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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.
521

Efeito da suplementação de β-caroteno sintético no DNA e no metabolismo de células hepáticas de ratos recebendo etanol / Effect of synthetic (β-carotene supplementattion in the DNA and metabolism of hepatic cells of rats receiving ethanol

Marcia Elena Zanuto 03 May 2005 (has links)
A suplementação de &#946;-caroteno em fumantes e alcoólatras pode promover efeitos indesejáveis, manifestando a característica pró-oxidante deste carotenóide. Sabendo que o fígado é o principal órgão de armazenamento de vitamina A e (&#946;-caroteno, e local de oxidação do etanol, o presente estudo buscou investigar no fígado de ratos, a influência da suplementação de (&#946;-caroteno isolado ou associado ao etanol, sobre o metabolismo celular, danos no DNA, proliferação celular e função da proteína p53. Os ratos receberam dietas líquidas contendo (&#946;-caroteno (24mg/L dieta) com (GAB) ou sem (GBC) a adição de etanol (36% da calorias totais da dieta) e dieta líquida normal (isenta de &#946;-caroteno e etanol) (GDN), durante seis semanas de período experimental. Após este período, os animais foram sacrificados para determinações hepáticas e plasmáticas de (&#946;-caroteno, retinol, palmitato de retinila, presença de esteatose, determinações hepáticas de SRATB e GSH, danos no DNA de hepatócitos e expressão do PCNA e da proteína p53. Os resultados mostraram diferenças (p<0,05) entre os grupos quanto as concentrações hepáticas de retinol (&#181;g/g) (GAB: 2,49 ± 0,25; GBC: 4,22 ± 0,24; GDN: 2,83 ± 0,21) e palmitato de retinila (&#181;g/g) (GAB: 40,87 ± 3,98; GBC: 83,72 ± 6,00; GDN: 46,33 ± 3,60), concentração plasmática de retinol (llmol/L) (GAB: 1,42 ± 0,12; GBC: 0,69 ± 0,06; GDN: 2,37 ± 0,28), presença de esteatose (GAB: 2,30 ± 0,21; GBC: 1,00 ± 0,00; GDN: 1,00 ± 0,00), danos no DNA de hepatócitos (danos DNA/100 hepatócitos) (GAB: 285,90 ± 15,20; GBC: 273,83 ± 13,39; GDN: 138,00 ± 4,04) e expressão do PCNA (%0) (GAB: 7,12 ± 1,46; GBC: 1,47 ± 0,27; GDN: 2,04 ± 0,31). As concentrações hepáticas e plasmáticas de &#946;-caroteno, SRATB e GSH hepáticos, não apresentaram diferença (p>0,05) entre os grupos. A proteína p53 não foi expressa em nenhum dos grupos estudados. Estes resultados mostraram que o (&#946;-caroteno isolado e em associação com o etanol não influenciaram na peroxidação lipídica e na expressão da proteína p53. A associação &#946;-caroteno + etanol foi mais prejudicial ao fígado, promovendo alterações no metabolismo celular dos hepatócitos, esteatose, danos no DNA e proliferação celular, considerando que o &#946;-caroteno isolado foi genotóxico ao hepatócito. / &#946;-carotene, when supplemented in smokers and alcohol drinkers may act as prooxidant, resulting in undesirable effects. The liver is the &#946;-carotene and vitamin A main storage organ and where ethanol oxidation takes place. This study investigated in rats\' liver, the influence of &#946;-carotene supplementation either alone or associated with ethanol in cellular metabolism, DNA damage, cellular proliferation and p53 protein function. Three groups of 12 rats received liquid diets containing &#946;-carotene (24mg/L diet) with (BAG) or without (CBG) ethanol (36% of total energy intake). Control animals received liquid diet free of ethanol and &#946;-carotene (NDG). After 6 weeks the animals were sacrificed for hepatic and plasma concentrations of &#946;-carotene, retinol, palmitate retinyl, steatosis, GSH and TBARS, DNA damage, PCNA and p53 expression were evaluated in the liver. Differences were significant for hepatic (BAG: 2.49 ± 0.25; CBG: 4.22 ± 0.24; NDG: 2.83 ± 0.21 mg/g) and plasmatic (BAG: 1.42 ± 0.12; CBG: 0.69 ± 0.06; NDG: 2,37 ± 0,28mmol/L) retinol and hepatic palmitate retinyl (BAG: 40.87 ± 3.98; CBG: 83.72 ± 6.00; NDG: 46.33 ± 3.60), steatosis (BAG: 2.30 ± 0.21; CBG: 1.00 ± 0.00; NDG: 1.00 ± 0.00), DNA damage (BAG: 285.90 ± 15.20; CBG: 273.83 ± 13.39; NDG: 138.00 ±4.04 DNA damages/100 hepatocytes) and PCNA expression (BAG: 7.12 ± 1.46; CBG: 1.47 ± 0.27; NDG: 2.04 ± 0.31) among the groups (p<0.05). Hepatic and plasmatic concentrations of &#946;carotene, TBARS and GSH were not statistically different. p53 staining was not detected in any group. This suggests that &#946;-carotene alone or with ethanol association does not influence lipid peroxidation and p53 expression. &#946;-carotene+ethanol caused metabolic alteration, steatosis, DNA damage and cellular proliferation in hepatocytes. Furthermore, supplementation with &#946;-carotene alone had genotoxic effects in the liver.
522

Efeito da suplementação com castanha-do-brasil (Bertholletia excelsa, H.B.K.) no estado nutricional de praticantes de capoeira em relação ao selênio / Effect of supplementation with Brazilian nuts (Bertholletia excelsa, H.B.K.) in the nutritional status of Selenium and it\'s activity in young adult capoeira players

Vanessa Fernandes Coutinho 10 September 2003 (has links)
O objetivo deste estudo foi estabelecer uma correlação entre o efeito da suplementação por meio da ingestão de castanhas-do-brasil (CS) com o estado nutricional de praticantes de capoeira em relação ao selênio (Se). A importância deste micronutriente foi evidenciada pela sua participação no sistema de proteção antioxidante, justificada pela incorporação de Se na glutationa peroxidase (E. C. 1.11.1.9). Esta enzima catalisa a redução de hidroperóxidos e facilita a conversão de H2O2, protegendo o organismo contra o dano oxidativo, e outros efeitos prejudiciais das espécies reativas de oxigênio (ROS). A atividade física proporciona um aumento no consumo de O2 e consequentemente maior produção de ROS, provocando estresse oxidativo. A pesquisa foi composta por 29 capoeiristas, residentes em São Paulo, com idade média de 21 anos para mulheres, e 24 para homens. O período médio de treinamento foi de 3,51 por semana e a duração de cada treinamento em média, foi de 109 minutes. O consumo médio de oxigênio (VO2 Máx.) foi de 41 ml/kg/min para as mulheres, e 48mllkg/min para os homens. A classificação do estado nutricional dos capoeiristas, de acordo com seu IMC foi normal (Organização Mundial de Saúde, 1995). Antes da suplementação, a ingestão usual de Se dos capoeiristas foi insatisfatória de acordo com a EAR e RDA. A concentração de Se no plasma e eritrócito aumentou depois da suplementação com CS (p<0,05), mas não houve correlação com o sexo dos participantes. A atividade enzimática da GPx também aumentou após a suplementação (p<0,05), demonstrando que a enzima é um sensível indicador do estado nutricional de Se, e não houve correlação em relação ao sexo dos participantes. Os resultados sugerem uma correlação positiva entre o efeito da suplementacão com CS e a concentração de Se e da atividade da enzima GPx (p< 0,05; R=0,72 para o plasma and R=85 para o eritrócito). / The purpose of this study was to establish a correlation between the effect of supplementation with Brazilian nuts (BN) with the nutritional status of Se and it\'s activity in young adult capoeira players. The biological importance of this oligoelement was evident by the participation in the \"antioxidant protection system\". It\'s antioxidant role is justified by its incorporation, as selenium, in the peroxidase glutathione (E.C. 1.11.1.9). This enzyme catalyzes the reduction of organic hidroperoxides and facilitates the conversion of H2O2 protecting the organism against the oxidative damage, and other harmful effects of \"reactive oxygen species\" (ROS). The physical activity causes an increase in consumption of O2 and consequently high production of ROS, causing oxidative stress. The population has composed of 29 capoeira players resident in São Paulo, with a mean age of 21 women and 24 for men. The average training period was 3,51 per week and the duration of each training period was 109,46 minutes. The average oxygen consumption (VO2 Máx., ml/kg/min) was 41 for women and 48 for men. Nutritional status classification of the capoeira players (cap) according with World Health Organization (WHO): IMC (1995) was normal. Before supplementation the usual diet was unsatisfactory for selenium according to EAR and RDA (2000). The Se concentration of the plasma and erythrocyte increased after supplementation with Brazilian nuts (p< 0,05), but didn\'t correlated with the sex of the participants. GSH-Px enzymatic activity also increased after this supplementation (p< 0,05), showing that this enzyme is a sensitive marker of nutritional status of Se. Also we didn\'t found correlation with the sex of the participants. The results suggest a positive correlation between the effect of supplementation with BN and Se concentrations and the activity of the GSH-Px enzyme (p< 0,05; R=0,72 for the plasma and R=85 for the erythrocyte).
523

La supplémentation périnatale en fibres prébiotiques (fructo-oligosaccharides à courte chaîne, scFOS) modifie le microbiote intestinal et programme le phénotype métabolique et immunitaire du porc, pris comme modèle de l’Homme / Perinatal supplementation with prebiotic fibres (short-chain fructooligosaccharides, scFOS) modifies intestinal microbiota and programs the metabolic and immunologic phenotype in the pig, used as human model

Le Bourgot, Cindy 10 November 2016 (has links)
La nutrition périnatale conditionne durablement les fonctions physiologiques, avec des conséquences sur la susceptibilité à développer des maladies métaboliques à l’âge adulte. Le microbiote représente un des acteurs de cette empreinte nutritionnelle. L’objectif est de déterminer chez le porc l’impact d’une supplémentation périnatale en fructo-oligosaccharides à courte chaîne (scFOS) sur le développement des fonctions immunitaires et endocrines intestinales et les conséquences sur la santé métabolique de l’adulte en situation de déséquilibre nutritionnel.La supplémentation maternelle en scFOS, en modifiant le microbiote de la mère et de la descendance et la qualité du lait, accélère la maturation du système immunitaire intestinal des porcelets allaités.La fenêtre d’exposition (maternelle vs post-sevrage) conditionne la nature des modifications immunes induites par les scFOS. La supplémentation périnatale en scFOS modifie la réponse métabolique de l’adulte à un régime déséquilibré en stimulant la fonction endocrine intestinale et la sensibilité du pancréas au glucose, en réduisant les risques d’inflammation, et en modifiant l’homéostasie métabolique, associé à des modulations du microbiote.En résumé, la consommation périnatale de prébiotiques programme le phénotype métabolique et immunitaire de l’adulte via des modulations persistantes du microbiote. L'approche intégrée des données a permis d’identifier des acteurs moléculaires impliqués dans l’adaptation différentielle des individus à un régime déséquilibré en fonction de leur alimentation périnatale. / Perinatal scFOS supplementation modifies metabolic response to an unbalanced diet in adults by stimulating intestinal endocrine function and pancreas sensitivity to glucose, by reducing risks of inflammation, and in fine by changing metabolic homeostasis in association with modifications of microbiota.In summary, prebiotic consumption during perinatal life programs the immune and metabolic phenotype of adults through persistent modulations of intestinal microbiota. The integrated approach of data enables us to identify molecular actors involved in the differential adaptation of individuals to an unbalanced diet according to their perinatal nutrition.
524

Tvorba biofilmu u probiotických kultur a možnosti jeho využití ve farmacii / Biofilm formation in probiotic cultures and its application in pharmacy

Ryšávka, Petr January 2021 (has links)
The work was comprehensively focused on the development of adhesive forms of probiotics in the form of a biofilm on combined carriers with a prebiotic component. The second part dealed with the influence of food on the multiplication and survival of selected types of probiotic bacteria. Subsequently, the effect of individualized probiotic supplements on changes in the human intestinal microbiome was monitored. Suitable adherent probiotic strains for biofilm formation were selected and tested. Methods have been introduced and different variants of carriers for culturing and binding bacteria have been tested. In vitro experiments verified the stability of biofilm stucture and its resistance to low pH, bile and antibiotics in comparison with the planktonic cell form. The antimicrobial effect of probiotic strains in the form of a biofilm was studied. The cultivation of the multispecies biofilm on the combined carrier was optimized and the stability of the biofilm and the final viability of probiotic bacteria were confirmed. Furthermore, the influence of various foods and beverages on the viability of probiotic bacteria was evaluated with emphasis on the simulation of passage through the gastrointestinal tract. Both models, solutions with standardised concentrations of alcohol, sugar, salts, proteins or different pH and different types of real foods and beverages were tested. The effect of food and beverages was tested on monocultures of Lactobacillus acidophilus, Bifidobacterium breve and on probiotic capsules containing a mixed culture of probiotic microorganisms. The survival of probiotics in various food matrices in the simulated gastrointestinal tract was quantitatively different. We managed to define foods suitable for supporting the multiplication of probiotic bacteria. A separate part of the work was focused on the targeted modulation of the intestinal microbiome by individualized probiotics that were prepared on the basis of molecular biological analyzes of the intestinal microbiome aimed at detecting the percentage of lactobacilli, bifidobacteria and phylum Firmicutes and Bacteroidetes. Personalized probiotic supplementation confirmed the positive effect of this approach on microbiome changes, especially on the increase of the content of lactobacilli, bifidobacteria and the overall diversity of the microbiome.
525

Six weeks of high intensity interval training with hyperoxia or normoxia in trained cyclists : A polarized and periodized training approach / Sex veckors högintensiv intervallträning med hyperoxi eller normoxi för tränade cyklister : En polariserad och periodiserad träningsmodell

Manselin, Tom, Södergård, Olof January 2015 (has links)
Aim The main aim of this study was to investigate the longitudinal effects on cycling performance using a polarized and periodized scheme that was highly supervised and controlled. The second aim was to investigate the effect of using Hyperoxia. The questions used to address the aim were: (1) How does overall performance change after a six-week training intervention? (2) What is the time-course and pattern of performance changes to the training scheme? (3) How does the performance change within the groups?   Method Nineteen male and female cyclists started the study (13 male and 6 female), however only 12 completed it (8 male and 4 female). The characteristics for the 12 subjects were:  age (year) 33.6 ± 6.8, height (cm) 177 ± 9.1, body mass (kg) 73.4 ± 8.8. Using a randomized, double blind design, the test subjects were divided in to hyperoxia (HOT) (n = 6) and normoxia (NOT) (n = 6) training groups.  Over a six week period the subjects followed a controlled polarized periodization that included 15 high intensity interval training (HIIT) sessions (3 x 8 min, 3 x 8 + 4 min, 4 x 8 min &amp; 4 x 4 min) on maximal sustainable intensity (isoeffort) on a cycle ergometer. The dosage of oxygen was administered intermittently by the oxelerate device. A 20 min all out test was performed as pre- and post test.    Results The whole group (n = 12) increased mean power output (W) by 6.4 % (P = 0.002). The relative power output (W/kg) increased significantly 8.2 % (P = 0.0011). The HOT group (n = 6) increased their power output by 8.3 % (P = 0.028) and their relative power output increased by 9.4 % (P=0.011). The whole group (P = 12) significantly increased their VO2mean by 4.1 % (P = 0.03) and in the relative value by 5.4 % (P = 0.01) on the 20 min all out test. The whole group also had a significant increase in VO2peak of 3.7 % (P = 0.04). A very strong correlation could be found between the training data and the performance test.   Conclusions The training intervention was favourable for increasing performance and VO2peak in cycling. Usage of hyperoxia during the training intervention increases the performance. / Syfte och frågeställningar Huvudsyftet med denna studie var att undersöka de longitudinella effekter på prestation i cykling med hjälp av ett polariserat och periodiserat träningsupplägg som var väl övervakat och kontrollerat. Det andra syftet var att undersöka effekten av att använda hyperoxi. De frågeställningar som hjälpte att besvara syftet var: (1) Hur förändras prestationen efter en sex veckors träningsintervention? (2) Hur anpassar sig försökspersonerna till träningsschemat över tid?  (3) Hur förändras prestationen inom grupperna?   Metod 19 manliga och kvinnliga cyklister deltog i studien (13 manliga och 6 kvinnliga), 12 fullföljde hela studien (8 manliga och 4 kvinnliga). Karaktäristiken för de 12 försökspersonerna var: ålder (år) 33.6 ± 6.8, längd (cm) 177 ± 9.1, vikt (kg) 73.4 ± 8.8. Försökspersonerna delades in i hyperoxi (HOT) (n = 6) och normoxi (NOT) (n = 6), studien var dubbelblind. Under sex veckor följde försökspersonerna en kontrollerad polariserad periodisering som inkluderade 15 högintensiva intervallträningspass (HIIT) (3 x 8 min, 3 x 8 + 4 min, 4 x 8 min &amp; 4 x 4 min) på högsta genomförbara intensitet (isoeffort) på cykelergometer. Doseringen av syre administrerades intermittent genom Oxelerate-enheten. Ett 20 min all-out test utfördes som för- och eftertest.   Resultat Hela gruppen (n = 12) ökade signifikant på prestationstestet (W) med 6.4 % (P = 0.002). Den relativa effekten (W/kg) ökade signifikant med 8.2% (P = 0.0011). HOT (n = 6) ökade signifikant på prestationstestet med 8.3% (P = 0.028) och den relativa effekten ökade med 9.4% (P = 0.011). Hela gruppen (n = 12) ökade signifikant i VO2medel under prestationstestet med 4.1 % (P = 0.03) och i det relativa värdet med 5.4 % (P = 0.01). Hela gruppen hade också en signifikant ökning av VO2peak med 3.7 % (P = 0.04). En mycket stark korrelation hittades mellan träningspassdata och prestationstestet.   Slutsats Träningsupplägget är gynnsamt för ökning av prestation och VO2peak i cykling. Användning av hyperoxi under träningsupplägget ökar prestationen.

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