In this work, he has used the rat as a model. Innovative new approaches have been taken using stable isotopes and the appearance of labelled compounds in the brain, liver and gut and the specific labelling of different classes of lipids. We hope to be able to extend this approach into the effects of diseases, particularly those affecting fat absorption, and the essential fatty acid requirements of children with cystic fibrosis. In collaboration with Dr. Ron Ball , Dr. Paul Pencharz has systematically pursued the question of amino acid needs in the parenterally fed human neonate. Presently, most of that work has been done in their piglet model.
Parallel studies are ongoing in human neonates on parenteral nutrition.
The animal work is done with radioisotopes and the infant work with stable isotopes. In addition, we have been developing new techniques, notably the indictor amino acid oxidation technique, to be able to study amino acid requirements not only in healthy adult volunteers but also in children. The simplification of the indicator amino acid oxidation technique has permitted us to embark on studies of tyrosine need in children with phenylketonuria. All rights reserved.