Factores asociados a la concentración de retinol sérico en lactantes

OBJETIVO: Verificar los factores asociados a la concentración de retinol en lactantes atendidos en el servicio público de salud del área urbana de la ciudad de Viçosa (Minas Gerais, Brasil). MÉTODOS: Estudio de corte transversal realizado con 101 niños, de 18 a 24 meses, atendidos en el servicio de salud del área urbana de la ciudad de Viçosa. El análisis de la concentración de retinol en la sangre venosa fue realizado por cromatografía líquida de alta eficiencia. Para evaluación de la práctica alimentar, se utilizó el recordatorio de 24 horas. Las entrevistas fueron realizadas con los padres o responsables de los niños en sus domicilios. Para evaluar las variables asociadas al retinol sérico, se utilizó análisis de regresión lineal múltiple. RESULTADOS: Se identificó 39,6% de prevalencia de la deficiencia de vitamina A. Los factores asociados positivamente al nivel sérico de retinol fueron tiempo de escolaridad paterna e ingestión de proteína. Por otra parte, el número de moradores en el domicilio y la edad del niño estuvieron negativamente asociados. CONCLUSIONES: La hipovitaminosis A se presenta como un problema de Salud Pública entre los lactantes del municipio de Viçosa. Factores socioeconómicos, dietéticos y biológicos se asocian a la deficiencia de la vitamina A en la población infantil.OBJETIVO: Verificar os fatores associados à concentração de retinol em lactentes atendidos em serviço público de saúde. MÉTODOS: Estudo de corte transversal realizado com 101 crianças de 18 a 24 meses, atendidas no serviço público de saúde da área urbana da cidade de Viçosa. A análise da concentração de retinol no sangue venoso foi realizada por cromatografia líquida de alta eficiência. Para avaliação da prática alimentar, utilizou-se o recordatório de 24 horas. As entrevistas foram realizadas com os pais ou responsáveis pelas crianças em seus domicílios. Para avaliar as variáveis associadas ao retinol sérico, foi utilizada análise de regressão linear múltipla. RESULTADOS: Identificou-se 39,6% de prevalência da deficiência de vitamina A. Os fatores associados positivamente ao nível sérico de retinol foram tempo de escolaridade paterna e ingestão de proteína. Por outro lado, o número de moradores no domicílio e a idade da criança estiveram negativamente associados. CONCLUSÕES: A hipovitaminose A se apresenta como um problema de Saúde Pública entre os lactentes do município de Viçosa. Fatores socioeconômicos, dietéticos e biológicos se associam à deficiência da vitamina A na população infantil

Body composition and risk for metabolic alterations in female adolescents

OBJECTIVE: To study anthropometrical and body composition variables as predictors of risk for metabolic alterations and metabolic syndrome in female adolescents.METHODS: Biochemical, clinical and corporal composition data of 100 adolescents from 14 to 17 years old, who attended public schools in Viçosa, Southeastern Brazil, were collected.RESULTS: Regarding nutritional status, 83, 11 and 6% showed eutrophia, overweight/obesity and low weight, respectively, and 61% presented high body fat percent. Total cholesterol presented the highest percentage of inadequacy (57%), followed by high-density lipoprotein (HDL - 50%), low-density lipoprotein (LDL - 47%) and triacylglycerol (22%). Inadequacy was observed in 11, 9, 3 and 4% in relation to insulin resistance, fasting insulin, blood pressure and glycemia, respectively. The highest values of the fasting insulin and the Homeostasis Model Assessment-Insulin Resistance(HOMA-IR) were verified at the highest quartiles of body mass index (BMI), waist perimeter, waist-to-height ratio and body fat percent. Body mass index, waist perimeter, and waist-to-height ratio were the better predictors for high levels of HOMA-IR, blood glucose and fasting insulin. Waist-to-hip ratio was associated to arterial hypertension diagnosis. All body composition variables were effective in metabolic syndrome diagnosis.CONCLUSIONS: Waist perimeter, BMI and waist-to-height ratio showed to be good predictors for metabolic alterations in female adolescents and then should be used together for the nutritional assessment in this age range

Potential mechanisms for the emerging link between obesity and increased intestinal permeability

Recently, increased attention has been paid to the link between gut microbial composition and obesity. Gut microbiota is a source of endotoxins whose increase in plasma is related to obesity and insulin resistance through increased intestinal permeability in animal models; however, this relationship still needs to be confirmed in humans. That intestinal permeability is subject to change and that it might be the interface between gut microbiota and endotoxins in the core of metabolic dysfunctions reinforce the need to understand the mechanisms involved in these aspects to direct more efficient therapeutic approaches. Therefore, in this review, we focus on the emerging link between obesity and increased intestinal permeability, including the possible factors that contribute to increased intestinal permeability in obese subjects. We address the concept of intestinal permeability, how it is measured, and the intestinal segments that may be affected. We then describe 3 factors that may have an influence on intestinal permeability in obesity: microbial dysbiosis, dietary pattern (high-fructose and high-fat diet), and nutritional deficiencies. Gaps in the current knowledge of the role of Toll-like receptors ligands to induce insulin resistance, the routes for lipopolysaccharide circulation, and the impact of altered intestinal microbiota in obesity, as well as the limitations of current permeability tests and other potential useful markers, are discussed. More studies are needed to reveal how changes occur in the microbiota. The factors such as changes in the dietary pattern and the improvement of nutritional deficiencies appear to influence intestinal permeability, and impact metabolism must be examined. Also, additional studies are necessary to better understand how probiotic supplements, prebiotics, and micronutrients can improve stress-induced gastrointestinal barrier dysfunction and the influence these factors have on host defense. Hence, the topics presented in this review may be beneficial in directing future studies that assess gut barrier function in obesity

Methodological and ethical aspects of the sexual maturation assessment in adolescents

OBJECTIVE To analyze methodological and ethical aspects in the sexual maturation assessment of adolescents. DATA SOURCES Books and theses, articles and legislations on the Medline, SciELO, Science Direct databases, besides institutional documents of the World Health Organization and the Pediatric Societies of Brazil and São Paulo, considering the period from 1962 to 2012. The following keywords were used in Portuguese and English: "sexual maturation", "self-assessment", "ethics", "OBJECTIVE assessment of sexual maturation", "puberty", "adolescent", and "adolescentdevelopment". DATA SYNTHESIS The sexual maturation assessment is used in populatinal studies and in clinical daily care. The direct evaluation is performed by a specialized physician, whereas the self-assessment is carried out by the adolescent. This evaluation should be carefully performed in the appropriate place, taking into account the ethical aspects. The patient should not be constrained and the physician must respect the privacy and the confidentiality. Before this evaluation and independently of the used method, the adolescent should receive information and explanation about the procedure and the tools that will be applied. Furthermore, the patient has the right to want or not an adult close to him. CONCLUSIONS Validation studies showed that self-assessment is inferior to clinical assessment and should, therefore, be performed only when the direct examination by physicians is not possible

Body fat location and cardiovascular disease risk factors in overweight female adolescents and eutrophic female adolescents with a high percentage of body fat

Excessive body fat, mainly abdominal fat, is associated with higher cardiovascular risk. However, a fat localisation measurement that would be more indicative of risk in adolescents has not yet been established. This study was conducted in order to evaluate the correlation between body fat location measurements and cardiovascular disease risk factors in female adolescents. A total of 113 girls – 38 eutrophic according to their body mass index but with a high percentage of body fat, 40 eutrophic with adequate body fat, and 35 with excessive weight – were evaluated using 15 anthropometrical measurements and 10 cardiovascular risk factors. The central skinfold was the best measurement for predicting variables such as glycaemia and high-density lipoprotein; waist circumference for insulin and homeostasis model assessment; coronal diameter for total cholesterol and low-density lipoprotein; sagittal abdominal diameter for triglycerides and leptin; hip circumference for blood pressure; and the central/peripheral skinfold ratio for homocysteine. The correlation between the measurements and the number of risk factors showed that waist circumference and the waist/stature ratio produced the best results. The results suggest that the body fat distribution in adolescents is relevant in the development of cardiovascular risk factors. Simple measurements such as waist circumference and the waist/stature ratio were the best predictors of a risk of disease and they should therefore be associated with the body mass index in clinical practice in order to identify those adolescents at higher risk

Circunferência da cintura e relação cintura/estatura: úteis para identificar risco metabólico em adolescentes do sexo feminino?

OBJETIVO: Avaliar se a medida da circunferência da cintura e a relação cintura/estatura (RCE) são preditoras de fatores de risco cardiovasculares em adolescentes do sexo feminino. MÉTODOS: Avaliaram-se 113 adolescentes de 14 a 19 anos quanto à antropometria (peso, estatura e circunferência da cintura), parâmetros bioquímicos e clínicos (colesterol total, LDL-C, HDL-C, triglicerídeos, glicemia de jejum, insulina, homeostasis model assessment to assess insulin resistance - HOMA-IR, leptina, homocisteína e pressão arterial). Considerou-se como ponto de corte de obesidade abdominal valores de cintura e RCE>percentil 90. RESULTADOS: As adolescentes com obesidade abdominal apresentaram valores significantemente maiores de triglicerídeos (exceto para a RCE), insulina, HOMA-IR, leptina, pressão arterial sistólica e diastólica; o HDL-C foi mais baixo no grupo com cintura >percentil 90, porém sem significância estatística (p=0,052). CONCLUSÕES: O presente estudo demonstrou que a cintura e a RCE são medidas úteis para identificar adolescentes do sexo feminino com maior risco cardiovascular; contudo, a circunferência da cintura, isoladamente, apresentou melhor desempenho

Intestinal permeability parameters in obese patients are correlated with metabolic syndrome risk factors

Altered intestinal permeability has been shown to be associated with metabolic alterations in animal models of obesity, but not in humans. The aim of this study was to assess intestinal permeability in obese women and verify if there is any association with anthropometric measurements, body composition or biochemical variables. Twenty lean and twenty obese females participated in the study. Anthropometric measurements, body composition and blood pressure were assessed and biochemical analyses were performed. Administration of lactulose and mannitol followed by their quantification in urine was used to assess the intestinal permeability of volunteers. The obese group showed lower HDL (p < 0.05), higher fasting glucose, insulin, HOMA index and lactulose excretion than the lean group (p < 0.05), suggesting increased paracellular permeability. Lactulose excretion showed positive correlation (p < 0.05) with waist and abdominal circumference. Blood insulin and the HOMA index also increased with the increase in mannitol and lactulose excretion and in the L/M ratio (p < 0.05). L/M ratio presented a negative correlation with HDL concentration (p < 0.05). We demonstrated that intestinal permeability parameters in obese women are positively correlated with anthropometric measurements and metabolic variables. Therapeutic interventions focused on intestine health and the modulation of intestinal permeability should be explored in the context of obesity

Postprandial lipid response to high-saturated and high-monounsaturated fat meals in normal-weight or overweight women

We evaluated postprandial response of the lipid metabolism markers after the intake of a high-saturated fat (HSM) or high-monounsaturated fat meal (HMM). A randomized, controlled and acute intervention study included 63 women (age 26.9 ± 6.1 years): 35 normal weight (NW) and 28 overweight (OW) (total body fat [TBF] 24.7 ± 3.9% and 36.6 ± 3.9%, respectively). After 12 hours of fasting, each subject was given one of the two test meals standardized, including 2 muffins and water (HSM, 42.1% of saturated fat acid, or HMM, 34.5% of monounsaturated fat acid). Plasma fatty acid profile and concentrations of apolipoproteins A1 and B100, complement C3, and triacylglycerols were analyzed during fasting and at 2, 3, and 5 postprandial hours. Among the markers studied, the triacylglycerol (TAG) and complement C3 were significantly higher in the OW group, compared to NW. The increment in the C3 concentration was higher after HSM intake, compared with HMM (iAUC = 4365.5 ± 5477.4 vs. 1215.2 ± 882.4; p = 0.006), with no differences between groups. After 5 hours postprandial, plasma oleic acid values remained high compared with the fasting value in the NW group, but not in the OW group (26.0 ± 4.2 vs 23.7 ± 3.9%; p < 0.001). Women with high percentage of total plasma saturated fatty acids (SFA) at the beginning of the intervention had higher incremental area under the curve (iAUC) for the palmitic, stearic, and total fatty acids (p < 0.005). Those women with a high percentage of monounsaturated fatty acids (MUFA) showed lower iAUC values for the same fatty acid profile (p < 0.005). This study demonstrated the effect of the HSM on postprandial increment of C3 concentration, suggesting another mechanism for saturated fat metabolism. The postprandial response to HSM appears to be the mediated by baseline lipid profile of the individuals, while the response to HMM was correlated to the weight status