[Analysis of BRAF and NRAS mutations in thyroid tumors in patients from Argentina].

Introduction: Molecular alterations in follicular cells in the BRAF or NRAS genes have been reported to be associated with the process of carcinogenesis. Our aim was to determine the mutational frequency of BRAF and NRAS in fine-needle aspiration (FNA) specimens in our population.

Methods: The mutational status of BRAF (codon 600) and NRAS (codon 61) was analysed by qPCR in 193 FNA specimens from suspicious nodules and compared with pathological data of 115 patients.

Comparison between two newborn screening strategies for cystic fibrosis in Argentina: IRT/IRT versus IRT/PAP.

Background: The benefits of early cystic fibrosis (CF) detection using newborn screening (NBS) has led to widespread use in NBS programs. Since 2002, a two-stage immunoreactive trypsinogen (IRT/IRT) screening strategy has been used as a CFNBS method in all public maternity units in the City of Buenos Aires, Argentina. However, novel screening strategies may be more efficient.

Improving arylsulfatase activity determination in dried blood spots: Screening and diagnostic approaches for Maroteaux-Lamy syndrome (MPS VI).

Background: Mucopolysaccharidosis type VI can be screened by measuring the lysosomal arylsulfatase B (ARSB) residual enzyme activity in dried blood spots (DBS) using synthetic substrates. However, we have found experimental obstacles when determining ARSB activity with the fluorescent method due to the significant quenching effect rendered by DBS components.

Methods: We adapted the methods originally described by Chamoles et al.

Association between vitamin D and Apo B concentrations in Argentinean Indian children.

Objective: The objective of the study was to determine the prevalence of vitamin D insufficiency and its association with non-traditional cardiovascular disease (CVD) risk factors such as Apo B in South American Indian school children.

Methods: A cross-sectional study of 355 children (166 Males) aged 9.6±2.

Low vitamin D concentrations among indigenous Argentinean children living at high altitudes.

Background: Hypovitaminosis D is an international problem; however, there is little information about its prevalence in apparently healthy Indian children living at high altitudes.

Objectives: To determine (i) the prevalence of hypovitaminosis D and (ii) the association of serum vitamin D with the risk factors for diabetes among Indian Koya children.

Methods: A cross-sectional study of 290 (129 males) school children aged 10.

Association of vitamin D with glucose levels in indigenous and mixed population Argentinean boys.

Introduction: There is little information about low vitamin D concentrations in apparently healthy indigenous children in South America.

Objectives: (a) To compare the prevalence of hypovitaminosis D in SAC (San Antonio de los Cobres) versus BA (Buenos Aires) boys and (b) to determine the association of serum vitamin D concentration with age, gender, and risk factors for diabetes.

Methods: This cross-sectional study compares 129 boys from SAC with a 98% indigenous population, versus 116 boys from BA with a mixed population.

Dyslipidemia without obesity in indigenous Argentinean children living at high altitude.

Objectives: To compare the prevalence of cardiovascular disease risk factors in Indian children from San Antonio de los Cobres (SAC) and children from Buenos Aires (BA), and to examine body mass index (BMI), waist circumference (WC), and WC/height as predictors of dyslipidemia in both groups.

Study Design: Data were collected cross-sectionally from BMI, WC, blood pressure, Tanner scale, glucose, lipids, and insulin. Dyslipidemia was defined by the National Cholesterol Education Program and American Heart Association.

Lifestyle behaviors and dyslipidemia in Argentinean native versus urban children.

Objective: To determine the prevalence and distribution of dyslipidemia among urban children from Buenos Aires (BA) versus Koya Indian from San Antonio de los Cobres (SAC).

Design And Methods: Anthropometric measures, blood pressure, Tanner stages, glucose, lipids and insulin were measured. Dyslipidemia was defined by the NCEP (the National Cholesterol Education Program standards) and AHA (American Heart Association) criteria.

Association of lipoprotein-associated phospholipase A₂ activity with components of the metabolic syndrome in apparently healthy boys.

Background: Lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) has been proposed as a biomarker of risk of cardiovascular disease (CVD).

Objective: To determine the association between Lp-PLA(2) activity and BMI, insulin-resistance, components of the metabolic syndrome (MS), and lifestyle behaviors in healthy adolescent boys.

Methods: Data were collected cross-sectionally from 164 adolescents from an amateur rugby club.

Impact of unhealthy lifestyle behaviors and obesity on cholesteryl ester transfer protein among adolescent males.

Background And Aims: Cholesteryl ester transfer protein (CETP) has been proposed to be associated with high risk of cardiovascular disease. Increased CETP activity was previously reported in obese adults, although its association with lifestyle behaviors has not been assessed in healthy adolescents. We undertook this study to determine the association between CETP activity and overweight/obesity, insulin resistance markers, components of the metabolic syndrome and lifestyle behaviors in healthy adolescent males.

Comparison of different anthropometric indices for identifying dyslipidemia in school children.

Background: Anthropometric indices have been associated with dyslipidemia.

Objective: To compare the abilities of BMI, waist circumference (WC) and WC/height to identify children's dyslipidemia.

Methods: Students 1261 (639 male) age 9.

Tall stature without growth hormone: four male patients with aromatase deficiency.

Context: From preliminary observations, GH-IGF-I seems to be compromised in men with aromatase deficiency. The GH deficiency (GHD) coexists paradoxically with tall stature, raising the question whether or not a true GHD is part of this rare syndrome.

Objective: To evaluate the GH secretion in aromatase-deficient men, their GH response to the GHRH plus arginine (GHRH-ARG) test was compared with that of normal subjects.

Is albuminuria associated with obesity in school children?

Background: Different studies in adults have shown that obesity is an independent risk factor for end-stage renal disease.

Objective: It was to (i) determine the association between albuminuria and age, gender, BMI, waist circumference (WC), and blood pressure (ii) relate albuminuria to gender and age in healthy school children.

Methods: Over 1564 students (806 males) aged 9.

Relationship between obesity and metabolic syndrome among Argentinean elementary school children.

Background: Argentina has experienced marked increases in the prevalence of childhood overweight (OW)/obesity over the last few decades.

Objectives: We examined (1) the distribution of the mean values of lipids, glucose, and HOMA-IR according to the presence of OW/obesity, age, and sex and (2) the association between metabolic syndrome and OW/obesity, Tanner stage, gender, and HOMA-IR.

Methods: Data were collected from 1009 children (508 males) in 10 elementary schools between April and September 2007.

Chromogranin A as a biochemical marker for the management of neuroendocrine tumors: a multicenter study developed in Argentina.

Elevated circulating levels of chromogranin A (CgA) are found in the neuroendocrine tumors (NETs), but diagnostic usefulness of this marker is still debatable. To assess the role of CgA for the identification and follow up of gastroenteropancreatic neuroendocrine tumors (GEP-NET), a multicenter prospective longitudinal study has been carried out in Argentina. CgA was measured by RIA in 119 histologically proven GEP-NET patients and in 39 healthy controls.

Association between school children's overweight and maternal obesity and perception of their children's weight status.

Aim: To determine the association between overweight children and a) other components of the mothers' metabolic syndrome, such as body mass index (BMI), waist circumference (WC), HDL-cholesterol, triglycerides, glucose, HOMA-IR, blood pressure (BP), and age; and b) the mothers' perception of their children's overweight.

Methods: Six hundred and twenty children (297 M) aged 9 +/- 2 years and their mothers aged 37.7 +/- 7 years were examined between April and August 2006.

Maternal waist circumference and the prediction of children's metabolic syndrome.

Objective: To determine the association between metabolic syndrome (MS) components in 620 children and their mothers.

Design: Cross-sectional assessment.

Setting: Three public elementary schools in Buenos Aires, Argentina.

Can the metabolic syndrome identify children with insulin resistance?

Objective: The metabolic syndrome is associated with insulin resistance in adults. We defined pediatric metabolic syndrome using criteria analogous to Adult Treatment Panel III. The purpose of this study was to determine whether these criteria are reliable for insulin resistance in children.

A novel compound heterozygous mutation of the aromatase gene in an adult man: reinforced evidence on the relationship between congenital oestrogen deficiency, adiposity and the metabolic syndrome.

Background: Descriptions of new cases of human aromatase deficiency are useful for a better understanding of male oestrogen pathophysiology, as some aspects remain controversial.

Objective: To present a new case of an adult man affected by aromatase deficiency, along with a description of clinical phenotype, and hormonal and genetic analysis.

Design: Case report study.

Waist circumference identifies primary school children with metabolic syndrome abnormalities.

Objective: This study was designed to assess whether waist circumference can predict metabolic syndrome abnormalities in primary schoolchildren.

Research Design And Methods: Of 5,103 children (2,526 males) 4-13 years old who underwent anthropometric measurements, 530 had more extensive testing. Body mass index (BMI), waist circumference, and blood pressure were determined in all subjects.

Skeletal effects of long-term estrogen and testosterone replacement treatment in a man with congenital aromatase deficiency: evidences of a priming effect of estrogen for sex steroids action on bone.

The relative contribution of each sex steroid (i.e. estrogen and androgen) on bone in men and the relationships among sex steroids and changes in BMD and bone strength are still unknown.

Hypothalamic-pituitary-gonadal axis in two men with aromatase deficiency: evidence that circulating estrogens are required at the hypothalamic level for the integrity of gonadotropin negative feedback.

Background: In men, the feedback of gonadotropins is regulated by estrogens that come from the aromatization of testosterone, but the relative contribution to the inhibition of LH and FSH secretion by the amount of locally produced estrogens within the hypothalamus and/or the pituitary, and the amount of circulating estrogens still remains unknown.

Objective: In order to evaluate the effect of regulation induced by estradiol on the hypothalamic-pituitary-gonadal (HPG) axis, we studied the pulsatility of LH and FSH in two aromatase-deficient men (called subject 1 and subject 2), in which the production rate of estrogen (both local and circulating) is completely, or at least severely, impaired.

Design: FSH and LH were evaluated in terms of their pulsated secretion and as GnRH-stimulated secretion in two phases: phase 1, before estrogen treatment; and phase 2, during estrogen treatment with 25 microg transdermal estradiol twice weekly.

Can waist circumference identify children with the metabolic syndrome?

Objective: To determine in children the association between waist circumference (WC) and insulin resistance determined by homeostasis modeling (HOMA-IR) and proinsulinemia and components of the metabolic syndrome, including lipid profile and blood pressure (BP).

Methods: Eighty-four students (40 boys) aged 6 to 13 years and matched for sex and age underwent anthropometric measurements; 40 were obese; 28, overweight; and 16, nonobese. Body mass index (BMI), WC, BP, and Tanner stage were determined.