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EFFECT OF DIETARY TRANS FATTY ACIDS ON MUTAGENESIS OF KNOWN CARCINOGENS (ISOMERS, AMES ASSAY, HYDROGENATED)Unknown Date (has links)
The effects of feeding rats a fat which contained approximately 46.6% trans fatty acids (trans fat) on the mutagenic potential of 2-aminofluorene (AF), benzo(a)pyrene (BP), dimethylbenz(a)anthracene (DMBA), and azoxymethane (AOM) were evaluated in the Ames assay. The corresponding control fat (cis fat) had a similar fatty acid composition, consisting only of cis isomers. Since both the cis and trans fats contained approximately 40% saturated fatty acids a comparison was made between these two types of fat and corn oil. All three fats were incorporated into a high fat, 20%, and moderate fat, 5%, diet and fed to male Sprague-Dawley rats for three weeks. / The effects of the level and type of fat on mutagenicity varied with the specific mutagen under investigation. The 20% level of fat whether cis, trans, or corn oil resulted in greater mutagenic activity with BP and AF when compared to the 5% level. At the 5% fat level the results for BP and AF were in conflict. The 5% trans fat resulted in the highest mutagenic response for AF, while the 5% corn oil resulted in the highest mutagenic response for BP. The trans fat produced a higher mutagenic potential at the 5% level with AF than the 5% cis fat, but at the 20% level no difference was found between the cis and trans fats. These findings indicate that not only does the quantity and type of fat alter the mutagenic response found in the Ames/Salmonella microsome assay, but also the effect of the fat in the assay varies with the mutagen tested. / Only with DMBA did type of fat affect the positive and negative outcomes of the assays. DMBA gave a positive response only in the assays using livers from rats fed corn oil diets, with no differences between the 5% and 20% level of corn oil. No positive responses were found with DMBA in the assays with liver homogenates from rats fed trans fat or cis fat. This suggests that DMBA required a moderate to high level of polyunsaturated corn oil to produce a positive mutagenic response. / Source: Dissertation Abstracts International, Volume: 47-03, Section: B, page: 0871. / Thesis (Ph.D.)--The Florida State University, 1986.
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Genetic predilection and dietary experience: Their interactive contributions to sweet tastant response phenotypes in mice (Mus domesticus)Unknown Date (has links)
Genetic and environmental contributions to the ingestion of sweet tastants (sucrose, glucose + saccharin) were examined using two complete diallel crosses of four inbred mouse strains, each replicated four times. Diallel sets differed only in regard to prior gustatory experience. One diallel set had a life history of 10$\sp{-1}$M sucrose solution as its sole source of fluid and the second set had water. In adulthood and while maintained on their respective treatment regimens, food and fluid intakes were measured for individuals of both sets. Mice were then subjected to a descending concentration series of sucrose solution versus water 48-h, two-bottle preference tests, followed by a single preference test using glucose + saccharin. Results indicated significant effects of both rearing history and genetic constitution on a variety of ingestive phenotypes. Relative to the number of food calories ingested by water-reared mice, those ingested by sucrose-reared mice decreased in direct compensation for calories obtained from fluid. Across multiple sucrose concentrations, sucrose-reared mice ingested and preferred sucrose significantly more than water-reared mice. This treatment effect, apparent for sucrose concentrations not yet reported as detectable by mice, also generalized to a novel sweet tastant, glucose + saccharin. Treatment effects also largely depended on mouse genotype. Genetic influences on sweet fluid ingestion were indicated as predominantly additive. For sweet preferences, low levels of dominance were detected among sucrose-reared mice only; for glucose + saccharin intake, dominance levels were higher for both treatment groups. Indications of large additive genetic effects, in combination with no, low, and/or ambidirectional dominance are consistent with an interpretation of an evolutionary history of stabilizing selection for sweet fluid / preferences and ingestions. Results indicating environmental modification of genetic predilections for sweets emphasizes the interactive contribution of genotype and environment to sweet ingestion phenotypes. / Source: Dissertation Abstracts International, Volume: 50-03, Section: B, page: 0866. / Major Professor: Glayde Whitney. / Thesis (Ph.D.)--The Florida State University, 1988.
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Selected physiological effects of caffeine at low and moderate intensities of walking exerciseUnknown Date (has links)
The purpose of this study was to examine the influence of caffeine (5 mg/kg body weight) on metabolism and cardiorespiratory variables during walking exercise at low and moderate aerobic intensities. In addition, caffeine's effect on perception of effort during walking was studied. Eight normotensive, sedentary (VO2max: 39.64, SD $+/-$ 3.05), male nonsmokers (age 21-28) with a habitual caffeine intake of less than 300mg/day participated in four 60-min treadmill walking sessions with and without prior caffeine. Two of these trials were performed at self-selected "normal" walking speed (2.90 mph, SD $+/-$ 0.12), corresponding to 30% VO2max exercise intensity; the other two tests were performed at self-selected "fast" walking speed (3.93 mph, SD $+/-$ 0.12), corresponding to a 50% VO2max work load. The order of trials was randomized and counterbalanced. The study was performed using a placebo double-blind design and data were analyzed using repeated measures ANOVA with each subject serving as his own control. / Caffeine intake 60 min prior to walking exercise increased pre- and post-exercise FFA, glycerol, and lactate concentrations (p $<$ 0.05). Walking exercise by itself raised serum levels of FFA and glycerol (p $<$ 0.05). Blood glucose concentration tended to be higher in caffeine trials (p = 0.06) and were lower post-exercise (p $<$ 0.05). Cardiorespiratory influences of caffeine included a rise in systolic blood pressure, pulse pressure, and minute ventilation during walking (p $<$ 0.05). Walking intensity level selectivity influenced energy substrate metabolism and cardiorespiratory responses. Significant time effects across the 60-min walking duration were noted for HR, RER, and the relative and absolute contribution of carbohydrate and fat for energy (p $<$ 0.05). The influence of caffeine on the perception of subjective effort during walking was statistically nonsignificant (p = 0.08). / It is concluded that ingestion of 5 mg/kg caffeine selectively influences metabolic and cardiorespiratory responses during walking exercise at 30% and 50% VO2max. The present data do not suggest that caffeine enhances the fat reducing potential of prolonged walking exercise. / Source: Dissertation Abstracts International, Volume: 50-10, Section: B, page: 4390. / Major Professor: Emily M. Haymes. / Thesis (Ph.D.)--The Florida State University, 1989.
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Meal composition, snacking patterns and their effects upon moodUnknown Date (has links)
Female college freshmen were designated as either Carbohydrate Cravers or Mixed Snackers according to their responses to a survey of snacking patterns. In a between-groups design, their moods and their ratings of the desirability of various foods were assessed immediately before and two hours after the consumption of either a high-protein meal, a high-carbohydrate meal equal in calories to the protein meal, or a mixed carbohydrate-protein-fat meal that was higher in calories than the other two. Compared to Mixed Snackers, Carbohydrate Cravers showed a significant preference for high-carbohydrate foods over high-protein foods pre-meal, but the two groups did not differ significantly on pre-meal mood measures in a multivariate analysis of variance. They also did not differ significantly on pre-meal measures of hunger, dietary disinhibition, or dietary restraint. / On the post-meal measures, Carbohydrate Cravers did not differ significantly from Mixed Snackers on the mood measures nor on the food desirability ratings. Meal composition had no effect upon mood, but it did affect food ratings, albeit in unexpected ways: post-meal ratings of high-carbohydrate foods by subjects who had received the high-carbohydrate meal did not differ significantly from similar ratings of subjects who had received the other two meals, but ratings of protein foods by the high-carbohydrate meal subjects were significantly higher than similar ratings from the other two groups. It was speculated that the mostly liquid composition of the high-carbohydrate meal, and/or its lack of fat, may have made it less satisfying or satiating than the other two meals. / Results of this study are discussed in terms of their implications for two opposing theories of "Carbohydrate Craving". / Source: Dissertation Abstracts International, Volume: 52-03, Section: B, page: 1701. / Major Professor: Richard Hagen. / Thesis (Ph.D.)--The Florida State University, 1991.
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The effect of nutrition education on the snack food behavior of public elementary school children in Costa RicaUnknown Date (has links)
The snacking behaviors of students and the effect of a nutrition education unit (NEU) on third graders in Costa Rica were investigated. After a pilot phase, eight schools from San Jose were randomly selected. School sodas (snack bars or stores) were described using nonparticipant-observation techniques. The survey sample (N = 105) consisted of soda managers and teachers and students from grades three and six who were interviewed. Third graders also completed 24-hour food recalls. / Chips, carbonated beverages, cookies, fruits, and confectionery were the most frequently consumed snacks at the sodas. Third graders were more likely to bring a snack bag from home to school than sixth graders. The diet of third graders was high in total fat, saturated fat, sugar, caffeine, and low in fiber. Snacks from the soda contributed one-third of the daily sugar intake. / Thereafter, a four-session NEU on "choosing nutritious snacks at the soda" was developed. The NEU included demonstrations, skits, slides, games, stories, oath, and certificate of completion. It was tested with 109 third graders at two purposively-selected schools in San Jose. Students were randomly selected and assigned to groups following Solomon's three group experimental design. Groups were equivalent in size, age, gender composition, academic performance, and socioeconomic status. Written exam scores and food coupon purchases were used as the two pre- and-posttest methods. / The differences in mean exam scores between groups were highly statistically significant at posttest (F = 46.15, p $<$ 0.0001, $\omega\sp2$ = 0.608). Treatment groups selected half as many non-nutritious and three times as many nutritious snacks from the soda as did control I groups. / These findings suggest that a four-session NEU may have a meaningful and positive short-term effect on the snack food behaviors of third graders. The results further indicate that the school soda can function as an influential learning lab and as a nutritional alternative to meeting the RDAs of elementary students in Costa Rica. / Source: Dissertation Abstracts International, Volume: 52-10, Section: B, page: 5199. / Major Professor: Ruth E. Pestle. / Thesis (Ph.D.)--The Florida State University, 1991.
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The effect of walking duration on recovery metabolic rate and fuel utilization in moderately obese femalesUnknown Date (has links)
To examine the effects of walking duration on excess post exercise oxygen consumption (EPOC), recovery substrate availability and fuel utilization, nine overfat (38.5 $\pm$ 2.4%) females completed treadmill walking sessions of 30, 45, 60, 75 and 90 minutes. Oxygen consumption (VO$\sb2$) and respiratory exchange ratio (RER) were continuously monitored by open circuit spirometry for 30 minutes before (rest) and 60 minutes following (recovery) each walking session. Resting and one-hour recovery venous blood was assayed for free fatty acid (FFA) and glycerol concentrations. Repeated measures ANOVAs were utilized for data analysis with Newman-Keuls' post-hoc employed to locate significant differences (p $\leq$ 0.05) between means. / Walking significantly elevated recovery VO$\sb2$ by 9.7%. Despite a non-significant walking duration effect, VO$\sb2$ at one hour of recovery following 30, 45, 60, 75 and 90 minutes of walking was 0.5%, 10.0%, 9.5%, 10.0% and 19.0% higher than pre-exercise rest. EPOC following 30 minutes of walking was significantly shorter in duration (minutes) and smaller in magnitude (net O$\sb2$ consumed) than for all other walking durations. Magnitude of EPOC was also significantly smaller for the 45 than the 90 minute walk. / Recovery concentrations of FFA were significantly elevated above rest following walking durations of 60, 75 and 90 minutes, while differences in rest and recovery glycerol concentrations were not significant. Respiratory exchange ratios at one-hour of recovery following both the 75 and 90 minute walks were significantly lower than respective pre-exercise resting RERs and significantly lower than recovery RERs following 30 and 45 minutes of walking. One-hour post-exercise, utilization of fat was elevated above rest by 5.4% (30 minute walk), 6.4% (45 minute walk), 9.4% (60 minute walk), 15.9% (75 minute walk) and 16.8% (90 minute walk). / A minimum walking duration of 45 minutes is required for sedentary overweight females before significant increases in recovery oxygen consumption and fat utilization occur. Recovery rates of oxygen consumption and fat utilization are further optimized as walking duration is extended to 90 minutes. Recommendations and statements concerning recovery and weight loss benefits of walking should consider these duration effects. / Source: Dissertation Abstracts International, Volume: 52-03, Section: B, page: 1273. / Major Professor: Robert J. Moffatt. / Thesis (Ph.D.)--The Florida State University, 1991.
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Diet and the risk of cardiovascular disease among U.S. adultsJanuary 2000 (has links)
Objective. To examine the relationships between dietary intake of fruits, vegetables, legumes, folate and potassium and the incidence of and mortality from cardiovascular disease Methods. The study sample consisted of participants in the National Health and Nutrition Examination Survey I Epidemiologic Follow-up Study (NHEFS) who were free of cardiovascular disease at baseline examination in 1971--1975 and received a dietary assessment including a 24-hour dietary recall and food frequency questionnaire. Folate intake was calculated using ESHA Food Processor software while other nutrients were calculated by NCHS at baseline. Intraclass correlation coefficients were above 0.90 for most nutrients, indicating strong agreement between the ESHA and NCHS nutrient databases. The relationship between diet and cardiovascular disease was examined using Kaplan Meier and Cox proportional hazards methods for time-to-event data Results. Frequency of fruit and vegetable consumption was inversely related to the incidence of stroke and mortality from stroke, coronary heart disease, cardiovascular disease and all causes. Intake of fruits and vegetables at least 3 times per day compared to less than once per day was associated with a 29% lower risk of stroke, 43% lower stroke mortality, 25% lower coronary heart disease mortality, 28% lower cardiovascular disease mortality, and 15% lower all cause mortality, after adjustment for established cardiovascular disease risk factors. Legume consumption was inversely associated with incidence of coronary heart disease and cardiovascular disease, after adjustment for the same cardiovascular disease risk factors. Dietary intake of folate and potassium were inversely related to the risk of stroke. Compared to persons consuming <136 mug folate/day, those consuming ≥300.6 mug folate/day had a 21% lower risk of stroke and 14% lower risk of cardiovascular disease, after adjustment for important risk factors. Dietary potassium intake may be inversely related to risk of stroke in a non-linear (threshold) manner. Persons consuming ≥34.6 mmol potassium/day were 27% less likely to experience a stroke than persons consuming less potassium per day after adjustment for established cardiovascular disease risk factors and dietary factors Conclusion. These findings suggest that increasing consumption of fruits, vegetables, legumes, potassium, and folate may reduce the risk of cardiovascular disease in US general population / acase@tulane.edu
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The effects of caffeine on exercise-induced changes during high-intensity, intermittent exerciseUnknown Date (has links)
The widespread popularity of both sports and caffeine, the caffeine ban in Olympic activities, the lack of understanding of the physiological and psychological effects of caffeine on high-intensity, intermittent exercise, all indicate the need for more definitive information concerning the caffeine exercise relationship. Although it is difficult to assess the metabolic effects of sports under field conditions, similar metabolic and circulatory modifications can be produced by interval exercise on the cycle ergometer (Keul, 1971). The purpose of this study was to determine the influence of caffeine treatment upon the serum free fatty acid and glycerol, blood glucose and lactate, as well as perceived exertion, oxygen cost, oxygen debt, and performance time values beyond those caused by three 30-minute/one-minute alternating work/rest intervals under a no caffeine treatment. / Eight, trained, male volunteers--ages 21 to 33 yrs.--served as subjects for this study. The exercise level for the high-intensity interval protocol was set at 85 to 90 percent of the maximal aerobic capacity determined by performance on a continuous cycle ergometer test. Two ergometer performance tests were administered approximately one week apart. For one test subjects ingested 5 mg/kg of caffeine and for the other a placebo one hour before beginning pedalling at 70 RPM at 85 to 90 percent of their maximum aerobic power. / A double blind counterbalanced design was used. All metabolic and respiratory data were calculated using the Apple IIe Computer (REP-200B Data Acquisition System, Vacumetrics, Inc.). A two-factor Analysis of Variance with repeated measures and paired t tests were used to test all hypotheses (p $<$.05). / Caffeine significantly increased time to exhaustion, serum free fatty acids, post-exercise oxygen cost levels and lower post exercise glucose levels. These findings suggest that the caffeine-induced glycogen sparing appears to enhance performance time during high intensity intermittent exercise. This is evidenced by significantly greater fat mobilization, oxygen cost, and higher blood glucose levels under the caffeine treatment. / Source: Dissertation Abstracts International, Volume: 52-10, Section: B, page: 5200. / Major Professor: Emily M. Haymes. / Thesis (Ph.D.)--The Florida State University, 1991.
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Iron supplementation and malaria infection : results of a randomized controlled field trialGebreselassie, Hailemichael. January 1996 (has links)
No description available.
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Alterations in indices of oxidative stress and diabetes in type I diabetic rats on a low-carbohydrate diet and pycnogenolKamuren, Zipporah T. January 2006 (has links)
Thesis (Ph.D.)--Indiana University, Medical Sciences Program, 2006. / Source: Dissertation Abstracts International, Volume: 67-01, Section: B, page: 0197. Adviser: John B. Watkins, III. "Title from dissertation home page (viewed Feb. 21, 2007)."
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