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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
181

Embryogenesis is dependent upon 12-lipoxygenase, 5-lipoxygenase, and α-tocopherol to modulate polyunsaturated fatty acid status and the production of oxidized fatty acids in zebrafish / Embryogenesis is dependent upon 12-lipoxygenase, 5-lipoxygenase, and alpha-tocopherol to modulate polyunsaturated fatty acid status and the production of oxidized fatty acids in zebrafish

Lebold, Katherine M. 25 May 2012 (has links)
Arachidonic acid (ARA) and docosahexaenoic acid (DHA) are polyunsaturated fatty acids required for proper embryonic development, specifically neurodevelopment. However, little is known regarding their conversion to other metabolites during embryogenesis. The oxidation of ARA gives rise to the biologically active eicosanoids and the oxidation of DHA gives rise to the biologically active docosanoids. The oxidation of ARA and DHA occurs through enzymatic processes, via lipoxygenase (LOX), or non-enzymatic processes, via radical-mediated lipid peroxidation. We hypothesize that oxidation of ARA and DHA via LOX is required for proper embryonic development. Additionally, we hypothesize that α-tocopherol, a potent lipid soluble antioxidant, mediates the conversion of ARA and DHA to their respective oxidized metabolites. Using zebrafish as a model of vertebrate embryogenesis, we found that the selective knockdown of either 12-LOX or 5-LOX decreased the production of docosanoids, altered fatty acid homeostasis, and increased the incidence of malformations and mortality in embryos by 24 hours post fertilization. α-Tocopherol deficiency also increased the incidence of malformations and mortality during embryogenesis, and in its absence, increased oxidized metabolites of ARA and DHA and decreased fatty acids concentrations. Therefore, oxidized metabolites of ARA and DHA perform crucial functions during embryonic development, but the production of oxidized fatty acids must be balanced with antioxidant bioavailability for proper embryogenesis. / Graduation date: 2012
182

Cobalamin communication in Sweden 1990 – 2000 : views, knowledge and practice among Swedish physicians

Nilsson, Mats January 2005 (has links)
Cobalamin (vitamin B12) is one of several essential micronutrients needed by the human organism. Other important micronutritients, which interplay with vitamin B12, are folate and iron. During the last ten years, the attention has been drawn to different forms of neurological disorders supposed to be caused by vitamin B12 deficiency. Vitamin B12 deficiency states are common among elderly patients in primary health care and sometimes in hospital care, especially in geriatric practice. This is a study to define the cobalamin treatment traditions, among Swedish physicians in the period 1990 – 2000. The period was distinguished by an intense debate on the issue by the physicians, an increase of cobalamin consumption, and a shift from parenteral therapy towards oral high-dose therapy. It had been known that symptoms of cobalamin deficiency could start in the nervous system. This knowledge was reinforced by the application of homocysteine and methyl-malonic acid (MMA) in deficiency diagnosis. Introduction of homocysteine and MMA in deficiency diagnosis changed the view on deficiency prevalence, by identifying persons at risk to develop B12 deficiency prior to established symptoms. In this study, Swedish physicians are regarded mainly as receivers of communication about the markers homocysteine and MMA, and deficiency states of cobalamin and folate. The main senders were scientists from North America, Norway, Denmark, and Sweden. This study sets the senders and the receivers of cobalamin communication on a collegial level and quantifies and evaluates the feed-back from the receivers. The receivers, gen¬eral practitioners and geriatricians, appeared to be familiar with old knowledge and frontier concepts in the field. Thus, it is suggested that the increase of B12 prescriptions in Sweden 1990 – 2000 reflected an increased awareness of B12-associated clinical problems among the physicians managing the majority of deficiency patients, although a possible overconsumption of pharmaceutical drugs must be kept in mind.
183

Nutritional quality and consumer acceptability of provitamin A-biofortified maize.

Pillay, Kirthee. January 2011 (has links)
Vitamin A deficiency (VAD) is a major public health problem in developing countries, including South Africa. The potential of provitamin A-biofortified maize for use as a complementary strategy to alleviate vitamin A deficiency in developing countries, where maize is the dominant staple food, is currently a subject of research. Although the nutritional composition of white maize is thought to be similar to that of biofortified maize, apart from the differences in provitamin A carotenoid content, the comparative nutritional composition of the two maize types seems not to have been subjected to a comprehensive scientific study. When setting the target level of provitamin A in the provitamin A-biofortified maize, it is important to consider the potential effect of processing on the final provitamin A carotenoid content of the biofortified food products, as the provitamin A carotenoids levels may decrease on processing. Furthermore, the yellow/orange provitamin A-biofortified maize may not be widely accepted by African consumers who are vulnerable to VAD, and are traditional consumers of white maize. This study firstly aimed to evaluate the nutritional composition, including provitamin A composition, and grain quality of provitamin A-biofortified maize varieties, compared to white maize. The second aim was to assess the effect of processing (milling and cooking) on the retention of provitamin A carotenoids and other nutrients in popular South African maize food products prepared with provitamin A-biofortified maize. Thirdly, the study aimed to assess the acceptability of maize food products prepared with provitamin A-biofortified maize by consumers of different age and gender in rural KwaZulu-Natal, South Africa. The grains of the provitamin A-biofortified maize varieties and grain of a white maize variety (control) were analysed for their nutritional composition using standard or referenced methods. The carotenoid content of the grains was analysed by High-Performance Liquid Chromatography (HPLC) and mass spectroscopy. The provitamin A carotenoids β-cryptoxanthin, and trans and cis isomers of β-carotene, and other unidentified cis isomers of β-carotene were detected in varying levels in the provitamin A-biofortified maize varieties. The total provitamin A content in the biofortified maize varieties ranged from 7.3-8.3 μg/g dry weight (DW), with total β-carotene ranging from 3.5-3.6 μg/g DW, and β-cryptoxanthin from 3.7-4.8 μg/g DW, whilst no carotenoids were detected in the white maize variety. Results of the evaluation of the content of other nutrients showed that, when compared with the white maize variety, the provitamin A-biofortified maize varieties had higher levels of starch, fat and protein but were lower in iron. The zinc and phosphorus levels in the white maize and the biofortified maize were comparable. The biofortified maize varieties were better sources of most of the essential amino acids relative to the white maize, but, similar to the white maize, they were deficient in histidine and lysine, indicating that further improvement is required. Selected quality attributes (grain density, susceptibility of kernels to cracking, milling quality and resistance of the kernels to fungal infection) of grains of 32 provitamin A-biofortified maize varieties and a white variety (control) were assessed. Overall, the quality of the grains of the provitamin A-biofortified maize varieties were found to be superior to that of the white maize grain, although the biofortified maize grains showed less resistance to fungi, including mycotoxin-producing types. This indicates that the trait of grain resistance to infection by fungi should also be incorporated in the provitamin A-biofortified maize varieties during breeding. To assess the retention of provitamin A carotenoids and other nutrients in maize food products, three selected provitamin A-biofortified maize varieties and the control (white maize variety) were milled into mealie meal and samp. The milled products were cooked into three products: phutu and thin porridge (from the mealie meal) and cooked samp. Nutrient retention during processing was determined. Milling resulted in either an increase or slight decrease in the provitamin A carotenoid levels, but there was no major decrease in the total provitamin A level. Most of the other nutrients were well retained during milling, but there were substantial losses of fibre, fat and minerals. Provitamin A carotenoid levels decreased on cooking. In phutu 96.6 ± 20.3% β-cryptoxanthin and 95.5 ± 13.6% of the β-carotene was retained after cooking. In thin porridge 65.8 ± 4.6% β-cryptoxanthin and 74.7 ± 3.0% β-carotene; and in samp 91.9 ± 12.0% β-cryptoxanthin and 100.1 ± 8.8% of the β-carotene was retained after cooking, respectively. Provitamin A retention seemed to be influenced by both maize variety and food form, indicating that suitable varieties and food forms should be found. There was generally a high retention of the other nutrients in all the three cooked products, except for the substantial losses of fat in thin porridge and iron and phosphorus in cooked samp. These findings indicate that an optimal delivery of provitamin A to the consumer can be achieved by processing provitamin A-biofortified maize into foods that have a good retention of provitamin A carotenoids, such as phutu and samp. These food products would be recommended in areas where VAD is prevalent. In order to assess consumer acceptability of provitamin A-biofortified maize, a total of 212 subjects aged 3-55 years from Mkhambathini Municipality, in KwaZulu-Natal province, South Africa, participated in the sensory evaluation of phutu, thin porridge and cooked samp prepared with provitamin A-biofortified maize varieties and a white variety (control). Preference for yellow maize food products was negatively associated with an increase in the age of the subjects. Overall, preschool children preferred yellow maize to white maize food products: phutu (81% vs. 19%), thin porridge (75% vs. 25%) and samp (73% vs. 27%). In contrast, primary school children preferred white maize to yellow maize food products: phutu (55% vs. 45%), thin porridge (63% vs. 38%) and samp (52% vs. 48%). Similarly, secondary school children and adults also displayed a similar preference for white maize food products. There was no association between gender and preference for maize variety. Focus group discussions revealed that participants had a negative attitude towards biofortified maize due to its colour, taste, smell and texture. However, the participants expressed a willingness to consume biofortified maize if it was cheaper than white maize and was readily available in local grocery stores. These findings indicate that there is a potential to promote the consumption of provitamin A-biofortified maize and its food products in this part of South Africa, thereby contributing to a reduction in the incidence of VAD. This study has shown that provitamin A-biofortified maize has a good potential to be used as an additional strategy to alleviate VAD in poor communities of South Africa, including similar environments in sub-Saharan Africa. However, the study has revealed that there are still challenges to be overcome in order to achieve the target provitamin A content of 15 μg/g in provitamin A-biofortified maize, set by HarvestPlus, an international challenge program. This may also explain why provitamin A-biofortified maize varieties with this level of provitamin A have been scarcely reported in the literature. Thus, more research is required to achieve the target provitamin A level in maize by conventional breeding. The results of this study indicate that besides provitamin A, the biofortified maize is also a good source of other nutrients including starch, fat, protein and zinc. However, improving the consumer acceptability of the provitamin A-biofortified maize remains a challenge, due to the negative attitudes towards the yellow/orange maize by African consumers. On the other hand, the results of this study indicate that there is an opportunity to promote the consumption of provitamin A-biofortified maize food products by preschool children, a finding which has not been previously reported in the literature. Nutrition education on the benefits of provitamin A-biofortified maize, as well as improved marketing are recommended, in this part of South Africa and also in similar environments in other sub-Saharan countries. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
184

Association between vitamin A status and lung function in children aged 6-9 years in northern Ethiopia

Kassaye, Tarik. January 2000 (has links)
The overall aim of the research described in this thesis was to evaluate the effect of vitamin A supplementation on respiratory health, assessed by lung function in children aged 6--9 years. It comprises three studies. / The first study determined the magnitude of vitamin A deficiency in the target population in Wukro wereda, Northern Ethiopia. Of the 1339 eligible children identified by house to house surveys, 824 had complete data for vitamin A indicators and anthropometry. Xerophthalmia was detected in 5.8% of the children, 8.4% had serum retinol levels <0.35 mumol/L and 51.1% between 0.35--0.70 mumol/L. Liver vitamin A reserve was also found to be low in 41.0% of the children using the Modified Relative Dose Response (MRDR) and in about 85% of the children, the daily vitamin A intake was below the FAO/WHO basal requirement (<250 RE/day). / The second study found that in comparison with children with adequate vitamin A reserve (MRDR < 0.06), those with low reserve (MRDR &ge; 0.06) had forced expiratory volume in one second (FEV1) 48.8 ml (p = 0.006) lower when unadjusted, 23.1 ml (p = 0.04) when partially adjusted for age, gender and height and 14.1 ml (p = 0.20) when fully adjusted for demographic, general health, lung function and household related characteristics. / The third study describes the results of a randomized controlled trial (RCT) to evaluate the impact of vitamin A supplementation on respiratory health as assessed by change in FEV1 at 4 months. The average change was 53.3 ml (n = 496) and 53.8 ml (n = 501) in the vitamin A and placebo groups respectively. After adjusting for baseline covariates, the difference between them was -3.6 ml (95%CI: -21.6, 14.4). In sub-analysis of the data, gender and vitamin A status subcategories were found to be effect modifiers. / In conclusion, high dose vitamin A supplementation did not show an effect on change in FEV1 at 4 months in children aged 6--9 years with high prevalence of vitamin A deficiency. Sub-analysis findings suggest that the benefits to vitamin A intervention in the study setting can probably be achieved if the other nutritional deficiencies such as zinc are addressed. Moreover, the results also suggest that the effects of vitamin A supplementation on respiratory health status are complex and these need to be taken into account in future studies to assess the clinical and public health implications of vitamin A supplementation in this age group.
185

Vitamin A intake and antiviral properties of dietary traditional medicines among Kenyan Maasai children

Parker, Megan Elizabeth January 2004 (has links)
The Maasai of East Africa traditionally consume a diet of milk, meat, and blood. Previous studies have found the Maasai to suffer from vitamin A deficiency (VAD). This micronutrient deficiency compromises systemic immunity and increases morbidity and mortality. A semi-quantitative food frequency questionnaire (FFQ) was used to investigate the vitamin A intake of small Maasai children in Loita, Kenya. On average, children consumed 596mug/dayRAE from retinoid sources and 956mug/dayRAE when coupled with beta-carotene sources. The measles virus (MV) has yet to be eradicated from East Africa and remains a threat to young children. The Maasai have developed methods to deal with this disease and improve systemic immunity by introducing medicinal plants into the diet. Plant species added to the milk and soups of small children were determined using the FFQ. Antiviral properties of the seven most common dietary plants were then investigated, measuring MV neutralization and MV production, and compared to 7 arbitrarily selected non-medicinal plants. Significant differences (X2 p < 0.05) were found between the antiviral actions of medicinal and non-medicinal species.
186

Nutritional composition and acceptance of a complimentary food made with provitamin A-biofortified maize.

Govender, Laurencia. 13 May 2014 (has links)
Introduction: Micronutrient malnutrition has been identified as a serious health problem globally and is on the rise in South Africa. This is evident from the escalating burden of vitamin A deficiency (VAD) in South Africa. Rural infants are the most affected, as their diets often lack micronutrients. Food fortification, vitamin A supplementation and dietary diversity are the strategies that have been employed in South Africa to alleviate VAD. However, these strategies have not been effective, for various reasons. Biofortification is the production of micronutrient dense staple crops to alleviate micronutrient deficiencies. This strategy could complement existing strategies in the alleviation of VAD in South Africa and in other countries, especially in sub-Saharan Africa (SSA), where VAD is prevalent. Aim: The aim of this study was to investigate the nutritional composition and acceptance of a complementary food (soft porridge) made with provitamin A-biofortified maize by female infant caregivers from the rural areas of Umgungundlovu District of KwaZulu-Natal, South Africa. Objectives: (i) To evaluate the nutritional composition of soft porridge made with provitamin A-biofortified maize compared to non-biofortified white maize porridge; (ii) To assess the sensory acceptability of soft porridge made with the biofortified maize by black African female infant caregivers of varying age; and (iii) To determine the perceptions of the black African infant caregivers about the biofortified maize relative to the non-biofortified white maize. Methods: A cross-sectional study was conducted. Grains of two provitamin A-biofortified maize varieties and one white variety (control) were used. Grain and soft porridge of each variety of maize were analysed for their nutritional composition. The sensory acceptability of the porridges were evaluated by black African female infant caregivers, using a five-point facial hedonic scale. Focus group discussions were conducted, using some of the study subjects, to determine their perceptions about the provitamin A-biofortified maize. Results: The results showed that the grains of the provitamin A-biofortified maize varieties and their soft porridges were more nutritious than the control white variety in terms of energy, fibre, fat, protein, iron, zinc and phosphorus content. The results of the sensory evaluation indicated that there was no significant difference in the sensory acceptability of the biofortified soft porridges and the white maize soft porridge, irrespective of the age of the sensory evaluation panellists. The female caregivers perceived the biofortified maize as nutritious and health-beneficial and thought that infants would like its unique yellow colour and taste. However, the black African female caregivers perceived the provitamin A-biofortified maize as an animal feed or food for the poor. Nevertheless, the female caregivers expressed a willingness to give their infants porridge made with provitamin A-biofortified maize if it was cheap, readily available and health-beneficial. Conclusion: This study suggests that provitamin A-biofortified maize has the potential to be used as a complementary food item. Biofortification of maize with provitamin A could be used as a possible complementary strategy to assist in the alleviation of VAD in SSA. Furthermore, the relatively higher energy, fibre, fat, protein, iron, zinc and phosphorus content of the biofortified maize could contribute to the alleviation of protein-energy malnutrition and mineral deficiencies, respectively, which are prevalent in children of SSA. Although the findings of this study, like other previous studies, indicate that there are some negative perceptions about the provitamin A-biofortified maize, this study shows that provitamin A-biofortified maize soft porridge is as acceptable as white maize soft porridge to female infant caregivers from the rural areas of Umgungundlovu District of KwaZulu-Natal, South Africa. The female caregivers are thus likely to accept the biofortified maize for use as an infant complementary food in the form of soft porridge. Further research is recommended to expand the study area and consumer sample size in order to increase the confidence of inferring these results for large rural populations. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.
187

Aspects on clinical diagnosis of dementia, with focus on biological markers / Katarina Nägga.

Nägga, Katarina, January 2004 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 4 uppsatser.
188

Níveis séricos de vitamina D e câncer de mama no climatério: um estudo caso-controle

Souza e Silva, Melissa Quirino January 2012 (has links)
Submitted by Luis Guilherme Macena (guilhermelg2004@gmail.com) on 2013-04-08T12:33:46Z No. of bitstreams: 1 Melissa_Dissertação.pdf: 389612 bytes, checksum: ab23a920bbb76b9e01c6b056791e7adb (MD5) / Made available in DSpace on 2013-04-08T12:33:46Z (GMT). No. of bitstreams: 1 Melissa_Dissertação.pdf: 389612 bytes, checksum: ab23a920bbb76b9e01c6b056791e7adb (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto Fernandes Figueira. Departamento de Ensino. Programa de Pós-Graduação em Saúde da Criança e da Mulher. Rio de Janeiro, RJ, Brasil / Objetivo: avaliar a associação entre os níveis séricos de 25-hidroxivitamina D (25 OHD) e câncer de mama no climatério. Métodos: trata-se de um estudo do tipo casocontrole com mulheres de 45 a 70 anos atendidas nos ambulatórios de mastologia e ginecologia geral do hospital materno-infantil Instituto Fernandes Figueira, localizado no município do Rio de Janeiro. Foram selecionados 39 casos incidentes de câncer de mama e 60 controles. As participantes foram submetidas à entrevista para o preenchimento de um questionário estruturado e em seguida foi realizado a coleta de sangue para a dosagem de 25 OHD. Resultados: foi observada uma prevalência de 80,8% de hipovitaminose D (< 30ng/mL) entre as participantes do estudo. Em relação à estimativa de risco para carcinoma mamário, o grupo com níveis suficientes de 25 OHD não apresentou diferença com significância estatística do grupo com hipovitaminose D. Porém, na análise das estimativas de risco conforme o status menopausal, houve menor chance de exposição e desenvolvimento de câncer de mama nas mulheres pósmenopausadas com níveis suficientes de 25 OHD (OR* 0.53; IC 95%, 0.12-2.41) que as na pré-menopausa com níveis normais de vitamina D (OR* 0.97; IC 95%, 0.13-8.35) quando comparadas ao grupo com hipovitaminose D. Conclusão: Os resultados desse estudo sugerem que a hipovitaminose D entre mulheres pós-menopausadas seja um fator de risco para o câncer de mama durante o climatério. Todavia, ainda são necessários mais estudos que também confirmem essa associação. / Purpose: to evaluate the association between the plasma levels of 25-hydroxyvitamin D and the breast cancer in the climacteric. Methods: it is a kind of case-control study with women between 45 until 70 years old attended in clinics of mastology and ginecology of the maternal-infantile hospital Fernandes Figueira, localized in Rio de Janeiro city. Thirdy-nine incident cases of breast cancer and 60 controls were selected. The participants were submitted to an interview for filling out of a structured questionnaire and forthwith it was made the swab blood for the dosage of 25 OHD. Results: a prevalence of 80,8% of vitamin D deficiency was spotted among the participants of the study. In relation to the estimate of risk for breast cancer, the group with sufficient levels of 25 OHD did not present difference with significance statistic of the group with vitamin D deficiency. Nevertheless, during the analysis of the estimate of risk according to menopausal status, there were less chance of exposition and development of the breast cancer in postmenopaused women with sufficient levels of 25 OHD (OR* 0.53; IC 95%, 0.12-2.41) than the premenopaused women with normal levels of vitamin D (OR* 0.97; IC 95%, 0.13-8.35) when compared to the group with vitamin D deficiency. Conclusion: the results of this study suggests that the vitamin D deficiency among postmenopaused women is a factor of risk for the breast cancer during the climacteric. However, more studies are still necessary to confirm this association.
189

Influência da radiação ultravioleta nas diferentes estações do ano sobre os níveis séricos de 25-hidroxivitamina D em uma população de policiais militares da cidade de Porto Alegre - Brasil

Fontanive, Tiago Oselame January 2017 (has links)
Base teórica A deficiência da Vitamina D é um problema mundial, e têm sido associada com inúmeras doenças. Este hormônio pode ser obtido através da alimentação e através da produção na pele pela exposição à radiação ultravioleta B (R-UVB), sendo que a principal fonte é a exposição aos R-UVB. Objetivo Nossos objetivos foram avaliar a prevalência de deficiência da vitamina D de acordo com a estação do ano e seus fatores associados em adultos jovens e saudáveis, na cidade de Porto Alegre, RS, Brasil. Métodos Policiais militares de Porto Alegre, foram convidados a participar do estudo, amostras de sangue foram coletadas no primeiro dia de cada estação, refletindo desta forma a estação que antecedeu a coleta, para dosagem de 25(OH)D3, e PTH plasmáticos, cálcio total, creatinina e albumina no soro foram determinadas no outono. A UV-R foi mensurada a partir da radiação solar por meio de um radiômetro, calculando-se as doses diárias para eritema (D-Ery) e para resposta fotobiológica para síntese da vitamina D na pele humana (D-VitD). Resultados Nossos resultados mostraram uma variação sazonal de 25(OH)D3 (P = 0.000) nos indivíduos estudados, sendo fortemente influenciada pela média da R-UV nos 30 e 45 dias que antecederam as coletas, demonstrando o importante papel da R-UV na produção da vitamina D. A prevalência de 25(OH)D3 abaixo de 20ng/mL variou com as estações (p=0.000), tendo sido nula ou baixa no final do verão e primavera, no entanto, essa prevalência aumentou no final do outono (22%) e inverno (8.7%). Já 6 a prevalência de 25(OH)D3 < 30ng/mL foi alta em todas as estações do ano: inverno (70%), primavera (68%), verão (44%) e especialmente no outono(88%). O único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de UV-R no período que antecedeu a coleta. Conclusão A prevalência de deficiência de vitamina variou de acordo com a estação, em adultos jovens do sexo masculino, na região sul do Brasil, e o único fator associado de modo independente aos níveis de 25(OH)D3 foi a quantidade de R-UV no período que antecedeu a coleta. Palavras chave: Vitamina D, Deficiência de Vitamina D, Radiação ultravioleta, Radiação ultravioleta B. / Background Vitamin D deficiency is a worldwide problem, and has been associated with various diseases. This steroid can be obtained by food intake or by skin production, when exposed to UVB-R. Objective Our aims were to evaluate the prevalence of vitamin D deficiency according to the season and its associated factors in young adults, in Porto Alegre, RS, Brazil. Methods Young men were invited to participate, blood samples were collected on the first day of each season for 25(OH)D3 measurement, and PTH (parathyroid hormone) in plasma, total calcium, creatinine, and albumin in serum were determined in the autumn. UV-R was measured from solar radiation by means of a radiometer, calculating daily doses for erythema (D-Ery) and for photobiological response to vitamin D synthesis in human skin (D-VitD). Results Our results have shown a seasonal variation of 25(OH) D3(P=0.000) in young and healthy men, living in a semitropical region, who were strongly influenced by the mean UV-R in the 30 and 45 days previous, demonstrating the important role of UVR- induced skin production of vitamin D. The prevalence of 25(OH)D3 below 20ng/mL varied with the seasons (p=0.000), having been nil or low in late summer and spring. However, this prevalence increased in late autumn (22%) and winter (8.7%). The prevalence of 25(OH)D3<30ng/mL was high in all seasons of the year: winter (70%), spring (68%), summer (44%) and especially in autumn (88%). Conclusions 8 The prevalence of vitamin deficiency varied according to the season, in young and healthy male adults, in Southern Brazil, and the only factor independently associated with 25(OH)D3 levels was the amount of UV-R in the period prior to collection.
190

Avalia??o da suplementa??o com vitamina E, na forma natural ou sint?tica, em mulheres no p?s-parto imediato e sua concentra??o no colostro

Clemente, Heleni Aires 10 June 2013 (has links)
Made available in DSpace on 2014-12-17T14:03:42Z (GMT). No. of bitstreams: 1 HeleniAC_DISSERT.pdf: 2512013 bytes, checksum: e69e375e25ebb38b43385a02d5ecc6c7 (MD5) Previous issue date: 2013-06-10 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The Vitamin E consists of eight chemically homologous forms, designated alpha, beta, gamma and delta tocopherols and tocotrienols. Biologically, the alpha-tocopherol (&#945;-TOH) is the most important. Commercially, are found two types of &#945;-TOH a natural (RRR-alpha-tocopherol) and another synthetic (all-rac-alpha-tocopherol). Both forms are absorbed in the intestine, the liver is a preference in favor of forms 2R, due to transfer protein &#945;-TOH. It has higher affinity to these stereoisomers. Newborns are considered high risk for vitamin E deficiency, mainly premature, these have breast milk as a food source for maintenance of serum &#945;-TOH. Clinical signs such as thrombocytosis, hemolytic anemia, retrolental fibroplasia, intraventricular hemorrhage, bronchopulmonary dysplasia and spinocerebellar degeneration can be found in case of a low intake of &#945;-TOH. Thus, maternal supplementation on postpartum with &#945;-TOH can be an efficient way to increase levels of vitamin E in breast milk and thus the consequently increase the supply of micronutrient for the newborn. However, most studies with vitamin E supplementation have been conducted in animals and little is known about the effect of maternal supplementation in humans, as well as on its efficiency to increase levels of &#945;-TOH in human milk, depending on the shape natural or synthetic. The study included 109 women, divided into three groups: control without supplementation (GC) (n=36), supplemented with natural capsule (GNAT) (n=40) and the synthetic capsule (GSINT) (n=33). Blood samples were collected for determination of maternal nutritional status, and colostrums at initial contact and after 24 hours post-supplementation. Analyses were performed by High Performance Liquid Chromatography. Values of &#945;-TOH in serum below 499.6mg/dL were considered deficient. We used the Kruskal-Wallis test and Tukey test to confirm the increase of alpha-tocopherol in milk and efficiency of administered capsules. Daily consumption of &#945;-TOH was based on daily intake of 500 mL of colostrum by the newborn and compared with the nutritional requirement for children from 0 to 6 months of age, 4 mg / day. The mothers had mean concentration of serum &#945;-TOH in 1016 ? 52, 1236 ? 51 and 1083 ? 61 mg / dL, in CG, GNAT and GSINT respectively. There were no women with deficiiency. The GC did not change the concentrations of &#945;-TOH in colostrum. While women supplemented with natural and synthetic forms increased concentrations of &#945;-TOH colostrum in 57.6% and 39%, respectively. By comparing supplemented groups, it was observed a significant difference (p=0.04), the natural capsule more efficient than the synthetic, approximately 49.6%. Individually, 21.1% of the women provided below 4mg/day of &#945;-TOH, after supplementation for this index declined4.1%. Thus, maternal supplementation postpartum raised the levels of alpha-tocopherol in colostrum, and increased efficiency was observed with the natural form / A vitamina E consiste em oito formas quimicamente hom?logas, denominadas, alfa, beta, gama e delta, tocofer?is e tocotrien?is. Biologicamente, o alfa-tocoferol (&#945;-TOH) ? o mais importante. Comercialmente s?o encontradas duas formas de &#945;-TOH, uma natural (RRR-alfa-tocoferol) e outra sint?tica (all-rac-alfa-tocoferol). Ambas as formas s?o absorvidas no intestino, entretanto, no f?gado ocorre uma prefer?ncia em favor das formas 2R, devido ? prote?na de transfer?ncia de &#945;-TOH, apresentar maior afinidade a estes estereois?meros. Os neonatos s?o considerados grupo de risco para defici?ncia de vitamina E, principalmente os pr?-maturos, estes t?m o leite materno como a fonte alimentar para manuten??o dos n?veis s?ricos de &#945;-TOH. Sinais cl?nicos como trombocitose, anemia hemol?tica, fibroplasia retrolental, hemorragia intraventricular, displasia bronco pulmonar e degenera??o espinocerebelar podem ser encontrados caso ocorra uma baixa ingest?o de &#945;-TOH. Sendo assim, a suplementa??o materna nos p?s-parto com &#945;-TOH pode ser uma forma eficiente de aumentar os n?veis de vitamina E no leite materno e, consequentemente aumento no fornecimento do micronutriente para o rec?m-nascido. Entretanto, a maioria dos estudos com suplementa??o de vitamina E foram realizados em animais e s?o escassos os conhecimentos de sua suplementa??o em humanos, bem como, sobre sua efici?ncia para aumentar os n?veis de &#945;-TOH no leite humano, em fun??o da forma natural ou sint?tica. Participaram do estudo 109 mulheres, distribu?das em tr?s grupos: controle sem suplementa??o (GC) (n=36), suplementadas com a c?psula natural (GNAT) (n=40) e com a c?psula sint?tica (GSINT) (n=33). Foram coletadas amostras de sangue para determina??o do estado nutricional materno, e de colostro no contato inicial e ap?s 24 horas p?s-suplementa??o. As an?lises foram realizadas por Cromatografia L?quida de Alta Efici?ncia. Valores de &#945;-TOH no soro inferiores a 499,6 &#956;g/dL foram considerados como deficientes. Foram utilizados o teste de Kruskal Wallis e teste de Tukey para confirmar o aumento de alfa-tocoferol no leite e a efici?ncia das c?psulas administradas. O consumo di?rio de &#945;-TOH foi baseado na ingest?o di?ria de 500 mL de colostro pelo rec?m-nascido e comparada com o requerimento nutricional para crian?as de 0 ? 6 meses de idade, 4 mg/dia. As parturientes apresentaram concentra??o m?dia de &#945;-TOH no soro de 1016 ? 52, 1236 ? 51 e 1083 ? 61 &#956;g/dL, nos grupos GC, GNat e GSINT, respectivamente. N?o foram encontradas mulheres com defici?ncia. O GC n?o apresentou varia??o nas concentra??es de &#945;-TOH no colostro. Enquanto mullheres suplementadas com as formas natural e sint?tica aumentaram as concentra??es de &#945;-TOH no colostro em 57,6% e 39%, respectivamente. Ao comparar os grupos suplementados foi observado uma diferen?a significativa (p=0,04), sendo a c?psula natural mais eficiente que a sint?tica em aproximadamente 49,6%. Individualmente 21,1% das mulheres forneceram valores inferiores as 4mg/dia de &#945;-TOH, ap?s a suplementa??o este ?ndice declinou para 4,1%. Sendo assim, a suplementa??o materna no p?s-parto elevou os n?veis de alfa-tocoferol no colostro e maior efici?ncia foi observada com a forma natural

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