Publications (17)45.33 Total impact
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Article: Validation of Reference Genes for Normalizing Gene Expression in Real-Time Quantitative Reverse Transcription PCR in Human Thyroid Cells in Primary Culture Treated with Progesterone and Estradiol.
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ABSTRACT: The use of appropriately chosen reference genes for normalizing gene expression in real-time quantitative reverse transcription polymerase chain reaction is an important step in the analysis of gene expression, compensating for several technical factors. As female sex hormones have been shown to influence growth and differentiation of thyroid follicular cells, the establishment of normalizer genes in human thyroid cells in primary culture, treated with progesterone, and estradiol, is important to evaluate their effect on gene expression in these cells, so candidate reference genes were studied. β-Actin, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), β2-microglobulin (B2M), and TATA box binding protein (TBP) were evaluated in thyroid cells treated with estradiol, progesterone, and their inhibitors. Normfinder software was used to assess the stability of the genes and identified β-actin as the gene with adequate stability and lower inter-group variations, when compared to TBP, B2M, and GAPDH.Molecular Biotechnology 06/2012; · 2.17 Impact Factor -
Article: Hypomagnesemia and proton pump inhibitors: below the tip of the iceberg.
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ABSTRACT: Severe magnesium deficiency associated with proton pump inhibitors (PPIs) has been described recently with clinical presentations varying from life-threatening conditions to muscle cramps and paresthesias. Probably milder cases go undetected. We report an asymptomatic case of hypomagnesemia associated with chronic use of PPIs in a 67-year-old woman. She had had symptoms of gastroesophageal reflux disease for several years, which abated partially with PPIs, and denied any other symptoms or medications. Her initial evaluation showed an unexplained hypomagnesemia with a very low magnesium excretion rate in urine. Serum calcium, phosphorus, potassium, and glucose levels and renal function were normal. After PPI withdrawal, serum and urinary magnesium levels normalized.Archives of internal medicine 05/2011; 171(15):1391-2. · 11.46 Impact Factor -
Article: Effect of High- versus Low-Fat Meal on Serum 25-Hydroxyvitamin D Levels after a Single Oral Dose of Vitamin D: A Single-Blind, Parallel, Randomized Trial.
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ABSTRACT: Background/Aims. Vitamin D(3) is liposoluble, so dietary fat could increase its oral absorption. Our aim was to compare serum 25-hydroxyvitamin D [25(OH)D] after the oral intake of cholecalciferol with a high- or low-fat meal. Methods. In a single-blind, parallel clinical trial, 32 healthy physicians were divided into two groups. In the same day, they ingested 50,000 IU (1.25 mg) of vitamin D(3) with food: group 1 (G1): lipids: 25.6 g and group 2 (G2) lipids: 1.7 g. Serum 25(OH)D (0, 7, and 14 days), and parathyroid hormone (PTH), and calcium (0 and 14 days) were measured. Results. Baseline mean serum 25(OH)D levels were 42.7 ± 19.0 nmol/L in G1 and 36.4 ± 19.0 nmol/L in G2 (P = 0.38). After cholecalciferol, mean serum 25(OH)D was higher in G1 (P < 0.001): 7 days: G1 = 46.2 (38.4-53.9) nmol/L and G2 = 33.7 (25.4-40.1) nmol/L; 14 days: G1 = 53.7 (45.2-62.1) nmol/L and G2 = 33.7 (25.2-42.2) nmol/L. Serum PTH and 25(OH)D were negatively correlated before and after the intake of vitamin D(3), respectively, r = -0.42 (P = 0.02) and r = -0.52 (P = 0.003). Conclusions. A high-fat meal increased the absorption of vitamin D(3), as measured by serum 25(OH)D.International Journal of Endocrinology 01/2011; 2011:809069. · 1.87 Impact Factor -
Article: Role of estrogen in thyroid function and growth regulation.
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ABSTRACT: Thyroid diseases are more prevalent in women, particularly between puberty and menopause. It is wellknown that estrogen (E) has indirect effects on the thyroid economy. Direct effects of this steroid hormone on thyroid cells have been described more recently; so, the aim of the present paper was to review the evidences of these effects on thyroid function and growth regulation, and its mechanisms. The expression and ratios of the two E receptors, α and β, that mediate the genomic effects of E on normal and abnormal thyroid tissue were also reviewed, as well as nongenomic, distinct molecular pathways. Several evidences support the hypothesis that E has a direct role in thyroid follicular cells; understanding its influence on the growth and function of the thyroid in normal and abnormal conditions can potentially provide new targets for the treatment of thyroid diseases.Journal of thyroid research. 01/2011; 2011:875125. -
Article: Prognosis of thyroid cancer related to pregnancy: a systematic review.
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ABSTRACT: Differentiated thyroid cancer (DTC) is the second most common cancer in pregnancy. Its management is a challenge for both doctors and patients, and the best timing for surgery is unclear. A systematic review evaluating the prognosis of DTC in pregnant patients was conducted. After reviewing 401 unique citations and 54 full texts, 4 studies that compared the prognosis of patients with DTC related to pregnancy (DTC diagnosed during pregnancy or within 12 months after childbirth) or not were included. In two studies the primary outcome was overall survival, in one study the primary outcomes were recurrent disease and death related to thyroid cancer, and in one study the primary outcome was recurrent or persistent disease. In the first two studies, there was no difference in overall survival in patients with pregnancy-related DTC, when compared with matched controls; in one study, there was no difference in death caused by DTC nor recurrence in DTC related to pregnancy. Nevertheless, in a recent retrospective study, a higher rate of recurrent or persistent DTC was observed in patients with DTC related to pregnancy. There are not many studies on which to base treatment decisions in pregnant patients with DTC.Journal of thyroid research. 01/2011; 2011:691719. -
Article: Two weeks of a low-iodine diet are equivalent to 3 weeks for lowering urinary iodine and increasing thyroid radioactive iodine uptake.
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ABSTRACT: The importance of restricting iodine intake to increase thyroid uptake of ¹³¹I is well-known, but its minimum duration is not clear. The present study aimed at determining whether 3 weeks is superior to 2 weeks for a low-iodine diet (LID) as a means of increasing the thyroid uptake of ¹³¹I and reducing urinary iodine. A second goal was to evaluate the effectiveness of a questionnaire about ingestion and exposure to iodine to predict individuals in whom the LID would be less effective. Forty-six outpatients who came to the Nuclear Medicine Unit of Santa Casa de Porto Alegre, Brazil, for thyroid evaluation, were randomized to receive an LID for 2 or 3 weeks. Questionnaires regarding their exposure to iodine, the thyroid uptake of ¹³¹I, and the iodine and iodine/creatinine ratio in urine samples were administered or obtained at the beginning and end of the diet. The questionnaire indicated exposure to exogenous iodine in five patients during their LID, all in the 3-week group. Their thyroid ¹³¹I uptake was significantly lower than patients who did not give a history of iodine exposure (p = 0.016). The comparative analysis between the 2-week and 3-week diet groups was then performed excluding the five contaminated patients. The ¹³¹I uptake increased by 43% in the 2-week group and 26.7% in the 3-week group (p = 0.105). Both diets for 2 and 3 weeks caused significant decrease in urinary iodine (p < 0.001), without a difference between the groups (63.2% in the 2-week group and 60.9% in the 3-week group, p = 0.955). There was no difference in the percentage of patients with urinary iodine ≤100 μg/L (p = 0.25) and urinary iodine ≤50 μg/L (p = 0.86) between the groups. A correlation between urinary iodine and iodine/creatinine ratio (r = 0.516; p < 0.001) was observed. Two weeks of an LID are probably sufficient to augment thyroid uptake of ¹³¹I, with little or no benefit from longer periods of an LID. Questionnaires regarding exposure to iodine similar to those employed here should identify individuals in whom the LID has not been as effective in increasing the thyroid uptake of ¹³¹I.Thyroid: official journal of the American Thyroid Association 01/2011; 21(1):61-7. · 2.60 Impact Factor -
Article: Adrenal Failure due to Adrenal Metastasis of Lung Cancer: A Case Report.
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ABSTRACT: We report a case of a patient with adrenal failure due to bilateral adrenal metastasis of lung cancer. This is a rare presentation of lung cancer. We review the differential diagnosis of weight loss and how to make diagnosis of adrenal insufficiency.Case reports in oncological medicine. 01/2011; 2011:326815. -
Article: Could magnesium depletion play a role on fracture risk in PPI users?
Archives of internal medicine 10/2010; 170(19):1776. · 11.46 Impact Factor -
Article: Intra- and interindividual iodine excretion in 24 hours in individuals in southern Brazil: a cross-sectional study.
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ABSTRACT: To evaluate the variability of 24-hour urinary iodine (UI) excretion intra- and interindividually on three days of a week in healthy subjects, living in southern Brazil, and the correlation among the urinary excretion of iodine and sodium. Cross-sectional study, including 47 volunteers: 18 individuals with one, 15 individuals with two and 14 individuals with three 24-hour urine samples. Iodine, creatinine and Na(+) excretion in urine during 24-hour were measured. Mean height, weight, BMI and 24-hour urinary excretion of creatinine were higher in men. UI and urinary sodium were correlated (n = 89, r = 0.524, p = 0.000). UI excretion varied widely, both inter- and intraindividually, on the 3 days of the week, but the mean excretion of UI was similar. In single individuals, the ratio between the maximum and minimum 24-hour UI excretion (m/m) ranged from 1.03 to 2.87, and the median coefficient of variation (CV) was 21% (P₂₅ = 7.0% and P₇₅ = 36.8%), with a range of 1%-51%. 24-hour UI excretion varied greatly among individuals on Sunday (CV = 47.5% and m/m = 7.75), Monday (CV = 38.7% and m/m = 4.60) and Thursday (CV = 40.4% and m/m = 4.50). UI was adequate in the group of 14 people, however, the UI excretion of two women suggested iodine intake persistently below that recommended by WHO. The variability of 24-hour UI excretion on different days in the same individual is lower than that observed among individuals.Annals of Nutrition and Metabolism 01/2010; 57(3-4):260-4. · 2.26 Impact Factor -
Article: Secondary hyperparathyroidism is associated with increased risk of hospitalization or death in elderly adults living in a geriatric institution.
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ABSTRACT: The presence of secondary hyperparathyroidism is very frequent in the elderly population living in geriatric institutions. It has been associated with an increased mortality rate in previous studies. To evaluate the association of secondary hyperparathyroidism with mortality or hospitalization or both (combined outcome) during a 6-month period in individuals living in geriatric institutions. A cohort of 100 individuals aged between 65 and 102 years living in geriatric institutions in the city of Porto Alegre, Brazil, was prospectively studied. Serum levels of 25-hydroxyvitamin D [25(OH)D], parathyroid hormone (PTH), albumin, total calcium, phosphorus, magnesium, creatinine and alkaline phosphatase were measured. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault equation. Secondary hyperparathyroidism was defined as serum PTH levels higher than 48 pg/ml and normal or reduced serum calcium levels. The deaths were verified by means of death certificates and hospitalization by the discharge summaries provided by the Brazilian health system hospitals. Fifty-eight percent of the individuals had secondary hyperparathyroidism, defined as serum PTH >48 pg/ml and normal or low serum calcium. Mean serum 25(OH)D levels were 12.5 +/- 8 ng/ml. The odds ratio of an individual with secondary hyperparathyroidism to die, to be hospitalized or to have the combined outcome within 6 months was 6.6 [confidence interval (CI) 95% 0.8-54.6; p = 0.07], 10.7 (CI 95% 1.3-85.9; p = 0.007) and 5.20 (CI 95% 1.10-27.7; p = 0.04), respectively. Secondary hyperparathyroidism and body mass index were independently associated with the combined outcome, after correction for the GFR and 25(OH)D. Secondary hyperparathyroidism could be an important prognostic factor for individuals living in geriatric institutions.Gerontology 08/2009; 55(4):405-10. · 2.78 Impact Factor -
Article: Vitamin D2 could be one of the protective phytochemicals.
International Journal of Cancer 06/2009; 125(8):1994. · 5.44 Impact Factor -
Article: [Patients with hypovitaminosis D may not have secondary hyperparathyroidism].
Arquivos brasileiros de endocrinologia e metabologia 11/2008; 52(7):1202-3. · 0.68 Impact Factor -
Article: [Vitamin D deficiency in adults: to better understand a new presentation of an old disease].
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ABSTRACT: Vitamin D is synthesized in skin through a reaction mediated by sunlight, and it is metabolized to 25-hydroxyvitamin D, in liver, and in 1,25-dihydroxyvitamin D, in kidney. This last reaction has a tight feedback mechanism. 1,25-dihydroxyvitamin D is the active hormone, and its actions are mediated mainly by nuclear receptors. Its major functions are in calcium metabolism and bone mass maintenance. Hypovitaminosis D, as a disease in adult people, manifests itself with hypocalcemia and secondary hyperparathyroidism with subsequent loss of trabecular bone, thinning of cortical bone, and, eventually, a higher risk of fractures. Hypovitaminosis D is a very common condition in Europe, Africa, North America and some South American countries, such as Chile and Argentina. Measurement of serum total 25-hydroxyvitamin D concentration is the gold standard to diagnose vitamin D deficiency. Serum concentrations below 50 nmol/L are associated with an increase in parathyroid hormone concentration, and bone loss. Risk factors for vitamin D deficiency, like poor sunlight exposition, aging skin and factors that interfere with normal vitamin D metabolism, are well established. Oral vitamin D supplementation, an easy and inexpensive treatment, is needed to treat this illness.Arquivos Brasileiros de Endocrinologia & Metabologia 03/2006; 50(1):25-37. · 0.88 Impact Factor -
Article: Hyperparathyroidism secondary to hypovitaminosis D in hypoalbuminemic is less intense than in normoalbuminemic patients: a prevalence study in medical inpatients in southern Brazil.
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ABSTRACT: Hypovitaminosis D has been reported in tropical countries, but this hormone has seldom been studied in Brazil. Our purpose was to study the prevalence of hypovitaminosis D in patients hospitalized in internal medicine wards in Southern Brazil. Possible associated factors were studied. We studied 81 adult patients in early spring. Mean serum 25(OH)D was 12 +/- 8.57 ng/mL; hypovitaminosis D was severe (< 10 ng/mL) in 27 (33.3%) patients, and moderate (> or = 10 ng/mL and < 20 ng/mL) in 36 (44.5%) patients. Clinical evaluation did not yield any data associated with hypovitaminosis D. Serum 25(OH)D levels of up to 20 ng/mL were associated with decreased mean serum total calcium (p = 0.001), ionized calcium (p = 0.01), and phosphorus (p = 0.044) levels, and increased mean serum PTH level (p = 0.001). In a multiple regression model, serum PTH level was independently affected by serum total calcium (p = 0.01), phosphorus (p = 0.009), and albumin (p = 0.009) levels. Hypovitaminosis D patients had lower mean serum albumin levels (p = 0.004), and serum 25(OH)D levels were directly correlated to serum albumin levels (p < 0.0001). Albumin influenced independently PTH response to hypovitaminosis D; normoalbuminemic hypovitaminosis D patients had higher mean serum PTH than hypoalbuminemic patients. Conclusion: Hypovitaminosis D prevalence was very high in medical inpatients in Southern Brazil, in early spring. Nevertheless, secondary hyperparathyroidism was less intense in hypoalbuminemic hypovitaminosis D patients suggesting that in these patients free serum 25(OH)D was closer to normal.Endocrine 06/2004; 24(1):47-53. · 1.42 Impact Factor -
Article: [Cancer in thyroid nodules: evaluation of ultrasound and fine-needle aspiration biopsy].
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ABSTRACT: Thyroid nodules are a very common clinical problem and fine-needle aspiration biopsy (FNAB) is its main diagnostic test. Recently, it has been shown that some ultrasonographic features are associated to an increased risk of cancer, but a comparison between FNAB and ultrasonography (US) or its combination is not available. The aim of this study was to evaluate FNAB and US performance, isolated or combined, for cancer diagnosis in thyroid nodules. Eighty patients, with palpable solitary thyroid nodules or multinodular goiters, who were to undergo surgery, were selected among 289 patients seen in our clinic between March, 1995 and July, 1997. US and FNAB were performed by one of us. US was considered positive for cancer when microcalcifications, absent halo or hypoechogenicity were seen. FNAB was considered positive for cancer when it was either suspicious or compatible with malignancy. Both methods (FNAB and US) were evaluated in parallel combination (positive when FNAB or US was positive) and in serial combination (positive when both, FNAB and US, were positive). Sensitivity and specificity of FNAB and US for cancer diagnosis in thyroid nodules were, respectively, 87% and 62%, and 81% and 70%. Serial combination of FNA and US had sensitivity of 69% and specificity of 91%, and parallel combination resulted in sensitivity of 94% and specificity of 52%. The US had good accuracy in the evaluation of thyroid nodules, and can help us take some decisions in the clinical practice, supplementary to FNA. Nevertheless, the quality of the ultrasound examination depends on the experience of the examiner and on the characteristics of the equipment, so new studies are necessary to evaluate these factors to the current usage of ultrasonographic characteristics in the evaluation diagnostic of thyroid nodules.Revista da Associação Médica Brasileira 49(2):145-9. · 0.77 Impact Factor -
Article: Vitamin B12 in metformin-treated diabetic patients: a cross-sectional study in Brazil.
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ABSTRACT: The objective of this study was to evaluate the presence of vitamin B12 deficiency and the factors associated with serum vitamin B12 levels in a sample of metformin-treated Brazilian diabetic patients. Cross-sectional study. 144 patients were included. Serum vitamin B12 levels were low (< 125 pmol/L) in 10 patients (6.9%) and possibly low (125 - 250 pmol/L) in 53 patients (36.8%). Serum vitamin B12 levels were negatively associated with age (B = -3.17; β= -0.171; p = 0.037) and duration of metformin use (B= -33.36; β= -0.161; p = 0.048), and positively associated with the estimated intake of vitamin B12 (B= 67.96; β= 0.249; p = 0.002). The present findings suggest a high prevalence of vitamin B12 deficiency in metformin-treated diabetic patients. Older patients, patients in long term treatment with metformin and low vitamin B12 intake are probably more prone to this deficiency.Revista da Associação Médica Brasileira 57(1):46-9. · 0.77 Impact Factor -
Article: [Diagnosis of celiac disease in adults].
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ABSTRACT: Celiac disease (CD) is found in genetically predisposed individuals, and characterized by an intolerance to ingestion of gluten, contained in cereals such as barley, rye, wheat and malt. Clinical manifestations of CD vary from asymptomatic patients to severe forms of malabsorption syndromes, which may involve multiple systems and increase the risk of some malignancies. Diagnosis of CD requires a high degree of suspicion. There is no single test for the diagnosis, which is reached after a combination of clinical and laboratory data. The first step for diagnosis is a serum test such as tissue antitransglutaminase, antibodies or antiendomisio. If serum result is positive, prompt duodenal biopsy is necessary for diagnostic confirmation. An IgA deficiency, which occurs in 3% of patients with DC, may lead to false-negatives because serology is based on IgA. Another situation of false-negative tests is diet restriction of gluten; therefore diagnostic investigation must be carried out during a diet containing gluten. The screening for CD in asymptomatic individuals is not indicated.Revista da Associação Médica Brasileira 56(1):122-6. · 0.77 Impact Factor
Top co-authors
Top Journals
Institutions
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2006–2012
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Universidade Federal do Rio Grande do Sul
- Departamento de Medicina Interna
Porto Alegre, Estado do Rio Grande do Sul, Brazil
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2011
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Hospital Nossa Senhora da Conceição
Tubarão, Estado de Santa Catarina, Brazil
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2004–2011
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Hospital De Clínicas De Porto Alegre
Porto Alegre, Estado do Rio Grande do Sul, Brazil
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