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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

Life satisfaction: influences of family and friends upon the elderly

Barr, Cynthia A. January 1978 (has links)
The relative importance of contact with family and friends for an.elderly person's life satisfaction was investigated. A random sample of 167 noninstitutionalized elderly residents (65 and over) of Philadelphia completed an extensive in-depth interview packet. Each subject was then rated by a trained interviewer on their life satisfaction. The results indicated that increased activity with friends was directly related to the elderly person's life satisfaction, while increased family contact had a negligible effect. With the use of regression analysis, perceived health status was found to be the most salient predictor for life satisfaction, followed by friend contact intensity and objective health. In addition, the use of various specification variables, previously posited to relate with life satisfaction, did not change the initial findings of the sample. The implications of these findings for the Activity Theory of Aging were discussed. / Master of Science
2

The role of HLA-B27 in inflammatory arthritis /

Lynch, Sarah Janice. January 2008 (has links)
Thesis (Ph. D.)--University of St Andrews, February 2009. / Restricted until 23rd February 2012.
3

Frequência dos alelos do HLA-B27 em pacientes brasileiroa com artrite psoriásica / Frequency of HLA--B27 alleles in brazilian patients with psoriatic arthritis

Bonfiglioli, Rubens 16 August 2018 (has links)
Orientador: Manoel Barros Bértolo / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T11:36:12Z (GMT). No. of bitstreams: 1 Bonfiglioli_Rubens_D.pdf: 4535259 bytes, checksum: c162b3d3293837dabf58f540050f6b46 (MD5) Previous issue date: 2009 / Resumo: Este estudo prospectivo analisou a epidemiologia, clínica e perfil genético de 102 pacientes brasileiros com Artrite Psoriásica. A associação do complexo maior de histocompatibilidade (MHC) de classe I, e os alelos do HLA-B27 com aquelas variáveis foram avaliados e comparados com sadios controles, HLA-B27 positivos, compondo um grupo de 111 indivíduos. A predominância foi do sexo masculino (59,8%), raça caucasóide (89,2%) e HLA-B27 negativos (79,4%). Oligoartrite assimétrica (62,7%) foi o subgrupo de Artrite Psoriásica mais observado, seguido pela forma espondilítica (16,7%) e poliarticular (15,7%). O sexo masculino e o subgrupo dos espondilíticos foram estatisticamente mais associados ao HLA-B27, e o subgrupo oligoarticular ao HLA-B27 negativo. Entre os 21 pacientes com Artrite Psoriásica e HLA-B27 positivos existiu uma significante prevalência do HLA-B*2705 (90,5%), similar ao observado no grupo controle (80,2%); HLA-B*2703 e HLA-B*2707 foram estatisticamente associados ao grupo controle / Abstract: This prospective study analyzed the epidemiologic, clinical and genetic profile of 102 Brazilian patients with psoriatic arthritis (PsA). The association of the major histocompatibility complex (MHC) class I and the HLA-B27 alleles with these variants was outlined, and compared to a control healthy HLA-B27 positive group of 111 individuals. There was a predominance of male gender (59.8%), Caucasian race (89.2%) and negative HLA-B27 (79.4%) patients. Asymmetric oligoarthritis (62.7%) was the most frequently observed clinical PsA subgroup, followed by spondylitis (16.7%) and polyarthritis (15.7%). Male gender and the spondylitis subgroup were statistically associated to the positive HLAB27 and the oligoarthritis subgroup was associated to the negative HLA-B27. Among the 21 HLA-B27 positive PsA patients, there was a significant prevalence of the HLA-B*2705 allele (90.5 %), similar to that observed in the control group (80.2%); HLA-B*2703 and HLA-B*2707 were statistically associated to the control group. Other antigens such as HLA- B07 (14 patients), HLA-B08 (14 patients) and HLA-B44 (13 patients) among others, were found in HLA-B27-negative patients / Doutorado / Clinica Medica / Doutor em Clínica Médica
4

Particularités immunobiochimiques et trafic intracellulaire de la protéine HLA-B27, molécule du complexe majeur d'histocompatibilité de classe I impliquée dans les spondylarthrites / Immunobiochimiques features and intracellular trafficking of HLA-B27 molecule major histocompatibility complex class I involved in spondylitis

Gaspard, Cindy Jeanty 30 January 2012 (has links)
La spondylarthrite ankylosante (SA), la forme la plus commune des spondylarthrites (SpA), est fortement associée à la molécule du CMH de classe I HLA-B27 mais le rôle de cet antigène d'histocompatibilité dans le développement de ces pathologies reste encore inexpliqué. L’étude des rats transgéniques HLA-B27, développant une pathologie inflammatoire spontanée ressemblant aux SpA, a permis de confirmer l’implication directe du HLA-B27 et de corréler l’apparition des symptômes avec une forte expression de cette molécule. De plus, il a été montré que l’HLA-B27 présentait une propension particulière au mauvais repliement et à la formation d’oligomères de chaînes lourdes. L’objectif de mon travail de thèse était de déterminer si le trafic et/ou la formation d’oligomères du HLA-B27 étaient corrélés à sa surexpression. Pour cela, notre équipe a développé des protéines de fusion (HLA-BYFP et HLA-BRLuc) ainsi que la technique BRET afin d’étudier les interactions HLA-B/HLA-B. Au moyen de ce système expérimental, nous avons montré la formation de vésicules intracellulaires riches en protéines HLA-B mal repliées lorsqu’elles étaient fortement exprimées, qu'il s'agisse d'allèles associés à la SA (HLA-B*2702, -05, et -07) ou non (HLA-B*2706, et -09, HLA-B*0702). Cependant, ce phénomène était significativement plus prononcé pour les sous-types associés à la SA. Dans les conditions de forte expression, nous avons également observé que les sous-types associés à la SA formaient des oligomères qui se comportent différemment de ceux formés par la protéine HLA-B7. Ce phénomène ne semble pas être dû au déclenchement de la réponse cellulaire « Unfolded Protein Response » (UPR) et n’est pas abrogé par l’inhibition du protéasome. / Ankylosing spondylitis (AS), the most common form of spondyloarthritis (SpA), is strongly associated with the MHC class I HLA-B27 molecule. Although this association has been largely studied, mechanisms of pathology remain unclear. Development of a spontaneous inflammatory disease resembling human SpA in HLA-B27 transgenic rats confirmed the direct involvement of HLA-B27 and allowed to associate disease development with high expression levels of this molecule. Moreover, the HLA-B27 protein has an enhanced propensity to misfold and form aberrant disulfide linked heavy chain oligomers in the endoplasmic reticulum and at the cell surface. The goal of my thesis work was to determine if the HLA-B27 traffic and/or its ability to form oligomers are involved in this requirement of overexpression. For that, our team has developed fusion proteins ((HLA-BYFP and HLA-BRLuc) and the BRET technique to study, in vitro, the HLA-B/HLA-B interactions. Using this experimental system, we have shown the formation of intracellular vesicles, in which misfolded/unfolded HLA-B proteins accumulated when they were highly expressed, for both AS-associated alleles (HLA-B*2702, -05, et -07) or not (HLA-B*2706, et -09, HLA-B*0702). This phenomenon is strongly pronounced for AS-associated subtypes. For high-level expression, we also observed that the AS-associated subtypes form oligomers that behave differently from those formed by the HLA-B7 control protein. This phenomenon doesn’t appear to be due to unfolded protein response (UPR) triggering and is not abrogated by proteasome inhibition.
5

The Role of Endoplasmic Reticulum Aminopeptidase 1 (ERAP1) in the Pathogenesis of Ankylosing Spondylitis

Haroon, Nigil 12 December 2012 (has links)
Ankylosing spondylitis (AS) is associated with HLA-B*2704 and B*2705 but not with HLA-B*2706 and B*2709. Genome wide studies recently identified ERAP1 as an important genetic association in AS and could be the missing link in the pathogenesis of AS. I studied the implications of the two known actions of ERAP1 on AS pathogenesis. For assessing the peptide trimming function, surface HLA-B27 and MHC-I free heavy chain (FHC) expression on peripheral blood mononuclear cells of AS patients were studied. Subsequently, in an in vitro system of C1R cells expressing different AS-associated and AS-neutral HLA-B27 subtypes, I studied the effect of ERAP1 suppression on HLA-B27 and FHC expression. To assess the cytokine receptor shedding function, I studied serum cytokine receptor level variation with ERAP1 polymorphisms and its relationship to disease activity in AS patients. Finally, I studied the effect of variants of ERAP1 and other members of the antigen presentation machinery on radiographic severity in AS patients. AS patients with the major allele of the ERAP1 rs27044 polymorphism had higher FHC expression on monocytes. In C1R cells ERAP1 suppression led to an increase in intracellular FHC (IC-FHC) and B27-peptide complexes identified by a special MARB4 antibody, but only in C1R cells expressing the AS-associated subtypes HLA-B*2704 and B*2705. ERAP1 variants had no effect on serum cytokine receptor levels. Baseline radiographic severity was associated with ERAP1 polymorphism in univariate analysis only. LMP2 variants were associated with baseline radiographic severity in multivariate analysis. ERAP1 affects peptide presentation and FHC formation by HLA-B27 and could be the missing link in the pathogenesis of AS. ERAP1 through its differential HLA-B27 subtype interaction could explain why certain subtypes of HLA-B27 are associated with AS while others are not. Larger studies are required to look closely at the effect of ERAP1 on radiographic severity and progression in AS.
6

The Role of Endoplasmic Reticulum Aminopeptidase 1 (ERAP1) in the Pathogenesis of Ankylosing Spondylitis

Haroon, Nigil 12 December 2012 (has links)
Ankylosing spondylitis (AS) is associated with HLA-B*2704 and B*2705 but not with HLA-B*2706 and B*2709. Genome wide studies recently identified ERAP1 as an important genetic association in AS and could be the missing link in the pathogenesis of AS. I studied the implications of the two known actions of ERAP1 on AS pathogenesis. For assessing the peptide trimming function, surface HLA-B27 and MHC-I free heavy chain (FHC) expression on peripheral blood mononuclear cells of AS patients were studied. Subsequently, in an in vitro system of C1R cells expressing different AS-associated and AS-neutral HLA-B27 subtypes, I studied the effect of ERAP1 suppression on HLA-B27 and FHC expression. To assess the cytokine receptor shedding function, I studied serum cytokine receptor level variation with ERAP1 polymorphisms and its relationship to disease activity in AS patients. Finally, I studied the effect of variants of ERAP1 and other members of the antigen presentation machinery on radiographic severity in AS patients. AS patients with the major allele of the ERAP1 rs27044 polymorphism had higher FHC expression on monocytes. In C1R cells ERAP1 suppression led to an increase in intracellular FHC (IC-FHC) and B27-peptide complexes identified by a special MARB4 antibody, but only in C1R cells expressing the AS-associated subtypes HLA-B*2704 and B*2705. ERAP1 variants had no effect on serum cytokine receptor levels. Baseline radiographic severity was associated with ERAP1 polymorphism in univariate analysis only. LMP2 variants were associated with baseline radiographic severity in multivariate analysis. ERAP1 affects peptide presentation and FHC formation by HLA-B27 and could be the missing link in the pathogenesis of AS. ERAP1 through its differential HLA-B27 subtype interaction could explain why certain subtypes of HLA-B27 are associated with AS while others are not. Larger studies are required to look closely at the effect of ERAP1 on radiographic severity and progression in AS.
7

The role of HLA-B27 in inflammatory arthritis

Lynch, Sarah Janice January 2009 (has links)
The MHC class I allele, HLA-B27, is strongly associated with a group of inflammatory arthritic conditions collectively known as spondyloarthropathies (SpA). Ankylosing spondylitis (AS) shows the strongest association with 90-95 % of patients being HLA-B27 positive. The relationship between HLA-B27 and SpA has been known for over 30 years, however despite ongoing research, the reason for this association has not yet been elucidated. In more recent years, research has focused on intrinsic properties of the HLA-B27 allele, in particular its propensity to misfold, forming homodimers. It has been proposed that these homodimers could be associated with the disease process through the activation of an ER stress response known as the unfolded protein response (UPR), or through aberrant recognition at the cell surface. We have investigated whether the expression of HLA-B27 is associated with the activation of the UPR. We have studied the expression of BiP, and the cleavage of XBP1 and ATF6 using stable and transiently expressing cell lines. We have also investigated the formation of non-B27 homodimers using a human cell line stably expressing HLA-B8, and finally we have studied the expression of homodimers in exosomes, small immunomodulatory vesicles released from numerous cell types. The results presented here lead us to conclude that in vitro studies of the UPR are complicated, prone to a number of technical issues, and may therefore not be appropriate for gaining information that would be of significant use when comparing to the real disease scenario. Our data suggest that non-B27 dimers may be strongly influenced by both the overexpression of MHC class I heavy chains and also the redox environment within the cell. We have isolated a novel fully folded, beta-2m-associated, MHC class I homodimer in exosomes and have detected a novel HLA-A and HLA-B mixed heavy chain dimer. Our results suggest that these dimers form through interactions between the cysteine residues in the cytoplasmic tail and that these dimers form in exosomes because they contain lower levels of the important antioxidant glutathione when compared to whole cells. Together, these results define a new MHC class I structure present on exosomes at significant levels, which could potentially influence immune recognition by both antigen-specific T cell receptors and NK family receptors. The data also poses questions about whether these novel structures, when they involve HLA-B27, could influence the pathogenesis of spondyloarthropathies.
8

La drosophile transgénique HLA-B27 : un nouveau modèle pour l'étude des spondyloarthrites / The transgenic Drosophila HLA-B27 : a new model for the study of spondyloarthritis

Grandon, Benjamin 15 October 2018 (has links)
Les spondyloarthrites (SpA) sont des maladies inflammatoires chroniques articulaires qui se caractérisent par des atteintes de la colonne vertébrale et des articulations périphériques, en particulier des enthèses, souvent associées à des manifestations extra-articulaires telles que le psoriasis, l’uvéite, ou l’inflammation intestinale. Ces maladies complexes possèdent une forte composante génétique dominée par l'antigène HLA-B27 du complexe majeur d'histocompatibilité de classe I (CMH-I), présent chez plus de 80% des patients atteints de SpA. Découverte il y a 45 ans, l'association entre HLA-B27 et le développement des SpA reste inexpliquée. Plusieurs hypothèses ont été proposées pour expliquer cette association au niveau moléculaire. Cependant, la plupart se heurtent à des incohérences expérimentales qui semblent les invalider. Pour élucider les mécanismes moléculaires pathogènes liés au HLA-B27, nous avons utilisé une nouvelle approche. Drosophila melanogaster est un puissant modèle génétique qui a permis des avancées considérables dans la compréhension de nombreuses fonctions des cellules de métazoaires, ainsi que dans la description des processus cellulaires et moléculaires de nombreuses pathologies humaines. Nous avons établi plusieurs lignées de drosophiles transgéniques pour des formes d’HLA-B associées aux SpA ou pour une forme non associée à la maladie, ainsi que pour la chaîne invariante du CMH-I, la β2m humaine (hβ2m). L'expression des formes associées à la maladie, exclusivement en présence de la hβ2m, dans l'aile et dans l'œil de la drosophile conduit à l'apparition de deux phénotypes spécifiques. Mes résultats ont permis de mettre en évidence que le phénotype de perte des veines transversales de l’aile était associé à une perturbation de la signalisation par la voie des Bone Morphogenetic Protein (BMP). Cette perturbation est associée à une co-localisation de HLA-B27 avec le récepteur BMP de type I, Sax. Nos résultats préliminaires obtenus dans les cellules de patients atteints de SpA suggèrent l’existence d’une co-localisation analogue d’HLA-B27 avec le récepteur ALK2, orthologue de Sax. L'ensemble de nos résultats plaide en faveur d’un rôle pathogène de HLA-B27 passant par une dérégulation de la voie BMP à l’intersection des voies de l’ossification et de l’inflammation et pourrait donc s’appliquer à la physiopathologie des SpA. / Spondyloarthritis (SpA) is a chronic inflammatory rheumatic disorder characterized by joint manifestations affecting the spine, peripheral joints and entheses, as well as extra-articular manifestations such as psoriasis, uveitis, or intestinal inflammation. This complex disorder has a strong genetic component dominated by the HLA-B27 antigen of the major histocompatibility complex class I (MHC-I), which is present in more than 80% of SpA patients. Discovered 45 years ago, the association between HLA-B27 and SpA development remains unexplained. Several hypotheses have been proposed to explain this association at the molecular level, but all face experimental inconsistencies that seem to invalidate them. Therefore, it appeared to us essential to elaborate new and yet unexplored approaches in order to better understand the molecular role of HLA-B27 in SpA development. Drosophila melanogaster is a powerful genetic model that has led to considerable advances in understanding numerous functions of metazoan cells, as well as in describing the cellular and molecular processes of many human pathologies. To elucidate the molecular pathogenic mechanisms associated with HLA-B27, we have established several transgenic Drosophila lines for SpA-associated and non-associated of HLA-B alleles, as well as for the MHC-I invariant chain, the human 2-microglobulin (hβ2m). Expression of the HLA-B27 alleles, in the presence of hβ2m, in the Drosophila wing and eye led to two specific phenotypes. The crossveinless wing phenotype is due to a disturbance in the Bone Morphogenetic Protein (BMP) signaling pathway. Interestingly, this misregulation is associated with a co-localization of HLA-B27 and the BMP type I receptor named Sax. Our preliminary results obtained in SpA patient cells suggest that HLA-B27 also colocalizes with ALK2 receptor, which is ortholog to Sax. Altogether, our results suggest that the pathogenic role of HLA-B27 in SpA may depend on a BMP signaling misregulation at the crosstalk between ossification and inflammation.
9

Jämförelse och utvärdering av FastQ B*27 direct och LAMP Human HLA-B27 direct detection KIT för HLA-B27 allel detektion : Två kit utvärderas mot nuvarande metod på Länssjukhuset Ryhov för utbyte av rutindiagnostik / Comparison and evaluation of FastQ B*27 direct and LAMP Human HLA-B27 direct detection KIT for HLA-B27 allele detection

Sollerbrant, Hanna, Suleiman, Joude January 2024 (has links)
Autoimmunitet är ett tillstånd där kroppens immunsystem felaktigt attackerar och skadar sina egna vävnader och celler. HLA-B27 är en genvariation som kan kopplas till autoimmun sjukdom som ankyloserande spondylit med en prevalens på 2-4% i världens befolkning. Denna studie syftade till att utvärdera och jämföra två kit för HLA-B27 alleler mot den nuvarande metoden på Länssjukhuset Ryhov i Region Jönköpings län. De metodprinciper som användes var realtids-PCR samt LAMP.  Totalt analyserades 37 avidentifierade blodprover med vardera av kiten samt med nuvarande metod. Resultatet visade en överensstämmelse med avseende på förväntade positiva och negativa resultat för HLA-B27 för de två kiten jämfört med nuvarande metoden. De tre metoderna/kiten detekterar de vanligaste HLA-B27 allelerna. Utifrån studiens resultat visade sig båda kiten vara effektiva, lättanvända samt ha stabila reagenser. Dessutom uppnådde båda kiten de IVD-krav som ställs inom EU. / Autoimmunity is a condition where the body's immune system mistakenly attacks and damages its own tissues and cells. HLA-B27 is a genetic variation that can be linked to autoimmune diseases such as ankylosing spondylitis, with a prevalence of 2-4% in the world’s population. This study aimed to evaluate and compare two kits for HLA-B27 alleles against the current method at Ryhov County Hospital in Region Jönköping County. The methodological principles used were real-time PCR and LAMP. A total of 37 anonymized blood samples were analyzed using each of the kits and the routine method. The results showed concordance with the expected positive and negative results for HLA-B27 between the two kits compared to the current method. The three methods/kits detect the most common HLA-B27 alleles.  Based on the study’s results, both kits proved to be effective, user friendly, and have stable reagents. Additionally, both kits met the IVD requirements set within the EU.
10

The rechargeable lithium/air battery and the application of mesoporous Fe₂O₃ in conventional lithium battery

Bao, Jianli January 2009 (has links)
By replacing the intercalation electrode with a porous electrode and allowing lithium to react directly with O₂ from the air, the new rechargeable Li/O₂ battery system was studied. The porous cathode is comprised of carbon, catalyst and binder. The effect of every component was investigated. The catalyst was believed to play an important role in the performance of the electrode. A number of potential materials have been examined as the catalyst for the O₂ electrode. It suggests that the nature of the catalyst is a key factor controlling the performance of the O₂ electrode. Several catalysts based on first row transition metal oxides each with three different morphologies, bulk, nanoparticulate and mesoporous were studied. The influence of the morphology on the discharge and charge voltage, discharge capacity and cyclability were examined. Among all the catalysts studied, α-MnO₂ nanowires was found to be the best candidate. The reversible capacities of 3000 mAhg⁻¹(normalised by the mass of carbon) or 505 mAhg⁻¹ (based on the total mass of cathode + O₂ ) was obtained. Some of other factors, such as type of carbon, type of binder, type of electrolyte, the construction of cathode and the modification of the catalyst were also investigated, even just in the early stage. Capacity fading during cycling is the main problem in all the cases. A number of experiments were carried out to understand and attempt to avoid the fading problem. After successful synthesis of mesoporous α-Fe₂O₃ with unique properties (by Jiao et al.), the application of these materials in conventional Li battery was studied. Mesoporous α-Fe₂O₃ with ordered walls, mesoporous α-Fe₂O₃ with disordered walls and Fe₂O₃ nanoparticles were examined. It was also applied to examine the different factors that influence the rate of conversion electrodes, i.e., Li⁺ and e⁻ transport to and within the particles, as well as the rate of the two-phase reaction, demonstrating that for this conversion reaction electron transport to and within the particles is paramount.

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