Browsing by Author "Lewis, Barry"

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    Studies in cholestrol metabolism
    (1958) Lewis, Barry
    The biochemistry of the steroids is of unique interest; no other group of relatively simple substances plays so versatile a role in biology. On the one hand are many highly potent steroids occurring in minute quantities e.g. sex hormones, corticosteroids, the vitamins D and the cardiac glycosides. In sharp contrast are certain sterols, exemplified in the animal kingdom by cholesterol - familiar, abundant, easily determined, yet singularly obscure in their physiological significance. In some restricted fields the functions of cholesterol are known. It is a precursor of the adrenocortical hormones (perhaps not an obligatory one ), and is probably important in the biosynthesis of sex hormones too. Present in the skin is 7-dehydrocholesterol, converted to vitamins D by ultraviolet light. Cholesteryl esters are found in large quantities, together with sphingomyelin, in the myelin sheaths of nerve fibres, where these lipids may have an insulating function necessary at least for saltatory conduction.
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    The plasma corticosteroids: their determination and normal variations
    (1956) Lewis, Barry
    The current interest in the secretions of the adrenal cortex is shared by physiologist, physician and pharmacologists alike. such attention is not surprising in the case of a gland which is immediately essential to life, which can produce syndromes as varied as precocious puberty, virilisation; Addison's disease; Cushing's syndrome, and the newly described hyperaldosteronism syndrome of Conn (1955), a gland which has been implicated in the parthenogenesis of diabetes (Hoet and Lukens, 195; Jackson, 1955), hypertension (Sepeika, 1948, 1955), pre-eclampsia, and atherosclerosis, and which profoundly effects so many of the metabolic processes of the body. The need for accurate measurement of adrenocortical function has therefore been accentuated in recent years. The purpose of this study was to find out as direct a method as possible for determining the rate of secretion of this gland and to define with this method the norms and normal variations.