THE BIOSYNTHESIS OF THYROXINE AND 3:5:3′-TRIIODOTHYRONINE IN LARVAL AND ADULT TOADS

1959 ◽  
Vol 18 (1) ◽  
pp. 98-101 ◽  
Author(s):  
CLAIRE J. SHELLABARGER ◽  
JUDITH R. BROWN
Keyword(s):  
Thyroid Gland ◽  
Xenopus Laevis ◽  
Thyroid Hormones ◽  
Radioactive Iodine ◽  
Early Stages

SUMMARY 1. A study has been made of the compounds synthesized by and present in the thyroid gland of larval and adult Xenopus laevis using radioactive iodine and chromatography. 2. Tadpoles undergoing active metamorphosis produced thyroxine and trace amounts of 3:5:3′-triiodothyronine. Less thyroxine and no triiodothyronine was detected in tadpoles approaching the end of metamorphosis, and neither compound was detected in tadpoles in early stages of metamorphosis. Adult toads produced thyroxine and trace amounts of triiodothyronine. The presence of monoiodotyrosine and diiodotyrosine was a constant finding. 3. It is suggested that the synthesis of thyroid hormones in amphibia is similar to that in other vertebrates.

scholarly journals Graves’ Disease

2021 ◽  
Author(s):  
Paula Aragão Prazeres de Oliveira ◽  
Beatriz Nayara Muniz de Oliveira ◽  
Eduarda da Silva Souza Paulino ◽  
Fernanda Carolinne Marinho de Araujo ◽  
Paula Gabriele Tabosa Lyra
Keyword(s):  
Thyroid Gland ◽  
Thyroid Hormones ◽  
Radioactive Iodine ◽  
Clinical Manifestations ◽  
Nodular Goiter ◽  
Graves Disease ◽  
Decompression Surgery ◽  
Excessive Sweating ◽  
Toxic Nodular Goiter ◽  
Diffuse Goiter

DG presents with three main presentations: hyperthyroidism with diffuse goiter, infiltrative ophthalmopathy and pre-tibial myxedema. Patients with Graves’ disease can rarely develop severe hyperthyroidism. The hyperthyroidism of Graves’ disease is characterized immunologically by the lymphocytic infiltration of the thyroid gland and by the activation of the immune system with elevation of the circulating T lymphocytes. In GD, goiter is characteristically diffuse. May have asymmetric or lobular character, with variable volume. The clinical manifestations of hyperthyroidism are due to the stimulatory effect of thyroid hormones on metabolism and tissues. Nervousness, eye complaints, insomnia, weight loss, tachycardia, palpitations, heat intolerance, damp and hot skin with excessive sweating, tremors, hyperdefecation and muscle weakness are the main characteristics. In the laboratory diagnosis, biochemical and hormonal exams will be done to assess thyroid hormones and the antithyroid antibodies. Additionally, imaging tests may be performed, such as radioactive iodine capture in 24 hours, ultrasonography, thyroid scintigraphy and fine needle aspiration. It is necessary to make the differential diagnosis of Graves’ disease for thyrotoxicosis, subacute lymphocytic thyroiditis and toxic nodular goiter. The treatment of DG aims to stop the production of thyroid hormones and inhibit the effect of thyroid hormones on the body. Hyperthyroidism caused by DG can be treated in the following ways: it may be the use of synthetic antithyroid medicines, thionamides, MMI being a long-term medicine, it allows a single daily dose, and adherence to treatment occurs, a disadvantage is that it cannot be used in pregnant women; beta-blockers, preferably used in the initial phase of DG with thionamides; radioactive iodine therapy (RAI), being the best cost–benefit and preventing DG recurrence; finally the total thyroidectomy, causing the withdrawal of the thyroid gland. Therefore, it should be discussed with the patient what is the best treatment for your case, with a view to the post and against each approach. If the patient develops Graves ophthalmopathy, in lighter cases the artificial tears should be used, and in more severe cases can be used as treatment, corticosteroids, orbital decompression surgery, prisms and orbital radiotherapy. In addition, the patient should keep their body healthy, doing exercise and healthy eating, following the guidance of their doctor.

TUMOURS OF THE HYPOPHYSIS AND THE THYROID IN MICE

1955 ◽  
Vol 18 (4) ◽  
pp. 445 ◽  
Author(s):  
O. Mühlbock
Keyword(s):  
Thyroid Gland ◽  
Radioactive Iodine ◽  
Thyroid Tissue ◽  
Prolonged Treatment ◽  
Genetic Constitution ◽  
Thiouracil Derivatives

SUMMARY Hypophyseal tumours in mice develop after prolonged treatment with oestrogens, after injection of radioactive iodine in doses which destroy the thyroid tissue and after prolonged treatment with thiouracil-derivatives. The tumours of the hypophysis only occur in certain strains of mice and hence the genetic constitution is of importance. The origin of this difference between strains has hitherto remained completely obscure. The hypophyseal tumours in mice seen following administration of oestrogens and those observed after destruction of the thyroid gland are morphologically similar. They consist of cells staining blue to varying degrees, and they may thus be termed amphophile tumours. The possible mechanism of development of the hypophyseal tumours has been discussed.

THYROID DYSFUNCTION IN PATIENTS WITH CHRONIC KIDNEY DISEASE: THE STATE OF THE PROBLEM AND THE WAYS OF SOLVING

2018 ◽  
Vol 22 (4) ◽  
pp. 40-49 ◽  
Author(s):  
A. R. Volkova ◽  
O. D. Dygun ◽  
B. G. Lukichev ◽  
S. V. Dora ◽  
O. V. Galkina
Keyword(s):  
Chronic Kidney Disease ◽  
Thyroid Gland ◽  
Kidney Disease ◽  
Thyroid Hormones ◽  
Thyroid Function ◽  
Thyroid Dysfunction ◽  
The Body ◽  
Type I ◽  
Low T3 ◽  
Iodine Excretion

Disturbance of the thyroid function is often detected in patients with different profiles. A special feature of patients with chronic kidney  disease is the higher incidence of various thyroid function  disturbances, especially hypothyroidism. It is known that in patients  with chronic kidney disease (CKD) iodine excretion from the body is  violated, since normally 90% of iodine is excreted in urine.  Accumulation of high concentrations of inorganic iodine leads to the  formation of the Wolf-Chaikoff effect: suppression of iodine  organization in the thyroid gland and disruption of the thyroid  hormones synthesis. Peripheral metabolism of thyroid hormones is  also disturbed, namely, deiodinase type I activity is suppressed and  peripheral conversion of T4 into T3 is inhibited (so-called low T3  syndrome). Therefore, patients with CKD are often diagnosed with  hypothyroidism, and the origin of hypothyroidism is not always  associated with the outcome of autoimmune thyroiditis. The article  presents an overview of a large number of population studies of  thyroid gland dysfunction in patients with CKD, as well as  experimental data specifying the pathogenetic mechanisms of  thyroid dysfunction in patients with CKD. Therapeutic tactics are still  not regulated. However, in a number of studies, replacement therapy with thyroid hormones in patients with CKD had some advantages.

scholarly journals The thyroid hormone receptor gene (c-erbA alpha) is expressed in advance of thyroid gland maturation during the early embryonic development of Xenopus laevis.

1991 ◽  
Vol 11 (10) ◽  
pp. 5079-5089 ◽  
Author(s):  
D E Banker ◽  
J Bigler ◽  
R N Eisenman
Keyword(s):  
Gene Expression ◽  
Thyroid Hormone ◽  
Thyroid Gland ◽  
Xenopus Laevis ◽  
Hormone Receptor ◽  
Hormone Receptors ◽  
Thyroid Hormone Receptor ◽  
Thyroid Hormone Receptors ◽  
Stages Of Development ◽  
Xenopus Development

The c-erbA proto-oncogene encodes the thyroid hormone receptor, a ligand-dependent transcription factor which plays an important role in vertebrate growth and development. To define the role of the thyroid hormone receptor in developmental processes, we have begun studying c-erbA gene expression during the ontogeny of Xenopus laevis, an organism in which thyroid hormone has well-documented effects on morphogenesis. Using polymerase chain reactions (PCR) as a sensitive assay of specific gene expression, we found that polyadenylated erbA alpha RNA is present in Xenopus cells at early developmental stages, including the fertilized egg, blastula, gastrula, and neurula. By performing erbA alpha-specific PCR on reverse-transcribed RNAs from high-density sucrose gradient fractions prepared from early-stage embryos, we have demonstrated that these erbA transcripts are recruited to polysomes. Therefore, erbA is expressed in Xenopus development prior to the appearance of the thyroid gland anlage in tailbud-stage embryos. This implies that erbA alpha/thyroid hormone receptors may play ligand-independent roles during the early development of X. laevis. Quantitative PCR revealed a greater than 25-fold range in the steady-state levels of polyadenylated erbA alpha RNA across early stages of development, as expressed relative to equimolar amounts of total embryonic RNA. Substantial increases in the levels of erbA alpha RNA were noted at stages well after the onset of zygotic transcription at the mid-blastula transition, with accumulation of erbA alpha transcripts reaching a relative maximum in advance of metamorphosis. We also show that erbA alpha RNAs are expressed unequally across Xenopus neural tube embryos. This differential expression continues through later stages of development, including metamorphosis. This finding suggests that erbA alpha/thyroid hormone receptors may play roles in tissue-specific processes across all of Xenopus development.

Papillary carcinoma of the thyroid gland in a child of thyrotoxicosis patient receiving radioactive iodine therapy: report of a case

2008 ◽  
Vol 24 (6) ◽  
pp. 747-750 ◽  
Author(s):  
Surasak Sangkhathat ◽  
Sakda Patrapinyokul ◽  
Piyawan Chiengkriwate ◽  
Supika Kritsaneepaiboon ◽  
Kanita Kayasut ◽  
...  
Keyword(s):  
Thyroid Gland ◽  
Papillary Carcinoma ◽  
Radioactive Iodine ◽  
Radioactive Iodine Therapy

Dynamics of Thyroid Hormones at Early Stages of Development of the Sturgeon Acipenser güldenstadti

2004 ◽  
Vol 40 (2) ◽  
pp. 176-181 ◽  
Author(s):  
N. E. Boiko ◽  
O. A. Vorob'eva ◽  
R. A. Grigor'yan ◽  
G. G. Kornienko
Keyword(s):  
Thyroid Hormones ◽  
Stages Of Development ◽  
Early Stages

scholarly journals ENGLISH VERSION: AGE FEATURES OF RADIOACTIVE IODINE (131I) ABSORPTION BY RAT THYROID GLANDS IN CORRECTION OF THE DIETARY IODINE DEFICIENCY WITH ORGANIC IODINE

2021 ◽  
Vol 25 (1-2) ◽  
pp. 31-35
Author(s):  
O.I. Ryabukha
Keyword(s):  
Thyroid Gland ◽  
Iodine Deficiency ◽  
Radioactive Iodine ◽  
Male Rats ◽  
Organic Iodine ◽  
Study Results ◽  
Thyroid Glands ◽  
Immature Rats ◽  
Old Rats ◽  
Rat Thyroid

The structure of endocrine morbidity is characterized by a significant spread of thyroid pathology. The insufficient efficacy of inorganic iodine drugs poses the problem of search for new means for iodine deficiency treatment and prevention. Given the progressive aging of the population in economically developed countries, the purpose of the study was to clarify the effect of organic iodine on the features of absorption and elimination of radioactive iodine from the thyroid glands of variously aged rats in the conditions of iodine deficiency in the diet. The study was performed on nonlinear white male rats in two series of studies that were kept on iodine-deficient isocaloric starch-casein diet for 60 days: the first series included two groups of old rats weighing 0.400-0.450 kg, the second series – two groups of sexually immature rats weighing 0.060-0.090 kg. There were 5 rats in each group. In animals of the experimental groups in each series, 10% of casein in the diet was replaced with organic iodine, which came with iodine-protein preparation from the red Black Sea algae Phyllophora nervosa. The functional state of the thyroid gland was studied using the Sodium Iodide Na 131 I Injection drug. The dosimetry was performed using the STS-6 Geiger-Muller Detector. Radioindication of the thyroid gland was carried out after subcutaneous administration of 0.1 ml of 131I solution at the following time intervals: 0.5, 1, 2, 4, 6, 8, 10, 12, 24, 48, 72, and 96 hours after administration of 131I. The study results were presented as a percentage of the radioiodine dose administered, adjusted for natural radioactivity background and the radioactive decay of the drug. It was found that in the iodine deficiency conditions, the thyroid glands of old rats have higher rates of radioiodine absorption and a lower rate of its excretion than the glands of immature rats, which indicates their lower iodine reserve and greater liability to iodine deficiency pathology. Intake of organic iodine regardless of the rats’ age is accompanied by a decrease in radioiodine accumulation and acceleration of its excretion from the thyroid gland, which indicates a decrease in functional stress, but the glands of older rats absorb more iodine and excrete it more slowly, indicating less effective correction of iodine deficiency with age. Reduced functional activity of the thyroid glands in old rats can be used as a sensitive changes marker for the in-depth study of thyrotropic and thyroid disrupting effects.

scholarly journals Thyrotoxicosis treatment with lithium corbanate. Cases reported

2021 ◽  
Vol 17 (3) ◽  
pp. 22-26
Author(s):  
I. A. Matsueva ◽  
A. B. Dalmatova ◽  
T. V. Andreychenko ◽  
E. N. Grineva
Keyword(s):  
Side Effects ◽  
Thyroid Gland ◽  
Thyroid Hormones ◽  
Toxic Hepatitis ◽  
Lithium Carbonate ◽  
Graves Disease ◽  
Allergic Reactions ◽  
Low Doses ◽  
Short Course ◽  
Toxic Goiter

Treatment of thyrotoxicosis caused by Graves’ disease or multinodular toxic goiter, is not difficult, in most cases, since the prescription of thionamides allows to normalize the level of thyroid hormones quickly and safety. But in a number of cases this therapy might be associated with serious side effects (agranulocytosis, toxic hepatitis, cholestasis), severe allergic reactions and also individual intolerance on thionamides. In such cases lithium carbonate is used, especially in severe thyrotoxic syndrome. It is known, that lithium can accumulate in the thyroid gland at a concentration 3–4 times higher than in the plasma. Perhaps, lithium uses Na+/I- ions. It can inhibit the synthesis and secretion thyroid hormones of thyroid gland. The article presents the cases reported the use of lithium carbonate in thyrotoxicosis treatment before thyroidectomy. Administering low doses of carbonate lithium (900 mg/ per day) renders significant decrease or normalization of thyroid hormones concentration within 7–14 days, thus it let perform thyroidectomy on the patients. No side effects have been identified with such a short course of lithium carbonate treatment.

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