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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.
11

Resposta imuno-bioquímica e avaliação histológica da cartilagem articular de ratos artrose induzidos, frente ao tratamento com iontoforese isolada e de ácido L-ascorbico

Arruda, Maurício Ferraz de [UNESP] 24 November 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:30:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-11-24Bitstream added on 2014-06-13T20:40:39Z : No. of bitstreams: 1 arruda_mf_dr_arafcf.pdf: 1544944 bytes, checksum: 75a1678618fc45bbed80bdb04d417b13 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A osteoartrose se caracteriza pela degeneração articular, perda de cartilagem e alterações no osso subcondral. Pouco se sabe sobre a patogênese e mudanças que ocorrem na osteoartrose como também em seu reparo. As técnicas terapêuticas disponíveis podem resultar em alívio dos sintomas, mas não na regeneração do tecido lesado. Um dos métodos usuais para pesquisa em osteoartrose com o preceito de mimetizar esta situação e também realizada neste trabalho, é o modelo experimental utilizando a inoculação intra-articular de zymosan (Saccharamyces cerevisiae), gerando artrite em grau progressivo. A eletroterapia potencializa a reparação de tecidos conjuntivos representando uma alternativa na reparação de lesões da cartilagem hialina. O acido ascórbico é um dos precurssores do colágeno que junto com outras estruturas complexas como a trama de glicosaminoglicanas e proteoglicanas constitui a cartilagem. A utilização dessa técnica para administração do acido ascórbico em tecido biológico é fator substancial do presente trabalho. Objetivo: O objetivo do presente estudo foi verificar a resposta imuno-bioquímica e avaliar microscopicamente a cartilagem articular de ratos artrose induzidos, frente ao tratamento com iontoforese na presença e ausência de acido L - ascórbico. Materiais e Métodos: Ratos wistar machos divididos em 6 grupos de 6 animais cada um, diferenciados em grupos: controle positivo C+, controle negativo C-,gavagem com solução fisiológica GSF, gavagem com ácido ascórbico GAA, iontoforese solução fisiológica IFSF iontoforese com ácido ascórbico IFAA.Resultados: Histológicos demonstraram em coloração Hematoxilina e Eosina que com o grupo IFAA obteve normalidade da variável celularidade (40.1 mm2), e manutenção da cartilagem não calcificada (75.5mm) (p<0.05), sugerindo espessuras normais. Quanto ao grupo não tratado C+ apresentou-se menor... / Osteoarthritis is characterized by joint degeneration, loss of cartilage and subchondral bone changes. Little is known about the pathogenesis and changes that occur in osteoarthritis as well as in its repair. Available therapeutic techniques can result in relief of symptoms but not in the regeneration of injured tissue. One of the usual methods for research used in this study is the experimental model which uses intra-articular inoculation of zymosan (Saccharamyces cerevisiae), causing arthritis in progressive degree. Electrotherapy enhances the healing of tissues representing an alternative in the repair of hyaline cartilage injuries. Ascorbic acid is one of the forerunners of collagen which along with other complex structures like the chains of glycosaminoglycans and proteoglycans form the cartilage. The use of this technique for administration of ascorbic acid in biological tissue is a substantial factor in this study. Objective: The objective of this study was to investigate the immune-biochemical reply and evaluate microscopically the histology of articular cartilage in rats arthritis induced, compared to treatment with iontophoresis in the presence and absence of L - ascorbic acid. Methods: Male wistar rats were divided into 6 groups of 6 animals each, in different groups: positive control C+, negative control C-, gavage with saline solution GSS, gavage with ascorbic acid GAA, saline iontophoresis IPSS, iontophoresis with ascorbic acid IPAA. Results: Histological it was demonstrated that in hematoxylin and eosin staining the group that received IPAA obtained normality of variable (40.1 mm2), and maintenance of non calcified cartilage (75.5mm) (p<0.05), suggesting normal thickness. Regarding the untreated group C+, it presented lower average in the number of chondrocytes (13.0mm2), and with regard to the thickness of cartilage it had a higher average of calcified cartilage with... (Complete abstract click electronic access below)
12

Quality of Applesauce and Raspberry Puree Applesauce as Affected by Type of Ascorbic Acid, Calcium Salts and Chelators under Stress Storage Conditions

Goan, Eric Calvin 01 May 2011 (has links)
Applesauce prepared for the US military is processed as MRE (meals-ready-to-eat) in several forms including Type VI - Applesauce with raspberry puree, and Type VII - Carbohydrate enriched applesauce. Production of MRE applesauce starts with commercially prepared and thermally processed applesauce that is further processed by a military contractor. The further processing includes adjusting pH, ºBrix, and ascorbic acid level, packaging into pouches, and again thermally processing. Both types of the MRE applesauce are very much liked by troops, but under stress storage applesauce darkens and its consumption is drastically reduced. The overall goal of this project was to identify additives to be used during further processing in order to slow darkening when exposed to elevated temperatures during shipping and storage. The specific objective was to determine whether different types of ascorbic acid, calcium salts, or addition of chelators can reduce deterioration under stress storage. Applesauce (AS), applesauce with raspberry puree (RPAS), MRE AS (Type VII) and MRE RPAS (Type VI) for all experiments were provided by Sopakco, Bennettsville S.C. The research was carried out in three phases. From the Phase 1, we learned that Type VII and Type VI darkened at faster rates at the beginning of the storage, but the effects of storage at 50°C for more than 2 weeks overcame any differences caused by further processing. Phase 2 helped us determine the formulations for the processing on the industrial scale. The formulations were: 0.15% L-ascorbic-acid (AA), and 0.15% AA with 300 ppm EDTA for both AS and RPAS, with 0.83% calcium lactate gluconate (CLG) for AS, and 0.15% ascorbyl-palmitate for RPAS. The results from the Phase 3 indicated that AS with addition of CLG and RPAS with total of 0.18% AA had the least total color change. In all samples, accumulation of HMF was related to amount of ascorbic acid with exception of samples with Pal which had the lowest HMF content. Our results indicate that current MRE Types VI and VII may have better stability at stress storage if the level of AA is limited to 0.18% and 0.83% CLG is added to the AS formulation.
13

The role of cellular antioxidants (glutathione and ascorbic acid) in the growth and development of wild carrot suspension cultures

Earnshaw, Brent A. 01 January 1986 (has links)
No description available.
14

The breakdown of ascorbic acid at different temperatures and amounts of dissolved oxygen in orange juice

Ogsäter, Jens January 2014 (has links)
Vitamin C is an essential water soluble vitamin found mainly in fruits, vegetables and their derivatives. Orange juice is a popular thirst quencher and a convenient way to reach the daily recommended intake of vitamin C. The aim of this thesis was to determine how the vitamin C content in orange juice is affected by storage temperature and oxygen content in the product. Bottles of orange juice were stored at different temperatures. Regular orange juice was compared to juice where dissolved oxygen in product water had been decreased before mixing the juice. One other aim was to determine the efficiency of a stress test room where a higher temperature was supposed to simulate longer storage time. The study showed a larger non-linear loss of vitamin C over time in the bottles stored at the higher temperatures. The samples with less dissolved oxygen showed a higher vitamin C content after five and six months of storage in room temperature. For a storage time up to one week the loss of vitamin C in the stress test does not appear to be equal to the corresponding storage time in room temperature.KeywordsOrange juice, / Vitamin C är en livsnödvändig vattenlöslig vitamin som främst förekommer i grönsaker, frukter och produkter framställda från dessa. Apelsinjuice är en populär törstsläckare och ett enkelt sätt att få i sig sin dagliga dos C-vitamin. Syftet med denna rapport är att undersöka hur halten C-vitamin i apelsinjuice från Kiviks Musteri ändras beroende på lagringstemperatur och syrehalt i produktvatten. Apelsinjuice tillverkad från kranvatten jämfördes med juice tillverkad med vatten där syrehalten minskats genom kokning. Ett annat syfte var att fastställa effektiviteten för ett lagringsrum som simulerade en längre lagringsperiod genom att höja temperaturen. Resultaten visade att det var en större ickelinjär förlust av C-vitamin i flaskor som lagras vid en högre temperatur. Juiceflaskor med mindre mängd löst syre visade en lägre förlust av C-vitamin efter fem respektive sex månaders lagring i rumstemperatur. Förlusten av C-vitamin i juice lagrad en vecka i rummet med högre temperatur var ej den mängd som förutspåddes enligt företagets modell.
15

Vitamin C as a modifier of mammalian epigenetics: implications for adaptive immunity

Håkman, Jonna January 2013 (has links)
Ascorbic acid (AA), in popular speech vitamin C, is a commonly known nutrient. It is involved in several biological processes and deficiency can lead to scurvy. Recent publications have shown the impact of AA on epigenetic regulation in mice. Addition of AA, via enzymatic activity, enhances the generation of 5-hydroxymethylcytosine (5hmC), which is an intermediate in active demethylation of DNA. The role of AA on epigenetic changes in humans has to our knowledge never been studied. In this study, naïve CD4+ T cells from blood donors were used as a model system to investigate AAs possible role in methylation changes in the immune system. By using dot-blot assay, hydroxymethylated DNA immunoprecipitation (hmeDIP) and qPCR, changes in methylation executed by AA could be detected. A confirmation of AAs impact on epigenetic changes in mice was observed. AA enhanced the levels of 5hmC compared to untreated cells. The Jurkat cell line, a human T lymphocyte cell line, showed an opposite result. Treatment with AA decreased the levels of 5hmC compared to untreated cells. When comparing this result with the results obtained in human naïve T cells, the same observation was made. The difference between mouse and human in the ability of producing and metabolize AA could be a reason for this opposite result. Since AA had the ability to modify epigenetic changes in primary human CD4+ T cells, the results suggest that AA may have a function in the human immune system.
16

Airway antioxidant responses to oxidative air pollution and vitamin supplementation /

Behndig, Annelie F., January 2006 (has links)
Diss. (sammanfattning) Umeå : Umeå universitet, 2006. / Härtill 5 uppsatser.
17

ASCORBIC ACID AND THE FLAVIN-CONTAINING MONOOXYGENASE

BRODFUEHRER, JOANNE IRENE. January 1986 (has links)
Thesis (Ph. D.)--University OF MICHIGAN.
18

Remodelling of the periodontium in orthodontically treated guinea pigs on restricted vitamin C intake a thesis submitted in partial fulfillment ... in orthodontics ... /

Dierkes, J. Michael. January 1976 (has links)
Thesis (M.S.)--University of Michigan, 1976.
19

Remodelling of the periodontium in orthodontically treated guinea pigs on restricted vitamin C intake a thesis submitted in partial fulfillment ... in orthodontics ... /

Dierkes, J. Michael. January 1976 (has links)
Thesis (M.S.)--University of Michigan, 1976.
20

A mechanism for ascorbate induced cataract in human lens

Simpson, Gregory L. W. January 2001 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 2001. / Typescript. Vita. Includes bibliographical references (leaves 153-159). Also available on the Internet.

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