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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

Diffuse Large B-Cell Lymphoma: A Metabolic Disorder?

Tanios, Georges, Aranguren, Ines M., Goldstein, Jack S., Patel, Chirag B. 02 December 2013 (has links)
Objective: Challenging differential diagnosis Background: B cell lymphoma constitutes 80-85% of cases of Non Hodgkin's lymphoma in the Untied States. Metabolic complications may arise from the disease itself or through its end organ involvement. Case Report: We describe a case of a diffuse large B cell lymphoma diagnosed by abdominal computed tomography after it initially presented as hypoglycemia not correctable by dextrose infusion that instead resulted in increased anion gap metabolic acidosis with elevated lactate levels. Conclusions: The case illustrates how lymphomas can present unusually with hypoglycemia and lactic acidosis, the latter being an ominous sign that can occur without liver involvement. In this regard, the case demonstrates the metabolic sequelae of lymphoma that should raise suspicion for an underlying process. This has implications for diagnosis, treatment, and patient survival. Attention should be paid especially in the primary care setting in order to minimize delays in diagnosis.
12

Diffuse Large B-Cell Lymphoma: A Metabolic Disorder?

Tanios, Georges, Aranguren, Ines M., Goldstein, Jack S., Patel, Chirag B. 02 December 2013 (has links)
Objective: Challenging differential diagnosis Background: B cell lymphoma constitutes 80-85% of cases of Non Hodgkin's lymphoma in the Untied States. Metabolic complications may arise from the disease itself or through its end organ involvement. Case Report: We describe a case of a diffuse large B cell lymphoma diagnosed by abdominal computed tomography after it initially presented as hypoglycemia not correctable by dextrose infusion that instead resulted in increased anion gap metabolic acidosis with elevated lactate levels. Conclusions: The case illustrates how lymphomas can present unusually with hypoglycemia and lactic acidosis, the latter being an ominous sign that can occur without liver involvement. In this regard, the case demonstrates the metabolic sequelae of lymphoma that should raise suspicion for an underlying process. This has implications for diagnosis, treatment, and patient survival. Attention should be paid especially in the primary care setting in order to minimize delays in diagnosis.
13

Tratamento adicional da acidose láctica ruminal aguda em bovinos por meio de infusão de solução salina hipertônica (7,2%) / Additional treatment of acute lactic ruminal acidosis in cattle by infusion of hypertonic saline solution (7.2%)

Rodrigues, Frederico Augusto Mazzocca Lopes 11 September 2009 (has links)
A solução salina hipertônica (SSH) é reconhecida por seu efeito ressuscitador em animais com choque hipovolêmico, aumentando a passagem de fluidos de outros órgão e tecidos para a corrente circulatória. Bovinos acometidos com acidose láctica ruminal aguda (ALRA) freqüentemente apresentam quadros de variável desidratação devido à passagem de fluidos do organismo para o rúmen, além do estabelecimento de acidose sistêmica, devido à absorção de ácido láctico ruminal. Como o SSH aumenta o volume de urina excretada seria plausível o efeito desta solução na excreção de íons H+ e lactato na urina de animais com ALRA. Doze bovinos machos, mestiços e de um ano de idade foram utilizados para avaliar o efeito do tratamento adicional de SSH sobre a (ALRA). Após período de adaptação e implantação de cânula no rúmen os animais foram submetidos à indução de ALRA por meio de quantidade calculada de sacarose administrada diretamente no rúmen. Após 20 horas da indução os animais foram aleatoriamente divididos em dois grupos iguais. Um deles (SSH) foi tratado com 5 mL/kg P.V. de uma solução de SSH a 7,5 %, dentro de 15 min, e 20 mL/kg/P.V. de solução salina isotônica (SSI) no decorrer dos próximos 165 minutos. Foram ainda retirados 5 L de conteúdo ruminal e adicionado igual quantidade de água no rúmen. O outro grupo (SSI) foi medicado da mesma forma, com exceção do SSH que foi substituído por 5 mL/kg PV de SSI. Variáveis foram mensuradas no momento 0 (MO), na 20 h (M20h) e no decorrer dos tratamentos com ISS ou SSH (M30´, M60´, M120´e M180´). Ao término desses tratamentos todos os animais foram medicados com quantidades calculadas de solução de 1,3 % de bicarbonato de sódio IV. A acidose ruminal obtida pela indução foi de grau médio a moderado, a acidose sistêmica e a intensidade de desidratação de graus moderados. A adição de água no rúmen nos primeiros 30 min. uma ligeira acidemia (0,03 graus de pH) acompanhada de discreta hipercapnia, além de gerar um aumento significativo na osmolalidade sérica favorecendo a absorção de fluidos do rúmen para a corrente sanguínea, avaliada pelo aumento de osmolalidade ruminal. Essa condição melhorou temporariamente o restabelecimento do volume globular. O tratamento com SSH ainda permitiu a maior excreção urinária, acompanhada de aumento da taxa de filtração glomerular e maiores eliminações de íons H+, lactato e fósforo. Existiu uma alta relação positiva entre a excreção de fósforo e pH urinários (R2= 0,562). O tratamento com SSH não gerou quaisquer reações colaterais. Os presentes resultados indicam que é vantajoso e adequado o tratamento de quadros de ALRA com SSH, em relação ao protocolo com SSI. / Hypertonic saline solution (HSS) is known by causing a resurrection effect in animals with hypovolemic shock, through the passage of fluids from other organs and tissues to the blood stream. Cattle with acute rumen lactic acidosis (ARLA) usually present different degrees of dehydration, caused by the migration of fluids from the body toward the rumen, besides the development of systemic acidosis by the absorption of ruminal lactic acid. As the HSS increases the volume of excreted urine would be plausible to suggest that this solution could enhance the urinary excretion of H+ and lactate in cattle with ARLA. Twelve yearling, cross-bred, male cattle were used to evaluate the effect of the additional treatment with HSS on cattle with ARLA. After an adaption period, when a rumen cannula was implanted, the animals were submitted to an induction of ARLA by a calculated amount of sucrose into the rumen. Twenty hours later the cattle were randomly divided in two equal groups. The 1st group was treated with 5 mL/kg BW with 7.5 % HSS, within 15 min, and 20 mL/ kg BW of isotonic saline solution (ISS) for the next 165 min. Five litres of rumen fluid was withdraw and equal volume of water was added into the rumen. The following group was treated equally, but the HSS that was changed to the same volume of ISS. Several variables were measured at different times of the experiment. At the end of this protocol all animals were treated with calculated amounts of 1.3% sodium bicarbonate solution IV. The induction caused a medium to moderate ruminal acidosis, and a moderate degree of systemic acidosis and dehydration. The administration of water caused a sharp decrease in the rumen osmolality. The treatment with HSS caused a mild academia (0.03 degree of pH) followed by a discrete hypercapnia, besides generating a significant increase in the serum osmolality, which favours the rumen fluid absorption into the blood stream. This condition improved temporarily the recovering of globular volume. The treatment with HSS also increased the urinary volume excreted followed by the improvement of the glomerular filtration ratio and the global excretion of H+, lactate and phosphorus. A high positive relationship was found between the excretion of urinary phosphorus and urine pH (R2 = 0,562). No side effects were seen in cattle treated with HSS. The present results show that is beneficial and adequate the treatment of ARLA with HSS, as compared to the protocol with ISS.
14

Tratamento adicional da acidose láctica ruminal aguda em bovinos por meio de infusão de solução salina hipertônica (7,2%) / Additional treatment of acute lactic ruminal acidosis in cattle by infusion of hypertonic saline solution (7.2%)

Frederico Augusto Mazzocca Lopes Rodrigues 11 September 2009 (has links)
A solução salina hipertônica (SSH) é reconhecida por seu efeito ressuscitador em animais com choque hipovolêmico, aumentando a passagem de fluidos de outros órgão e tecidos para a corrente circulatória. Bovinos acometidos com acidose láctica ruminal aguda (ALRA) freqüentemente apresentam quadros de variável desidratação devido à passagem de fluidos do organismo para o rúmen, além do estabelecimento de acidose sistêmica, devido à absorção de ácido láctico ruminal. Como o SSH aumenta o volume de urina excretada seria plausível o efeito desta solução na excreção de íons H+ e lactato na urina de animais com ALRA. Doze bovinos machos, mestiços e de um ano de idade foram utilizados para avaliar o efeito do tratamento adicional de SSH sobre a (ALRA). Após período de adaptação e implantação de cânula no rúmen os animais foram submetidos à indução de ALRA por meio de quantidade calculada de sacarose administrada diretamente no rúmen. Após 20 horas da indução os animais foram aleatoriamente divididos em dois grupos iguais. Um deles (SSH) foi tratado com 5 mL/kg P.V. de uma solução de SSH a 7,5 %, dentro de 15 min, e 20 mL/kg/P.V. de solução salina isotônica (SSI) no decorrer dos próximos 165 minutos. Foram ainda retirados 5 L de conteúdo ruminal e adicionado igual quantidade de água no rúmen. O outro grupo (SSI) foi medicado da mesma forma, com exceção do SSH que foi substituído por 5 mL/kg PV de SSI. Variáveis foram mensuradas no momento 0 (MO), na 20 h (M20h) e no decorrer dos tratamentos com ISS ou SSH (M30´, M60´, M120´e M180´). Ao término desses tratamentos todos os animais foram medicados com quantidades calculadas de solução de 1,3 % de bicarbonato de sódio IV. A acidose ruminal obtida pela indução foi de grau médio a moderado, a acidose sistêmica e a intensidade de desidratação de graus moderados. A adição de água no rúmen nos primeiros 30 min. uma ligeira acidemia (0,03 graus de pH) acompanhada de discreta hipercapnia, além de gerar um aumento significativo na osmolalidade sérica favorecendo a absorção de fluidos do rúmen para a corrente sanguínea, avaliada pelo aumento de osmolalidade ruminal. Essa condição melhorou temporariamente o restabelecimento do volume globular. O tratamento com SSH ainda permitiu a maior excreção urinária, acompanhada de aumento da taxa de filtração glomerular e maiores eliminações de íons H+, lactato e fósforo. Existiu uma alta relação positiva entre a excreção de fósforo e pH urinários (R2= 0,562). O tratamento com SSH não gerou quaisquer reações colaterais. Os presentes resultados indicam que é vantajoso e adequado o tratamento de quadros de ALRA com SSH, em relação ao protocolo com SSI. / Hypertonic saline solution (HSS) is known by causing a resurrection effect in animals with hypovolemic shock, through the passage of fluids from other organs and tissues to the blood stream. Cattle with acute rumen lactic acidosis (ARLA) usually present different degrees of dehydration, caused by the migration of fluids from the body toward the rumen, besides the development of systemic acidosis by the absorption of ruminal lactic acid. As the HSS increases the volume of excreted urine would be plausible to suggest that this solution could enhance the urinary excretion of H+ and lactate in cattle with ARLA. Twelve yearling, cross-bred, male cattle were used to evaluate the effect of the additional treatment with HSS on cattle with ARLA. After an adaption period, when a rumen cannula was implanted, the animals were submitted to an induction of ARLA by a calculated amount of sucrose into the rumen. Twenty hours later the cattle were randomly divided in two equal groups. The 1st group was treated with 5 mL/kg BW with 7.5 % HSS, within 15 min, and 20 mL/ kg BW of isotonic saline solution (ISS) for the next 165 min. Five litres of rumen fluid was withdraw and equal volume of water was added into the rumen. The following group was treated equally, but the HSS that was changed to the same volume of ISS. Several variables were measured at different times of the experiment. At the end of this protocol all animals were treated with calculated amounts of 1.3% sodium bicarbonate solution IV. The induction caused a medium to moderate ruminal acidosis, and a moderate degree of systemic acidosis and dehydration. The administration of water caused a sharp decrease in the rumen osmolality. The treatment with HSS caused a mild academia (0.03 degree of pH) followed by a discrete hypercapnia, besides generating a significant increase in the serum osmolality, which favours the rumen fluid absorption into the blood stream. This condition improved temporarily the recovering of globular volume. The treatment with HSS also increased the urinary volume excreted followed by the improvement of the glomerular filtration ratio and the global excretion of H+, lactate and phosphorus. A high positive relationship was found between the excretion of urinary phosphorus and urine pH (R2 = 0,562). No side effects were seen in cattle treated with HSS. The present results show that is beneficial and adequate the treatment of ARLA with HSS, as compared to the protocol with ISS.
15

Review of mitochondrial DNA and mitochondrial-associated disorders

Olukorede, Opeoluwa 03 November 2023 (has links)
Mitochondrial diseases are caused by gene mutations in either mitochondrial DNA (mtDNA) or nuclear DNA (nDNA) and they are among one of the most common forms of inherited disorders. It is estimated that 1 out of every 5000 individuals will develop a mitochondrial disease in their lifetime. Due to the crucial and widespread functionality of mitochondria in human cells, prolonged diseases of the mitochondria affect cells of the brain, heart, liver, muscles and kidneys and can lead to multi-organ failure in some patients. Inherited or acquired mitochondrial diseases can present at any stage of life, affecting both children and adults. Since its discovery, the mitochondrial genome has been analyzed and sequenced with increasing ease and this process has helped recognize various mitochondrial disorders as the root of genetic diseases. This paper will explore the unique properties of the mitochondrion and its genome, examine the relationship between mtDNA and some common myopathies such as Leigh syndrome (LS) or maternally inherited Leigh syndrome (MILS), mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) in order to explore commonalities and differences in their inheritance patterns and their effect on mitochondrial function. Although studies have shown that these conditions generally affect the process of oxidative phosphorylation in mitochondria, because of the wide variety of presentations of this disease, further research is needed to understand the different etiologies, as well as to explore novel therapies to treat them.
16

Dysfonctions mitochondriales associées à l’acidose lactique du Saguenay-Lac-Saint-Jean révélées par l’étude d’un nouveau modèle murin de la maladie

Cuillerier, Alexanne 01 1900 (has links)
No description available.
17

Impact de la mutation du gène LRPPRC sur la vulnérabilité induite par un stress inflammatoire et nutritionnel in vitro et sur la morphologie cérébrale ex vivo

de Melo Almeida, Rafaela 08 1900 (has links)
No description available.
18

L'application de la métabolomique à la découverte de nouveaux biomarqueurs chez les patients atteints d'acidose lactique

Thompson Legault, Julie 04 1900 (has links)
L’acidose lactique du Saguenay-Lac-St-Jean, ou syndrome de Leigh de forme canadienne-française (LSFC), est une maladie mitochondriale neurodégénérative causée par des mutations du gène LRPPRC et caractérisée par des crises d’acidose menant au décès en bas âge. On ne comprend pas encore les causes exactes de ces crises, et aucun traitement n’est actuellement disponible. L’objectif de cette étude a été de comparer le profil des métabolites sanguins et urinaires chez des sujets LSFC et des témoins, avant et après un repas, par une approche métabolomique ciblée. Le projet s’inscrit dans une démarche à long terme visant l’identification de biomarqueurs prédictifs des crises, permettant d'intervenir plus rapidement afin d’éviter le décès. Les échantillons biologiques ont été prélevés chez 9 sujets atteints du LSFC et 9 témoins appariés, à jeun et 90 minutes après un repas standardisé. Les analyses incluent un bilan biochimique et hormonal, un profil des acides aminés, des acides gras, des acides organiques et des acylcarnitines. Les métabolites significativement modifiés chez les patients peuvent être classés en deux catégories : (i) le reflet d’une dysfonction mitochondriale, et plus particulièrement de l’accumulation d’équivalents réduits en amont de la chaîne respiratoire, et (ii) des indices de risque cardiométabolique, qui s’observent davantage chez les patients adultes malgré leur jeune âge. Ainsi, il serait intéressant d’inclure au traitement des stratégies visant la diminution des facteurs de risque cardiométabolique, notamment par une modification des habitudes de vie. Notre étude démontre la pertinence d’avoir recours à la métabolomique dans l’étude des désordres de la phosphorylation oxydative. / L’acidose lactique du Saguenay-Lac-St-Jean, ou syndrome de Leigh de forme canadienne-française (LSFC), est une maladie mitochondriale neurodégénérative causée par des mutations du gène LRPPRC et caractérisée par des crises d’acidose menant au décès en bas âge. On ne comprend pas encore les causes exactes de ces crises, et aucun traitement n’est actuellement disponible. L’objectif de cette étude a été de comparer le profil des métabolites sanguins et urinaires chez des sujets LSFC et des témoins, avant et après un repas, par une approche métabolomique ciblée. Le projet s’inscrit dans une démarche à long terme visant l’identification de biomarqueurs prédictifs des crises, permettant d'intervenir plus rapidement afin d’éviter le décès. Les échantillons biologiques ont été prélevés chez 9 sujets atteints du LSFC et 9 témoins appariés, à jeun et 90 minutes après un repas standardisé. Les analyses incluent un bilan biochimique et hormonal, un profil des acides aminés, des acides gras, des acides organiques et des acylcarnitines. Les métabolites significativement modifiés chez les patients peuvent être classés en deux catégories : (i) le reflet d’une dysfonction mitochondriale, et plus particulièrement de l’accumulation d’équivalents réduits en amont de la chaîne respiratoire, et (ii) des indices de risque cardiométabolique, qui s’observent davantage chez les patients adultes malgré leur jeune âge. Ainsi, il serait intéressant d’inclure au traitement des stratégies visant la diminution des facteurs de risque cardiométabolique, notamment par une modification des habitudes de vie. Notre étude démontre la pertinence d’avoir recours à la métabolomique dans l’étude des désordres de la phosphorylation oxydative.
19

Antimicrobial plants of Australia have the potential to prevent lactic acidosis in ruminants

Hutton, Peter January 2008 (has links)
[Truncated abstract] Antimicrobial growth promoters are added to feed to prevent lactic acidosis in ruminant animals by selectively inhibiting rumen bacteria that produce lactic acid. However, recently imposed or impending bans on the use of antimicrobial growth promoters in animal production have lead to a critical need to find practical alternatives that are safe for the animal and consumer and that obtain similar production benefits. I investigated bioactive plants of Australia for their potential to prevent lactic acidosis in ruminants. The unifying hypothesis tested was that plants would be identified that selectively inhibit lactic acid-producing bacteria and consequently protect against lactic acidosis. This hypothesis was tested in a three phase process: phase 1, plant selection and collection; phase 2, a three stage protocol for screening plants and essential oils; phase 3, in vivo experiments and chemical fractionation of the most promising plant. I developed an in vitro bioassay that simulated acidosis by adding glucose to rumen fluid in Bellco tubes and incubating for 5 h (Chapter 4). The pH and gas production were used as indicators of acidosis and fermentation activity. I used this bioassay to screen ninety-five plants (dried and ground material from 79 species) and ten essential oils and included a negative control (oaten chaff) and a positive control (virginiamycin). One plant, Eremophila glabra, produced a similar pH (5.63) to the positive control (5.43) although it inhibited gas production to a moderate extent (P < 0.05). ... Seven serrulatane diterpenes were identified to be the major secondary metabolites in E. glabra. The metabolites were screened using a broth dilution and microtitre spectrophotometry method and were selective against S. bovis at between 320 and 1077 [mu]g/ mL. The serrulatanes from E. glabra were probably responsible for the activity against acidosis that I observed in vitro, because they selectively inhibited lactateproducing bacteria. It is also possible that a synergy between serrulatanes and possibly other metabolites are responsible for the activity observed in vitro. The results from my experiments support the role that bioactive plants may have to replace the antibiotics that are added to livestock feed. Australian plants were identified containing compounds that were active against the bacterial processes responsible for ruminant acidosis. To my knowledge this is the first work undertaken to identify bioactive plants of Australia for their potential to prevent acidosis. I developed in vitro screening bioassays that targeted key indicators of acidosis. These bioassays enabled me to identify 5 plants from the 104 screened that could potentially control acidosis. One of these plants in particular, E. glabra, showed a level of activity in vitro that was comparable to antibiotic protection against acidosis. The exciting in vitro results were not demonstrated in vivo but only one dose level of E. glabra was used, which was based on the in vitro work. In contrast to the in vitro system the rumen is a continuous flow system with greater complexity and it is possible that the concentration of E. glabra that I used in vivo was not optimum. This places importance on future dose response experiments to confirm the efficacy of E. glabra in vivo.
20

Impact de facteurs sanguins et d'agents thérapeutiques sur la survie de fibroblastes de sujets atteints de la forme canadienne-française du syndrome de Leigh (LSFC)

Rivard, Marie-Eve 08 1900 (has links)
La forme canadienne-française du syndrome de Leigh (LSFC) est une maladie métabolique associée à une déficience en cytochrome oxydase (COX) et caractérisée par des crises d’acidose lactique, menant à une mort prématurée. Les mécanismes qui sous-tendent l’induction des crises restent inconnus et il n’existe aucune thérapie efficace pour les prévenir. Cette étude vise à caractériser l'effet de facteurs métaboliques périphériques potentiellement altérés chez les patients LSFC sur la mort de lignées cellulaires issues de ces patients et de témoins puis, à identifier des agents thérapeutiques pouvant la prévenir. Nous postulons que (i) ces facteurs métaboliques induiront une mort prématurée des cellules de patients et que (ii) les interventions susceptibles de la prévenir pallieront les conséquences de la déficience en COX, soit la diminution des taux d’adénosine triphosphate (ATP) et l’augmentation du stress oxydant, du nicotinamide adénine dinucléotide (NADH) et des lipides toxiques. Un criblage de 8 facteurs sanguins et 10 agents thérapeutiques a été réalisé. Les paramètres mesurés incluent la nécrose, l’apoptose, l’ATP et l’activité de la COX. Les fibroblastes LSFC sont plus susceptibles à la mort par nécrose (39±6%) induite par du palmitate plus lactate, un effet associé à des niveaux d’ATP diminués (53±8%). La mort cellulaire est réduite de moitié par l’ajout combiné d’agents ciblant le NADH, l’ATP et les lipides toxiques, alors que l’ajout d’antioxydants l’augmente. Ainsi, un excès de nutriments pourrait induire la mort prématurée des cellules LSFC et, pour atténuer cette mort, il serait important de combiner plusieurs interventions ciblant différents mécanismes. / Leigh syndrome French-Canadian variant (LSFC) is a metabolic disease associated with cytochrome c oxidase (COX) deficiency and characterized by episodes of lactic acidosis, referred to as “crisis”, leading to death at an early age. The mechanisms underlying a crisis and its cellular consequences remain elusive, and there is no effective therapy. The aim of this study was to characterize the effect of peripheral metabolic factors that are potentially altered in patients with LSFC on their cells death and to identify therapeutic agents able to prevent them using cell-lineage from LSFC patients and controls. The hypothesis are that (i) these metabolic factors can induce premature death in patient cells, and (ii) interventions that could rescue these cells may target potential consequences of COX deficiency, namely low adenosine triphosphate (ATP), high nicotinamide adenine dinucleotide (NADH) and toxic lipids, as well as oxidative stress. A screening of 8 blood factors and 10 therapeutic agents was conducted in fibroblasts. Parameter measured included cell death by necrosis and apoptosis, as well as ATP level and COX activity. LSFC fibroblasts were more susceptible to necrosis (39±6%) induced by high palmitate plus lactate and this was associated with a lower ATP (53±8%). Cell death decreased 2-fold with combined interventions, which presumably act on NADH, ATP, and the accumulation of toxic lipids, but increased with antioxidants. Collectively, our results emphasize the importance of nutrient overload as a factor eliciting premature cell death in LSFC cells and of combining interventions acting through various mechanisms for cell death rescue.

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