Do Prognostic Differences Exist Among High-Risk Mutations? A Comparison of Outcomes Between the C634R and Other C634 Mutations in Hereditary Medullary Thyroid Carcinoma.

The American Thyroid Association has stratified C634 mutations as high risk. The association between C634R mutation and a more aggressive medullary thyroid carcinoma (MTC) behavior compared with other C634 mutations remains inconclusive, possibly due to the lack of large cohorts and long-term outcome data. This study aimed to evaluate the aggressiveness and long-term outcomes of hereditary MTC in patients with different codon 634 mutations.

Evaluation of Anti-Thyroperoxidase (A-TPO) and Anti-Thyroglobulin (A-Tg) Antibodies in Women with Previous Hashimoto's Thyroiditis during and after Pregnancy.

Autoimmune thyroid diseases (AITD) affect 2 to 5% of the general population. This study aimed to determine changes in activity of A-Tg and A-TPO antibodies before, during, and after pregnancy in women with previous AITD. This was a single-center study with a retrospective review of the medical records of 30 female patients aged 25-41 years who came to our endocrinology service in the city of Santo André, state of São Paulo, Brazil, to investigate thyroid diseases.

Long-Term Follow-up of Patients With Autonomous Thyroid Nodules Treated With Radioiodine.

Purpose: This article aims to describe the presentation of Plummer disease and its evolution after radioiodine treatment and determine factors that may influence treatment efficacy.

Patients And Methods: The sample included retrospective medical records of 165 adult patients with toxic nodular goiter treated with radioiodine between 1997 and 2017, followed up at a single thyroid center.

Results: The efficacy of treatment with a single dose of radioiodine was higher than 90%.

RET 634 germline/gonadal mosaicism generating a second pathogenic amino acid change in multiple endocrine neoplasia type 2A.

Genetic testing for germline RET pathogenic variants, which cause the Multiple Endocrine Neoplasia Type 2 (MEN2) syndrome, has become crucial in managing patients with medullary thyroid carcinoma (MTC). Classically, RET heterozygous missense pathogenic variants are transmitted in a Mendelian autosomal dominant pattern, of which germline/gonadal mosaicism has never been reported. We report the novel occurrence of a MEN2A patient's family in which the siblings inherited three different RET 634 genotypes: wild type (p.

Risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy in thyroid nodules with diameters greater than 4 centimeters.

Objective: The risk of malignancy and diagnostic accuracy of fine-needle aspiration biopsy (FNAB) of thyroid nodules (TN) with diameters ≥ 3-4 cm remains controversial. However, some groups have indicated surgical treatment in these patients regardless of the FNAB results. We aimed to evaluate the diagnostic accuracy of the FNAB in systematically resected ≥4 cm TN and if the risk of malignancy is higher in these patients.

Serum Thyrotropin and Triiodothyronine Levels in Levothyroxine-treated Patients.

Context: Small adjustments in levothyroxine (LT4) dose do not appear to provide clinical benefit despite changes in thyrotropin (TSH) levels within the reference range. We hypothesize that the accompanying changes in serum total triiodothyronine (T3) levels do not reflect the magnitude of the changes in serum TSH.

Objective: This work aims to characterize the relationships of serum free thyroxine (FT4) vs T3, FT4 vs TSH, and FT4 vs the T3/FT4 ratio.

Triiodothyronine Treatment reverses Depression-Like Behavior in a triple-transgenic animal model of Alzheimer's Disease.

Alzheimer disease's (AD) is a neurodegenerative disorder characterized by cognitive and behavioral impairment. The central nervous system is an important target of thyroid hormones (TH). An inverse association between serum triiodothyronine (T3) levels and the risk of AD symptoms and progression has been reported.

Recurrence of COVID-19 associated with reduced T-cell responses in a monozygotic twin pair.

Recurrence of COVID-19 in recovered patients has been increasingly reported. However, the immune mechanisms behind the recurrence have not been thoroughly investigated. The presence of neutralizing antibodies (nAbs) in recurrence/reinfection cases suggests that other types of immune response are involved in protection against recurrence.

Regularly swimming exercise modifies opioidergic neuromodulation in rostral ventrolateral medulla in hypertensive rats.

Moderate exercise reduces arterial pressure (AP) and heart rate (HR) in spontaneously hypertensive rats (SHR) and changes neurotransmission in medullary areas involved in cardiovascular regulation. We investigated if regularly swimming exercise (SW) affects the cardiovascular adjustments mediated by opioidergic neuromodulation in the RVLM in SHR and Wistar-Kyoto (WKY) rats. Rats were submitted to 6 wks of SW.

GLOBAL ENDOCRINOLOGY: Geographical variation in the profile of RET variants in patients with medullary thyroid cancer: a comprehensive review.

Genetic variability in humans is influenced by many factors, such as natural selection, mutations, genetic drift, and migrations. Molecular epidemiology evaluates the contribution of genetic risk factors in the etiology, diagnosis, and prevention of a particular disease. Few areas of medicine have been so clearly affected by genetic diagnosis and management as multiple neoplasia type 2 (MEN2), in which activating pathogenic variants in the RET gene results in the development of medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism in nearly 98, 50, and 25% of gene carriers, respectively.

MHC Variants Associated With Symptomatic Asymptomatic SARS-CoV-2 Infection in Highly Exposed Individuals.

Despite the high number of individuals infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) who develop coronavirus disease 2019 (COVID-19) symptoms worldwide, many exposed individuals remain asymptomatic and/or uninfected and seronegative. This could be explained by a combination of environmental (exposure), immunological (previous infection), epigenetic, and genetic factors. Aiming to identify genetic factors involved in immune response in symptomatic COVID-19 as compared to asymptomatic exposed individuals, we analyzed 83 Brazilian couples where one individual was infected and symptomatic while the partner remained asymptomatic and serum-negative for at least 6 months despite sharing the same bedroom during the infection.

Use of Statins Among Patients Taking Levothyroxine: an Observational Drug Utilization Study Across Sites.

Context: Treatment with levothyroxine (LT4) that normalize serum thyrotropin (TSH) is expected to restore lipid metabolism.

Objective: To assess statin utilization in LT4-treated patients through an observational drug utilization study.

Methods: Three sites were involved: (1) 10 723 outpatients placed on LT4 during 2006-2019 identified from the Clinical Research Data Warehouse of the University of Chicago; (2) ~1.

The role of a new polyclonal competitive thyroglobulin assay in the follow-up of patients with differentiated thyroid cancer with structural disease but low levels of serum thyroglobulin by immunometric and LC-MS/MS methods.

Purpose: The aims of this study were to assess the role of an in-house competitive thyroglobulin assay (Tg-c) in the follow-up of metastatic differentiated thyroid carcinoma (DTC) patients who presented underestimated Tg measurements by immunometric assays (Tg-IMA) and to compare the results with IMA and LC-MS/MS Tg methods.

Methods: This prospective study included 40 patients. Twenty-one with metastatic disease: 14 had Tg-IMA levels inappropriately low or undetectable (eight patients with positive and six with borderline TgAb) and seven had high Tg-IMA levels.

Oxytocin Reduces Intravesical Pressure in Anesthetized Female Rats: Action on Oxytocin Receptors of the Urinary Bladder.

Urinary bladder dysfunction affects several people worldwide and shows higher prevalence in women. Micturition is dependent on the Barrington's nucleus, pontine urine storage center and periaqueductal gray matter, but other brain stem areas are involved in the bladder regulation. Neurons in the medulla oblongata send projections to hypothalamic nuclei as the supraoptic nucleus, which synthetizes oxytocin and in its turn, this peptide is released in the circulation.

Liothyronine and Desiccated Thyroid Extract in the Treatment of Hypothyroidism.

The basis for the treatment of hypothyroidism with levothyroxine (LT4) is that humans activate T4 to triiodothyronine (T3). Thus, while normalizing serum thyrotropin (TSH), LT4 doses should also restore the body's reservoir of T3. However, there is evidence that T3 is not fully restored in LT4-treated patients.

Retroposed copies of RET gene: a somatically acquired event in medullary thyroid carcinoma.

Background: Different pathogenic germline mutations in the RET oncogene are identified in MEN 2, a hereditary syndrome characterized by medullary thyroid carcinoma (MTC) and other endocrine tumors. Although genetic predisposition is recognized, not all RET mutation carriers will develop the disease during their lifetime or, likewise, RET mutation carriers belonging to the same family may present clinical heterogeneity. It has been suggested that a single germline mutation might not be sufficient for development of MEN 2-associated tumors and a somatic bi-allelic alteration might be required.

Altered Gene Expression of Thyroid Hormone Transporters and Deiodinases in iPS MeCP2-Knockout Cells-Derived Neurons.

MeCP2 is an X-linked gene; its mutation causes Rett Syndrome (RTT), a severe neurodevelopmental disability that affects mainly girls. Acting as a transcription factor, the MeCP2 protein is able to regulate several hormone-related genes, such as the thyroid hormones (TH), which are known to play an important role in the development of the central nervous system (CNS). Although only a few studies have associated RTT and TH, TH deficit can lead to neurological deregulation by triggering functional deficiencies during adulthood.

Genotype and phenotype landscape of MEN2 in 554 medullary thyroid cancer patients: the BrasMEN study.

Multiple endocrine neoplasia type 2 (MEN2) is an autosomal dominant genetic disease caused by RET gene germline mutations that is characterized by medullary thyroid carcinoma (MTC) associated with other endocrine tumors. Several reports have demonstrated that the RET mutation profile may vary according to the geographical area. In this study, we collected clinical and molecular data from 554 patients with surgically confirmed MTC from 176 families with MEN2 in 18 different Brazilian centers to compare the type and prevalence of RET mutations with those from other countries.

A pioneering RET genetic screening study in the State of Ceará, Brazil, evaluating patients with medullary thyroid cancer and at-risk relatives: experience with 247 individuals.

Objective: Initial diagnosis of medullary thyroid carcinoma (MTC) is frequently associated with advanced stages and a poor prognosis. Thus, the need for earlier diagnoses and detection in relatives at risk for the disease has led to increased use of RET genetic screening.

Subjects And Methods: We performed RET screening in 247 subjects who were referred to the Brazilian Research Consortium for Multiple Endocrine Neoplasia (BRASMEN) Center in the State of Ceará.

Thyroid cancer burden and economic impact on the Brazilian public health system.

Objective: Recent data indicates an increasing incidence of thyroid cancer not accompanied by a proportional increase in mortality, suggesting overdiagnosis, which may represent a big public health problem, particularly where resources are scarce. This article aims to describe and evaluate the procedures related to investigation of thyroid nodules and treatment and follow-up of thyroid cancer and the costs for the Brazilian public health system between 2008 and 2015.

Materials And Methods: Data on procedures related to investigation of thyroid nodules and treatment/follow-up of thyroid cancer between 2008 and 2015 in Brazil were collected from the Department of Informatics of the Brazilian Unified Health System (Datasus) website.

Assessing the clinical and molecular diagnosis of inherited forms of impaired sensitivity to thyroid hormone from a single tertiary center.

Aim: Resistance to thyroid hormone (RTH), characterized by persistent hyperthyroxinemia with non-suppressed thyrotropin (TSH), is mostly caused by mutations in thyroid hormone receptor beta gene (THRB). Two differential diagnoses should be considered due to similar clinical and laboratory findings: TSH-producing pituitary adenoma (TPA) and Familial Dysalbuminemic Hyperthyroxinemia (FDH). The aim of this study is to describe our single tertiary center experience in the molecular diagnosis of RTH in Brazilian patients, analyzing their clinical and laboratory characteristics and the most common differential diagnosis.

Impact of swimming exercise on inflammation in medullary areas of sympathetic outflow control in spontaneously hypertensive rats.

Exercise reduces sympathetic activity (SA), arterial pressure and heart rate in spontaneously hypertensive rats (SHR). Exercise increases oxidative stress (OS) and inflammation is implicated in the generation of reactive oxygen species (ROS) and progression of hypertension. To unravel these effects of exercise and considering that SA is driven by medullary areas, we hypothesized that swimming exercise (SW) affects the gene expression (g.