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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.
291

ROLE AND MODULATION OF OXIDATIVE STRESS IN AGE-ASSOCIATED CHRONIC RENAL PATHOLOGIES

Christine Percy Unknown Date (has links)
Age-dependent changes in the kidney are often debilitating, can be life-threatening and are a significant cause of increasing health costs worldwide. Excessive fibrosis, a general lack of regenerative ability and an increase in apoptosis in cells that determine healthy renal function work together to cause chronic kidney disease (CKD). This thesis reviewed the literature and then tested hypotheses developed from this review, to provide information on the molecules and mechanisms that determine the age-dependent changes of CKD. Results in this thesis provide a comprehensive analysis of the molecular, structural and functional changes of age-related CKD, with particular attention paid to the longevity gene p66Shc. The present studies were able to make use of established ageing rodent colonies of various phenotypes. In the first of the research Chapters, rat models of age-related CKD linked with obesity and hypertension were used. The research tested the hypothesis that each cause of age-related renal change (ageing, obesity or hypertension) would have differing underlying genetic modifications that could explain any differences in renal structure and function. In particular, alterations in oxidant handling and energy metabolism were investigated to identify markers for age-related CKD. Young (3 months) and old (20-24 months) spontaneously-hypertensive rats (SHR), normotensive Wistar- Kyoto (WKY) and Wistar rats (normotensive, with excess visceral and peri-renal fat in ageing) (N = 4 per group) were compared for renal functional and physiological parameters, fibrosis, inflammation and oxidative stress. All of the analyses indicated the old obese Wistars had the greatest renal injury, inflammation and markers of oxidative stress. In particular, % phosphop66/ p66Shc, considered an oxidant stress marker, was significantly increased in these animals (p<0.05). These results suggest that obesity and hypertension have differing oxidant handling and signalling pathways that act in the pathogenesis of age-related CKD, and that obesity alone may be a key causative mechanism of age-related CKD. x Oxidative stress is thought to be a major cause of age-related CKD. In chapter 5, the following hypotheses were tested: (1) that the added stress of ischemia-reperfusion (IR) injury on the ageing kidney would create an environment for increased injury; and (2) that this injury could be modulated by using a short-term anti-ageing strategies. Old (20-24 month) and young (3 month) WKY rats (females, N = 4 per group) were used to compare the effects of bilateral, 45-minute, IR injury with and without calorie restriction (a 40% reduction in food from baseline) or vitamin E (daily gavage of 1000IU) for 10 days prior to IR surgery and then for the length of recovery from IR (4 days). Histological, functional and molecular analyses were used. Old rats had significantly worsened renal injury compared with young rats with IR. Proteins involved in oxidative stress (HO-1, p66Shc and phospho-p66Shc), survival (PKB and phospho-PKB), apoptosis (Bax, Bcl-2), inflammation and fibrosis (NF-κB, tumour necrosis factor-α/TNFα, transforming growth factor-β/TGFβ) were differentially expressed according to age and development of IR injury. Vitamin E-supplemented animals showed minimal improvement and calorie restriction generally worsened the outcome in both young and old animals. Changes in protein expression support the notion that these short-term calorie-restricted animals were in a catabolic state, perhaps similar to protein energy wasting seen in some of the human dialysis population. In chapter 6 in vitro experimental models using primary human renal proximal tubular epithelial cells (PTECs) were utilised. Successive passaging in culture of the PTECs showed increasing markers of senescence and oxidative stress. The degree of senescence correlated with expression of the oxidative stress marker phospho-p66Shc and alterations in other key signalling molecules. Hydrogen peroxide (5mM for 1 hour) was used to simulate a burst of oxidative stress and the effects of leptin and resveratrol was examined. Histological and molecular analyses demonstrated some links with the previous in vivo results, for example the involvement of phospho-p66Shc in the development of cell senescence but generally the in vitro experiments did not replicate in vivo xi findings. The lack of complex, heterogeneous, cellular and growth factor/cytokine interactions of the in vivo environment are thought to be a factor in this disappointing result. The tendency for development of CKD differs in males and females in ageing humans. In chapter 7 characteristics of age-related CKD in old male and female rats were compared, summarising data on the WKY rats from Chapters 3 to 5. Minor differences between males and females in histology, function and protein expression are described, but these do not adequately reflect the findings of gender dimorphisms in development of CKD, reported from human and experimental in vivo studies. These experiments demonstrate some of the pathogenetic mechanisms of age-related CKD. The results indicate pathways or molecules that may be targeted in future therapies or may be used as biomarkers of early development of age-related CKD. In particular, the modification of p66Shc may one day be used to minimize renal damage and promote health in the elderly.
292

Psychosocial factors and self-affirmation, in end-stage renal disease /

Estevez, Ryan Felipe. January 1900 (has links)
Thesis (Ph.D.)--Tufts University, 2002. / Adviser: Julio Garcia. Submitted to the Dept. of Psychology. Includes bibliographical references (leaves 65-73). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
293

Monitoring principles for haemodialysis /

Andersson, Roger, January 2002 (has links) (PDF)
Diss. Linköping : Univ., 2002.
294

Pharmacokinetic investigations into the metabolism and renal handling of organic cationic and anionic drug substances : studies with triamterene and its metabolites /

Muirhead, Murray R. January 1988 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept of Clinical and Experimental Pharmacology, 1988. / Spine title: Pharmacokinetic investigations of triamterine and its metabolites. Erratum slip inserted. Includes bibliographical references (leaves 227-239).
295

Mathematical modeling of renal autoregulation : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Bioengineering, University of Canterbury, Centre for Bioengineering, Department of Mechanical Engineering /

Kleinstreuer, Nicole C. January 2009 (has links)
Thesis (Ph. D.)--University of Canterbury, 2009. / Typescript (photocopy). Includes bibliographical references (p. 165-175). Also available via the World Wide Web.
296

The economic burden of end-stage renal disease in Canada: present and future /

Zelmer, Jennifer. January 2005 (has links)
Thesis (Ph.D.)--McMaster University, 2005. / Includes bibliographical references (p. 155-185). Also available online.
297

PERCEPÇÃO DE PACIENTES EM HEMODIÁLISE FORA DA LISTA DE ESPERA SOBRE O TRANSPLANTE RENAL / PERCEPTION OF PACIENT IN HEMODIALYSIS OFF THE WAITING LIST TO RENAL TRANSPLANT

Pauletto, Macilene Regina 18 January 2013 (has links)
It is a qualitative search, performed with 15 patients in hemodialysis which have indication to kidney transplant and are off the waiting list, they are patients in a renal clinic in Rio Grande do Sul State, Brazil. The objectives was: describe the perception of patients with indication to renal transplant that are off waiting list about the disease and the dialysis treatment; describe the perception of those patients about the transplant; and, to know the reasons that influence the patients in hemodialysis, with indication to renal transplant, about come not in waiting list. The rules of Resolution 196/96 of Health National Council, Health Department to searches involving human beings were respected. The data collection happened between March and July 2012 through narrative interview of experience. The data was submitted to content thematic analysis. The categories arising of data analysis are to describe and discuss in three articles that compound these study. The first one approaches the perception of patients about the disease and treatment of hemodialysis and resulted in the categories: the discovery of renal disease; changes and limitations of hemodialysis; and, the adaptation to treatment. The analysis of the categories can verify that even though limitation caused by disease and treatment, the patients feel safe and adapted to conditions of life in hemodialysis, and they remain in therapy although with indication to transplant. The second article is about perception of patients about transplant as a treatment that needs cares with possibility of complications, including death. Also, the perceptions about transplant are linked with success histories and the possibility of a new life out of machines. The perception of patients that the transplant is a treatment that demands cares, with possibility of complications, seems to influence in current decision of not come in the list, for implicate in changes and limitations in daily life, for which, the respondents are not prepared. The perception that transplant means a possibility of a new life free of hemodialysis machines, could contribute to consider the therapeutic modality. The third article presents the reasons to do not ingress in the waiting list, which were related with the need of medicines; financial implications and difficulties to ingress in list; uncertainty and negative experiences of transplant; possibilities of complications and return to hemodialysis; and, fear of death. Despite the listed reasons been relevant to do not ingress in waiting list, the need of being informed and clarified about the therapeutics is not discarded. It is important to nursing to know the perception of patients about the disease, treatment and possibility to kidney transplant, as well the reasons that influence to do not choose the renal transplant, with the objective of to orientate educative actions that could to guide, to clarify and respect the choices of patients. / Trata-se de uma pesquisa qualitativa, realizada com 15 pacientes em hemodiálise, com indicação para transplante renal, que estavam fora da lista de espera, de uma clínica renal, no interior do Rio Grande do Sul, Brasil. Os objetivos foram: descrever a percepção de pacientes com indicação para transplante renal que estão fora da lista de espera sobre a doença e o tratamento de hemodiálise; descrever a percepção de pacientes com indicação para transplante renal que não estão na lista de espera sobre o transplante; e, conhecer os motivos que influenciam os pacientes em hemodiálise, com indicação para transplante renal, em não ingressar na lista de espera. Foram respeitadas as normas da Resolução 196/96 do Conselho Nacional de Saúde do Ministério da Saúde para pesquisas envolvendo seres humanos. A coleta dos dados ocorreu de março a julho de 2012, por meio da entrevista narrativa de vivências. Os dados foram submetidos à análise de conteúdo temática. As categorias oriundas da análise dos dados são descritas e discutidas em três artigos, que compõem o presente trabalho. O primeiro artigo, que aborda a percepção dos pacientes sobre a doença e o tratamento de hemodiálise resultou nas categorias: a descoberta da doença renal; mudanças e limitações na vida de pacientes em hemodiálise; e a adaptação ao tratamento de hemodiálise. Com a análise destas categorias pode-se verificar que mesmo com as limitações provocadas pela doença e tratamento, os pacientes sentem-se seguros e adaptados às condições da vida em hemodiálise, de modo a permanecer nesta terapia mesmo possuindo indicação para transplante. O segundo artigo, que trata sobre as percepções dos pacientes sobre o transplante, apresenta-o como um tratamento que exige cuidados, com possibilidade de complicações, inclusive de morte. As percepções sobre o transplante também estão vinculadas a histórias de sucesso e a possibilidade de uma nova vida fora das máquinas. A percepção dos pacientes de que o transplante é um tratamento que exige cuidados, com possibilidade de complicações, parece influenciar na decisão atual de não ingressar em lista, por implicar em mudanças e limitações na vida diária, para as quais, os pesquisados ainda não estão preparados. A percepção de que o transplante representa a possibilidade de uma nova vida fora das máquinas de hemodiálise, pode contribuir para reflexões em considerar esta modalidade terapêutica. O terceiro artigo apresenta os motivos para não ingressar em lista de espera, os quais foram relacionados a necessidade de medicações; implicações financeiras e dificuldades para ingressar na lista; incertezas e experiências negativas do transplante; possibilidade de complicações e de retorno à hemodiálise; e, medo da morte. Apesar dos motivos elencados pelos pacientes serem relevantes para o não ingresso em lista de espera, não se descarta a necessidade de serem informados e esclarecidos, sobre esta terapêutica. Considera-se importante a enfermagem conhecer a percepção destes pacientes acerca de sua doença, tratamento e possibilidade de transplante renal, bem como os motivos que influenciam em não optar pelo transplante renal, no intuito de direcionar ações educativas que possam orientar, esclarecer e respeitar as escolhas dos pacientes.
298

Efeito da administração intraperitonial de glicerol sobre parâmetros bioquímicos e estruturais em rim de ratos jovens

Rieger, Elenara January 2011 (has links)
O glicerol é um agente osmótico utilizado para o tratamento da hipertensão intracraniana, edema cerebral e glaucoma. O glicerol também é usado experimentalmente para induzir insuficiência renal aguda através da rabdomiólise. Neste modelo, a administração intramuscular de glicerol provoca injúria nos túbulos renais devido a uma combinação de fatores que incluem vasoconstrição renal, obstrução dos túbulos contorcidos distais por cilindros de mioglobina e estresse oxidativo mediado pelos grupos heme da mioglobina. No entanto, segundo a literatura, o mesmo dano renal também é causado após a administração intraperitoneal de glicerol, sugerindo que este composto possa provocar insuficiência renal aguda através de mecanismos que não envolvam a rabdomiólise. Portanto, o objetivo deste estudo foi investigar os efeitos da administração intraperitoneal de glicerol durante 14 dias sobre parâmetros histológicos e bioquímicos no rim de ratos jovens. Foram utilizados ratos Wistar de 23 dias de idade e administrado intraperitonealmente uma solução hipertônica de glicerol (50% vol/vol) na dose de 10 mL/Kg de peso corporal durante 14 dias e os ratos controle receberam igual volume de solução salina (NaCl 0,85 g%). O dano renal foi avaliado através dos níveis plasmáticos de creatinina, atividades da creatina cinase e da lactato desidrogenase, e no rim foi realizada histologia, e mensurados a taxa de consumo de glicose, atividades das enzimas creatina cinase, piruvato cinase e lactato desidrogenase e alguns parâmetros de estresse oxidativo. O glicerol não alterou a atividade da creatina cinase plasmática e aumentou os níveis de creatinina no plasma, sugerindo insuficiência renal aguda e ausência de rabdomiólise. Houve redução na taxa de oxidação da glicose pelo rim, e das atividades da creatina cinase citoplasmática e mitocondrial, sugerindo redução da homeostasia energética no rim. Houve aumento na formação de radicais livres, lipoperoxidação e carbonilação de proteínas, sugerindo estresse oxidativo. As alterações histológicas e a redução do peso do rim foram compatíveis com necrose tubular. Os resultados são similares e mais severos que os descritos após uma única administração intramuscular, de glicerol. Portanto, pode ser importante avaliar a função renal em pessoas que fazem uso a longo prazo de glicerol. / Glycerol is osmotic agent used for the treatment of intracranial hypertension, cerebral oedema and glaucoma. Glycerol is also used experimentally to induce acute renal failure by rhabdomyolysis. In this model, intramuscular injection of glycerol causes renal tubular damage due to a combination of factors that include renal vasoconstriction, obstruction of distal convoluted tubules by myoglobin casts and oxidative stress mediated by heme groups of myoglobin. However, according to the literature, the same kidney damage occur after intraperitoneal administration of glycerol, suggesting that this compound may cause acute renal failure through mechanisms that do not involve rhabdomyolysis. The aim of this study was to investigate the effects of intraperitoneal glycerol for 14 days on histological and biochemical parameters in the kidney of young rats. Were used twenty-three-day-old Wistar rats its received an intraperitoneal injection of hypertonic glycerol (50% v/v) at a dose of 10 mL/kg body weight for 14 days and the control group received an equal volume of saline solution (NaCl 0.85g%). Renal damage was evaluated by plasma levels of creatinine, creatine kinase activity and lactate dehydrogenase, and kidney histology was performed, and measured the rate of glucose consumption, enzyme activities of creatine kinase, pyruvate kinase and lactate dehydrogenase and some oxidative stress parameters. Glycerol did not alter creatine kinase activity and increased plasma levels of creatinine, suggesting acute renal failure and absence of rhabdomyolysis. There was a reduction in the rate of oxidation of glucose by the kidney and the activities of cytoplasmic and mitochondrial creatine kinase, suggesting reduction of energy homeostasis in the kidney. Increase in the formation of free radicals, lipid peroxidation and protein carbonylation, suggesting oxidative stress. Histological changes and reduction in kidney weight were consistent with tubular necrosis. The results are similar and more severe than those reported after a single intramuscular administration of glycerol. So it seems that it would be important to evaluate renal function in people on long-term use of glycerol.
299

Vitamina e sua relação com o hiperparatireoidismo secundário na doença renal cronica pre-dialítica / Adequate 25-hydroxyvitamin D levels do not prevent secondary hyperarathyroidism in predialysis chronic kidney disease patients

Kubo, Andrea Higa [UNIFESP] January 2006 (has links) (PDF)
Made available in DSpace on 2015-12-06T23:44:27Z (GMT). No. of bitstreams: 0 Previous issue date: 2006 / Introdução: A vitamina D desempenha um importante papel na homeostase do cálcio e fósforo e, intervenções específicas são recomendadas nos vários estágios da doença renal crônica, a fim de se evitar ou postergar o aparecimento do hiperparatireoidismo secundário. Além da 1,25¬ dihidroxivitamina D a forma mais ativa da vitamina D; a 25-hidroxivitamina D seu precursor hepático, também tem tido destaque como participante dos mecanismos fisiopatológicos no desenvolvimento do hiperparatireoidismo secundário. O objetivo desse estudo foi avaliar a distribuição dos níveis de 25¬ hidroxivitamina D nos diferentes estágios da doença renal crônica e o possível papel dessa vitamina no metabolismo mineral de pacientes na fase pré¬ dialítica. Material e Métodos: Através de corte transversal foram estudados 51 pacientes adultos, portadores de doença renal crônica na fase pré-dialítica. Para a análise, os pacientes foram distribuídos nos vários estágios da doença renal crônica, de acordo com a classificação do KDOQ/I, o que compreendeu os segundo, terceiro e quarto estágios. Foram estudados os seguintes parâmetros laboratoriais: albumina, bicarbonato, cálcio iônico, fósforo, fosfatase alcalina total, PTH-intacto, 25-hidroxivitamina D, 1,25-dihidroxivitamina D, clearance de creatinina e proteinúria de 24hs. Resultados: Dos 51 pacientes, 10 encontravam-se no estágio 2, 25 no estágio 3 e 16 no estágio 4 da doença renal crônica. De acordo com o KIDOQI, nenhum paciente tinha deficiência severa de 25-hidroxivitamina D « 5 ng/mL) e 28 pacientes (55 por cento) apresentavam níveis dentro dos valores-alvo (> 30 ng/mL)Cerca de 62 por cento dos pacientes tinham PTH intacto acima do recomendado para seu estágio de doença renal. Não foram observadas quaisquer correlações entre a 1,25-dihidroxivitamina D e outros parâmetros bioquímicos ou hormonais. Uma análise de regressão linear múltipla revelou o clearance de creatinina, o fósforo e a 25-hidroxivitamina D como os determinantes independentes do PTH. Conclusão: Este estudo encontrou uma alta prevalência de hiperparatireoidismo secundário em pacientes com doença renal crônica não¬ dialítica, com níveis relativamente adequados de 25-hidroxivitamina D. Novos estudos serão necessários para determinar os reais valores-alvo desta vitamina na doença renal crônica em sua fase pré-dialitíca / BV UNIFESP: Teses e dissertações
300

Validação de conteúdo das características definidoras do diagnóstico de enfermagem proteção ineficaz em pacientes em tratamento hemodialítico / Validation of the defining characteristics of the ineffective protection nursing diagnosis in patients under hemodialytic treatment

Capellari, Claudia January 2007 (has links)
Os Diagnósticos de Enfermagem (DE) tem sido utilizado mundialmente como base para as intervenções de enfermagem. Para dar conta de sua adaptação às diversas realidades, estudos de validação são realizados e, dentre os métodos utilizados para tal, está o de Validação de Conteúdo Diagnóstico. Na área Nefrológica e, em especial, para os sujeitos que realizam hemodiálise, os diagnósticos são uma importante ferramenta para que se possa identificar as necessidades individuais e planejar o cuidado. O presente constitui-se de um estudo descritivo e transversal, em uma perspectiva quantitativa, com o objetivo de validar as Características Definidoras do DE Proteção Ineficaz em pacientes em tratamento hemodialítico, por enfermeiros peritos dos Centros de Diálise do Rio Grande do Sul, Brasil, cadastrados na Sociedade Brasileira de Nefrologia. Os dados foram coletados no período de outubro de 2006 a janeiro de 2007. A população constituiu-se de 139 enfermeiros e, da amostra, fizeram parte 63 enfermeiros, de 31 centros de diálise. Para a delimitação da amostra, foi utilizado o método de seleção de peritos, adaptado de Fehring (1987), congregado a amostragem não probabilística proposital. A coleta de dados ocorreu por meio de um instrumento, no qual constavam dados do participante, além de uma escala Likert para que se atribuísse valor de 1 a 5 (de menos para mais característico) a cada característica definidora. Às 18 características definidoras do DE Proteção Ineficaz foi acrescentada, como sugestão da pesquisadora, a característica Desnutrição, devido à sua importância na doença renal crônica. Como resultados, foram obtidos 5 Indicadores Principais Provisórios, com média ponderada ≥0,80, quais sejam: Deficiência na Imunidade, Alteração Neurossensorial, Dispnéia, Prurido e Desnutrição. Os Indicadores Secundários Provisórios foram: prejuízo na cicatrização, fraqueza, alteração na coagulação, resposta mal-adaptada ao estresse, fadiga, anorexia, insônia, desorientação, calafrios, tosse, perspiração, agitação e imobilidade. A característica úlceras de pressão foi excluída por obter escore ≤0,50. Concluiu-se que as características apontadas como Indicadores Principais são relacionados com a doença renal crônica e podem conduzir ao DE Proteção Ineficaz nos sujeitos que realizam hemodiálise, servindo de base para as intervenções de enfermagem. / The nursing diagnosis (ND) have been used worldwide as basis for nursing interventions. In order to suit them to more than one reality, validation studies are done and among several ones used for such purposes there’s the one called Diagnostic Content Validation. In the nephrologic area and in special for those patients who go through hemodialysis, the diagnosis are an important tool so that the individual needs can be identified as well as the care planning. The present study is made of a descriptive and transversal way, in a quantitative perspective with the goal of validating the defining characteristics of the nursing ineffective protection diagnosis in patients under hemodialytic treatment. The study was made by master nurses of the Rio Grande do Sul Dialysis Centers who are also registered in the Brazilian Nephrology Society. The data was searched from October/2006 up to January/2007. There are 139 nurses in this study and on the sampling, there were 63 nurses from 31 Dialysis centers. For the sample delimitation, the experts selection method was used, adapted from Fehring (1987), along with the intentional non-probabilistic sampling one. The data search happened through an instrument in which there were the participant’s data. Besides that, there was a Likert scale so that values from 1 to 5 (from least to most characteristic) could be given to each one of the defining characteristics. As a suggestion from the searcher, one characteristic was added to the 18 defining ones of the ineffective protection nursing diagnosis. It’s the malnutrition due to its importance in the chronic kidney disease. 5 temporary main indexes were obtained as results with an average of ≥ 0,80. The results are: Immunity Deficient, Neurossensory Alteration, Dyspnea, Itching and Malnutrition. The temporary secondary indexes were: impaired healing, weakness, altered clotting, maladaptive stress response, fatigue, anorexia, insomnia, disorientation, chilling, cough, perspiring, restlessness and immobility. The ulcer pressure characteristic was excluded for obtaining score ≤0,50. It was concluded that the characteristics listed as main indexes are related to the chronic kidney disease and can lead to the ineffective protection nursing diagnosis in those patients who go through hemodialysis serving as basis for nursing interventions.

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