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The object of this study was to determine in 12 healthy subjects the relation between gastric secretion of acid and absorption of calcium from two different preparations of calcium, as judged from increased outputs of calcium in the urine. The increase in urinary output of calcium after solid calcium carbonate was greater in the subjects with the most gastric secretion of acid. The absorption of calcium after a solution of monocalcium citrate was independent of gastric secretion of acid. In the four subjects with the least gastric secretion of acid, there was no absorption of calcium after calcium carbonate, but the absorption after monocalcium citrate was as great as that for those who secreted greater amounts of acid.

(1) During the light, all treatments reduced voluntary activity. (2) In the dark, estrogens increased, while estrogens in combination with restricted diet decreased, horizontal activity. (3) In the dark, restricted diet alone had little effect on voluntary activity, but reduced it when combined with estrogen treatment. (4) All treatments reduced responses to the olfactory stimulus. The dependence of results on time of day was unexpected. Further, different patterns of results for the three treatments suggest that estrogens and food restriction did not have equivalent or additive effects on arousal. While contrary to the main prediction, these findings are discussed in terms of the animals' adaptive preparations for reproduction [Schneider, J.E., 2006. Metabolic and hormonal control of the desire for food and sex: implications for obesity and eating disorders. Horm. Behav. 50, 562-571].

We hypothesized that more rapidly growing preterm infants would have higher rates of protein synthesis than term infants, and that protein synthesis would be more closely related to intracellular than plasma levels of amino acids. Neutrophils, used as a cell model, were isolated from 1-3 ml blood of 63 infants 27-44 wk postconceptual age. Protein synthesis (3H-leucine incorporation, pmol/h/mg DNA), and 19 amino acids in the leukocytes (nmol/mg DNA) and plasma (nmol/ml) were quantified. Protein synthesis was related inversely to birth weight and gestational age, i.e. the smaller and more preterm the infant the higher the rate of protein synthesis. Multiple regression analysis limited to six steps indicated that some plasma amino acids (Val, Ile, Phe, Asp, Ala, Tau) accounted for a significant (p = 0.03), but relatively small, proportion, 23%, of the variance in protein synthesis. A greater proportion of the variance in protein synthesis was explained by a set of six intracellular amino acids (Leu, Met, Tyr, Gly, Ala, Tau), with R2 = 36%, p = 0.001. Further, multiple regression identified specific combinations of six plasma amino acids which best explained ("predicted") the levels of each intracellular amino acid predictor of protein synthesis (R2 = 0.4-0.5, p less than 0.001-0.0001). Activities of some rate-limiting glycolytic enzymes, pyruvate kinase and phosphofructokinase, were correlated with protein synthesis in the leukocytes (p = 0.036, and 0.002, respectively). Phosphofructokinase, the major regulating enzyme in glycolysis, also was negatively correlated with birth weight and gestational age.(ABSTRACT TRUNCATED AT 250 WORDS)