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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.
41

Papel da geração de oxaloacetato no exercício físico moderado em ratos: consequências da suplementação de aspartato, asparagina e carnitina / Importance of oxaloacetate synthesis on endurance exercise rats: effects of aspartate, asparagine and carnitine supplementation

Lancha Junior, Antonio Herbert 05 November 1993 (has links)
A importância na geração de oxaloacetato foi investigada através da determinação da atividade da piruvato carboxilase nos músculos estriados e da suplementação de seus precursores (aspartato e asparagina) na dieta de ratos. A atividade da piruvato carboxilase eleva-se durante o exercício físico e, portanto, deve fornecer mais oxaloacetato para a etapa inicial do ciclo de Krebs. A suplementação crônica (5 semanas) de aspartato e asparagina promove aumento da resistência ao esforço em ratos treinados em natação durante 1 hora diária por 5 semanas. Este efeito foi acompanhado de elevação no número e tamanho das mitocôndrias e alteração no metabolismo de glicose dos músculos esqueléticos (elevação do conteúdo de glicogênio e de sua síntese e diminuição da glicólise). Esses resultados sugerem que a geração de oxaloacetato desempenha papel fundamental na manutenção do esforço prolongado. A suplementação de aspartato e asparagina na dieta melhora a performance nessas condições, porém causa lesões na ultraestrutura muscular (mitocôndrias, linha \"Z\" e miofibrilas). / The importance of oxaloacetate formation was investigated by measuring pyruvate carboxylase activity in muscles and by given its precursors (aspartate, asparagine) in the diet of rats. The activity of pyruvate carboxylase markedly raised during physical effort and so might provide oxaloacetate for Krebs cycle functioning. The supplementation of aspartate and aspagine for a prolonged period of time (5 weeks) promotes increment in the resistance to exercise in rats trained to swimming during 1 hour daily for 5 weeks. This effect is accompanied by an increase in the size and number of mitochondria and also changes in glucose metabolism; elevation in glycogen synthesis and content and reduction in the rate of glycolysis. These results suggest that the production of oxaloacetate plays a role to maintain the moderate exercise during a prolonged period of time. Nevertheless, the aspartate and asparagine supplemented in the diet, despite improving the perfomance to moderate and prolonged exercise, provokes muscle ultraestructure lesions of mitochondria, \"Z\" line and miofibrils.
42

Resistência ao esforço físico: efeito da suplementação nutricional de carnitina, aspartato e asparagina / Exercise tolerance: effect of aspartate, asparagine and carnitine supplementated in the diet

Lancha Junior, Antonio Herbert 14 March 1991 (has links)
Não Consta Resumo na Publicação / Abstracts Not Available
43

Carnitinemia em pacientes oncológicos / Carnitine in cancer patients

Estela Iraci Rabito 29 October 2007 (has links)
A subnutrição é uma das comorbidades mais freqüentes que atinge os pacientes oncológicos. Entender as conseqüências do câncer nas alterações do metabolismo energético é necessário para o estabelecimento de estratégias que previnam o desenvolvimento e tratem a má-nutrição. A carnitina desempenha papel fundamental no metabolismo energético lipídico. Sendo que o objetivo deste estudo foi avaliar os níveis plasmáticos nos pacientes com câncer no pré cirúrgico e relacionar com os resultados da história alimentar, antropometria, impedância bioelétrica, calorimetria indireta, aminoacidemia e valores urinários de carnitina e nitrogênio. Trata-se de um trabalho prospectivo no qual foram escolhidos aleatoriamente 4 grupos, sendo um de pacientes portadores de câncer esofágico ou gástrico (n=24), e os outros 3 considerados controles. O primeiro grupo controle foi o obesos (n=16), o segundo de voluntários saudáveis (n=12), enterectomizados (n=6) Os valores médios de carnitinemia , em todos os grupos, variou entre 60 e 80 µM no plasma e urinária entre 78 e 124 µM, sem diferenças estatísticas entre os grupos. Quando avaliados os níveis de carnitina plasmático, 80% (p<0.05) dos pacientes com câncer apresentaram deficiência associados à excreção urinária inferior a 5 mol/kg/dia, consumo insuficiente de proteínas e baixa reserva adiposa. No entanto os níveis de metionina e lisina, bem como o gasto energético de repouso não apresentaram diferença com os controles. A deficiência de carnitina nestes pacientes pode comprometer o metabolismo energético além de estar associado à ocorrência de fadiga e piora da qualidade de vida. / The malnutrition is one most common comorbidity among hospitalized patients. Understanding cancer consequences in energetic metabolim changes is necessary in order to avoid malnutrition or to treat it. Carnitine has a important role in lipid metabolism. The aim of this study was to evaluate the levels of serum carnitine in patients with stomach and esophagus cancer and correlated with dietary intake, body composition, resting energy expenditure, carnitine and amino acid serum levels and urinary excretion of carnitine. Twenty-four cancer patients were assessed. Cancer patients were compared with obese (n=16), healthful (n=12) and short bowel disease (n=6). The mean values of serum carnitine and urinary carnitine among all groups were 60-80 µM and 74-124 µM respectively. Serum carnitine levels between cancer patients and other groups were significantly different. 80% of cancer patients had low serum levels, which was associated with urinary below 5 µmol/Kg/day, decreased protein and low adipose tissue. However, the methionine and lysine levels, as well as the resting energy expenditure had no difference when compared with the healthy volunteers. Carnitine deficiency in cancer patients can affect energetic metabolism and contribute to the progression of cachexia.
44

Resistência ao esforço físico: efeito da suplementação nutricional de carnitina, aspartato e asparagina / Exercise tolerance: effect of aspartate, asparagine and carnitine supplementated in the diet

Antonio Herbert Lancha Junior 14 March 1991 (has links)
Não Consta Resumo na Publicação / Abstracts Not Available
45

Papel da geração de oxaloacetato no exercício físico moderado em ratos: consequências da suplementação de aspartato, asparagina e carnitina / Importance of oxaloacetate synthesis on endurance exercise rats: effects of aspartate, asparagine and carnitine supplementation

Antonio Herbert Lancha Junior 05 November 1993 (has links)
A importância na geração de oxaloacetato foi investigada através da determinação da atividade da piruvato carboxilase nos músculos estriados e da suplementação de seus precursores (aspartato e asparagina) na dieta de ratos. A atividade da piruvato carboxilase eleva-se durante o exercício físico e, portanto, deve fornecer mais oxaloacetato para a etapa inicial do ciclo de Krebs. A suplementação crônica (5 semanas) de aspartato e asparagina promove aumento da resistência ao esforço em ratos treinados em natação durante 1 hora diária por 5 semanas. Este efeito foi acompanhado de elevação no número e tamanho das mitocôndrias e alteração no metabolismo de glicose dos músculos esqueléticos (elevação do conteúdo de glicogênio e de sua síntese e diminuição da glicólise). Esses resultados sugerem que a geração de oxaloacetato desempenha papel fundamental na manutenção do esforço prolongado. A suplementação de aspartato e asparagina na dieta melhora a performance nessas condições, porém causa lesões na ultraestrutura muscular (mitocôndrias, linha \"Z\" e miofibrilas). / The importance of oxaloacetate formation was investigated by measuring pyruvate carboxylase activity in muscles and by given its precursors (aspartate, asparagine) in the diet of rats. The activity of pyruvate carboxylase markedly raised during physical effort and so might provide oxaloacetate for Krebs cycle functioning. The supplementation of aspartate and aspagine for a prolonged period of time (5 weeks) promotes increment in the resistance to exercise in rats trained to swimming during 1 hour daily for 5 weeks. This effect is accompanied by an increase in the size and number of mitochondria and also changes in glucose metabolism; elevation in glycogen synthesis and content and reduction in the rate of glycolysis. These results suggest that the production of oxaloacetate plays a role to maintain the moderate exercise during a prolonged period of time. Nevertheless, the aspartate and asparagine supplemented in the diet, despite improving the perfomance to moderate and prolonged exercise, provokes muscle ultraestructure lesions of mitochondria, \"Z\" line and miofibrils.
46

NMR studies on 2-oxoglutarate oxygenases

Leung, Ivanhoe K. H. January 2012 (has links)
No description available.
47

Aplikace L-carnitinu do peritoneální dutiny potkana

Drozd, Eliška January 2019 (has links)
This thesis (Application of L-carnitine to the peritoneal cavity of rat) deals with the effect of L-carnitine on the inflammatory response of the organism. L-carnitine is a common part of the body's physiological functions. It is part of the lipid metabolism in the mammalian organism. Its effect helps to transfer fatty acids from the cytosol to the mitochondria. The literary part deals with the current state of L-carnitine research and its effects in the body. It also deals with methods of applying active substances to or-ganisms and blood elements, namely leukocytes and their functions associated with inflammatory reaction. The experimental section deals with the influence of L-carnitine on the course of inflammatory reaction in the peritoneal cavity. It also deals with the determination of the dynamics of the inflammatory response, which is evalu-ated using absolute and differential leukocyte counts at two time points.
48

Physiological and production responses of intensively managed Ostriches to L-Carnitine

Hajibabaei, Ali 10 January 2014 (has links)
This set of experiments evaluated the physiological responses of intensively managed ostriches to L-carnitine. In experiment 1, 32 female and 16 male Zimbabwean Blue Neck and South African Black Neck breeders (n=48 of each sub-species; eight years old), were investigated in 16 breeder units of two females and one male (Trio), in a completely randomised design within four treatments and four replicates over an 8-month period during the breeding season. The same basal diet was fed supplemented with 0 (T0, control), 125 (T125), 250 (T250) or 600 (T600) mg/kg L-carnitine. T600 improved the egg production percentage, egg fertility percentage and the hatchability of set eggs for Black-Necks and Blue-Necks, respectively, and the hatchability of fertile eggs in Black Necks. L-carnitine did not affect egg shape index, defective eggs, egg weight, embryonic and post-hatch mortality. In experiment 2, 12 Black Neck males (5.5 years old) were allocated to three treatments (T0, T250 and T500) and four replicates. Semen samples were collected once a month over three months. L-carnitine had a significant effect on semen volume, sperm motility, live sperm percentage and sperm count, but had no significant effect on abnormal sperm percentage. In experiment 3, 32 day-old Black Neck ostrich chicks were allocated to treatments T0, T125, T250 and T600 with four replicates of two chicks. Chicks were vaccinated against inactive Newcastle Disease (ND) vaccine at day 30 as primary, and at day 51 as booster immunisation. ND antibody responses in the sera were monitored over three phases at 51, 70 and 80 days. Anti-NDV antibodies were detected using a modified chicken anti-NDV enzyme-like immunosorbent assay (ELISA). The treatments and the time periods and their interactions influenced ND antibody responses. T125 and T250 had the highest level of ND antibody response compare to the other groups. There were no differences in ND antibody response between T0 and T600 as well as T125 and T250. The highest ND antibody responses were recorded at day 70. Experiment 4 was designed the same as 3, to determine chicks’ growth responses over the 60-day period. Live weight and live weight gain values of T125 and T250 did not differ from those of T0. T600 had the lowest feed conversion ratio (FCR) during the total period. Feed intake (FI) was reduced in the T125 and T600 treatments compared to T0 and T250 over the total period. T125 gave the lowest FI and FCR responses over the total period, whereas there was no difference between T0 and T250. These results suggest that dietary T600 can have a beneficial effect on egg production, fertility and hatchability in the Black and Blue Neck breeders and T250 might improve sperm quality in males. In ostrich chicks T125 and T250 had positive effects on immune responses and T125 can improve the performance by decreasing the FCR. In contrast, the suppressive effect of a high inclusion level (T600) might indicate that ostrich chicks are sensitive to high inclusion levels that could cause adverse effects. / gm2013 / Animal and Wildlife Sciences / Thesis (PhD)--University of Pretoria, 2013. / Unrestricted
49

Enhancing Boar Reproductive Performance for Purposes of Artificial Insemination

Kozink, Daniel Michael 16 December 2002 (has links)
The objectives were to: 1) determine if im treatments of Lutalyse expedited the training of sexually inexperienced boars for semen collection and increased spermatozoal output, and 2) determine the effects of dietary L-carnitine supplementation on boar libido, semen quality, sperm production, and maintenance of sperm motility during liquid storage. Experiment 1 utilized lean-type, terminal-line boars (National Pig Development, Roanoke Rapids, NC) (n = 40; 177.4 ± 2.4 d of age and 112.8 ± 2.0 kg body weight) that had not previously experienced natural mating. Boars were individually moved twice weekly for 6 weeks (total of 12 training sessions) to a semen collection room equipped with an artificial sow. Upon entering the semen collection room, boars received in treatments of either deionized water (4 mL, n = 10) or Lutalyse at doses of 5 mg (n = 10), 10 mg (n = 10), or 20 mg (n = 10), and subsequently received a libido score of 1 to 5 (1 = no interest in the artificial sow; 5 = mounting the artificial sow and allowing semen collection). The percentages of boars successfully trained for semen collection during the experimental period were similar (P > 0.05) for controls (20%) and boars receiving 5 mg (30%), 10 mg (20%), or 20 mg (10%) of Lutalyse. Average libido score for boars receiving 10 mg Lutalyse (2.35 ± 0.08) was greater (P < 0.05) than for controls (2.14 ± 0.06). Libido score for the 20 mg treatment group were (1.78 ± 0.06) lower (P < 0.05) compared to the other treatment groups. Characteristics of ejaculates (volume, gel weight, sperm concentration, total spermatozoa) from control boars and boars treated with Lutalyse at doses of 5, 10, or 20 mg were similar (P > 0.05). For Exp. 2, the same group of boars was utilized in two similar trials (Trial 1, 1a, 1b: n = 9 for control and L-carnitine-treated boars; Trial 2, 2a, 2b: n = 10 for control and L-carnitine-treated boars). Boars were fed a fortified, corn and soybean meal-based diet at a rate of 2 kg/d. Boars that were randomly selected for L-carnitine treatment received the same diet mixed with L-carnitine to achieve supplementation of 500 mg/d. For 16 wk, semen was collected weekly via the gloved hand method and was analyzed for gel-free volume, gel weight, sperm concentration, sperm per ejaculate, and characteristics of sperm motility. Time to ejaculation (reaction time), duration of ejaculation, and number of false mounts were also recorded for each collection. Trials 1a and 2a were conducted during weeks 16 and 17 for each respective trial. Boars were collected once on 4 consecutive days, allowed 4 d of rest, and then collected again, to estimate daily spermatozoal production. At the end of 16 wk, a semen sample was also processed and extended in Beltsville Thawing Solution (BTS) to achieve a dilution of 3 x 109 spermatozoa/100 mL-dose for Trials 1b and 2b. The extended semen was stored in plastic bottles at 18°C and motility was evaluated daily for 7 d post collection. L-carnitine supplementation for 16 wk had no effects on semen volume, gel weight, total number of sperm cells per ejaculate, reaction time, or sperm motility (P > 0.1). Boars receiving the L-carnitine-supplemented diet displayed an increase in the number of false mounts before ejaculating and an increase in sperm concentration (P < 0.05) in Trial 2. A treatment by week interaction was detected for sperm concentration in Trial 2 (P < 0.005). Increased sperm concentrations in L-carnitine-treated boars were demonstrated after only one week of feeding the respective diets. Given that the production of a mature sperm cell requires 7 to 8 wk in boars, it is therefore difficult to conclude that differences in sperm concentration were due solely to treatment. Daily spermatozoal production was similar between control boars and boars supplemented with L-carnitine (P > 0.1) for both Trials 1a and 2a. L-carnitine supplementation did not affect percent motility in Trials 1b and 2b or sperm progressive motility in Trial 2b during 7 d storage (P > 0.1). A treatment by day interaction was determined for sperm velocity (P < 0.05) in Trial 2b. L-carnitine supplementation decreased mean sperm velocity significantly after 2 d of storage. Overall, L-carnitine had no beneficial effects on boar libido, semen quality, sperm production, or maintenance of sperm motility during liquid storage. However, Lutalyse increased libido scores, but did not affect the number of boars trained for semen collection or number of spermatozoa ejaculated. / Master of Science
50

Conséquences d’une restriction de croissance intra-utérine et du sexe biologique sur le métabolisme des acides gras dans les cardiomyocytes de rats foetaux

Gravel, Cynthia 05 1900 (has links)
Il est désormais accepté qu'un environnement foetal défavorable prédispose à des maladies chroniques qui surviennent à l'âge adulte. Il a été démontré dans notre laboratoire qu'une diminution de perfusion placentaire induit une redistribution du débit sanguin vers le coeur chez le foetus ainsi qu’une restriction de croissance intrautérine. De plus, un remodelage et une diminution de la contractilité des cardiomyocytes ont été observés chez les femelles devenues adultes. En période périnatale, l’utilisation des acides gras comme substrat énergétique devient plus importante que celle du glucose au niveau des cardiomyocytes. Considérant qu'un mécanisme s'est mis en place in utero, nous émettons l’hypothèse que le transfert de la voie de l’utilisation du glucose vers l’utilisation des acides gras se fait plus tôt chez les foetus en restriction de croissance. L’objectif de cette étude est de mesurer, dans les coeurs foetaux, les constituants du métabolisme des acides gras, soit le transporteur principal des acides gras, la carnitine palmitoyltransférase‒1‒alpha, ainsi que ses protéines associées soit l’acyl‒CoenzymeA synthétase‒1 et le canal anionique voltage‒dépendant de type 1. Nous mesurerons l’activité du cytochrome c oxydase et le nombre de mitochondries. L’influence du sexe et la condition foetale (restriction de croissance intrautérine vs contrôle) seront comparés. Nous avons observé que l’expression protéique de la carnitine palmitoytransférase‒1α et de l’acyl‒CoenzymeA synthétase‒1 est significativement augmentée, mais pas celle du canal anionique voltage‒dépendant de type 1, dans les coeurs de foetus en restriction de croissance intrautérine femelles. Le nombre et l’activité des mitochondries est semblable dans tous les groupes. Ces résultats suggèrent que la condition foetale et le sexe altèrent la quantité du transporteur des acides gras, la carnitine palmitoytransférase‒1α, au niveau traductionnel sans toutefois affecter l’activité du cytochrome c oxydase et le nombre de mitochondries. À long terme, nos études permettront de mieux comprendre les conséquences et causes de la RCIU afin d’en permettre la prévention. / It is widely accepted that an adverse fetal environment predisposes to chronic diseases that occur in adulthood. In our laboratory, it has been shown that a decrease in placental perfusion induced blood flow redistribution to the heart in fetus as well as an intrauterine growth restriction. Furthermore, remodeling and decreased contractility of cardiomyocytes were observed in adult offspring females. In perinatal period, the use of fatty acids as an energy substrate becomes more important than glucose in cardiomyocytes. Whereas a mechanism is in place in utero, we proposed the hypothesis that the transfer from the use of glucose as fuel towards fatty acids occurs earlier in intrauterine growth restriction fetuses. The objective of this study is to measure, in fetal hearts, the components of fatty acid metabolism, the main carrier of fatty acids, carnitine palmitoyltransférase‒1α, and its associated proteins namely acyl‒coenzymeA synthase‒1 and voltage‒dependant anion channel 1. We will measure the cytochrome c oxidase activity and the number of mitochondria. Influence of sex and fetal condition (intrauterine growth restriction vs control) will be compared. We observed that protein expression of carnitine palmitoyltranferase-1α and acyl-coenzyme A synthetase long-chain 1 is significantly increased, but not that of the voltage-dependant anion channel 1, in hearts of female fetus IUGR. The number and the activity of mitochondria are similar in all the groups. These results suggest that fetal condition and sex alter the quantity of the acid transporter carnitine palmitoyltranferase-1α has at the translation level without affecting the activity of the cytochrome c oxidase and the number of mitochondria.

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