Spelling suggestions: "subject:"bealth ciences -- hutrition"" "subject:"bealth ciences -- elutrition""
541 |
Immunological modulation of antioxidants in side-stream cigarette smoke (SSCS) exposed miceZhang, Jin January 2002 (has links)
Environmental tobacco smoke (ETS) is a complex mixture of chemicals generated during the burning of tobacco products. The principle contributor to ETS is side-stream cigarette smoke (SSCS), the material emitted from the smoldering tobacco product between puffs Our hypothesis is that reactive oxygen species from SSCS are playing an essential role in disease promotion and antioxidant supplementation (a single form of alpha-tocopherol or a mixture of multiple antioxidants) will potentially prevent SSCS associated tissue damage, pulmonary dysfunction. The specific aims of the present study are to determine if: (1) SSCS would induce tissue lipid peroxidation and proinflammatory responses; (2) SSCS would provoke pulmonary and cardiac function changes; (3) SSCS would cause oxidative stress, reduce nutrient concentrations and suppress immune function in murine retrovirus infections; (4) dietary alpha-tocopherol, specifically, can enhance resistance to oxidative damage by SSCS and improve lung function; (5) multiple antioxidant supplementation can modulate proinflammatory cytokine secretion and tissue lipid peroxidation induced by SSCS exposure in old healthy mice. SSCS exposure methodology in a murine model was developed to facilitate these goals. For the first time we established a SSCS model in murine retrovirus infection. Also we conduced a SSCS dose-response model for a cardiac function study. We found that SSCS exposure in mice consistently increased oxidation, depleted tissue vitamin E levels, and promoted inflammatory cytokines production. SSCS exposure at 120-min/day, 5 days/week for 12 weeks decreased heart contractile function and increased vascular resistance. SSCS induced increased oxidative stress, reduced nutrient concentrations and suppressed immune function, which could make mice with murine retrovirus more susceptible to opportunistic infections. Dietary alpha-tocopherol enhanced resistance against SSCS-induced oxidation and improved lung function, primarily through the antioxidant property of alpha-tocopherol and its modulation of local cytokine production. The multiple antioxidant with beta-carotene, bioflavanoids, Coenzyme Q10, d-alpha-tocopherol, L-ascorbic acid, L-carnitine, magnesium, N-acetylcysteine, retinol, selenium and zinc given as a dietary supplementation prevented oxidation and IL-6 production in healthy old mice during SSCS exposure. (Abstract shortened by UMI.)
|
542 |
Confronting neoliberalism: Food security and nutrition among indigenous coffee-growers in Oaxaca, MexicoSesia, Paola Maria January 2002 (has links)
This dissertation analyzes the social history and current struggles of Analco and Santa Cecilia, two Chinantec peasant localities of Oaxaca, Mexico, which experienced the boom and bust years of coffee agriculture subject to the vagaries of the global market for this cash crop. It examines the last twenty-five years of State interventions toward the Indian peasantry, focusing especially on current neoliberal economic and social policies, to reveal how they have affected local well-being and livelihood strategies. In the course of describing food security and nutrition, I show how Analqueno and Cecilieno men, women and children have coped with major changes in Mexican politics and the economy; changes toward which they have devised multiple responses, but upon which they have had limited control. In particular, I explore how members of these communities weighed options and maximized opportunities in their attempt to maintain, restore or enhance food security and local well-being during the coffee crisis of the 1990s. I show how, in the last decade, agricultural diversification for both home consumption and the market, and a partial retreat from commercial agriculture centered around coffee have become significant. Finally, I consider the nutritional effects of the coffee boom and bust years on the local populations paying particular attention to children, teenagers, and gender differences.
|
543 |
The effect of a high fruit and vegetable, low fat dietary intervention on immune function, DNA adduct formation, and body composition among breast cancer survivorsThomson, Cynthia, 1957- January 1998 (has links)
Each year in the United States five percent of the over 2.5 million women living with breast cancer will have a recurrence. The possibility that dietary change may increase breast cancer-free survival is currently under investigation. Three mechanisms by which diet may have an effect include: (1) improved immunity, (2) reduced oxidative DNA damage and (3) reduced body weight and fat. The hypothesis of this dietary intervention study was that women previously treated for breast cancer who adhere to a diet high in fruit, vegetables and fiber and low in fat would demonstrate improved immune function, reduced oxidative DNA damage and reduced body weight and fat as compared to women assigned to the control diet. Seventy-seven women treated for Stage I, II or IIIA breast cancer were enrolled in this clinical trial. Sixty-six completed the six month intervention. The average participant was caucasian, educated, postmenopausal and 52 years of age. At the end of six months the intervention the diet group showed significantly higher natural killer cell (NKC) lysis at an effector to target cell (E:T) ratio of 100:1. Lytic units were not significantly different. Diet was not associated with immune function except for beta-carotene intake which was associated with greater changes in the percentage of NKCs in the intervention group. Oxidative DNA damage was significantly lower among participants in the intervention diet group at the end of the study. Oxidative DNA damage was inversely associated with intake of vegetables, fruit and micronutrients thereof and positively associated with dietary fat, saturated fat and meat intake. No significant differences in body weight or fat were identified; however, both groups showed a significant decrease in body fat of 1.0%. In conclusion, the dietary intervention was able to produce significant changes in nutrient intake, a significant increase in NKC activity at an E:T ratio of 100:1 but not other immune markers, and significant reductions in oxidative DNA damage among breast cancer survivors. The role of NKC immunity and reduced DNA damage in relationship to breast cancer recurrence remains to be determined. A longer term, larger study should provide the answer.
|
544 |
Role of dietary supplement (Pycnogenol (RTM)) in health promotionHosseini, Saeed January 2000 (has links)
Increasing evidence implicates the role of reactive oxygen species in the pathogenesis of several diseases such as cardiovascular disease. Recent studies also suggest a role for reactive oxygen species in the control of vascular smooth muscle proliferation both in vitro and in vivo. By altering the balance in the endothelium between vasoconstrictors such as thromboxane, isoprostanes and vasodilators such as nitric oxide, reactive oxygen species contribute to endothelium-dependent contractions and increased vascular resistance. Studies in animal models of atherosclerosis suggest that natural and synthetic antioxidants can retard the development of atheroma. Antioxidants can restore endothelial function and decrease blood pressure in several models of hypertension and in some essential hypertension of humans. Epidemiological comparisons between populations and studies within populations also support the contention that high plasma levels or dietary intake of natural antioxidant may protect against the development of coronary disease in man. Endothelial dysfunction is increasingly recognized as an early event in the pathogenesis of cardiovascular disease. Endothelial dysfunction and coronary artery diseases are both linked to hypertension. Modification of these conditions improves both endothelial function and coronary artery disease outcomes. Dietary and lifestyle modifications and antioxidant vitamin supplementation have a beneficial effect on endothelial function, as do angiotensin-converting enzyme inhibitors and lipid-lowering agents. Oxidative stress increases cell proliferation, mediates hormone-induced hypertrophy, and under some circumstances-induces apoptosis. Smooth muscle cells contain a reduced nicotinamide adenine dinucleotide/reduced nicotinamide adenine dinucleotide phosphate oxidase that is responsible for the majority of the superoxide produced by the vessel wall. This enzyme has been characterized biochemically, but only limited information is available regarding its molecular structure. High levels of oxidative stress are apparently involved in the pathogenesis of vascular diseases such as hypertension and atherosclerosis. Thus the pathways responsible for oxidative stress, as well as the antioxidant defenses in the vessel wall, may provide novel therapeutic targets.
|
545 |
Canthaxanthin and tumor growth in miceHuang, Dennis Shihchang, 1957- January 1990 (has links)
Canthaxanthin (CX), a non-provitamin A carotenoid, has been shown to exert a variety of effects on cells of the immune system and to have tumor-specific cytopathic effects in vivo and in vitro. In the present study, CX was shown to inhibit the in vitro growth of three murine tumor cell lines, JB/MS melanoma, B16F10 melanoma, and PYB6 fibrosarcoma. This effect was dose-dependent up to a concentration of CX of 10⁻⁴M. In contrast, the growth of NIH-3T3 fibroblasts was enhanced following a 96 hr incubation with 10⁻⁴M CX. A dietary supplement of 1% CX retarded tumor growth in LP-BM5 retrovirus-infected female C57BL/6 mice after tumor challenge, but had no effect on tumor growth in normal, uninfected animals. Although, NK activity and T and B subpopulations were not modified by dietary CX after tumor challenge, irrespective of whether mice had been virus-infected, there was a slight enhancement of mitogen-stimulated IFN-τ production by virus-infected murine spleen cells when compared with non-infected cells. We suggest that CX has potential as a modifier of cancer cell growth, especially in situation where impairment of the immune system has occurred as a result of viral infection.
|
546 |
The relationship between body-mass index and academic achievement in third-grade white femalesSteiniger, Laura, 1950- January 1997 (has links)
This study examined the relationship between BMI and academic achievement in third-grade white females. Academic achievement was determined by classroom grades and standardized achievement test scores (e.g. CTBS). Also assessed were teachers' predictions for school success and teachers' perception of student behavior. The results of the investigation indicated no statistically significant differences in classroom grades between groups of "normal-weight" students and a group of obese students. However, teachers predicted less school success for obese girls and the highest degree of school success for the thinnest girls, and ANCOVA revealed statistically significant lower CTBS scores for obese girls. While MANCOVA of BMI and other confounding factors on CTBS scores showed BMI was not statistically significant, a relationship does exist. A model is proposed linking BMI and academic achievement through the mediating factors of teachers' predictions for success (teacher expectancies) and parents' level of education.
|
547 |
Vitamine K et fonctions cognitives chez la personne âgée en santé : une approche épidémiologique nutritionnellePresse, Nancy 07 1900 (has links)
La vitamine K fait l’objet d’un intérêt croissant en regard du rôle qu’elle peut jouer dans la santé humaine hormis celui bien établi dans la coagulation sanguine. De plus en plus d’études expérimentales lui confèrent des fonctions dans le système nerveux central, particulièrement dans la synthèse des sphingolipides, l’activation de la protéine vitamine K-dépendante Gas6 et la protection contre les dommages oxydatifs. Toutefois, il demeure beaucoup moins bien établi si la perturbation de ces fonctions peut conduire à des déficits cognitifs. L’objectif principal de cette thèse est de vérifier l’hypothèse selon laquelle le statut vitaminique K des personnes âgées en santé est un déterminant de la performance cognitive. En vue de la réalisation de cet objectif, une meilleure compréhension des indicateurs du statut vitaminique K s’avérait nécessaire. Chacune des études présentées vise donc un objectif spécifique : 1) évaluer le nombre de rappels alimentaires de 24 heures non consécutifs nécessaire pour mesurer l’apport habituel de vitamine K des personnes âgées; 2) évaluer la valeur d’une seule mesure de la concentration sérique de vitamine K comme marqueur de l’exposition à long terme; et 3) examiner l’association entre le statut vitaminique K et la performance cognitive des personnes âgées en santé de la cohorte québécoise NuAge. Trois dimensions cognitives ont été évaluées soient la mémoire épisodique verbale et non-verbale, les fonctions exécutives et la vitesse de traitement de l’information.
Cette thèse présente la première étude appuyant l’hypothèse d’un rôle de la vitamine K dans la cognition chez les personnes âgées. Spécifiquement, la concentration sérique de vitamine K a été associée positivement à la performance en mémoire épisodique verbale, et plus particulièrement au processus de consolidation de la trace mnésique. En accord avec les travaux chez l’animal et l’action de la protéine Gas6 dans l’hippocampe, un rôle spécifique de la vitamine K à l’étape de consolidation est biologiquement plausible. Aucune association significative n’a été observée avec les fonctions exécutives et la vitesse de traitement de l’information. Parallèlement, il a été démontré qu’une mesure unique de la concentration sérique de vitamine K constitue une mesure adéquate de l’exposition à long terme à la vitamine K. De même, il a été établi que six à 13 rappels alimentaires de 24 heures sont nécessaires pour estimer précisément l’apport de vitamine K des personnes âgées en santé. Collectivement, les résultats de ces deux études fournissent des informations précieuses aux chercheurs permettant une meilleure interprétation des études existantes et une meilleure planification des études futures. Les résultats de cette thèse constituent une avancée importante dans la compréhension du rôle potentiel de la vitamine K dans le système nerveux central et renforce la nécessité qu’elle soit considérée en tant que facteur nutritionnel du vieillissement cognitif, en particulier chez les personnes traitées par un antagoniste de la vitamine K. / There is an increasing interest in the potential roles of vitamin K in human health aside from the one well established in blood clotting. Notably, a growing number of experimental studies show that vitamin K has biological functions in the central nervous system, particularly in the synthesis of sphingolipids, the activation of the vitamin K-dependent protein Gas6, and the prevention of oxidative damage. However, it remains uncertain whether the disruption of these functions can lead to cognitive deficits. The main objective of this thesis is to test the hypothesis that vitamin K status is a determinant of cognitive performance in healthy older adults. In order to achieve this goal, a better understanding of vitamin K status indicators was needed. Accordingly, three studies are presented each aiming at a specific objective: 1) estimate the number of non-consecutive 24-hour dietary recalls needed to assess usual vitamin K intake; 2) determine whether a single measurement of serum vitamin K concentration is an adequate indicator of long-term vitamin K exposure; and 3) examine the association between vitamin K status and cognitive performance in healthy older adults from the Québec NuAge Study. Three cognitive domains were assessed namely verbal and non-verbal episodic memory, executive functions, and speed of processing.
This thesis presents the first study providing support for a role of vitamin K in cognition in older adults. Specifically, serum vitamin K concentration was positively associated with performance in verbal episodic memory, particularly in the consolidation process of the memory trace. Consistent with rodent studies and the action of the protein Gas6 in the hippocampus, a specific role of vitamin K in memory consolidation is biologically plausible. No significant association was observed with executive functions and speed of processing. Additionally, it was established that a single measurement of serum vitamin K concentration is adequate for assessing long-term vitamin K exposure in healthy older adults. Similarly, it was determined that six to 13 24-hour dietary recalls are needed to accurately assess usual vitamin K intake. Collectively, both studies provide valuable information to researchers for better interpretation of existing studies and planning future ones. Results from this thesis constitute an important step in the understanding of the potential role of vitamin K in the central nervous system, emphasizing the need to consider this micronutrient as a nutritional factor of cognitive aging, especially among those treated with vitamin K antagonists.
|
548 |
A study of childhood eating habits in the United States and their association with race and genderAdams, Samuel 09 August 2013 (has links)
<p> The purpose of the study was to obtain a better understanding of childhood eating habits and their association with race and gender. With this understanding, a sustainable intervention program that includes proper nutrition will help resolve the obesity issue that is affecting families throughout the nation. </p><p> The study collected the nutritional data on a total of 8,945 children that were surveyed by California Health Interview Survey (CHIS). The children varied in race, sex, family income, and education. The age range was 6 to 12.</p><p> The sources analyzed indicate that childhood obesity is increasing in alarming numbers throughout the United States. And that it can be directly attributed to nutrition and lack of physical exercise.</p>
|
549 |
The affect of acculturation on obesity among foreign-born Asians residing in the United StatesSmith, Charlotte 09 August 2013 (has links)
<p> This study examined the relationship between acculturation and obesity in foreign-born Asians residing in the United States. Two proxies were used to measure level of acculturation: years of United States residency and English language use and proficiency. Hypothesis 1 predicted that acculturation measured as number of years of residence will positively predict obesity. Hypothesis 2 predicted that acculturation measured as English language preference and proficiency will positively predict obesity.</p><p> The study used data from the 2009 California Health Interview Survey. Study participants met two inclusion criteria: foreign born and Asian. Point Biserial was run to determine whether or not there was a correlation.</p><p> Results showed a weak relationship between obesity and both variable used to measure acculturation. Additional exploratory analysis was performed to determine whether or not there was a relationship between obesity and acculturation for each Asian ethnicity. Results of this exploratory analysis were mixed. </p>
|
550 |
Knowledge and awareness of the Female Athlete Triad among female collegiate athletes at California State University, Long BeachTabone, Brenda 09 August 2013 (has links)
<p> The Female Athlete Triad is a syndrome defined by disordered eating, amenorrhea, and osteoporosis seen in female athletes. This directed project presented the assessment of knowledge and the importance of education among female athletes regarding the Female Athlete Triad. The researcher worked with the athletic department and the female athletes at California State University, Long Beach. A quantitative study, quasi-experimental, one-group design was completed. A one-group pretest- posttest was used on 45 female athletes to evaluate their knowledge base before and after the educational intervention. </p><p> Results indicated a significant increase in the athletes' scores for knowledge of the Female Athlete Triad between the pretest and posttest (<i> p</i> < .01). The increase in scores signified that a 1-hour education session improved the knowledge base for the female athletes of the Female Athlete Triad. A major recommendation would be to include coaches, trainers, and parents in the educational process.</p>
|
Page generated in 0.0778 seconds