Perfil de aminoácidos plasmáticos en adolescentes saludables embarazadas de Maracaibo, Venezuela / Plasma amino acids profile of healthy pregnant adolescents in Maracaibo, Venezuela

One hundred female adolescents (13-18 y) were clinical and anthropometrically studied to select only those with adequate nutrition. Most adolescents belonged to IV socio-economic stratum families (worker class). Height, weight, age, body mass index and medial arm circumference were used as anthropometric parameters. After screening, only 41 non pregnant girls (control) and 42 pregnant girls with adequate nutrition were selected to analyze plasma amino acids. Fasting peripheral venous blood was drawn, and plasma amino acids were analyzed by HPLC. Amino acid concentrations were expressed as umol/L +/- SE. SAS/STAT program was used for statistical analysis. Amino acid values of control adolescent group were found in ranges reported by other investigators, with slight variations, mostly in diminution, presumably due to nutritional, metabolic or genetic conditions of people living in tropical regions. In pregnant healthy adolescents, distributed according to gestational age: < 32 weeks (n = 30) and > 32 weeks (n = 12), a diminution of total molar plasma amino acids was found, by comparing with control values. Ten amino acids (Pro, Gly, Gln, Arg, Ser, Orn, Tau, Leu, Thr and Val) appeared significantively diminished throughout gestation, being Gly. Gln and Arg most affected since earlier weeks. During the 2nd period. Thr and Val increased their grade of affectation; whereas some amino acids values (Orn, Pro and Tau) tended to recuperate. Several of affected amino acids are gluconegoenic, thus, they could be utilized to supply the energy required by the pregnant adolescent against her double stress: the fetus development and her own development. The plasma amino acid values reported in both, healthy non pregnant and pregnant adolescents, could be taken as regional referential profile of plasma amino acids in this poblational group for further research on adolescent and fetal--maternal malnutrition.

[Prevalence of sub-clinical vitamin A deficiency and malnutrition in slum children in Maraicabo - Venezuela]. / Prevalencia de deficiencia subclínica de vitamina A y desnutrición en niños marginales de Maracaibo--Venezuela.

The present cross sectional study was carried out to estimate the prevalence of vitamin A deficiency among children by means of clinics and conjunctival impression cytology (CIC), and nutritional status by anthropometric indicators H//A, W//A, W//H. The study population included 157 children 2-6 y old, from urban and rural slums of Maracaibo, Venezuela, Conjunctival impression cytology was performed by ICEPO standard procedure. Z-score was applied to anthropometric data with reference values of NCHS-WHO. No evidence of clinical or ophthalmologic signs of vitamin A deficiency were detected. The prevalence of subclinical vitamin A deficiency, as detected by abnormal CIC, was 35.4%, being higher in rural children (48.3%). These prevalence values are higher than the criteria laid down by WHO/UNICEF to indicate a public health problem (> 20%). Mild or moderate protein-energy global malnutrition and stunting were detected in 36.1% and 44.6% of children, respectively. Abnormal CIC was indistinctly observed (approximately equal to 35%) as much in children with adequate nutrition as in malnourished ones. There was no significant difference in the distribution of the CIC results in relation to nutritional status. The findings indicate that CIC and Z-score of nutritional anthropometric data are useful to characterize the risk of vitamin A deficiency and of malnutrition in communities. Beside the implementation of an integral nutritional program which includes supplementation, food fortification and dietary diversification, improvement of socio-economic and sanitation conditions and also the educational level, with emphasis on nutritional and health education, are highly recommended.

Imbalance of Individual Plasma Amino acids Relative to Valine and Taurine as Potential Markers of Childhood Malnutrition.

In the present study a typical plasma amino acid profile for a defined population of healthy Venezuelan children was established and, further, the possibility was examined that deviations from such normalized amino acid patterns can be of use to warn of an impending nutritional deficiency, caused, in part, by adverse socio-economic conditions. This study comprised 152 children of both sexes ranging in age from 1 to 6 years. Classification into different socio-economic strata, ranging from impoverished to privileged, was evaluated by Graffar's method, as previously adapted by Mendez Castellano for Venezuela. The results of clinical and anthropometric examinations were used to group these children into 5 classes of nutritional sufficiency, ranging from adequate nutrition to severe undemutrition. The present data indicate that deviations in the plasma amino acid concentration profile, standardized for a defined population, can be used in combination with clinical evaluations to determine the type as well as the severity of inadequate nutrition. Abnormal ratios of several individual amino acids relative to Val and Tau may serve as early signs of (impending) undemutrition or malnutrition in children; the amino acid changes are detectable even in groups of children without any clinical signs but where sociological circumstances suggest a possibility of inadequate nutrition. Other uses for such plasma amino acid profiles may be to distinguish whether the detected amino acid abnormalities are of dietary or genetic origin, provided that the selected groups or individuals studied derive from a population with more or less the same genetic homogeneity and similar dietary customs.