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1
Fradera, Ursula G. "Impact of vitamin A nutrified soybean oil on the vitamin A status of a selected community in Southern Brazil." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28986.
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Previous studies have revealed that marginal vitamin A deficiency poses a common public health problem among poor population groups in Southern Brazil. Nutrification programs in Guatemala (sugar) and in the Philippines (MSG) have resulted in improved vitamin A status, accompanied by positive changes in the anthropometric and general health status. Accordingly, the main purpose of the present pilot study was to evaluate the potential impact of vitamin A nutrified soybean oil on the vitamin A status of a selected community in Southern Brazil. Additional objectives were to assess the vitamin A and general nutritional status of the participants.
The study was conducted in Vila Piratininga, a shanty town located on the periphery of Ribeirao Preto, a typical agricultural town in the sugarcane and coffee region of the state of Sao Paulo. Fifty-seven families were randomly assigned to experimental and control groups and were provided for four months with soybean oil that was either fortified with vitamin A (92,000 IU of retinyl palmitate per one litre can) or unfortified.
To evaluate the impact of nutrification, biochemical and dietary indicators of vitamin A status were assessed before and after the supplementation. Dietary intake data were obtained from the female head of each household using the 24 hour recall method. Additional information on the usual consumption pattern of vitamin A containing foods was collected at the start of the study, using a food frequency questionnaire. Plasma retinol and (β-carotene levels of all subjects were analysed. Anthropometric measurements served as additional indicator of general nutritional status. Furthermore, throughout the intervention mothers, were questioned about the incidence of diarrhea and respiratory diseases among their children.
Results from the serum vitamin A analysis at baseline confirmed that vitamin A deficiency was a public health problem among this low income population. Forty percent (control group) and
59% (experimental group) of preschool children, the most vulnerable age group, had low or deficient serum retinol concentrations. Plasma (β -carotene and dietary data showed that the intake of vitamin A and carotenoids from the rice and bean based diet was very low. The consumption of nutrified soybean oil increased the estimated daily vitamin A intake of the experimental group by 500% (p<0.001). However, this improved intake was not reflected in plasma retinol levels. Plasma vitamin A values of supplemented individuals dropped significantly (p<0.001) during the intervention, indicating that vitamin A nutrified soybean oil was not effective in improving their vitamin A status.
The lack of response to supplementation in this study does not necessarily suggest that soybean oil is not a feasible vehicle for vitamin A nutrification. The fortified oil was well accepted by the participants and used daily for the preparation of meals; eventual losses of vitamin A during cooking and/or storage can be regarded as minimal. Therefore, this negative impact is more likely due to other factors. In populations with marginal vitamin A deficiency, as in Vila. Piratininga, the limitations of serum retinol levels as an accurate indicator of vitamin A body reserves should be appreciated. In addition, morbidity data revealed that infections were common among participating children. Infections may have impaired vitamin A absorption and utilization, increased requirements and consequently interfered with a successful nutrification.
This was the first study to use vegetable oil as the carrier for vitamin A. Although this trial did not result in the expected impact on vitamin A status of the present study population, the feasibility of this vehicle should be further studied. In future investigations, the relative dose response test (RDR), which is a more sensitive index of vitamin A body reserves, should be performed on a subsample of the whole study population. Furthermore, concurrent reduction in the magnitude and severity of precipitating or contributary risk factors such as parasitic infestation, diarrheal and respiratory infections could improve the outcome of a nutrification intervention.Land and Food Systems, Faculty of
Graduate
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Nelson, Monica. "Serum 25-Hydroxyvitamin D Response to Daily Oral Supplementation with 800 IU Cholecalciferol in Premenopausal Women Living in Maine." Fogler Library, University of Maine, 2007. http://www.library.umaine.edu/theses/pdf/NelsonM2007.pdf.
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Wolberg, Charlene. "The influence of vitamin D3 supplementation on the components of the metabolic syndrome." Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/80088.
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Thesis (MNutr)--Stellenbosch University, 2013.ENGLISH ABSTRACT: The possible advantages of vitamin D supplementation on various cardiometabolic conditions have been examined over the past few years. Vitamin D supplementation has possibly shown effects on each of the individual components of the metabolic syndrome i.e.: obesity, hypertension, dyslipidaemia and glucose intolerance. The aim of this systematic review was to ascertain whether or not vitamin D supplementation has any effect on any of the components of the metabolic syndrome. We searched the (Cochrane Central Register of Controlled Trails (Central), Medline, Science direct, ISI Web of knowledge and Scopus during 2010 (repeated search in 2012). We found four randomized controlled trials that met our inclusion and exclusion criteria. Three hundred and seventy three patients were included in these four randomized controlled trails comparing vitamin D supplementation with placebo. Duration of treatment was a minimum of 4 weeks, through to a maximum of on-year. The different trials looked at various components of the metabolic syndrome as outcomes. The results were not consistent amongst the trials and the results could not be combined in a meta-analysis due to heterogeneity in study design and outcomes measured. The current systematic review highlights the shortcomings in the published data and we recommend further trials be undertaken before vitamin D supplementation can be recommended as beneficial for patients with the metabolic syndrome.
AFRIKAANSE OPSOMMING: Die moontlike voordele van vitamien D-aanvullings op verskillende kardiometaboliese toestande is oor die afgelope paar jaar ondersoek. Daar is aangetoon dat vitamien Daanvullings uitwerkings het op elk van die individuele komponente van die metaboliese sindroom naamlik vetsug, hipertensie, dislipidemie en glukose-intoleransie. Die doel van hierdie sistematiese oorsig was om vas te stel of vitamien D-aanvullings enige uitwerking het op enige van die komponente van die metaboliese sindroom of nie. Ons het gedurende 2010 soektogte uitgevoer op die Cochrane Sentrale register van gekontroleerde proewe (Central), Medline, Science Direct, ISI Web of Knowledge en Scopus (soektog is in 2012 herhaal). Ons het vier verewekansigde gekontroleerde proewe wat aan ons insluiting- en uitsluitingskriteria voldoen het, opgespoor. Driehonderd drie en sewentig pasiënte is by die vier proewe ingesluit. Al vier proewe het vitamien D-aanvullings met plasebo vergelyk. Die duur van behandeling het van 4 weke tot een jaar gestrek. Die verskillende proewe het gekyk na verskillende komponente van die metaboliese sindroom as uitkomste. Die resultate van die onderskeie proewe was nie konsekwent nie. Die huidige sistematiese oorsig belig die tekortkominge in die gepubliseerde data en ons beveel aan dat verdere proewe onderneem word om vas te stel of dit nuttig is om vitamien D aanvullings vir pasiënte met die metaboliese sindroom aan te beveel, en of dit dalk skadelik kan wees.
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Simoneau, Nathalie. "Attributes of vitamin A and calcium-rich foods consumed in K'asho Got'ine, NWT." Thesis, McGill University, 1997. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27412.
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Over 60% of the population in K'asho Got'ine, NWT, obtained less than 2/3 of the Recommended Nutrient Intakes (RNI) for vitamin A and calcium, as reported in a previous nutritional assessment. Focus group discussions and a food preference assessment were conducted with adults in order to identify the cultural, ecological, and socioeconomic factors (food attributes) as well as the individual preferences which influence the consumption of vitamin A and calcium-rich traditional and market foods in K'asho Got'ine. The major attributes limiting intakes of traditional food rich in vitamin A and calcium included: lack of equipment for hunting/fishing; seasonality; distance traveled to obtain certain foods; occasional unhealthy appearance of food; no hunter/fisher in the household. The major food attributes reported as barriers to greater intakes of selected market foods were: cost, freshness, intolerance to certain items, availability and unfamiliarity. Foods that received the highest preference scores were rabbit liver, loche liver, and Canada goose meat (smoked/dried) for vitamin A-rich foods and connie eggs, rabbit flesh, woodland and barrenland caribou head for calcium-rich foods. Criteria for selection of traditional and market foods to promote in the community included: (1) convenience of the food; (2) difficulty to overcome barriers to increasing food consumption; (3) concentration level of contaminants in certain traditional food; and (4) food preference score. This study identified available and underutilized traditional and market foods rich in vitamin A and calcium which are most acceptable to the community, and may be promoted in future nutrition intervention programs.
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Wilkins, Jennie P. "Relationship between maternal prenatal vitamin use and infant iron status." Morgantown, W. Va. : [West Virginia University Libraries], 2002. http://etd.wvu.edu/templates/showETD.cfm?recnum=2381.
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Thesis (M.S.)--West Virginia University, 2002.Title from document title page. Document formatted into pages; contains vi, 43 p. Vita. Includes abstract. Includes bibliographical references (p. 34-36).
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Clarke, Michael William. "Vitamin E metabolism in humans." University of Western Australia. School of Medicine and Pharmacology, 2008. http://theses.library.uwa.edu.au/adt-WU2008.0191.
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[Truncated abstract] Vitamin E is comprised of a family of tocopherols (TOH) and tocotrienols. The most studied of these is [alpha]-tocopherol ([alpha]-TOH), as this form is retained within the body and any deficiency of vitamin E is corrected with this supplement. [alpha]-TOH is a lipid-soluble antioxidant required for the preservation of cell membranes and potentially acts as a defense against oxidative stress. Individuals who have a primary vitamin E deficiency such as low birth weight infants, secondary vitamin E deficiency due to fat malabsorption such as in abetalipoproteinaemia, or a genetic defect in TOH transport require supplementation. There is debate as to whether vitamin E supplementation in other patient groups is required. Vitamin E supplementation has been recommended for persons with FHBL, a rare disorder of lipoprotein metabolism that leads to low serum [alpha]-TOH and decreased LDL cholesterol and apolipoprotein B concentrations. We examined the effect of truncated apoB variants on vitamin E metabolism and oxidative stress in persons with heterozygous FHBL. We used HPLC with electrochemical detection to measure [alpha]- and [gamma]-TOH in serum, erythrocytes, and platelets, and GC-MS to measure urinary F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. Erythrocyte [alpha]-TOH was decreased, but we observed no differences in lipid-adjusted serum TOHs, erythrocyte [gamma]-TOH, platelet [alpha]- or [gamma]-TOH, urinary F2-isoprostanes, or TOH metabolites. Taken together, our findings do not support the recommendation that persons with heterozygous FHBL should receive vitamin E supplementation. ... Sesame lignans are natural components of sesame seed oil and there is evidence that these lignans can inhibit CYP450 enzymes, in particular, those responsible for vitamin E metabolism. We hypothesised that sesame seed ingestion would increase serum [gamma]-TOH, lower plasma lipids and inhibit platelet function in human subjects with at least one cardiovascular risk factor. We used HPLC with electrochemical detection to measure [alpha]- and -TOH in serum and GC-MS to measure F2-isoprostanes and TOH metabolites as markers of oxidative stress and TOH intake, respectively. We used high-sensitive C-reactive protein as a measure of systemic inflammation. Platelet function was assessed using the PFA-100 platelet aggregation assay. Although serum [gamma]-TOH increased by 17%, we observed no effect on lipid metabolism, markers of inflammation, oxidative stress or platelet function following treatment with ~25 g/day sesame seeds for five weeks. Our findings challenge the hypothesis that sesame seed ingestion provides beneficial cardiovascular effects. In summary, we have studied the metabolism and transport of both [alpha]- and [gamma]-TOH in humans to evaluate the requirements for supplementation and the effects of vitamin E on platelet function and CYP3A4 activity. Specialised techniques using HPLC were developed to measure serum and cellular TOH concentrations both in supplemented and un-supplemented individuals. We also used GCMS to provide a sensitive, accurate assessment of TOH metabolites and midazolam pharmacokinetics in humans after vitamin E supplementation. We have examined the role vitamin E has on important biochemical endpoints, with emphasis on the implications for TOH supplementation in subjects at risk of CVD.
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Chaomuangbon, Sunthorn. "The Response of Elderly People to a B-6 Supplement." Thesis, North Texas State University, 1985. https://digital.library.unt.edu/ark:/67531/metadc500731/.
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Vitamin B-6 status was examined in a group of 46 elderly subjects who were selected from nursing home residents, hospital patients, and free living individuals in Denton County. Subjects were limited to men and women over 60 years of age. Erythrocyte aspartate aminotransferase stimulation with pyridoxal phosphate (in-vitro) was studied as the biochemical criterion of vitamin B-6 status. The pyridoxine status of these 46 subjects (the reference group) was measured in order to be able to identify people with a relatively poor B-6 status. A sub-group of the reference group was composed of 4 subjects who took B-6 supplements (supplemented group). There was no significant difference (0.05 level) in the basal activity, stimulated activity, percentage stimulation, or body weight, after treatment with 10 mg pyridoxine hydrochloride for 4 weeks, even though all 4 subjects had an improved B-6 status (based on percentage stimulation) after taking the supplement. The data indicated that of the 4 subjects tested, 2 showed a large change in the basal activity, stimulated activity, and percentage stimulation. The lack of significant difference (0.05 level) was probably due to a small sample size. One subject reported an increased appetite and body weight after treatment with pyridoxine.
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Nihan, Laura. "Conjunctival Impression Cytology Assessment of Vitamin A Status of Migrant Children." DigitalCommons@USU, 1995. https://digitalcommons.usu.edu/etd/5437.
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Subclinical vitamin A deficiency was assessed in 65 Hispanic children attending four migrant Head Start programs in Utah. Subjects aged 2 to 6 years (median 3 years 10 months) were examined for evidence of vitamin A deficiency by conjunctival impression cytology. Biochemical indices for serum vitamin A, retinol-binding protein, zinc, and iron were performed.
Of eight children (12.5%) with subclinical vitamin A deficiency, one child had a marginal serum vitamin A of 11 μg/dl. Retinol-binding protein concentrations were significantly lower in two subjects with abnormal conjunctival impression cytology. Serum zinc, which when low can mimic signs of ocular vitamin A lesions, was normal for all 65 subjects. Fifteen children (23%) had iron-deficiency anemia.
Logistic regression was the central method of analysis used in this study. The results of the statistical analyses indicated there was a correlation value (0.31) between abnormal conjunctival impression cytology and serum vitamin A, which supports the hypothesis that abnormal conjunctiva! impression cytology is concurrent with decreased serum vitamin A.
Assessment of vitamin A status of Hispanic migrant children by impression cytology was effective in identifying children at risk for hypovitaminosis A. Beyond vitamin A's role in vision and maintenance of epithelium, it is also required for growth and hematopoiesis. The children of migrant workers may be suffering physiologically important consequences of vitamin A and iron deficiency that can be prevented by screening with biochemical and histological testing. Nutrition intervention for deficient children is warranted.
9
Favret, Jenny C. "An incidence study of vitamin and mineral supplementation among infants in Southwest Virginia." Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/101275.
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A longitudinal feeding study of 154 infants in Southwest Virginia was conducted during 1978-1980. The incidence of vitamin and mineral supplementation among these infants was the focus of the retrospective study discussed here.
With the use of the Nutritional Analysis System of Louisiana State University, nutrient adequacy levels were determined. Vitamin D, vitamin E, folacin, vitamin B-6, and iron were the problem nutrients identified through this analysis. Inappropriate infant feeding practices such as the use of low iron formulas, the use of cow's milk, and the consumption of inadequate milk volume were blamed for these dietary deficiencies.
Routine vitamin supplementation was common among infants of all feeding types. While much of the supplementation was unnecessary, large percentages of infants demonstrated a need for it. The exception was vitamin A. None of the infants who received supplemental vitamin A had inadequate dietary intakes of this nutrient. Supplementation was not shown to have an effect on weight or length gain measurements.
Parents should be given specific infant feeding instructions prior to hospital discharge. Included should be a list of the circumstances which would indicate the need for supplementation.M.S.
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Tshihwanambi, T. P. "Consumption patterns of vitamin a-rich foods of 10-13 year old children living in a rural area in Venda." Pretoria : [s.n.], 2008. http://upetd.up.ac.za/thesis/available/etd-06132008-154920.
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Bruno, Richard S. "The role of oxidative stress and vitamin C on vitamin E utilization in humans." Connect to this title online, 2004. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1085146668.
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Thesis (Ph. D.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xiv,148 pages; also includes graphics Includes bibliographical references (p. 121-136). Available online via OhioLINK's ETD Center
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Powell, Lisa. "Effects of various diets on vitamin B-6 and cholesterol levels in ten men aged 21-37." Virtual Press, 1990. http://liblink.bsu.edu/uhtbin/catkey/722433.
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Vitamin B-6 is a vitamin often promoted by the popular press as a cure all. It's role is also being studied in regard to pre-menstrual syndrome, myocardial infarction and alterations in lipid and fatty acid metabolism. This study was designed to investigate whether there was a difference between vitamin B-6 blood levels, during a baseline study, a period of vitamin B-6 depletion and vitamin B-6 supplemention in ten men ages 21-37. The effect of each diet on total cholesterol was also investigated.The experimentally accessible population for this study Laboratory as part of a larger study conducted by Dr. Stephen Coburn of the Fort Wayne State Developmental Center.Analysis of the data indicated:1) A significant difference between red blood cell pyridoxal phosphate and blood plasma levels of vitamin B-6 during the baseline, depletion and supplementation phases in ten men 21-37.2) Total serum cholesterol levels fell significantly through all phases of the study. High density lipoproteins fell significantly during the depletion phase but did not rise significantly during the supplementation phase. Low density lipoproteins showed no significant difference during the three phases of the study. When dietary records were evaluated mean dietary intake during the baseline and supplementation phases of the diet met the Recommended Dietary Allowance (RDA) for vitamin B-6. Mean protein intake also met the RDA with 102.1 grams during the baseline phase and 106.1 grams during the supplementation phase. These intakes are consistent with those found in previous studies conducted by the USDA. Mean intake of fat was lower than the 30 percent of calories recommended by the American Heart Association but wide variation existed among subjects.No physical symptoms of vitamin B-6 deficiency manifested themselves during the study. Subjects reported no other problems associated with low vitamin B-6 intakes.The data indicated that vitamin B-6 intake effects the amount of red blood cell plasma pyridoxal phosphate and plasma vitamin B-6. No clear effect can be found between vitamin B-6 intake and serum cholesterol levels. "Normal" diets also appeared to provide adequate vitamin B-6 to meet both RDA's and somatic needs. Wide variation seems to exist, however, among individuals.Department of Home Economics
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Santos, Vanessa Lorenço Peresi dos [UNESP]. "Associação entre os polimorfismos do gene BCMO1 (β-caroteno 15,15'-monooxigenase 1) e as concentrações séricas de β-caroteno e retinol em diferentes etnias brasileiras." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/132849.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A vitamina A tem importância na nutrição humana, uma vez que a sua deficiência é considerada um sério problema de saúde pública e de morbimortalidade infantil. Carotenóides pró-vitamina A, particularmente o β-caroteno proveniente de determinados alimentos de origem vegetal, são importantes fontes de vitamina A para muitas populações. Durante o processo de bioconversão os carotenóides são clivados pela enzima citossólica β-caroteno 15,15'-monooxigenase 1 (BCMO1). Dois polimorfismos (Single Nucleotide Polymorphisms - SNPs) no gene BCMO1, R267S: rs12934922 e A379V: rs7501331, foram identificados em populações de etnias Caucasiana, Japonesa e Chinesa, podendo causar redução da atividade enzimática da BCMO1 e justificar a ampla diferença inter-individual na bioconversão do β-caroteno em vitamina A. Os objetivos deste estudo foram identificar a frequência das variantes polimórficas A379V e R267S/A379V do gene BCMO1 em três grupos populacionais brasileiros (brancos, negros e japoneses) e avaliar a relação entre os SNPs com as concentrações séricas de β-caroteno e retinol entre os três diferentes grupos étnicos. Cada grupo foi composto de 100 indivíduos voluntários, com ancestralidades Europeia, Africana e Japonesa, sendo 50% do gênero feminino e 50% do gênero masculino. Foram avaliadas as concentrações séricas de β-caroteno, retinol, zinco eritrocitário, linfócitos, proteína C-reativa, α-1-glicoproteína ácida e a ingestão alimentar de Vitamina A. Amostras de saliva e esfoliado de células da mucosa oral foram coletadas para a extração de DNA com posterior genotipagem dos SNPs A379V: rs7501331 e R267S: rs12934922 por RT-PCR. As frequências das variantes alélicas R267S e A379V com, pelo menos, um alelo T para os indivíduos com ancestralidade Europeia foram 63,0% e 44,0%, respectivamente, com ancestralidade Africana, 48,0% e 18,0%, respectivamente, e com ancestralidade Japonesa, 21,0% e 27,0%,...
Vitamin A is important in human nutrition, since deficiency is considered a serious public health and child mortality. Provitamin A carotenoids, particularly β-carotene from certain plant foods are important sources of vitamin A for many populations. During the bioconversion process carotenoids are cleaved by cytosolic enzyme β-carotene 15,15'-monooxygenase 1 (BCMO1). Two polymorphisms (Single Nucleotide Polymorphisms - SNPs) in BCMO1 gene, R267S: rs12934922 and A379V: rs7501331, were identified in ethnic populations of Caucasian, Japanese and Chinese, and it may cause reduced enzyme activity BCMO1 and justify the wide inter-individual differences in bioconversion of β-carotene into vitamin A. The aims of this study were to identify the frequency of polymorphic variants A379V and R267S/A379V of BCMO1 gene in three population groups (whites, blacks and Japanese) and evaluate the relationship between SNPs with serum β-carotene and retinol among three different ethnic groups. Each group was composed of 100 volunteers, with European, African and Japanese ancestry, and 50% were female and 50% male. Were evaluated plasmatic concentrations of β-carotene, retinol, zinc erythrocyte, lymphocytes, C-reactive protein, α-1-acid glycoprotein and dietary intake of Vitamin A. Samples of saliva and oral mucosa exfoliated cells were collected for DNA extraction with subsequent genotyping of SNPs R267S: rs12934922 and A379V: rs7501331 by RT-PCR. The frequencies of allelic variants R267S and A379V at least one T allele for individuals with European ancestry were 63.0% and 44.0%, respectively, African ancestry, 48.0% and 18.0%, respectively, and Japanese ancestry, 21.0 % and 27.0%, respectively. The results show, so unique, that the frequencies of polymorphic variants of the polymorphic variants A379V and R267S BCMO1 gene in Brazilian population groups evaluated depend on ethnicity for both SNPs. The polymorphic variants observed do not seem to ...
FAPESP: 2011/07057-2
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Santos, Vanessa Lorenço Peresi dos. "Associação entre os polimorfismos do gene BCMO1 (β-caroteno 15,15'-monooxigenase 1) e as concentrações séricas de β-caroteno e retinol em diferentes etnias brasileiras /." Botucatu, 2015. http://hdl.handle.net/11449/132849.
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Orientador: Lúcia Regina RibeiroCoorientador: Daisy Maria Favero Salvadori
Banca: Marcos Ferreira Minicucci
Banca: Maria Rita Marques de Oliveira
Banca: Mário Sérgio Mantovani
Banca: Raquel Alves dos Santos
Resumo: A vitamina A tem importância na nutrição humana, uma vez que a sua deficiência é considerada um sério problema de saúde pública e de morbimortalidade infantil. Carotenóides pró-vitamina A, particularmente o β-caroteno proveniente de determinados alimentos de origem vegetal, são importantes fontes de vitamina A para muitas populações. Durante o processo de bioconversão os carotenóides são clivados pela enzima citossólica β-caroteno 15,15'-monooxigenase 1 (BCMO1). Dois polimorfismos (Single Nucleotide Polymorphisms - SNPs) no gene BCMO1, R267S: rs12934922 e A379V: rs7501331, foram identificados em populações de etnias Caucasiana, Japonesa e Chinesa, podendo causar redução da atividade enzimática da BCMO1 e justificar a ampla diferença inter-individual na bioconversão do β-caroteno em vitamina A. Os objetivos deste estudo foram identificar a frequência das variantes polimórficas A379V e R267S/A379V do gene BCMO1 em três grupos populacionais brasileiros (brancos, negros e japoneses) e avaliar a relação entre os SNPs com as concentrações séricas de β-caroteno e retinol entre os três diferentes grupos étnicos. Cada grupo foi composto de 100 indivíduos voluntários, com ancestralidades Europeia, Africana e Japonesa, sendo 50% do gênero feminino e 50% do gênero masculino. Foram avaliadas as concentrações séricas de β-caroteno, retinol, zinco eritrocitário, linfócitos, proteína C-reativa, α-1-glicoproteína ácida e a ingestão alimentar de Vitamina A. Amostras de saliva e esfoliado de células da mucosa oral foram coletadas para a extração de DNA com posterior genotipagem dos SNPs A379V: rs7501331 e R267S: rs12934922 por RT-PCR. As frequências das variantes alélicas R267S e A379V com, pelo menos, um alelo T para os indivíduos com ancestralidade Europeia foram 63,0% e 44,0%, respectivamente, com ancestralidade Africana, 48,0% e 18,0%, respectivamente, e com ancestralidade Japonesa, 21,0% e 27,0%,...
Abstract: Vitamin A is important in human nutrition, since deficiency is considered a serious public health and child mortality. Provitamin A carotenoids, particularly β-carotene from certain plant foods are important sources of vitamin A for many populations. During the bioconversion process carotenoids are cleaved by cytosolic enzyme β-carotene 15,15'-monooxygenase 1 (BCMO1). Two polymorphisms (Single Nucleotide Polymorphisms - SNPs) in BCMO1 gene, R267S: rs12934922 and A379V: rs7501331, were identified in ethnic populations of Caucasian, Japanese and Chinese, and it may cause reduced enzyme activity BCMO1 and justify the wide inter-individual differences in bioconversion of β-carotene into vitamin A. The aims of this study were to identify the frequency of polymorphic variants A379V and R267S/A379V of BCMO1 gene in three population groups (whites, blacks and Japanese) and evaluate the relationship between SNPs with serum β-carotene and retinol among three different ethnic groups. Each group was composed of 100 volunteers, with European, African and Japanese ancestry, and 50% were female and 50% male. Were evaluated plasmatic concentrations of β-carotene, retinol, zinc erythrocyte, lymphocytes, C-reactive protein, α-1-acid glycoprotein and dietary intake of Vitamin A. Samples of saliva and oral mucosa exfoliated cells were collected for DNA extraction with subsequent genotyping of SNPs R267S: rs12934922 and A379V: rs7501331 by RT-PCR. The frequencies of allelic variants R267S and A379V at least one T allele for individuals with European ancestry were 63.0% and 44.0%, respectively, African ancestry, 48.0% and 18.0%, respectively, and Japanese ancestry, 21.0 % and 27.0%, respectively. The results show, so unique, that the frequencies of polymorphic variants of the polymorphic variants A379V and R267S BCMO1 gene in Brazilian population groups evaluated depend on ethnicity for both SNPs. The polymorphic variants observed do not seem to ...
Doutor
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Henderson, Susan Ahlstrom. "Vitamin A Status, Anthropometric Measurements, and Food Practices of Women of Childbearing Age and Their Preschool Children in Northeast Brazil." DigitalCommons@USU, 1987. https://digitalcommons.usu.edu/etd/5354.
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Vitamin A nutrition status was evaluated in 110 pairs of women and their preschool children at rural health posts in two different ecological regions of Northeast Brazil. Serum retinol and carotene, weight, height, tricep skinfold and mid-arm circumference were measured from each mother and child. Nutrition knowledge of mothers, socioeconomic living conditions and consumption of retinol and carotene food sources were assessed.
Nine children (8 percent) and one mother had less than acceptable serum retinol (less than 20 μg/dl). Additionally, 21 percent of the children and six percent of the mothers had "low" serum carotene levels. Thirty-seven percent and 57 percent of the children were at or below the tenth percentile for height and weight, respectively, when compared to Brazilian standard tables, and 30 percent were below the tenth percentile of weight for height. When compared to NCHS standard tables, 34 percent were below the tenth percentile for weight/height. Nutrition knowledge was very limited, but opportunities for nutrition education are great as mothers wanted more nutrition and feeding information. Squash, carrots and mangoes were more common sources of vitamin A than were animal sources.
Multiple regression models indicated statistical significance among mothers' serum retinol, survey site, and mothers' weight/height percentile and among mothers' vitamin A intake, survey site, and mothers' ages. The data indicate that vitamin A nutrition status is suboptimal in Northeast Brazil, but appropriate food sources exist. Long-term intervention projects need to focus on increasing the production, distribution, and consumption of preformed vitamin A- and carotene-rich foods.
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Heffernan, Mary Elizabeth Peterson Catherine Ann. "The effects of regular tanning bed use and increased vitamin D status on bone mineral density and serum inflammatory markers in healthy women." Diss., Columbia, Mo. : University of Missouri--Columbia, 2007. http://hdl.handle.net/10355/5024.
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The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Title from PDF of title page (University of Missouri--Columbia, viewed September 10, 2009). Thesis advisor: Dr. Catherine Peterson. Includes bibliographical references.
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Natarajan, Radhika. "Vitamin D metabolites inhibit adipocyte differentiation in ₃T₃-L₁ preadipocytes." Connect to this title, 2008. http://scholarworks.umass.edu/theses/164/.
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Guenther, Isabel. "The relationship between serum leptin, 25-hydroxyvitamin D₃, and body composition." Connect to this title, 2008. http://scholarworks.umass.edu/theses/196/.
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Morkel, Ryan Andrew. "Vitamin B12 and folate enrichment of kefir by Propionibacterium freudenreichii and Streptococcus thermophilus strains." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2339.
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Thesis (MTech (Food Technology))--Cape Peninsula University of Technology, 2016.In South Africa malnutrition exists due to inadequate dietary intake of micronutrients which is one of the major causes of vitamin deficiencies leading to disease. The treatment of malnutrition over the past years has been a considerable burden on the South African economy. Therefore, food fortification is one of the current strategies used to minimize malnutrition by increasing the nutritional value of staple foods. Commercial dairy products and pharmaceutical nutritional products (food supplements) in South Africa have been developed and produced for affluent consumers. Hence the need to develop an affordable fortified dairy product for the majority of South Africans prompted this study aimed at using a “naturally” fortified kefir beverage with vitamin B12 and folate to increase B-vitamins levels. Since Propionibacterium freudenreichii and Streptococcus thermophilus are known to be good producers of vitamin B12 and folate, respectively, and propionibacteria has the ability to grow symbiotically in the presence of lactic acid bacteria, the inclusion of these organisms with the kefir grains was an achievable objective. In order to conduct the analysis of vitamin B12 and folate in the samples, sample extraction and HPLC assay techniques were developed. The extraction of vitamin B12 and folate were achieved by using KCN extraction buffer and the trienzymatic method, respectively. The samples were also subjected to purification and concentration using solid phase extraction for optimum results. All standards and samples were flushed with nitrogen gas and stored for a maximum of 2 weeks at –20°C to prevent B-vitamin deterioration. The HPLC assembly for the vitamin B12 analysis included a Luna C18 column and a diode array detector (DAD) for the detection and quantification. For the folate analysis it included a Zorbax SB-C18 and Luna C18 columns in tandem and the fluorescence detector (FLD) was used for the detection and quantification of THF, 5-CH3-THF and 5-CHO-THF, while the DAD was used for PGA and pteroyltri-γ-L-glutamic acid concentration in the samples.
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Chrisley, Barbara Mc. "Separation and quantitation of the seven forms of vitamin B-6 in plasma and 4-pyridoxic acid in urine of adolescent girls by reverse phase high performance liquid chromatography." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53934.
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The vitamin B-6 status of seemingly healthy adolescent girls was determined using several accepted and proposed parameters in an effort to establish guidelines for status evaluation. HPLC-derived plasma B-6 vitamer [pyridoxal phosphate (PLP), pyridoxine phosphate (PNP), pyridoxamine phosphate (PMP), pyridoxal (PL), pyridoxine (PN), and pyridoxamine (PM)] and 4-pyridoxic acid (4-PA) concentrations and urinary 4-PA levels of 28 white adolescent females, 12-15 years, having radiomonitored plasma PLP concentrations and coenzyme stimulation of erythrocyte alanine aminotransferase activities indicative of adequate status were determined. Mean daily vitamin B-6 and protein intakes of the subjects were 1.48 mg and 78.3 g, respectively. The ranges for plasma B-6 vitamer and 4-PA concentrations for these subjects which had seemingly adequate vitamin B-6 status were as follows: (nmol/L) PLP, 40.9-122.2; PNP, 0-16.1; PMP, 0-8.1; PL, 0- 15.0; PN, 0-21.9; PM, 0-17.8; and 4-PA, 0-55.7. PLP was the predominant plasma B-6 vitamer as well as being the only vitamer found in plasma of all subjects. Urinary 4-PA concentrations of the girls ranged from 0.11-2.50 pmol/mmol creatinine. The B-6 vitamer values of these white adolescent girls should be of use in the establishment of normal ranges for vitamin B-6 status parameters. HPLC methodologies seem to be advantageous for the rapid and accurate assessment of vitamin B-6 status.Ph. D.
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Exebio, Joel. "The Effect of Vitamin D Supplementation on Cardiovascular Risk Factors among Minorities with Type 2 Diabetes." FIU Digital Commons, 2015. http://digitalcommons.fiu.edu/etd/2266.
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The aim of the present study was to determine the effect of vitamin D supplementation (4000 IU or 6000 IU of cholecalciferol daily for 6 months) on fasting plasma glucose, fasting insulin, glycated hemoglobin, and lipid profile in a sample of African-Americans and Hispanics with T2D and vitamin D insufficiency. Seventy five participants were recruited by community outreach. Plasma glucose concentration was measured by hexokinase enzymatic method. Glycated hemoglobin was measured by the DCA2000+ system. Insulin in fasting blood was determined by radioimmunoassay. Plasma total cholesterol, triglycerides, low-density lipoprotein, and high-density lipoprotein cholesterol were assayed by enzymatic methods. Serum vitamin D concentrations were measured with an enzyme-immunoassay kit. Mixed model was used to compare treatment effects and Bonferroni multiple comparison tests was used to detect significant changes from baseline, 3 months, and 6 months on the outcome variables. Significant improvements in serum 25(OH)D levels were seen from baseline to 3 month and 6 months respectively in both treatments (from 22.25 ± 7.19 to 37.34 ± 12.31 and 37.99 ± 13.22, PPP=0.040) was observed. Similarly, a significant change in serum triglycerides was observed at 6 months in the 6000 IU group (from 201.44 ± 91.35 to 172.92 ± 76.87 mg/dl, P=0.037). However, when the model was adjusted for confounders, significance was lost. Vitamin D supplementation did not improve glucose homeostasis in this sample. The positive effect of vitamin D supplementation on lipid profile may be mediated by other cofactors related to vitamin D metabolism.
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Kam, May-sin, and 甘美倩. "Vitamin D and influenza in school children." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B45172407.
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Orton, Sarah-Michelle. "Environmental factors in multiple sclerosis susceptibility and outcome : a focus on vitamin D." Thesis, University of Oxford, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.670043.
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Scherf, Kayla K. "Vitamin D Status of American Adults Age 18 Years and Older: National Health And Nutrition Examination Survey 2001-2002 and 2003-2004." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1225454830.
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Zarini, Gustavo G. "The Effect of Vitamin D3 Supplementation on Kidney Function and Cardiovascular Disease Markers among Hispanics and African Americans with Type 2 Diabetes." FIU Digital Commons, 2017. http://digitalcommons.fiu.edu/etd/3376.
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Serum vitamin D deficiency/insufficiency, Chronic Kidney Disease (CKD) and elevated blood pressure are important health concerns especially among minorities with type 2 diabetes. The effect of vitamin D3 supplementation (cholecalciferol) at 6,000 IU/day (d) vs. 4,000 IU/d on kidney function and cardiovascular disease markers among Hispanics and African Americans with type 2 diabetes and hypovitaminosis D (/ml) was evaluated. Subjects (n=63) were recruited from two clinics in Miami-Dade County, FL. Fasting venous blood and fresh, single-voided first morning urine samples were collected from each participant by a certified phlebotomist and analyzed by Solstas Lab Partners, Davie, FL. Linear mixed models were used to compare the interaction between time and intervention. Least Significant Difference (LSD) comparisons were used to detect significant differences within and between 4,000 IU/d and 6,000 IU/d groups from baseline, 3 and 6 months. In the 4,000 IU/d and 6,000 IU/d groups, a significant increase in serum 25-hydroxy vitamin D [25(OH)D] levels were observed from baseline [(19.9±1.1 ng/mL) and (21.4±1.3 ng/mL)] to 3 months [(36.1±2.2 ng/mL, p3 longer than 6 months may be needed to determine sustained long term effects in kidney and cardiovascular disease markers. Further research could provide more information for translation of these findings into recommendations for individuals with CKD, hypertension and type 2 diabetes. The efficacy of vitamin D3 supplementation as complementary therapy for CKD and blood pressure in minority and other ethnic groups needs further investigation in larger and longer duration randomized controlled trials.
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Chapman, Laurie A. "Interactions of nutrients on methyl mercury toxicity in neuron X spinal chord hybrid cells (NSC-34) and human oligodendrocyte X rhabdomyosarcoma cells (MO3.13)." Thesis, McGill University, 2001. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36888.
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Exposure to methyl mercury (MeHg) is a global concern. Increased chronic exposure to MeHg among fish and marine mammal consuming populations will increase the risk of prenatal exposure and as a result, the risk of infant brain damage and neurotoxcity. It is therefore important to understand the role of environmental factors, such as nutrition, in determining susceptibility to MeHg toxicity. Three nutrients (selenium (Se), vitamin C and vitamin E) were selected for examination of their interactions with the mechanisms of McHg cytotoxicity in vitro. Two hybrid neural cell lines (M03.13 and NSC-34) were evaluated for their usefulness in the study of MeHg cytotoxicity. Sixteen toxic endpoints were selected for investigation of growth, viability, structure and biochemistry. Both cell lines responded to MeHg exposure in a dose dependent manner for the majority of endpoints suggesting that both MO3.13 and NSC-34 cells undergo structural and biochemical changes during exposure to McHg, but that MO3.13 cells are more sensitive to DNA, mitochondria) membrane damage and glutathione (GSH) depletion and that NSC-34 cells are more sensitive to protein damage and apoptosis. Se exposure lessened the MeHg-induced decrease in DNA and GSH concentrations in both cell lines. In NSC-34 cells, Se also increased F-actin concentrations and prevented an increase in caspase-3 activity. Se may alter the mechanism of cell death by preventing McHg disruption of DNA replication thus maintaining the production and function of peptides (GSH) and protein (polymerized actin) that aid in MeHg detoxification and neural function. In NSC-34 cells, vitamin C prevented the induction of caspase-3 activity and lessened DNA damage and GSH depletion. Vitamin E lessened GSH depletion and lessened G-actin depletion. Both vitamin C and E improved GSH status, but vitamin C also delayed McHg damage of DNA and prevented early signs of apoptosis suggesting these two vitamins interfere with MeHg metabolism by diffe
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Wu, Jason H. Y. "Vitamin E and atherosclerosis : investigation of novel biological activities and metabolism of gamma-tocopherol in humans." University of Western Australia. School of Medicine and Pharmacology, 2006. http://theses.library.uwa.edu.au/adt-WU2007.0019.
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[Truncated abstract] Current understanding of atherosclerosis suggests that it is a chronic inflammatory disease, and that increased oxidative stress may be an important pathological event contributing to the disease process. There has been interest in the ability of dietary derived nutrients such as vitamin E, to act as antioxidants and protect against atherosclerosis. Despite promising epidemiological data which suggested benefits from a higher intake of &alpha-tocopherol (&alphaT), one of the major forms of dietary vitamin E, for protection against atherosclerosis, large scale, randomised controlled trials have generally shown no protective effect of high dose &alphaT supplementation. Recent studies suggest that the other major dietary tocopherol isomer, &gamma-tocopherol (&gammaT), may possess biological activities not shared by &alphaT. Supplementation with &gammaT, or mixtures of tocopherols rich in &gammaT, have shown biological activities that may help protect against atherosclerosis. The aim of this PhD project is to further characterise the biological relevance of ?T for protection against CVD... Both ?- and mixed tocopherol supplementation resulted in reduced plasma F2-isoprostanes (P < 0.001 and P = 0.001, respectively) but did not affect 24 hour urinary F2-isoprostanes and erythrocyte antioxidant enzyme activities. Neither &alphaT nor mixed tocopherol supplementation affected any measured plasma markers of inflammation. The tocopherol supplementation also did not affect COX-2 activity as assessed by 14 stimulated whole blood prostaglandin E2 synthesis, and urinary prostacyclin metabolite output. Compared to the placebo group, stimulated neutrophil leukotriene B4 (LTB4) production decreased significantly in the mixed tocopherol group (P=0.02) but not in the &alphaT group (P=0.15). The ability of both pure &alphaT and mixed tocopherol supplementation to reduce systemic lipid peroxidation in patients with type 2 diabetes, suggests potential benefits of vitamin E supplementation in this population. However, despite decreasing oxidative stress, our results also suggests that in populations with well controlled type 2 diabetes, supplementation with either &alphaT, or mixed tocopherol rich in &gammaT, is unlikely to confer further benefits in reducing systemic inflammation. Future research into the possible unique biological activity of different tocopherol isomers other than &alphaT, for example, their ability to affect the 5-LO pathway and production of inflammatory mediators such as LTB4, is warranted.
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Poirier, Johanne 1959. "The effects of selenium and vitamin E intake on diet-induced oxidative stress and hyperlipidemia /." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31526.
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To examine the effects of fat composition and supplemental vitamin E (Vit E) and selenium (Se) on in vivo lipid peroxidation, diet-induced hypercholesterolemia, and glutathione (GSH) metabolism, male Syrian hamsters were fed for three weeks butter fat (BF-) or fish oil- (FO-)based diets supplemented with Vit E and/or Se. The effect of supplemental Vit E and Se on tissue lipid peroxidation (LPO), glutathione peroxidase (GSH-Px) activity and GSH concentrations differed between heart and liver and also was affected by dietary fat. The reduced glutathione/oxidized glutathione (GSH/GSSG) ratio was more consistently associated with tissue lipid peroxidation than was tissue Vit E content. Plasma lipids were lowered with supplemental Se and Vit E. Se supplementation, however, exerted a more potent hypolipidemic effect than Vit E. A pro-oxidative action of Se in hearts of FO-fed hamsters was noted, which was inhibited by supplemental Vit E. Hence, the combination of Vit E and Se may offer the most benefit against diet-induced oxidative stress and hyperlipidemia.
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Martini, Fabiana Cristina Camargo. "Comparação entre a disponibilidade de ferro na presença de vitamina A e beta-caroteno em alimentos e medicamentos." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-02012003-133746/.
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O ferro e a vitamina A são nutrientes essenciais para o desenvolvimento e a manutenção do organismo. Este trabalho teve por objetivos verificar a disponibilidade de ferro na presença de vitamina A, presente nos alimentos: feijão comum (F), fígado bovino (Fi) e cenoura (C) e medicamentos: Fer-In-Sol(Fer), Arovit(A) e Neutrofer (N), bem como suas combinações; quantificar a composição centesimal, minerais, antinutricionais, ferro heme e não-heme, retinol e beta-caroteno, dos alimentos e suas combinações com medicamentos. A quantidade de medicamentos adicionada aos alimentos foi calculada em função de uma prévia análise da composição de ferro e beta-caroteno dos alimentos. As quantidades de ferro sulfato (Fer1) e ferro aminoquelato (N1) correspondem à quantidade de ferro encontrada na amostra de feijão. Fer2 e N2 correspondem à concentração de ferro encontrada na amostra de fígado. A vitamina A (A1) foi calculada através da conversão do beta-caroteno da cenoura. Dos alimentos e medicamentos, originaram as seguintes combinações: (C), (C+A1), (C+N1), (C+N2), (C+Fer1), (C+Fer2), (C+F), (F), (F+A1), (F+Fer2), (F+N2), (F+Fi), (Fi), (Fi+A1), (Fi+Fer1), (Fi+N1) e (Fi+C). Os resultados obtidos foram analisados estatisticamente através do teste de Tukey (5%), empregando-se o programa SAS. A amostra (C) apresentou maior umidade (88,12 %) e beta-caroteno (6,42 mg/100g). A amostra (F), maior concentração de carboidratos (10,68 %), fibra dietética (7,47 %), sendo também determinados os taninos (0,05 %) e ácido fítico (2,71 mg/g). A amostra (Fi), maior concentração de fração cinza (2,13 %), extrato etéreo (7,01 %), proteínas (31,35 %), sendo também determinados vitamina A (71285 UI/100g), ferro heme (31,85 mcg/g) e concentração de ferro dialisável (8,10 mg/kg). Foram avaliadas as concentrações de minerais. As concentrações de vitamina A das amostras variaram de 2247 UI/100g (C+F) a 71285 UI/100g (Fi), e foram calculadas através da conversão da concentração de retinol e de beta-caroteno das amostras analisadas. Foram determinadas as quantidades de ferro heme e não-heme, somente para as amostras contendo fígado. Esses valores variaram de 13,06 mcg/g (F+Fi) a 31,85 mcg/g (Fi) e 2,54 mcg/g (Fi+C) a 9,48 mcg/g (Fi+Fer1), respectivamente. Para quantificar a porcentagem de ferro disponível das amostras, foi realizada a diálise do ferro "in vitro". Para o cálculo da diálise, nas amostras contendo fígado, considerou-se o ferro não-heme, mais 25 % da concentração de ferro heme das amostras. A concentração de ferro dialisável variou de 0,12 mg/kg (F) a 8,10 mg/kg (Fi). Não houve influência de outros minerais avaliados sobre a disponibilidade de ferro. Os antinutricionais taninos e ácido fítico exerceram efeito inibitório sobre a disponibilidade de ferro. A vitamina A e o beta-caroteno exerceram efeito positivo sobre a porcentagem de diálise do ferro. A cenoura e o fígado apresentaram melhor porcentagem de ferro dialisável do que os respectivos medicamentos em concentrações semelhantes. Portanto, pode-se concluir que houve influência da vitamina A sobre a diálise do ferro, sendo as misturas contendo fígado as que obtiveram melhores concentrações de ferro dialisável, e que, de acordo com as quantidades necessárias para se atingir as exigências diárias de ferro, são viáveis ao consumo.Iron and vitamin A are essential nutrients for the development and maintenance of human body. This study aims to check the availability of iron in presence of vitamin A, in carrot, bean, bovine liver and in the medicines Arovit Neutrofer and Fer-In-Sol, as well as in their combinations. Also it aimed to quantify the proximate composition, minerals, antinutritionals, heme and nonheme iron, retinol and beta-carotene in foods and their combinations with medicines. The amount of medicines added to foods was figured based on a previous analysis of the iron and beta-carotene food composition. The amount of iron sulfate (Fer1) and iron aminoquelate (N1), corresponds to the amount of iron found in the bean samples. Fer2 and N2 correspond to the iron concentration found in the bovine liver samples. Vitamin A was figured through carrot beta-carotene conversion. The combination of foods and medicines showed: (C), (C+A1), (C+N1), (C+N2), (C+Fer1), (C+Fer2), (C+F), (F), (F+A1), (F+Fer2), (F+N2), (F+Fi), (Fi), (Fi+A1), (Fi+Fer1), (Fi+N1) and (Fi+C). The results obtained were analyzed statistically through the Tukey test (5%), making use of the SAS System. The carrot samples showed higher moisture (88,12 %) and beta-carotene (6,42 mg/100g). The bean samples showed higher concentration of carbohydrates (10,68 %), dietetic fiber (7,47 %), being also determined the tannins (0,05 %) and phytic acid (2,71 mg/g). The bovine liver samples showed higher concentration of ash (2,13 %), crude fat (7,01 %), proteins (31,35 %), being also determined vitamin A (71285 UI/100g), heme iron (31,85 mcg/g) and iron available. Mineral concentrations were also measured. The vitamin A concentrations ranged from 2247 UI/100g (C+F) to 71285 UI/100g (Fi) and it was figured through the conversion of the retinol and beta-carotene concentration of the samples. The heme and nonheme iron amount were determined only in the liver sample, and ranged from 13,06 mcg/g (F+Fi) to 31,85 mcg/g (Fi) and from 2,45 mcg/g (Fi+C) to 9,48 mcg/g (Fi+Fer1) respectively. The "in vitro" iron dialyse was used to quantify the amount of iron available in the samples. In the liver samples, it was considered the nonheme iron plus 25 % of the heme iron part. The iron available concentration ranged from 0,12 mg/kg (F) to 8,10 mg/kg (Fi). There was no minerals influence on the iron availability. The antinutricional tannins and phytic acid had an inhibitor effect on the iron availability. Vitamin A and beta-carotene had a positive effect on the iron availability. The carrot and bovine liver showed better iron dialyze percentage than their respective medicines of similar concentration. Therefore, it was concluded that vitamin A had a positive effect on the iron availability and, being the bovine liver samples the ones which showed better iron available concentration and are feasible to consume according to the daily needs of iron.
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Murphy, Stephanie A. "Effects of selenium and vitamin B-6 on growth of chemically- induced transplanted tumors in BALB/c inbred mice." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/43906.
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Male weanling inbred, mice were inoculated with
fibrosarcoma cells (hindquarter) originally produced by 2-methylcholanthrene. Before inoculation, mice were randomly divided into three groups of 24 and one of 12
(control). After a one week acclimation period, each group was fed a diet containing either suboptimal vitamin B-6, 0.5 mg/kg diet; adequate, 7.0 mg/kg diet; or excess, 100 mg/kg diet. Controls were fed the adequate vitamin. B-6 diet. Twenty-four hours after
tumor cell inoculation, a series of sodium selenite injections (0.5 μg/.10 mL) were given to half of each treatment group and all controls. Mice were sacrificed
two wk after tumor inoculation. Tumors were excised and weighed. Selenium-treated mice had significantly smaller tumors as compared to untreated mice regardless
of vitamin B-6 treatment. The smallest tumors were
found in the selenium-treated group maintained on
adequate B-6, while the largest tumors were developed
by mice on the excess B-6 diet without selenium treatments.
All groups had similar blood selenium levels as
measured by gas chromatography. Tumor selenium levels,
analyzed by atomic absorption, were significantly
higher for untreated groups than selenium-treated
groups (larger tumor size). The excess and adequate
vitamin B-6 selenium-treated groups had significantly
lower tumor selenium levels than the adequate vitamin
B-6 untreated group. Plasma pyridoxal phosphate
(concentrations) determined radiometrically and tumor
vitamin B-6 levels determined microbiologically, related directly to dietary treatments. Sodium selenite
injections and adequate vitamin B-6 diets reduced the
size of fibrosarcomas in BALB/c inbred mice.Master of Science
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Leonard, Franciska. "Modulation of the intestinal vitamin D receptor and calcium ATPase activity by essential fatty acid supplementation." Diss., University of Pretoria, 1999. http://hdl.handle.net/2263/24269.
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Chávez, Verónica. "Determination of seric retinol levels in relation to consumed diet and the prevalence of anemia in preschool- and school-aged children in the communities of Cuambo and La Rinconada, Imbabura province." BYU ScholarsArchive, 2003. https://scholarsarchive.byu.edu/etd/5347.
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In this investigation the seric retinol levels were determined in order to relate them with consumed diets by preschool- and school-aged children and the prevalence of anemia in the communities of Cuambo and La Rinconada, Imbabura province, in order to later compare them with reference values. Blood samples were taken from 74 children from the two communities, 30 in La Rinconada and 44 in Cuambo, beneficiaries of the Benson Institute, to determine retinol, ferritin, hemoglobin, and hematocrit. Also, a 24-hour record with frequency of food consumption survey was given to the studied children's parents, making a sample of 56 families. Among the principal results we can determine that the inhabitants of the two communities have a low consumption of foods rich in Vitamin A compared to recommendations, despite having family gardens that include a large quantity of foods rich in this micronutrient.
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Germano, Romilda Maria de Arruda. "Disponibilidade de ferro na presença do B-Caroteno e o efeito dos interferentes em combinações de alimentos." Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11141/tde-19082002-152718/.
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No mundo as deficiências de ferro e de vitamina A atingem números alarmantes, afetando tanto a população com nível sócio-econômico mais baixo quanto aqueles mais favorecidos. O presente trabalho teve por objetivos avaliar a disponibilidade de ferro na presença do b-caroteno em combinações de alimentos fontes de ferro (espinafre, feijão e ovo) e de b-caroteno (cenoura, abóbora e couve), de custo relativamente baixo, as quais originaram nove misturas, assim denominadas: M1= ovo e abóbora; M2= espinafre e abóbora; M3= espinafre e couve; M4= ovo e couve; M5= espinafre e cenoura; M6= ovo e cenoura; M7= feijão e cenoura; M8= feijão e abóbora e M9= feijão e couve. As misturas, após cocção foram analisadas quanto à composição centesimal, teor de ácido oxálico, ácido fítico, taninos, minerais, diálise de ferro in vitro e determinação do teor de b-caroteno. Os dados foram analisados estatisticamente (Tukey 5%), pelo programa SAS. As misturas M1, M4 e M6 apresentaram o menor teor de fibra, com 1,32, 1,35 e 1,54 g/100g e os maiores resultados para proteína, 6,80, 7,13 e 6,59 g/100g respectivamente, como também para extrato etéreo 4,77, 4,79 e 5,73 g/100g. O teor de ácido oxálico variou de 0,14 a 0,27%, sendo que as misturas com espinafre apresentaram os maiores resultados; o teor de ácido fítico variou de 0,00 a 1,03 mg/g, sendo que as maiores concentrações predominaram nas amostras com feijão; o teor de taninos variou de 0,01 a 0,14 apresentando maiores teores, nas misturas com espinafre.O b-caroteno apresentou teores variando de 4,62 a 26,10 mg/100g. Quanto aos minerais observou-se variações de 0,19 a 1,00 g/Kg para fósforo; 0,82 a 1,37 g/Kg para potássio; 0,17 a 0,92 g/Kg para cálcio; 0,03 a 0,18 g/Kg para magnésio; 0,19 a 0,93g/Kg para enxofre; 0,00 a 0,65 mg/Kg para o cobre; 6,87 a 14,99 mg/Kg para o ferro; 0,00 a 13,08 mg/Kg para manganês e 2,88 a 7,16 mg/Kg para o zinco. A diálise de ferro apresentou variações de 3,39 a 31,11% , sendo que o melhor resultado apresentou-se na M6. Pode-se concluir que a fibra atuou como fator limitante na absorção do ferro. E, misturas com ovo, principalmente a M6, aumentaram a disponibilidade do ferro, sendo que, a proteína e o extrato etéreo atuaram de forma mais significativa no aumento da absorção, quando comparados ao b-caroteno.In the world, iron deficiency and vitamin A deficiency reach alarming numbers, affecting population with level economic-social lower as well as people in better positions. This research aims to estimate the iron availability in the presence of b-carotene in food mixtures irons sources (spinach, bean and egg) and b-carotenes sources (carrot, pumpkin and cabbage), with low prices, that have resulted nine mixtures, denominated: M1= egg and pumpkin; M2= spinach and pumpkin; M3= spinach and cabbage; M4= egg and cabbage; M5= spinach and carrot; M6= egg and carrot; M7= bean and carrot; M8= bean and pumpkin and M9= bean and cabbage. In this food mixtures, after cooking, were studied proximate composition, levels of oxalic acid, phytic acid, tannin, minerals, in vitro dialyzability of iron and levels of b-carotene. The statistical analysis was determinate (Tukey 5%) by SAS System. The food mixtures M1, M4, M6 showed low levels of dietetic fiber, 1,32, 1,35, 1,54 g/100g and the bigger results to protein 6,80, 7,13, 6,59 g/100g and to crude fat 4,77, 4,79, 5,73 g/100g, respectively. The oxalic acid ranges to 0,14 from 0,27%, with bigger results in food mixtures with spinach; phytic acid ranges to 0,00 from 1,03 mg/g, with high levels in beans samples; the tannin ranges to 0,01 from 0,14 with high levels in spinachs samples. b-carotene showed levels ranges to 4,62 from 26,10 mg/100g. With regard to minerals, its ranges to 0,19 from 1,00 g/Kg in phosphorus; to 0,82 from 1,37 g/Kg in potassium; to 0,17 from 0,92 g/Kg in calcium; to 0,03 from 0,18 g/Kg in magnesium; to 0,19 from 0,93g/Kg in sulfur; to 0,00 from 0,65 mg/Kg in cupper; to 6,87 from 14,99 mg/Kg in iron; 0,00 a 13,08 mg/Kg in manganese and to 2,88 from 7,16 mg/Kg in zinc. In vitro dialyzability of iron ranges to 3,39 from 31,11%, and the best result was M6. Its concluded that dietetic fiber was an inhibitor in the irons absorption. And, food mixtures with egg, mainly M6 (egg and carrot), increased iron availability and that crude protein and crude fat were more significant in absorptions increase than b-carotene.
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Cruz-Espaillat, Grisseel A. "A Cross-Sectional Study: Dietary Micronutrient Levels in Allied Health and Nursing Students." ScholarWorks, 2015. https://scholarworks.waldenu.edu/dissertations/350.
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The adequate intake of micronutrients is important to maintain optimal health and prevent nutritional disorders and chronic disease. Studies have shown that medical students often reduce self-care behaviors and lack adequate dietary intake, leading to nutritional deficiencies. In this quantitative cross-sectional study, measurements of micronutrient levels in a sample of allied health and nursing students were compared to Recommended Daily Allowance (RDA) values. NutritionQuest Data-on-Demand System was used to analyze nutrients and food group intake. The postpositivist paradigm was used to examine how the independent and dependent variables relate to each other. Using a one-sample t test, a comparison of average micronutrient intake among study participants with RDA values for those micronutrients showed that average micronutrient intake in the study population was higher than recommended values. Two sample t-test results showed no significant difference in average intake of micronutrients among participants with high and low income levels, or with high and low stress levels. As the normality assumption was not satisfied by the outcome variables, nonparametric tests were used to evaluate hypotheses. While this finding does not support the original hypothesis, it could have implications for the role of allied health and nursing practitioners in the care of both their patients and members of their medical team. Conversely, an assumption of this study was that a high level of similarity between the traditional medical student population and the allied health and nursing population in terms of nutritional habits may have led to a flaw in the overall research hypothesis. The detection of micronutrient deficiencies in students can bring awareness to improve nutritional intake and initiate a change in how public health officials advocate healthy and balanced diets.
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Goetz, Hilary Jane. "Development and application of an HPLC-MS/MS method for the characterization and quantification of a-retinyl esters and vitamin A in human plasma after consumption of a-carotene." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1408551701.
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Syphard, James Eric. "Sports supplement database /." Link to this database on the INTERNET, 2003. http://sportsupplementdb.project.cisat.jmu.edu/.
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Nälsén, Cecilia. "Measurement and Evaluation of Antioxidant Status and Relation to Oxidative Stress in Humans." Doctoral thesis, Uppsala University, Clinical Nutrition Research, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6742.
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Numerous diseases are associated with reduced antioxidant defence and oxidative stress. The antioxidant defence includes dietary and endogenous antioxidants and involves complex interactions between them. The effects of dietary factors on antioxidant status and oxidative stress of healthy humans were investigated in the studies described in this thesis. Assays of plasma antioxidant capacity encompass interactions between various antioxidants. Although uric acid has an unclear function as an antioxidant, it is a major determinant of antioxidant capacity. We measured antioxidant capacity in the presence and absence of uric acid to provide more information on the application of measures of antioxidant capacity. Individuals with high dietary intakes of various antioxidants and antioxidant rich foods, especially when combined, had higher plasma antioxidant capacities than those with lower antioxidant intakes. However, there were no associations between dietary intake of antioxidants or antioxidant rich foods and the plasma concentration of F2-isoprostanes, which is considered a reliable biomarker for oxidative stress. Intakes of various doses of a mixture of bilberry juice and black tea, rich in flavonoids for four weeks, increased antioxidant capacity in some groups, but urine levels of F2-isoprostanes were not affected. There were substantial individual variations in responses to the drinks related to baseline antioxidant capacity. Supplementation with eicosapentaenoic acid and docosahexaenoic acid decreased the plasma levels of F2-isoprostanes, but not prostaglandin F2α formation or antioxidant capacity.
It was concluded that a high intake of foods rich in antioxidants is related to improved antioxidant status. After intake of foods rich in antioxidants, the antioxidant status may increase, but with considerable individual variation in the responses, which warrants further investigation. Lipid peroxidation in vivo is not easily affected by dietary antioxidants in healthy humans. Although n-3 fatty acids are highly unsaturated, they reduce nonenzymatic free radical-catalyzed lipid peroxidation, but not enzymatic lipid peroxidation.
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Favaro, Patricia Barbosa. "Associação entre deficiência de cobalamina e folato e presença dos polimorfismos MTR A2756C e MTRR A66G em gestantes e seus recém nascidos." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9136/tde-12012018-095817/.
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A metionina sintase redutase (MTRR) catalisa a redução da cobalamina (Cbl) oxidada a metilcobalamina. Em presença de folato, a metionina sintase (MTR) utiliza a metilcobalamina como cofator na metilação da homocisteína (tHcy) a metionina. O objetivo deste estudo foi avaliar os efeitos dos polimorfismos MTR A2756G e MTRR A66G nas concentrações dos metabólitos marcadores de deficiência de Cbl e folato em gestantes e neonatos. Os genótipos dos polimorfismos MTR A2756G e MTRR A66G foram obtidos por PCR-RFLP. O genótipo MTR 2756AA foi relacionado aos maiores valores de tHcy em gestantes e MMA em neonatos. Gestantes com genótipos MTRR 66AG e GG e com menores concentrações de Cbl apresentaram maior risco de apresentar concentrações elevadas de tHcy. Neonatos com genótipos com MTRR 66AG e GG apresentaram menores valores de SAM. Os polimorfismos MTR A2756G e MTRR A66G interferem nas reações dependentes de Cbl e folato em gestantes e neonatos.Methionine synthase reductase (MTRR) catalyzes the reductive reaction of oxidized cobalamin to methylcobalamin. When folate is present, methionine synthase (MTR) uses methylcobalamin cofactor at homocysteine to methionine methylation process. The aim of this study was to evaluate the effects of MTR A2756G and MTRR A66G polymorphisms on total homocysteine (tHcy), methylmalonic acid (MMA), S-adenosylmethionine (SAM) concentrations and SAM/SAH ratio in Brazilian pregnant women and their newborns. Genotypes of two polymorphisms were determined by PCR-RFLP. MTR 2756AA genotype was associated with higher tHcy and MMA levels in mothers and babies, respectivelly. Lower cobalamin concentrations associated with MTRR 66AG and GG genotypes increased risk to elevated tHcy levels in pregnant women. The SAM levels were lower in neonates with MTRR 66AG e GG genotypes. The polymorphisms MTR A2756G and MTRR A66G could affect cobalamin and folate dependent reactions in pregnant women and newborns.
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Marks, Amanda R. "Nutrition, Vitamin D and Refractive Error." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1275397144.
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Mark, Sean. "Vitamin D status and recommendations to improve vitamin D status in Canadian youth." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=92287.
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Little is known regarding the vitamin D status of Canadian youth. Our objectives were: (i) to describe the vitamin D status of Québec youth using a representative sample; (ii) examine the relative contributions of diet, physical activity and fat mass to the variance in plasma 25-hydroxyvitamin D{25(OH)D}, the best biomarker of vitamin D status; and (iii) examine the influence of household income and food insecurity on the intakes of dietary vitamin D, calcium and dairy foods.To describe vitamin D status, we used data from a cross-sectional survey representative of Québec youth aged 9, 13 and 16, the Québec Child and Adolescent Health and Social Survey (QCAHS). For the second objective, 159 youth, aged 8-11 whose parents (at least one) were obese or had the metabolic syndrome were used for cross-sectional analysis in the Québec Adipose and Lifestyle InvesTigation in Youth (QUALITY). Fat mass was measured using Dual X-ray Absorptiometry (DXA) and physical activity was assessed by accelerometer. Finally, we analyzed data from the Canadian Community Health Survey (CCHS), a sample of 8960, 9-18-year-olds representative of Canadian youth for whom a single 24 hour dietary recall, measured height and weight, sociodemographic and information on food insecurity were available.
Greater than 90% of youth had sub-optimal vitamin D levels {plasma 25(OH)D < 75 nmol} at the end of winter and beginning of spring in both the QUALITY and QCAHS study. In the QCAHS study, older youth had a higher prevalence of vitamin D deficiency {25(OH)D < 27.5 nmol} (> 10%) than younger youth and girls from low income households had lower plasma 25(OH)D concentrations. In the QUALITY study, milk consumption and physical activity had modest associations with plasma 25(OH)D corresponding to 2.9 nmol/L and 2.1 nmol/L higher plasma 25(OH)D per standard deviation increase in these exposures, respectively. In the CCHS study, we found evidence that milk intake was being displaced by sweetened beverages amongst low income boys and food insecure girls.
Population wide measures to increase dietary vitamin D intake should be examined in Canadian youth.
Il y a peu de connaisances concernant le statut vitamin D des jeunes Canadiens. Nos objectifs étaient de: (i) décrire le statut vitamin D des jeunes Québécois en utilisant un échantillon représentatif; (ii) examiner la contribution de la diète, l'activité physique et l'adiposité a expliquer la variance du 25-hydroxyvitamin D, {25(OH)D.}, le meilleur biomarqueur du statut vitamine D; et (iii) examiner l'influence du statut socio-économique et l'insécurité alimentaire sur le consommation des produits laitiers, du calcium et de la vitamine D alimentaire.
Pour décrire le statut vitamine D on a utilisé les données transversales d'un échantillon représentatif des jeunes Québecois agés de 9, 13 et 16 ans. Pour le deuxième objectif, 159 jeunes, âgés 8-11 ans avec des parents (au moins un) qui étaient obèses ou avaient le syndrome métabolique etaient utilisés pour une analyse transversale dans l'étude Québec Adipose and Lifestyle InvesTigation in Youth (QUALITY). Le tissu adipeux a été mesuré avec le dual X-ray absorptiometry (DXA) et l'activité physique était mésurer par accéléromètre. Finalement, on a utilisé des données du Canadian Community Health Survey (CCHS), un échantillon de 8960 jeunes, agés de 9-18 ans qui avaient un rappel alimentaire de 24 heures, le poids et la taille mesuré, l'information sociodémograhique et le statut de sécurité alimentaire.
Dans l'étude QUALITY et le QCAHS plus de 90% des jeunes avaient un statut de vitamine D sub-optimal {plasma 25(OH)D < 75 nmol} à la fin de l'hiver et au début du printemps. Dans l'étude QCAHS, les adolescents avaient une prévalence de déficience de vitamine D élevé {25(OH)D < 27.5 nmol} (> 10%) et les filles venant des foyers défavorisés avait des niveaux de vitamine D plus bas. Dans l'étude QUALITY, un augmentation d'un écart-type de la consommation du lait et l'activité physique était associée avec une augmentation du niveau de vitamin D de 2.9 nmol/L and 2.1 nmol/L respectivement. Dans l'étude CCHS nous avons remarqué que les garçons de milieux défavorisés et les filles avec une insécurité alimentaire consommaient moins de lait et le lait étaitremplacé par les breuvages sucrés.
Des mesures pour augmenter la consommation de vitamine D parmi les jeunes Canadiens devraient être examinées.
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Al-Saleh, Maysoon Ahmed Saad. "Studies of vitamin A in nutrition and cancer." Thesis, University of Glasgow, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.236066.
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Zolfaghari, Sara S. "The relationship between folic acid, vitamin B12, and vitamin B6 intakes and depression in women who use hormonal oral contraceptives." Thesis, California State University, Long Beach, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1604887.
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Depression is a leading cause of disability and mortality worldwide, especially for women. No nutrition recommendations exist for depression. Oral contraceptives (OCs) have become the leading form of pregnancy prevention in the United States. Studies have associated OC use with impaired nutrient status, specifically folate, vitamin B12, and vitamin B6, which also affect brain functions. Dietary folate, vitamin B12, and vitamin B6 self-reported intakes were used to determine the relationship between depression in women who used OCs (n = 34) in a selected cohort ( n = 409) from the National Health and Nutrition Examination Survey, 2003–2008. OC users were more depressed than non-OC users; depression was associated with various quartile levels of vitamin intake (p <.001). No benefit was observed with intakes which exceeded RDAs for non-OC users; OC users were less depressed when intakes exceeded RDAs for folate, vitamin B12, and vitamin B6 by 13%, 75%, and 7%, respectively.
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Clark, W. Andrew. "Falls and Vitamin D." Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/2526.
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Clark, W. Andrew. "Falls and Vitamin D." Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/2528.
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Yap, Constance Meng Yee. "Vitamin D supplementation in human pregnancy." Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/13687.
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Vitamin D deficiency is a prevalent problem worldwide and data suggest that maternal vitamin D deficiency is associated with adverse maternal and offspring non-skeletal outcomes. We performed a double-blind randomised controlled trial to establish the effect of high-dose (5000 IU) vitamin D supplementation on glucose metabolism measured by the 75g oral glucose tolerance test (OGTT) and insulin resistance on the homeostasis model assessment (HOMA-IR). Additionally, we evaluated the vitamin D status of a multiethnic pregnant population and determined the predictive factors for vitamin D deficiency. Finally, we determined the association between maternal vitamin D status and intrauterine and neonatal growth, and the effects of high-dose vitamin D supplementation on the same parameters. We identified that low maternal vitamin D status at baseline was associated with more adverse glucose tolerance on the OGTT. High-dose vitamin D supplementation improved maternal and infant 25-hydroxyvitamin D (25OHD) but did not improve glucose levels and HOMA-IR. Nearly half of our cohort had 25OHD<50nmol/L. Ethnicity, Δ skin reflectance and vitamin D containing pregnancy multivitamin use predicted baseline vitamin D status. Maternal vitamin D status during pregnancy was not associated with intrauterine growth and high-dose vitamin D supplementation did not affect intrauterine or birth measures.
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Bruns, Nicholas Joseph. "Humoral and cell-mediated immunity in vitamin A-deficient lambs." Diss., Virginia Polytechnic Institute and State University, 1988. http://hdl.handle.net/10919/53919.
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Antigen-specific and polyclonal serum immunoglobulin G (IgG) concentrations were measured in control (Con), vitamin A-deficient (A-def), and vitamin A-repleted (A-rep) lambs. In Trial, I ewe lambs were injected with primary and secondary antigenic challenges of ovalbumin (1mg) and lysozyme (.1mg). The A-def lambs were then repleted with vitamin A and all lambs were injected with primary and secondary antigenic challenges of human gamma globulin (HGG) (.1mg). In Trial II Con and A-def wether lambs were given primary and secondary antigenic challenges of ovalbumin (20μg). Half of the A-def lambs were then repleted with vitamin A. All lambs were subsequently given a primary and secondary challenge of HGG (20 μg). Spleen wt were similar for all treatments in Trial I while A-def V lambs in Trial II had greater spleen wt (P<.01) than Con or A-rep lambs. Polyclonal serum IgG concentrations were unaffected by treatment in Trial I while in Trial II concentrations were greater (P<.05) in the A-def lambs during the HGG challenge period. Antigen-specific IgG concentrations in both trials tended to be greater in the Con lambs towards the end of both the ovalbumin (Trial I and II) and lysozyme (Trial I) challenge periods. Control and A-rep lambs in Trial I responded similarly to the HGG challenges. In Trial II both the A-def and A-rep lambs had lower (P<.10) HGG specific serum IgG concentrations on the last 3 wk of the HGG challenge period as compared to A-def lambs. Humoral immune function appears to be impaired in A-def lambs and a 2-wk repletion period was not sufficient in this study to restore humoral immune function to normal levels.Ph. D.
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King, Joan M. "Riboflavin Photosensitized Singlet Oxygen Oxidation of Vitamin D." The Ohio State University, 1996. http://rave.ohiolink.edu/etdc/view?acc_num=osu1392814029.
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Padilla, Licza. "Studies on vitamin C nutrition in various conditions of cattle." Kyoto University, 2006. http://hdl.handle.net/2433/136499.
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Kyoto University (京都大学)0048
新制・課程博士
博士(農学)
甲第12612号
農博第1584号
新制||農||933(附属図書館)
学位論文||H18||N4183(農学部図書室)
UT51-2006-S620
京都大学大学院農学研究科応用生物科学専攻
(主査)教授 矢野 秀雄, 教授 久米 新一, 教授 今井 裕
学位規則第4条第1項該当
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Barake, Roula. "Correlates and consequences of vitamin D status in older people." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86736.
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It is well established that vitamin D contributes to bone health. New evidence from cross-sectional and prospective cohort studies and a few clinical trials suggest that vitamin D status may play a role in functional capacity declining with age; however, there are some gaps in these studies yet to be examined. Little is known about vitamin D status in healthy, free-living, older people in North America. Older individuals may be more vulnerable due to low vitamin D intake and limited endogenous synthesis. Thus, the objectives of this thesis were to (i) determine the distribution of serum 25 hydroxy vitamin D [25(OH)D] concentrations in healthy older people living in Québec and determine how season, age, sex and supplement consumption affect this distribution; (ii) determine to what extent vitamin D intake from foods, supplements and proxy measure of sunlight exposure explain the variation in serum 25(OH)D concentrations, controlling for the effects of age and sex; and determine the dietary predictors of optimal concentration of 25(OH)D; and (iii) examine whether vitamin D status can predict change in functional decline capacity over 1 and 2 years, controlling for season and other potential confounders. Data for this study have been obtained from a random sampling of 405 participants from the NuAge cohort study of 1793 independently-living men and women aged 68 to 82 years at baseline. The NuAge sample is a stratified sample of participants in three age categories 70 ± 2 years, 75 ± 2 years and 80 ± 2 years with approximately equivalent numbers of men and women in each group. For objective (i), a cross-sectional design was applied. Serum 25(OH)D was assessed using radioimmunoassay. Data were analyzed controlling for age, sex, season and other potential confounders. For objective (ii), six 24-hour recalls were obtained for the same subjects as the first study also in a cross-sectional design. In addition to nutrient intake, foods were grouped into 6 food groupIl est bien établi que la vitamine D contribue à la santé osseuse. Des données récentes d'études transversales, de cohortes prospectives et d'essais cliniques suggèrent que la vitamine D pourrait jouer un rôle dans la diminution des capacités fonctionnelles avec l'âge; toutefois, certaines lacunes de ces études n'ont toujours pas été étudiées. On sait peu de choses au sujet des niveaux de vitamine D chez les personnes âgées autonomes, en bonne santé, vivant en Amérique du Nord. Ces personnes peuvent être plus vulnérables aux carences d'une part à cause d'un faible apport en vitamine D et, d'autre part, à cause d'une synthèse endogène limitée. Ainsi, les objectifs de cette thèse étaient de (i) déterminer la distribution des concentrations sériques de 25 hydroxy vitamine D [25 (OH) D] chez les personnes âgées en bonne santé, vivant au Québec et de déterminer comment la saison, l'âge, le sexe et la consommation de suppléments affectent cette distribution; (ii) de déterminer dans quelle mesure l'apport alimentaire de vitamine D, l'apport de suppléments et la saison peuvent expliquer les variations des concentrations sériques de 25 (OH) D, en contrôlant pour les effets de l'âge et du sexe, ainsi que de déterminer l'apport alimentaire idéal de vitamine D pour obtenir un niveau optimal de 25 (OH) D; et, finalement (iii) d'évaluer l'effet de l'état nutritionnel en vitamine D sur la diminution des capacités fonctionnelles pendant 1 et 2 ans, tout en prenant en compte la saison et d'autres variables de confusion potentielles. Cette étude repose sur des données obtenues auprès d'un échantillon aléatoire de 405 participants de l'étude de cohorte NuAge, composée de 1793 hommes et femmes âgés entre 68 et 82 ans au départ, vivant de façon indépendante. Cet échantillon est stratifié selon trois catégories d'âge: 70 ± 2 ans, 75 ± 2 ans et 80 ± 2 ans, avec des nombres comparables d'hommes et de femmes dans chaque gr
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Gallo, Sina. "An examination of parental compliance with vitamin D recommendations and the physiological responses to vitamin D isoform and dosage in breastfed infants from greater Montréal." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=116878.
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Vitamin D is important to maintain calcium homeostasis and promote healthy bone development. Breastfed newborns are at heightened risk of vitamin D deficiency because breast milk contains insufficient amounts of vitamin D. Canadian health policy recommends all breastfed infants receive 400 IU/d of vitamin D starting at birth and continuing until infants can obtain this amount through diet. Both dietary and endogenous production of vitamin D are commonly measured using the 25-hydroxyvitamin D metabolite (25(OH)D), as it has a longer half-life and is less hormonally regulated than the active form, 1,25-dihydroxyvitamin D. The Institute of Medicine (IOM) defines the amount necessary to meet the needs of 97.5% of a population group as the Recommended Dietary Allowance (RDA), however due to insufficient supportive data for the 0-12 mo age group an Adequate Intake (AI) level of 400 IU/d was established instead. This amount is thought to maintain circulating 25(OH)D concentrations in the range of 40-50 nmol/L, sufficient for bone health. Others argue concentrations >75 nmol/L are necessary and that some infants and children may require 800 IU/d of vitamin D supplementation. Despite these recommendations, many infants in Canada have low circulating 25(OH)D concentrations. It is unclear whether these low concentrations are due to a lack of compliance or that the recommendations are insufficient to achieve the desired circulating 25(OH)D concentrations. In addition, whether intakes of vitamin D >400 IU/d in infancy are associated with better bone mineral accrual has not been systematically tested. There are two isoforms of vitamin D which are available as supplements in Canada, cholecalciferol (vitamin D3) and ergocalciferol (vitamin D2). Controversy exists regarding the biological effectiveness of both forms to increase 25(OH)D concentrations. Health Canada's 2004 recommendation states vitamin D2 is less effective than D3 for supplementation, yet no studies have directly compared the efficacy these isoforms in infants. The global objectives of this thesis are to: (1) describe vitamin D supplementation practices of mothers of newborns from a large Canadian urban center; (2) compare the biological response to supplemental vitamin D2 and D3 isoforms in breastfed infants from 1 to 4 mo of life; and (3) define the dosage requirement of vitamin D3 based on (a) the amount necessary to raise plasma 25(OH)D to ≥75 nmol/L in 97.5% of infants (as used in setting the RDA) and (b) using measures of mineral homeostasis, growth and bone mass. Study 1 consisted of a telephone survey with 342 mothers who delivered at the Royal Victoria Hospital (Montréal, Québec), representing ~10% of all annual births at this center. Mothers were contacted 6-12 mo post-partum and asked about vitamin D supplementation practices including the amount and frequency of dosage as well as reasons for non-adherence. Study 2 was a randomized clinical trial (RCT) of 52 breastfed infants. At 1 mo of age, infants received 400 IU/d of either vitamin D2 or D3 for 3 mo. The change in plasma 25(OH)D concentrations as well as the proportion of infants which achieved ≥50 and ≥75 nmol/L plasma 25(OH)D targets were compared between groups. Study 3 was a RCT in which 132 healthy, breastfed 1 mo old infants were randomly assigned to receive one of 4 vitamin D dosages (400, 800, 1200 or 1600 IU/d of vitamin D3).La vitamine D est importante pour maintenir l'homéostasie du calcium et pour promouvoir le développement des os. Les nouveau-nés allaités ont un risque accru en carence de vitamine D car le lait maternel est insuffisant en vitamine D. Santé Canada recommande que tous les nourrissons allaités reçoivent 400 UI/jour de vitamine D dès la naissance et jusqu'à ce qu'ils puissent obtenir cette quantité par l'alimentation. La production alimentaire et endogène de la vitamine D est généralement mesurée en utilisant le métabolite 25-hydroxyvitamine D (25(OH)D) car il a une demi-vie plus longue et est moins contrôlé par les hormones que la forme active, soit la 1,25-dihydroxyvitamine D. L'Institute of Médicine (IOM) définit la quantité nécessaire pour répondre aux besoins de 97,5% d'une population avec l'apport nutritionnel recommandé (ANR), mais en raison de l'insuffisance des données scientifiques pour le groupe d'âge 0 à 12 mois, un apport suffisant de 400 UI/jour a été créé à la place. Cette quantité est jugée suffisante pour maintenir les concentrations plasmatique de 25(OH)D dans la gamme de 40-50 nmol/L, suffisante pour la santé des os. D'autres soutiennent que des concentrations >75 nmol/L sont nécessaires et peuvent nécessiter 800 UI/ jour de vitamine D pour certains nourrissons et enfants. Malgré ces recommandations, certains nourrissons au Canada ont des concentrations faibles de 25(OH)D. Il est difficile de savoir si ces faibles concentrations sont dues à un non suivi de la posologie ou parce que les recommandations sont insuffisant pout atteindre des niveau sanguins de 25(OH)D désirée. À ce jour, les résultats quant a savoir si les apports en vitamine D de >400 UI/jour pendant l'enfance ont des conséquences bénéfiques sur l'accumulation du contenu minéral osseux n'ont pas étés explorés scientifiquement. Il existe deux isoformes de la vitamine D qui sont disponibles sous forme de suppléments au Canada, soit cholécalciférol (vitamine D3) et ergocalciférol (vitamine D2). Il y a une controverse quant à l'efficacité biologique de ces deux formes ayant pour effet d'augmenter les niveaux sanguins de 25(OH)D. Santé Canada à stipulé dans sa recommandation de 2004, que la vitamine D2 est moins efficace que la D3 hors, aucune étude n'a comparé l'efficacité de ces isoformes directement chez les nourrissons. L'objectif global de cette thèse est de: (1) décrire les pratiques de suppléments de la vitamine D par la mère du nouveau-né, dans un grand centre urbain au Canada, (2) de comparer la réponse biologique à un supplément de vitamine D2 vs. D3 chez les nourrissons allaités de 1 à 4 mois de la vie, et (3) définir le dosage quotidien de la vitamine D3 en fonction de la quantité nécessaire pour (a) élever les niveaux plasmatique de 25(OH)D ≥75 nmol /L dans 97,5% des nourrissons (telle qu'était utilisée dans la détermination de l'ANR) et (b) utilisant des mesures de l'homéostasie minérale, de la croissance et du contenu de la masse osseuse. L'étude 1 a consisté d'une enquête téléphonique auprès de 342 mères ayant accouchées à l'hôpital Royal Victoria (Montréal, Québec), représentant environ 10% de toutes les naissances annuelles à Royal Victoria. Les mères ont étés contactées entre 6 à 12 mois post-partum, et questionnées sur les pratiques quant aux suppléments en vitamine D, en particulier sur la quantité et la fréquence des doses ainsi que les raisons du non-respect. L'étude 2 était un essai clinique aléatoire (ECR) de 52 nourrissons allaités d'un mois d'âge. Ces nourrissons ont reçu 400 UI/jour de vitamine D2 ou D3 pour une durée de 3 mois. Le changement dans les niveau plasmatique de 25(OH)D ainsi que la proportion de nourrissons qui ont atteint ≥50 et ≥75 nmol/L de 25(OH)D ont été comparés entre les deux groupes. L'étude 3 était un ECR dont 132 bébés allaités d'un mois d'âge, en bonne santé, ont étés assignés au hasard à recevoir l'une des 4 doses de vitamine D3 (400, 800, 1200 ou 1600 UI/jour).