The deuterated-retinol-dilution technique provides a quantitative estimate of total-body vitamin A (TBVA) stores in adults. To apply the technique to children, information on plasma retinol kinetics ...in this age group is needed.
We described the plasma retinol kinetics of an oral dose of (2)H(4)retinyl acetate in a population of Peruvian children (12-24 mo of age) in order to examine the relation between TBVA stores and individual plasma isotopic ratios 3 d after the dose and to estimate 1) the time required for the isotope dose to mix with endogenous vitamin A, 2) the fractional catabolic rate for retinol, and 3) TBVA stores.
An oral dose of (2)H(4)retinyl acetate (14 micromol retinol equivalents) was administered to children (n = 107) to construct a population-level kinetic curve of the plasma ratio of (2)H(4)retinol to retinol to estimate equilibration time and the fractional catabolic rate. TBVA stores were estimated by using a modification of the isotope dilution equation for adults.
The dose of (2)H(4)retinyl acetate fully mixed with endogenous vitamin A 8 d after the dose. The fractional catabolic rate was 0.022/d (95% CI: 0.014, 0.030/d). Mean (+/- SD) TBVA stores were estimated as 0.097 +/- 0.081 mmol (range: 0.016-0.392 mmol). Plasma ratios of (2)H(4)retinol to retinol 3 d after the dose were correlated with the inverse of estimated TBVA stores (r = -0.74, P < 0.0001).
Compared with previous results in adults, the equilibration time occurred earlier and the estimated system fractional catabolic rate was higher in this population of children. The modified isotope dilution equation provided estimates of hepatic vitamin A concentration that are similar to values reported in US children at autopsy.
Specially collected, spray-dried bovine and porcine blood plasma have been incorporated previously in feeds of weanling farm animals, resulting in increased dietary intakes and greater rates of ...weight gain than observed in control animals. Before conducting similar trials in human populations, preliminary studies have been completed to assess the acceptability, safety, and digestibility of processed animal plasma in young children.
Masked study diets were provided sequentially to each of ten young, Peruvian children recovering from severe protein-energy malnutrition during three randomly ordered 7-day dietary periods. The control diet was prepared from rice, milk, vegetable oil, and sugar; the two study diets included spray-dried, bovine serum concentrate to replace either 25% or 50% of the milk protein of the control diet. Urine and feces were collected quantitatively during the last four days of each diet period to assess stool weight, apparent absorption of macronutrients, and retention of nitrogen.
All children consumed the entire amounts offered of each of the diets. The mean number of daily bowel movements and mean apparent absorption and retention of nitrogen and mean apparent absorption of carbohydrate were similar for each diet. Fractional absorption of dietary lipid and of total energy increased significantly in relation to the amount of bovine serum concentrate in the diet, although this might be explained by the simultaneous replacement of milk fat with additional vegetable oil.
Each of the diets was well accepted by the study children, and there was no evidence of any adverse effects of bovine serum concentrate.
Individual components of milk from humans and other mammalian species may influence the severity, duration, and nutritional outcome of childhood diarrhea in different ways. Nonetheless, empirical ...data from clinical trials can be used to assess children's responses to specific milk‐containing diets. Factors modifying the response to milk include its source, amount, frequency of feeding, type of processing, and accompanying foods, as well as the type and severity of enteric infection and specific characteristics of the host. Whereas breast‐fed infants have less severe diarrhea when breast milk is continued rather than interrupted, infants and children fed with non‐human milks tend to have more severe illness than those receiving milk‐free or lactose‐limited formulas or milk‐cereal mixtures. Fermentation of milk may reduce the severity of lactose malabsorption, but additional information regarding the efficacy of yogurt in acute, childhood diarrhea is still needed.
The deuterated-retinol-dilution technique provides a quantitative estimate of total-body vitamin A (TBVA) stores in adults. To apply the technique to children, information on plasma retinol kinetics ...in this age group is needed.
We described the plasma retinol kinetics of an oral dose of 2H4retinyl acetate in a population of Peruvian children (12–24 mo of age) in order to examine the relation between TBVA stores and individual plasma isotopic ratios 3 d after the dose and to estimate 1) the time required for the isotope dose to mix with endogenous vitamin A, 2) the fractional catabolic rate for retinol, and 3) TBVA stores.
An oral dose of 2H4retinyl acetate (14 μmol retinol equivalents) was administered to children (n = 107) to construct a population-level kinetic curve of the plasma ratio of 2H4retinol to retinol to estimate equilibration time and the fractional catabolic rate. TBVA stores were estimated by using a modification of the isotope dilution equation for adults.
The dose of 2H4retinyl acetate fully mixed with endogenous vitamin A 8 d after the dose. The fractional catabolic rate was 0.022/d (95% CI: 0.014, 0.030/d). Mean (± SD) TBVA stores were estimated as 0.097 ± 0.081 mmol (range: 0.016–0.392 mmol). Plasma ratios of 2H4retinol to retinol 3 d after the dose were correlated with the inverse of estimated TBVA stores (r = −0.74, P < 0.0001).
Compared with previous results in adults, the equilibration time occurred earlier and the estimated system fractional catabolic rate was higher in this population of children. The modified isotope dilution equation provided estimates of hepatic vitamin A concentration that are similar to values reported in US children at autopsy.
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