While replacement of dietary saturated fat with unsaturated fat has been advocated to reduce cardiovascular disease risk, diets high in polyunsaturated fatty acids (PUFA) could increase low density lipoprotein (LDL) susceptibility to oxidation, potentially contributing to the pathology of atherosclerosis. To assess in vivo lipid peroxidation and susceptibility, of LDL surface and core lipids to ex vivo oxidation, in women consuming increased amounts of specific unsaturated fatty acids, 15 postmenopausal women took daily supplements of sunflower oil providing 12.3 g/day of oleate, safflower oil providing 10.5 g/day of linoleate, and fish oil providing 2.0 g/day of eicosapentaenoate (EPA) and 1.4 g/day of docosahexaenoate (DHA) during a crossover trial. Plasma F₂-isoprostanes (F₂-isoP), malondialdehyde (MDA), and thiobarbituric acid reacting substances (TEARS) were measured to assess lipid peroxidation in vivo. Ex vivo oxidation of LDL was monitored by measuring the formation of phosphatidylcholine hydroperoxides (PCOOH) and cholesteryl linoleate hydroperoxides (CE18:200H) during coppermediated oxidation. Plasma free F₂-isoP and MDA concentrations were lower after EPA/DHA supplementation than after oleate (P = 0.001, F₂-isoP and 0.02, MDA) and linoleate supplementation (P = 0.04 for both F₂-isoP and MDA). However, plasma TBARS concentrations were higher after EPA/DHA than after oleate (P = 0.001) and linoleate supplementation (P = 0.0004). During LDL oxidation, the lag phase for PCOOH formation was shorter in EPA/DHA- than oleate- (P = 0.0001) and linoleate-enriched LDL (P = 0.002), while the lag phase for CE18:200H was shorter in EPA/DHA- than oleate- (P = 0.01) but not linoleate-enriched LDL. The maximal rate of PCOOH formation was lower in EPA/ DHA- than linoleate- (P = 0.007) but not oleate-enriched LDL, while the maximal rate of CE18:200H formation was lower in EPA/DHA- than oleate- (P = 0.03) and linoleate-enriched LDL (P [less than or equal to] 0.0001). The maximal concentrations of PCOOH and CE18:200H were lower in EPA/DHA- than oleate- (P [less than or equal to] 0.05) and linoleate-enriched LDL (P [less than or equal to] 0.01). Oleate-enrichment generally decreased the oxidative susceptibility of LDL surface and core lipids, while EPA/DHA-enrichment did not increase LDL oxidative susceptibility compared to linoleate-enrichment. This study emphasizes the need for more than one relevant assay of in vivo lipid peroxidation. / Graduation date: 2000

The purpose of this study was to examine the effect of extreme exercise on vitamin B-6 metabolism and urea nitrogen. Nine men and five women completed two 5-day trials; Trial 1 (T1) included a 50-km ultramarathon on day 4 and during Trial 2 (T2) subjects were "inactive" on day 4. During both trials, subjects consumed a diet providing men 2.0 and women 1.5 mg of vitamin B-6. With the exception of the ultramarathon, T1 activity was replicated during T2. Twenty four-hour urine collections were completed and blood was drawn pre-race (pre), mid-race (mid), post-race (post) and 60 minutes post race (P-60). On the inactive, day blood was drawn at the same intervals. Plasma was analyzed for pyridoxal 5'-phosphate (PLP), pyridoxal, 4-pyridoxic acid (4-PA), urea nitrogen (PUN), creatinine, albumin, glucose, and lactate concentration and alkaline phosphatase activity. Urine was analyzed for 4PA, creatinine, and total urinary nitrogen (TUN). During T1, compared to pre, plasma PLP concentration increased 17% at mid, decreased 5% by post, and 19% by P-60. During T2, plasma PLP concentration decreased 13% pre to P-60. During T1, plasma 4-PA concentration increased 135% and the percent dietary vitamin B-6 that was excreted as urinary 4-PA the day of the ultramarathon was higher than that excreted the day before and the day after. During T1, from pre to post mean PUN concentration increased 36.9%, and the average rate ofincrease from pre to mid, mid to post, and post to P60 was 0.5, 1.75, and 2 mg/dL/hour, respectively. During T1 on days 3, 4, and 5,88%, 100%, and 95% of nitrogen intake was excreted in the urine compared to 86%, 83%, and 84% for the same days during T2. The day of the ultramarathon, 24-hour TUN excretion was 2 g higher than the previous day. Extreme exercise of greater than six hours initially increases the plasma concentration of PLP but ultimately results in a significant decrease in plasma PLP, an increase in plasma 4-PA, and an increase in percent of dietary vitamin B-6 (as 4-PA) excreted in the urine. Additionally, the rate of change in PUN inoeases as duration increases. / Graduation date: 2001

This investigation was conducted to determine the effect of estrogen replacement therapy (ERT) on vitamin B-6 status of postmenopausal women. Nineteen postmenopausal women served as subjects. Nine (54.7 + 4.7 years) were taking ERT (experimental group); ten (56.8 + 2.3 years) were not (control group). For three consecutive days, subjects recorded their dietary intake and collected their 24-hour urine specimens. On the fourth day, a fasting blood sample was drawn from the subjects. The dietary intake of vitamin B-6, as well as the concentration of total vitamin B-6 in plasma (PB6; and urine (UB6) were measured. PB6 and UB6 were determined by a microbiological method with Saccharomyces uvarum as the assay organism. The mean age, height, hematocrit and hemoglobin values were similar for the two groups. The experimental group was significantly heavier than the control group (p<0.05). The experimental group had a lower mean PB6 than the control group: 47.7 ± 19.7 nmol/L vs. 56.2 + 20.6 nmol/L. These means were not significantly different (p=0.05). PB6 was positively correlated with dietary vitamin B-6 intake (p=0.0001) and vitamin B-6 to protein ratio (p=0.0021). When the means were adjusted for dietary vitamin B-6 and the vitamin B-6 to protein ratio, the mean PB6 of the experimental group (42.7 nmol/L) was significantly lower than that of the control group (60.6 nmol/L) (p<0.05). PB6 was not positively correlated with either age (r=0.20) or the vitamin B-6 dietary history score (r=0.15). UB6 was similar for the two groups. UB6 correlated positively with daily dietary intake of vitamin B-6 (r=0.51, p<0.05) and the ratio of vitamin B-6 to protein (r=0.47, p<0.05), UB6 was not significantly correlated to urine volume (r=0.05). The mean daily intakes of vitamin B-6 and protein were similar for the two groups. One of the 19 subjects had a vitamin B-6 intake that was less than 67 percent of the RDA. Most subjects' (89%) intake of vitamin B-6 was adequate when the ratio of 0.016 mg of vitamin B-6 per g of protein was used as the standard. / Graduation date: 1990

Preliminary data from studies in rodents suggests time-dependent associations between dietary LC n-3 PUFA and hepatic levels of the enzyme soluble epoxide hydrolase (sEH), which regulates the metabolism and availability of epoxyeicosatrienoic acids (EET).  EET are cytochrome P450 epoxygenase products of arachidonic acid associated with  lower blood pressure, decreased inflammatory response and inhibition of blood coagulation. To further investigate the association between LC n-3 PUFA and sEH, ApoE^-/^- mice were fed a high-fat high-cholesterol diet supplemented with either fish oil (EPA + DHA) or DHA or HOSF (all 2% w/w) for 10 weeks and livers and aortic roots were collected on day 2 and weeks 1, 2, 4 and 10.  Proteomics analysis showed an overall decreasing effect of fish oil (but not DHA) supplementation on hepatic protein levels of sEH compared to the control throughout the intervention period (<i>P</i> &lt; 0.05).  Neither fish oil nor DHA intervention affected atherosclerotic plaque size in the aortic root. We also examined how dietary supplementation with 1 g/day EPA or 1 g/day DHA for 10 days affects platelet sEH levels and platelet aggregation compared to 1 g/day HOSF (control) in healthy volunteers in a double-blind, placebo-controlled, cross-over trial.  We found that DHA decreased platelet aggregation by 10% (<i>P =</i> 0.04) and EPA also inhibited ADP (5 μM)-induced platelet aggregation by 14% compared to the control group but this effect did not reach statistical significance due to high variability between subjects.  EPA decreased platelet sEH levels by 25% (not significant), whereas DHA had no effect.  We also attempted to optimize a method for measuring EET in plasma and platelets.  However, the rapid conversion of EET to other compounds and their low concentration in tissues prevented us from optimizing such a method within the time limits of the project.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Digitized by Kansas Correctional Industries

Photocopy of typescript. / Digitized by Kansas Correctional Industries

Includes bibliographical references (leaves 196-220) Studies the growth, body composition, feed intake of grazing animals, the use of anabolic agents, fatty acid composition of ruminants fats; and, the effect of saturated fat on human health.

Whole fruits, grains and vegetables contain thousands of potential disease-fighting, healthpromoting nutrients. These foods play a critical role in bowel function, especially in the elderly. Strong epidemiological evidence has shown that greater amounts of crude dietary fibre are associated with a lesser prevalence of constipation and other gastrointestinal disorders. Constipation usually presents as a variety of symptoms, including reduced frequency of defaecation and impacted forms of stools and/or increased effort required to defaecate. Constipation is a problem that could affect any person at any time in his or her life, but in the elderly is more prevalent.Although anecdotal reports and dietary advice have suggested the use of kiwifruit as a laxative in humans, there are, at present no data available to support this. Kiwifruit is reported as the most nutrient-rich of the top 27 fruits eaten in the world today. The laxative property of kiwifruit could provide a natural remedy for constipation and would be cheaper than the laxatives on the market.Objective: The main objective of this study was to investigate if kiwifruit can act as a laxative, especially in elderly people.Study Design and Methods: This study was carried out in two stages, as a pilot and then a main study. In the pilot study, 71 participants (aged 18 - 50y) were divided into Group I and Group II. Group I made no changes to their normal diet for a six weeks period, while Group II were asked to add one kiwifruit for every 30kg body weight per day to their diet for a six week period. After the six weeks, the two experimental groups crossed over, maintaining the dietary regime followed by the other group for a further six weeks. So each subject was his or her own control. Daily recording of the frequency and characteristics of the stool were made by the participants in a diary. In the main study, 42 participants (aged 60 years and over) carried out the same dietary regime as the pilot study subjects. Elderly subjects of Group I made no changes to their diet, but was asked to record their daily frequency and characteristics of their stool for 3weeks. Group II subjects ate one kiwifruit for every 30kg body weight per day for a period of 3weeks. After the three weeks period, the two groups crossed over.Results: It was found from the pilot study that kiwifruit consumption was associated with significant softening of the stool (P<0.001); a significant increase in bulking of the stool (P=0.034) and the ease of bowel movement was improved (P<0.001). For the main study, kiwifruit consumption also showed softening of the stool (P<0.001) and the ease of bowel movement was improved (P<0.001), there was a slight but significant increase in bowel frequency (P=0.012) and the bulking of stool (P=0.002).Conclusion: The results from this study provide evidence that consumption of kiwifruit enhances laxation and that bowel function can be improved through changes in diet, both for younger and elderly people.

There is much interest in the nature and quality of the diet consumed by adolescents. To determine whether there are significant associations between diet and gain in height and weight in this age group, the present study analysed data on food intake and weight and height obtained on three occasions over a 30-month period from a total of 326 adolescents aged between 12 and 15 years. Information on sociodemographic and other lifestyle factors, including an indicator of physical activity, was also obtained. Energy intake was found to be a significant positive predictor of both height and weight gain. In addition intake of fat, calcium and riboflavin were found to be significant positive predicators of height gain and intake of carbohydrate and starch significant positive predictors of weight gain. After controlling for energy intake only riboflavin approached significance as a positive predictor of height gain. A food group analysis identified intake of dairy foods as a significant predictor of height gain. Although statistically significant the dietary predictors explained only a small proportion of the variability in height and weight (≤3.5%). Given the difficulties in obtaining complete dietary records from this age group and the generally adequate nature of the diet in the study group, the small proportion of height and weight gain explained by diet is not unexpected. Nevertheless the nutrient predictors identified are consistent with nutrient requirements for growth during adolescence and highlight the importance, for this age group, of an adequate intake of nutrients specifically provided by dairy foods. Few significant associations were found between growth rates and the sociodemographic and the lifestyle factors measured in this study. The ethnic diversity of the study sample may have contributed to this outcome.