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L B Bailey

Publications and source records attributed to L B Bailey.

63 records · Page 4Linked to original sources
PubMed1978

Effect on nitrogen retention by adults of different proportions of indispensable amino acids in isonitrogenous cereal-based based diets.

Nitrogen retention of adults who consumed diets in which cereals furnished 6.0 g N and 0.9 g of lysine was improved by increasing lysine to 1.8 g without altering other amino acids. In a second experiment, 70% of the 6.0 g of dietary N was supplied by rice + wheat and 30% by mixtures of amino acids so designed that the total intakes of amino acids were equivalent to those in diets containing 6.0 g N from whole egg (E), egg + potato (EP), rice + wheat (RW), rice + soy (RS), wheat + milk (WM) or corn + beans (CB). Mean N balances of young men in descending order were, g/day: E 0.69 +/- 0.23, RS 0.44 +/- 0.15, EP 0.43 +/- 0.09, WM 0.24 +/- 0.16, CB 0.16 +/- 0.13 and RW -0.02 +/- 0.10. In the same order, these diet provided, g/day: lysine 2.6, 1.9, 2.3, 1.6, 1.4 and 1.0; S-acids 2.2, 1.7, 1.6, 2.2, 1.9 and 2.3; and tryptophan 0.7, 0.4, 0.6, 0.5, 0.3 and 0.4. N balances resulting from diets E, RS and EP did not differ significantly from each other but E was superior to CB and RW (P less than 0.01). Relative amounts and propertions of the essential amino acids could be varied without altering nitrogen retention until at least one amino acid became limiting. Several patterns of indispensable amino acids therefore may be equally effective in meeting needs of adults, but both amounts and relative proportions should be considered.

Adult↗
PubMed1977

Lysine and tryptophan in cereal-based diets for adult human subjects.

A basic diet containing rice, wheat, and corn that furnished 6.0 g of nitrogen per day was consumed by health young adults. Two levels of lysine, 900 and 1800 mg, and three of tryptophan, 260, 390, and 520 mg, were tested. Lysine exerted a significant effect (P less than 0.05) on nitrogen retention but tryptophan did not. When consumed in conjunction with at least twice the reported minimal requirements of other essential amino acids, 900 mg of lysine induced mean daily balances of 0.15 +/- 0.18, 0.19 +/- 0.14, and 0.22 +/- 0.21 g, respectively, in response to the three levels of tryptophan; and 1800 mg of lysine caused retentions of 0.75 +/- 0.14, 0.77 +/- 0.21 and 0.71 +/- 0.15 g. These findings are discussed in relation to fulfillment of protein and amino acid requirements of adult human subjects.

Adult↗
PubMed1977

Nitrogen retention of young men who consumed isonitrogenous diets containing normal, opaque-2 or sugary-2 opaque-2 corn.

Three isogenic lines of corn provided two levels of nitrogen for young men, but the diets were isonitrogenous at 5.5 g. Mean daily nitrogen balances were -0.28 +/- 0.34, +0.31 +/- 0.23 and 0.40 +/- 0.08 g, respectively, when normal, opaque-2 and sugary-2 opaque-2 corn furnished 5.5 g of nitrogen; and -0.07 +/- 0.17, +0.38 +/- 0.21 and -0.04 +/- 0.25 g when corn supplied only 4.4 g of nitrogen. Although these values were not significantly different, both high-lysine varieties tended to be superior to normal corn at 5.5 g of nitrogen and opaque-2 corn caused improvement even at 4.4 g of nitrogen. Lysine and tryptophan were higher and leucine lower in both opaque-2 and sugary-2 opaque-2 than in normal corn. Coefficients of apparent digestibility were between 65.5% and 68.8%.

Adult↗
PubMed1976

Nitrogen retention and plasma amino acids of adults who consumed isonitrogenous diets containing rice and milk or wheat versus their constituent amino acids.

Nitrogen retention and concentrations of plasma amino acids were compared when young adults consumed isonitrogenous diets containing proteins (3.0 g of N from rice plus 3.0 g of N from milk or 3.0 g of N from rice plus 3.0 g of N from wheat flour) or mixtures of their constituent amino acids. Diets containing proteins induced greater nitrogen retention than did those containing corresponding amounts of amino acids in crystalline form, and the difference between the combinations of proteins was delineated more sharply. Concentrations of several amino acids were elevated by substituting crystalline amino acids for proteins, especially in postprandial plasma. Subjects responded differently to addition of the limiting amino acids, lysine and tryptophan, to the diets containing amino acids instead of rice plus wheat. Therefore, data obtained by means of combinations of cereals and by mixtures of their constituent amino acids cannot always be used interchangeably.

Adult↗
PubMed1976

Plasma amino acids and nitrogen retention of human subjects who consumed isonitrogenous diets containing rice and wheat or their constituent amino acids with and without additional lysine.

Six diets furnished 6.0 g of nitrogen to adult human subjects as follows: a combination of rice and wheat; mixtures in which either 100 or 50% of the amino acids in rice and wheat were replaced by their constituent amino acids; and similar diets in which lysine was increased from 1.2 to 1.8 g. Nitrogen retention was greater (P less than 0.01) and concentrations of several amino acids in plasma were lower when the cereals were supplemented with lysine than when all other diets were fed. Data obtained with mixtures of amino acids apparently cannot always be used interchangeably with that from cereal-based diets, even when amino acid content is the same. Changes in plasma amino acids are a useful indicator of utilization of dietary amono acids when nitrogen balance also is determined.

Adult↗
PubMed1975

Nitrogen retention and plasma amino acids of men who consumed isonitrogenous diets containing egg albumen or mixtures of amino acids.

Experimental diets that furnished approximately 6.0 g of nitrogen per day were consumed by young men. Nitrogen retention was not altered significantly when egg albumen was replaced by its constituent essential and nonessential amino acids or by the essential amino acids (including cystine, tyrosine and histidine) plus a source of nonspecific nitrogen. Concentrations of essential amino acids in fasting or postprandial plasma were not influenced significantly by source of amino acids or by replacement of nonessential amino acids by nonspecific nitrogen; but concentrations of certain nonessential amino acids were altered by treatment. Responses to an elemental diet or to a similar diet in which egg albumen replaced the amino acid mixture did not differ significantly.

Adult↗
PubMedDate not supplied

Total parenteral nutrition in the mouse: development of a technique.

A method for total parenteral nutrition in the mouse was developed using commercially available supplies and equipment. The mouse's inferior vena cava was catheterized and the catheter was exteriorized from the tail. Mice (average body weight 22.5 g) were not tethered but instead were partially restrained by immobilizing the tail to protect the infusion tubing. A solution was formulated to contain 40% dextrose and 4.3% amino acids plus vitamins, electrolytes, and trace elements. It was administered via pump in graded fashion for the first 3 days to allow the mice to adapt, and then at a rate of 8 ml/day thereafter. This volume provided approximately 12 kcal and 54 mg nitrogen per day and was calculated to meet the needs of the mouse fed per os according to guidelines of the National Research Council. During the adaptation period mice lost weight but they were in positive N balance thereafter. At the end of 12 days body weight was not different than at the start, indicating the adequacy of nutrient input. Further, there were no differences in nitrogen balance or body weight in total parenteral nutrition fed mice in comparison with tail-restrained mice given the same solution per os. All mice appeared to tolerate the partial restraint without incidence and showed no untoward side effects. The rationale and validity of this technique is discussed in detail.

Animals↗
PubMedDate not supplied

Total parenteral nutrition in the mouse: body composition and plasma chemistries.

Mice that were maintained in energy and nitrogen (N) balance by total parenteral nutrition (TPN) for 12 days were analyzed for changes in organ weight, carcass and liver N and fat, and plasma glucose, urea N, and total protein. The results are compared with two other groups: (1) PO, which consisted of mice that were given the TPN solution per os in amounts equivalent to the TPN group, and (2) AL, which consisted of mice allowed to consume a stock diet ad libitum. In comparison with group AL, the TPN-fed mice had normal liver, kidney, and lung weights but heavier spleens and hearts. Group PO had an increase in liver weight only. Hepatic lipid content declined in group TPN but increased markedly in PO-fed mice. The latter group also demonstrated a 35% increase in carcass fat whereas it was unchanged in the TPN group. No differences were found in plasma urea N and total protein among the groups but plasma glucose increased 2-fold in group PO. It appears that our technique of parenteral feeding in mice maintains fairly normal body composition and plasma chemistries. However, mice drinking the TPN solution (group PO) exhibited the greatest number of alterations. These results are discussed in relation to differences in route of feeding, diet composition, feeding pattern, and the possible influence of circadian rhythms. The dilemma of choosing appropriate control groups in TPN studies is also discussed.

Animals↗