In 1895, Hopkins described the white and yellow wing pigments of Pieridae as ' . . .excretory substances which function in ornament...' (Hopkins, 1895). ^ those days, it was generally recognized that purines, especially uric acid, were excretory products. Hopkins thought that the white substance was uric acid and that the yellow one was a derivative. In 1925 Wigglesworth still believed the wing...

In previous investigations it was shown that in folic acid deficiency there is a large increase in the urinary excretion of formimino-n-glutamic acid (l-6). This increase has been explained by recent enzymatic studies demonstrating that the first step in the metabolism of formimino+glutamic acid is the transfer of the formimino group to tetrahydrofolic acid (7-9). Formimino-n-glutamic acid is a...

A mildly affected Maroteaux-Lamy patient is described. Electrophoretic separation of acid mucopolysaccharides (MPS) in the urine showed an increased excretion of dermatan sulphate in spite of a normal total excretion of MPS.

It is well known that the tissues of albino rats, without an external source of vitamin C, contain appreciable concentrations of ascorbic acid as measured by staining techniques, chemical titration, and biological assay. The relative distribution and absolute concentrations appear to be fairly constant and regulated by synthesis in vivo, under most conditions of dietary regimen, but extreme var...

Urinary excretion of acid mucopolysaccharides of varying composition and amount has been found in a number of rare diseases, mainly affecting the connective tissues. Recently excretion of chondroitin sulphate and hyaluronic acid in the urine of a patient with mastocytosis has been described by Asboe-Hansen and Clausen (1963). Evidence of the presence of acid mucopolysaccharides in different org...

It is well known that the tissues of albino rats, without an external source of vitamin C, contain appreciable concentrations of ascorbic acid as measured by staining techniques, chemical titration, and biological assay. The relative distribution and absolute concentrations appear to be fairly constant and regulated by synthesis in vivo, under most conditions of dietary regimen, but extreme var...

Fibre supplements from wheat bran and sugar cane residue (bagasse) were added to the normal diet of volunteers for 12-week periods in a controlled metabolic study. Stool weights and stool fat excretion increased on both dietary fibres. Bagasse increased the daily loss of acid steroids, but bran failed to affect bile acid excretion. Decreased transit time without alteration in faecal flora occur...

I . Urinary excretion of total ether-soluble acids and of methylmalonic acid was studied in rats on vitamin BI2-deficient diets with and without a vitamin Blz supplement. 2. It was shown that urinary excretion of total ether-soluble acids and methylmalonic acid was increased in vitamin R1,-deficient rats and that this increase was somewhat variable between individual animals, males and females,...

Ascorbic acid is frequently administered intravenously by alternative health practitioners and, occasionally, by mainstream physicians. Intravenous administration can greatly increase the amount of ascorbic acid that reaches the circulation, potentially increasing the risk of oxalate crystallization in the urinary space. To investigate this possibility, we developed gas chromatography mass spec...

The sources and rates of metabolic acid production in relation to renal net acid excretion and thus acid balance in humans have remained controversial. The techniques and possible errors in these measurements are reviewed, as is the relationship of charge balance to acid balance. The results demonstrate that when acid production is experimentally increased among healthy subjects, renal net acid...