Rozprawy doktorskie: „Vitamins in human nutrition”

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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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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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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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Syphard, James Eric. "Sports supplement database /". Link to this database on the INTERNET, 2003. http://sportsupplementdb.project.cisat.jmu.edu/.

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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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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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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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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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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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Made available in DSpace on 2016-01-13T13:28:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-02-23. Added 1 bitstream(s) on 2016-01-13T13:33:45Z : No. of bitstreams: 1 000855702.pdf: 1803642 bytes, checksum: dea7988d55fe2132d8ebc5a1236956ae (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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 Ribeiro
Coorientador: 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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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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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.

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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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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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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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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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18

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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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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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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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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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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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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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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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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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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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 Î¼g/.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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Kam, May-sin, i 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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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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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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33

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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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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Hashemi, Dana. "The role vitamins in human life". Thesis, Київський національний університет технологій та дизайну, 2019. https://er.knutd.edu.ua/handle/123456789/13181.

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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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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 F_2α 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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Gale, Catherine Rose. "Antioxidant vitamins, cerebrovascular disease and cognitive function in elderly people". Thesis, University of Southampton, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.264648.

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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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Santschi, Debora. "Fate of B-complex vitamins in the gastrointestinal tract of dairy cows". Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=81432.

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Three experiments were conducted to characterize the fate of B-vitamins in the gastrointestinal tract of dairy cows. Experiment 1 was undertaken to verify if differences among published studies could be explained by methods of collection and preparation of ruminal fluid, using four ruminally cannulated non-lactating Holstein cows. Acidification of fresh ruminal fluid, causing the lysis of bacterial cells, yielded higher B-vitamin concentrations than differential centrifugation, while the method of collection used did not have an important impact. Results suggested that most of the vitamins are present in the bacterial fractions, and that only limited amounts are present in the surrounding fluid. Experiment 2 looked at the vitamin concentrations in ruminal bacterial fractions and particle-free fluid as influenced by diet composition. Six lactating ruminally cannulated Holstein cows were used in a cross-over design, and the diets were formulated to have forage to concentrate ratios of 60:40 (high-forage) and 40:60 (low-forage). B-vitamins were present mainly in the bacterial fractions of the rumen, with greater effects of the forage to concentrate ratio on vitamin concentrations in the bacteria associated to the solid fraction than on those present in the liquid portion of the rumen. These results strongly suggested that ruminal B-vitamin synthesis is influenced by the forage to concentrate ratio. Experiment 3 investigated the fate of supplementary B-vitamins, using four cows equipped with cannulae in the rumen, the proximal duodenum and the distal ileum. Extensive losses of dietary supplements appeared prior to the duodenum for all vitamins, but intestinal disappearance rates of most vitamins were increased by supplementation.

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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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West, Virginia Anne. "Stability of Selected B Vitamins in Thermally-Treated Pinto Beans". BYU ScholarsArchive, 2015. https://scholarsarchive.byu.edu/etd/5769.

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Beans are a commonly consumed food and a staple in many regions worldwide. Pinto beans (Phaseolus vulgaris), categorized as legumes, are dried seeds from plants and are high in protein, carbohydrate and fiber, and low in fat. They are also a good source of various minerals and well as thiamin, riboflavin, niacin, vitamin B6, and folate Beans are typically soaked and thermally processed before consumption. Different processing methods can impact the composition of beans. The purpose of this study was to examine the effect of thermal treatments on vitamin concentration in pinto beans. Beans were simmered, canned, dried-flaked, or dried-extruded, and measured for thiamin, riboflavin, folate, and vitamin B6. Beans were then reheated and measured again for vitamin concentration. Vitamin loss was comparable between the most commonly consumed stages of processing: Simmered, canned reheated, dried-flaked reheated and dried-extruded reheated. The only statistically significant differences were that simmering caused the least amount of degradation of thiamin and dried-flaked product had the least amount of vitamin B6 degradation. Though dried-flaked and dried-extruded beans generally decreased in vitamin concentration, these two products were comparable to the simmered and canned reheated products. This suggests that drying is a nutritionally acceptable means of processing pinto beans, resulting in products that are more economical to transport and more convenient to prepare.

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GIORDANO, DEBORAH. "Transglutaminase, nutrition and human health". Doctoral thesis, Università degli Studi di Foggia, 2019. http://hdl.handle.net/11369/382619.

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Conoscenze preesistenti: Le transglutaminasi (TGase) sono una classe di enzimi ampiamente diffusa tra gli organismi procarioti ed eucarioti. Gli enzimi di questa famiglia catalizzano modifiche post-traduzionali in molte proteine attraverso reazioni di trasferimento dell’acile, reazioni di deaminazione e di crosslinking (polimerizzazione) tra residui peptidici di lisina (accettore di acile) e glutammina (donatore di acile) intra- o inter-catena proteica. A causa della sua facilità di espressione e di purificazione, l’unica TGase ampiamente usata per le applicazioni industriali è la TGase microbica estratta da Streptomyces mobaraensis (MTGase). Oggigiorno la MTGase è disponibile in commercio ed è ampiamente usata nell’industria dei biopolimeri, in cosmetica, per applicazioni cliniche, nell’industria tessile della lana e soprattutto nell’industria alimentare. La sua abilità di catalizzare legami crociati in molti substrati proteici differenti è sempre più usata non solo per la produzione di salsicce, prosciutti e formaggi ma, molto recentemente, anche per la detossificazione della farina, come possibile terapia alternativa alla dieta senza glutine. Ne consegue che oggigiorno le applicazioni industriali della MTGase stiano aumentando, coinvolgendo sempre più settori e producendo una ricerca scientifica su questo argomento sempre più fervente, allo scopo di tentare di rispondere a specifiche esigenze industriali, come l’implementazione di sistemi di purificazione della MTGase più efficienti, la ricerca di fonti alternative di transglutaminasi microbica, e di fonti sicure di enzimi ricombinanti. Scopo del progetto di dottorato: lo scopo principale del progetto è l’identificazione di nuove forme di transglutaminasi microbica che possano diventare un’alternativa a quella attualmente in uso. È stata eseguita un’analisi approfondita delle sequenze note allo scopo di ottenere una classificazione delle TGase microbiche attraverso la loro similarità a forme note. Per selezionare le migliori candidate che possano essere forme attive in appropriate condizioni, le sequenze selezionate sono state soggette di modellamento molecolare e simulazioni molecolari. Per testare l’attività enzimatica, sono stati effettuati dei saggi sperimentali su una nuova forma trovata ed un’ulteriore nuova forma è stata espressa. Risultati: il presente lavoro propone in primo luogo un’analisi, ad oggi assente, dell’ampio panorama delle transglutaminasi microbiche, sviluppando la prima classificazione delle TGase microbiche basata sulle loro caratteristiche di sequenza e sulle loro specifiche strutture secondarie predette. Al fine di classificare ed analizzare le caratteristiche strutturali di tutte le sequenze annotate come aventi un TGase core, sono state utilizzate tecniche computazionali che coinvolgono analisi di sequenza, studi comparativi, costruzione di alberi filogenetici, modellamento per omologia e simulazioni di dinamica molecolare. Tramite questo approccio, è stata effettuata una classificazione preliminare di queste sequenze dividendole in cinque gruppi principali. Ogni gruppo è stato studiato dal punto di vista delle sequenze per analizzare la presenza di motifs specifici. Per tre di questi cinque gruppi, sono state studiate anche le strutture secondarie e, da questa analisi, sono state rilevate caratteristiche specifiche per ogni gruppo. Inoltre, due nuove forme di TGase microbica (mTGase) sono state studiate in dettaglio: K. albida mTGase e l’ipotetica mTGase da SaNDy (organismo non rivelato per possibilità di brevetto). Per la prima, in comparazione con la MTGase, sono state effettuate analisi della tasca relativa al sito attivo e simulazioni di dinamica molecolare. Per la seconda, invece, sono state utilizzate tecniche sperimentali per purificare l’ipotetico enzima al fine di testarne l’attività su substrati alimentari. Saggi sperimentali su entrambe le proteine sono ancora in corso, al fine di trovare le migliori condizioni di attività enzimatica e i migliori substrati di reazione. Le simulazioni di dinamica molecolare eseguite sulla mTGase di K. albida hanno suggerito alcune spiegazioni alla maggiore specificità di questo enzima rispetto alla MTGase, dimostrata sperimentalmente da Steffan e colleghi, ed alcune indicazioni per variare le condizioni di attività usate per testarla. Inoltre, l’analisi dei substrati ha permesso di trovare nuovi possibili substrati, sui quali l’enzima potrebbe essere impiegato ai fini della riduzione delle allergenicità. D’altro canto, l’enzima estratto da SaNDy, mostrando una più alta somiglianza con la MTGase, potrebbe essere meno selettivo della mTGase da K. albida nei confronti di specifici substrati, pertanto potrebbe essere possibile una sua applicazione anche su substrati gliadinici, tuttavia, per provare ciò, sono necessari ulteriori esperimenti. Note: il presente lavoro di dottorato è stato principalmente svolto presso il Laboratorio di Bioinformatica del CNR di Avellino sotto la supervisione del Dr. Facchiano, tuttavia, tutte le simulazioni di dinamica molecolare sono state eseguite presso il Dipartimento di Biochimica dell’Università di Zurigo, nel laboratorio di biologia strutturale e computazionale sotto la supervisione del Prof. A. Caflisch e del suo gruppo di ricerca (periodo di formazione all’estero obbligatorio). I saggi di attività sperimentale sul substrato gliadinico sono stati effettuati dal laboratorio di spettrometria di massa CeSMA-ProBio presso il CNR di Avellino; e l’ipotetica mTGase da SaNDy è stata invece clonata, espressa e purificata durante la collaborazione con il laboratorio di Molecular Sensing presso il CNR of Avellino.
Background: transglutaminases (TGase) are a class of enzymes widely spread in eukaryotic and prokaryotic organisms. Enzymes of this family catalyze post-translational modifications in many proteins by acyl transfer reactions, deamidation and crosslinking (polymerisation) between protein intra- or inter-chain glutamine (acyl donor) and lysine (acyl acceptor) peptide residues. Due to its facility of expression and purification, the only TGase enzyme widely used for industrial applications is the microbial TGase extracted from Streptomyces mobaraensis (MTGase). Nowadays the MTGase is commercially available and widely used in biopolymers industry, in cosmetics, in clinical applications, in wool textiles, and above all in the food processing industry. Its ability to catalyze crosslinks on many different protein substrates is increasingly used not only for sausage, ham and cheese production but, very recently, also for flour detoxification, as a possible alternative therapy to the gluten free diet. It follows that nowadays the industrial applications of MTGase have increased, covering more and more fields producing a very active scientific research about this topic aimed at attempt to meet specific industrial needs, as the implementation of more efficient system for MTGase production, the research of alternative sources of microbial TGase, and safe source of recombinant enzymes. Aims of the doctorate project: the main aim of the project is the identification of novel forms of microbial TGases that could become an alternative to that in use. A depth screening of known sequences has been performed, with the aim of obtaining a classification of microbial TGases for their similarity to known forms. To select the best candidates to be active forms under appropriate conditions, molecular modelling and molecular simulations have been performed on selected sequences. To test the enzymatic activity, experimental assays have been performed with a novel form, and another novel form has been expressed. Results: the present work proposes at first an analysis, lacking so far, of the wide microbial transglutaminase world, developing the first classification of the microbial TGase based on their sequence features and their specific predicted secondary structures. In order to classify and analyze the structural features of all the sequences annotated as having a TGase core computational techniques involving sequence analyses, comparative studies, building of phylogenetic trees, homology models and molecular dynamic simulations have been used. From this approach, a preliminary classification of these sequences was done by dividing them in five main groups. Each group has been investigated from the sequence point of view to analyze the presence of specific motifs. For three of this five groups, also the secondary structures have been investigated and, from this analysis, features specific for each group have been detected. Moreover, two novel forms of microbial TGase (mTGase) have been investigated in the detail: K. albida mTGase and the hypothetical mTGase from SaNDy (organism not disclosed for patent opportunity). Molecular dynamics simulations and active site pocket analyses have been performed for the first, in comparison with MTGase. For the second, instead, experimental technique has been used to purify the hypothetical enzyme in order to test it on food related substrates. Experimental assays on both the proteins are still ongoing, to find the best enzymatic activity conditions and the best substrates of reaction. The molecular dynamic simulations performed on K. albida mTGase have suggested some explanations to the higher specificity of this enzyme than MTGase, experimentally demonstrated by Steffen et colleague, and several indications to change the activity conditions used to test it. Moreover, the substrates screening has allowed to find novel possible substrates, on which this enzyme could be employed for the allergenicity reduction. On the other hand, the enzyme extracted from SaNDy, showing a higher similarity with MTGase, could be less selective than K. albida mTGase for specific substrates, so it could be possible its application also on the gliadin substrate, but to prove it further experiments are necessary. Note: the present PhD work has been mainly performed in the Bioinformatics Laboratory at the CNR of Avellino under Dr. Facchiano’s supervision, however all the MD simulations have been performed at the Biochemistry Department of the University of Zurich, in the computational and structural biology laboratory under the supervision of Prof. A. Caflisch and his research group (compulsory abroad training period). Experimental activity assays on gliadin substrate have been performed by the spectrometry mass CeSMA-ProBio lab at the CNR of Avellino; and the hypothetical mTGase from SaNDy was instead cloned, expressed and purified in collaboration with the Laboratory for Molecular Sensing at the CNR of Avellino.

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Agustiana, Agatha. "The dose-response effects of the amount of oil in salad dressing on the bioavailability of carotenoids and fat-soluble vitamins in salad vegetables". Thesis, Iowa State University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=1596916.

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The objectives of the study were to define the dose-response relation of the amount of added oil and: 1) the absorption of carotenoids, phylloquinone and tocopherols in salad vegetables and 2) the absorption of retinyl palmitate formed from the ingested provitamin A carotenoids, |A- and |A-carotene. Women (n = 12) each consumed 5 salads containing equivalent amounts of carrot, cherry tomato, romaine lettuce and spinach. The salads with salad dressings containing 0, 2, 4, 8 or 32 g tocopherol-stripped soybean oil were ingested in random order separated by !Y 2 weeks. Blood samples were collected at baseline and 2, 3.5, 5, 7, and 9.5 h postprandially. Chylomicron fractions were extracted and analyzed by HPLC with coulometric array electrochemical detection. When the salads were ingested with 0 g oil, there was negligible absorption of |A- and |A-carotenes, lutein, lycopene, phylloquinone, retinyl palmitate, |A- and |?-tocopherols. For |A- and |A-carotenes, lycopene, retinyl palmitate, and |A- and |?-tocopherols, absorption was increased with each amount of oil compared with 0 g oil (P <0.05). Starting from 4 g oil, all analytes (|A-carotene, |A-carotene, lutein, trans-lycopene, vitamin A, |A-tocopherol, |?-tocopherol, and vitamin K1) showed significant increases in absorption compared with 0 g oil salad dressing. The absorption of each carotenoid and fat-soluble vitamin was highest with 32 g ingested oil (P < 0.002).

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REIS, ROGERIO A. de S. "Caracterização de componentes inorgânicos em suplementos nutricionais pelo método de análise por ativação com nêutrons". reponame:Repositório Institucional do IPEN, 2006. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11401.

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Made available in DSpace on 2014-10-09T12:51:31Z (GMT). No. of bitstreams: 0
Made available in DSpace on 2014-10-09T14:02:00Z (GMT). No. of bitstreams: 0
Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP

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Sullivan, Allison. "Dietary Nutrient Intake and Cytokines in Children with Asthma and Allergic Disease". University of Cincinnati / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1573810939821528.

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Roberts, Kristen M. "Dietary Bioactives and Human Prostate Carcinogenesis". The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429195549.

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Meglia, Guillermo Esteban. "Nutrition and immune response in periparturient dairy cows : with emphasis on micronutrients /". Uppsala : Dept. of Obstetric and Gynaecology, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/v170.pdf.

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Weeden, Allisha Marie. "Associations among dietary supplement use, dietary intake, and chronic health conditions of older adults". Diss., Manhattan, Kan. : Kansas State University, 2008. http://hdl.handle.net/2097/893.

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Nelson, Chailyn. "Dietary Folate, Other B-Vitamins and Incident Alzheimer's Disease: The Cache County Memory, Health, and Aging Study". DigitalCommons@USU, 2008. https://digitalcommons.usu.edu/etd/110.

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This study involves data from the Cache County Study, which began in 1994 with joined efforts by Duke University, Utah State University, and Johns Hopkins University. It consisted of 5,092 participants from Cache County, Utah, located in the northern part of the state. Characteristics of the population include high participation rates (~ 90%), a majority of participants are members of The Church of Jesus Christ of Latter-day Saints, longer life expectancy than the general US population, a greater than 80% rate of at least a high school education, and low rates of migration. Subjects cognitive status was screened using the Modified Mini-Mental State Examination or rated by knowledgeable informants using an Informant Questionnaire for Cognitive Decline. Low scoring subjects were examined using the Dementia Questionnaire, an inventory of cognitive symptoms, functional impairments, and medical conditions relevant to dementia. The clinical data were reviewed by a geropsychiatrist and neuropsychologist. Those suspected of dementia underwent further testing and final dementia diagnoses were decided by a consensus conference of experts. Clinical assessment at the baseline interview identified 368 individuals out of the original 5,092 subjects as having dementia. These individuals were removed from the present analysis. Prevalent cases of dementia were excluded in our analyses of risk associated with incident AD. Dietary data were collected using a food frequency questionnaire at baseline in 1995. A list of 142 foods was provided and participants noted frequency they consume the food or food group. To calculate intake of a specific nutrient, the nutrient content of each food is multiplied by the frequency of consumption for each food. This number is summed over all food items. Cox Proportional hazards modeling was used to assess risk of incident AD in relationship to folate and B-vitamin intake over eleven subsequent years of data collection. Cox modeling assists in analysis of censored cases (drop-outs and deaths). No relationship was found between folate from food, supplement, or combined sources with dementia or with AD. Similar results were observed for B-12 and B-6.

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