RESUMO
Size at birth is related to the risk of heart disease, hypertension and diabetes mellitus in later life. Glycine is a conditionally essential amino acid during the perinatal period. The urinary execretion of 5-1-oxoproline has been used as a marker for glycine sufficiency. In Jamaican infants, excretion increased progressively during the first weeks of life and by 6 weeks of age was two-to-three times that seen in infants in the UK. We measured the rate of excretion in 42 infants aged 4-to-6 weeks, delivered at Mount Hope Maternity Hospital (Indian, 17; African, 15; mixed, 10), compared with 22 Caucasian infants born in Southampton. There were no differences between the groups in maternal age, maternal haemoglobin, or parity. Trinidadian infants were statistically significantly lighter, with smaller head circumference than the infants in UK. The differences in weight were more marked for the Indian and mixed infants than for the African infants, although head circumference in the three groups was similar. There was a highly statistically significant increase in the excretion of 5-oxoproline in all groups of Trinidadian infants, compared with UK infants. Maternal haemoglobin related to newborn size. When maternal haemoglobin was controlled, there was a statistically significant inverse relationship between 5-oxoproline excretion and birthweight (r=-0.32, p=0.02) and head circumference (r=-0.27, p=0.05). Infants in Trinidad had levels of urinary 5-oxoproline similar to those found previously in Jamaica and about twice those seen in infants in the UK. These differences do not appear to be accounted for by infant feeding patterns, but may be directly related to aspects of maternal nutrition, and the shape and size of the infant at birth. The data suggest that the availability of glycine might be limiting for foetal growth in the Caribbean, and this could have important implications for the development of diabetes mellitus, hypertension and heart disease in later life (AU)
Assuntos
Estudo Comparativo , Humanos , Recém-Nascido , Desenvolvimento Embrionário e Fetal/fisiologia , Glicina , Prolina/urina , Peso ao NascerRESUMO
A case report of type II hyperprolinemia in a 5-year-old boy and its biochemical investigation is presented. The child has mild developmental delay, recurrent seizures of the grand mal type and EEG alterations. Although this disorder has been recently considered a benign condition, variants accompanied by characteristic symptomatology cannot be fully ruled out. The urinary excretion of high concentrations of N-(pyrrole-2-carboxylic acid)-glycine conjugate is stressed, since it appears that only one previous report in the literature described this compound in the urine of two patients affected by this disturbance.
Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/urina , Glicina/análogos & derivados , Prolina/metabolismo , Pirróis/urina , Erros Inatos do Metabolismo dos Aminoácidos/complicações , Erros Inatos do Metabolismo dos Aminoácidos/genética , Consanguinidade , Eletroencefalografia , Glicina/urina , Transtornos do Crescimento/etiologia , Humanos , Lactente , Masculino , Prolina/análogos & derivados , Prolina/urina , Recidiva , Convulsões/diagnóstico , Convulsões/etiologiaRESUMO
Vitamin-D deficiency is associated with secondary hyperparathyroidism, hypophosphatemia, generalized aminoaciduria, phosphaturia and, late in its course, hypocalcemia. The tubulopathy has been attributed to the elevated levels of circulating parathyroid hormone. To further delineate the mechanisms responsible for aminoaciduria, vitamin-D deficiency and/or phosphate depletion were induced by placing weanling Sprague-Dawley rats on one of the following diets for 5 weeks: (1) control = 0.7% P, 5.5 micrograms % vitamin D; (2) D-P- = 0.1% P, 0 microgram % vitamin D; (3) D+P- = 0.1% P, 5.5 micrograms % vitamin D; (4) D-P+ = 0.3% P, 0 microgram % vitamin D, and (5) D-P++ = 0.7% P, 0 microgram % vitamin D. Short-term P depletion was produced in a group of animals fed D-P++ for 4 weeks, then fed D-P- for another week. To study the effects of acute supplementation with a pharmacological dose of calcitriol on the transport of amino acids by renal brush border membrane vesicles, the latter experimental group received 500 pmol of calcitriol (and is known as the SUPP group), or an equal amount of the vehicle (and is referred to as the ETH group). The uptake of taurine and proline by renal brush border membrane vesicles was blunted by 50 +/- 3 and 40 +/- 5%, respectively, at the peak of the overshoot, in all diets except D-P++. No changes were observed in vesicle size or Vmax.(ABSTRACT TRUNCATED AT 250 WORDS)