Audrey Boyer

The protein requirement of the premature infant. I. The effect of protein intake on the retention of nitrogen

The effect of high-and low-protein intakes on nitrogen retention in premature infants was studied. Infants fed the higher amount of protein retained much greater amounts of nitrogen. Since weight gain in the two groups was similar, it is concluded that infants fed high-protein diets have accelerated chemical maturation and attain a more mature body composition at an early age.

The Essential Amino Acid Requirements of Infants IX. Isoleucine

Acurate knowledge of essential nutrients is a sine qua non of good nutrition. Such information is needed for the prevention and repair of dietary deficiencies arising from food shortages and also in situations where the capacity to handle food is limited by disease states. Evaluation of the requirements for essential amino acids has been peculiarly difficult, since this involves the construction of a diet in which the quantity of a single amino acid can be varied at will. The problem has been approached in several ways: 1. Use has been made of natural proteins deficient in one or another amino acid. This method has very limited applicability, for nature has been singularly unobliging in providing a variety of such proteins. 2. Chemically degraded proteins or protein hydrolysates have been used. A number of procedures can be used to destroy one or more amino acids, which can then be replaced in any quantity desired. Diets constructed from such preparations have the advantage that the amino acids are present for the most part as the natural isomers and that unessential as well as essential amino acids are present. There is, however, the disadvantage that the na

The chloride concentration of saliva and sweat in infancy

Summary 1. The chloride concentration of the saliva at birth is high in both premature and term infants and falls rapidly during the first week of life. 2. The salivary chloride concentration continues to fall at a much slower rate during the first two years of life and then appears to stabilize through 10 years of age. 3. On the other hand, the chloride concentration of sweat is low at birth, even in the premature infant. 4. The importance of these observations in the diagnosis of cystic fibrosis of the pancreas is pointed out. 5. The possible relation of salivary chloride concentration to the presence of the staphylococcus in the nose and throat is discussed.