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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

Étude des modifications structurales et fonctionnelles de l'albumine dans le diabète de type 2 : identification de biomarqueurs de glycoxydation et de facteurs de risque de complications vasculaires / No english title available

Guérin-Dubourg, Alexis 03 December 2014 (has links)
La mortalité du diabète de type 2 est liée à ses complications cardiovasculaires (CVD). L'identification de nouveaux biomarqueurs associés à la dysfonction endothéliale, permettrait d'en améliorer le dépistage, la prévention. Au cours du diabète de type 2, l'hyperglycémie est associée à un fort stress oxydant. Nous nous sommes proposés ici d'évaluer l'impact de la glycoxydation sur la principale protéine circulante, l'albumine, et d'identifier si les modifications glycoxydatives de l'albumine dans le diabète avait un rôle dans la phyiopathologie des CVD du diabète de type 2. Nous avons pu mettre en évidence des modifications structurales et fonctionnelles importantes de l'albumine au cours du diabète de type 2 avec la formation entre autres de produits avancés de glycation (AGEs). Ces modifications glycoxydatives sont associées à des effets cellulaires pro-oxydant et pro-inflammatoire via une augmentation de l'expression du Récepteur aux AGEs (RAGE). Ces observations suggèrent que les formes glycoxydées d'albumine présentent un rôle central dans les mécanismes menant à la dysfonction endothélilale. Il reste néanmoins à évaluer l'intérêt du dosage des formes modifiées de l'albumine dans le dépistage des CVD au cours d'une étude clinique prospective de grande ampleur. Le développement d'une méthode de dosage rapide et reproductible des fractions d'albumine modifiées, comme celui de l'IMA (albumine modifiée par l'ischémie), en faciliterait la mise en œuvre. / Type 2 diabetes is dramatically associated with an enhanced cardiovascular complication risk. The identification of novel biomarkers associated with endothelial dysfunction remains highly warranted to improve diabetes screening and prevention. Oxidative stress and protein modifications are frequently observed in numerous disease states. Albumin, the major circulating protein in blood, can undergo increased glycoxidation in diabetes. Objectives of my thesis were to clarify the impact of glycoxidative modification of albumin on its structure and its functions and to determine whether such impairments may be encountered in albumin purified from diabetics. The occurrence of oxidative modifications was found to be enhanced in in vitro glycoxidized HAS and albumin purified from diabetics, after determination of their free thiol group content, relative electrophoretic migration, carbonyl content, and antioxidant activities. In addition, glycoxidized albumin exhibited impaired pharmaceutic molecule binding capacities. Cells treated with glycoxidized albumin exhibited a proinflammatory state attested by an overgeneration of intracellular reactive oxygen species, enhancements in RAGE expression, and an accumulation of carbonylated proteins.Methods to detect IMA (ischemia modified albumin) were developed and applied to diabetics patients. Relationships have been established between specific pathological parameters (cardiovascular disorders, hyperglycemia…) with an enhanced glycoxidative modification of albumin in diabetics. We thus propose that impaired albumin structure and function in relation in the enhanced oxidant stress observed in diabetics might be involved in the increased mortality risk of these patients.
12

A prospective, randomized, single-blind study of intrasulcular mucosal anesthesia as an adjunct for anesthetizing the palatal mucosa of the maxillary first molar.

Charnas, Joseph Craig January 2021 (has links)
No description available.
13

Distribution d'une architecture modulaire intégrée dans un contexte hélicoptère / Distribution of an integrated modular architecture in a helicopter context

Bérard-Deroche, Émilie 12 December 2017 (has links)
Les architectures modulaires intégrées (IMA) sont une évolution majeure de l'architecture des systèmes avioniques. Elles permettent à plusieurs systèmes de se partager des ressources matérielles sans interférer dans leur fonctionnement grâce à un partitionnement spatial (zones mémoires prédéfinies) et temporel (ordonnancement statique) dans les processeurs ainsi qu'une réservation des ressources sur les réseaux empruntés. Ces allocations statiques permettent de vérifier le déterminisme général des différents systèmes: chaque système doit respecter des exigences de bout-en-bout dans une architecture asynchrone. Une étude pire cas permet d'évaluer les situations amenant aux limites du système et de vérifier que les exigences de bouten- bout sont satisfaites dans tous les cas. Les architectures IMA utilisés dans les avions centralisent physiquement des modules de calcul puissants dans des baies avioniques. Dans le cadre d'une étude de cas hélicoptère, ces baies ne sont pas envisageables pour des raisons d'encombrement: des processeurs moins puissants, utilisés à plus de 80%, composent ces architectures. Pour ajouter de nouvelles fonctionnalités ainsi que de nouveaux équipements, le souhait est de distribuer la puissance de traitement sur un plus grand nombre de processeurs dans le cadre d'une architecture globale asynchrone. Deux problématiques fortes ont été mises en avant tout au long de cette thèse. La première est la répartition des fonctions avioniques associée à une contrainte d'ordonnancement hors-ligne sur les différents processeurs. La deuxième est la satisfaction des exigences de communication de bout-en-bout, dépendantes de l'allocation et l'ordonnancement des fonctions ainsi que des latences de communication sur les réseaux. La contribution majeure de cette thèse est la recherche d'un compromis entre la distribution des architectures IMA sur un plus grand nombre de processeurs et la satisfaction des exigences de communication de bout-en-bout. Nous répondons à cet enjeu de la manière suivante: - Nous formalisons dans un premier temps un modèle de partitions communicantes tenant en compte des contraintes d'allocation et d'ordonnancement des partitions d'une part et des contraintes de communication de bout-en-bout entre partitions d'autre part. - Nous présentons dans un deuxième temps une recherche exhaustive des architectures valides. Nous proposons l'allocation successive des fonctions avioniques en considérant au même niveau la problématique d'ordonnancement et la satisfaction des exigences de bout-en-bout avec des latences de communication figées. Cette méthode itérative permet de construire des allocations de partitions partiellement valides. La construction des ordonnancements dans chacun des processeurs est cependant une démarche coûteuse dans le cadre d'une recherche exhaustive. - Nous avons conçu dans un troisième temps une heuristique gloutonne pour réduire l'espace de recherche associé aux ordonnancements. Elle permet de répondre aux enjeux de distribution d'une architecture IMA dans un contexte hélicoptère. - Nous nous intéressons dans un quatrième temps à l'impact des latences de communication de bout-en-bout sur des architectures distribuées données. Nous proposons pour celles-ci les choix de réseaux basés sur les latences de communication admissibles entre les différentes fonctions avioniques. Les méthodes que nous proposons répondent au besoin industriel de l'étude de cas hélicoptère, ainsi qu'à celui de systèmes de plus grande taille. / Integrated Modular Architectures (IMA) is a major evolution of avionics systems. A spatial (predefined memory zones) and temporal (off-line scheduling) partitioning as well as communication resources reservation permit several systems not to interfere in this architecture. The determinism of systems is proved thanks to these static allocations: each system must respect end-to-end requirements in an asynchronous architecture. A worst-case study permits to assess the bounds of systems in order to verify that end-to-end requirements are satisfied in all the cases. IMA architectures physically centralize powerful computing resources in avionics bays in aircraft. These aren't feasible in helicopters due to size reasons: powerless processors, at least 80% used, set these architectures. In order to add new functionalities and equipment, the aim is to distribute processing power over a larger number of processors in the context of a globally asynchronous architecture. Two strong issues have been advanced throughout this thesis. The first one is the distribution of avionics functions with an off-line scheduling constraint on the different processors. The second one is the satisfaction of end-to-end requirements, depending on allocation and scheduling of functions as well as communication latencies over the networks. This thesis proposes a trade-off between the distribution of IMA architectures on a larger number of processors and the satisfaction of end-to-end communication requirements. We answer at this topic as follows: - First, we formalize a communicating partitions model based on the partitions allocation and scheduling constraints on the one hand and end-to-end communication constraints on the other hand. - Second, we present an exhaustive search of valid architectures. We introduce a successive allocation of avionics functions considering altogether the scheduling and the satisfaction of end-to-end constraints with fixed communication latencies. This iterative method allows the building of partially valid allocations schemes, but the scheduling search is expensive here. - Third, we create a greedy heuristic to reduce the scheduling search space. It permits to meet the challenges of the distribution of IMA architecture in a helicopter context. - Finally, we focus on the impact of end-to-end communication latencies on given distributed architectures. We define for them the networks based on eligible communication latencies between the different avionics functions. Our methods answer the industrial case study needs as well as bigger size systems needs.
14

Al-Juwaynī & Al-Ghazālī as theologians : with special reference to (Al-irshād) & (Al-iqtisād)

Bisar, M. A. R. January 1953 (has links)
The aim of this thesis is to expound and compare the theological aspect of the thought of al-Juwaynī and al-G̲h̲azālī; we shall seek to discover similarities and differences between them in their methods and in their opinions on identical problems. There are indeed several aspects from which the thought of these two men may be studied - the philosophical, the juristic, and the theological aspects. And their contribution to theology is an extremely important page in the history of the As̲h̲ʻarīyah school.
15

The Risk-Return Tradeoff in a Hedged, Client Driven Trading Portfolio / Relationen Mellan Risk och Avkastning i en Hedgead, Klientdriven Tradingportfölj

Bergvall, Anders January 2013 (has links)
In post-financial crisis times, new legislation in combination with banks’ changed risk aversion has to a great extent changed the proprietary trading to client driven trading, i.e. market making or client facilitation. This type of trading complicates the risk-return dynamics, as the goal is often to minimize risk and achieve profitable commission revenues. This thesis aims to disclose the risk-return tradeoff in a client driven trading environment. This is done by investigating the conditional relation between risk and realized return. As opposed from many studies which proxy the risk with beta or variance, I use a delta-gamma Value at Risk model as the risk proxy, which I also backtest. For the return proxy, I use three different measures; P&L, commission revenues and the sum of these two. A positive tradeoff exists if (i) the return is equally negatively dependent on the risk if the ex post return is negative, as it is positively dependent on the risk if the ex post return is positive and (ii) the average return is significantly positive. For three different client driven trading portfolios tested, I found a positive risk-return tradeoff in one portfolio, between the P&L plus commission revenues and the Value at Risk. However, since a symmetrical conditional relationship between risk and P&L plus commission revenues was found in all portfolios, and the average return was positive, the positive tradeoff would have existed if the average return would have been significantly positive. On the other hand, one could argue that the tradeoff exists, but is not significant. No relation between risk and commission revenues was found. A probable cause to this is the hedging strategies, which would be an interesting topic for further research. / I tiden efter finanskrisen har nya regelverk i kombination med bankers förändrade riskaptit till stor del förändrat den proprietära handeln till klientdriven handel, i.e. ”market making” eller förenklad handel för kund. Denna typ av handel komplicerar dynamiken mellan risk och avkastning, då målet ofta är att minimera risk och nå lönsamma kommissionsintäkter. Denna uppsats ämnar påvisa förhållandet mellan risk och avkastning i en klientdriven handelsmiljö. Detta görs genom att undersöka den betingade relationen mellan risk och realiserad avkastning. Till skillnad från andra studier som använder beta eller varians som riskmått, använder jag en delta-gamma Value at Risk-modell som jag också backtestar. Som avkastningsmått, använder jag tre olika mått; P&L, kommissionsintäkter samt summan av dessa två. En positiv belöning för att bära risk existerar om (i) avkastningen är lika negativt beroende av risken om den realiserade avkastningen är negativ, som den är positivt beroende av risken om den realiserade avkastningen är positiv och (ii) medelvärdet på avkastningen är signifikant positiv. För tre olika klientdrivna portföljer som testats, hittades en positiv belöning för att bära risk endast i en portfölj, mellan P&L plus kommissionsintäkter och Value at Risk. Emellertid, eftersom en symmetrisk systematisk betingad relation mellan risk och P&L plus kommissionsintäkter hittades i alla portföljer, och medelavkastningen var positiv, skulle den positiva belöningen ha funnits om medelavkastningen varit signifikant positiv. Å andra sidan skulle jag kunna hävda att den positiva belöningen finns, men inte är signifikant. Ingen relation mellan risk och kommissionsintäkter hittades. En trolig orsak till detta är hedgnings-strategierna, vilket vore ett intressant ämne för fortsatt forskning.
16

iCOMB: estudo e reprojeto participativo para redefinição de um sistema para ensino-aprendizagem de combinatória / iComb: study and participative design to redefine a system to teach and learn counting techniques

Silva, Márcia Roberta dos Santos Pires da 13 November 2015 (has links)
Os atuais avanços na área das Tecnologias da Informação e da Comunicação (TIC) estão mudando a Educação, com a disponibilização de sistemas educativos para apoiar as atividades no processo de ensino e de aprendizagem. Embora o tópico de combinatória seja relevante para o ensino médio e para os cursos de Ciências Exatas, este tópico tem sido desconsiderado nos avanços da Informática na Educação, principalmente ao se considerar o uso de ambientes de aprendizagem via Web. Atualmente, o iComb é, no melhor de nosso conhecimento, o único sistema Web integrável a tais ambientes. Ele é um Módulo de Aprendizagem Interativa (iMA) integrável ao Sistema Gerenciador de Cursos (SGC) Moodle, por meio do plugin iTarefa. O iComb oferece atividades de autoria de exercícios, bem como, sua avaliação automática. No entanto, considerando sua usabilidade, foram detectados alguns problemas na interface. O foco deste trabalho está relacionado ao reprojeto do sistema iComb e seu impacto na aprendizagem de combinatória. Para a reconstrução do iComb adotou-se o método de design de interação, buscando-se a participação efetiva de usuários finais do sistema, em todas as atividades desse processo, com (i) sessões de teste de usabilidade utilizando a versão Java do iComb para identificar problemas e guiar o redesenho do sistema, e (ii) prototipagem e avaliação da interface do sistema redesenhado. Esse processo permitiu implementar uma nova versão do iComb utilizando tecnologias associadas ao HTML5, que será brevemente disponibilizado como software livre. / Current advances in Information and Communication Technologies (ICT) are changing Education with delivering software to support learning/teaching activities. Although being relevant for Science, Technology, Engineering, and Mathematics (STEM) courses, Combinatorial Analysis is almost disregarded in these advances, mostly if we consider their integration with earning Management Systems. Currently, iComb is, at the best of our knowledge, the only system with such a possibility. It is an interactive Learning Module (iLM) that can be integrated to Moodle, through the iAssign plugin. iComb provides authoring activities as well as their automatic assessment. Nevertheless, considering the system usability, several interaction problems were detected during sessions with teachers and students. In this work it is described the process of redesigning the iComb system by adopting Interactive Design, to conduct controlled sessions of system use for (i) identifying usability issues for guiding the system redesign; and (ii) prototyping and evaluate the redesigned system interface, with end-users. This process allowed to implement new version of iComb using HTML5 related technologies that will be sooner available as free software, in order to reach a larger audience. Preliminary results on the interface evaluation indicate that both students and teachers felt more comfortable using the new interface of iComb and found it easier to execute common tasks.
17

iRepositório: repositório interativo de conteúdos digitais para cursos baseados na Internet / iRepository: Interactive Repository of Digital Contents for Internet based courses.

Nascimento, Mauricio Garcia Franco do 21 May 2014 (has links)
A crescente demanda por cursos baseados na World Wide Web (Web) tem imposto uma série de desafios para a área da Tecnologia da Informação e da Comunicação (TIC), em particular quando se considera a Educação apoiada pela Web. Uma das necessidades emergentes da Educação via Web está relacionada com o uso de Objetos de Aprendizagem (OA) dentro de Sistemas Gerenciadores de Curso (SGC). Além de considerar a produção de OA com \"qualidade\", deve-se providenciar seu armazenamento e disseminação de modo eficaz. Entretanto, algumas dificuldades tem sido reportadas por professores envolvidos com cursos pela Web, tais como: o \"custo elevado\" para a autoria do OA; a falta de ferramentas para o compartilhamento desses materiais; e experiências práticas negativas no reúso desses conteúdos em um SGC. Uma primeira proposta para mitigar esses problemas tem sido o desenvolvimento de ferramentas de Repositório de Objetos de Aprendizagem (ROA), visando principalmente facilitar a disseminação dos OA. Apesar do progresso já alcançado, ainda existem várias barreiras para a sua adoção pelos professores, como falta de integração simples entre o SGC e o ROA. Em geral as integrações atuais mostram-se difíceis para um usuário típico. Neste cenário, o objetivo deste projeto é apresentar um ROA inovador, o Repositório Interativo de Conteúdo Digital - iRepositório, cujo modelo prevê uma integração simplificada com um particular SGC e ainda oferece vários recursos para melhorar os processos de ensino e de aprendizagem, como o registro da eficácia educacional do OA. Como contribuição prática os fundamentos do iRepositório foram implementados para um SGC específico, o Moodle. Além de compartilhar OA entre cursos e usuários, ele provê recursos a outro componente do Moodle, o Tarefa Interativa - iTarefa, para armazenamento, classificação e busca de OA ou ainda facilidades para a manipulação dos Módulos de Aprendizagem Interativa (iMA). / The increasing demand for World Wide Web (Web) based courses has imposed some challenges in Information and Communications Technology (ICT) field, in particular when considering the education supported by the Web. One of the emerging needs of education supported by the Web is related to the Learning Objects (LO) usage inside Learning Management Systems (LMS). Besides production of \"good quality\" LO, it must be provided efficient methods concerning their storage and dissemination. However, some difficulties have been reported by teachers of Web based courses: \"expensive costs\" for LO authoring; lack of tools for sharing these materials; and negative practical experiences for reusing them in an LMS. Some proposals to mitigate these problems have been the development of Learning Object Repository (LOR) tools, mainly in order to facilitate the dissemination of LO. Despite the progress already achieved, there are still several barriers for their adoption by teachers such as lack of easy integration between LMS environment and LOR. In general, current integrations are not simple for typical users. In this context, the target of this project is to presents an innovative LOR, the Interactive Repository of Digital Contents - iRepository. Its model provides seamless integration with a particular LMS and offers several resources to help teaching and learning processes, such as registry of LO educational effectiveness. As a practical contribution, the fundamentals of iRepository model were implemented for an specific LMS, the Moodle system. Besides promoting LO sharing among courses and users, it provides resources to other Moodle component, the Interactive Assignment - iAssign, for storage, classification e searching of LO, or even ease management of Interactive Learning Module (iLM).
18

Automating Component-Based System Assembly

Subramanian, Gayatri 23 May 2006 (has links)
Owing to advancements in component re-use technology, component-based software development (CBSD) has come a long way in developing complex commercial software systems while reducing software development time and cost. However, assembling distributed resource-constrained and safety-critical systems using current assembly techniques is a challenge. Within complex systems when there are numerous ways to assemble the components unless the software architecture clearly defines how the components should be composed, determining the correct assembly that satisfies the system assembly constraints is difficult. Component technologies like CORBA and .NET do a very good job of integrating components, but they do not automate component assembly; it is the system developer's responsibility to ensure thatthe components are assembled correctly. In this thesis, we first define a component-based system assembly (CBSA) technique called "Constrained Component Assembly Technique" (CCAT), which is useful when the system has complex assembly constraints and the system architecture specifies component composition as assembly constraints. The technique poses the question: Does there exist a way of assembling the components that satisfies all the connection, performance, reliability, and safety constraints of the system, while optimizing the objective constraint? To implement CCAT, we present a powerful framework called "CoBaSA". The CoBaSA framework includes an expressive language for declaratively describing component functional and extra-functional properties, component interfaces, system-level and component-level connection, performance, reliability, safety, and optimization constraints. To perform CBSA, we first write a program (in the CoBaSA language) describing the CBSA specifications and constraints, and then an interpreter translates the CBSA program into a satisfiability and optimization problem. Solving the generated satisfiability and optimization problem is equivalent to answering the question posed by CCAT. If a satisfiable solution is found, we deduce that the system can be assembled without violating any constraints. Since CCAT and CoBaSA provide a mechanism for assembling systems that have complex assembly constraints, they can be utilized in several industries like the avionics industry. We demonstrate the merits of CoBaSA by assembling an actual avionic system that could be used on-board a Boeing aircraft. The empirical evaluation shows that our approach is promising and can scale to handle complex industrial problems.
19

Associação entre metabolismo do ferro e estresse oxidativo em pacientes com doeça de Parkinson

Medeiros, Márcio Schneider January 2014 (has links)
Introdução: A fisiopatologia da doença de Parkinson está associada a lesões por estresse oxidativo/nitrosativo. O ferro encontra-se acumulado na substância negra (SN) de pacientes com DP e está relacionado com esse dano através das espécies reagentes de oxigênio (EROs) e de nitrogênio (ERNs) na reação de Fenton. EROs e ERNs são produzidas normalmente em processos celulares e inflamatórios, e controladas por sistemas antioxidantes. Objetivo: Avaliar níveis periféricos de ferro em pacientes com DP para determinar se acúmulo na SN está relacionado com níveis elevados no sangue. Determinar biomarcadores periféricos confiáveis de estresse oxidativo/nitrosativo Métodos: Selecionados 40 pacientes com DP e 46 indivíduos controles para comparar níveis séricos de ferro, ferritina e transferrina, e de biomarcadores de estresse oxidativo/nitrosativo: superóxido dismutase (SOD), catalase, óxido nítrico (NOx), substâncias reativas ao ácido tiobarbitúrico (TBARS), tióis não-proteicos, “advanced oxidation protein products” (AOPP), “ferric reducing ability of plasma” (FRAP), NTPDases, ecto-5’-nucleotidase, adenosina deaminase (ADA), mieloperoxidase, albumina modificada pela isquemia (IMA) e vitamina C. Resultados: Níveis de ferro estavam diminuídos em pacientes com DP, enquanto ferritina e transferrina não mostraram diferença. Os biomarcadores de estresse oxidativo como TBARS, AOPP, NTPDases, IMA, mieloperoxidase, FRAP, vitamina C e tiois não-proteicos encontraram-se significativamente aumentados na DP. SOD, catalase, ecto-5’-nucleotidase não foram diferentes entre os grupos e os marcadores NOx e ADA foram significativamente aumentados nos controles. Nenhuma correlação foi encontrada entre os biomarcadores e dados sociodemográficos e de características da doença. Conclusão: Níveis plasmáticos de ferro encontram-se diminuídos em pacientes com DP comparados com controles saudáveis. Os biomarcadores TBARS, AOPP, NTPDases, IMA e mieloperoxidase mostraram-se confiáveis para lesão oxidativa, enquanto tióis não-proteicos, FRAP e vitamina C demonstram diminuição da capacidade antioxidante na DP. / Background: Parkinson’s disease (PD) pathophysiology is associated with oxidative/nitrosative stress damage. Iron accumulates in the substantia nigra (SN) of PD patients and is related to this damage along with oxygen and nitrogen reactive species (ROS, RNS) through Fenton reaction. ROS and RNS are normally produced in cell and inflammatory processes, controlled by antioxidant systems. Objective: To determine peripheral levels of iron, ferritin and transferrin in PD patients to evaluate whether iron accumulation in the SN could be related to serum levels. To determine reliable peripheral biomarkers of oxidative/nitrative stress. Methods: Forty PD patients and 46 controls were selected to compared serum levels of iron, ferritin, transferrin and oxidative/nitrative stress biomarkers: superoxide dismutase (SOD), catalase, nitric oxide (NOx), thiobarbituric acid reactive substances (TBARS), non-protein thiols, advanced oxidation protein products (AOPP), ferric reducing ability of plasma (FRAP), NTPDases, ecto-5’-nucleotidase, adenosine deaminase (ADA), myeloperoxidase, ischemic-modified albumin (IMA) and vitamin C. Results: Iron levels were decreased in patients with PD, while ferritin and transferrin were not different. Oxidative stress biomarkers, TBARS, AOPP, NTPDases, IMA, myeloperoxidase, FRAP, vitamin C and non-proteic thiols were significantly higher in PD. SOD, catalase, ecto-5’-nucleotidase were not different between the groups and biomarkers NOx and ADA were significantly increased in the controls. No correlation was found between biomarkers and sociodemographic and disease data. Conclusion: Plasmatic levels of iron are decreased in patients with PD compared to healthy controls. Biomarkers TBARS, AOPP, NTPDases, IMA and myeloperoxidase presented as reliable to measure oxidative/nitrative damage, while non-proteic thiols, FRAP and vitamin C show a decrease in the antioxidant capacity in PD.
20

Associação entre metabolismo do ferro e estresse oxidativo em pacientes com doeça de Parkinson

Medeiros, Márcio Schneider January 2014 (has links)
Introdução: A fisiopatologia da doença de Parkinson está associada a lesões por estresse oxidativo/nitrosativo. O ferro encontra-se acumulado na substância negra (SN) de pacientes com DP e está relacionado com esse dano através das espécies reagentes de oxigênio (EROs) e de nitrogênio (ERNs) na reação de Fenton. EROs e ERNs são produzidas normalmente em processos celulares e inflamatórios, e controladas por sistemas antioxidantes. Objetivo: Avaliar níveis periféricos de ferro em pacientes com DP para determinar se acúmulo na SN está relacionado com níveis elevados no sangue. Determinar biomarcadores periféricos confiáveis de estresse oxidativo/nitrosativo Métodos: Selecionados 40 pacientes com DP e 46 indivíduos controles para comparar níveis séricos de ferro, ferritina e transferrina, e de biomarcadores de estresse oxidativo/nitrosativo: superóxido dismutase (SOD), catalase, óxido nítrico (NOx), substâncias reativas ao ácido tiobarbitúrico (TBARS), tióis não-proteicos, “advanced oxidation protein products” (AOPP), “ferric reducing ability of plasma” (FRAP), NTPDases, ecto-5’-nucleotidase, adenosina deaminase (ADA), mieloperoxidase, albumina modificada pela isquemia (IMA) e vitamina C. Resultados: Níveis de ferro estavam diminuídos em pacientes com DP, enquanto ferritina e transferrina não mostraram diferença. Os biomarcadores de estresse oxidativo como TBARS, AOPP, NTPDases, IMA, mieloperoxidase, FRAP, vitamina C e tiois não-proteicos encontraram-se significativamente aumentados na DP. SOD, catalase, ecto-5’-nucleotidase não foram diferentes entre os grupos e os marcadores NOx e ADA foram significativamente aumentados nos controles. Nenhuma correlação foi encontrada entre os biomarcadores e dados sociodemográficos e de características da doença. Conclusão: Níveis plasmáticos de ferro encontram-se diminuídos em pacientes com DP comparados com controles saudáveis. Os biomarcadores TBARS, AOPP, NTPDases, IMA e mieloperoxidase mostraram-se confiáveis para lesão oxidativa, enquanto tióis não-proteicos, FRAP e vitamina C demonstram diminuição da capacidade antioxidante na DP. / Background: Parkinson’s disease (PD) pathophysiology is associated with oxidative/nitrosative stress damage. Iron accumulates in the substantia nigra (SN) of PD patients and is related to this damage along with oxygen and nitrogen reactive species (ROS, RNS) through Fenton reaction. ROS and RNS are normally produced in cell and inflammatory processes, controlled by antioxidant systems. Objective: To determine peripheral levels of iron, ferritin and transferrin in PD patients to evaluate whether iron accumulation in the SN could be related to serum levels. To determine reliable peripheral biomarkers of oxidative/nitrative stress. Methods: Forty PD patients and 46 controls were selected to compared serum levels of iron, ferritin, transferrin and oxidative/nitrative stress biomarkers: superoxide dismutase (SOD), catalase, nitric oxide (NOx), thiobarbituric acid reactive substances (TBARS), non-protein thiols, advanced oxidation protein products (AOPP), ferric reducing ability of plasma (FRAP), NTPDases, ecto-5’-nucleotidase, adenosine deaminase (ADA), myeloperoxidase, ischemic-modified albumin (IMA) and vitamin C. Results: Iron levels were decreased in patients with PD, while ferritin and transferrin were not different. Oxidative stress biomarkers, TBARS, AOPP, NTPDases, IMA, myeloperoxidase, FRAP, vitamin C and non-proteic thiols were significantly higher in PD. SOD, catalase, ecto-5’-nucleotidase were not different between the groups and biomarkers NOx and ADA were significantly increased in the controls. No correlation was found between biomarkers and sociodemographic and disease data. Conclusion: Plasmatic levels of iron are decreased in patients with PD compared to healthy controls. Biomarkers TBARS, AOPP, NTPDases, IMA and myeloperoxidase presented as reliable to measure oxidative/nitrative damage, while non-proteic thiols, FRAP and vitamin C show a decrease in the antioxidant capacity in PD.

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