The effect of source of dietary carbohydrate on the plasma lipid concentrations and glucose tolerance were studied. Three women received diets which contained 16%, 40%, and 44% of calories as protein, fat, and carbohydrate, respectively. During the control period of six days the carbohydrate was derived from mixed sources. In subsequent six-day periods, 80% of the carbohydrate was supplied alternately by sucrose (Sugar Diet) or by polysaccharides from natural sources (Complex Diet). Total lipids, phospholipids, triglycerides, total and free cholesterol of the plasma were determined on the final day of each dietary period. The plasma concentrations of total lipids, phospholipids, and triglycerides were lowest following the Complex Diet. On the average, the Sugar Diet produced the same concentrations of these lipid fractions as did the Control Diet. No consistent changes in cholesterol could be attributed to dietary carbohydrate. Glucose tolerance tests were performed at the end of each dietary period. In the two young subjects, glucose tolerance did not seem to be associated with the dietary treatment. The older subject showed impaired glucose tolerance after the diet containing complex carbohydrate. / Graduation date: 1969

Typescript, etc.

No description available.

Food lipid systems are very complex and so is oxidative degradation that render them unpalatable for human consumption. The significance of lipid degradation and the key reactions involved have been thoroughly studied and are well understood today. This is not true, however, of the secondary products of the autoxidation reactions. Of the many hydroperoxide decomposition products, the carbonyls are generally considered the most important. Much work has been published on the identification of carbonyls in autoxidizing lipids and model systems, and in practically every case where oxidation mechanisms were considered, the authors have repeatedly referred to fatty acid hydroperoxides as immediate precursors. At the present time, there are a number of carbonyl compounds that are always observed in oxidized lipid systems that can not be explained by generally accepted mechanisms. In view of this, it seemed feasible to look for other possible substrates in lipids that are readily oxidized and that might account for some of the variety of carbonyls observed. The carbonyl compounds, themselves a product of autoxidation, were selected for this study. In a preliminary study, the carbonyl products of carefully autoxidized methyl linolenate was qualitatively and quantitatively compared to the theoretically derived carbonyls to determine those compounds not accountable by currently accepted mechanisms. The analysis included TBA number, peroxide value, total saturated and unsaturated carbonyl content and total saturated and unsaturated volatile carbonyl content. The volatile monocarbonyls were isolated by reduced pressure steam distillation, separated as 2, 4-dinitrophenylhydrazones by column chromatography and analyzed. Forty-seven percent of the oxygen consumed by linolenate was found in the hydroperoxides and 54 percent was found in the total carbonyl content. The monocarbonyls identified were ethanal, propanal, butanal, but-2-enal, pent-2-enal, hex-2-enal, hept-2-enal, oct-2-enal, hexa-2, 4-dienal, hepta-2, 4-dienal, and nona-2, 4-dienal. One member from each of the major monocarbonyl classes encountered in autoxidizing lipids was autoxidized under controlled conditions. The carbonyls selected were n-nonanal, non-2-enal, hepta-2, 4-dienal, and oct-l-en-3-one. Samples which had consumed 0.25 and 0.5 moles of oxygen per mole of sample were analyzed for peroxide, malonaldehyde, and acid production. The degradation products were analyzed, as 2, 4-dinitrophenylhydrazones, using column, paper, and thin layer chromatography, ultraviolet and infrared spectroscopy, and melting point determinations. Non-2-enal and hepta-2, 4-dienal oxidized immediately with no induction period, whereas, n-nonanal had an induction period of approximately 12 hours and oct-1-en-3-one did not oxidize when held at 45°C for 52 hours. The major oxidation product of non-2-enal was non-2-enoic acid. However, eight carbonyl compounds were identified as degradation products. These listed in order of decreasing concentrations were ethanal, n-heptanal, α-ketooctanal, n-octanal, propanal, glyoxal, α-ketononanal, α-ketoheptanal, and malonaldehyde (measured by the TBA reaction). The major oxidation products of hepta-2, 4-dienal were polymers. The carbonyl compounds produced by autoxidation, listed in order of decreasing concentrations, were propanal, ethanal, cisbut- 2-en-l, 4-dial, n-butanal, α-ketopentanal, glyoxal, malonaldehyde (measured by TBA reaction), α-ketohexanal, α-ketoheptanal. Hepta-2, 4-dienal produced 10 times more malonaldehyde and had a more pronounced pro-oxidant effect on methyl linoleate than non-2- enal. n-Nonanal had no pro-oxidant effect at the concentration used (0.1 percent). The above results coupled with data in the literature again clearly illustrated the complexity of oxidative degradation of food lipids. It was shown that many of the carbonyls in oxidized lipids could originate from the oxidation of the initially formed carbonyl compounds. This could account for many of the carbonyls which have been identified in oxidized lipids, but not explained by generally accepted oxidation mechanisms. / Graduation date: 1964

Thesis--Wisconsin. / Vita. Includes bibliographical references (leaves 103-115).

Thesis (M.S.)--University of Wisconsin--Madison, 1960. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves [23]-[25]).

Deuterium nmr is used to investigate the temperature dependence of the orientational order of small amounts of perdeuterated potassium carboxylates of differing chain lengths dissolved as guests in the protiated host potassium paimitate. Additionally, samples containing lipids of a single chain length equal to that of each guest are studied for comparison. Long chain guests have the same orientational order as the host up to the 15th position, while the rest of the chain is orientationally disordered. Short chain guests are restricted inside the host and there is less interaction of the polar head with water than in the single chain length samples. Phase separation involving a rapid exchange of molecules between a lamellar phase and a possibly isotropic phase yields unexpectedly low splittings for the short chain guests at lower temperature and with higher water content. / Science, Faculty of / Chemistry, Department of / Graduate

In recent years biochemical studies have played an important role in research into the pathogenesis of ischaemic heart disease. A large number of these studies have been concerned with the relationship between serum lipids and ischaemic heart disease (I.H.D.), which has been defined by the World Health Organization (1957) as "the cardiac disability, acute and chronic, arising from reduction or arrest of blood supply to the myocardium in association with disease processes in the coronary arterial system".

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Cardiovascular Disease (CVD) is the leading cause of death worldwide, a disease which has atherosclerosis at the centre of its pathology and is also linked to obesity. Atherosclerosis is known to be a chronic inflammatory disease with immune system activation. This immune activation is linked to increased postprandial triglyceride (TG) concentrations, which are an independent risk factor for the development of CVD. This thesis has demonstrated that a single bout of high intensity interval exercise (HIIE) is a low energy-expenditure (EE) and relatively time-efficient method of attenuating postprandial TG after high fat meals (HFMs). The mechanism underlying this reduction in postprandial TG is likely to be lipoprotein lipase (LPL) mediated, rather than via altered hepatic metabolism. To support this assertion the current thesis demonstrated that plasma β-hydroxybutyrate concentrations were unchanged while LPL dependent TG rich lipoprotein (TRL)-TG hydrolysis (LTTH) was increased the day after HIIE was performed. The beneficial effects do not remain when HFMs are consumed on a second day after HIIE. Furthermore HIIE does not alter select markers of postprandial immune cell activation, assessed via flow cytometric measurement of leukocyte CD11b and CD36 expression. Similarly HIIE had no effect on postprandial soluble adhesion molecule expression (sICAM-1 and sVCAM-1). On the other hand, HIIE was shown to attenuate the postprandial rise in markers of oxidative stress (plasma TBARS and protein carbonyls). In a separate study, substrate metabolism was studied in vitro in C2C12 muscle cells. Recent work has, in several mouse models, shown that reduced citrate synthase (CS) activity may be important in obesity resistance and also lower plasma TG levels, via an increase in fatty acid (FA) oxidation. However, in the current thesis, when CS activity was reduced in C2C12 muscle cells via lentiviral transduction, FA oxidation was in fact reduced when cells were incubated with glucose (5mM) and palmitate (0.8mM), for both 2 and 24 hours. These findings highlight the importance and ambiguity of CS's role as an intracellular metabolic modulator in muscle. This also warrants further research into how muscle citrate metabolism may be manipulated to improve substrate metabolism in diseases such as obesity, diabetes and CVD.