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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.
151

Identifying Optimal Electron Donors to Promote Biosequestration of Uranium for an UMTRCA Title 1 Site

Abel, Erin Jessica, Abel, Erin Jessica January 2016 (has links)
Biostimulation is the use of in-situ microorganisms and added reagents in order to biosequester, precipitate, or absorb contaminants from contaminated groundwater and sediment. To test the effectiveness of this remediation approach at a particular site, small scale experiments, such as miscible-displacement, batch, or microcosm experiments, should be performed before a large-scale in-situ biosequestration electron donor injection. In this study, electron donor solutions containing contaminated groundwater and ethanol, acetate, benzoate, or glucose were injected into aquifer sediments collected from a UMTRCA Title 1 Site in Monument Valley, AZ. These experiments showed that ethanol, acetate, and glucose were effective electron donors for the stimulation of microbial activity in order to sequester uranium and reduce nitrate and sulfate concentrations. Conversely, benzoate was not effective at sequestering or reducing the contaminants. After electron-donor deficient groundwater was injected into the columns, a rebound of nitrate, sulfate, and uranium concentrations was observed. Due to this rebound, it was inferred that the mechanism of sequestration of uranium and hence reduction of nitrate and sulfate was due to the creation of reducing conditions via microbial activity. The insoluble reduced uranium was hypothesized to have precipitated or adsorbed to surrounding sediments. Incoming groundwater contained dissolved oxygen and therefore oxidized the reduced contaminants, consequently returning them into solution. It was hypothesized that a similar rebound would occur if ethanol, acetate, or glucose were to be injected in-situ due to sustained groundwater flow through the aquifer sediments on site.
152

Synthesis and characterisation of dithiolato complexes with platinum group metals

Morton-Fernández, Brian January 2013 (has links)
The interest in biosensors can be attributed to the first described enzyme containing sensor used to detect levels of glucose in 1962. Although research into biosensors was initially slow to pick up, the field has become increasingly popular and research has been widespread for the last 20 years. The continuing research into biosensors is crucial as this will improve current devices to become smaller, faster and more economical and yield new biosensors. This thesis is mostly concerned with the development of an integral component of a biosensor, the redox mediator. Complexes of ruthenium incorporating electron rich sulfur-donor ligands such as naphthalenedithiol should possess interesting redox qualities which could be used to produce better mediators. A second area covered in this thesis is in the structural studies of a series of iridium and rhodium complexes. Two classes of ruthenium complexes with sulfur-donor ligands have been prepared. The first class incorporates the ruthenium bis-bipyridine moiety while the second contains pentamethylcyclopentadienyl ruthenium. Most complexes synthesised exhibited reversible oxidation waves in the region of -0.1 to 0.2 V vs. Ag/Ag⁺. Their possible use as redox mediators was hindered by several factors, particularly difficulties in purification. They also exhibited oxygen sensitivity and low stability when in solution.The second area covered in this thesis is to further understand the bonding of the ligands used in the above study. A series of pentamethylcyclopentadienyl iridium and rhodium complexes were synthesised with three different dithiolato ligands. Two of the three ligands studies produced structures that included more than one metal centre leading to straining of the ligand. In order to study the monomeric form, the clusters were opened with a neutral phosphine ligand. Both the Ir…S and Rh…S bond lengths of all the complexes were within expected parameters.
153

Interpersonal and Shared Decision Making models of communication applied to simulated requests for organ donation

Baughn, Daniel 30 April 2009 (has links)
Using an analogue format, the present study evaluated the viability of relationship and interactional concepts that have been applied to the physician-patient interaction to the field of organ donation by examining the donation request process between procurement coordinators and simulated families. Interpersonal processes were assessed using behavioral ratings by independent observers. Procurement coordinators were viewed as being more submissive than dominant and more friendly than hostile. Family members were viewed as being more hostile than friendly, more dominant and hostile than submissive or friendly, disclosing slightly more personal information than medical information, and engaging in slightly more shared decision making than providing medical information. Procurement coordinator gender and ethnicity and family ethnicity influenced interpersonal behavior. Several interpersonal variables were associated with measures of the “decision to donate” obtained from raters and simulated families. Implications for the field of organ donation and the training of procurement coordinators are discussed.
154

Obésité et infarctus du myocarde : effets de l'exercice musculaire régulier et d'un donneur de CO / Obesity and myocardial infarction : effects of regular treadmill exercice and a CO-donor

Portal, Lolita 13 December 2013 (has links)
L'infarctus du myocarde (IDM) est l'une des principales causes de morbi-mortalité dans le monde et ce malgré une revascularisation rapide de l’artère coronaire occlue. L'obésité est un facteur de risque majeur pour l’IDM, et concerne 15 % de la population française (enquête ObEpi-Roche/INSERM, 2012). L'objectif de notre étude a été d'étudier l'efficacité de stratégies cardioprotectrices comme l’exercice physique chronique ou l’administration d’un donneur de CO (CORM-3) dans un contexte d’obésité. Un effet cardioprotecteur de l'exercice physique chronique a été démontré sur un modèle d’ischémie-reperfusion chez la souris ob/ob (génétiquement dépourvu en leptine). Cet effet implique l’activation de la voie de signalisation cardioprotectrice RISK associée à une diminution des taux cytosoliques des protéines phosphatases inhibitrices correspondantes PTEN et MK3P ce qui aboutit à une amélioration des fonctions mitochondriales. Ce travail montre la capacité différentielle de stratégies à réduire la taille de l’infarctus en cas d’obésité. Par ailleurs, il souligne l’importance du rôle des mécanismes HCO3- dépendants dans le contrôle du pH intracellulaire à la reperfusion. Ils pourraient représenter une étape clef dans la cardioprotection. / Myocardial infarction (MI) remains the leading cause of morbidity and mortality in the developing countries despite significant therapeutic advances over the last years. Obesity is a major risk factor for coronary heart disease and concern 15% of the French population (ObEpi-Roche/INSERM survey, 2012). The aim of our studie was to investigate the efficacy of cardioprotective strategies such as regular treadmill exercice or CO donor administration (CORM-3) against MI during obesity. In ob/ob mice, regular exercise induces a robust cardioprotection by increasing kinase phosphorylation of RISK pathway, decreasing levels of corresponding phosphatases and improving the resistance of mitochondrial permeability transition pore opening. The present study shows differential capabilities of cardioprotective strategies at reducing myocardial infarct size with obesity. In addition, it underlines the role of HCO3- dependent mechanisms in the control of intracellular pH at reperfusion. They could represent a key step for mediating cardioprotection.
155

Foreign aid and governance : to what extent political institutions matter / Aide au développement et gouvernance

Gary, Aurore 18 December 2014 (has links)
L’efficacité de l’aide au développement est aujourd’hui largement débattue au sein de la communauté des donateurs et dans la littérature académique (Rajan and Subramanian, 2008). Le contexte institutionnel des pays récipiendaires est au cœur de ce débat puisqu’il conditionnerait l’efficacité de l’aide en termes de croissance économique (Dalgaard and Hansen (2001), Collier and Dollar (2002) and Burnside and Dollar, 2004). L’aide serait efficace dans les pays pauvres et bien gouvernés. L’objet de ce travail de recherche est d’expliquer l’apparition de critères institutionnels dans l’allocation de l’aide au développement et de déterminer leurs effets en matière d’efficacité de l’aide. Il vise donc à appréhender le rôle joué par la gouvernance dans les pays receveurs (pays en développement) et dans les pays donateurs (pays de l’OCDE essentiellement) à la fois dans l’allocation et dans l’efficacité de l’aide au développement. Ce travail tente donc de répondre à plusieurs interrogations : (1) la reconnaissance de la nature institutionnelle de l’aide est-elle appropriée ? (2) l’aide est-elle- intrinsèquement politique ? (3) quelles sont les implications économiques de l’aide allouée selon des critères institutionnels ? / The recognition that political institutions matter is relatively recent and is the result of several interacting factors. The purpose of our research is to explain how foreign aid is related to governance issues both in recipient countries (developing countries) and in donor countries. Development aid is provided by: bilateral donors (29 DAC3 donors and 19 non-DAC donors), multilateral donors and private donors (e.g. Bill & Melinda Gates Foundation). Foreign aid differs according to the intended purposes: reforming national policies (economic policies or other types) and political institutions, and providing humanitarian assistance. The focus of our dissertation is on the emergence of non-strictly economic criteria (mainly institutional criteria) within the donor community as well as their impact on aid allocation and effectiveness. Therefore, we will address several questions: (1) Is the recognition of the institutional nature of aid appropriate?(2) Is aid political? (3) What are the economic implications of political aid (or aid based on institutional performance) ?
156

Current Views on Creating Families: Adoption, Assisted Reproduction and Family Relationships

Weiss, Allison R January 2003 (has links)
Thesis advisor: Diane Scott-Jones / The purpose of this study was to explore young adults' views on building their future families; methods of having children including adoption, in vitro fertilization (IVF), donor insemination, egg donation, and surrogacy; disclosure of these methods to children; and the importance of children's contact with extended family. The sample consisted of 82 Boston College students, 41 males and 41 females, with a mean age of 20.67 years. Participants completed a questionnaire and an open-ended interview. The majority of the participants expected to have a life-long partner, raise at least one child, and help their children build relationships with extended relatives. Males and females did not differ on most questions; however females reported thinking about their future families more often than did males (p = .01), and females expected to start their families earlier than did males (p = .02). Participants were more open to adoption than to assisted reproduction technology (ART). IVF was the most preferred among the methods of ART (p < .001). Participants reported they would be most likely to disclose information to their child had they used adoption or ART and were the genetic parent. Some participants emphasized the importance of disclose to a child had they used ART and were not the genetic parents; approximately one-fourth of participants affirmed that a child has a right to know. Participants reported it would be easier to answer their children's questions about adoption or ART than to initiate a discussion on these topics with their children (p < .001). The majority of participants reported that it was important to help their children build connections with extended family and they planned to accomplish this through visiting and preserving family traditions. The findings provide insight into young adults' expectations for creating their families. / Thesis (BA) — Boston College, 2003. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Psychology. / Discipline: College Honors Program.
157

Avaliação de algumas estratégias para o uso de metano como doador de elétrons na desnitrificação / Evaluation of strategies to methane application as electron donor in denitrification process

Costa, Rachel Biancalana 02 September 2016 (has links)
O principal objetivo deste trabalho foi a avaliação de estratégias que viabilizassem o uso do metano como doador de elétrons para desnitrificação em ambiente anóxico, visando à aplicação de tecnologia para pós-tratamento de efluente de reatores de manta de lodo e fluxo ascendente &#40;UASB&#41; aplicado no tratamento de esgoto sanitário. O trabalho foi dividido em cinco etapas, sendo que em todas elas o metano foi fornecido como única fonte de carbono orgânico. Na Etapa 1, foram comparados dois inóculos, em reatores em batelada sequenciais &#40;SBR&#41; com biomassa imobilizada. Como inóculo, foi utilizada mistura de sedimento marinho e sedimento de mangue &#40;SED-SBR&#41; ou lodo de reator UASB &#40;LAn-SBR&#41;. Na Etapa 2, foram avaliadas estratégias de enriquecimento da comunidade metanotrófica desnitrificante. Para tanto, foram operados dois SBRs: um com biomassa imobilizada &#40;Imob-SBR&#41; e outro com biomassa suspensa &#40;Susp-SBR&#41;. Na Etapa 3, foi operado reator contínuo de leito fixo e estruturado e fluxo ascendente &#40;Up-FSBR&#41;. Nas etapas 1 e 3, o metano suportou a ocorrência da desnitrificação e da manutenção celular. O consumo das formas nitrogenadas na Etapa 2 foi muito baixo e não foi possível concluir qual a melhor estratégia para enriquecimento da biomassa. Na Etapa 4, a biomassa retirada do Up-FSBR ao final da operação foi submetida a testes de endogenia. Foram operadas bateladas simples e, em cada uma, foi dosada apenas uma das formas nitrogenadas em condições com metano e sem metano. Os resultados mostraram que a redução das formas nitrogenadas é um processo paralelo à oxidação de metano. Na Etapa 5, foi avaliado o consumo de metano e de nitrato em SBR com biomassa suspensa em condições microaeradas e anóxicas. Foi observado que tanto a oxidação do metano quanto a redução do nitrato ocorrem em maior intensidade quando expostos a condições de microaerofilia. A análise dos resultados obtidos permite concluir que os organismos responsáveis pela redução de nitrato &#40;MD&#41; estabeleceram uma relação sintrófica com as bactérias oxidadoras de metano &#40;MM&#41;. Observou-se que, quando as bactérias oxidadoras de metano foram estimuladas, a desnitrificação ocorreu em maior intensidade. / This work aimed to develop the methane &#40;CH4&#41; application as electron donor to denitrification under anoxic conditions for post-treatment of Upflow Anaerobic Sludge Blanket &#40;UASB&#41; effluent, applied in sewage treatment systems. The study was conducted in five stages, in which methane was provided as the sole organic carbon source. In Stage 1, methanotrophic denitrification was assessed in Sequencing Batch Reactors &#40;SBR&#41; inoculated with a blend of marine and mangrove sediments &#40;SED-SBR&#41; or anaerobic sludge &#40;LAn-SBR&#41;. For both inocula. In Stage 2, strategies for the enrichment of methanotrophic-denitrifying community were evaluated. Two SBRs were operated: in one of them, biomass was immobilized &#40;Imob-SBR&#41; while the other was inoculated with suspended biomass &#40;Susp-SBR&#41;. In Stage 3, methanotrophic denitrification was addressed in an Upflow Fixed-Structured Bed Reactor &#40;Up-FSBR&#41;. In Stages 1 and 3, methane supported denitrification and cellular maintenance. In Stage 2, the consumption of oxidized nitrogen compounds was too low, and it was not possible to conclude which is the better strategy for enrichment of the methanotrophic-denitrifying community. In Stage 4, the biomass withdrawn from Up-FSBR was subjected to endogeny tests, in batch reactors. In each batch reactor, only nitrite or nitrate was provided, and both methane and methane-free conditions were tested. It was observed that nitrite and nitrate reduction occurred as a marginal process. In Stage 5, methane oxidation coupled to denitrification was assessed under both anoxic and microoxic conditions and both processes were stimulated under the latter. The obtained data suggest denitrifiers established a syntrophic relationship with methane-oxidizers, and when the latter was stimulated, the denitrification also occurred in greater extent.
158

Investigação da prevalência de anticorpos irregulares em doadores de sangue do Instituto Paranaense de Hemoterapia e Hematologia Ltda / Investigation of the prevalence of irregular antibodies in blood donors of the Instituto Paranaense de Hemoterapia e Hematologia Ltda

Koury, Wallyd Kalluf 08 June 2018 (has links)
Anticorpos antieritrocitários são produzidos contra um ou mais epítopos presentes na superfície dos glóbulos vermelhos. A pesquisa de anticorpos irregulares consiste em expor os anticorpos circulantes do indivíduo a antígenos conhecidos in vitro. Nos casos dos doadores de sangue, a legislação vigente determina a realização da pesquisa de anticorpo irregular (PAI), não exigindo, porém, a determinação da especificidade do anticorpo, e os componentes plasmáticos e os concentrados de plaquetas, cuja presença de anticorpos irregulares fora evidenciada, não devem ser utilizados para transfusão. O presente estudo caracterizou o perfil imunohematológico referente à presença de anticorpos irregulares em doadores de sangue do Instituto Paranaense de Hemoterapia e Hematologia Ltda., no período de abril de 2008 a dezembro de 2015, e avaliar: (i) a prevalência de doadores de sangue voluntários que apresentam PAI positiva, (ii) a especificidade dos aloanticorpos identificados, (iii) a prevalência dos aloanticorpos em doadores de acordo com o sexo e a faixa etária. O projeto de pesquisa foi aprovado pelo Comitê de Ética em Pesquisa. As informações sobre resultado da PAI, especificidade do anticorpo, sexo e idade disponíveis no sistema informatizado do Instituto Paranaense de Hemoterapia e Hematologia Ltda. foram acessadas. As análises estatísticas foram realizadas utilizando-se o teste exato de Fisher e valores de p<0,05 foram considerados estatisticamente significativos. Foram analisados 155.834 doadores. Em 474 (0,3%) doadores foram detectados anticorpos irregulares, dos quais, 358 doadores apresentaram resultados conclusivos (25% sexo masculino e 75% feminino). Os anticorpos de maior frequência foram anti-D (23%, n=83), anti-M (15%, n=55), anti-K (12,2%, n=44), anti-E (11,7%, n=42) e antiDia (11,7%, n=42). As associações de diferentes anticorpos ocorreram em 14,8% (48) da população estudada, sendo a mais frequente, anti-D + anti-C (n=19). A frequência de anticorpo irregular na população feminina foi significativamente maior que na masculina para as especificidades anti-D (p=0,0191) e anti-M (p=0,0005). O grupo de doadores com idade menor a 40 anos apresentou uma frequência estatisticamente maior de anticorpos irregulares com especificidades anti-M (p=0,0008) e anti-Dia (p=0,0176) quando comparado ao grupo de doadores com idade maior ou igual a 40 anos. Entre os 86 doadores do sexo masculino, a prevalência de anti-Dia foi significativamente maior na população masculina com idade inferior10 a 40 anos quando comparado aos doadores com idade maior ou igual a 40 anos (p=0,0273). O resultado obtido induz a suspeita de um provável IgM de origem natural considerando que esta população de doadores masculinos apresenta baixa chances de aloimunização por transfusão e não tem histórico de gestacional. A definição da prevalência e especificidade de aloanticorpos em doadores de sangue pode indicar a necessidade de um protocolo que defina a conduta frente ao doador com objetivo de proteção do doador de sangue e otimização do serviço de hemoterapia em relação às coletas de sangue realizadas / Anti-erythrocyte antibodies are produced against one or more epitopes present on the surface of red blood cells. The search for irregular antibodies consists in exposing the subject\'s circulating antibodies to known antigens in vitro. In the case of blood donors, the current Brazilian legislation determines that the irregular antibody test (PAI) must be checked in all blood donores, but does not require the determination of the specificity of the antibody, and the plasma components and the platelet concentrates from blood donors with irregular antibodies should not be used for transfusion. The present study characterized the immunohematology profile for the presence of irregular antibodies in blood donors from the Instituto Paranaense de Hemoterapia e Hematologia Ltda., from April 2008 to December 2015, in order to evaluate: (i) the prevalence of donors with irregular antibodies, (ii) the specificity of the alloantibodies identified, (iii) the prevalence of alloantibodies in donors according to gender and age group. The research project was approved by the Ethics Committee. PAI result, antibody specificity, sex and age data were collected from the system of the Instituto Paranaense de Hemoterapia e Hematologia Ltda. Statistical analyzes were performed using Fisher\'s exact test and values of p <0.05 were considered statistically significant. A total of 155,834 donors were analyzed. In 474 (0.3%) donors, irregular antibodies were detected, of which 358 donors presented conclusive results (25% male and 75% female). The most frequent antibodies were anti-D (23%, n = 83), anti-M (15%, n = 55), anti-K (12.2%, n = 44), anti-E (7%, n = 42) and anti-Dia (11.7%, n = 42). The associations of different antibodies occurred in 14.8% (48) of the study population, being the most frequent anti-D + anti-C (n = 19). The frequency of irregular antibody in the female population was significantly higher than in the male for the anti-D (p = 0.0191) and anti-M (p = 0.0005) specificities. The group of donors less than 40 years of age presented a statistically higher frequency of irregular antibodies with anti-M (p = 0.0008) and anti-Dia specificities (p = 0.0176) when compared to the group of donors aged 40 years or older. Among the 86 male donors, the prevalence of anti-Dia was significantly higher in the male population under 40 years of age when compared to those aged 40 years or older (p = 0.0273). This result induces the suspicion of a probable IgM of natural origin considering that this population of male donors has low chances of transfusion alloimmunization and has no gestational history. The definition of the prevalence and specificity of alloantibodies in blood donors may indicate the need for a12 protocol that defines the conduct towards the donor for the purpose of protecting the blood donor and optimizing the hemotherapy service in relation to the blood collections performed.
159

Mecanismos celulares envolvidos no relaxamento da aorta de ratos induzidos pelo composto doador de óxido nítrico cis-[Ru(bpy)2(py)(NO2)](PF6)(RuBPY) / Cellular mechanisms involved in the rat aorta relaxation induced by the nitric oxide donor cis-[Ru(bpy)2(py)(NO2)](PF6) (RuBPY).

Pereira, Amanda de Carvalho 31 August 2011 (has links)
O óxido nítrico (NO) é o principal agente vasodilatador endógeno que regula o tônus e a homeostase vascular. Dentre os compostos doadores de NO, estão os complexos nitrosilos de rutênio. No presente estudo, o doador de NO estudado, RuBPY, não apresenta citotoxicidade para células do músculo liso vascular (MLV) ao contrário do NPS. O RuBPY apresenta eficácia semelhante ao NPS em relaxar o MLV de aorta de ratos, porém o NPS é mais potente. Ambos compostos liberam NO do tipo radicalar (NO) no meio intracelular, mas o NPS libera também íon nitroxil (NO-). O sequestrador da espécie NO (hidroxocobalamina) reduziu mais a resposta relaxante estimulada com RuBPY do que com o NPS. Nenhum dos dois compostos precisa ser reduzido quimicamente para liberar NO, uma vez que houve relaxamento quando utilizamos alta concentração de KCl como agente contrátil. Porém, este relaxamento foi inibido, o que mostra a importância dos canais para K+ no relaxamento induzido pelos doadores de NO. O bloqueador não seletivo de canais para K+ (TEA), inibiu somente o relaxamento ao RuBPY. A via NO-GCs-GK é ativada por ambos doadores de NO, para induzir relaxamento. A inibição da degradação do GMPc potencializou o relaxamento estimulado com RuBPY e NPS. O armazenamento de Ca+2 no retículo sarcoplasmático (RS) via ativação da SERCA é importante somente para o relaxamento induzido com RuBPY. O composto RuBPY inibiu a resposta contrátil estimulada com fenilefrina devido ao armazenamento de Ca+2 no RS e também por inibir o influxo capacitivo de Ca+2. A presença do endotélio vascular não alterou o relaxamento induzido pelo RuBPY, porém potencializou o relaxamento induzido pelo NPS. A análise da liberação de NO por amperometria demonstrou que o RuBPY libera NO somente em presença do tecido aórtico de ratos. Portanto, não houve liberação espontânea de NO, por fotólise pela luz visível ou por redução química. É necessária a presença de heme-proteínas como a guanilil-ciclase solúvel (GCs) inibida pelo ODQ, para haver a conversão do nitrito presente no RuBPY, a NO. Pela quantificação da fluorescência emitida pela sonda DAF-2DA, RuBPY liberou cerca de 3,5 vezes mais NO do que o NPS. Pela medida do potencial de membrana, demonstramos que o RuBPY induz hiperpolarização de membrana de células isoladas do MLV da aorta de rato. RuBPY tem efeito hipotensor dose-dependente, em ratos hipertensos renais, o que não ocorre em animais normotensos. A redução da pressão arterial em ratos hipertensos é maior do que nos normotensos. Em estudos iniciais de farmacocinética, verificamos que o composto RuBPY é absorvido por via oral e é distribuído entre alguns tecidos após ser administrado aos ratos, por gavagem. / Nitric oxide (NO) is the main endogenous vasodilator agent that regulates vascular tone. Among the compounds which are able of releasing NO, are the nitrosyl ruthenium complexes. The NO donor studied, RuBPY, does not present cytotoxicity in smooth muscle cells (SMC), in contrast to SNP. RuBPY has similar efficacy to SNP in inducing rat aorta relaxation, although SNP is more potent. Both compounds release intracellular radicalar NO (NO), and SNP also release ion nitroxyl (NO-). The NO scavenger (hydroxocobalamine) had greater effect on the relaxation induced by RuBPY than by SNP. Both compounds do not need to be chemically reduced to release NO, as demonstrated in aorta relaxation after pre-contraction with high concentrations of KCl. However, this relaxation was impaired, showing the importance of K+ channels to induce relaxation by NO released from these compounds. By using non-selective blocker for K+ channels (TEA), only the relaxation induced by RuBPY was inhibited. The NO-sGC-GK pathway is activated by NO donors to induce relaxation. Inhibition of cGMP degradation, potentiated the effect of RuBPY and SNP. Storage of Ca+2 in the sarcoplasmic reticulum (SR) via activation of SERCA is important only for the relaxation induced by RuBPY. The contractile response induced by phenylephrine was inhibited by RuBPY due to the storage of Ca+2 in RS and also by inhibiting the capacitive influx of Ca+2. The presence of endothelium had no effect on the relaxation induced by RuBPY, but it potentiated the relaxation induced by SNP. RuBPY released NO only in the presence of the rat aorta. The complex RuBPY did not spontaneously release NO, by photolysis by visible light, or by chemical reduction. RuBPY requires the presence of heme-protein such as guanylyl-cyclase, inhibited by ODQ, to convert nitrite to NO. The amount of NO released from RuBPY was about 3.5 times greater than that released from SNP. RuBPY induced membrane hyperpolarization of SMC. RuBPY has hypotensive effect in renal hypertensive rats in a dose-dependent way, which does not occur in normotensive rats. The decreased of blood pressure in hypertensive rats was greater than in normotensive rats. Initial studies of pharmacokinetics demonstrated that RuBPY is orally absorbed and it is also distributed in some tissues after being administered by gavage to rats.
160

Sobrevida de alotransplante renal com doador cadáver relacionada à idade do doador, tempo de isquemia fria e compatibilidade HLA / Impact of aged donors, HLA compatibility and cold ischemia time on survival rate of cadaver renal transplantation.

Cassini, Marcelo Ferreira 03 April 2009 (has links)
Introdução: O transplante renal é amplamente reconhecido como a melhor forma de tratamento para os pacientes que necessitam de terapia de substituição renal, e isso o torna vítima de seu próprio sucesso. Apesar de ser considerado um triunfo clínico-cirúrgico, é igualmente uma fonte de frustração, pela carência de doadores de órgãos e pelo crescimento das listas de espera. Há necessidade do desenvolvimento de estratégias que tornem maior o número de rins disponíveis para transplante. A idade do doador, o tempo de isquemia fria (TIF) e o HLA (antígeno leucocitário humano de histocompatibilidade) são fatores que estão relacionados à sobrevida do enxerto e, desta forma, envolvidos na diminuição da demanda e no aumento da oferta de órgãos. Objetivos: Avaliar o impacto das variáveis, idade do doador, compatibilidade HLA e tempo de isquemia fria, na sobrevida do enxerto de pacientes submetidos à alotransplantes renais com doador cadáver. Materiais e Métodos: Foram analisados retrospectivamente 454 pacientes submetidos a transplantes renais com doadores cadáveres realizados de abril de 1987 a dezembro de 2003, no Hospital das Clínicas da Faculdade de Medicina de Ribeirão Preto da Universidade de São Paulo (HCFMRP-USP). Resultados: Das variáveis analisadas, a idade do doador foi a de maior impacto estatístico na sobrevida dos transplantes renais estudados. A sobrevida dos enxertos oriundos de doadores com idade de 16 a 40 anos (143,30 meses em média), foi significativamente maior em comparação com a sobrevida nos grupos com doadores acima de 40 anos (66,46 meses) (p= 0,005) e nos doadores de 0 a 10 anos de idade (63,29 meses) (p= 0,01). A compatibilidade HLA e o TIF não interferiram de modo significativo na sobrevida dos transplantes estudados (p= 0,98 e p= 0,16 respectivamente). Conclusões: O tempo de isquemia fria (TIF) e a compatibilidade HLA não apresentaram impacto na sobrevida dos transplantes renais analisados. Os doadores cadáveres com idade de 16 a 40 anos podem ser considerados ideais, uma vez que demonstraram, de modo estatisticamente significativo, impacto favorável na sobrevida dos rins por eles doados. / Introduction: Renal transplantation is world wide recognized as the best therapy for patients that need kidney substitution treatment. It can be considered a clinical and surgical triumph and at the same time, its a form of frustration by the few organs donations available and by the growth of the waiting lists. New strategies are needed to be developed to increase the numbers of kidneys for transplantation. Donors aged, cold ischemia time (CIT) and human leukocyte antigen (HLA) compatibility are correlated with graft survival and consequently, with a diminished organs demand. Objectives: To study the impacts of donors age, cold ischemia time and HLA compatibility, on graft survival patients submitted to cadaver kidney allograft transplantation. Materials and Methods: Records from 454 patients, submitted to cadaver kidneys allograft transplantations between April/1987 and December/2003 by Division of Urology of the Clinical Hospital of Ribeirao Pretos School of Medicine at Sao Paulo University, were analyzed. Results: The age of kidneys donors was the most statistically significant data in the survival graft rate. Donors between 16 and 40 years old had a median survival rate about 143.30 months, that was significantly higher when compared with aged donors above 40 years (66.46 months) (p= 0.005) and below 10 years old (63,29 months) (p= 0.01). In our study, HLA compatibility and cold ischemia time didnt have statistically significant impact on renal allograft survival rate (p= 0.98 and p= 0.16, respectively). Conclusions: HLA compatibility and cold ischemia time didnt have significantly impact on renal allograft survival rate. Donors between 16 and 40 years old can be considered the ideal donors age, since they demonstrated statistically a favorable impact on grafts survival rate.

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