ABSTRACT
Abstract Objective To investigate associations of maternal and cord blood cytokine patterns with newborn size and body composition. Methods This cross-sectional study involved 70 pregnant women and their healthy newborns selected from the "Araraquara Cohort Study". Newborn anthropometric measurements were recorded at birth. Body composition was evaluated by air displacement plethysmography. Maternal blood samples were collected from pregnant women between 30 and 36 weeks of gestation, and umbilical cord blood samples were collected immediately after placenta discharge. The concentrations of the cytokines were determined in plasma by ELISA. Multiple linear regression models were used to assess associations between maternal and cord blood cytokine concentrations and newborn anthropometry and body composition measurements. Results Maternal plasma TGF-β1 concentration was inversely associated with newborn weight (β= -43.0; p= 0.012), length (β= -0.16, p= 0.028), head circumference (β= -0.13, p= 0.004), ponderal index (β= -0.32, p= 0.011) and fat-free mass (β= -0.05, p= 0.005). However, the association persisted just for head circumference (β= -0.26; p= 0.030) and ponderal index (β= - 0.28; p= 0.028), after adjusting for pre-gestational BMI, gestational weight gain, gestational age, hours after delivery, newborn sex, smoking and alcohol consumption. Conclusions Maternal plasma TGF-β1 concentration may be involved in the regulation of newborn size, mainly head circumference and ponderal index. Further cohort studies are necessary to investigate the role of TGF-β1 in different trimesters of pregnancy and its effect during the early stages of fetal development.
ABSTRACT
Objective: To measure the accuracy of predictive equations of resting metabolic rate (RMR) in obese teenagers in relation to indirect calorimetry (IC). Methods: This study was conducted with 116 obese teenagers (60 males; 13.7±1.1 years). The RMR was calculated from Harris and Benedict, Schofield, WHO, Henry and Rees equations. The RMR was measured by the QUARK-RMR system. The comparison between predictive equations and IC was by the Student's t test. The reliability of data between predictive equations and IC was verified by the typical error of measurement (TEM) and the coefficient of variation (CV%). Results: Henry's equation was significantly different from IC (p<0.02). The CV% found for each equations compared to IC turned was low. However, when the TEM was measured it was considered high in absolute values which can cause errors when estimating the RMR. Therefore, it is important that specific predictive equations are developed for Brazilian obese teenagers.
Objetivo: Medir la precisión de las ecuaciones predictivas de la tasa metabólica de reposo (TMR) en los adolescentes obesos en relación con la calorimetría indirecta (CI). Métodos: El estudio se realizó en 116 adolescentes obesos (60 niños, 13,7 ± 1,1 años). La TMR se calculó a partir de las ecuaciones predictivas de Harris y Benedict, Schofield, OMS, Henry y Rees. La TMR se midió por el sistema de QUARK-TMR. La comparación entre las ecuaciones de predicción y IC se realizó mediante el test t de Student. La fiabilidad de los datos entre IC y ecuaciones de predicción fue verificada por el error típico de la medición (TEM) y el coeficiente de variación (CV%). Resultados: La ecuación de Henry fue significativamente diferente de IC (p <0,02). El CV% encontrado para cada ecuación en comparación con IC fue bajo; no obstante, cuando se midió el TEM, este fue considerado alto en valores absolutos que puede provocar errores al estimar la TMR. Por lo tanto, es importante que ecuaciones de predicción específicas sean desarrolladas para adolescentes obesos brasileños.