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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

COMPARISON OF HAIR, URINE, AND SALIVA ZINC LEVELS BY ATOMIC ABSORPTION SPECTROPHOTOMETRY WITH TASTE ACUITY IN A SAMPLE OF INDEPENDENT ELDERLY PERSONS

Unknown Date (has links)
Thirty eight non-institutionalized persons, aged 60-84, provided tissue samples for hair, saliva sediment and supernatant, and urine zinc analysis and were tested for taste acuity using the triangle-dilution test. No correlation was found between taste acuity and the tissue measures of zinc. Hair zinc levels and salivary sediment levels were significantly correlated (r = .31, p < .05) in this sample. With respect to age, taste acuity as measured by a detection/recognition score was significantly correlated (r = -.28, p < .05) as were hair zinc levels (r = .43, p < .01). When assessing the zinc status of a population group, comparisons should be made only among similar age ranges and at least two parameters should be utilized for assessment. Salivary sediment and hair zinc were correlated in this sample but further research is needed to ascertain the response of these two parameters to decreasing levels of zinc in the diet. / Taste acuity measures were not correlated to tissue measures of zinc indicating for this sample, that taste acuity was not a valid functional measure of zinc status. Although decreased taste acuity has been defined as a symptom of zinc deficiency, its use in detecting marginal levels of deficiency, its use in detecting marginal levels of deficiency was not supported by this research. Taste acuity did correlate negatively with age indicating a decrease in taste acuity with increasing age for this sample aged 60-84 particularly in the sour taste modality. To further delineate this relationship, a large sample with a greater age variance is needed. / The assessment of zinc status remains a problem due to the scarcity of data and the numerous variables to be controlled. Before additional work in the relationship of zinc status to other parameters, more research in the zinc assessment methodology is critical. A single tissue parameter or a combination of two or more must be demonstrated to reflect zinc status and respond to dietary manipulation initially through animal studies and finally in various human populations. / Source: Dissertation Abstracts International, Volume: 43-10, Section: B, page: 3193. / Thesis (Ph.D.)--The Florida State University, 1982.
12

Inhibition of oxidation of erythrocytes in cigarette smokers by carotenoids and alpha-tocopherol

Unknown Date (has links)
The purpose of this study was to find the hematologic differences among smokers, exsmokers, and nonsmokers, and to determine the effects of beta-carotene, canthaxanthin, and alpha-tocopherol on the lipid peroxidation of erythrocytes exposed either to cigarette smoking or to chemically induced oxidation. / Thirty heavy smokers, 30 nonsmokers, age and sex matched, and 25 exsmokers participated in this study. Exsmokers in this study ceased smoking but used nicotine patches (22 mg/day) for 30 days. / No significant differences in age, sex, and height were shown. A significant difference in weight between nonsmokers and exsmokers was found (p $<$ 0.05). Cigarette smokers in this study had a higher concentration of total hemoglobin and more autoxidation of oxyhemoglobin to methemoglobin than nonsmokers which suggests that smokers may have high oxidative stress of red blood cells. However, the only significant difference found was in the concentration of oxyhemoglobin (p $<$ 0.05), not in total hemoglobin and methemoglobin. / Antioxidant activities of carotenoids and alpha-tocopherol were determined by measuring the concentration of malondialdehyde (MDA nmol/100 ml) and percent hemolysis of erythrocytes, in vitro methods. The erythrocytes of cigarette smokers had a significantly higher MDA concentration than the erythrocytes of nonsmokers, with or without induced oxidation. After 30 days of smoking cessation, the MDA concentration, not percent hemolysis, was decreased, but it was not statistically significant. / The addition of antioxidants to erythrocytes significantly decreased MDA concentration (p $<$ 0.05). When oxidation was induced by t-butylhydroperoxide canthaxanthin showed the highest antioxidant activity. In cigarette smokers, carotenoids appeared to be more effective antioxidants than alpha-tocopherol in reducing MDA formation in red blood cells. / In contrast to the results of the TBA test, no difference in percent hemolysis between smokers and nonsmokers was shown without induced oxidation. Carotenoids used in this study appeared to inhibit percent hemolysis of erythrocytes (p $<$ 0.05) while the effect of alpha-tocopherol on hemolysis was not statistically significant. / Source: Dissertation Abstracts International, Volume: 55-09, Section: B, page: 3827. / Major Professor: Natholyn D. Harris. / Thesis (Ph.D.)--The Florida State University, 1994.
13

THE CO-MUTAGENIC POTENTIAL OF TRANS-FATTY ACIDS IN THE METABOLISM OF BENZO(A)PYRENE, 2-ANTHRAMINE, 2-ACETYLAMINOFLUORENE AND 2-AMINOFLUORENE (BENZOPYRENE)

Unknown Date (has links)
The effects of the incorporation of trans-fatty acids in the diet of rats on the mutagenic potential of benzo(a)pyrene (BP), 2-aminofluorene (AF), 2-acetylaminofluorene (AAF) and 2-anthramine (AA) were evaluated in the Ames Assay incorporating rat hepatocytes and liver cell homogenates (S-9 fraction) as the metabolic activating systems. The hepatocytes and S-9 fractions were derived from Aroclor or BHT induced and non-induced animals fed the experimental and control diets, 45% to 55% and 0% trans-fatty acids of a 15% fat diet, respectively. / Benzo(a)pyrene, 2-acetylaminofluorene and 2-aminofluorene were mutagenic in the S-9 assays from Aroclor and BHT induced animals fed the control and trans-fatty acid diets. In the S-9 assays from non-induced animals fed the control and trans-fatty acid diets, benzo(a)pyrene and 2-acetylaminofluorene were weakly mutagenic. Aroclor was a more effective inducer of benzo(a)pyrene and 2-acetylaminofluorene mutagenicity than BHT. The effects of the inducers, Aroclor and BHT, on the mutagenic potential of 2-aminofluorene was negligible. / The effects of diet on mutagenesis were few. The mutagenic potential of benzo(a)pyrene was significantly decreased in the S-9 assays from Aroclor induced animals fed the trans-fatty acid diet when compared to S-9 assays from Aroclor induced animals fed the control diet. The mutagenic response from 2-acetylaminofluorene was significantly higher in S-9 assays from BHT induced animals fed the trans-fatty acid diet than S-9 assays from animals fed the control diet. In assays from non-induced animals, a higher concentration of 2-acetylaminofluorene was required for mutagenesis with S-9 from trans-fatty acid fed animals than S-9 from animals fed the control diet. / In the hepatocyte assays, benzo(a)pyrene, 2-anthramine and 2-aminofluorene did not produce a mutagenic response. Effects from the inducers Aroclor and BHT or diet on the mutagenicity of benzo(a)pyrene, 2-anthramine and 2-aminofluorene were not observed in the hepatocyte assay. The S-9 fractions were more effective than hepatocytes in the metabolic activation from benzo(a)pyrene and 2-aminofluorene. / Source: Dissertation Abstracts International, Volume: 44-10, Section: B, page: 3042. / Thesis (Ph.D.)--The Florida State University, 1983.
14

LEUCINE METABOLISM IN CIRRHOTIC PATIENTS WITH HEPATIC ENCEPHALOPATHY (STABLE ISOTOPES)

Unknown Date (has links)
Although rapid clearance of plasma leucine in patients with cirrhosis was previously reported by others, the metabolic fate of leucine is not known. The purpose of this study was to determine whether increased oxidation of or protein synthesis requiring leucine occurs in cirrhotic patients. Five control subjects and four subjects with cirrhosis were equilibrated on a baseline diet (0.6 g protein per kg ideal body weight IBW ) with sufficient nonprotein calories to preclude negative nitrogen balance. An additional four patients were equilibrated on the same type of diet with a higher protein level (0.75 g per kg IBW). Control subjects and the patients were then studied during continuous infusion of L- ('15)N, 1-('13)C leucine in the fasted state and, in the fed state, with a Propac diet (administered by nasogastric tube) which had the same distribution of energy nutrients as the baseline diets. Plasma levels of L- ('15)N, 1-('13)C , L- 1-('13)C and L- ('15)N leucine were measured during isotopic steady state by gas chromatography-mass spectrometry and fractional excretion of ('13)CO(,2) in breath samples were analyzed by isotopic ratio mass spectrometry. During the fasted and fed states leucine metabolism was measured to quantitate rates of nitrogen flux (Q(,N)), carbon flux (Q(,C)) and oxidation to carbon dioxide and water (C). From these measured values, protein breakdown (B), protein synthesis (S), deamination (X(,O)) and reamination (X(,N)) were calculated. Protein breakdown decreased (p < 0.05) during feeding in controls and patients on both protein levels. An increased protein level (0.75 g per kg IBW) did not significantly improve protein synthesis when compared to controls and cirrhotics at the lower protein level and led to increased leucine oxidation (p < 0.05). When the diet consisted of 0.75 g protein per kg IBW Q(,N), Q(,C), X(,N), X(,O), / and C increased (p < 0.05) when compared to controls and patients with cirrhosis on a diet of 0.6 g per kg IBW. Under the conditions of the experiments the results showed that protein synthesis and leucine metabolism were identical in controls and patients when both were fed a diet with 0.6 g protein/kg IBW and maintenance level of nonprotein calories. The data also showed that leucine metabolism can be quantitatively and reproducibly measured in subjects with cirrhosis. / Source: Dissertation Abstracts International, Volume: 46-09, Section: B, page: 3011. / Thesis (Ph.D.)--The Florida State University, 1985.
15

DETERMINATION OF OXIDIZED CHOLESTEROL COMPOUNDS IN COMMERCIALLY PROCESSED COW'S MILK (THIN-LAYER, GAS CHROMATOGRAPHY, MASS SPECTROMETRY)

Unknown Date (has links)
The purpose of this investigation was to determine whether commercial processing of cow's milk leads to cholesterol oxidation. Pasteurized whole milk, ultrahigh temperature milk, canned evaporated milk, skim milk and instant nonfat dry milk were purchased from a local supermarket. Fresh raw milk was obtained from an area farm. Thin layer chromatography (TLC) was used for the initial analysis of the unsaponified total lipid extracts of the samples. Sterols were isolated and eluted from chromatoplates for gas chromatography-mass spectrometry (GC-MS) analysis. TLC and GC data indicate the cholesterol in liquid milk is stable during commercial pasteurization, sterilization and evaporation and to further heating of the milk for 12 hours at 85(DEGREES)C. TLC data indicate the presence of 7-hydroxycholesterol in instant nonfat dry milk. However, GC-MS analysis did not resolve this compound. The results of this investigation suggest that the spray-drying process may catalyze cholesterol oxidation but further analytical and experimental investigation is required to confirm such a conclusion. / Source: Dissertation Abstracts International, Volume: 47-07, Section: B, page: 2842. / Thesis (Ph.D.)--The Florida State University, 1986.
16

A COMPARISON OF TWO MODES OF NUTRITION EDUCATION ON PRESCHOOLERS' NUTRITION KNOWLEDGE AND CONSUMPTION OF FOODS AT THE NOON MEAL (PLATE WASTE)

Unknown Date (has links)
This research investigated the effect of two nutrition education programs, one nutrient-based and the other action oriented, on the nutrition knowledge and plate waste of preschool children. The study population consisted of 89 preschool children aged four to five years who attended day care in Alachua County, Florida. / An education unit was presented to the children each day during the treatment period by the regular classroom teachers. The researcher provided all necessary education materials and instructed the teachers on the use of each unit. Daily plate waste observations were made at the noon meal for the pre-treatment, treatment and post-treatment periods. All centers followed the same four week cycle menu and repeated the cycle three times, once for each period. The NEAS Pre-Primary edition was used to assess changes in nutrition knowledge and nutrition attitudes. / Following the presentation of nutrition education both groups showed an increase in nutrition knowledge and nutrition attitudes as compared with pre-treatment scores. The positive changes were found to be significant only for the nutrient-based group, however. A significant decline in mean plate waste was noted for both groups between pre-treatment and post-treatment periods. Mean plate waste decreased by a total of 7.17 points for the action oriented group and 6.34 points for the nutrient-based group. Findings of this study suggest the need for further study regarding the effect of nutrition education on the eating behaviors of young children. / Source: Dissertation Abstracts International, Volume: 45-11, Section: B, page: 3470. / Thesis (Ph.D.)--The Florida State University, 1984.
17

DIETARY INTAKE AND ANTHROPOMETRIC MEASUREMENTS OF RURAL ECUADORIAN PRESCHOOL CHILDREN

Unknown Date (has links)
Dietary intake practices and anthropometric measurements for 66 rural Ecuadorian preschool children, aged 1 to 5 years, were studied. The total sample comprised two groups: 46 children who lived in Aloguincho and participated in a food supplement program and 20 children who lived in La Merced, where no nutritional intervention had occurred. / Anthropometric measurements were analyzed according to age, sex, and village of the child and the values obtained were compared to an appropriate reference standard. Mean measurements of height, weight, triceps fatfold, head circumference, arm circumference, arm muscle circumference, and arm muscle area were similar for children, by age and sex, in both villages. For all of the anthropometric measurements, there were significant differences, as expected, between the age groups in each village. / Energy and nutrient intakes of the children in both villages were evaluated by using the 24-hour recall and the food frequency methods. Mean intakes of energy, protein, calcium, iron, thiamin, riboflavin, niacin, vitamin C, and vitamin A were compared to the Recomendaciones Nutricionales (recommended intake levels) of Ecuador to determine the nutritional adequacy of the diets. / Mean intakes of calcium were below two-thirds of the recommended level, by age group, for children in both villages. Mean intakes of riboflavin and vitamin A were below two-thirds of the recommended levels for Aloguincho children. / There were no significant differences in mean nutrient intakes with respect to age or sex of the children in either village. Nutrient intakes were significantly different, however, between the two villages. Mean intakes of energy, protein, calcium, riboflavin, niacin, vitamin C, and vitamin A were significantly lower for the Aloguincho children (those receiving the supplement) than for the La Merced children. / Although a comparison of the nutritional status of the recipients of the food supplement with the non-recipients showed no significant nutritional benefit of the supplementation program, this was probably due to insufficient intake of the supplement by the recipients, because it was also being consumed by other household members. However, the supplement is appropriate to meet the identified nutrient needs of the children. Efforts should be made to encourage increased consumption of the supplement by the recipients. / Source: Dissertation Abstracts International, Volume: 42-06, Section: B, page: 2311. / Thesis (Ph.D.)--The Florida State University, 1981.
18

SOCIO-PSYCHOLOGICAL FACTORS AFFECTING THE DIETARY INTAKE OF NON-INSTITUTIONALIZED RURAL ELDERLY

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 41-01, Section: B, page: 0135. / Thesis (Ph.D.)--The Florida State University, 1979.
19

The effectiveness of a nutrition education program designed for sodium reduction in an elderly population

Unknown Date (has links)
The effectiveness of an eight-week nutrition education program on sodium and health in 41 elderly subjects was investigated. A four-group experimental design was used consisting of the following groups: hypertensive treatment (HT); hypertensive control (HC); normotensive treatment (NT); normotensive control (NC). Effectiveness of the program was determined by changes in knowledge, changes in urinary sodium and dietary sodium, potassium and calcium intake, and taste preference for NaCl. / The program was effective in increasing knowledge with the HT and NT having a significant gain in pre- to posttest scores, (p $\leq$ 0.01 and p $\leq$ 0.05, respectively). A post-posttest, given six weeks after the nutrition classes, showed that HT retained more knowledge than NT, (15% and 6%, respectively). The only significant dietary change was an increase in dietary calcium in HT (p $\leq$ 0.05). Urinary sodium, dietary sodium and potassium decreased in the HT, levels of sodium and potassium increased slightly in the NT group. Nutrition education on sodium restriction did not affect taste preference for NaCl. A weak correlation (p = 0.057) was noted between sodium intake and taste preference for NaCl. Elderly Title III meal participants consumed more sodium, slightly more calcium and less potassium than nonparticipants. / The education program was more effective in the HT group than the NT. This result indicated that elderly with a medical need for dietary modification, such as hypertension, are more likely than elderly without a medical need to change dietary habits and increase knowledge from a nutrition education program. / Source: Dissertation Abstracts International, Volume: 51-09, Section: B, page: 4282. / Major Professor: Nancy Green. / Thesis (Ph.D.)--The Florida State University, 1990.
20

THE EFFECTS OF LONG-TERM USAGE OF ORAL CONTRACEPTIVE STEROID DRUGS ON VITAMIN-A, BETA-CAROTENE, ASCORBIC ACID, RIBOFLAVIN AND NIACIN IN WOMEN

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 35-02, Section: B, page: 0915. / Thesis (Ph.D.)--The Florida State University, 1974.

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