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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.
1

A Study of the prognostic value of B[beta]2 microglobulin in nasopharyngeal carcinoma.

January 1991 (has links)
by Hiu Wong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1991. / Includes bibliographical references. / SUMMARY --- p.1 / INTRODUCTION --- p.4 / LITERATURE REVIEW --- p.8 / Chapter I. --- Nasopharyngeal carcinoma (NPC) --- p.8 / Chapter A. --- Epidemiology of NPC --- p.8 / Chapter B. --- Anatomy of NPC --- p.11 / Chapter C. --- Pathology of NPC --- p.12 / Chapter D. --- Histological classification of NPC --- p.14 / Chapter E. --- Stage classification of NPC --- p.15 / Chapter F. --- Clinical feature of NPC --- p.18 / Chapter G. --- Diagnosis of NPC --- p.19 / Chapter (a) --- Clinical examination / Chapter (b) --- Radiographic examination / Chapter (c) --- Laboratory examination / Chapter (d) --- Biopsy examination / Chapter H. --- Treatment of NPC --- p.21 / Chapter (a) --- Surgery / Chapter (b) --- Chemotherapy / Chapter (c) --- Radiotherapy / Chapter I. --- Prognosis of NPC --- p.23 / Chapter J. --- Etiology of NPC --- p.24 / Chapter (a) --- Dietary factor / Chapter (b) --- Genetic factor / Chapter (c) --- Environmental factor / Chapter (d) --- EBV infection / Chapter (e) --- Others / Chapter II. --- Beta-2 Microglobulin (B2M) --- p.30 / Chapter A. --- Structure and function of B2M --- p.30 / Chapter B. --- Clinical chemistry of B2M --- p.33 / Chapter C. --- B2M and its relationship to immunogenetic system --- p.34 / Chapter D. --- B2M in solid malignancies --- p.35 / Chapter E. --- B2M in hematologic malignancies --- p.36 / Chapter F. --- B2M in non-malignant diseases --- p.38 / Chapter III. --- Epstein - Barr Virus (EBV) --- p.41 / Chapter A. --- Morphology / Chapter B. --- EBV infection --- p.42 / Chapter C. --- EBV and Nasopharyngeal Carcinoma --- p.44 / Chapter D. --- Relationship of EBV to other human disease --- p.46 / Chapter (a) --- The relationship of EBV to IM / Chapter (b) --- The relationship of EBV to BL / Chapter E. --- EBV genome-carrying lymphoid cell lines --- p.50 / Chapter IV. --- TUMOUR ANTIGEN OF SQUEMOUS CELL CARCINOMA --- p.55 / Chapter A. --- The source of TA-4 --- p.55 / Chapter B. --- Characteristics of TA-4 --- p.56 / Chapter C. --- TA-4 in squamous cell carcinoma of uterine cervix --- p.57 / Chapter D. --- TA-4 in other type of squamous cell carcinaoma --- p.58 / MATERIALS AND METHODS / Chapter A. --- Materials --- p.61 / Chapter B. --- Measurement of Beta-2 Microglobulin --- p.63 / Chapter (a) --- Principles / Chapter (b) --- Assay protocol / Chapter (c) --- Reproducibility / Chapter C. --- Detection of EBV antibody titres in human sera --- p.68 / Chapter (a) --- Induction of EA/VCA in Raji/P3HR-1 cell lines / Chapter (b) --- Detection of antibody titres to EA/VCA in human sera / Chapter D. --- Measurement of squamous cell carcinoma associated antigen --- p.75 / RESULTS --- p.79 / Chapter A. --- Diurnal change of serum B2M or TA-4 level --- p.79 / Chapter B. --- The B2M and TA-4 levels in apparently healthy people --- p.81 / Chapter C. --- The usefullness of assay in initial diagnosis and staging --- p.81 / Chapter (a) --- Correlation between serum B2M levels and staging of NPC / Chapter (b) --- Correlation between serum TA-4 levels and staging of NPC / Chapter D. --- Correlation between histological differentiation of NPC and B2M and TA-4 level --- p.91 / Chapter E. --- The usefulness of assay for monitoring the NPC --- p.93 / Chapter (a) --- patients achieved completed remission / Chapter (b) --- patients developed local recurrence / Chapter (c) --- patients developed distant metastases / DISCUSSION --- p.131 / Chapter A. --- Serum B2M in NPC patients --- p.131 / Chapter B. --- Serum TA-4 in NPC ptients --- p.136 / Chapter C. --- EBV antibody titres in NPC patients --- p.137 / Chapter D. --- Conclusion --- p.141 / Chapter E. --- Suggested further study --- p.143 / REFERENCES --- p.146
2

ß-2 microglobulina e citocinas séricas como indicadores de falha terapêutica aos anti-retrovirais /

Almeida, Ricardo Augusto Monteiro de Barros. January 2009 (has links)
Orientador: Domingos Alves Meira / Banca: Rogério de Jesus Pedro / Banca: David Salomão Lewi / Banca: Alexandrina Sartori / Banca: Maria Inês de Moura Campos Pardini / Resumo: Iniciativas como a "WHO/UNAIDS '3 by 5' permitiram que se atingisse, no ano de 2007, a marca de 3 milhões de pessoas com acesso à terapia antiretroviral (TARV) em países de baixa e média renda. O aumento da cobertura nestes países demanda custos importantes com anti-retrovirais, porém também levanta outro problema, que é o monitoramento da terapia em localidades de poucos recursos. Há consenso no fato de que devem ser pesquisados marcadores de eficácia da TARV mais acessíveis. Considerando o comportamento da β-2 microglobulina sérica e das citocinas séricas TNF-α, IFN-γ, IL-2, IL-4 e IL-10 com relação à atividade inflamatória induzida pela replicação do HIV-1, o objetivo deste estudo foi o de verificar o comportamento destas substâncias como indicadores da presença, ou não, de falha terapêutica à HAART. Entre agosto de 2004 e novembro de 2005, 89 indivíduos infectados pelo HIV-1, atendidos pela Área de Doenças Tropicais da Faculdade de Medicina de Botucatu-UNESP, e 20 indivíduos normais, doadores de sangue do Hemocentro de Botucatu [43 mulheres e 66 homens; idade média = 39,7 anos (22 - 66 anos)] foram divididos em 4 grupos: G1- 15 indivíduos infectados pelo HIV-1, virgens de tratamento ou sem HAART há pelo menos seis meses e com contagens de linfócitos T CD4 + menores que 350 células/mm3; G2- 31 indivíduos infectados pelo HIV-1, em uso de HAART e sem falha terapêutica virológica (FT); G3- formado por 43 indivíduos infectados pelo HIV-1, em uso de HAART e com FT, e GC- formado por 20 indivíduos normais, não infectados pelo HIV-1, que serviram de controles para as citocinas séricas. Foram revisados os dados demográficos, clínicos e de HAART e realizados os exames β-2 microglobulina sérica, citocinas séricas (TNF-α, IFN-γ, IL-2, IL-4 e IL-10), genotipagem do HIV-1, carga viral plasmática (CV) e linfócitos T CD4 + e T CD8 +. Para... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Initiatives such as WHO/UNAIDS '3 by 5' made it possible to achieve the figure of 3 million people with access to antiretroviral therapy (ART) in middle- and low-income countries in 2007. The increase in these countries' coverage leads to important expenditure on antiretroviral drugs; however, it also raises another problem, which is therapy monitoring in low-income locations. There is agreement on the fact that more accessible ART efficacy markers must be studied. By considering the behavior of serum β-2 microglobulin and serum cytokines TNF-α, IFN-γ, IL-2, IL-4 and IL-10 in relation to inflammatory activity induced by HIV-1 replication, the objective of this study was to assess the behavior of such substances as indicators of the presence, or not, of antiretroviral therapeutic failure (TF). From August 2004 to November 2005, 89 HIV-1-infected individuals assisted by the Tropical Diseases Sector of the Botucatu School of Medicine - UNESP and 20 normal blood donors at the Blood Transfusion Center of Botucatu [43 female and 66 male; mean age = 39.7 years (22 - 66 years)] were divided into 4 groups: G1- 15 HIV-1-infected individuals, previously untreated or without HAART for at least six months and CD4 + < 350 cells/mm3; G2- 31 HIV-1-infected individuals undergoing HAART without virological therapeutic failure (TF), G3- 43 HIV-1-infected individuals undergoing HAART with TF, and CG- 20 normal individuals who served as controls for serum cytokines. Demographic, clinical and HAART data were reviewed, and serum β-2 microglobulin, serum cytokines (TNFα, IFN-γ, IL-2, IL-4 and IL-10), HIV-1 genotyping, plasma viral load (VL) and T CD4 + and T CD8 + lymphocytes tests were performed. The Mann-Whitney test for independent samples was used for between-group comparison in the case of numeric variables, and Fisher's exact test was applied for category variables. Statistical difference... (Complete abstract click electronic access below) / Doutor
3

A Systematic Investigation into the Effect of Protein Destabilisation on Beta 2-Microglobulin Amyloid Formation

Jones, Susan, Smith, D.P., Serpell, L.C, Sunde, M., Radford, S.E. 20 July 2009 (has links)
No / Beta-2-microglobulin (2m) has been shown to form amyloid fibrils with distinct morphologies under acidic conditions in vitro. Short, curved fibrils (<600 nm in length), form rapidly without a lag phase, with a maximum rate at pH 3.5. By contrast, fibrils with a long (~1 m), straight morphology are produced by incubation of the protein at pH=<3.0. Both fibril types display Congo red birefringence, bind Thioflavin-T and have X-ray fibre diffraction patterns consistent with a cross-beta structure. In order to investigate the role of different partially folded states in generating fibrils of each type, and to probe the effect of protein stability on amyloid formation, we have undertaken a detailed mutagenesis study of 2m. Thirteen variants containing point mutations in different regions of the native protein were created and their structure, stability and fibril forming propensities were investigated as a function of pH. By altering the stability of the native protein in this manner, we show that whilst destabilisation of the native state is important in the generation of amyloid fibrils, population of specific denatured states is a pre-requisite for amyloid formation from this protein. Moreover, we demonstrate that the formation of fibrils with different morphologies in vitro correlates with the relative population of different precursor states.
4

Study of the Association of Plasma Neutrophil Gelatinase-Associated Lipocalin(NGAL) and £]2-Microglobulin Level with Diabetic Nephropathy.

Lo, Shu-Yi 10 February 2011 (has links)
Diabetic nephropathy is a common diabetic microvascular disease with a prevalence of about 10% to 42%. Research has shown that neutrophil gelatinase-associated lipocalin (NGAL) levels would increase rapidly in the urine and blood of patients with acute kidney failure. NGAL may represent an early and predictive kidney injury biomarker due to the increase of NGAL occurs earlier than that of molecules (creatinine, cystatin C and £]2-microglobulin) for traditional assessment of renal injury in renal disease samples. To evaluate the association of plasma level of NGAL and £]2-microglobulin with diabetic nephropathy, this study was performed on 21 diabetic patients without nephropathy as the control group and 21 patients with diabetic nephropathy stage 2, 26 patients with stage 3, 9 patients with stage 4 and 16 patients stage 5 as the study group. Collection of blood and measurements of all cases were approved by the ethical committee. The results indicate that the levels of blood urea nitrogen (BUN), creatinine, NGAL, and £]2-microglobulin of study group were significantly higher than control group (P<0.001), while the glomerular filtration rate (GFR) was significantly lower than the control group (P<0.001). Linear regression analysis show that NGAL was positively correlated with white blood cells, BUN, creatinine, £]2-micrglobulin and negatively correlated with GFR; and £]2-micrglobulin was positively correlated with BUN, creatinine, NGAL and negatively correlated with GFR. All results indicate that plasma NGAL levels in diabetic nephropathy were positively correlated with renal function parameters, and closely correlated with kidney injury, suggesting that NGAL may play an important role in the progression of diabetic nephropathy.
5

Interactions of MHC class I molecules with peptide ligands and [beta]₂-microglobulin /

Robinson-Smith, Ruth A. January 1996 (has links)
Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / "December 1996." Typescript. Vita. Includes bibliographical references (leaves [128]-155). Also available on the Internet.
6

ß-2 microglobulina e citocinas séricas como indicadores de falha terapêutica aos anti-retrovirais

Almeida, Ricardo Augusto Monteiro de Barros [UNESP] 26 February 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:31:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-26Bitstream added on 2014-06-13T20:41:51Z : No. of bitstreams: 1 almeida_ramb_dr_botfm.pdf: 853261 bytes, checksum: 866edf2277c1ac0e74ea9c48e8cb31a9 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Iniciativas como a “WHO/UNAIDS ‘3 by 5’ permitiram que se atingisse, no ano de 2007, a marca de 3 milhões de pessoas com acesso à terapia antiretroviral (TARV) em países de baixa e média renda. O aumento da cobertura nestes países demanda custos importantes com anti-retrovirais, porém também levanta outro problema, que é o monitoramento da terapia em localidades de poucos recursos. Há consenso no fato de que devem ser pesquisados marcadores de eficácia da TARV mais acessíveis. Considerando o comportamento da β-2 microglobulina sérica e das citocinas séricas TNF-α, IFN-γ, IL-2, IL-4 e IL-10 com relação à atividade inflamatória induzida pela replicação do HIV-1, o objetivo deste estudo foi o de verificar o comportamento destas substâncias como indicadores da presença, ou não, de falha terapêutica à HAART. Entre agosto de 2004 e novembro de 2005, 89 indivíduos infectados pelo HIV-1, atendidos pela Área de Doenças Tropicais da Faculdade de Medicina de Botucatu-UNESP, e 20 indivíduos normais, doadores de sangue do Hemocentro de Botucatu [43 mulheres e 66 homens; idade média = 39,7 anos (22 - 66 anos)] foram divididos em 4 grupos: G1- 15 indivíduos infectados pelo HIV-1, virgens de tratamento ou sem HAART há pelo menos seis meses e com contagens de linfócitos T CD4 + menores que 350 células/mm3; G2- 31 indivíduos infectados pelo HIV-1, em uso de HAART e sem falha terapêutica virológica (FT); G3- formado por 43 indivíduos infectados pelo HIV-1, em uso de HAART e com FT, e GC- formado por 20 indivíduos normais, não infectados pelo HIV-1, que serviram de controles para as citocinas séricas. Foram revisados os dados demográficos, clínicos e de HAART e realizados os exames β-2 microglobulina sérica, citocinas séricas (TNF-α, IFN-γ, IL-2, IL-4 e IL-10), genotipagem do HIV-1, carga viral plasmática (CV) e linfócitos T CD4 + e T CD8 +. Para... / Initiatives such as WHO/UNAIDS ‘3 by 5’ made it possible to achieve the figure of 3 million people with access to antiretroviral therapy (ART) in middle- and low-income countries in 2007. The increase in these countries’ coverage leads to important expenditure on antiretroviral drugs; however, it also raises another problem, which is therapy monitoring in low-income locations. There is agreement on the fact that more accessible ART efficacy markers must be studied. By considering the behavior of serum β-2 microglobulin and serum cytokines TNF-α, IFN-γ, IL-2, IL-4 and IL-10 in relation to inflammatory activity induced by HIV-1 replication, the objective of this study was to assess the behavior of such substances as indicators of the presence, or not, of antiretroviral therapeutic failure (TF). From August 2004 to November 2005, 89 HIV-1-infected individuals assisted by the Tropical Diseases Sector of the Botucatu School of Medicine – UNESP and 20 normal blood donors at the Blood Transfusion Center of Botucatu [43 female and 66 male; mean age = 39.7 years (22 - 66 years)] were divided into 4 groups: G1- 15 HIV-1-infected individuals, previously untreated or without HAART for at least six months and CD4 + < 350 cells/mm3; G2- 31 HIV-1-infected individuals undergoing HAART without virological therapeutic failure (TF), G3- 43 HIV-1-infected individuals undergoing HAART with TF, and CG- 20 normal individuals who served as controls for serum cytokines. Demographic, clinical and HAART data were reviewed, and serum β-2 microglobulin, serum cytokines (TNFα, IFN-γ, IL-2, IL-4 and IL-10), HIV-1 genotyping, plasma viral load (VL) and T CD4 + and T CD8 + lymphocytes tests were performed. The Mann-Whitney test for independent samples was used for between-group comparison in the case of numeric variables, and Fisher’s exact test was applied for category variables. Statistical difference... (Complete abstract click electronic access below)
7

Structural Characterization of the Pre-Amyloid Oligomers of β-2-Microglobulin Using Covalent Labeling and Mass Spectrometry

Mendoza, Vanessa Leah Castillo 01 September 2010 (has links)
The initial steps involved in the assembly of normally soluble proteins into amyloid fibrils remain unclear, yet over 20 human diseases are associated with proteins that aggregate in this manner. Protein surface modification is a potential means of mapping the interaction sites in early oligomers that precede amyloid formation. This dissertation focuses on the use of covalent labeling combined with mass spectrometry to elucidate the structural features of Cu(II)-induced β-2-microglobulin (β2m) amyloid formation. An improved covalent modification and MS-based approach for protein surface mapping has been developed to address the need for a reliable approach that ensures protein structural integrity during labeling experiments and provides readily detectable modifications. This approach involves measuring the kinetics of the modification reactions and allows any local perturbations caused by the covalent label to be readily identified and avoided. This MS-based method has been used to study human β2m, a monomeric protein that has been shown to aggregate into amyloid fibrils in dialysis patients leading to dialysis-related amyloidosis. Under conditions that lead to β2m amyloid formation, reactions of β2m with three complementary covalent labels have been used to identify the Cu(II) binding site, metal-induced conformational changes, and the oligomeric interfaces. Results confirm that Cu(II) binds to His31 and the N-terminal amine. Binding to these residues causes several structural changes in the N-terminal region and ABED β-sheet which likely enables formation of oligomeric intermediates. The covalent labeling data indicate that the pre-amyloid β2m dimer has an interface that involves the antiparallel arrangement of ABED sheets from two monomers. Moreover, our covalent labeling data allowed us to develop a model for the tetramer in which the interface is mediated by interactions between D strands of one dimer unit and the G strands of another dimer unit. Lastly, the selective covalent modification approach has been used to delineate the structural changes in β2m after interaction with Cu(II), Ni(II), and Zn(II) and their effect on its aggregation. Our covalent labeling data indicates that the unique effect of Cu(II) appears to be caused by the site at which the metal binds the protein and the conformational changes it induces.
8

Role of the N- and C-terminal strands of beta 2-microglobulin in amyloid formation at neutral pH.

Jones, Susan, Smith, D.P., Radford, S.E. January 2003 (has links)
No / Beta 2-microglobulin (ß2m) is known to form amyloid fibrils de novo in vitro under acidic conditions (below pH 4.8). Fibril formation at neutral pH, however, has only been observed by deletion of the N-terminal six residues; by the addition of pre-assembled seeds; or in the presence of Cu2+. Based on these observations, and other structural data, models for fibril formation of ß2m have been proposed that involve the fraying of the N and C-terminal ß-strands and the consequent loss of edge strand protective features. Here, we examine the role of the N and C-terminal strands in the initiation of fibrillogenesis of ß2m by creating point mutations in strands A and G and comparing the properties of the resulting proteins with variants containing similar mutations elsewhere in the protein. We show that truncation of buried hydrophobic side-chains in strands A and G promotes rapid fibril formation at neutral pH, even in unseeded reactions, and increases the rate of fibril formation under acidic conditions. By contrast, similar mutations created in the remaining seven ß-strands of the native protein have little effect on the rate or pH dependence of fibril formation. The data are consistent with the view that perturbation of the N and C-terminal edge strands is an important feature in the generation of assembly-competent states of ß2m.
9

β2-microglobulin distribution in trout body fluids and release from intestinal epithelial cells in response to plant meal components

Raben, Alex 07 July 2011 (has links)
β2-microglobulin (β2m) exists free of the major histocompatibility complex class I (MHC I) receptor in many bodily fluids. The amount of protein present in these fluids has been found to be a useful prognostic marker for various diseases but outside of its practical value not much is known about this form of β2m. In fish, soluble β2m has not been studied at all. Another unknown in fish is the effects that plants lectins might have on naturally carnivorous species in aquaculture. These plant proteins which bind to specific sugar groups found on cells have been shown to have a multitude of gastrointestinal and immune effects in mammals and can be found in the plant products being fed to carnivorous, cultured fish making them possible toxicants. The two studies of this thesis set out to pioneer knowledge on these subjects using rainbow trout as a model. The first investigation inspected the various body fluids of these fish for their free β2m content. Soluble β2m was found to be present in the plasma, the seminal fluid, ovarian fluid, and the mucus of the skin and intestines. This distribution shows that β2m could indeed make a good biomarker, not only for disease but also for pheromone release and alludes to some possible functions of soluble β2m while opening the way for future research on this form of the protein. The second study looked at the effects of lectins on the gut of rainbow trout by treating RTgutGC, an intestinal epithelial cell line derived from trout, with plant lectins from wheat (WGA) and soybean (SBA), among others. This study found WGA to be a potent inducer of morphological and cytotoxic effects in these cells while other lectins and plant factors were not. WGA was also observed to effect the expression of β2m and the α-chain of the MHC I receptor. This work suggests WGA ingested by trout through the wheat in their diet might be causing them harm and should be studied further. It is also interesting that both studies related β2m to the intestines of trout. This could allow soluble β2m to serves as a marker of WGA’s effect or for WGA to aid in the study of free β2m.
10

β2-microglobulin distribution in trout body fluids and release from intestinal epithelial cells in response to plant meal components

Raben, Alex 07 July 2011 (has links)
β2-microglobulin (β2m) exists free of the major histocompatibility complex class I (MHC I) receptor in many bodily fluids. The amount of protein present in these fluids has been found to be a useful prognostic marker for various diseases but outside of its practical value not much is known about this form of β2m. In fish, soluble β2m has not been studied at all. Another unknown in fish is the effects that plants lectins might have on naturally carnivorous species in aquaculture. These plant proteins which bind to specific sugar groups found on cells have been shown to have a multitude of gastrointestinal and immune effects in mammals and can be found in the plant products being fed to carnivorous, cultured fish making them possible toxicants. The two studies of this thesis set out to pioneer knowledge on these subjects using rainbow trout as a model. The first investigation inspected the various body fluids of these fish for their free β2m content. Soluble β2m was found to be present in the plasma, the seminal fluid, ovarian fluid, and the mucus of the skin and intestines. This distribution shows that β2m could indeed make a good biomarker, not only for disease but also for pheromone release and alludes to some possible functions of soluble β2m while opening the way for future research on this form of the protein. The second study looked at the effects of lectins on the gut of rainbow trout by treating RTgutGC, an intestinal epithelial cell line derived from trout, with plant lectins from wheat (WGA) and soybean (SBA), among others. This study found WGA to be a potent inducer of morphological and cytotoxic effects in these cells while other lectins and plant factors were not. WGA was also observed to effect the expression of β2m and the α-chain of the MHC I receptor. This work suggests WGA ingested by trout through the wheat in their diet might be causing them harm and should be studied further. It is also interesting that both studies related β2m to the intestines of trout. This could allow soluble β2m to serves as a marker of WGA’s effect or for WGA to aid in the study of free β2m.

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