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Determinação e quantificação das vitaminas C e E associadas em produtos cosméticos / Determination and quantification of vitamins C and E associated in cosmetic productsMariana Mandelli de Almeida 18 September 2008 (has links)
A vitamina C e a vitamina E são antioxidantes naturais encontrados em diversas frutas e verduras frescas, em óleos vegetais e germem de trigo. Produtos cosméticos, contendo essas vitaminas em forma de ésteres, têm sido desenvolvidos e disponibilizados comercialmente, ressaltando-se que o aspecto natural dessas induz seu uso em cremes e loções. Por isso, torna-se necessário a validação de metodologias analíticas para identificar essas vitaminas em preparações cosméticas, tanto para o controle da qualidade do produto como para a segurança do consumidor. O presente trabalho tem como objetivo a validação das metodologias analíticas para determinação e quantificação do derivado do ácido ascórbico, tetraisopalmitato de ascorbila e o princípio ativo acetato de tocoferila que estão associados nas formulações cosméticas. A técnica de espectrofotometria no ultravioleta (UV) e a análise térmica foram empregadas na caracterização desses princípios ativos. Para a quantificação dos ativos foram desenvolvidas metodologias analíticas empregando as seguintes técnicas: espectrofotometria derivada no UV; eletroforese capilar e cromatografia líquida de alta eficiência (CLAE). A metodologia desenvolvida por espectrofotometria derivada no UV não demonstrou ser aplicável devido à interferência dos excipientes presentes na formulação. Para determinação dos ativos tetraisopalmitato de ascorbila e acetato de tocoferila, foi validado um método por CLAE em fase reversa, empregando-se a coluna Synergi Hidro® C18, fase móvel metanol:2-propanol (25:75), vazão 1,0 mL/min e detecçao UV à 222 nm. As amostras foram extraídas sem grande complexidade e os ativos puderam ser determinados em 3 min e 6 min, para o acetato de tocoferila e o tetraisopalmitato de ascorbila respectivamente. O desenvolvimento da metodologia por eletroforese capilar utilizando-se a técnica de MEEKC (Cromatografia Eletrocinética em Microemulsão) usando a microemulsão óleo-aquosa não demonstrou ser adequada para determinação dos princípios ativos em estudo, sendo que o trabalho terá como perspectivas a tentativa da MEEKC usando a microemulsão aquosa-oleosa. / Vitamin C and vitamin E are natural antioxidants found in many fruits and fresh vegetables, vegetable oils and seed wheat. Cosmetics containing these vitamins in the form of esters have been developed and made available commercially, highlighting the fact that the \"natural\" induces its use in these creams and lotions. Than, it is necessary the validation of analytical methodologies to identify these vitamins in cosmetic preparations, both for the control of product quality and for the safety of consumers. The present work aims the validation of analytical methodologies for determining and quantifying the derivative of ascorbic acid, ascorbyl tetraisopalmitate and the active tocopheryl acetate that are associated in cosmetic formulations. The techniques of UV spectrophotometry and the thermal analysis were used in the characterization of these active ingredients. For the quantification of the actives, analytical methodologies were developed using the following techniques: the UV first-derivative spectrophotometry (UVD), high performance liquid chromatography (HPLC) and capillary electrophoresis (CE). The methodology developed by UV first-derivative spectrophotometry do not showed to be applicable due to the interference of excipients in the formulation. To determine the actives ascorbyl tetraisopalmitate and tocopheryl acetate, a method has been validated by reverse-phase HPLC, using the column Synergi Hidro ® C18, mobile phase methanol :2-propanol (25:75), flow rate 1.0 mL / min and UV detection 222 nm. The samples were extracted without great complexity and the actives could be determined in 3 min and 6 min, for the tocopheryl acetate and ascorbyl tetraisopalmitate respectively. The development of methodology for capillary electrophoresis using the technique of MEEKC (Microemulsion Electrokinetic Chromatography) using the oil-in-water (o/w) microemulsion do not showed to be suitable for determination of active ingredients in the study, and that the work will attempt the prospects of using MEEKC the water-in-oil (w/o) microemulsion.
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Vegetariánství a těhotenství / Vegetarianism and pregnancyŠimončičová, Renáta January 2017 (has links)
Introduction: Master's thesis is focused on the problems facing vegetarianism during pregnancy. Further study is focused particularly on the exploration of pregnant vegetarian's dietary habits. Object: The theoretical part's target is to familiarise readers with vegetarianism and pregnant vegetarian's diet. The practical part is focused on pregnant vegetarian's dietary habits, finding if those women are drawn to alternatives relating to decisions regarding their own bodies and if they will follow a vegetarian diet with their children. Methods: The survey was conducted through an anonymous online questionnaire. The data obtained is represented in graphs and tables. One part of the work is devoted to the analysis of the data. Results: The theoretical part shows that compilation of a properly assembled vegetarian diet during pregnancy requires enough relevant information. The survey shows that the majority of respondents eat mostly varied food according to the principles of healthy nutrition with respect to vegetarianism. The greater part of the respondents tend to alternatives in relation to decisions about their own bodies. Absolute majority of respondents stated they are not going to lead or are not leading their children to vegetarianism. Conclusion: Proper preparation of meatless diet requires...
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Estabilidade das vitaminas antioxidantes em amostras de pólen apícola / Stability of antioxidants vitamins in bee pollen sampleIllana Louise Pereira de Melo 18 September 2008 (has links)
O pólen apícola apresenta elevadas porcentagens de nutrientes e pode ser utilizado como suplemento nutricional na alimentação humana. Este trabalho teve por objetivo principal avaliar a estabilidade das vitaminas antioxidantes (vitamina C, E e β-caroteno) em pólen apícola durante um ano de estocagem. Foram adquiridos entre os meses de março e abril 2007 seis lotes de pólen apícola in natura e desidratado, diretamente de entrepostos de comercialização de produtos apícolas. Foram analisadas as concentrações das três vitaminas no tempo zero e em seguida amostras foram armazenadas, em embalagens fornecidas pelo produtor, sob três formas: a temperatura ambiente; a temperatura ambiente, porém protegida da luz; em freezer. Foi utilizado o método títulométrico para análise de vitamina C. Para β-caroteno utilizou-se a cromatografia em coluna aberta no tempo zero e cromatografia líquida de alta eficiência após 6 e 12 meses de estocagem. Esta última foi utilizada para as análises da vitamina E. Foram realizadas ainda análises polínica e de composição centesimal. Foram encontradas as seguintes variações: 14±0,25 a 119±1,961 µg/g para vitamina C, 19,43±1,70 a 45,00±3,61µg/g para vitamina E 3,77±0,10 a 99,27±2,45 µg/g para β-caroteno em amostras frescas. Após processo de desidratação, houve uma alteração de 67,1% para mais na vitamina C (diferença significativa p<0,05), uma perda de 18,7% para vitamina E e de 15,6% para β-caroteno. O valor pró-vitamínico A das amostras desidratadas variou de 0,26 a 6,48 µg/g. A composição centesimal das amostras estudadas está de acordo com as especificações estabelecidas pela legislação brasileira em vigor (Instrução Normativa N° 3, de 19/01/2001). Houve grande variabilidade dos tipos polínicos encontrados nas amostras e alguns deles estiveram fortemente correlacionados com os teores de vitamina C (Myrtaceae), de β-caroteno (Arecaceae, Cecropia e Fabaceae) e de lipídeos (Arecaceae e Fabaceae). Outros estiveram correlacionados de forma negativa, como é o caso dos Mimosa caesalpineafolia e Poacease com os níveis de β-caroteno, do tipo Arecaceae com as proteínas e do tipo Mimosa caesalpineafolia com os lipídeos. A estocagem em freezer foi a condição mais eficiente na conservação das três vitaminas e a perda na estocagem a temperatura ambiente exposto a luz e protegido da luz foram semelhantes. Considerando-se as três condições estudadas, a vitamina E parece ser mais preservada durante estocagem quando comparada à vitamina C e ao β-caroteno. Entretanto, conforme teste estatístico realizado, houve perdas significativas (p<0,05) apenas para vitamina C em todas as condições estudadas quando comparadas a sua concentração inicial (tempo 0). / Bee pollen contains high percentages of nutrients and it can be used as a nutritional supplement for human feeding. The aim of this work was to evaluate the stability the antioxidant vitamins (vitamin C, E and β-carotene) in bee pollen during one year of storage. Six batches of fresh and dried bee pollen pellets were acquired in 2007 March and April from bee products warehouses. The three vitamins were quantified and then stored under three forms in packages supplied by the producer: in room temperature, in room temperature protected from light and frozen. Vitamin C was quantified by potentiometric titration. The open column chromatography was used for β-carotene analyses in the zero time and the high performance liquid chromatography after 6 and 12 months storage. This last one was used for the vitamin E analyses. The centesimal composition and botanical characterization of the bee pollen were obtained. Vitamin content in fresh samples varied between 14±0.25 and 119±1.96µg/g for vitamin C; 19.43±1.70 and 45.00±3.61µg/g for vitamin E and 3.77±0.10 and 99.27±2.45µg/g for β-carotene. After the drying process a significant alteration 67.1 % for more in the vitamin C (p<0.05), a losses of 18.7% for vitamin E and 15.6% for β-carotene were observed. The provitamin A value was between 0.26 and 6.48µg/g. The proximal composition of the samples studied presented results which were ali accordance to the specifications established for the Brazilian regulation (Normative Instruction N° 3, 19/01/2001). A great variability of the pollen types was found in the samples and some of them were strongly correlated with the vitamin C (Myrtaceae), β-carotene (Arecaceae, Cecropia and Fabaceae) and lipids (Arecaceae and Fabaceae). Other ones were negatively correlated, such as Mimosa caesalpineafolia and Poaceae types with β-carotene, Arecaceae type with proteins and Mimosa caesalpineafolia type with lipids. Storage in freezer was more efficient to keep the vitamins and the losses at room temperature storage when exposed to light and in the dark were similar. Vitamin E was more preserved during the storage when compared to vitamin C and β-carotene. However, only vitamin C presented significant statistical losses (p<0.05) in ali of the studied conditions when compared to its initial content.
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Vitaminas do complexo B e ferro em farinhas de cereais / Complex B vitamins and iron in cereal flourAna Elisa Ferreira Presoto 27 November 2006 (has links)
As vitaminas do complexo B e o ferro estão presentes em farinhas de cereais, alimentos amplamente consumidos pela população brasileira. O teor natural desses compostos em farinhas de cereais pode ser significativo no cálculo de uma dieta bem balanceada e o consumo de produtos industrializados enriquecidos com vitaminas do complexo B e ferro ajuda a contribuir na ingestão diária recomendada desses micronutrientes. Tabelas Mundiais de Composição de Alimentos apresentam dados incompletos das vitaminas do complexo B e do ferro em farinhas de cereais. No Brasil, a adição de ácido fólico e ferro em farinhas de milho e trigo produzidas para fins industriais é obrigatória desde 2002. Deste modo, para a adequação dos teores de rotulagem de produtos enriquecidos com vitaminas e ferro se fazem necessários o desenvolvimento e a validação de metodologias analíticas confiáveis e sensíveis para análise de vitaminas do complexo B e ferro em alimentos que apresentam tais micronutrientes em quantidades baixas, porém significativas, que correspondem aos teores naturalmente presentes. O objetivo do presente trabalho é a avaliação dos teores de sete vitaminas do complexo B (B1, B2, B6, ácido pantotênico, ácido fólico, niacina e biotina) e ferro em cinco farinhas de cereais (aveia, arroz, cevada, milho e trigo) utilizadas como matéria prima de produtos enriquecidos na indústria alimentícia, utilizando métodos validados. / Complex B vitamins and iron are present in some cereal foods, a kind of food largely consumed by Brazilian people. The total of these micronutrients can be significant at the dairy ingestion portion and in the consume of industrialized products enriched with complex B vitamins and iron contribute in the recommended dietary intake of these micronutrients. Table of food composition do not report complete data of complex B vitamins and iron in cereal flours. In Brazil, since 2002 the addition of folic acid and iron in com and wheat flours is compulsory. Therefore, to adapt the label of some products enriched with vitamins and iron, there is necessary the development and validation of analytical methods. These methods must be reliable and with enough sensitivity to analyse complex B vitamins and iron, in low concentration, wich are natural content in food. The purpose of this work is the evaluation, with validated methods, of the content of seven complex B vitamíns (B1, B2, B6, niacin, folic acid, pantothenic acid and biotin) and iron in five kinds of cereal flours (oat, rice, barley, com and wheat). These raw materiais are used in food industry in order to enrich the industrialized products.
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Vliv hydroxykyselin na rychlost transdermální absorpce vybraných farmaceuticky aktivních ingrediencí / Influence of hydroxyacids on transdermal absorption of selected active pharmaceutical ingredientsVolhinava, Anastasiya January 2020 (has links)
Diploma thesis deals with the experimental study of transdermal transport of individual hydroxyacids and their combination with water-soluble vitamins. During this work the literature review was prepared, which was focused on the use of hydroxyacids in the cosmetic and pharmaceutical industries. At the same time the current state of use of water-soluble vitamins for topical applications was studied. Series of experiments was performed using Franz diffusion cells to simulate transdermal transport in vitro across cutaneous, synthetic and artificial Strat M ® membranes. The methodology of sample preparation and analysis of their transport properties was invented and optimized. The optimized methodology was subsequently used in a series of diffusion experiments in which the penetrated amount of hydroxyacids was analyzed by ion chromatography. The concentration of water-soluble vitamins was determined by HPLC. All examined active substances demonstrate positive penetration properties. The best results were obtained with combination of glycolic acid with pyridoxine.
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"Výživa sportovců v porovnání s osobami se sedavým způsobem života." / "Nutrition of athletes compared to people with a sedentary way of life."Kubíková, Kristýna January 2021 (has links)
Introduction: The main topic of this diploma thesis was the nutrition of athletes compared to people with a sedentary lifestyle. Aim: The main goal of the thesis was the nutrition of athletes compared to people with a sedentary lifestyle using analyzing dietary regimen. Material and methods: We evaluated the dietary regimen of 40 women at the age of 20- 30 years old. Women were divided into the groups of non-athletes ("sedentary people") and women who exercise fitness sports ("fitness people"). Their average age was in the range of 25,3-26 years. Respondents filled out the form with their dietary regimen for three days using a 24-hod recall. Records where evaluated with using an extensive food database which was created at the Institute of Physical Education, First of Medicine, Charles University. Student's two-tailed unpaired mean t-test was used to compare the groups. We used the F-test to analysing a equation scattering before using t-test. Results: Group of fitness athletes consumed average 335 kcal less total energy (p = 0.008), 15.17 g more plant-based proteins (p = 0.031), 15.24 g less fats (p = 0.025) and 13.23 g less animal fat (p = 0.044). The results for other nutrients weren't statistically significant, but from a nutritional point of view they provided an interesting overview of eating...
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Investigating the porphyrias through analysis of biochemical pathways.Ruegg, Evonne Teresa Nicole January 2014 (has links)
ABSTRACT
The porphyrias are a diverse group of metabolic disorders arising from diminished
activity of enzymes in the heme biosynthetic pathway. They can present with acute
neurovisceral symptoms, cutaneous symptoms, or both. The complexity of these
disorders is demonstrated by the fact that some acute porphyria patients with the
underlying genetic defect(s) are latent and asymptomatic while others present with
severe symptoms. This indicates that there is at least one other risk factor required in
addition to the genetic defect for symptom manifestation. A systematic review of the
heme biosynthetic pathway highlighted the involvement of a number of micronutrient
cofactors. An exhaustive review of the medical literature uncovered numerous reports
of micronutrient deficiencies in the porphyrias as well as successful case reports of
treatments with micronutrients. Many micronutrient deficiencies present with
symptoms similar to those in porphyria, in particular vitamin B6. It is hypothesized
that a vitamin B6 deficiency and related micronutrient deficiencies may play a major
role in the pathogenesis of the acute porphyrias. In order to further investigate the
porphyrias, a computational model of the heme biosynthetic pathway was developed
based on kinetic parameters derived from a careful analysis of the literature. This
model demonstrated aspects of normal heme biosynthesis and illustrated some of the
disordered biochemistry of acute intermittent porphyria (AIP). The testing of this
model highlighted the modifications necessary to develop a more comprehensive
model with the potential to investigated hypotheses of the disordered biochemistry of
the porphyrias as well as the discovery of new methods of treatment and symptom
control. It is concluded that vitamin B6 deficiency might be the risk factor necessary
in conjunction with the genetic defect to trigger porphyria symptoms.
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Caracterização do pólen apícola e utilização de vitaminas anti-oxidantes como indicadoras do processo de desidratação / Bee pollen characterization and antioxidants vitamins as indicators of the efficiency of dryness processOliveira, Karla Cristina Lima da Silva 14 February 2006 (has links)
O pólen apícola é o resultado da aglutinação do pólen das flores efetuada pelas abelhas, mediante acréscimo de substâncias salivares e pequenas quantidades de néctar ou mel. Trata-se de um produto consumido devido a seus benefícios nutricionais e terapêuticos. Sua importância nutricional é reconhecida por ser uma fonte protéica de elevado valor biológico, apresentando ainda carboidratos, lipídeos e minerais em sua composição, além das vitaminas do complexo B, C, E, β-caroteno (como pró-vitamina A) e D; características estas que variam de acordo com sua origem botânica. Este trabalho teve como objetivos: caracterizar o pólen apícola produzido em diferentes épocas de coleta; obter dados científicos nacionais sobre o valor vitamínico de pólen apícola, relacionando-o com sua origem botânica e avaliar o efeito de dois tipos de processos de secagem do pólen apícola nos teores das vitaminas antioxidantes (β-caroteno, como pró-vitamina A, vitamina C e E), considerando-se que estas vitaminas podem ser degradadas durante o processamento. Foram analisados os teores de vitaminas em 10 lotes de pólen apícola fresco, sendo 5 coletados em abril e 5 em outubro de 2005. Os lotes frescos de pólen apícola foram desidratados por um método convencional (desidratação à 42° C) e por um método alternativo (desidratação a 30-35° C). Além disso, foi realizada a identificação dos tipos polínicos encontrados nas amostras frescas de pólen apícola e a associação com o teor de vitaminas encontradas. Os valores das vitaminas determinados nas amostras frescas de pólen apícola variaram entre 13,5 e 42,5 µg/g para vitamina E; 56,3 e 198,9 (µg/g) para β-caroteno e entre 273,9 e 560,3 µg/g para vitamina C. De acordo com os resultados concluiu-se que a origem botânica e a época de coleta influenciaram no teor das vitaminas encontradas, interferindo inclusive na classificação da amostra como fonte ou não de determinada vitamina. Além disso, foi observado que o processamento alternativo foi mais eficaz que o processamento convencional na manutenção dos teores de todas as vitaminas em estudo. / Bee-collected pollen (bee pollen) is highly consumed around the world due its nutritive and therapeutic value. It contains proteins, carbohydrates, lipids, minerals and vitamins of complex B, vitamin C, D, E and totals carotenoids. However there are few literature data correlating nutritional composition with botanical origin and thermal process. The aim of this study was to quantify vitamins C, E and beta-carotene (provitamin A) in fresh and processed samples of bee pollen, correlating them with botanical origin. In addition, to evaluate the effect of drying process in the vitamin content. Ten samples of fresh bee pollen were collected, five in April and five in October of 2005. Samples of fresh bee pollen were dried by conventional method (drying at 42° C) and by an alternative method (drying at 30-35° C). The fresh bee pollen and the processed ones were assayed regarding their vitamin contents (n=30). Vitamin C was quantified by potentiometric titration, vitamin E by HPLC-normal phase and beta-carotene by open column chromatography. The date from botanical characterization of the bee pollen were obtained and correlated to the vitamins content. Vitamin content in fresh samples varied between 13,5 and 42,5 µg/g for vitamin E; 56,3 and 198,9 (µg/g) for β-carotene and 273,9 and 560,3 µg/g for vitamin C. The alternative drying method was more efficient that conventional one in retaining the vitamins. It was also concluded that the botanical origin and collecting season influenced the vitamin contents. Being important factor to predict if bee pollen was source or not of each vitamin.
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Rôle de PGC-1α dans le système cardiovasculaire : recherche d’activateurs cœur-spécifiques et étude de ses mécanismes de régulation dans le muscle lisse aortique / PGC-1 alpha role in the cardiovascular system : search for inducers of its expression in heart and study of signaling pathways controlling PGC-1 alpha in aortic smooth muscleRuiz, Matthieu 14 September 2012 (has links)
L’insuffisance cardiaque (IC) reste la cause majeure de morbimortalité dans les pays industrialisés justifiant ainsi la recherche de traitements plus ciblés. Caractérisée par des désordres métaboliques importants qui impliquent notamment une dysfonction mitochondriale, le métabolisme énergétique apparait comme une composante majeure du développement de l’IC. Ces dernières années, le co-activateur transcriptionnel PGC-1α a été proposé comme un acteur central du contrôle de la fonction mitochondriale et constitue ainsi une cible thérapeutique d’intérêt. Ainsi, l’objectif principal de ce travail est de développer un test cellulaire robotisé permettant la recherche d’activateurs de PGC-1α dans un contexte cardiaque.La mise en place de ce test cellulaire de criblage dans des cellules H9c2 différenciées en cellules pseudo-cardiaques a permis l’identification de trois familles majeures : les hormones stéroïdiennes, les vitamines B et les acides gras, capables d’activer l’expression de PGC-1α et par ce biais d’induire une biogenèse mitochondriale ainsi qu’une augmentation de la respiration mitochondriale. La validation de ces effets dans des cardiomyocytes de rat adulte a permis d’une part de valider la pertinence du test et du choix du modèle cellulaire et d’autre part de vérifier qu’une induction de l’expression de PGC-1α se répercute bien sur la cascade transcriptionnelle de la biogenèse mitochondriale. Ce test constitue donc un atout majeur dans le recherche de nouveaux activateurs de PGC-1α pour mieux comprendre ses mécanismes de régulation dans le cœur, mais offre aussi des perspectives intéressantes pour la recherche de composés pharmacologiques à visée thérapeutique.Par ailleurs, peu de connaissances sont disponibles dans la littérature concernant le contrôle de la biogenèse mitochondriale dans le muscle lisse vasculaire et plus particulièrement dans l’hypertension artérielle. Ainsi, la deuxième partie de ce travail a été de caractériser la biogenèse mitochondriale dans un contexte d’hypertension. A travers l’utilisation d’un modèle expérimental d’hypertension et après confirmation dans des cellules musculaires lisses en culture, nous avons montré une induction importante de la biogenèse mitochondriale dans l’hypertension par un mécanisme stress oxydant-dépendant. De plus, cette induction est corrélée à une forte activation de la CaMKII, totalement bloquée par la présence d’un anti-oxydant : le resvératrol. Ces résultats suggèrent donc un contrôle de la biogenèse mitochondriale dépendante de la balance pro/anti-oxydante via l’activation de la CaMKII dans le muscle lisse vasculaire. / Heart failure (HF) is still the major cause of morbimortality in industrialized countries that justify the research of new treatments. Characterized in part by metabolic disorders including mitochondrial dysfunction, energetic metabolism appears as an essential component in HF development. These last years, PGC-1α has been proposed as a central actor of mitochondrial function control and thus as a therapeutic target of interest.The development of a cellular robotized assay in cardiac-like differentiated H9c2 cells allowed identification of three families: steroid hormones, B vitamins and fatty acids, able to induce the expression of PGC-1α and thus up-regulate mitochondrial biogenesis and mitochondrial respiration. The validation of these effects in adult rat cardiomyocytes lets in the one hand to validate the suitability of the assay and in the other hand to confirm that PGC-1α induction leads to mitochondrial biogenesis activation. Consequently, this assay constitutes a major asset to find new activators of PGC-1α to better understand its regulation in heart and provides interesting perspectives for the research of therapeutic pharmacologic compounds.Mechanisms controlling mitochondrial biogenesis in response to hypertension in vascular smooth muscle remain unclear. In this context, the second part of this work was to identify how mitochondrial biogenesis is modulated in arterial hypertension. Using an experimental model of hypertension and after validation in cultivated smooth muscle cells, we show a mitochondrial biogenesis induction in response to hypertension in relation with an increase in oxidative stress. Moreover, this induction is associated with a significant increase in CaMKII activity which was totally blocked by an antioxidant: resveratrol. These results suggest a regulation of mitochondrial biogenesis by oxidative stress via a CaMKII mechanism in vascular smooth muscle.
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Caracterização do pólen apícola e utilização de vitaminas anti-oxidantes como indicadoras do processo de desidratação / Bee pollen characterization and antioxidants vitamins as indicators of the efficiency of dryness processKarla Cristina Lima da Silva Oliveira 14 February 2006 (has links)
O pólen apícola é o resultado da aglutinação do pólen das flores efetuada pelas abelhas, mediante acréscimo de substâncias salivares e pequenas quantidades de néctar ou mel. Trata-se de um produto consumido devido a seus benefícios nutricionais e terapêuticos. Sua importância nutricional é reconhecida por ser uma fonte protéica de elevado valor biológico, apresentando ainda carboidratos, lipídeos e minerais em sua composição, além das vitaminas do complexo B, C, E, β-caroteno (como pró-vitamina A) e D; características estas que variam de acordo com sua origem botânica. Este trabalho teve como objetivos: caracterizar o pólen apícola produzido em diferentes épocas de coleta; obter dados científicos nacionais sobre o valor vitamínico de pólen apícola, relacionando-o com sua origem botânica e avaliar o efeito de dois tipos de processos de secagem do pólen apícola nos teores das vitaminas antioxidantes (β-caroteno, como pró-vitamina A, vitamina C e E), considerando-se que estas vitaminas podem ser degradadas durante o processamento. Foram analisados os teores de vitaminas em 10 lotes de pólen apícola fresco, sendo 5 coletados em abril e 5 em outubro de 2005. Os lotes frescos de pólen apícola foram desidratados por um método convencional (desidratação à 42° C) e por um método alternativo (desidratação a 30-35° C). Além disso, foi realizada a identificação dos tipos polínicos encontrados nas amostras frescas de pólen apícola e a associação com o teor de vitaminas encontradas. Os valores das vitaminas determinados nas amostras frescas de pólen apícola variaram entre 13,5 e 42,5 µg/g para vitamina E; 56,3 e 198,9 (µg/g) para β-caroteno e entre 273,9 e 560,3 µg/g para vitamina C. De acordo com os resultados concluiu-se que a origem botânica e a época de coleta influenciaram no teor das vitaminas encontradas, interferindo inclusive na classificação da amostra como fonte ou não de determinada vitamina. Além disso, foi observado que o processamento alternativo foi mais eficaz que o processamento convencional na manutenção dos teores de todas as vitaminas em estudo. / Bee-collected pollen (bee pollen) is highly consumed around the world due its nutritive and therapeutic value. It contains proteins, carbohydrates, lipids, minerals and vitamins of complex B, vitamin C, D, E and totals carotenoids. However there are few literature data correlating nutritional composition with botanical origin and thermal process. The aim of this study was to quantify vitamins C, E and beta-carotene (provitamin A) in fresh and processed samples of bee pollen, correlating them with botanical origin. In addition, to evaluate the effect of drying process in the vitamin content. Ten samples of fresh bee pollen were collected, five in April and five in October of 2005. Samples of fresh bee pollen were dried by conventional method (drying at 42° C) and by an alternative method (drying at 30-35° C). The fresh bee pollen and the processed ones were assayed regarding their vitamin contents (n=30). Vitamin C was quantified by potentiometric titration, vitamin E by HPLC-normal phase and beta-carotene by open column chromatography. The date from botanical characterization of the bee pollen were obtained and correlated to the vitamins content. Vitamin content in fresh samples varied between 13,5 and 42,5 µg/g for vitamin E; 56,3 and 198,9 (µg/g) for β-carotene and 273,9 and 560,3 µg/g for vitamin C. The alternative drying method was more efficient that conventional one in retaining the vitamins. It was also concluded that the botanical origin and collecting season influenced the vitamin contents. Being important factor to predict if bee pollen was source or not of each vitamin.
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