Erythrocyte zinc and serum copper in male and female adolescents according to puberty stage at different growth phases

BACKGROUND: Considering that modification in body composition and growth velocity leads to alterations in zinc and copper nutritional status, the purpose of the study was to assess erythrocyte zinc and serum copper in adolescents of both genders, according to the stage of sexual maturity at different growth phases. METHODS: Two hundred and eighty-six adolescents were assessed, 157 were female, with body mass index Z-scorebetween−2 and +2. Clinical biochemical measurements were assessed using atomic absorption spectrophotometry. Student's t, Kruskal-Wallis, and Bonferroni tests were used. RESULTS Median serum copper was superior, and zinc was inferior to respective reference values in all groups. Serum copper presented significant reduction in the final stages of pubertal development in males; in turn, erythrocyte zinc values increased linearly with the evolution of puberty stages in both genders. Comparison between genders in each stage of growth showed significant difference in peak acceleration and in deceleration for erythrocyte zinc and serum copper, with both being higher in females. CONCLUSIONS: Serum copper is inversely influenced by modifications that occur with the evolution of puberty in males, whereas erythrocyte zinc is directly influenced in both genders, although always with deficient deposition. At peak acceleration and deceleration of growth, there is greater mobilization of erythrocyte zinc and serum copper in males, when compared with females, which does not occur at the onset of the acceleration of growth.

Avaliação do hiperinsulinismo em amostra de crianças pré-puberes / Hyperinsulinism assessment in a sample of prepubescent children

OBJETIVOS: Determinar a relação entre o índice de massa corporal (IMC), o homeostasis model assessment - insulin resistance (HOMA-IR) e a insulinemia. MÉTODOS: Realizou-se um estudo observacional prospectivo transversal com 132 crianças pré-púberes em idade escolar e residentes no município de Santo André (SP). Fez-se a avaliação antropométrica e a mensuração da glicemia, da insulinemia e do índice HOMA-IR. RESULTADOS: Dentre as 132 crianças avaliadas, 78 eram meninas (59,1 por cento) e 54 eram meninos (40,9 por cento), com média de idade de 8,7 anos e média de IMC de 13,7 kg/m². Observou-se uma associação significativa e positiva entre HOMA-IR e IMC, insulina e IMC, peso e HOMA e entre insulina e peso; também foi constatado que, quanto maior for o IMC, maior será o valor de HOMA. CONCLUSÕES: Os resultados do presente estudo permitem concluir que há uma forte associação entre o hiperinsulinismo e a obesidade, devendo ser tomadas algumas medidas para evitar o ganho de peso durante a infância e a adolescência.

OBJECTIVES: To determine the relationship between body mass index (BMI), homeostasis model assessment - insulin resistance (HOMA-IR) and insulinemia. METHODS: This was a prospective cross-sectional observational study of 132 prepubescent schoolchildren residents in the municipality of Santo André, Brazil. Children underwent anthropometric assessment, their glycemia and insulinemia were measured and their HOMA-IR index calculated. RESULTS: Seventy-eight of the 132 children (59.1 percent) were girls and 54 were boys (40.9 percent), with a mean age of 8.7 years and mean BMI of 13.7 kg/m². A significant positive association was detected between HOMA-IR and BMI, insulin and BMI, weight and HOMA and between insulin and weight. It was also found that the higher the BMI, the greater the HOMA score. CONCLUSIONS: The results of this study allow for the conclusion that there is a strong association between hyperinsulinism and obesity. Measures should be taken to avoid weight gain during childhood and adolescence.

Evaluation of chemiluminescence method for the analysis of plasma homocysteine and comparison with HPLC method in children samples / Avaliação do método de quimioluminescência na análise de homocisteína plasmática e sua comparação com o método de HPLC em amostras de crianças

Objective: To compare the results for homocysteine concentration using chemiluminescence and HPLC methods in samples from school-age children. In addition, to determine the reference values for patients of this age group and assess the real prognostic value of homocysteine in healthy children. Methods: A prospective observational study was undertaken to determine plasma levels of homocysteine using two different assays, HPLC and chemiluminescence, in 185 samples from school-age children living in Santo Andre, with no chronic or inflammatory diseases, and absence of pubertal development. Results: The results were presented in percentiles and reference values were determined within this age group (7-9 years old). Homocysteine concentration ranged from 2.0 to 9.9 mumol/l (r = 0.821 and p < 0.001). Conclusions: It was verified that chemiluminescence is comparable to HPLC when both techniques are used to detect homocysteine in school-age children. There is an important correlation between both methods, which allows investigation of this amino acid as a risk factor for heart diseases.

Objetivo: Comparar os resultados da concentração de homocisteína usando os métodos de quimioluminescência e HPLC em amostras de crianças escolares. Determinar os valores de referência desse grupo etário e avaliar o valor prognóstico real da homocisteína em crianças saudáveis. Métodos: Um estudo prospectivo observacional foi executado para determinar os níveis de homocisteína usando dois ensaios diversos, o HPLC e a quimioluminescência, em 185 amostras de crianças em idade escolar moradoras da cidade de Santo André, que não apresentassem doenças crônicas ou inflamatórias, na ausência de desenvolvimento puberal. Resultados: Os resultados foram apresentados em percentis e os valores de referência foram determinados para esse grupo etário (7-9 anos). As concentrações de homocisteína variaram de 2,0 a 9,9 miumol/l (r = 0,821 e p < 0,001). Conclusões: Verificamos que o método da quimioluminescência é comparável ao método HPLC quando as técnicas são usadas para detectar a homocisteína em crianças em idade escolar. Houve importante correlação entre os dois métodos, o que permite a investigação desse aminoácido como um fator de risco para doenças cardíacas.