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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

Rôle du Monoxyde d'Azote (NO) et des NO synthases dans la physiopathologie de la BPCO et de ses complications cardiovasculaires / The role of Nitric oxide (NO) and NO-synthases in COPD and its cardiovascular complications

Boyer, Laurent 18 July 2011 (has links)
Les mécanismes à l'origine de la Bronchopneumopathie Chronique Obstructive (BPCO) et de ses complications cardiovasculaires restent partiellement connus. Le NO est produit par les NO synthases en quantité importante dans le poumon des sujets emphysémateux, mais son rôle dans la maladie n'est pas connu. Une dysfonction endothéliale précoce liée à une diminution de la disponibilité en NO au niveau vasculaire a aussi été observée chez les patients BPCO. Dans un premier travail, nous avons montré que iNOS et eNOS étaient induites de manière diffuse dans le poumon de souris développant un emphysème après une instillation d'élastase. Le recours à des souris iNOS-/- et eNOS -/-, ainsi qu'à un inhibiteur pharmacologique d'iNOS (1400W) ont permis de montrer que l'induction d'iNOS dans le poumon était responsable d'une accumulation de protéines nitratées dans les pneumocytes de type 2 et d'une diminution de l'oxydation protéique. Cependant ni iNOS ni eNOS n'étaient nécessaires au développement de l'emphysème induit par l'élastase. Dans un deuxième travail, nous avons exploré l'effet de la polyglobulie, une complication de la BPCO hypoxique, sur la fonction endothéliale chez 15 patients polyglobuliques et 13 normoglobuliques atteints de BPCO de sévérité égale. La polyglobulie était associée de base à une viscosité sanguine plus élevée et un diamètre artérielbrachial plus important mais avec des forces de cisaillement calculées similaires. L'étude de la vasodilatation en réponse à l'hyperhémie et celle du flux sanguin de l'avant bras mesuré par plethysmographie d'occlusion veineuse en réponse à une perfusion d'acétylcholine (ACh), et de N-monomethyl-L-arginine (L-NMMA) ont permis de montrer que les artères systémiques despatients polyglobuliques ajustent leur diamètre aux forces de cisaillement aigues et chroniques de manière adaptée grâce à une libération adaptée de NO. De plus, nos résultats suggèrent que la polyglobulie modérée n'a pas d'effet délétère sur la fonctionvasculaire chez les patients BPCO. / The mechanisms that lead to COPD and cause its cardiovascular complications are partially known. NO is produced at high levels by NO-synthases in the human lung with emphysema, but its role in this disease is not clear. Interestingly, COPD patients have an endothelial dysfunction linked to the decrease of NO levels in peripheral blood vessels. In a first study, we demonstrated that iNOS and eNOS were diffusely upregulated in the lung of mice with emphysema after elastase instillation. By using iNOS-/- and eNOS -/- mice and a drug-based inhibitor of iNOS (1400W), we demonstrated that the induction of iNOS in the lung was responsible of an increase of protein nitration in alveolar type 2 cells and of an alleviated oxidation of proteins. However, neither iNOS nor eNOS were required for the development of elastase-induced inflammation and emphysema. In a second study, we evaluated the effectsof polycythemia, a common complication of hypoxic lung diseases, on the endothelial function in 15 polycythemic and 13 normocythemic patients with a COPD of equal severity. Polycythemia was associated with higher blood viscosity and a larger diameter of the brachial artery but with a similar calculated wall shear stress (WSS). We studied the flow-mediated brachial arteryvasodilation and the forearm blood-flow responses to endothelium- and non-endothelium-dependent N-monomethyl-L-arginine (LNMMA) infusion by plethysmography. We demonstrated that systemic arteries in polycythemic patients adjust appropriately to chronic or acute WSS elevations by an appropriate basal and stimulated NO release. Overall, our results suggest that moderate polycythemia has no adverse effect on vascular function in COPD.
12

Hétérogénéité génétique de la polyglobulie

Al-Sheikh, Maha 17 December 2008 (has links)
La polyglobulie (PG) a un arrière plan clinique et physiopathologique varié, et dont la connaissance a beaucoup évolué depuis 5 ans. Elle a pour caractéristique nécessaire et commune une augmentation du volume globulaire total qui peut résulter de mécanismes moléculaires différents. L'érythrocytose est une forme de la PG ou` seule la lignée érythroïde semble être augmentée. Dans ce contexte, nous nous sommes intéressés à la mutation JAK2 (Val617Phe) et aux gênes EPOR, VHL, PHD2 chez des patients présentant une érythrocytose d'origine inconnue (98 familles). Nous avons trouvé 3 nouvelles mutations délétionnelles et d'autres mutations faux-sens et silencieuses sur EPOR. Les cellules FDCP-1 et 32D transfectées, qui expriment les récepteurs tronqués ont montré une hypersensibilité à l'EPO à concentration basse. Les analyses EPO-dose-réponse pour une mutation faux-sens étaient semblables à celles du type sauvage. La mutation JAK2(Val617Phe) était présente avec une faible fréquence dans la série de patients étudiés. La recherche des mutations dans le gêne PHD2 nous a permis de trouver 3 nouvelles mutations frame-shift et non-sens, les seules connues à ce jour: Elles entraînent la perte d'une partie ou de l'ensemble du site catalytique de PHD2 dans l'hypothèse où elles seraient synthétisées. Ainsi, ces mutations et les deux autres mutations faux-sens décrites démontrent l'importance de PHD2 dans la régulation de la voie de HIF-a, et qu'une perturbation de cette régulation pourrait conduire à une PG. La majorité des patients reste sans défaut moléculaire identifié, et des recherches complémentaires sont nécessaires. Nous avons également étudié deux Hbs augmentant l'affinité pour l'oxygène: les Hbs Nantes et La Coruña. Enfin, nous avons cherché des mutations dans les 3 exons de DPGM chez 4 patients avec un taux de 2,3-DPG bas. Une seule mutation a été trouvée dans la région 5`, dans l'exon 1 non traduit, elle nécessite des études complémentaires. / Polycythemia has a varied clinical and physiopathological background, of which our knowledge has greatly evaluated since 5 years. It is characterised by augmentation of the red cell mass which can be resulted from different molecular mechanisms. Erythrocytosis is a form of polycythemia where only the erythrocytes are augmented. In this context, we looked for the mutation JAK2 (Val617Phe), and other mutations in the genes of EPOR, VHL, PHD2 in a series of patients with erythrocytosis of unknown origin (98 families). We found 3 new frame-shift mutations and other missense and silent mutations in the EPOR. Transfected FDCP-1 and 32D cell lines expressing a truncated EpoR showed increased sensitivity at low concentration of Epo. However, in the case of a missense EPOR mutation, the Epo-dose response assays were similar to that of the wild type. The mutation JAK2 (Val617Phe) was found at a low frequency in the studied patients. Looking for mutations in the PHD2 gene allowed us to find 3 new frame-shift and nonsense mutations, the only reported to date. The encoded PHD2, if synthesized, would lose its active site or a part of it. These mutations with the other two missense mutations reported provide the evidence of the importance of PHD2 in the regulation of HIF-a pathway, and that disturbing the oxygen-sensing pathway might be a cause of polycythemia. The molecular basis of polycythemia in the majority of patients is still to be identified, and complementary studies are necessary. We studied then two examples of Hbs with a high oxygen affinity: Hb Nantes et La Coruña. Finally, we looked for mutations in the 3 exons of DPGM in a series of 4 patients. One mutation in exon 1 in the 5`region was found, and needs further studies.
13

Impacto da análise molecular da mutação JAK2V617F no diagnóstico de neoplasias mieloproliferativas crônicas de acordo com os critérios da OMS 2016

Pedrazzani, Fabiane Spagnol January 2016 (has links)
As neoplasias mieloproliferativas (NMPs) são um grupo de doenças derivadas de uma transformação clonal de célula tronco hematopoiéticas no qual a linhagem celular mielóide é predominantemente expandida no sangue periférico. As NMPs Philadelphia-negativas incluem policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) que compartilham muitas características hematológicas, clínicas e evolutivas. A mutação da JAK2 (JAK2V617F) está presente em cerca de 95% dos pacientes com PV, entre 50 a 70% com TE e 40 a 50% com MFP. No entanto, os testes moleculares para diagnóstico são muitas vezes um desafio devido ao alto custo e a disponibilidade de equipamentos especializados. Objetivo: Verificar o impacto do teste molecular da mutação JAK2V617F para o diagnóstico de NMPs nos pacientes atendidos no Hospital de Clínicas de Porto Alegre. Métodos: Foram avaliados 87 pacientes com suspeita de NMPs. As amostras de sangue periférico foram analisadas para a mutação JAK2V617F pelo método genético molecular de PCR alelo-específico e os resultados correlacionados com os dados clínico-laboratoriais. Para estabelecimento do diagnóstico, foram utilizados os critérios da Organização Mundial da Saúde (OMS) de 2016. Resultados: Dos 87 pacientes avaliados, 27,6% foram diagnosticados como PV, 39,1% como TE, 4,6% como MFP e 28,7% não contemplavam os critérios para o diagnóstico NMPs. A comparação da utilização do teste da mutação JAK2V617F mostrou que, apenas 41,7% dos pacientes com PV sem utilizar o teste, teriam sido diagnosticados comparados a 91,7% utilizando este teste como um dos critérios no diagnóstico final (p = 0,004). Na TE e na MFP, este critério não foi estatisticamente significativo. Conclusão: O teste molecular para a mutação de JAK2V617F no nosso hospital teve um impacto significativo no diagnóstico dos pacientes com PV, mostrando ser uma ferramenta importante para o diagnóstico final desta NMP. / Myeloproliferative neoplasms (MPNs) are a group of disorders derived from a clonal transformation of stem cell on which myeloid cell lineage is predominantly expanded in the peripheral blood. Philadelphia-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) which share many hematological, clinical, and evolutionary characteristics. The JAK2 mutation (JAK2V617F) is present in about 95% of patients with PV, between 50 to 70% with ET and 40 to 50% PMF. However, the molecular diagnostic tests are often a challenge due to the high cost and the availability of specialized equipment. Objective: To verify the impact of molecular testing of the JAK2V617F mutation for the diagnosis of MPNs in patients attended at Hospital de Clinics, Porto Alegre. Methods: A total of 97 patients were evaluated with suspected of MPNs. The peripheral blood samples were analyzed for the JAK2V617F mutation by the molecular genetic allelespecific PCR method and the results correlated with the clinical-laboratory data. To establish the diagnosis, the 2016 World Health Organization (WHO) criteria were used. Results: Of the 87 patients evaluated, 27.6% were diagnosed as PV, 39.1% as ET, 4.6% as PMF and 28.7% did not meet criteria for MPNs diagnosis. Comparison of the use of the JAK2V617F test showed that only 41.7% of patients with PV without the mutation test were diagnosed compared to 91.7% using this test as one of the criteria for the final diagnosis (p = 0.004). In the ET and the PMF, this criterion was not statistically significant. Conclusion: The molecular test for the JAK2V617F mutation in our hospital had a significant impact in the diagnosis of patients with PV, showing to be an important tool for the final diagnosis of this MPN.
14

Impacto da análise molecular da mutação JAK2V617F no diagnóstico de neoplasias mieloproliferativas crônicas de acordo com os critérios da OMS 2016

Pedrazzani, Fabiane Spagnol January 2016 (has links)
As neoplasias mieloproliferativas (NMPs) são um grupo de doenças derivadas de uma transformação clonal de célula tronco hematopoiéticas no qual a linhagem celular mielóide é predominantemente expandida no sangue periférico. As NMPs Philadelphia-negativas incluem policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) que compartilham muitas características hematológicas, clínicas e evolutivas. A mutação da JAK2 (JAK2V617F) está presente em cerca de 95% dos pacientes com PV, entre 50 a 70% com TE e 40 a 50% com MFP. No entanto, os testes moleculares para diagnóstico são muitas vezes um desafio devido ao alto custo e a disponibilidade de equipamentos especializados. Objetivo: Verificar o impacto do teste molecular da mutação JAK2V617F para o diagnóstico de NMPs nos pacientes atendidos no Hospital de Clínicas de Porto Alegre. Métodos: Foram avaliados 87 pacientes com suspeita de NMPs. As amostras de sangue periférico foram analisadas para a mutação JAK2V617F pelo método genético molecular de PCR alelo-específico e os resultados correlacionados com os dados clínico-laboratoriais. Para estabelecimento do diagnóstico, foram utilizados os critérios da Organização Mundial da Saúde (OMS) de 2016. Resultados: Dos 87 pacientes avaliados, 27,6% foram diagnosticados como PV, 39,1% como TE, 4,6% como MFP e 28,7% não contemplavam os critérios para o diagnóstico NMPs. A comparação da utilização do teste da mutação JAK2V617F mostrou que, apenas 41,7% dos pacientes com PV sem utilizar o teste, teriam sido diagnosticados comparados a 91,7% utilizando este teste como um dos critérios no diagnóstico final (p = 0,004). Na TE e na MFP, este critério não foi estatisticamente significativo. Conclusão: O teste molecular para a mutação de JAK2V617F no nosso hospital teve um impacto significativo no diagnóstico dos pacientes com PV, mostrando ser uma ferramenta importante para o diagnóstico final desta NMP. / Myeloproliferative neoplasms (MPNs) are a group of disorders derived from a clonal transformation of stem cell on which myeloid cell lineage is predominantly expanded in the peripheral blood. Philadelphia-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) which share many hematological, clinical, and evolutionary characteristics. The JAK2 mutation (JAK2V617F) is present in about 95% of patients with PV, between 50 to 70% with ET and 40 to 50% PMF. However, the molecular diagnostic tests are often a challenge due to the high cost and the availability of specialized equipment. Objective: To verify the impact of molecular testing of the JAK2V617F mutation for the diagnosis of MPNs in patients attended at Hospital de Clinics, Porto Alegre. Methods: A total of 97 patients were evaluated with suspected of MPNs. The peripheral blood samples were analyzed for the JAK2V617F mutation by the molecular genetic allelespecific PCR method and the results correlated with the clinical-laboratory data. To establish the diagnosis, the 2016 World Health Organization (WHO) criteria were used. Results: Of the 87 patients evaluated, 27.6% were diagnosed as PV, 39.1% as ET, 4.6% as PMF and 28.7% did not meet criteria for MPNs diagnosis. Comparison of the use of the JAK2V617F test showed that only 41.7% of patients with PV without the mutation test were diagnosed compared to 91.7% using this test as one of the criteria for the final diagnosis (p = 0.004). In the ET and the PMF, this criterion was not statistically significant. Conclusion: The molecular test for the JAK2V617F mutation in our hospital had a significant impact in the diagnosis of patients with PV, showing to be an important tool for the final diagnosis of this MPN.
15

Impacto da análise molecular da mutação JAK2V617F no diagnóstico de neoplasias mieloproliferativas crônicas de acordo com os critérios da OMS 2016

Pedrazzani, Fabiane Spagnol January 2016 (has links)
As neoplasias mieloproliferativas (NMPs) são um grupo de doenças derivadas de uma transformação clonal de célula tronco hematopoiéticas no qual a linhagem celular mielóide é predominantemente expandida no sangue periférico. As NMPs Philadelphia-negativas incluem policitemia vera (PV), trombocitemia essencial (TE) e mielofibrose primária (MFP) que compartilham muitas características hematológicas, clínicas e evolutivas. A mutação da JAK2 (JAK2V617F) está presente em cerca de 95% dos pacientes com PV, entre 50 a 70% com TE e 40 a 50% com MFP. No entanto, os testes moleculares para diagnóstico são muitas vezes um desafio devido ao alto custo e a disponibilidade de equipamentos especializados. Objetivo: Verificar o impacto do teste molecular da mutação JAK2V617F para o diagnóstico de NMPs nos pacientes atendidos no Hospital de Clínicas de Porto Alegre. Métodos: Foram avaliados 87 pacientes com suspeita de NMPs. As amostras de sangue periférico foram analisadas para a mutação JAK2V617F pelo método genético molecular de PCR alelo-específico e os resultados correlacionados com os dados clínico-laboratoriais. Para estabelecimento do diagnóstico, foram utilizados os critérios da Organização Mundial da Saúde (OMS) de 2016. Resultados: Dos 87 pacientes avaliados, 27,6% foram diagnosticados como PV, 39,1% como TE, 4,6% como MFP e 28,7% não contemplavam os critérios para o diagnóstico NMPs. A comparação da utilização do teste da mutação JAK2V617F mostrou que, apenas 41,7% dos pacientes com PV sem utilizar o teste, teriam sido diagnosticados comparados a 91,7% utilizando este teste como um dos critérios no diagnóstico final (p = 0,004). Na TE e na MFP, este critério não foi estatisticamente significativo. Conclusão: O teste molecular para a mutação de JAK2V617F no nosso hospital teve um impacto significativo no diagnóstico dos pacientes com PV, mostrando ser uma ferramenta importante para o diagnóstico final desta NMP. / Myeloproliferative neoplasms (MPNs) are a group of disorders derived from a clonal transformation of stem cell on which myeloid cell lineage is predominantly expanded in the peripheral blood. Philadelphia-negative MPNs include polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF) which share many hematological, clinical, and evolutionary characteristics. The JAK2 mutation (JAK2V617F) is present in about 95% of patients with PV, between 50 to 70% with ET and 40 to 50% PMF. However, the molecular diagnostic tests are often a challenge due to the high cost and the availability of specialized equipment. Objective: To verify the impact of molecular testing of the JAK2V617F mutation for the diagnosis of MPNs in patients attended at Hospital de Clinics, Porto Alegre. Methods: A total of 97 patients were evaluated with suspected of MPNs. The peripheral blood samples were analyzed for the JAK2V617F mutation by the molecular genetic allelespecific PCR method and the results correlated with the clinical-laboratory data. To establish the diagnosis, the 2016 World Health Organization (WHO) criteria were used. Results: Of the 87 patients evaluated, 27.6% were diagnosed as PV, 39.1% as ET, 4.6% as PMF and 28.7% did not meet criteria for MPNs diagnosis. Comparison of the use of the JAK2V617F test showed that only 41.7% of patients with PV without the mutation test were diagnosed compared to 91.7% using this test as one of the criteria for the final diagnosis (p = 0.004). In the ET and the PMF, this criterion was not statistically significant. Conclusion: The molecular test for the JAK2V617F mutation in our hospital had a significant impact in the diagnosis of patients with PV, showing to be an important tool for the final diagnosis of this MPN.
16

Estudo funcional de variantes estruturais da hemoglobina humana / Functional studies of structural variants of human hemoglobin

Jorge, Susan Elisabeth Domingues Costa, 1983- 14 August 2018 (has links)
Orientadores: Maria de Fatima Sonati, Munir Salomão Skaf / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T12:16:23Z (GMT). No. of bitstreams: 1 Jorge_SusanElisabethDominguesCosta_M.pdf: 12500595 bytes, checksum: 271d153e901aa04d248746dbcf6d90c6 (MD5) Previous issue date: 2009 / Resumo: A hemoglobina (Hb), pigmento respiratório de todos os organismos vertebrados, encontra-se em elevadas concentrações nas hemácias e é responsável pelo transporte de O2 dos pulmões para os tecidos. A Hemoglobina humana constitui-se de dois pares de cadeias polipeptídicas (globinas), cada qual envolvendo um grupo prostético heme, que se liga reversivelmente ao O2. Mais de 1000 variantes estruturais da Hb humana já foram descritas, parte delas relacionada a manifestações clinicas importantes. Algumas variantes apresentam alteração funcional, que se traduz em afinidade modificada pelo O2. Quando elevada, há uma produção compensatoriamente maior de hemácias, levando a policitemia; quando diminuída, resulta em cianose. O Laboratório de Hemoglobinopatias do Departamento de Patologia Clinica da FCM/UNICAMP e um dos laboratórios de referencia no pais, tendo identificado, ate o momento, 12 hemoglobinas novas e 51 variantes raras. Destas, as variantes novas Hb Hb Boa Esperanca (?16 Lys?Thr), Hb Itapira (?30 Glu?Val), Hb Bom Jesus da Lapa (?30 Glu?Ala), Hb Olinda [ß22 (b4) -25 (b7)], Hb Caruaru (ß 122 Phe?Ser) e Hb S-Sao Paulo (ß6 Glu?Val ; ß65 Lys?Glu) foram aqui caracterizadas funcionalmente, assim como as variantes raras Hb Iwata (a87 His??Arg), Hb Sunshine Seth (?94 Asp?His), Hb Deer Lodge (ß2 His?Arg), Hb Deer Lodge (ß2 His??Arg) + Hb S (ß6 Glu??Val), Hb G-Siriraj (ß7 Glu??Lys), Hb G-Siriraj (ß7 Glu??Lys) e Hb C (ß6 Glu??Lys) em associacao, Hb M-Saskatoon (ß63 His??Tyr), Hb Redondo (ß92 His? Asn), Hb Koln (ß98 Val??Met), Hb Coimbra (ß99 Asp??Glu) e Hb Dhonburi (ß126 Val?Gli)+ Btal. O metodo analitico empregado foi descrito por Rossi-Fanelli & Antonini (1958), e analisa espectrofotometricamente o comportamento da Hb frente a conhecidas pressões parciais de oxigênio (pO2), possibilitando a medida de afinidade (p50), da constante de Hill (n), que verifica o fenômeno de cooperatividade entre as cadeias globinicas para ligação do O2, o efeito Bohr (que indica facilidade na ligação Hb-O2 conforme e elevado o pH do meio), bem como a interação com o Inositol Hexafosfato (IHP), um fosfato polianion que dificulta a ligação entre a Hb e o O2. A exceção das Hbs Itapira e Bom Jesus da Lapa, em concentrações reduzidas nos hemolisados, todas as demais apresentam afinidade alterada pelo oxigênio. Como complementação ao estudo funcional, as Hbs Caruaru e São Paulo também foram submetidas a analise por dinâmica molecular, através dos programas VMD (Visual Molecular Dynamics), com dados inseridos nos softwares CHARMM (Chemistry at Harvard Molecular Mechanics) e NAMD (Nanoscale Molecular Dynamics). As demais variantes tiveram sua analise estrutural individualizada feita através da visualização de estruturas nativas depositadas no Protein Data Bank, para melhor compreensão da relação entre o aminoácido substituído e a função protéica alterada. Deste modo, foi possível estabelecer correlações entre a estrutura e a função e inferir sobre as manifestações clinicas resultantes da presença destas heme proteínas anômalas, ilustrando-se assim a importância desses estudos para a completa caracterização das variantes. / Abstract: The human hemoglobin (Hb) is the respiratory pigment of human organisms, found in high concentrations in the erythrocytes and is responsible for transporting O2 from the lungs to the peripheral tissues. This molecule is composed by two pairs of polypeptide chains (globin), each one involving a prosthetic group heme, which bind reversibly to the O2. More than 1000 structural variants had been described already; part of them related to important clinical manifestations. Some variants present functional alteration, with modified affinity for the O2. When it is increased, it has a higher compensatory production of the erythrocytes, causing policitemia; when decreased, it results on cyanosis. The Laboratory of Hemoglobinopaties of the Department of Clinical Pathology of the FCM/UNICAMP is one of the references laboratories in the country, and identified, until this moment, 12 new hemoglobins and 51 rare variants. The new variants Hb Hb Boa Esperanca (?16 Lys?Thr), Hb Itapira (?30 Glu?Val), Hb Bom Jesus da Lapa (?30 Glu?Ala), Hb Olinda [ß22 (b4) -25 (b7)], Hb Caruaru (ß 122 Phe?Ser) e Hb S-Sao Paulo (ß6 Glu?Val ; ß65 Lys?Glu) were, in the present study, functionally characterized, as well as the rare variants Hb Iwata (a87 His??Arg), Hb Sunshine Seth (?94 Asp?His), Hb Deer Lodge (ß2 His?Arg), Hb Deer Lodge (ß2 His??Arg) + Hb S (ß6 Glu??Val), Hb G-Siriraj (ß7 Glu??Lys), Hb G-Siriraj (ß7 Glu??Lys) e Hb C (ß6 Glu??Lys) em associacao, Hb M-Saskatoon (ß63 His??Tyr), Hb Redondo (ß92 His? Asn), Hb Koln (ß98 Val??Met), Hb Coimbra (ß99 Asp??Glu) e Hb Dhonburi (ß126 Val?Gli)+ Btal. The analytical method used was described for Rossi-Fanelli & Antonini (1958), which analyses, by spectrophotometer, the behavior of the Hb against known partial pressures of oxygen (pO2), making possible the measure of affinity (p50), the constant of Hill (n), that verifies the cooperativity, the Bohr effect (that it indicates the relation between Hb-O2 binding according to the pH), as well as the interaction with Inositol Hexaphosphoric acid (IHP), that difficult linkage between the Hb and the O2. Except from Hb Itapira and Hb Bom Jesus of the Lapa, in reduced concentrations at the total hemolysate, all the others presented modified affinity to the oxygen. As a complement of the functional study, the Hb Caruaru and Hb S-Sao Paulo were also submitted to previous molecular dynamics simulation. All the other variants were structurally analyzed by the study of the native structure deposited at the Protein Data Bank, to understand better the relation between the substituted residue and the modified one at the protein function. Therefore, it was possible to establish correlations between the structure and the function and to infer on the clinical manifestations because of the presence of these anomalous proteins, illustrating the importance of these studies for the complete characterization of the variants. / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas
17

Right Atrial Myxoma With Extracardiac Manifestations

McCoskey, Eugene H., Mehta, Jayant B., Krishnan, K., Roy, Thomas M. 01 January 2000 (has links)
Right atrial myxoma is a rare intracardiac tumor that is often difficult to diagnose. Pulmonary embolism from tumor fragments originating from the tumor mass is a potentially fatal complication. Early diagnosis of cardiac myxoma is important since surgical treatment leads to resolution with low rates of recurrence and good long-term survival. The presence of a cardiac myxoma can be heralded by nonspecific constitutional symptoms as well as by disturbances in the clotting mechanism.
18

Expressão de microRNAs em leucócitos e células CD34+ em Policitemia Vera / microRNA expression in leukocytes and CD34+ cells in Polycythemia Vera

Nunes, Natália de Souza 25 January 2012 (has links)
A Neoplasia Mieloproliferativa Crônica (NMPC)- Politemia Vera é uma desordem clonal caracterizada pelo acúmulo de eritrócitos, leucócitos, plaquetas e progenitores normais na ausência de um estímulo definido. Apesar dos avanços no diagnóstico de PV e da descrição de mecanismos envolvidos no estabelecimento da doença sua patogênese permanece desconhecida entretanto, alterações no mecanismo regulador da apoptose parecem estar envolvidos em sua fisiopatologia. A compreensão acerca do funcionamento da maquinaria apoptótica e sua possível regulação por microRNAs em pacientes com Policitemia Vera parece revelar novos alvos para estudo e consequentemente transformar-se em novas terapias para a doença. Neste contexto os objetivos deste trabalho foram avaliar em leucócitos de sangue periférico e células CD34+ de medula óssea dos pacientes de PV: (1) a quantificação da expressão de microRNAs cujos alvos são RNAs associados a regulação da apoptose; (2) Correlação dos níveis de expressão dos miRNAs com os de RNAm das moléculas pró e antiapoptóticas da família Bcl-2 e dos receptores de morte; (3) Correlação dos níveis de expressão dos miRNAs com os seguintes dados clínico-laboratoriais dos pacientes: concentração de hemoglobina, hematócrito e percentagem da mutação JAK2. Os pacientes com Policitemia Vera apresentam aumento de expressão dos microRNAs 29c, 16, 21, 26a, 130b e let-7d e diminuição de miR15a e 34c em leucócitos de sangue periférico; Aumento de expressão dos miRs 29c, 16 e 21; diminuição na expressão de miR 130b e let-7d em células CD34+ ; alteração na expressão de genes pró e anti-apoptóticos em leucócitos de sangue periférico com aumento de a1, mcl-1 e diminuição de bcl-2, ciap-2, bax e fas-L,alteração na expressão de genes pró e anti-apoptóticos em células CD34+ com aumento de expressão de fas, bid, mcl-1, bcl-xl e c-flip; diminuição na expressão de bik. Observamos diminuição na expressão protéica de BCL-2 em pacientes quando comparado aos indivíduos controle.Notamos também a correlação entre a alteração na expressão de microRNAs e seus respectivos genes alvo e destes com parâmetros hematológicos analisados. Os linfócitos dos pacientes de PV apresentam maior resistência a apoptose do que os indivíduos controles quando induzidos por: Actinomicina, etoposídeo, citarabina e cicloheximida. Concluindo, os dados obtidos sugerem a participação dos microRNAs na regulação da maquinaria apoptótica e a participação desta desregulação na fisiopatologia da PV. Estes resultados contribuem para o melhor entendimento da fisiopatologia da PV e serão úteis futuramente para o desenho de novos alvos terapêuticos e descrição de marcadores de prognóstico. / Polycythaemia vera (PV) is a clonal disorder characterized by an accumulation of normal red and white cells, platelets, and their progenitors in absence of a definable stimulus. Despite the advances in PV diagnosis and the description of the mechanisms involved in disease establishment its pathogenesis remains unclear. The apoptosis deregulation might have a role in PV physiopathology. Fully understanding the basic apoptotic pathway and its potential regulation by microRNA in PV patients cells might unveil targets for manipulation, which may be translated into novel therapies for disease.The aims of this study were to avaluate in leukocytes and CD34+ cells: (1) The microRNA expression whose RNA target are associated with apoptosis regulation (2) Correlation between microRNA expression and the mRNA levels of anti and pro-apoptotic family Bcl-2 expression and death receptors; (3) Correlation between microRNA expression and the clinical data of patients: hemoglobin concentration, hematocrit and JAK2 percentage. Patientes with Polycythemia Vera shows increased expression of microRNAs 29c, 16, 21, 26a, 130b and let-7d and 34c and 15a decrease in peripheral leukocytes; incresead expression of miRs 29c, 16 and 21, decrease in miR130b and let-7d expression in CD34+ cells; deregulation in pro and anti-apoptotic gene expression in peripheral leukocytes with increase in a1, mcl-1 and decrease in bcl-2, ciap-2, bax and fas-L, deregulation in pro and anti-apoptotic gene expression in CD34+ cells with increased expression of fas, bid, mcl-1, bcl-xl and c-flip and decreased expression of bik. Decreased in proteic expression of BCL-2 in peripheral leukocytes of patients when compared to controls. Correlation between de deregulated expression of microRNA and their genes target and those with hematological parameters. Lymphocytes from PV patients shows higher resistance to apoptosis than controls when induced by: Actinomicin, etoposide, cytarabine and cycloheximide. In conclusion the data suggest the involvement of microRNA in apoptosis regulation and the involvement of apoptosis machinery in the PV pathophysiology. These results will contribute for a better understanding of PV pathophysiology and will be useful for the discover of future therapies.
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Rôle du Monoxyde d'Azote (NO) et des NO synthases dans la physiopathologie de la BPCO et de ses complications cardiovasculaires

Boyer, Laurent 18 July 2011 (has links) (PDF)
Les mécanismes à l'origine de la Bronchopneumopathie Chronique Obstructive (BPCO) et de ses complications cardiovasculaires restent partiellement connus. Le NO est produit par les NO synthases en quantité importante dans le poumon des sujets emphysémateux, mais son rôle dans la maladie n'est pas connu. Une dysfonction endothéliale précoce liée à une diminution de la disponibilité en NO au niveau vasculaire a aussi été observée chez les patients BPCO. Dans un premier travail, nous avons montré que iNOS et eNOS étaient induites de manière diffuse dans le poumon de souris développant un emphysème après une instillation d'élastase. Le recours à des souris iNOS-/- et eNOS -/-, ainsi qu'à un inhibiteur pharmacologique d'iNOS (1400W) ont permis de montrer que l'induction d'iNOS dans le poumon était responsable d'une accumulation de protéines nitratées dans les pneumocytes de type 2 et d'une diminution de l'oxydation protéique. Cependant ni iNOS ni eNOS n'étaient nécessaires au développement de l'emphysème induit par l'élastase. Dans un deuxième travail, nous avons exploré l'effet de la polyglobulie, une complication de la BPCO hypoxique, sur la fonction endothéliale chez 15 patients polyglobuliques et 13 normoglobuliques atteints de BPCO de sévérité égale. La polyglobulie était associée de base à une viscosité sanguine plus élevée et un diamètre artérielbrachial plus important mais avec des forces de cisaillement calculées similaires. L'étude de la vasodilatation en réponse à l'hyperhémie et celle du flux sanguin de l'avant bras mesuré par plethysmographie d'occlusion veineuse en réponse à une perfusion d'acétylcholine (ACh), et de N-monomethyl-L-arginine (L-NMMA) ont permis de montrer que les artères systémiques despatients polyglobuliques ajustent leur diamètre aux forces de cisaillement aigues et chroniques de manière adaptée grâce à une libération adaptée de NO. De plus, nos résultats suggèrent que la polyglobulie modérée n'a pas d'effet délétère sur la fonctionvasculaire chez les patients BPCO.
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Comorbidities Associated with Polycythemia Vera and Factors Influencing Cost and Mortality in Inpatient Hospital Settings

Pritchett, Lanae, Knutson, Jennifer, Skrepnek, Grant January 2011 (has links)
Class of 2011 Abstract / OBJECTIVES: To assess the role of patient, payer, clinical and disease-related factors in charges and mortality among adult inpatient cases of polycythemia vera in the United States from 2004 to 2008. METHODS: This retrospective cohort study utilized hospital discharge records from the Agency for Healthcare Research and Quality (AHRQ) Healthcare Cost and Utilization Project (HCUP) Nationwide Inpatient Sample (NIS) five consecutive years from 2004 to 2008. RESULTS: There were a total of 156,490 episodes of care involving polycythemia vera between 2004 and 2008. Average age upon admission was 65.94 years (±16.03), with 56% of cases being male (n=87,662). The mean length of stay was 5.14 days (±5.31) and inpatient mortality occurred in 3.1% of cases (n=4,927). The mean number of procedures performed was 1.43 (±2.08) and the mean number of diagnoses on record was 9.56 (±3.86). Charges for each episode of care averaged $32,620 (±42,801), summing to a national bill of $5.02 billion (2010 dollars) over the five-year time horizon. Higher charges were associated with longer length of stay, larger hospital bed size, urban hospital location, teaching status, increased number of diagnoses and procedures, private payer, Western U.S. region, and higher income bracket. Increased mortality was associated with increased age, increased number of diagnoses and procedures, self pay, payer other than Medicare, Medicaid, private or self, and the comorbidities of congestive heart failure, coagulopathy, and fluid/electrolyte disorders. CONCLUSION: Polycythemia vera is associated with considerable burden of illness.

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