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- All Subjects: Organometallic compounds
- Creators: Mayol-Kreiser, Sandra
Description
ABSTRACT
Objective: This research examined the effectiveness of a weight loss diet incorporating high protein pasta and breakfast cereal products as compared to a weight loss diet using conventional versions of gluten-free pasta and breakfast cereal.
Design: In a 6-week parallel-arm food trial (representing the first phase of a 12-week cross-over trial), 26 overweight and obese (Mean BMI 43.1 ± 12.4 kg/m²) participants, free of related comorbidities, were randomly assigned to the Zone diet (~29% energy intake from protein) or a control diet (~9% energy from protein). Participants were included in the trial if they satisfied the criteria for elevated risk for metabolic syndrome (top half of the TG/HDL ratios of all who were tested). Participants were instructed to eat prepared meals (total of 7 cereal packets and 14 pasta meals weekly) that included patented food technologies for the Zone diet and commercially available gluten-free rice pasta and a conventional name brand boxed cereal for the control diet. Body composition was measured with a bioelectrical impedance scale at weeks 1, and 6. Food records and diet adherence were recorded daily by the participants.
Results: Both the Zone and control diets resulted in significant weight loss (-2.9 ± 3.1 kg vs. -2.7 ± 2.6 kg respectively) over time (p = 0.03) but not between groups (p = 0.96). Although not statistically significant, the Zone diet appears to have influenced more weight loss at trial weeks 3, 4, and 5 (p = 0.46) than the control diet. The change in FFM was significant (p = 0.02) between the Zone and control groups (1.4 ± 3.6 kg vs. -0.6 ± 1.5 kg respectively) at week-6. Study adherence did not differ significantly between diet groups (p = 0.53).
Conclusions: Energy-restricted diets are effective for short-term weight loss and high protein intake appears to promote protein sparing and preservation of FFM during weight loss. The macronutrient profile of the diet does not appear to influence calorie intake, but it does appear to influence the quality of weight loss. Other measures of body composition and overall health outcomes should be examined by future studies to appropriately identify the potential health effects between these diet types.
Objective: This research examined the effectiveness of a weight loss diet incorporating high protein pasta and breakfast cereal products as compared to a weight loss diet using conventional versions of gluten-free pasta and breakfast cereal.
Design: In a 6-week parallel-arm food trial (representing the first phase of a 12-week cross-over trial), 26 overweight and obese (Mean BMI 43.1 ± 12.4 kg/m²) participants, free of related comorbidities, were randomly assigned to the Zone diet (~29% energy intake from protein) or a control diet (~9% energy from protein). Participants were included in the trial if they satisfied the criteria for elevated risk for metabolic syndrome (top half of the TG/HDL ratios of all who were tested). Participants were instructed to eat prepared meals (total of 7 cereal packets and 14 pasta meals weekly) that included patented food technologies for the Zone diet and commercially available gluten-free rice pasta and a conventional name brand boxed cereal for the control diet. Body composition was measured with a bioelectrical impedance scale at weeks 1, and 6. Food records and diet adherence were recorded daily by the participants.
Results: Both the Zone and control diets resulted in significant weight loss (-2.9 ± 3.1 kg vs. -2.7 ± 2.6 kg respectively) over time (p = 0.03) but not between groups (p = 0.96). Although not statistically significant, the Zone diet appears to have influenced more weight loss at trial weeks 3, 4, and 5 (p = 0.46) than the control diet. The change in FFM was significant (p = 0.02) between the Zone and control groups (1.4 ± 3.6 kg vs. -0.6 ± 1.5 kg respectively) at week-6. Study adherence did not differ significantly between diet groups (p = 0.53).
Conclusions: Energy-restricted diets are effective for short-term weight loss and high protein intake appears to promote protein sparing and preservation of FFM during weight loss. The macronutrient profile of the diet does not appear to influence calorie intake, but it does appear to influence the quality of weight loss. Other measures of body composition and overall health outcomes should be examined by future studies to appropriately identify the potential health effects between these diet types.
ContributorsJames, Andrew (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Shepard, Christina (Committee member) / Arizona State University (Publisher)
Created2015
Description
Cardiovascular disease has reached epidemic proportions resulting in its ranking as the number one cause of mortality in the Western world. A key player in the pathophysiology of vascular disease is oxidative stress due to free radical accumulation. This intervention study was conducted to evaluate any potential mediation of oxidative stress using a soil-derived organometallic compound (OMC) with suspected antioxidant properties. A 10-week study was conducted in male Sprague-Dawley rats (n = 42) fed either a high-fat diet (HFD) consisting of 60% kcal from fat or a standard Chow diet containing only 6% kcals from fat. Rats from each diet group were then subdivided into 3 subgroups (n = 6-10 each) that received 0.0 mg/mL, 0.6 mg/mL or 3.0 mg/mL OMC. Neither the diet nor OMC significantly changed protein expression of inducible nitric oxide synthase (iNOS) in isolated aortas. Plasma levels of the inflammatory marker, tumor necrosis factor alpha (TNFα) were below detection after the 10-week trial. Superoxide dismutase (SOD), a scavenger of the free radical, superoxide, was not significantly different following HFD although levels of SOD were significantly higher in Chow rats treated with 0.6 mg/mL OMC compared to HFD rats treated with the same dose (p < 0.05). Lipopolysaccharides (LPS) were significantly increased following 10 weeks of high fat intake (p < 0.05). This increase in endotoxicity was prevented by the high dose of OMC. HFD significantly increased fasting serum glucose levels at both 6 weeks (p < 0.001) and 10 weeks (p < 0.025) compared to Chow controls. The high dose of OMC significantly prevented the hyperglycemic effects of the HFD in rats at 10 weeks (p = 0.021). HFD-fed rats developed hyperinsulinemia after 10 weeks of feeding (p = 0.009), which was not prevented by OMC. The results of this study indicate that OMC may be an effective strategy to help manage diet-induced hyperglycemia and endotoxemia. However, further research is needed to determine the mechanism by which OMC helps prevent hyperglycemia as measures of inflammation (TNFα) and vascular damage (iNOS) were inconclusive.
ContributorsWatson, Deborah F (Author) / Sweazea, Karen L (Thesis advisor) / Johnston, Carol (Committee member) / Mayol-Kreiser, Sandra (Committee member) / Arizona State University (Publisher)
Created2018
Description
The search for highly active, inexpensive, and earth abundant replacements for existing transition metal catalysts is ongoing. Our group has utilized several redox non-innocent ligands that feature flexible arms with donor substituents. These ligands allow for coordinative flexibility about the metal centre, while the redox non-innocent core helps to overcome the one electron chemistry that is prevalent in first row transition metals. This dissertation focuses on the use of Ph2PPrDI, which can adopt a κ4-configuration when bound to a metal. One reaction that is industrially useful is hydrosilylation, which allows for the preparation of silicones that are useful in the lubrication, adhesive, and cosmetics industries. Typically, this reaction relies on highly active, platinum-based catalysts. However, the high cost of this metal has inspired the search for base metal replacements. In Chapter One, an overview of existing alkene and carbonyl hydrosilylation catalysts is presented. Chapter Two focuses on exploring the reactivity of (Ph2PPrDI)Ni towards carbonyl hydrosilylation, as well as the development of the 2nd generation catalysts, (iPr2PPrDI)Ni and (tBu2PPrDI)Ni. Chapter Three presents a new C-O bond hydrosilylation reaction for the formation of silyl esters. It was found the (Ph2PPrDI)Ni is the most active catalyst in the literature for this transformation, with turnover frequencies of up to 900 h-1. Chapter Four explores the activity and selectivity of (Ph2PPrDI)Ni for alkene hydrosilylation, including the first large scope of gem-olefins for a nickel-based catalyst. Chapter Five explores the chemistry of (Ph2PPrDI)CoH, first through electronic structure determinations and crystallography, followed by an investigation of its reactivity towards alkyne hydroboration and nitrile dihydroboration. (Ph2PPrDI)CoH is the first reported cobalt nitrile dihydroboration catalyst.
ContributorsRock, Christopher L (Author) / Trovitch, Ryan J (Thesis advisor) / Kouvetakis, John (Committee member) / Pettit, George R. (Committee member) / Arizona State University (Publisher)
Created2018
Description
Background: Research has found that nearly a quarter of the American population follows a gluten-free diet in some capacity, while only about 1% of the population is diagnosed with celiac disease. Although the amount of research-based evidence supporting any health benefits of a gluten-free diet in an individual without a gluten- related disorder is limited, the number of people claiming to follow a gluten-free diet continues to rise. Also, despite an increasing belief that gluten is harmful for health, the potentially undesirable effects of gluten substitutions used in gluten-free foods are largely unknown. Due to the protein network encapsulating starch granules, gluten is thought to lengthen the amount of time needed during starch digestion, thereby reducing postprandial glycemia. Therefore, it is predicted that breads containing gluten will produce a lower glycemic response compared to gluten-free breads. Aim: The aim of this study was to investigate the glycemic response of gluten-free bread made with different types of flour compared to bread made with gluten-containing wheat flour. Methods: This study involved a 3-week, randomized, single blind crossover study in which 17 healthy individuals were asked to consume a different type of bread each week, 2 of which were gluten-free. Blood glucose was taken by finger prick at fasting as a baseline measurement, then for 2 hours after bread consumption in 30-minute increments. Results: Across the three groups, there was no significant difference in iAUC values after 120 minutes (p=0.192 ). The greatest mean was seen in the gluten-containing bread (145.3 ± 82.6), then the gluten-free bread made with rice flour (125.5 ± 62.8), and lastly the gluten-free bread made with potato and fava bean flour (112.4 ± 64.5). Conclusion: The inconsistent results of this study compared to previous, similar studies suggests that the postprandial glycemic response of gluten-free products can not be generalized as a whole, but instead is dependent on the type of product and the ingredients used to replace the gluten. Although the results did not show a significant difference, it does argue against the belief that gluten-free products are invariably better for health in the general, non-gluten sensitive population.
ContributorsWaznik, Lauren LaRue (Author) / Johnston, Carol (Thesis advisor) / Mayol-Kreiser, Sandra (Committee member) / Dixon, Kathleen (Committee member) / Arizona State University (Publisher)
Created2019