Publications by authors named "Roberto B Santos"

Background: Thyroid eye disease (TED) is the most prevalent extrathyroidal manifestation of Graves' disease (GD). Emerging evidence suggests a relationship between elevated total and LDL cholesterol levels and TED. This study aimed to investigate this correlation in the Brazilian population by analyzing data from two tertiary care centers.

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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.

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Objective: Graves' disease (GD) is the main cause of hyperthyroidism among adults. It is an autoimmune condition classically marked by the Merserburg Triad (goiter, thyrotoxicosis, and orbitopathy), but the change in presentation of GD over time has rarely been studied. To determine changes in the clinical presentation of patients with GD in the last 30 years.

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Objective: We aimed to investigate the role of polymorphisms rs225014 and rs12885300 in Graves' disease patients, mainly for controlling body weight following treatment.

Methods: We genotyped 280 GD patients by the time of diagnosis and 297 healthy control individuals using a TaqMan SNP Genotyping technique. We followed up 141 patients for 18.

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Purpose: CTLA4, PTPN22, and CD40 are immune-regulatory genes strongly associated with GD, as well as PPARG, but their clinical significance in different populations is still uncertain.

Methods: We genotyped 282 Brazilian GD patients (234 women and 48 men, 39.80 ± 11.

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Objective: The objective of this report was to describe a patient with Graves acropachy, a rare manifestation of Graves disease (GD) that is clinically defined by skin tightness, digital clubbing, small-joint pain, and soft tissue edema progressing over months or years with gradual curving and enlargement of the fingers.

Methods: The patient was evaluated regarding thyroid function (serum free T4 [FT4] and thyroid-stimulating hormone [TSH] quantifications) and autoimmunity biomarkers (thyroid receptor antibody [TRAb]) as well as radiographic investigation of the extremities.

Results: A 52-year-old man presented with a history of thyrotoxicosis and clinical signs of Graves orbitopathy.

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Background: Low doses of antithyroid drugs (ATD) for extended periods may be an alternative for Graves' disease (GD) patients who relapse after a course of ATD.

Methods: Patients with GD relapse (n = 238) after discontinuation of ATD therapy for 12-24 months were retrospectively analyzed in a nonrandomized study. Radioiodine (RAI) treatment and L-thyroxine replacement was used in 114 patients, and a low dose of methimazole (MMI; 2.

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In this work the distribution of potassium in sugarcane has been studied during its growth. The soil was prepared with natural fertilizers prepared with sugarcane bagasse. For the measurement of potassium concentration in each part of the plant, gamma-ray spectrometry was used to measure gamma-rays emitted from the radioisotope (40)K.

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Aim: To investigate the effectiveness of 2 fixed iodine (¹³¹I) doses for the treatment for Graves hyperthyroidism and their impact on eye disease.

Methods: We prospectively examined 76 patients who received a fixed dose of 370 MBq (group 1) and 52 patients who received 555 MBq ¹³¹I (group 2). Patients were followed up for 12 months and considered in remission when they were in a stable euthyroid or hypothyroid state in the absence of antithyroid drugs 12 months after ¹³¹I administration.

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Objective: An inherited profile of genes related to the response to aggressive environmental factors such as viruses and chemicals may be related to an increased susceptibility to Graves' disease (GD).

Design And Methods: This prospective case-control study was designed to examine the relationship between human herpesviruses (HHV) infection, determined by circulating DNA; tumour protein p53 (TP53) apoptotic ability; and detoxification system genes, and GD. We studied 280 confirmed GD patients paired to 284 controls with respect to environmental exposure.

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Objective: Cigarette smoking is a well-recognized risk factor of Graves' disease and, particularly, Graves' ophthalmopathy. Hence, germline polymorphisms of detoxification genes and genes belonging to the major DNA repair-apoptosis pathways might have an important role in disease susceptibility. In addition, as some of these genes are regulated by thyroid hormones, they may affect the patients' outcomes.

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Nonmedullary thyroid carcinoma, originating from thyroid epithelial cells, is the most frequent thyroid malignant neoplasia. Since 1955, there has been increasing evidence that this cancer may have a familial predisposition. It is now established that around 4.

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In order to assess the effect of propylthiouracil (PTU) or methimazole (MMI) pretreatment on patient outcome after radioiodine therapy, we examined 100 patients with Graves' disease 3, 6, 9, and 12 months after administration of a 10-mCi standard single dose of 131I. They were assigned to one of three groups: no drug (ND) treatment (30 cases); MMI (45 cases); and PTU (25 cases). Antithyroid drugs (ATD) were withdrawn 15 days before radioiodine administration.

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