Histopathological Characterization and Whole Exome Sequencing of Ectopic Thyroid: Fetal Architecture in a Functional Ectopic Gland from Adult Patient.

Ectopic thyroid results from a migration defect of the developing gland during embryogenesis causing congenital hypothyroidism. But it has also been detected in asymptomatic individuals. This study aimed to investigate the histopathological, functional, and genetic features of human ectopic thyroids.

Analysis of the PAX8 gene in 32 children with thyroid dysgenesis and functional characterization of a promoter variant.

Background: The molecular basis underlying the development of thyroid dysgenesis remains largely unknown. The objective of this study was to analyze the PAX8 gene in 32 children with congenital hypothyroidism due to thyroid dysgenesis for mutations, and to characterize the functional consequences of the mutations.

Methods: The 5'-untranslated region and the entire coding region of the PAX8 gene were analyzed in 32 children.

Hypermethylation of a New Distal Sodium/Iodide Symporter (NIS) enhancer (NDE) is associated with reduced NIS expression in thyroid tumors.

Context: In thyroid tumors, reduced radioiodine uptake is associated with worse patient outcome concomitantly with low sodium/iodide symporter (NIS) mRNA expression. Previous studies showed that CpG-island methylation in the NIS proximal promoter does not correlate with mRNA expression.

Objectives: The aim of the study was to identify new CpG-islands within the NIS 5'region and investigate the involvement of their methylation in NIS expression.

Approach to and treatment of goiters.

The main causes of simple diffuse goiter (SDG) and multinodular goiter (MNG) are iodine deficiency, increase in serum thyroid-stimulating hormone (TSH) level, natural goitrogens, smoking, chronic malnutrition, and lack of selenium, iron, and zinc. Increasing evidence suggests that heredity is equally important. Treatment of SDG and MNG still focuses on L-thyroxine-suppressive therapy surgery.

MiR-1 is a tumor suppressor in thyroid carcinogenesis targeting CCND2, CXCR4, and SDF-1alpha.

Context: Micro-RNA have emerged as an important class of short endogenous RNA that act as posttranscriptional regulators of gene expression and are constantly deregulated in human cancer. MiR-1 has been found down-regulated in lung, colon, and prostate cancer.

Objectives: In this study, we investigated the possible role of miR-1 in thyroid carcinogenesis.

Levothyroxine absorption in morbidly obese patients before and after Roux-En-Y gastric bypass (RYGB) surgery.

Background: Roux-en-Y gastric bypass (RYGB) modifies the anatomical structure of the upper intestine tract, reduces gastric acid secretion, and may impair LT4 absorption. The aim of this study was to evaluate the LT4 absorption in morbidly obese patients before and after RYGB.

Methods: Thirty morbidly obese patients were divided in two groups: The NS group included 15 patients before RYGB surgery (BMI = 43.

Lipid metabolism in subclinical hypothyroidism: plasma kinetics of triglyceride-rich lipoproteins and lipid transfers to high-density lipoprotein before and after levothyroxine treatment.

Background: Subclinical hypothyroidism (SCH) has been associated with atherosclerosis, but the abnormalities in plasma lipids that can contribute to atherogenesis are not prominent. The aim of this study was to test the hypothesis that patients with normocholesterolemic, normotriglyceridemic SCH display abnormalities in plasma lipid metabolism not detected in routine laboratory tests including abnormalities in the intravascular metabolism of triglyceride-rich lipoproteins, lipid transfers to high-density lipoprotein (HDL), and paraoxonase 1 activity. The impact of levothyroxine (LT4) treatment and euthyroidism in these parameters was also tested.

Monoallelic thyroid peroxidase gene mutation in a patient with congenital hypothyroidism with total iodide organification defect.

The aim of this study was to identify the genetic defect of a patient with dyshormonogenetic congenital hypothyroidisms (CH) with total iodide organification defect (TIOD). A male child diagnosed with CH during neonatal screening. Laboratory tests confirmed the permanent and severe CH with TIOD (99% perchlorate release).

High prevalence of side effects after recombinant human thyrotropin-stimulated radioiodine treatment with 30 mCi in patients with multinodular goiter and subclinical/clinical hyperthyroidism.

Background: Treatment of multinodular goiters (MNGs) is highly controversial. Radioiodine (RAI) therapy is a nonsurgical alternative for the elderly who decline surgery. Recently, recombinant human thyrotropin (rhTSH) has been used to augment RAI uptake and distribution.

Iodine nutrition in Brazil: where do we stand?

Brazilian legislation, since 1955, failed to achieve its objectives because the issue was not properly addressed: iodized salt was only available in endemic areas, at a low amount of 10 mg Iodine/kg salt. Lack of surveillance and cooperation were common errors. From 1982 to 1992, the INAN distributed potassium iodate to the industry free of charge, but it was abolished in 1991.

Mutations of the thyroglobulin gene and its relevance to thyroid disorders.

Purpose Of Review: To perform an update review on thyroglobulin gene mutations associated with congenital hypothyroidism, thyroid cancer, and autoimmunity.

Recent Findings: Forty-two thyroglobulin mutations have been identified in dyshormonogenetic congenital hypothyroidism. Clinical and laboratory criteria defining defective thyroglobulin synthesis are mostly related to thyroglobulin mutations, generally caused by intracellular thyroglobulin transport defects to the colloid rather than defects in thyroid hormones synthesis.

Excessive iodine intake and ultrasonographic thyroid abnormalities in schoolchildren.

High nutritional levels of iodine may induce a higher prevalence of autoimmune thyroiditis, hypothyroidism, goiter, as well as hyperthyroidism, mostly in the elderly. This study assessed thyroid volume and ultrasonographic abnormalities as well as urinary iodine excretion (UIE) in 964 schoolchildren living in an iodine-sufficient area in southern Brazil. Thyroid volume correlated with age and body surface area in boys and girls.

The p.A2215D thyroglobulin gene mutation leads to deficient synthesis and secretion of the mutated protein and congenital hypothyroidism with wide phenotype variation.

Context: Thyroglobulin (TG) is a large glycoprotein and functions as a matrix for thyroid hormone synthesis. TG gene mutations give rise to goitrous congenital hypothyroidism (CH) with considerable phenotype variation.

Objectives: The aim of the study was to report the genetic screening of 15 patients with CH due to TG gene mutations and to perform functional analysis of the p.

The prevalence of thyroid dysfunction in elderly cardiology patients with mild excessive iodine intake in the urban area of São Paulo.

Objectives: To evaluate the prevalence of thyroid dysfunction in elderly cardiac patients in an outpatient setting.

Subjects And Methods: A total of 399 consecutive patients (268 women, age range 60-92 years) who were followed at Heart Institute were evaluated for thyroid dysfunction with serum free T4, TSH, anti-Peroxidase antibodies, urinary iodine excretion measurements and thyroid ultrasound.

Results: Hyperthyroidism (overt and subclinical) was present in 29 patients (6.

A molecular analysis and long-term follow-up of two siblings with severe congenital hypothyroidism carrying the IVS30+1G>T intronic thyroglobulin mutation.

Objective: To extend the molecular analysis of the IVS30+1G>T intronic thyroglobulin (TG) mutation, and to report the eleven year follow-up of the affected patients. METHOSD: Two siblings with severe congenital hypothyroidism with fetal and neonatal goiter, harboring the IVS30+1G>T mutation were included. Nodular and non-nodular thyroid tissue specimens were collected.

Phenotypic variation among four family members with congenital hypothyroidism caused by two distinct thyroglobulin gene mutations.

Background: Thyroglobulin (Tg) is a large glycoprotein that is intimately involved in the biosynthesis of thyroxine and triiodothyronine. At least 38 mutations have been described in the Tg gene that are associated with varying degrees of hypothyroidism. We studied the Tg gene in four related subjects with congenital hypothyroidism.

Association of low sodium-iodide symporter messenger ribonucleic acid expression in malignant thyroid nodules with increased intracellular protein staining.

Context: The expression of sodium iodide symporter (NIS) is required for iodide uptake in thyroid cells. Benign and malignant thyroid tumors have low iodide uptake. However, previous studies by RT-PCR or immunohistochemistry have shown divergent results of NIS expression in these nodules.

Thyroid and the environment: exposure to excessive nutritional iodine increases the prevalence of thyroid disorders in Sao Paulo, Brazil.

Objective: To evaluate the prevalence of chronic autoimmune thyroiditis (CAT) and iodine-induced hypothyroidism, hyperthyroidism (overt and subclinical), and goiter in a population exposed to excessive iodine intake for 5 years (table salt iodine concentrations: 40-100 mg/kg salt). Design This was a population-based, cross-sectional study with 1085 participants randomly selected from a metropolitan area in São Paulo, Brazil, and conducted during the first semester of 2004.

Methods: Thyroid ultrasound examination was performed in all participants and samples of urine and blood were collected from each subject.

An outline concerning the potential use of recombinant human thyrotropin for improving radioiodine therapy of multinodular goiter.

Radioiodine ((131)I) treatment for nontoxic and toxic multinodular goiter (MNG) is an alternative therapeutic procedure used especially for patients with contraindication for surgery. Several studies have been conducted in recent years assessing the use of recombinant human TSH (rhTSH) in increasing (131)I uptake in MNGs. This procedure also decreases the activity level of the administered (131)I, changes the distribution of (131)I in the thyroid, lowers the absorption dose, and dramatically reduces the volume of the goiter (50-75% of the baseline volume).