Spelling suggestions: "subject:"omega"" "subject:"ômega""
81 |
Antioksidacinio aktyvumo nustatymas preparatuose, turinčiuose omega – 3 riebalų rūgščių / Evaluation of antioxidant activity of preparations containing omega - 3 fatty acidKiškytė, Karolina 18 June 2014 (has links)
Darbo tikslas: nustatyti antioksidacinį preparatų, turinčių omega – 3 riebalų rūgščių, aktyvumą, palyginti jį su preparatų sudėtimis, atlikti vaistinės asortimento analizę.
Darbo uždaviniai:
Atlikti preparatų antioksidacinio aktyvumo tyrimą DPPH metodu.
Atlikti preparatų palyginamąją analizę vertinant sudėtis.
Išnagrinėti omega – 3 riebalų rūgščių turinčių preparatų pasiūlą vaistinėse.
Metodai: antioksidacinis aliejų aktyvumas tirtas spektrofotometriškai naudojant 2,2-difenil-1-pikrilhidrazilo (DPPH) laisvojo radikalo sujungimo metodą.
Pasirinktų linų sėmenų, kanapių sėklų, judros, rapsų, kviečių gemalų, graikinių riešutų aliejų bei žuvų taukų sudėtys vertintos ir lygintos literatūros analizės metodu.
Tyrime naudotų aliejų paplitimas vaistinės asortimente nustatytas renkant duomenis vaistinėse bei elektroninėse vaistinių parduotuvėse.
Rezultatai: nustatytas antioksidacinis aktyvumas (išreikštas inaktyvuoto DPPH % ±SD) kviečių gemalų aliejaus 53,59 ± 9,45, žuvų taukų 22,58 ± 5,38, judros aliejaus 22,40 ± 4,74, linų sėmenų aliejaus 22,17 ± 2,64, kanapių sėklų aliejaus 19,05 ± 1,54, graikinių riešutų aliejaus 18,66 ± 4,10, rapsų aliejaus 17,04 ± 2,68. Palyginus rezultatus ir literatūroje pateiktus duomenis nustatyta, kad nėra ryšio tarp aliejuje esančio omega – 3 riebalų rūgščių kiekio ir antioksidacinio aktyvumo, tačiau yra statistiškai patikimas ryšys tarp antioksidacinio aktyvumo ir sudėtyje esančio vit.E kiekio. Įvertinus vaistinės asortimentą nustatyti 75 žuvų taukų... [toliau žr. visą tekstą] / Objective of work: To estimate the antioxidant activity of preparations containing omega - 3 fatty acids; compare it with constitution of preparations; to execute the analysis of pharmacy range.
Main tasks: to estimate the antioxidant activity by using DPPH method.
To compare preparations by evaluating their constitutions.
To execute the analysis of pharmacy range.
Methods: antioxidant activity determined by using 2,2 – diphenyl-1-picrylhidrazyl free radical scavenging method.
The constituents of flax seed, hemp seed, camelina, rapeseed, wheat germ, walnut and fish oil were evaluated by literature analysis.
The data of prevalence of selected oils in pharmacy range was collected in the pharmacies and their online-shops.
Results: antioxidant activity of wheat germ oil was 53,59 ± 9,45%, fish oil 22,58 ± 5,38%, camelina oil 22,40 ± 4,74%, flax seed oil 22,17 ± 2,64%, hemp seed oil 19,05 ± 1,54%, walnut oil 18,66 ± 4,10%, rapeseed oil 17,04 ± 2,68%. A comparison of the results showed that there is no significant relationship between amount of omega – 3 fatty acids and the antioxidant activity of the oil, but there is a statistically significant relationship between the amount of tocopherols and the antioxidant activity. The evaluation of the pharmacy range showed 75 fish oil products, 10 products containing flax seed oil, 9 wheat germ oil, 6 hemp seed oil, 3 products with camelina oil, 2 rapeseed oil, and only one product containing walnut oil.
Conclusions:
The highest... [to full text]
|
82 |
Antiarrhythmic mechanisms of omega-3 polyunsaturated fatty acids in rat ventricular cardiomyocytes / Wayne R. Leifert.Leifert, Wayne R. January 2001 (has links)
Includes bibliographical references (leaves 237-257). / xx, 257 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the mechanisms underlying the antiarrhythmic effects of omega-3 polyunsaturated fatty acids using adult rat ventricular cardiac myocytes. / Thesis (Ph.D.)--Adelaide University, Dept. of Physiology, 2001
|
83 |
Measurement of fish consumption in population-based studies of cancer /Mina, Kym Deanne. January 2007 (has links)
Thesis (Ph.D.)--University of Western Australia, 2007.
|
84 |
Fettsäurenmuster im Liquor cerebrospinalis von Erwachsenen und KindernGroßmann, Antje, January 2007 (has links)
Ulm, Univ. Diss., 2006.
|
85 |
Fontes de óleo na dieta e sua importância no desempenho e na imunidade de frangos de corteRibeiro, Sheila Cardoso [UNESP] 20 August 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:18Z (GMT). No. of bitstreams: 0
Previous issue date: 2010-08-20Bitstream added on 2014-06-13T19:14:36Z : No. of bitstreams: 1
ribeiro_sc_me_araca.pdf: 191988 bytes, checksum: 6ae04c780c812f7133db1a6434eef76f (MD5) / Foi avaliado o efeito do uso de óleos ricos em ácidos graxos polinsaturados ômega-3 na dieta de frangos de corte sobre o desempenho e a resposta imune humoral e celular à vacinação. Foram comparadas dietas formuladas com óleo de soja (OS), linhaça (OL) ou sardinha (OP), fornecidas a 240 frangos da linhagem Cobb, divididos em 24 grupos de 10 aves cada, num arranjo experimental 3x2 (3 tipos de óleo e 2 situações vacinais) e 4 repetições. O consumo de ração, o ganho de peso e a conversão alimentar foram avaliados aos 21, 35 e 42 dias. Metade dos grupos foi vacinado contra doença de Newcastle. A produção de anticorpos, avaliada 15 dias após a vacinação pelo método de ELISA e expressa em densidade óptica a 450nm (D.O.450nm), foi maior entre as aves alimentadas com ração com OS (P<0,05). Nos grupos alimentados com OL e OP as médias de D.O.450nm não diferiram significativamente entre vacinados e não vacinados (P>0,05). A resposta linfoproliferativa das aves vacinadas foi maior independente do tipo de óleo utilizado (P<0,05). Na análise de desempenho não houve interferência da fonte de óleo ou da vacinação sobre o ganho de peso e peso vivo. Entre as aves vacinadas a pior média de conversão alimentar correspondeu à dieta com OS. Além disso, entre as aves que receberam dieta com OS, a vacinação piorou significativamente a conversão alimentar, considerando todo o período experimental (P<0,05). Já entre as aves que receberam dieta com OL ou OP, não houve diferença na conversão alimentar entre os grupos vacinados e não vacinados (P>0,05). Estes resultados demonstram que a reação maior ao desafio vacinal prejudicou o desempenho das aves alimentadas com OS. / The effect of the use of oils rich in omega-3 polyunsaturated fatty acids in the diet of broiler on performance and humoral immunity and cellular response to vaccination were evaluated. Diets were compared with soybean oil (OS), linseed (OL) or sardine (OP), supplied to 240 broiler, Cobb, divided into 24 groups of 10 birds each in a 3x2 factorial arrangement (3 types of oil and two vaccine situations) and 4 replications. Feed intake, weight gain and feed conversion were evaluated at 21, 35 and 42 days. Half of the groups were vaccinated against Newcastle disease. The production of antibodies evaluated 15 days after vaccination by ELISA and expressed as optical density at 450 nm (D.O.450nm) was higher in birds fed OS (P<0.05). In groups fed OL and OP, the mean of D.O.450nm did not differ significantly between vaccinated and unvaccinated (P>0.05). The lymphoproliferative response of vaccinated birds was higher, regardless of the type of oil used (P<0.05). In the performance analysis, there was no interference from the source of oil or of vaccination on weight gain and body weight. Among those vaccinated, the worst average feed conversion corresponded to the diet OS. Moreover, among the birds fed OS, vaccination has significantly worsened feed conversion, considering the entire experimental period (P<0.05). Among the birds fed OL or OP, there was no difference in feed conversion between vaccinated and unvaccinated groups (P>0.05). These results demonstrate that the greatest reaction to the challenge vaccine affected performance of birds fed OS.
|
86 |
Avaliação do estresse oxidativo em humanos e em animais suplementados com ácidos graxos polinsaturados omega-3 / Evaluation of oxidative stress in humans and animals supplemented with Omega-3 polyunsaturated fatty acidsVania Claudia Barros Monteiro 24 April 2007 (has links)
Ácidos graxos polinsaturados Omega-3 (n-3 PUFA) tais como o ácido eicosapentaenóico (C20:5 n-3, EPA) e docosahexaenóico (C22:6 n-3, DHA) reduzem a concentração plasmática de triacilgliceróis em humanos. Entretanto, uma alta proporção desses ácidos graxos na dieta poderia favorecer a susceptibilidade das células à peroxidação, aumentando o risco de desenvolvimento de doenças cardiovasculares. Embora modelos animais não sejam recomendados para avaliar o efeito de n-3 PUFA nas lipoproteínas plasmáticas, estes têm sido amplamente utilizados como modelo para avaliação de dano oxidativo. Diferenças nos procedimentos metodológicos também têm gerado dificuldade na comparação de resultados. Desta forma, o objetivo deste estudo foi aplicar os mesmos procedimentos metodológicos para comparar o efeito da suplementação de n-3 PUFA nos biomarcadores plasmáticos de estresse oxidativo utilizando um modelo humano e um modelo animal. Indivíduos foram aleatoriamente distribuídos em dois grupos num delineamento paralelo duplo cego e receberam uma suplementação de 460,0 mg/dia de n-3 PUFA (OMEGA) contendo 240,0 mg de EPA + 160,0 mg de DHA + 60,0 mg de outros n-3 PUFAs, ou óleo de soja (PLACEBO) durante 6 semanas. Ratos Wistar também foram distribuídos em dois grupos e receberam uma dieta contendo 192,5 mg/dia de n-3 PUFA (FO) sendo 116,3 mg de EPA + 61,5 mg de DHA + 14,7 mg de outros n-3 PUFAs ou óleo de soja (SO) durante 3 semanas. Indivíduos do grupo OMEGA apresentaram maior concentração de malondialdeído (MDA) no plasma medido por TBARS quando comparado aos respectivos valores no baseline. A suplementação com n-3 PUFA não alterou a concentração plasmática de α-tocoferol e a atividade antioxidante determinada pelo método DPPH. Apesar dos animais terem recebido doses 10 vezes maiores de n-3 PUFA (2,9 mg/kcal) quando comparadas aos humanos (0,3 mg/kcal) não foram observadas alterações entre os grupos FO e SO para as concentrações de MDA no plasma e no homogenato de cérebro. Em resumo, pode-se sugerir que o modelo animal usado neste estudo parece não ser o mais adequado para avaliar o estresse oxidativo após intervenções dietéticas com n-3 PUFAs em função de diferenças no metabolismo e nos mecanismos de proteção antioxidante observados entre os dois modelos. / Omega-3 polyunsaturated fatty acids (n-3 PUFA) such as eicosapentaenoic (C20:5 n-3, EPA) and docosahexaenoic (C22:6 n-3, DHA) reduce plasma triacylglycerol concentration in humans. However, higher proportion of these fatty acids in the diet could raise cells lipoperoxidation susceptibility, increasing the cardiovascular disease risk. Although animal models are not recommended to evaluate the effect of n-3 PUFA in plasma lipoproteins, they have been widely used as model for oxidative damage. Difference in methodological proceedings has also caused difficulties to compare data among assays. Thus, the objective of this study was to apply the same methodology to investigate the effect of n-3 PUFA supplementation on oxidative biomarkers in animal and human model. Individuals were randomly assigned in two groups in a parallel double blind design and received a supplement of 460.0 mg/day n-3 PUFA (OMEGA) containing 240.0 mg EPA + 160.0 mg DHA + 60.0 mg other n-3 PUFAs, or soybean oil (PLACEBO) during 6 weeks. Wistar rats were also assigned in two groups and received a diet containing 192.5 mg/day n-3 PUFA (FO) containing 116.3 mg EPA + 61.5 mg DHA + 14.7 mg other n-3 PUFAs or soybean oil (SO) for 3 weeks. Individuals in OMEGA group showed higher malondialdehyde (MDA) concentration in plasma measured by TBARS when compared to their baseline values. N-3 PUFA supplementation did not change plasma α-tocopherol concentration and antioxidant activity determined by DPPH method. Although animals have received a 10-fold higher dose of n-3 PUFA (2.9 mg/ kcal) than humans (0.3 mg/kcal), no alteration was observed between FO and SO groups for plasma and brain homogenate MDA concentration. In summary, it can be suggested that the model used in this study doesn\'t seem appropriate to evaluate oxidative stress after dietetic interventions with n-3 PUFA due to physiological differences involved in lipid metabolism and antioxidant protection observed between both models.
|
87 |
Efeito da suplementação dietética com ácidos graxos ômegas 3 e 6 sobre a composição do colostro e leite de éguas e transferência imunitária para os potros / Effect of Dietary Supplementation with Fatty Acids Omegas 3 and 6 on the composition of colostrum and milk of mares and foals for Immune TransferThiago Natal Centini 18 December 2012 (has links)
Com a utilização de 18 éguas, adultas, sem raça definida, com peso médio de 521±56 Kg, em delineamento inteiramente casualisado com três tratamentos e seis repetições por tratamento com medidas repetidas no tempo. Os objetivos deste trabalho foi verificar os efeitos da suplementação dietética com ácidos graxos ômegas 3 e ômega 6 sobre a composição do colostro e leite de éguas e transferência imunitária para os potros. Diferenças significativas encontradas foram na qualidade do leite das éguas onde foi observado efeito de tempo (semanas) sobre as variáveis de gordura, proteína, lactose e sólidos totais. Para a variável sólidos totais observou-se efeito do tratamento, semana e da inclusão de óleo na dieta. Observou-se nos potros uma atividade linfoproliferativa, no grupo óleo de soja semelhante ao encontrado no grupo controle, em ambos os períodos analisados. O grupo óleo de linhaça apresentou atividade linfoproliferativa maior do que a encontrada nos dois outros grupos no dia sete. No dia trinta, o grupo de linhaça continuou a apresentar uma maior atividade proliferativa, no entanto sem diferença estatística. A suplementação fonte de óleo aumentou a energia dietética disponível e a resposta proliferativa das éguas do dia sete. Observou-se que a suplementação com óleo de linhaça promoveu um aumento das concentrações dos isótopos IgGa e IgGb no colostro. A concentração média de IgGa no grupo óleo de linhaça foi quase 4 vezes superior aquela encontrada no colostro das éguas do grupo controle e quase 3 vezes superior aquela encontrada no grupo suplementado com óleo de soja com uma significância de. Assim concluímos que o ômega 3 melhorou a posta linfoproliferativa e aumentou a concentração de IgGb, porem não alterou os componentes do leite. / With the use of 18 mares, adult mongrel with a mean weight of 521 ± 56 kg in completely randomized design with three treatments and six replicates per treatment with repeated measures. The objectives of this study was to determine the effects of dietary supplementation with fatty acids omega 3 and omega 6 on the composition of colostrum and milk of mares and foals for immune transfer. Significant differences were found in milk quality mares where was no effect of time (weeks) on the variables of fat, protein, lactose and total solids. For variable total solids was observed effect of treatment week and oil inclusion in the diet. It was observed in foals lymphoproliferative activity in the soybean oil group similar to that found in the control group in both periods analyzed. The group linseed oil lymphoproliferative showed activity greater than that found in the other two groups on day seven. On the thirtieth day, the flaxseed group continued to show a higher proliferative activity, however no statistical difference. The source of oil supplementation increased dietary energy available and the proliferative response of mares of day seven. It was observed that supplementation with flaxseed oil promoted increases in concentrations of isotopes and IgGa IgGb in colostrum. The average concentration of IgGa group in linseed oil was almost 4 times higher than that found in colostrum of mares in the control group and almost 3 times higher than that found in the group supplemented with soybean oil with a significance. Thus we conclude that omega 3 put lymphoproliferative improved and increased the concentration of Ig, but it does not change the components of milk.
|
88 |
Influência do ω-3 sobre a lipoproteína de baixa densidade eletronegativa [LDL(-)], anticorpos LDL(-) e tamanho das partículas de LDL em indivíduos com síndrome metabólica / Influence of ω-3 over electronegative low density lipoprotein [LDL(-)] plasma concentrations, antiLDL(-) and LDL particles in individuals with metabolic syndromeDiana Gabriela Estevez Fernandez 23 March 2015 (has links)
Introdução A Síndrome Metabólica (SM) representa um conjunto de fatores que determinam maior risco para Doença Cardiovascular (DCV), devido principalmente à Resistência à Insulina (RI) e ao estado inflamatório promovido pelo tecido adiposo branco hipertrofiado. Nesse contexto, a condição de dislipidemia favorece o desenvolvimento da aterosclerose, devido a que maiores concentrações de lipoproteína de baixa densidade (LDL) no plasma podem propiciar modificações nessas partículas. Essas modificações podem ter origem oxidativa ou não oxidativa e impactar nas características aterogênicas da LDL. O ômega três tem mostrado efeitos hipolipemiantes e anti-inflamatórios, que podem reduzir o risco cardiovascular de indivíduos com SM. Objetivo:: avaliar o efeito da suplementação de 3g de ω-3 por um período de oito semanas sobre a concentração plasmática das partículas de LDL eletronegativas [LDL(-)] e seus anticorpos, assim como monitorar possíveis mudanças nas concentrações das subfrações das LDL. Metodologia: Foram incluídos 115 participantes de ambos os sexos, entre 30 e 74 anos, com SM, separados nos grupos de intervenção com ω-3 (n=58) e controle com ω-9 (n=57). Foram realizadas análises de perfil lipídico e por meio de ELISA foram avaliadas a concentração de LDL(-) e de antiLDL(-) no plasma dos participantes. O tamanho das subfrações de LDL foi realizado no sistema Lipoprint. O efeito do tempo e das intervenções foi testado por meio do programa SPSS versão 20.0, adotando-se o concentração de significância de p<0,05. Resultados: A suplementação de ω-3 teve efeito significativo na redução do % de massa grassa (%MG) e na pressão arterial sistólica (4%) e diastólica (5%). Em relação ao perfil lipídico, ambas intervenções tiveram efeitos significativos de redução de colesterol total (CT), LDL-c, não HDL (nHDL) e triacilglicerois (TG). As concentrações plasmáticas de LDL(-) dos participantes que tomaram ômega 3 apresentaram redução de 21%, enquanto que os que tomaram ômega 9 tiveram redução de 1%. Tal redução foi significativa em relação ao tempo de intervenção (p<0,05), mas não quando o efeito da internveção foi avaliado. Perfil semelhante foi observado para a razão LDL(-)/antiLDL(-), observou-se redução de 22% no grupo ômega 3 e redução de somente 3% no grupo ômega 9. Conclusão: A intervenção com ômega 3 promoveu redução na concentração plasmática de LDL(-), porém não modificou a concentração do anticorpo antiLDL(-) nem o tamanho das subfrações da LDL. / Introduction: The Metabolic Syndrome (MetS) is a combination of factors that determine increased risk for Cardiovascular Diseases (CVD), mainly because of Insulin Resistance (IR) and the inflammatory state promoted by the hypertrophied white adipose tissue. Under this background, the dyslipidemic condition goes together with the developing of atherosclerosis, meaning that higher concentrations of low density lipoprotein (LDL) in plasma promote modifications from different sources in these particles and may have an impact over LDL subfractions, turning them more atherogenic. Omega three has proved hypolipidemic and anti-inflammatory effects, which may reduce cardiovascular risk in MetS individuals. Objetive: evaluate the effect of 3g of fish oil supplementation, 60% EPA and DHA during an eight week period over plasma concentrations of electronegative LDL particles [LDL(-)] and its antibodies, as well as monitoring possible changes in LDL subfractions. Methods: A total number of 115 participants, both sexes, between 30 and 74 years of age, with MetS, were included and separated in the intervention group receiving omega 3 (n=58) and the placebo group with omega 9 (n=57). Biochemical analyses were carried out using ELISA for LDL(-) and antiLDL(-) in plasma. Particle sizes were measured using the Lipoprint system. The effects of time and intervention were analyzed using the statistical program SPSS 20.0, assuming p<0.05 as significant. Results: Omega 3 supplementation had a significant effect in the reduction of fat mass percentage (FM%) and blood pressure, showing a 4% decrease for systolic and 5% decrease for diastolic pressures respectively. Considering the lipid profile, both interventions had significant effects reducing total cholesterol (TC), LDL-c, not HDL (nHDL) and tryacylglycerides (TG). LDL(-) plasma concentrations from the omega 3 group showed 21% reduction while the omega 9 group had only 1% reduction. Such difference was significant considering time (p<0,05), but not while comparing the intervention effect. There was also a change in the antiLDL(-) antibodies; reducing 2% in the omega 3 group and increasing 1% in the omega 9 group. However, those differences were not significant. Similar effects were observed in LDL(-)/antiLDL(-) ratio, showing 22% decrease in the omega 3 group and only 3% in the omega 9 group. Conclusion: Omega 3 intervention promoted a significant reduction in plasmatic LDL(-), however, it didn\'t modify LDL subfraction distribution.
|
89 |
Rôle des acides gras polyinsaturés alimentaires dans l'homéostasie lipidique de la rétine en conditions physiologiques et pathologiques liées au vieillissement / Role of dietary polyunsaturated fatty acids in the retina lipid homeostasia in physiological and pathological conditions associted with agingThierry, Magalie 19 November 2014 (has links)
La rétine est constituée de l’association d’un tissu neurosensoriel et de l’épithélium pigmentaire rétinien (EPR). Malgré la présence d’une barrière hémato-rétinienne, la rétine est contrainte aux changements de son milieu environnant, incluant les modifications du régime alimentaire et les stress environnementaux. Au cours du vieillissement, les échanges de nutriments et l’élimination des déchets métaboliques et cellulaires au travers de l’EPR diminuent. La dégénérescence maculaire liée à l’âge (DMLA) et la rétinopathie diabétique (RD) sont les pathologies rétiniennes les plus prévalentes dans les populations occidentales avant et après l’âge de 50 ans, respectivement. L’atrophie géographique et la DMLA néovasculaire constituent les stades avancés des maculopathies liées à l’âge. La RD affecte 60% des patients atteints de diabète de type 2 (T2D) dans les 15 années suivant l’apparition de la pathologie. Par ailleurs, les facteurs alimentaires interfèrent avec le développement de la DMLA et du T2D. Considérant l’épidémie mondiale de T2D d’une part, et l’allongement de l’espérance de vie d’autre part, les dépenses médico-sociales relatives à la prise en charge des patients atteints de T2D ou de DMLA sont à même de devenir un enjeu socioéconomique majeur. Le syndrome métabolique (SMet) est un des principaux facteurs de risque du T2D. Il peut ainsi être suggéré que limiter le développement du SMet pourrait potentiellement limiter l’incidence du T2D et de ses complications. Dans ce contexte, la consommation d’acides gras polyinsaturés à longue chaîne (AGPI-LC) de type oméga 3 fait partie des recommandations nutritionnelles pour la population afin de prévenir l’apparition du SMet et du T2D. Par ailleurs, une alimentation riche en AGPI-LC omega-3 est également associée à la réduction du risque de DMLA. En revanche, l’association entre T2D, RD et DMLA reste controversée, bien que quelques études basées sur des grandes cohortes rapportent une prévalence de DMLA augmentée chez les patients atteints de diabète ou de RD. Nos objectifs ont été d’évaluer premièrement si un SMet constituait un environnement favorable au développement des complications de type néovasculaires dans la rétine, et de tester secondairement l’efficacité d’AGPI-LC omega-3 dans la réduction des conséquences de ce SMet sur la rétine. Pour atteindre cet objectif, des rats ont été nourris avec un régime diabétogène enrichi en fructose afin de provoquer un SMet. Une néovascularisation choroïdienne a ensuite été induite en utilisant un modèle d’impacts laser au fond d’œil. Nous nous sommes intéressés tout d’abord à l’effet de ce régime à court terme et avons mis en évidence une diminution de la sensibilité des photorécepteurs de type cônes après 8 jours de régime, ainsi qu’une modification de l’expression des gènes et en particulier des sous-familles de cristallines. Ensuite, nos études se sont portées sur les effets de régime enrichi en fructose à long terme jusqu’à 6 mois. Le développement d’un SMet a été illustré par une augmentation de la masse grasse, une hyperinsulinémie, une hyperleptinémie et l’installation d’une stéatose hépatique. Ces rats ont développé une néovascularisation choroïdienne exacerbée après 1 et 3 mois de régime associée à une surexpression de facteurs pro-angiogéniques tels que VEGF et leptine .Une infiltration de macrophages dans la rétine et/ou l’activation des cellules microgliales résidentes a également été détectée. Les données électrorétinographiques ont suggéré une diminution de la sensibilité des photorécepteurs de type bâtonnets ainsi qu’une altération des fonctionnalités des cellules de la rétine interne à 6 mois. Dans un second temps, l’efficacité des AGPI-LC omega-3 (EPA+DHA) dans le but de réduire les conséquences du SMet dans la rétine a été testée. Nos données mettent en évidence qu’une forte dose d’EPA+DHA n’a cependant pas amélioré le SMet chez le rat. / The retina is the association of the neurosensory tissue and the retinal pigment epithelium (RPE). Despite the presence of the blood retinal barrier, the retina is submitted to changes of the external milieu, including dietary modulation and environmental stresses. With advanced age, the exchanges of nutrients and elimination of cellular and metabolic wastes via the RPE become limited. Age-related Macular Degeneration (AMD) and Diabetic Retinopathy (DR) are the most prevalent retinal pathologies in Western adult populations before and after the age of 50 years, respectively. Geographic atrophy and neovascular AMD are advanced stages of age-related maculopathies. DR afflicts 60% of type 2 diabetic (T2D) patients in the first 15 years of the disease. Dietary factors interfere in the development of both AMD and T2D. Accounting the worldwide epidemics of T2D in the one hand, and the improvement of life expectancy in the other hand, medical care to the patients is expected to worsen the socioeconomic burden of both T2D and AMD. Metabolic syndrome (MetS) is one of the major risk factor for T2D. Lowering the development of MetS would potentially lessen the incidence of T2D, and its complications. The daily intake of omega 3 long chain polyunsaturated fatty acids (LC-PUFA) is now recommended by health agencies for the prevention of MetS. Meanwhile dietary omega 3 LC-PUFA are associated with reduced risk of AMD. The association between T2D, DR, and AMD remains controversial, although large-scale population-based studies have reported increased prevalence of AMD in patients with diabetes or DR. Our objectives were first to evaluate whether MetS would represent a favorable environment for the development of neovascular complications in the retina, and second to test the efficacy of omega 3 LC-PUFA to reduce the consequences of MetS in the retina. For that purpose, a pro-diabetogenic high fructose diet was fed to rats to induce MetS and choroidal neovascularization was triggered by laser impacts in the eye fundus. We focused first on short term diet periods, and showed impairment on cone photoreceptor sensitivity after 8 days, as well as changes in gene expression in relation to crystallin sub-families. A long term - up to 6 months - fructose diet period triggered MetS as illustrated by body fat increase, hyperinsulinemia, hyperleptinemia and liver steatosis. Rats exhibited exacerbated laser-induced choroidal neovascularization after 1 and 3 months of feeding, that was associated with up-regulation of genes coding pro-angiogenic factors such as VEGF and leptin, as well as infiltration of macrophages and/or activation of retinal microglia. Electroretinographic data showed decreased sensitivity of rod photoreceptors and inner retinal cell functionality at 6 months of feeding. In a second time, the efficacy of dietary omega 3 LC-PUFA (EPA plus DHA) to reduce the consequences of MetS in the retina was tested. Our data showed that a high dose of EPA+DHA in rats did not improve MetS. Furthermore, side effects were generated as illustrated by localized atrophy in the retina submitted to the combination of laser-impacts, and normal light exposure. These works allowed us to suggest that MetS generated a favorable environment in the retina for the development of neovascular complications. Meanwhile, the sensitivity of cones and rods was impaired by MetS. Accounting the deleterious long term effects of omega 3 LC-PUFA in the retina, caution may be taken while recommending massive supplementation with omega 3 LC-PUFA in the context of MetS.
|
90 |
Diagnostka firmy Omega Optix, s.r.o. se zaměřením na analýzu mezinárodních vztahůNováková, Zuzana January 2009 (has links)
Cílem diplomové práce je posoudit finanční zdraví společnosti Omega Optix, s.r.o. a zhodnotit její postavení jak na českém trhu, tak na trzích zahraničních. Jejím jádrem je finanční analýza doplněná o strategickou analýzu a v praktické části o analýzu mezinárodních vztahů. Teoretická část je zaměřena na metody finanční analýzy. Obsahuje horizontální a vertikální analýzu rozvahy a výkazu zisku a ztráty, dále analýzu rozdílových a poměrových ukazatelů, bilanční pravidla a souhrnné modely hodnocení podniku. V praktické části jsou jednotlivé metody finanční analýzy aplikovány na společnost Omega Optix, s.r.o. v letech 2004-2008. Strategická analýza doplňuje finanční informace o charakteristiku makrookolí a mikrookolí podniku. Samostatnou kapitolou je analýza mezinárodních vztahů. Výsledkem provedených analýz je SWOT analýza společnosti Omega Optix a z ní plynoucí závěrečná doporučení.
|
Page generated in 0.0421 seconds