Renan Magalhães Montenegro Júnior

Universidade Federal do Ceará, Ceará, Ceará, Brazil

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Publications (42)21.1 Total impact

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    ABSTRACT: Objective: To evaluate the effect of sitagliptin on somatosensory-evoked potentials (SEPs) and metabolic control in patients with type 2 diabetes mellitus without clinical diabetic neuropathy. Materials and methods: Interventional, prospective, and open study. Patients with less than six months from the diagnosis were included. Examinations of SEPs and laboratory tests at fasting and after food stimulation were performed before and after three months of treatment with sitagliptin (100 mg/day). Results: There was a reduction in the mean levels of HbA1c (P < 0.0001), fasting glucose (P = 0.001), total cholesterol (P = 0.019), and ALT (P = 0.022). An increase in active GLP-1 was found at the end of the study (P = 0.0025). Several SEPs showed statistically significant differences when analyzed before and after treatment with sitagliptin. Conclusion: The results give a glimpse of the possible use of sitagliptin in the treatment of some neurodegenerative conditions of the peripheral nervous system, in addition to its already established role in glycemic control.
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    ABSTRACT: To evaluate the determinants of intensive insulin regimens (ITs) in patients with type 1 diabetes (T1D).
    Diabetology and Metabolic Syndrome 05/2014; 6:67. DOI:10.1186/1758-5996-6-67
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    ABSTRACT: OBJECTIVE: The objective of this study is to investigate the influence of the day-to-day variability of the measures of heart rate variability (HRV) on the sample size calculation for the study of cardiac autonomic neuropathy. MATERIAL AND METHODS: We analyzed HRV in the frequency domain [very low (VLF), low (LF), and high frequency (HF) bands] and in the time domain [the root mean squared of successive RR intervals differences (RMSSD); the mean RR intervals (RRNN); the standard deviation of RR intervals (SDNN) and the coefficient of variation (CV)] during a 5-min electrocardiogram record. We also analyzed the heart rate response to deep breathing [expiration:inspiration ratio], to the Valsalva maneuver and to standing [maximum:minimum ratio] and the blood pressure response to standing. The day-to-day variability was assessed by calculating the within-subject standard deviations (WSSD), limits of agreement, typical errors and the ratio of the WSSD to the mean values obtained on days 1 and 2 (WSSD/GM). RESULTS: Sixty-seven healthy subjects (45 females), aged 27 (19-39) years, were recruited. The RMSSD, CV, VLF, LF, HF and blood pressure response to standing showed marked variability (WSDD/GM (%)=237.7, 455.1, 69.9, 126.5, 81.3 and 380.5, respectively), while the RRNN, SDNN, Valsalva, expiration:inspiration and maximum:minimum ratio showed less variability (WSSD/GM (%)=6.4, 24.5, 18.6, 11.0 and 14.1, respectively). The minimum differences expected to be statistically significant for the autonomic measurements were calculated. CONCLUSION: Some tests that assess HRV showed adequate reproducibility. This study allows the determination of a sample size calculation for longitudinal or drug-testing studies.
    Autonomic neuroscience: basic & clinical 10/2013; 177(2):275-279. DOI:10.1016/j.autneu.2013.05.444
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    ABSTRACT: To examine excessive daytime sleepiness (EDS) in type 2 diabetes. Patients (N = 110) were evaluated regarding Epworth Sleepiness Scale (EDS), sleep quality (Pittsburgh Sleep Quality Index), depressive symptoms (Beck Depression Inventory), Restless Legs Syndrome (RLS), risk of obstructive sleep apnea (OSA) (Berlin questionnaire), and comorbidity severity (Charlson Comorbidity Index). Patients were compared with indivi-duals with arterial hypertension and without diabetes. Diabetic patients had more EDS, depressive symptoms, and higher comorbidity severity than hypertensive patients (p < 0.005). In diabetic patients, poor quality sleep (53.3%), and high risk of OSA (40.9%) and RLS (14.5%) were found; EDS (55.5%) was associated with depressive symptoms present in 44.5% indivi-duals (OR = 1.08; 95% CI: 1.01-1.15), and remained so after data were controlled for age, gender, body mass index, and glycated hemoglobin (OR = 2.27; 95% CI 1.03-5.03). Sleep abnormalities are frequent. EDS affects most of the patients and is independently associated with depressive symptoms. Adequate antidepressant therapy should be tested for the effects on EDS.
    Arquivos brasileiros de endocrinologia e metabologia 08/2013; 57(6):425-30. DOI:10.1590/S0004-27302013000600003
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    ABSTRACT: INTRODUCTION: Subclinical hypothyroidism (SCH), defined as elevated concentrations of thyroid stimulating hormone (TSH) despite normal levels of thyroid hormones, is highly prevalent in Brazil, especially among women and the elderly. Although an increasing number of studies have related SCH to an increased risk of coronary artery disease and mortality, there have been no randomized clinical trials verifying the benefit of levothyroxine treatment in reducing these risks, and the treatment remains controversial. OBJECTIVE: This consensus, sponsored by the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism and developed by Brazilian experts with extensive clinical experience with thyroid diseases, presents these recommendations based on evidence for the clinical management of SCH patients in Brazil. MATERIALS AND METHODS: After structuring the clinical questions, the search for evidence in the literature was initially performed in the MedLine-PubMed database and later in the Embase and SciELO - Lilacs databases. The strength of evidence was evaluated according to the Oxford classification system and established based on the experimental design used, considering the best available evidence for each question and the Brazilian experience. RESULTS: The topics covered included SCH definition and diagnosis, natural history, clinical significance, treatment and pregnancy, and the consensus issued 29 recommendations for the clinical management of adult patients with SCH. CONCLUSION: Treatment with levothyroxine was recommended for all patients with persistent SCH with serum TSH values > 10 mU/L and for certain patient subgroups.
    Arquivos brasileiros de endocrinologia e metabologia 04/2013; 57(3):166-183.
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    ABSTRACT: INTRODUÇÃO: O hipotireoidismo subclínico (HSC), definido por concentrações elevadas do TSH em face de níveis normais dos hormônios tireoidianos, tem elevada prevalência no Brasil, particularmente entre mulheres e idosos. Embora um número crescente de estudos venha associando o HSC com maior risco de doença arterial coronariana e de mortalidade, não há ensaio clínico randomizado sobre o benefício do tratamento com levotiroxina na redução dos riscos e o tratamento permanece controverso. OBJETIVO: Este consenso, patrocinado pelo Departamento de Tireoide da Sociedade Brasileira de Endocrinologia e Metabologia e desenvolvido por especialistas brasileiros com vasta experiência clínica em tireoide, apresenta recomendações baseadas em evidências para uma abordagem clínica do paciente com HSC no Brasil. MATERIAIS E MÉTODOS: Após estruturação das questões clínicas, a busca das evidências disponíveis na literatura foi realizada inicialmente na base de dados do MedLine-PubMed e posteriormente nas bases Embase e SciELO - Lilacs. A força da evidência, avaliada pelo sistema de classificação de Oxford, foi estabelecida a partir do desenho de estudo utilizado, considerando-se a melhor evidência disponível para cada questão e a experiência brasileira. RESULTADOS: Os temas abordados foram definição e diagnóstico, história natural, significado clínico, tratamento e gestação, que resultaram em 29 recomendações para a abordagem clínica do paciente adulto com HSC. CONCLUSÃO: O tratamento com levotiroxina foi recomendado para todos os pacientes com HSC persistente com níveis séricos do TSH > 10 mU/L e para alguns subgrupos especiais de pacientes.
    Arquivos Brasileiros de Endocrinologia & Metabologia 03/2013; DOI:10.1590/S0004-27302013000300003
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    ABSTRACT: This study aimed to verify the impact of levothyroxine replacement on health-related quality of life (HRQoL) in a Brazilian sample of primary hypothyroidism patients. A cross-sectional study was performed with 2,057 consecutive primary hypothyroidism patients on levothyroxine (LT4) replacement at four referral centers in Brazil (median age = 53; 25th percentile = 43; 75th percentile = 61 years). Patient biochemical data were acquired from medical records, and patients completed a questionnaire on socioeconomic issues and clinical signs and symptoms of hypothyroidism. HRQoL was assessed using the SF-36v2. Patients were divided into three groups according to TSH levels: overtreated (OvT; TSH < 0.4 mU/L), appropriately treated (AT; TSH between 0.4 and 4.0 mU/L), and undertreated (UnT; TSH > 4.0 mU/L). Patients were also analyzed by TSH and FT4 serum levels: overt hyperthyroidism (OHyper; TSH < 0.4 mU/L and FT4 > 1.9 ng/dL), subclinical hyperthyroidism (SHyper; TSH < 0.4 mU/L and FT4 0.8-1.9 ng/dL), subclinical hypothyroidism (SHypo; TSH > 4.0 mU/L and FT4 0.8-1.9 ng/dL), and overt hypothyroidism (OHypo; TSH > 4.0 mU/L and FT4 < 0.8 ng/dL). A total of 14.4 % of patients were OvT, with 13.0 % SHyper and 1.4 % OHyper. The prevalence of UnT was 25.9 %, with 21.5 % SHypo and 4.4 % OHypo. Overtreatment was not associated with HRQoL impairment. UnT patients had worse HRQoL than AT patients, especially for physical and emotional aspects, independent of SHypo or OHypo status. Hypothyroidism undertreatment is associated with poor patient HRQoL. Therefore, adequate LT4 therapy should be given to maintain serum TSH within the reference range.
    Endocrine 01/2013; 44(2). DOI:10.1007/s12020-013-9886-1
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    ABSTRACT: Pregnancy affects both maternal and fetal metabolism, and even in non-diabetic women, it exerts a diabetogenic effect. Among pregnant women, 2% to 14% develop gestational diabetes. Pregnancy can also occur in women with preexisting diabetes, which may predispose the fetus to many alterations in organogenesis, restrict growth, and the mother, to some diabetes-related complications, such as retinopathy and nephropathy, or to acceleration of the course of these complications, if they are already present. Women with gestational diabetes generally start their treatment with diet and lifestyle changes; when these changes are not enough for optimal glycemic control, insulin therapy must then be considered. Women with type 2 diabetes using oral hypoglycemic agents are advised to change to insulin therapy. Those with preexisting type 1 diabetes should start intensive glycemic control. As basal insulin analogues have frequently been used off-label in pregnant women, there is a need to evaluate their safety and efficacy. The aim of this review is to report the use of both short- and long-acting insulin analogues during pregnancy and to enable clinicians, obstetricians, and endocrinologists to choose the best insulin treatment for their patients.
    Arquivos brasileiros de endocrinologia e metabologia 10/2012; 56(7):405-14.
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    ABSTRACT: Acromegaly is a rare endocrine disease. Few studies have evaluated its association with hearing loss (HL) and the results are conflicting. To evaluate the prevalence and features of HL in a group of patients being treated for acromegaly. To analyze peripheral and central auditory transmission. Cross-sectional study. A group of 34 patients with acromegaly were submitted to metabolic evaluation, tonal audiometry and brainstem auditory evoked potentials. HL was considered when pure tone average was > 25 DBHL for low frequencies (250, 500, 1000 and 2000 Hz) or high frequencies (3000, 4000, 6000 and 8000 Hz). The patients were divided in group A (with HL) and B (without HL). Twelve patients (35.3%) had sensorineural HL (Group A), being 8 bilateral and 4 unilateral. No one had mixed or conductive HL. The prevalence of diabetes/impaired glucose tolerance was similar between the groups. The frequencies 3000, 4000, 6000 and 8000 Hz were the most affected and with a similar pattern in both ears. sensorineural HL was found in 38.9% of cases. Neither clinical nor metabolic differences were noted between the groups, as well as in regards to peripheral and central auditory transmission.
    Brazilian journal of otorhinolaryngology 08/2012; 78(4):98-102. DOI:10.1590/S1808-86942012000400018
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    ABSTRACT: The objectives of this study are to estimate the prevalence of arterial hypertension (AH) in an adult population with a predominance of families with low education and income levels, in the hinterlands of Pernambuco, Brazil, and to analyze its association with other factors related to cardiovascular diseases (CVD). A cross-sectional study in 2008/2009 was conducted with a sample of 198 subjects stratified by age, and representative of the urban adult population of the Canaã district of city of Triunfo, in the hinterlands of Pernambuco, Brazil. One hundred ninety eight individuals with average age of 57.7 years old (31 to 90 years-old), mainly women (65.6%), and with low income and education levels (81.3% with a monthly income of less than one minimum wage) were evaluated. Among these, 127 (64.1%) were identified as having AH, 54 (42.5%) of whom had no prior diagnosis. From those who were previously diagnosed, only 31.3% had good blood pressure control. Higher prevalence was observed in those individuals with lower incomes, higher body mass indexes (BMI), and those with metabolic syndrome (MS). These data demonstrated that there was a high prevalence of AH in the urban, low education and income levels adult population of Triunfo, strongly associated with lower income levels, elevated BMI, and the presence of MS; and a high prevalence of bad blood pressure control among the previously diagnosed cases. These results indicate that more effective interventions for early detection and adequate control of this disease and its comorbidities are necessary.
    Revista da Associação Médica Brasileira 04/2012; 58(2):209-14. DOI:10.1590/S0104-42302012000200017
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    ABSTRACT: To determine the prevalence of patients with type 1 diabetes mellitus who meet the glycemic and cardiovascular (CV) risk factors goals and the frequency of screening for diabetic complications in Brazil according to the American Diabetes Association guidelines. This was a cross-sectional, multicenter study conducted between December 2008 and December 2010 in 28 public clinics in 20 Brazilian cities. Data were obtained from 1774 adult patients (56.8% females, 57.2% Caucasians) aged 30.3 ± 9.8 years with diabetes duration of 14.3 ± 8.8 years. Systolic blood pressure was at goal in 40.3% and diastolic blood pressure was at goal in 26.6% of hypertensive patients. LDL cholesterol and HbA1c were at the goal in 45.2% and 13.2% of the patients, respectively. Overweight was presented in 25.6% and obesity in 6.9%. Among those with more than 5 years of disease, screening for retinopathy was performed in the preceding year in 70.1%. Nephropathy and feet complications were screened in 63.1% and 65.1%, respectively. The majority of patients did not meet metabolic control goals and a substantial proportion was not screened for diabetic complications. These issues may increase the risk of chronic complications and negatively impact public health.
    Diabetes research and clinical practice 03/2012; 97(1):63-70. DOI:10.1016/j.diabres.2012.02.008
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    ABSTRACT: Renal complications in acromegaly include glomerular hyperfiltration, insulin resistance, hypercalciuria and urolithiasis. The aim of this study was to investigate whether urinary calcium (U(Ca)) excretion is a direct consequence of growth hormone secretion or secondary to hyperfiltration and/or insulin resistance. We performed a cross-sectional study of 58 patients diagnosed with acromegaly. Demographic data were obtained, serum analysis was performed, including insulin-like growth factor (IGF)-1, and 24-h urine collection, to measure urinary protein excretion, U(Ca) and phosphate excretion, as well as fractional excretion of sodium and potassium. We also calculated the homeostasis model assessment of insulin resistance (HOMA-IR). Patients were predominantly male (60.3%), and their mean age was 45.9 ± 14 years. Hypercalciuria was present in 24% of patients. Patients with higher HOMA-IR had higher IGF-1 levels, a trend toward higher body mass index and higher U(Ca) excretion. In univariate analysis, U(Ca) excretion was associated with HOMA-IR (r = 0.472, P = 0.001), phosphaturia (r = 0.457, P = 0.001), IGF-1 (r = 0.398, P = 0.002) and creatinine clearance (r = 0.394, P = 0.001). HOMA-IR and phosphaturia were independently associated with U(Ca) excretion. No independent associations were found between phosphaturia and HOMA-IR or IGF-1. The present study revealed an association between hypercalciuria and insulin resistance in patients with acromegaly. Further studies are required to fully understand the pathogenesis of these abnormalities in patients with acromegaly.
    International Urology and Nephrology 01/2012; 44(5):1473-7. DOI:10.1007/s11255-011-0116-6
  • 01/2011; 12(4). DOI:10.5007/1980-0037.2010v12n4p262
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    ABSTRACT: The gradual and progressive replacement of infectious and parasitic by chronic diseases as causes of morbidity and mortality, characterizing the process of epidemiological transition hasn't been observed in various populations, especially in underdeveloped or developing countries characterizing a superposition of these profiles (incomplete transition). Besides the increased prevalence of metabolic disorders, various infectious diseases remain endemic in several regions, such as leprosy, tuberculosis, leishmaniasis, viral hepatitis, among others, as well as emerging diseases in recent decades, as HIV infection/Aids. In this context, more attention has been given to the occurrence of metabolic disturbances in the recent years, mainly from the observation of a high incidence of metabolic disorders associated with HIV infection/Aids, and its therapy with antiretroviral drugs. This review addresses clinical and epidemiological aspects of metabolic disturbances reported in some infectious and parasitic diseases with worldwide and local (Brazil) relevance, as well as possible mechanisms and factors involved in these associations.
    Arquivos brasileiros de endocrinologia e metabologia 12/2010; 54(9):785-92. DOI:10.1590/S0004-27302010000900003
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    Arquivos Brasileiros de Endocrinologia & Metabologia 01/2010; 54(1). DOI:10.1590/S0004-27302010000100003
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    ABSTRACT: Objectives: To describe the microbiological profile and clinical outcomes of diabetic foot ulcers of inpatients of a tertiary university hospital, at Ceara, Brazil. Methods: We conducted a retrospective analysis of medical charts data of all diabetic inpatients of the Endocrine and Diabetes Unit of Walter Cantídio University Hospital (Federal University of Ceará), admitted from January, 2006 to June, 2007 for severe foot ulcers (minimum of grade 2 of Wagner`s classification), which were refractory to ambulatory treatment. Clinical data from each patient were recorded (sex, age, diabetes duration, and comorbidities) as well as microbiological characteristics of foot ulcers and surgical (amputations) material. Results: We identified 17 diabetic patients, all type 2, aged 58.11 ± 10.8 years and 12.4 ± 8.4 years of disease, 58.8% male. Of ulcers, 41.1% were grade 2; 35.2% grade 3; 11.7% grade 4 and 11.7% grade 5 of Wagner; 64.7% with less than 3 months of evolution. Debridement was performed in 82.3% of patients and amputation in 47%; osteomyelitis was identified in 47% of cases. All patients started empiric antibiotic therapy, where ciprofloxacin/metronidazole was the most used scheme (76.5%). Cultures were negative in 12.5% of the patients. In the positive ones, the most prevalent bacterial pathogens detected in the culture materials were: S. aureus (57.1%); S. viridans (28.7%); P. aeruginosas (28.7%); M. morganii (28.7%). The majority (75%) of isolated S. aureus were methicillin-resistant, but were sensitive to vacomicin. Conclusion: We observed the presence of polymicrobial flora with a large number of multiresistant pathogens and high prevalence of osteomyelitis and amputations in diabetic patients with severe ulcers, neuropathy and peripheral vascular disease.
    01/2010; 23(3):231-236. DOI:10.5020/18061230.2010.p231
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    ABSTRACT: Arterial hypertension is one of the main risk factors for the development of cardiovasculardiseases and affects a substantial part of the Brazilian population. The objective ofthis study was to compare the level of knowledge between Physical Education Professionals whoworked with hypertensive students in gyms and those who did not. A total of 400 professionalsworking in gyms in the Municipality of Fortaleza-CE participated in the study. A questionnairecontaining the following information was used: knowledge about criteria for hypertension, typesof laboratory tests, types of hypertension in the students, general care during physical activity, andrecommendations for a better control of hypertension. Among the 400 professionals, 302 (75.5%)worked with hypertensive students. Of these, 236 (59%) based their diagnosis of hypertensionsolely on the report of the students. Regarding the situations in which the professionals contraindicatedphysical activity for the hypertensive students, 43.1% reported high blood pressure, 15.5%reported no situation, and 21.5% had no information. With respect o blood pressure measurementbefore and after physical activity, most of the professionals (62.3%) working with hypertensivestudents did not measure the student’s blood pressure. The knowledge of the professionals abouthypertension in gyms was insufficient. More specific studies are necessary to obtain data thatwill contribute to the development of programs designed for Physical Education Professionalsthat establish the needs of hypertensive students in gyms.
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    01/2009; DOI:10.5020/18061230.2009.p41
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    ABSTRACT: Objective: To evaluate the hearing function of children with congenital hypothyroidism (CH). Methods: A descriptive, quantitative, cross-sectional study carried out at NAMI in Fortaleza University, on 2006. Forty six children joined in the study, of whom 30 children with CH receiving hormonal replacement therapy with levothyroxine and 16 healthy children consisting of control group (CG). All the children had an auditory evaluation. The control group children were submitted to a TSH and free T4 level. Medical records were analyzed to determine the TSH and free T4 level, the beginning and the follow-up for children with CH. Results: Female gender prevailed in both groups, CH and CG, 23 (76.7%) and 9 (56.3%) children, respectively. The age group of the children with CH ranged from 3 months to 8 years old and the age group of the children from CG ranged from 4 months to 5.6 years old. The average for the beginning of the therapy with levothyroxine in CH children was 135.43 ±325.58 days. The other auditory tests were within the normal range and no statistically significant difference was found between the groups. Conclusions: Children with CH didn’t show any alteration in hearing threshold levels. They were first submitted to an auditory exam very late and the average time to start the therapy for CH was 4.5 months. This could contribute for the absence of hearing alterations at auditory evaluations, indicating that treated congenital hypothyroidism, even though not precociously, will not cause alteration in hearing threshold levels.
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    ABSTRACT: To report the clinical and molecular aspects of a patient with a diagnosis of Resistance to Thyroid Hormone (RTH) harboring the E449X mutation associated with autoimmune thyroid disease and severe neuropsychomotor retardation. We present a case report including clinical and laboratory findings, and molecular analysis of a Brazilian patient with RTH. A 23-year old male presented hyperactivity disorder, attention deficit, delayed neuropsychomotor development, and goiter. Since the age of 1 year and 8 months, his mother had sought medical care for her son for the investigation of delayed neuropsychomotor development associated with irritability, aggressiveness, recurrent headache, profuse sudoresis, intermittent diarrhea, polyphagia, goiter, and low weight. Laboratory tests revealed normal TSH, increased T3, T4, antithyroglobulin and antimicrosomal antibody titers. Increasing doses of levothyroxine were prescribed, reaching 200 microg/day, without significant changes in his clinical-laboratory picture. Increasing doses of tiratricol were introduced, with a clear clinical improvement of aggressiveness, hyperactivity, tremor of the extremities, and greater weight gain. Molecular study revealed a nonsense mutation in exon 10, in which a substitution of a guanine to tyrosine in nucleotide 1345 (codon 449) generates the stop codon TAA, confirming the diagnosis of RTH. This patient has severe neuropsychomotor retardation not observed in a single previous report with the same mutation. This may reflect the lack of a genotype-phenotype correlation in affected cases with this syndrome, suggesting that genetic variability of factors other than beta receptor of thyroid hormone (TRbeta) might modulate the phenotype of RTH.
    Arquivos brasileiros de endocrinologia e metabologia 12/2008; 52(8):1205-10.