Browsing by Subject "metabolism"

Now showing 1 - 4 of 4
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    An investigation of certain aspects of pyruvate metabolism in man by indirect and direct tolerance tests
    (1967) Lange, Leo Stanley
    The purpose of this project has been to test the postulate that high blood levels of pyruvate encountered in certain conditions such as steroid excess, diabetes mellitus under certain circumstances, and thiamine deficiency, are due to defective removal of pyruvate rather than excessive production. Specific methods of assay and direct studies of pyruvate tolerance were used. Intermediary carbohydrate metabolism was studied in a total of 109 subjects. The history of thiamine deficiency and of the concept of ensymes is outlined and the literature on pyruvate estimation and study in various clinical conditions is reviewed. Direct tests of pyruvate tolerance are discussed and the biochemistry if glucose breakdown is described. the history of analytical methodology for pyruvate is recounted.
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    ATPase and Multidrug Transport Activities of the Overexpressed Yeast ABC Protein Yor1p
    (1998) Decottignies, Anabelle; Grant, Althea M; Nichols, J Wylie; de Wet, Heidi; McIntosh, David B; Goffeau, André
    The Saccharomyces cerevisiae genome encodes 15 full-size ATP binding cassette transporters (ABC), of which PDR5, SNQ2, and YOR1 are known to be regulated by the transcription factors Pdr1p and Pdr3p (pleiotropic drug resistance). We have identified two new ABC transporter-encoding genes, PDR10 and PDR15, which were up-regulated by the PDR1-3 mutation. These genes, as well as four other ABC transporter-encoding genes, were deleted in order to study the properties of Yor1p. The PDR1-3 gain-of-function mutant was then used to overproduce Yor1p up to 10% of the total plasma membrane proteins. Overexpressed Yor1p was photolabeled by [gamma-32P]2', 3'-O-(2,4,6-trinitrophenyl)-8-azido-ATP (K0.5 = 45 microM) and inhibited by ATP (KD = 0.3 mM) in plasma membranes. Solubilization and partial purification on sucrose gradient allowed to detect significant Yor1p ATP hydrolysis activity (approximately 100 nmol of Pi.min-1.mg-1). This activity was phospholipid-dependent and sensitive to low concentrations of vanadate (I50 = 0.3 microM) and oligomycin (I50 = 8.5 microg/ml). In vivo, we observed a correlation between the amount of Yor1p in the plasma membrane and the level of resistance to oligomycin. We also demonstrated that Yor1p drives an energy-dependent, proton uncoupler-insensitive, cellular extrusion of rhodamine B. Furthermore, cells lacking both Yor1p and Pdr5p (but not Snq2p) showed increased accumulation of the fluorescent derivative of 1-myristoyl-2-[6-(NBD)aminocaproyl]phosphatidylethanolamine. Despite their different topologies, both Yor1p and Pdr5p mediated the ATP-dependent translocation of similar drugs and phospholipids across the yeast cell membrane. Both ABC transporters exhibit ATP hydrolysis in vitro, but Pdr5p ATPase activity is about 15 times higher than that of Yor1p, which may indicate mechanistic or regulatory differences between the two enzymes.
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    Forensic Medicine - Alcohol Metabolism
    (2021-11-16) De Waal, Celeste
    This lightboard video is the second of three in a series, and linked to the re-enactment of the examination of an intoxicated driver video. This video graphically depicts the metabolism of alcohol as related to the (blood) alcohol curve. This foundational knowledge underscores the principles behind the examination of the intoxicated individual. It touches on aspects related to the timing of the collection of a suitable sample, mostly blood, to analyse the alcohol concentration of an arrested individual. This video can be applicable across health professions from medical students to doctors and nursing staff.
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    Studies bearing on: (1) The nutrition of Bantu infants and young children and (2) The metabolism of calcium and iron by Bantu children and adults
    (1964) Walker, Alexander Robert Pettigrew
    The continent of Africa is inhabited by about 270 million persons of whom about 60 million are Bantu. They dwell mainly south of the Equator. South African Bantu number about 11 million persons, of whom under a third are urbanised, and over a third each work on farms of Whites or live in the Native Reserves. These local Bantu are comprised of several ethnic groups, the largest of which are Zulu and Xhosa. While some communities of rural Bantu still live in a primitive manner. others, mainly in urban areas, tend progressively to adopt a westernised type of diet and manner of life. The Bantu may therefore be observed in all stages of transition, in relation to patterns of diet, metabolism, and pathology. The studies undertaken and to be described concern primarily the nutrition of infants and children, the prevalence of certain deficiency diseases, and the handicap imposed by parasitism on nutritional state and other parameters.