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Enzymatic Regulation of Opioid Antinociception and ToleranceHull, Lynn 12 July 2009 (has links)
ENZYMATIC REGULATION OF OPIOID ANTINOCICEPTION AND TOLERANCE By Lynn C. Hull, Ph.D. A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at Virginia Commonwealth University. Virginia Commonwealth University, 2009 Director: William L. Dewey, Ph.D. Department of Pharmacology and Toxicology The involvement of kinases in opioid actions has long been established. The acute actions of opioids, through the Gi/Go G-proteins, cause the inhibition of adenylyl cyclase and therefore a decrease in protein kinase A (PKA) activation. Additionally, acute opioid administration may cause the G-protein to activate the phospholipase C (PLC)-mediated cascade leading to the activation of protein kinase C (PKC). The phosphorylation of the MOR which can lead to both desensitization by uncoupling of the G-protein coupled receptors (GPCRs) from the G-proteins and to internalization by recruitment of β-arrestins has long been identified as a key process in tolerance. Phosphorylation by PKA and PKC leads primarily to uncoupling of the receptor from the G-proteins. Phosphorylation of the receptor by G-protein coupled receptor kinase (GRK) leads to the recruitment of β-arrestins and internalization of the receptor. Many in vitro studies have come to the conclusion that GRK induced internalization plays a more central role in the tolerance to high efficacy opioids and a lesser role in low- and moderate-efficacy opioid tolerance. In fact it has been hypothesized that morphine, a moderate-efficacy opioid, causes no internalization at all, while the desensitization of the receptor via phosphorylation by PKA and PKC plays a more central role in low- and moderate-efficacy opioid tolerance. We sought to test these in vitro findings in an in vivo model of opioid tolerance. Animals were made tolerant to one of a number of opioids of varying efficacy (low-efficacy meperidine, moderate-efficacy morphine and fentanyl, and high-efficacy [D-Ala2, N-MePhe4, Gly-ol]-enkephalin (DAMGO)) over an 8 hour period and then were administered one of the kinases’ inhibitors. Tolerance reversal was determined by challenging these mice with the same opioids to which they were tolerant. Calcium is known to play an important role in the acute antinociceptive actions of opioids as well as in opioid tolerance. Therefore it is important to determine how opioids are affecting the regulation of intracellular calcium. Our laboratory has previously shown that Calcium Induced Calcium Release (CICR), the ryanodine receptor and intracellular microsomal Ca2+ pools all play a role in opioids’ actions. It is also well known that mammalian ADP-ribosyl cyclase, CD38’s, product cADPR acts on the ryanodine receptor to cause Ca2+ release into the intracellular space. We chemically and genetically altered CD38 and then tested the acute effect of morphine as well as what effect these treatments had on morphine tolerance to determine what role if any, that CD38 may play in the acute actions of morphine antinociception as well as in morphine tolerance. Together, studies focusing on the role of an ADP-ribosyl cyclase, CD38, and 3 separate kinases, PKA, PKC and GRK, in opioids’ actions were performed in order to better understand the roles of these enzymes’ pathways in the actions of opioid-induced antinociception and subsequent development of tolerance. It is hoped that the results herein add useful knowledge to the general understanding of this drug class, and will one day be of use in the development of future analgesics and in the clinical treatment of pain and reduction in tolerance.
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Quantitative Determination of Surface Markers on B-cell Chronic Lymphocytic Leukemia (CLL) CellsNiu, Suli 30 April 2014 (has links)
To supplement and modify the diagnosis and clinical research of B-cell Chronic Lymphocytic Leukemia (B-CLL), a new method based on cell imaging and image processing was developed and applied to the B-CLL patient samples. The fluorophore-labelled leukemia cells were clearly visualized, reflecting the positive/negative expression of the corresponding surface markers and their distribution. Computer algorithms were devised and used to analyze a large number of images. The fluorescence intensity of the labelled antibodies on a given cell directly reflects the expression of the corresponding surface markers. The morphology and size of leukemia cells were not identical even in the same patient’s sample and the size variation does not correlate with the number of surface markers. The amount of each surface marker was approximately fixed for each patient, but there were some relationships, for instance, the number of CD19 and CD38 markers were correlated to each other. The heterogeneous expression of surface markers confirmed an assumption that surface markers have their preferred membrane positions. One of the most important results is that the cell imaging and our image processing method has provided an alternative and reliable way to diagnose B-CLL and new insights in the prognosis of subtype of B-CLL.
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Quantitative Determination of Surface Markers on B-cell Chronic Lymphocytic Leukemia (CLL) CellsNiu, Suli January 2014 (has links)
To supplement and modify the diagnosis and clinical research of B-cell Chronic Lymphocytic Leukemia (B-CLL), a new method based on cell imaging and image processing was developed and applied to the B-CLL patient samples. The fluorophore-labelled leukemia cells were clearly visualized, reflecting the positive/negative expression of the corresponding surface markers and their distribution. Computer algorithms were devised and used to analyze a large number of images. The fluorescence intensity of the labelled antibodies on a given cell directly reflects the expression of the corresponding surface markers. The morphology and size of leukemia cells were not identical even in the same patient’s sample and the size variation does not correlate with the number of surface markers. The amount of each surface marker was approximately fixed for each patient, but there were some relationships, for instance, the number of CD19 and CD38 markers were correlated to each other. The heterogeneous expression of surface markers confirmed an assumption that surface markers have their preferred membrane positions. One of the most important results is that the cell imaging and our image processing method has provided an alternative and reliable way to diagnose B-CLL and new insights in the prognosis of subtype of B-CLL.
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New mechanisms in nitric oxide synthase related endothelial dysfunction in the isolated heartReyes, Levy Austin 26 June 2012 (has links)
No description available.
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"Expressão de Zap-70 e CD38 em leucemia linfocítica crônica (LLC) e sua correlação com prognóstico" / Zap-70 and CD38 expression in CLL patients and the assossiation with prognosisFernandes, Margareth 19 April 2006 (has links)
Atualmente, a Leucemia Linfocítica Crônica (LLC) pode ser dividida em dois grupos: um com mutações somáticas no gene da região variável da cadeia pesada da imunoglobulina (MIgVH) e outro sem mutações (NMIgVH). Alguns estudos mostraram que a expressão de CD38 na superfície das células B de LLC pode estar correlacionada com o estado mutacional do gene VHIg, entretanto, esses controversos. Estudos recentes mostraram que a expressão da proteína tirosina quinase Zap-70 está melhor associada com o estado mutacional do gene IgVH. O objetivo deste estudo foi avaliar a expressão de Zap-70 e CD38, por citometria de fluxo, nas células CD19+ de pacientes com LLC e correlacioná-los com o estádio clínico (EC), sobrevida livre de tratamento (SLT) e sobrevida global (SG). A expressão de Zap-70 e CD38 foi avaliada, em 144 de pacientes com LLC classificados nos estádios clínicos A, B e C de acordo com os critérios de Binet: 59 (41%) do EC-A, 38 (26%) do EC-B e 47 (33%) do EC-C. Foi observada menor positividade para Zap-70 e CD38 nos pacientes do EC-A do que nos EC-B e C. Quando avaliada a SLT nos pacientes do EC-A, os casos Zap-70+ assim como os CD38+ apresentaram menor SLT. A média de SG dos pacientes Zap-70+ e CD38+ foi menor quando comparado com os Zap-70- e CD38- entretanto quando correlacionada com o EC não foi observada diferença estatisticamente significante entre a expressão desses marcadores e o EC-A, B ou C. Pela analise combinada de CD38 e Zap-70, dividimos os pacientes em dois grupos (Zap-70-/CD38- e Zap-70+ ou CD38+). Observamos que a expressão positiva desses dois marcadores estava associada ao EC, uma vez que a grande maioria dos pacientes dos estádios B (74%) e C (66%) expressam Zap-70 ou CD38. Entretanto, os pacientes do EC-A, Zap-70+ ou CD38+, apresentaram SG menor quando comparado com os Zap-70-/CD38-. Essa diferença não foi observada nos pacientes do EC-B e do EC-C. Também foi observada menor SLT nos pacientes no EC-A, Zap-70+ ou CD38+. Esses resultados sugerem que análise combinada de Zap-70 e CD38 podem ser empregadas na avaliação dos pacientes do EC-A para se acompanhar a evolução clinica desse grupo de pacientes. Porém, estudos adicionais devem ser realizados para se validar a utilização clínica desses marcadores. / Actually, chronic lymphocytic leukemia (CLL) can be divided in two subsets: one with somatically mutated immunoglobulin heavy-chain variable-region genes (MIgVH) and other with unmutated sequences. (UMIgVH). Some studies have shown that CD38 expression in CLL cells are correlated with IgVH mutational status. However, the value of CD38 as surrogate IgVH mutational status is controversial. Recent studies, have found that Zap-70 protein tyrosine kinase expression is strongly associated with the mutational status IgVH. The aim of this study was to evaluate the Zap-70 and CD38 expression, for flow cytometry, in CD19+ LLC cells and correlate with the Binets staging system, treatment-free survival (TFS) and a overall survival (OS). Zap-70 and CD38 was evaluated, in 144 CLL patients that was classified in A, B and C Binets staging system: 59 (41%) in stage A, 38 (26%) in B and 47 (33%) in C. We observed low Zap-70 and CD38 expression in stage A patients than in stage B and C cases. When we analyzed the TFS in stage A patients Zap-70+ and CD38+ patients showed shorter TFS than Zap-70- and CD38-. Then we observed that the OS of Zap-70+ and CD38+ patients was, also, shorter than Zap-70- and CD38- cases. However, statistical differences was not found when Zap-70 and CD38 expression was correlated with stage A, B or C Binets staging system. To understand the associated Zap-70 and CD38 expression, we divided the CLL patients in two subgroups (Zap-70-/CD38 - and Zap-70+ or CD38+). We observed that CD38+ or Zap-70+ was associated Binets staging system, once most of stage B (74%) and C (66%) patients are Zap-70+ or CD38+. However, stage A patients, Zap-70+ or CD38+, showed shorter OS than Zap-70-/CD38-. These differences were not observed in stage B and C patients. Shorter TFS was also observed in the Zap-70+ or CD38+ stage A patients. These results suggest that combined analysis of Zap-70 and CD38 can be used to evaluate stage A patients to observe the clinical evolution of the disease. Nevertheless, other studies must be carried to confirm the clinical use of these markers.
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Perfil clínico-laboratorial e associação com fatores prognósticos de pacientes com leucemia linfocítica crônica / Clinical laboratory profile and association of prognostic factors for patients with chronic lymphocytic leukemiaChiarelli, Maria Catarina Silveira 30 January 2012 (has links)
Chronic Lymphocytic Leukemia is the primary lymphoid neoplasm in adults and and it is
especially manifested in the elderly. Because it is a heterogeneous disease it awakens great
interest regarding its prognosis. Rai and Binet developed staging systems to predict the
evolution of the disease and currently, the analysis of expression of CD38 and Zap-70 has
been investigated as a prognostic factor for indicating presence or absence of the mutation in
the gene IgVH, so, the objective of this study was to analyze the clinical and laboratory
profiles of patients with Chronic Lymphocytic Leukemia taking as reference the clinical
staging of Rai and Binet and quantification of CD38 and Zap-70 expression as prognosis
factors. We searched the medical records of 64 patients treated at University Hospital of Santa
Maria and the variables considered were swollen lymph nodes, presence or absence of
hepatomegaly and / or splenomegaly, hematological evaluation of peripheral blood and
immunophenotype. The data obtained were correlated with the staging of Rai (1975) and
Binet (1981), the expression of CD38 and Zap-70 and clinical stage. The results showed no
association between ataging Rai and Binet and the expression of CD38, Zap-70 and Binet
clinical staging. / A Leucemia Linfocítica Crônica é a principal neoplasia linfóide em adultos e se manifeta
principalmente em indivíduos idosos. Por ser uma doença heterogênea, desperta grande
interesse quanto ao seu prognóstico. Rai e Binet desenvolveram sistemas de estadiamento
capazes de prever a evolução da doença e atualmente, a análise da expressão de CD38 e Zap-
70 tem sido investigada como fator prognóstico por indicar presença ou ausência da mutação
no gene IgVH, assim, o objetivo deste estudo foi analisar o perfil clínico-laboratorial dos
pacientes com Leucema Linfocítica Crônica, tomando como referência os estadiamentos
clínicos de Rai e Binet e a quantificação da expressão de CD38 e Zap-70 como fatores
prognóstico. Foram pesquisados 64 prontuários médicos de pacientes atendidos no Hospital
Universitário de Santa Maria e as variáveis consideradas foram aumento de linfonodos,
presença ou ausência de hepatomegalia e/ou esplenomegalia, avaliação hematológica de
sangue periférico e imunofenótipo. Os dados obtidos foram correlacionados com o
estadiamento de Rai (1975) e Binet (1981), a expressão de CD38 e Zap-70 com o estádio
clínico de Binet. Os resultados demonstraram que não há associação entre o estadiamento de
Raí e Binet e a expressão de CD38, Zap-70 com o estadiamento clínico de Binet.
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"Expressão de Zap-70 e CD38 em leucemia linfocítica crônica (LLC) e sua correlação com prognóstico" / Zap-70 and CD38 expression in CLL patients and the assossiation with prognosisMargareth Fernandes 19 April 2006 (has links)
Atualmente, a Leucemia Linfocítica Crônica (LLC) pode ser dividida em dois grupos: um com mutações somáticas no gene da região variável da cadeia pesada da imunoglobulina (MIgVH) e outro sem mutações (NMIgVH). Alguns estudos mostraram que a expressão de CD38 na superfície das células B de LLC pode estar correlacionada com o estado mutacional do gene VHIg, entretanto, esses controversos. Estudos recentes mostraram que a expressão da proteína tirosina quinase Zap-70 está melhor associada com o estado mutacional do gene IgVH. O objetivo deste estudo foi avaliar a expressão de Zap-70 e CD38, por citometria de fluxo, nas células CD19+ de pacientes com LLC e correlacioná-los com o estádio clínico (EC), sobrevida livre de tratamento (SLT) e sobrevida global (SG). A expressão de Zap-70 e CD38 foi avaliada, em 144 de pacientes com LLC classificados nos estádios clínicos A, B e C de acordo com os critérios de Binet: 59 (41%) do EC-A, 38 (26%) do EC-B e 47 (33%) do EC-C. Foi observada menor positividade para Zap-70 e CD38 nos pacientes do EC-A do que nos EC-B e C. Quando avaliada a SLT nos pacientes do EC-A, os casos Zap-70+ assim como os CD38+ apresentaram menor SLT. A média de SG dos pacientes Zap-70+ e CD38+ foi menor quando comparado com os Zap-70- e CD38- entretanto quando correlacionada com o EC não foi observada diferença estatisticamente significante entre a expressão desses marcadores e o EC-A, B ou C. Pela analise combinada de CD38 e Zap-70, dividimos os pacientes em dois grupos (Zap-70-/CD38- e Zap-70+ ou CD38+). Observamos que a expressão positiva desses dois marcadores estava associada ao EC, uma vez que a grande maioria dos pacientes dos estádios B (74%) e C (66%) expressam Zap-70 ou CD38. Entretanto, os pacientes do EC-A, Zap-70+ ou CD38+, apresentaram SG menor quando comparado com os Zap-70-/CD38-. Essa diferença não foi observada nos pacientes do EC-B e do EC-C. Também foi observada menor SLT nos pacientes no EC-A, Zap-70+ ou CD38+. Esses resultados sugerem que análise combinada de Zap-70 e CD38 podem ser empregadas na avaliação dos pacientes do EC-A para se acompanhar a evolução clinica desse grupo de pacientes. Porém, estudos adicionais devem ser realizados para se validar a utilização clínica desses marcadores. / Actually, chronic lymphocytic leukemia (CLL) can be divided in two subsets: one with somatically mutated immunoglobulin heavy-chain variable-region genes (MIgVH) and other with unmutated sequences. (UMIgVH). Some studies have shown that CD38 expression in CLL cells are correlated with IgVH mutational status. However, the value of CD38 as surrogate IgVH mutational status is controversial. Recent studies, have found that Zap-70 protein tyrosine kinase expression is strongly associated with the mutational status IgVH. The aim of this study was to evaluate the Zap-70 and CD38 expression, for flow cytometry, in CD19+ LLC cells and correlate with the Binets staging system, treatment-free survival (TFS) and a overall survival (OS). Zap-70 and CD38 was evaluated, in 144 CLL patients that was classified in A, B and C Binets staging system: 59 (41%) in stage A, 38 (26%) in B and 47 (33%) in C. We observed low Zap-70 and CD38 expression in stage A patients than in stage B and C cases. When we analyzed the TFS in stage A patients Zap-70+ and CD38+ patients showed shorter TFS than Zap-70- and CD38-. Then we observed that the OS of Zap-70+ and CD38+ patients was, also, shorter than Zap-70- and CD38- cases. However, statistical differences was not found when Zap-70 and CD38 expression was correlated with stage A, B or C Binets staging system. To understand the associated Zap-70 and CD38 expression, we divided the CLL patients in two subgroups (Zap-70-/CD38 - and Zap-70+ or CD38+). We observed that CD38+ or Zap-70+ was associated Binets staging system, once most of stage B (74%) and C (66%) patients are Zap-70+ or CD38+. However, stage A patients, Zap-70+ or CD38+, showed shorter OS than Zap-70-/CD38-. These differences were not observed in stage B and C patients. Shorter TFS was also observed in the Zap-70+ or CD38+ stage A patients. These results suggest that combined analysis of Zap-70 and CD38 can be used to evaluate stage A patients to observe the clinical evolution of the disease. Nevertheless, other studies must be carried to confirm the clinical use of these markers.
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Telomere length as prognostic parameter in chronic lymphocytic leukemiaGrabowski, Pawel January 2011 (has links)
B-cell chronic lymphocytic leukemia (B-CLL) is the most common leukemia among the adult population in western countries and accounts for 30-40% of all leukemias. With survival time ranging from months to decades, the clinical course of individual CLL patients is highly variable. This heterogeneity and in the end the need for means to identify the patients with less favorable disease has encouraged the search for biomarkers that can predict the prognosis. Telomeres are repetitive structures protecting the chromosomal endings and shorten at each cell division. Telomere length (TL) has been indicated as a prognostic factor both in hematological malignancies and solid tumors. In B-CLL, TL is associated with mutation status of the immunoglobulin heavy chain variable (IGHV) gene and with clinical course. In the present thesis the main aim was to evaluate TL as a biomarker in B-CLL using a quantitative PCR-based method for TL determination. In paper I, TL was shown to be a prognostic factor for stage A and stage B/C patients, whereas IGHV mutation status predicted outcome only in stage A patients. Moreover, IGHV mutated CLL cases were subdivided by TL into two groups with different prognosis, a subdivision not seen for unmutated cases. Interestingly, the IGHV-mutated group with short telomeres had en overall survival close to that of the unmutated cases. Thus, a combination of IGHV mutation status and telomere length gave an improved subclassification of CLL identifying previously unrecognized patient groups with different outcomes. TL correlates with cellular origin of B-cell malignancies in relation to the germinal center (GC). In paper II different B-cell lymphoma/leukemia subtypes were analyzed. Shortest telomeres were found in IGHV unmutated CLLs, differing significantly from IGHV mutated cases. Contrary to this, mantle cell lymphomas (MCL) demonstrated similar TL regardless of IGHV mutation status. TL differed significantly between GC-like and non-GC-like diffuse large B-cell lymphomas (DLBCL) and follicular lymphomas (FL) had shorter telomeres than GC-like DLBCL. Hairy cell leukemias, which display Ig gene intraclonal heterogeneity, had longer telomeres than FLs and non-GC-DLBCL, but shorter than GC-DLBCL. In conclusion, TL seemed not to simply correlate with GC origin. Paper III presents a B-CLL cohort assessed for TL, genomic aberrations, IGHV mutation status, CD38 and ZAP-70 expression. An inverse correlation existed between TL and IGHV homology, CD38 and ZAP-70 expression. The presence of genomic aberrations was similar among patients regardless of TL. In contrast, 13q deletion, a favorable biomarker, was more frequent in patients with long telomeres, while 11q and 17p deletions (markers of less favorable outcome) were more frequent in the subgroup with short telomeres. In paper IV a large group of mainly indolent CLL cases from a population based cohort was studied again showing an association between TL and prognosis, especially in “good” prognosis cases as defined by other biomarkers. Multivariate analysis indicated a strong connection between IGHV mutation status, lipoprotein lipase (LPL) expression and TL. A comparison of TL in diagnostic and follow up samples demonstrated a significant correlation, and also in the follow samples TL constituted a significant biomarker for survival.
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Vybrané aspekty imunopatogeneze HIV infekce / Selected aspects of immunopathogenesis of HIV infectionBartovská, Zofia January 2011 (has links)
Introduction: Virus-specific CD8+ T cells are crucial to suppress the viral replication in HIV infection. Their functional status is important as well. Also, the chronic nonspecific immune activation of T and B lymphocytes plays an important role in the immunopathogenesis of HIV infection. Aim of the study: To analyze the frequency and functional status of HIV-specific CD8+ T cells and the expression of nonspecific activation markers on B and T cells in HIV+ patients and to assess the effect of combined antiretroviral therapy (cART) on these parameters. Patients and methods: Our cohort included 80 HIV+ patients: 36 HIV+ patients on cART, 18 patients without therapy, in whom cART was introduced during our study, 9 patients without therapy, 10 patients with primary HIV infection, 3 long-term non-progressors and 4 patients initially on cART, in whom the therapy was discontinued. Control group consisted of 34 HIV- healthy individuals. We examined CD4+ a CD8+ T cell counts, viral load, expression of nonspecific activation markers on T cells and the frequency of HIV-specific CD8+ T cells by ELISpot method and flow cytometry using MHC tetramers and intracellular cytokine detection. Results: No significant differences in HIV-specific CD8+ T cells were found between treated and untreated HIV+ patients. The frequency...
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Vybrané aspekty imunopatogeneze HIV infekce / Selected aspects of immunopathogenesis of HIV infectionBartovská, Zofia January 2011 (has links)
Introduction: Virus-specific CD8+ T cells are crucial to suppress the viral replication in HIV infection. Their functional status is important as well. Also, the chronic nonspecific immune activation of T and B lymphocytes plays an important role in the immunopathogenesis of HIV infection. Aim of the study: To analyze the frequency and functional status of HIV-specific CD8+ T cells and the expression of nonspecific activation markers on B and T cells in HIV+ patients and to assess the effect of combined antiretroviral therapy (cART) on these parameters. Patients and methods: Our cohort included 80 HIV+ patients: 36 HIV+ patients on cART, 18 patients without therapy, in whom cART was introduced during our study, 9 patients without therapy, 10 patients with primary HIV infection, 3 long-term non-progressors and 4 patients initially on cART, in whom the therapy was discontinued. Control group consisted of 34 HIV- healthy individuals. We examined CD4+ a CD8+ T cell counts, viral load, expression of nonspecific activation markers on T cells and the frequency of HIV-specific CD8+ T cells by ELISpot method and flow cytometry using MHC tetramers and intracellular cytokine detection. Results: No significant differences in HIV-specific CD8+ T cells were found between treated and untreated HIV+ patients. The frequency...
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