synthetic chemicals that affect the thyroid gland or have the ability to promote immune dysfunction in the host. These chemicals are released into the environment by design, such as in pesticides, or as a by-product of industry. Candidate pollutants include polyaromatic hydrocarbons, polybrominated biphenols, and polychlorinated biphenols, among others. Infections are also reputed to trigger autoimmunity and may act alone or in concert with environmental chemicals. We have utilized a unique animal model, the NOD.H2(h4) mouse to explore the influence of iodine and other environmental factors on autoimmune thyroiditis. PMID:19818584

  6. [Thyroid dysfunction and the hemostatic system].

    PubMed

    Platonova, N M; Sviridonova, M A; Troshina, E A

    2014-01-01

    Whether there is a link between thyroid dysfunction and different impairments in the hemostatic system is discussed. The level of thyroid hormones is an essential factor that influences the coagulation system. Thyroid dysfunction affects the balance between coagulation and fibrinolysis, by increasing the risk of thrombosis and hemorrhage in hyperthyroidism. However, there is no consensus of opinion regarding the mechanisms of the described hemostatic changes in the literature. PMID:25509900

  7. Evaluation of thyroid tissue by Raman spectroscopy

    NASA Astrophysics Data System (ADS)

    Teixeira, C. S. B.; Bitar, R. A.; Santos, A. B. O.; Kulcsar, M. A. V.; Friguglietti, C. U. M.; Martinho, H. S.; da Costa, R. B.; Martin, A. A.

    2010-02-01

    Thyroid gland is a small gland in the neck consisting of two lobes connected by an isthmus. Thyroid's main function is to produce the hormones thyroxine (T4), triiodothyronine (T3) and calcitonin. Thyroid disorders can disturb the production of these hormones, which will affect numerous processes within the body such as: regulating metabolism and increasing utilization of cholesterol, fats, proteins, and carbohydrates. The gland itself can also be injured; for example, neoplasias, which have been considered the most important, causing damage of to the gland and are difficult to diagnose. There are several types of thyroid cancer: Papillary, Follicular, Medullary, and Anaplastic. The occurrence rate, in general is between 4 and 7%; which is on the increase (30%), probably due to new technology that is able to find small thyroid cancers that may not have been found previously. The most common method used for thyroid diagnoses are: anamnesis, ultrasonography, and laboratory exams (Fine Needle Aspiration Biopsy- FNAB). However, the sensitivity of those test are rather poor, with a high rate of false-negative results, therefore there is an urgent need to develop new diagnostic techniques. Raman spectroscopy has been presented as a valuable tool for cancer diagnosis in many different tissues. In this work, 27 fragments of the thyroid were collected from 18 patients, comprising the following histologic groups: goitre adjacent tissue, goitre nodular tissue, follicular adenoma, follicular carcinoma, and papillary carcinoma. Spectral collection was done with a commercial FTRaman Spectrometer (Bruker RFS100/S) using a 1064 nm laser excitation and Ge detector. Principal Component Analysis, Cluster Analysis, and Linear Discriminant Analysis with cross-validation were applied as spectral classification algorithm. Comparing the goitre adjacent tissue with the goitre nodular region, an index of 58.3% of correct classification was obtained. Between goitre (nodular region and

  8. Can lifestyle modification affect men’s erectile function?

    PubMed Central

    Hehemann, Marah C.

    2016-01-01

    Erectile dysfunction (ED) is a common condition affecting millions of men worldwide. The pathophysiology and epidemiologic links between ED and risk factors for cardiovascular disease (CVD) are well-established. Lifestyle modifications such as smoking cessation, weight reduction, dietary modification, physical activity, and psychological stress reduction have been increasingly recognized as foundational to the prevention and treatment of ED. The aim of this review is to outline behavioral choices which may increase ones risk of developing ED, to present relevant studies addressing lifestyle factors correlated with ED, and to highlight proposed mechanisms for intervention aimed at improving erectile function in men with ED. These recommendations can provide a framework for counseling patients with ED about lifestyle modification. PMID:27141445

  9. Dehydration affects brain structure and function in healthy adolescents.

    PubMed

    Kempton, Matthew J; Ettinger, Ulrich; Foster, Russell; Williams, Steven C R; Calvert, Gemma A; Hampshire, Adam; Zelaya, Fernando O; O'Gorman, Ruth L; McMorris, Terry; Owen, Adrian M; Smith, Marcus S

    2011-01-01

    It was recently observed that dehydration causes shrinkage of brain tissue and an associated increase in ventricular volume. Negative effects of dehydration on cognitive performance have been shown in some but not all studies, and it has also been reported that an increased perceived effort may be required following dehydration. However, the effects of dehydration on brain function are unknown. We investigated this question using functional magnetic resonance imaging (fMRI) in 10 healthy adolescents (mean age = 16.8, five females). Each subject completed a thermal exercise protocol and nonthermal exercise control condition in a cross-over repeated measures design. Subjects lost more weight via perspiration in the thermal exercise versus the control condition (P < 0.0001), and lateral ventricle enlargement correlated with the reduction in body mass (r = 0.77, P = 0.01). Dehydration following the thermal exercise protocol led to a significantly stronger increase in fronto-parietal blood-oxygen-level-dependent (BOLD) response during an executive function task (Tower of London) than the control condition, whereas cerebral perfusion during rest was not affected. The increase in BOLD response after dehydration was not paralleled by a change in cognitive performance, suggesting an inefficient use of brain metabolic activity following dehydration. This pattern indicates that participants exerted a higher level of neuronal activity in order to achieve the same performance level. Given the limited availability of brain metabolic resources, these findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visuo-spatial processing.

  10. Dehydration affects brain structure and function in healthy adolescents.

    PubMed

    Kempton, Matthew J; Ettinger, Ulrich; Foster, Russell; Williams, Steven C R; Calvert, Gemma A; Hampshire, Adam; Zelaya, Fernando O; O'Gorman, Ruth L; McMorris, Terry; Owen, Adrian M; Smith, Marcus S

    2011-01-01

    It was recently observed that dehydration causes shrinkage of brain tissue and an associated increase in ventricular volume. Negative effects of dehydration on cognitive performance have been shown in some but not all studies, and it has also been reported that an increased perceived effort may be required following dehydration. However, the effects of dehydration on brain function are unknown. We investigated this question using functional magnetic resonance imaging (fMRI) in 10 healthy adolescents (mean age = 16.8, five females). Each subject completed a thermal exercise protocol and nonthermal exercise control condition in a cross-over repeated measures design. Subjects lost more weight via perspiration in the thermal exercise versus the control condition (P < 0.0001), and lateral ventricle enlargement correlated with the reduction in body mass (r = 0.77, P = 0.01). Dehydration following the thermal exercise protocol led to a significantly stronger increase in fronto-parietal blood-oxygen-level-dependent (BOLD) response during an executive function task (Tower of London) than the control condition, whereas cerebral perfusion during rest was not affected. The increase in BOLD response after dehydration was not paralleled by a change in cognitive performance, suggesting an inefficient use of brain metabolic activity following dehydration. This pattern indicates that participants exerted a higher level of neuronal activity in order to achieve the same performance level. Given the limited availability of brain metabolic resources, these findings suggest that prolonged states of reduced water intake may adversely impact executive functions such as planning and visuo-spatial processing. PMID:20336685

  11. Functional roles affect diversity-succession relationships for boreal beetles.

    PubMed

    Gibb, Heloise; Johansson, Therese; Stenbacka, Fredrik; Hjältén, Joakim

    2013-01-01

    Species diversity commonly increases with succession and this relationship is an important justification for conserving large areas of old-growth habitats. However, species with different ecological roles respond differently to succession. We examined the relationship between a range of diversity measures and time since disturbance for boreal forest beetles collected over a 285 year forest chronosequence. We compared responses of "functional" groups related to threat status, dependence on dead wood habitats, diet and the type of trap in which they were collected (indicative of the breadth of ecologies of species). We examined fits of commonly used rank-abundance models for each age class and traditional and derived diversity indices. Rank abundance distributions were closest to the Zipf-Mandelbrot distribution, suggesting little role for competition in structuring most assemblages. Diversity measures for most functional groups increased with succession, but differences in slopes were common. Evenness declined with succession; more so for red-listed species than common species. Saproxylic species increased in diversity with succession while non-saproxylic species did not. Slopes for fungivores were steeper than other diet groups, while detritivores were not strongly affected by succession. Species trapped using emergence traps (log specialists) responded more weakly to succession than those trapped using flight intercept traps (representing a broader set of ecologies). Species associated with microhabitats that accumulate with succession (fungi and dead wood) thus showed the strongest diversity responses to succession. These clear differences between functional group responses to forest succession should be considered in planning landscapes for optimum conservation value, particularly functional resilience.

  12. Environmental Exposures and Autoimmune Thyroid Disease

    PubMed Central

    2010-01-01

    Background Environmental exposures, ranging from perchlorate in rocket fuel to polychlorinated biphenols, have been shown to influence thyroid function. Although most of these agents are associated with reduced thyroid hormone levels or impaired thyroid hormone action, a number of environmental exposures confer an increased risk of autoimmune thyroid disease. Summary Factors that increase autoimmune thyroid disease risk include radiation exposure, both from nuclear fallout and medical radiation, increased iodine intake, as well as several contaminants in the environment that influence the thyroid. Although ∼70% of the risk for developing autoimmune thyroid disease is attributable to genetic background, environmental triggers are thought to play a role in the development of autoimmune thyroid disease in susceptible individuals. Conclusions Understanding the association of environmental agents with thyroid dysfunction can be utilized to reduce the risk to populations. Knowledge of the specific factors that trigger autoimmune thyroid disease and their mode of action, however, may also inform risk reduction in the individual patient. These factors are especially relevant for those at increased risk of autoimmune thyroid disease based on family history. PMID:20578899

  13. Thyroid development in zebrafish lacking Taz.

    PubMed

    Pappalardo, Andrea; Porreca, Immacolata; Caputi, Luigi; De Felice, Elena; Schulte-Merker, Stephan; Zannini, Mariastella; Sordino, Paolo

    2015-11-01

    Taz is a signal-responsive transcriptional coregulator implicated in several biological functions, from chondrogenesis to regulation of organ size. Less well studied, however, is its role in thyroid formation. Here, we explored the in vivo effects on thyroid development of morpholino (MO)-mediated knockdown of wwtr1, the gene encoding zebrafish Taz. The wwtr1 gene is expressed in the thyroid primordium and pharyngeal tissue of developing zebrafish. Compared to mammalian cells, in which Taz promotes expression of thyroid transcription factors and thyroid differentiation genes, wwtr1 MO injection in zebrafish had little or no effect on the expression of thyroid transcription factors, and differentially altered the expression of thyroid differentiation genes. Analysis of wwtr1 morphants at later stages of development revealed that the number and the lumen of thyroid follicles, and the number of thyroid follicle cells, were significantly smaller. In addition, Taz-depleted larvae displayed patterning defects in ventral cranial vessels that correlate with lateral displacement of thyroid follicles. These findings indicate that the zebrafish Taz protein is needed for the normal differentiation of the thyroid and are the first to suggest that Taz confers growth advantage to the endocrine gland.

  14. Effect of metformin on thyroid stimulating hormone and thyroid volume in patients with prediabetes: A randomized placebo-controlled clinical trial

    PubMed Central

    Karimifar, Mozhgan; Aminorroaya, Ashraf; Amini, Masoud; Mirfendereski, Taghi; Iraj, Bijan; Feizi, Awat; Norozi, Atsa

    2014-01-01

    Background: The people with prediabetes have insulin resistance (IR). IR may affect thyroid function, size and nodules. We investigated the effects of metformin on the thyroid gland in prediabetic people. Materials and Methods: In a randomized, double-blind placebo-control clinical trial, 89 people with prediabetes, aged 18-65 years were studied for 3 months. They were divided into two, metformin (n = 43) and placebo (n = 46) treated groups. Serum thyroid stimulating hormone (TSH) was measured and thyroid nodules and volume was studied by ultrasonography. The data were compared between and within groups, before and after the study. Results: Mean of the baseline characteristics in metformin and placebo-treated groups had no statistically significant difference. At the end of the study, serum TSH was not significantly different between the two groups. However, if the TSH range was divided into two low normal (0.3-2.5 μU/ml) and high-normal (2.6-5.5 μU/ml) ranges, significant decrease was observed in metformin-treated group with a high-normal basal serum TSH (P = 0.01). Thyroid volume did not change in metformin-treated group. However, in placebo-treated group, the thyroid was enlarged (P = 0.03). In 53.9% of participants, thyroid nodule was observed. There was just a decrease in the volume of small solid (not mixed) nodules from median of 0.07 ml to 0.04 ml in metformin-treated group (P = 0.01). Conclusion: In prediabetic people, metformin decreases serum TSH, only, in those people with TSH >2.5 μU/ml and reduces the size of small solid thyroid nodules. It also prevents an increase in the thyroid volume. PMID:25657744

  15. The expression of translocator protein in human thyroid cancer and its role in the response of thyroid cancer cells to oxidative stress.

    PubMed

    Klubo-Gwiezdzinska, Joanna; Jensen, Kirk; Bauer, Andrew; Patel, Aneeta; Costello, John; Burman, Kenneth D; Wartofsky, Leonard; Hardwick, Matthew J; Vasko, Vasyl V

    2012-08-01

    The translocator protein (TSPO), formerly known as a peripheral benzodiazepine receptor, exerts pro-apoptotic function via regulation of mitochondrial membrane potential. We examined TSPO expression in human thyroid tumors (25 follicular adenomas (FA), 15 follicular cancers (FC), and 70 papillary cancers (PC)). The role of TSPO in the regulation of cell growth, migration, and apoptosis was examined in thyroid cancer cell lines after TSPO knockdown with siRNA and after treatment with TSPO antagonist (PK11195). Compared with normal thyroid, the level of TSPO expression was increased in FA, FC, and PC in 24, 26.6, and 55.7% of cases respectively. Thyroid cancer cell lines demonstrated variable levels of TSPO expression, without specific association with thyroid oncogene mutations. Treatment with inhibitors of PI3K/AKT or MEK/ERK signaling was not associated with changes in TSPO expression. Treatment with histone deacetylase inhibitor (valproic acid) increased TSPO expression in TSPO-deficient cell lines (FTC236 cells). TSPO gene silencing or treatment with PK11195 did not affect thyroid cancer cell growth and migration but prevented depolarization of mitochondrial membranes induced by oxidative stress. Induction of TSPO expression by valproic acid was associated with increased sensitivity of FTC236 to oxidative stress-inducible apoptosis. Overall, we showed that TSPO expression is frequently increased in PC. In vitro data suggested the role of epigenetic mechanism(s) in the regulation of TSPO in thyroid cells. Implication of TSPO in the thyroid cancer cell response to oxidative stress suggested its potential role in the regulation of thyroid cancer cell response to treatment with radioiodine and warrants further investigation.

  16. To what extent does urbanisation affect fragmented grassland functioning?

    PubMed

    van der Walt, L; Cilliers, S S; Kellner, K; Du Toit, M J; Tongway, D

    2015-03-15

    Urbanisation creates altered environments characterised by increased human habitation, impermeable surfaces, artificial structures, landscape fragmentation, habitat loss, resulting in different resource loss pathways. The vulnerable Rand Highveld Grassland vegetation unit in the Tlokwe Municipal area, South Africa, has been extensively affected and transformed by urbanisation, agriculture, and mining. Grassland fragments in urban areas are often considered to be less species rich and less functional than in the more untransformed or "natural" exurban environments, and are therefore seldom a priority for conservation. Furthermore, urban grassland fragments are often being more intensely managed than exurban areas, such as consistent mowing in open urban areas. Four urbanisation measures acting as indicators for patterns and processes associated with urban areas were calculated for matrix areas surrounding each selected grassland fragment to quantify the position of each grassland remnant along an urbanisation gradient. The grassland fragments were objectively classified into two classes of urbanisation, namely "exurban" and "urban" based on the urbanisation measure values. Grazing was recorded in some exurban grasslands and mowing in some urban grassland fragments. Unmanaged grassland fragments were present in both urban and exurban areas. Fine-scale biophysical landscape function was determined by executing the Landscape Function Analysis (LFA) method. LFA assesses fine-scale landscape patchiness (entailing resource conserving potential and erosion resistance) and 11 soil surface indicators to produce three main LFA parameters (stability, infiltration, and nutrient cycling), which indicates how well a system is functioning in terms of fine-scale biophysical soil processes and characteristics. The aim of this study was to determine the effects of urbanisation and associated management practices on fine-scale biophysical landscape function of urban and exurban

  17. To what extent does urbanisation affect fragmented grassland functioning?

    PubMed

    van der Walt, L; Cilliers, S S; Kellner, K; Du Toit, M J; Tongway, D

    2015-03-15

    Urbanisation creates altered environments characterised by increased human habitation, impermeable surfaces, artificial structures, landscape fragmentation, habitat loss, resulting in different resource loss pathways. The vulnerable Rand Highveld Grassland vegetation unit in the Tlokwe Municipal area, South Africa, has been extensively affected and transformed by urbanisation, agriculture, and mining. Grassland fragments in urban areas are often considered to be less species rich and less functional than in the more untransformed or "natural" exurban environments, and are therefore seldom a priority for conservation. Furthermore, urban grassland fragments are often being more intensely managed than exurban areas, such as consistent mowing in open urban areas. Four urbanisation measures acting as indicators for patterns and processes associated with urban areas were calculated for matrix areas surrounding each selected grassland fragment to quantify the position of each grassland remnant along an urbanisation gradient. The grassland fragments were objectively classified into two classes of urbanisation, namely "exurban" and "urban" based on the urbanisation measure values. Grazing was recorded in some exurban grasslands and mowing in some urban grassland fragments. Unmanaged grassland fragments were present in both urban and exurban areas. Fine-scale biophysical landscape function was determined by executing the Landscape Function Analysis (LFA) method. LFA assesses fine-scale landscape patchiness (entailing resource conserving potential and erosion resistance) and 11 soil surface indicators to produce three main LFA parameters (stability, infiltration, and nutrient cycling), which indicates how well a system is functioning in terms of fine-scale biophysical soil processes and characteristics. The aim of this study was to determine the effects of urbanisation and associated management practices on fine-scale biophysical landscape function of urban and exurban

  18. Thyroid hormones in milk and blood of lactating donkeys as affected by stage of lactation and dietary supplementation with trace elements.

    PubMed

    Todini, Luca; Salimei, Elisabetta; Malfatti, Alessandro; Ferraro, Stefano; Fantuz, Francesco

    2012-05-01

    The traditional utilization of donkeys (Equus asinus) as dairy animals has recently attracted substantial scientific interest with regard to human nutrition. Donkey milk is well tolerated by infants with cows' milk allergy, useful in the treatment of human immune-related diseases, in the prevention of atherosclerosis, and in-vitro studies showed an anti-proliferative effect. Active 3-3'-5-triiodothyronine (T3) in colostrum and milk could play different physiological roles, systemic and paracrine, for both the mother and the suckling offspring. The aim was to evaluate whether thyroid hormones (TH) concentrations in milk and blood of lactating donkeys change with the advancing lactation and whether they can be affected by dietary supplementation with several trace elements, some of them directly involved with TH synthesis (I), metabolism (Se) and action (Zn). Sixteen lactating jennies were divided into two groups (CTL and TE). Mixed feed for TE was added with Zn, Fe, Cu, Mn, I, Se and Co. Every 2 weeks milk and blood samples were collected at 11·00. Total concentrations of T3 in milk (T3M) and T3 and T4 in plasma (T3P and T4P) were assayed using ELISA kits, validated for the donkey species. T3M was not correlated with TH concentrations in blood, did not change with the stage of lactation, and was significantly higher in TE (4·09 ± 0·07 ng/ml, mean ± SE) than in CTL group (3·89 ± 0·08 ng/ml). T4P (81·8 ± 5·2 ng/ml) and T3P (15·2 ± 1 ng/ml) significantly changed with time, but were not significantly affected by dietary treatment. T3P/T4P ratio was significantly lower in TE group. This study indicates that in donkey milk the concentration of T3, a human-like bioactive compound, can be affected by trace elements intake.

  19. 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.

  20. Subacute thyroiditis (de Quervain) presenting as a painless cold nodule

    SciTech Connect

    Bartels, P.C.; Boer, R.O.

    1987-09-01

    A 49-yr-old woman presented with a solid, painless, nontender nodule in the left thyroid lobe. Thyroid scintigraphy revealed a solitary cold area in the left lobe and a slightly decreased 24-hr radioactive iodine thyroid uptake (9%). Although there were no specific clinical or biochemical signs suggesting thyroiditis needle aspiration cytology showed the presence of a subacute thyroiditis. Approximately 1 mo later the entire thyroid gland was affected leading to a completely suppressed thyroid radioiodine uptake and elevated serum thyroid hormone concentrations. This case illustrates that in the early phase of the disease, subacute thyroiditis may present as a solitary, painless, cold nodule and should be considered in the differential diagnosis of such lesions.

  1. Integrating Negative Affect Measures in a Measurement Model: Assessing the Function of Negative Affect as Interference to Self-Regulation

    ERIC Educational Resources Information Center

    Magno, Carlo

    2010-01-01

    The present study investigated the composition of negative affect and its function as inhibitory to thought processes such as self-regulation. Negative affect in the present study were composed of anxiety, worry, thought suppression, and fear of negative evaluation. These four factors were selected based on the criteria of negative affect by…

  2. Diagnosis and management of thyroid disease in pregnancy.

    PubMed

    Fitzpatrick, Diana L; Russell, Michelle A

    2010-06-01

    Thyroid disease is common, affecting 1% to 2% of pregnant women. Pregnancy may modify the course of thyroid disease, and pregnancy outcomes can depend on optimal management of thyroid disorders. Consequently, obstetric providers must be familiar with thyroid physiology and management of thyroid diseases in pregnancy. Following a brief overview of physiology, this article provides an in-depth review of diagnosis and management of the spectrum of thyroid disease occurring in pregnancy. Recommendations for screening and treatment of hypo- and hyperthyroidism are summarized. Specific attention is given to the limitations of current research and the status of ongoing work.

  3. Does Ramadan Fasting Adversely Affect Cognitive Function in Young Females?

    PubMed Central

    Ghayour Najafabadi, Mahboubeh; Rahbar Nikoukar, Laya; Memari, Amir; Ekhtiari, Hamed; Beygi, Sara

    2015-01-01

    We examined the effects of Ramadan fasting on cognitive function in 17 female athletes. Data were obtained from participants of two fasting (n = 9) and nonfasting (n = 8) groups at three periods of the study (before Ramadan, at the third week in Ramadan, and after Ramadan). Digit span test (DST) and Stroop color test were employed to assess short-term memory and inhibition/cognitive flexibility at each time point. There were no significant changes for DST and Stroop task 1 in both groups, whereas Stroop task 2 and task 3 showed significant improvements in Ramadan condition (p < 0.05). Interference indices did not change significantly across the study except in post-Ramadan period of fasting group (p < 0.05). Group × week interaction was significant only for error numbers (p < 0.05). Athletes in nonfasting showed a significant decrease in number of errors in Ramadan compared to baseline (p < 0.05). The results suggest that Ramadan fasting may not adversely affect cognitive function in female athletes. PMID:26697263

  4. Thyroid disorders-assessments of trace elements, clinical, and laboratory parameters.

    PubMed

    Przybylik-Mazurek, Elwira; Zagrodzki, Paweł; Kuźniarz-Rymarz, Sylwia; Hubalewska-Dydejczyk, Alicja

    2011-06-01

    The trace elements studied in this work (Se, Cu, Zn) are the essential constituents or cofactors required to activate numerous enzymes and proteins, playing crucial role in various physiological processes. The disturbed levels of abovementioned elements may adversely affect the endocrine system, resulting in various thyroid disorders among other upsets. The aim of this study was to investigate possible associations between them and parameters of redox balance, thyroid function indices as well as clinical records (duration of disease and therapy, lag time between thyroid surgery and this study examination, LT4 dosage) in patients with different thyroid disorders, including malignant diseases of the gland. In the group of patients with papillary carcinoma, we found a statistically significant higher Cu concentration compared with controls and patients with Hashimoto disease. In the same groups, the parameter of Zn/Cu ratio demonstrated reciprocally arranged statistically significant differences. For the group of papillary cancer patients, there was a negative correlation between lag time since thyroid operation and GPX3 activity. Our data support hypothesis of indirect involvement of Zn and Cu in thyroid regulation. For selenium, lack of simple correlation between its serum level and thyroid indices implies the need for further research on other selenium status parameters more adequately depicting changes in endocrine system.

  5. Thyroid disruption in the lizard Podarcis bocagei exposed to a mixture of herbicides: a field study.

    PubMed

    Bicho, Rita C; Amaral, Maria José; Faustino, Augusto M R; Power, Deborah M; Rêma, Alexandra; Carretero, Miguel A; Soares, Amadeu M V M; Mann, Reinier M

    2013-01-01

    Pesticide exposure has been related with thyroid disrupting effects in different vertebrate species. However, very little is known about the effects of these compounds in reptiles. In the Mediterranean area, lacertid lizards are the most abundant vertebrate group in agroecosystems, and have been identified as potential model species for reptile ecotoxicology. The aim of this study was to understand if the herbicides applied in corn fields have thyroid disruptive effects in the lizard Podarcis bocagei. Adult male lizards were captured in north-western Portugal in corn fields treated with herbicides (exposed sites), and in organic agricultural fields (reference sites). Thyroid and male gonad morphology and functionality, and testosterone levels were investigated through histological, immunohistochemical and biochemical techniques. Lizards from exposed locations displayed thyroid follicular lumens with more reabsorption vacuoles and significantly larger follicular area than those from reference fields. Furthermore, testes of lizards from exposed locations had significantly larger seminiferous tubule diameters, significantly higher number of spermatogenic layers and displayed an up-regulation of thyroid hormone receptors when compared with lizards from reference areas. These findings strongly suggest that the complex mixture of herbicides that lizards are exposed to in agricultural areas have thyroid disrupting effects which ultimately affect the male reproductive system. Alachlor, which has demonstrated thyroid effects in mammals, may be largely responsible for the observed effects.

  6. The effect of a nutritionally-balanced cassava (Manihot esculenta Crantz) diet on endocrine function using the dog as a model. 2. Thyroid.

    PubMed

    Kamalu, B P; Agharanya, J C

    1991-05-01

    Growing dogs were divided into three groups and were fed on nutritionally-balanced diets. Control dogs were fed on a rice diet, the cassava (gari) group ate a diet in which gari provided the carbohydrate source, while the rice + cyanide group consumed the rice diet to which hydrocyanic acid (equivalent to that present in gari) was added. Each group consumed its diet for 14 weeks, during which plasma thiocyanate concentration and total serum triiodothyronine (T3) were monitored. At the end of the experiment the concentrations of the plasma free amino acids phenylalanine and tyrosine, the thyroid weights and histology were determined. While plasma thiocyanate remained undetectable in control dogs, animals consuming both gari and rice + cyanide generated significant amounts. In the control dogs and the gari group, total serum T3 increased 40 and 38.8% respectively from the basal level by the end of the period (P less than 0.02). In contrast there was a decrease in T3 by 36% in the dogs fed on rice + cyanide (P less than 0.05). This group also showed significant thyroid enlargement and a histological picture consistent with parenchymatous goitre, whereas the gari group was essentially normal. The relatively low mean thyroid weight, the rise in total serum T3 level and the normal histological appearance of the gland indicate that dogs that consumed the gari diet were essentially normal with respect to their thyroid function, in spite of their high blood thiocyanate content. In contrast, dogs that consumed rice with cyanide suffered from hypothyroidism and goitre.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1878357

  7. Thyroid hormone receptor-α deletion decreases heart function and exercise performance in apolipoprotein E-deficient mice.

    PubMed

    Liu, Kiao Ling; Canaple, Laurence; Del Carmine, Peggy; Gauthier, Karine; Beylot, Michel; Lo, Ming

    2016-02-01

    The deletion of thyroid hormone receptor-α (TRα) in atherosclerosis-prone apolipoprotein E-deficient (ApoE(-/-)) mice (ApoE(-/-)TRα(0/0)) accelerates the formation of atherosclerotic plaques without aggravation of hypercholesterolemia. To evaluate other predisposition risk factors to atherosclerosis in this model, we studied blood pressure (BP) and cardiac and vascular functions, as well as exercise tolerance in young adult ApoE(-/-)TRα(0/0) mice before the development of atherosclerotic plaques. Telemetric BP recorded for 4 consecutive days showed that the spontaneous systolic BP was slightly decreased in ApoE(-/-)TRα(0/0) compared with ApoE(-/-) mice associated with a reduced locomotor activity. The percentage of animals that completed endurance (57% vs. 89%) and maximal running (0% vs. 89% at 46 cm/s speed in ApoE(-/-)TRα(0/0) and ApoE(-/-) mice, respectively) tests was lower in ApoE(-/-)TRα(0/0) mice. Moreover, during the maximal running test, both maximal running speed and running distance were significantly reduced in ApoE(-/-)TRα(0/0) mice, associated with a blunted BP response to exercise. Transthoracic echocardiography revealed a decreased interventricular septum thickness and an increased end-systolic left ventricular volume in ApoE(-/-)TRα(0/0) mice. Accordingly, left ventricular fractional shortening, ejection fraction, and stroke volume were all significantly decreased in ApoE(-/-)TRα(0/0) mice with a concomitant blunted cardiac output. No interstrain difference was observed in vascular reactivity, except that ApoE(-/-)TRα(0/0) mice exhibited an enhanced acetylcholine-induced relaxation in mesenteric and distal femoral arteries. In conclusion, the deletion of TRα in ApoE(-/-) mice alters cardiac structure and contractility; both could contribute to blunted BP response to physical exercise and impaired exercise performance.

  8. 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

  9. Functional Roles Affect Diversity-Succession Relationships for Boreal Beetles

    PubMed Central

    Gibb, Heloise; Johansson, Therese; Stenbacka, Fredrik; Hjältén, Joakim

    2013-01-01

    Species diversity commonly increases with succession and this relationship is an important justification for conserving large areas of old-growth habitats. However, species with different ecological roles respond differently to succession. We examined the relationship between a range of diversity measures and time since disturbance for boreal forest beetles collected over a 285 year forest chronosequence. We compared responses of “functional” groups related to threat status, dependence on dead wood habitats, diet and the type of trap in which they were collected (indicative of the breadth of ecologies of species). We examined fits of commonly used rank-abundance models for each age class and traditional and derived diversity indices. Rank abundance distributions were closest to the Zipf-Mandelbrot distribution, suggesting little role for competition in structuring most assemblages. Diversity measures for most functional groups increased with succession, but differences in slopes were common. Evenness declined with succession; more so for red-listed species than common species. Saproxylic species increased in diversity with succession while non-saproxylic species did not. Slopes for fungivores were steeper than other diet groups, while detritivores were not strongly affected by succession. Species trapped using emergence traps (log specialists) responded more weakly to succession than those trapped using flight intercept traps (representing a broader set of ecologies). Species associated with microhabitats that accumulate with succession (fungi and dead wood) thus showed the strongest diversity responses to succession. These clear differences between functional group responses to forest succession should be considered in planning landscapes for optimum conservation value, particularly functional resilience. PMID:23977350

  10. Systemic sarcoidosis with hypercalcaemia, hypothalamic-pituitary dysfunction and thyroid involvement.

    PubM