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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.
171

The humoral immune response to streptococcal cell wall-induced arthritis in the rat.

Effertz, Bernard Stephen. January 1989 (has links)
I investigated the humoral immune response to streptococcal cell walls (SCW) in arthritis susceptible Lewis and resistant Fisher rats. All rats were given a single intraperitoneal injection of either SCW or saline (controls). Rats were sacrificed, three rats per time point, over an eleven week period and serum was collected for ELISA. SCW injected Lewis rats produced anti-SCW antibody, whereas control rats did not. Anti-SCW antibody was significantly elevated over controls between days 14-28 (post injection). Both saline and SCW injected Fisher rats produced anti-SCW antibody, but with different kinetics. Anti-SCW antibody increased by day 7 and remained elevated over controls till day 21, after which there was no difference. ELISA were designed to determine the SCW epitope(s) recognized by anti-SCW antibody. Formamide extracts of SCW, peptidoglycan and polysaccharide, were investigated along with the terminal epitope of polysaccharide, N-acetyl-D-glucosamine, and the peptidoglycan precursor peptide. The data revealed that anti-SCW antibody was directed against a combined SCW epitope, given the lack of significant binding to any of the SCW epitopes tested. Isotype analysis of anti-SCW antibody revealed that the Lewis response was composed primarily of IgG2a whereas the Fisher response was composed primarily of IgM. Binding of rat IgG isotypes to whole streptococcus, SCW, peptidoglycan, and polysaccharide was investigated, given the possibility of background binding by the streptococcal Fc-receptor. Streptococcal binding of rat IgG was specific for IgG2c and the polysaccharide portion of SCW was necessary for binding. Passive immunization of naive Lewis rats with antibody from rats with active arthritis was ineffective at transferring the disease. However, subcutaneous injection of affinity purified anti-SCW antibody or IgG into Lewis rats, followed twenty-four hours later by a single intraperitoneal injection of SCW, suppressed the acute phase and inhibited the chronic disease. IgM rheumatoid factor (RF) was present in the serum of both saline and SCW injected Lewis and Fisher rats. However, SCW injection only induced a significant increase in IgM RF (between days 3-7) in Lewis rats. Passive immunization of Fisher rats with affinity purified IgM RF (from Lewis serum), three days post SCW injection, was ineffective at inducing arthritis.
172

Effects of Resistance Training on Insulin Sensitivity and Markers of Inflammation in Rheumatoid Arthritis Patients Treated with Remicade

Gates, Donald L. January 2009 (has links)
INTRODUCTION Rheumatoid arthritis (RA) is a disease of chronic inflammation in the joints and organs. RA patients exhibit 4-fold increased incidence of CVD, increased prevalence of insulin resistance (IR) and increased mortality. Aerobic and resistance training (RT) programs have been suggested for the management of RA symptoms and reduction of comorbidities, including insulin resistance. Exercise has been shown by recent evidence to be safe and beneficial in RA patients. RT has been documented to improve inflammation and insulin sensitivity. The present study was undertaken to examine the impact of a sixteen week intensive training regimen on disease status, body composition, markers of inflammation and indicators of insulin resistance in RA patients undergoing infliximab therapy, a potent RA treatment.METHODS30 RA patients were randomized into exercise (EX) or control (C) groups. EX patients underwent a 16-week supervised, intensive, progressive and individualized resistance training regimen. Participants were monitored by professional fitness trainers during all exercise sessions. Subjects were assessed prior to and after intervention. Assessments included disease status, strength and functional testing, anthropometrical and body composition analysis, analysis of markers of inflammation and assessment of insulin sensitivity.RESULTS EX subjects significantly increased in strength and functional ability without worsening of disease state, and increased lean mass from baseline. Fat mass was significantly reduced in EX. Glucose and resistin levels increased significantly following EX intervention. Mean IR was unchanged, but EX subjects with elevated IR did show improvement following training. Regression analysis indicates duration of infliximab therapy to be correlated with improved insulin sensitivity.CONCLUSIONS RA patients taking infliximab tolerated an intensive resistance training program. Participants increased strength and lean mass while decreasing fat mass and displayed improved functional capacity. Disease status was not worsened by the regimen. Though the mean measure of IR did not improve, those patients with the most adverse scores did show improvement following the intervention. Furthermore, regression analysis indicates that infliximab treatment duration was linked to reduced IR. In conclusion, resistance training improved strength and functional ability in RA patients taking infliximab without disease degradation, and may help reduce IR in those patients with elevated resistance.
173

Exploring the perceptions of women with rheumatoid arthritis of how their illness impacts their relationship with their intimate partner.

Gerber, Roné January 2006 (has links)
<p>This study explored women's perceptions of how their illness (Rheumatoid Arthritis- RA) affects their relationship with their intimate life partner. RA is a chronic, inflammatory, auto-immune illnes, which mainly affects the synovial membranes of multiple joints. This highly inflammatory poly-arthritis may lead to joint destruction, chronic pain, deformity and loss of functioning as unfortunate outcomes of the established illness. RA affects key life domains such as psychological well-being, social well-being, family and couple relationships, employment, loss of independence and restrictions in daily functioning.</p>
174

The role of anti-collagen type II antibodies in the pathogenesis and prognosis of rheumatoid arthritis

Manivel, Vivek Anand January 2017 (has links)
Rheumatoid arthritis (RA) which affects 0.5-1% of the world population and is characterised by joint erosions and presence of the autoantibodies anti-citrullinated protein antibodies (ACPA) and rheumatoid factor. Collagen II (CII) is a joint-specific antigen and we have shown that antibodies against CII (anti-CII) are present in around 8% of RA patients. RA patients with anti-CII are characterized by acute RA onset with elevated CRP and early joint erosions at the time of RA onset. Polymorphonuclear granulocytes (PMN) and peripheral blood mononuclear cells (PBMC) are abundant in RA synovial fluids, where they can interact with anti-CII, thus forming immune complexes (IC) with CII. In my thesis I have shown that PMN upregulated the cell surface markers CD66b and CD11b and downregulated CD16 and CD32 after stimulation with anti-CII IC. These changes in CD66b and CD16 associated to joint erosions to a larger extent than did PBMC responses to anti-CII IC. PMN cocultured with PBMC and stimulated with anti-CII IC showed augmented chemokine production that was dependent on TLR4 and functionally active PMN enzymes. This mechanism can lead to accumulation of inflammatory cells in joints of RA patients who are anti-CII positive around the time of RA diagnosis, and may thus help explain the acute onset RA phenotype associated with anti-CII. In a large Swedish RA cohort, anti-CII associated with elevations in clinical and laboratory measures of disease activity at diagnosis and until 6 months, whereas ACPA associated with late inflammation. Anti-CII seropositive RA was associated with improvements in clinical measurements and was negatively associated with smoking in contrast to ACPA that was associated with worseneing of clinical symptoms and associated positively with smoking. Anti-CII levels associated to  HLADRB1*03 and  HLADRB1*01 whereas ACPA showed negative association to HLA-DRB1*03. In a Malaysian RA cohort anti-CII also associated to elevated CRP at the time of diagnosis. Anti-CII seropositive RA represents a distinct phenotype, in many respects representing the converse  to the clinical, genetic and smoking associations described for ACPA. Early determinations of anti-CII in parallel to ACPA predict the inflammatory outcome in RA.
175

Homöostatische Mechanismen der CD4+ T-Zellgenese bei Rheumatoider Arthritis

Schatz, Annika Katrin 12 December 2016 (has links) (PDF)
Die Rheumatoide Arthritis ist eine Autoimmunerkrankung, die mit grundlegenden Veränderungen im CD4+ T-Zellpool einhergeht. Viele Studien konnten zeigen, dass die Gruppe der T-Helferzellen bei erkrankten Personen vermehrt Anzeichen von replikativer Seneszenz und das adaptive Immunsystem deutliche Zeichen der Immunoseneszenz aufweisen. Als zum Teil ursächlich hierfür konnte ein reduzierter Thymusoutput festgestellt werden. Das Ziel der vorliegenden Studie war es, aufbauend auf Erkenntnissen von Six und Kollegen anhand einer Lymphozytenvorläuferzelle, die im peripheren Blut zirkuliert, in vivo in der Lage ist, den Thymus zu besiedeln und sich in reife T-Zellen zu entwickeln, den Thymusinput abzuschätzen, um eine defiziente Thymusbesiedlung als eventuelle Ursache des reduzierten Thymusoutput festzustellen. Hierzu wurde das Blut von 28 Patienten mit Rheumatoider Arthritis und altersentsprechenden gesunden Kontrollen mittels Durchflusszytometrie auf mehrere relevante reife T-Helferzellpopulationen, naive CD4+ T-Zellen und benannte lymphozytäre Vorläuferzelle untersucht. Es konnten dann direkte Vergleiche des prozentualen Anteils bestimmter T-Helferzellgruppen zwischen Erkrankten und Gesunden gezogen sowie Korrelationen verschiedener Zellgruppen untereinander hergestellt werden. Die gewonnenen Ergebnisse wurden mit der hierzu vorliegenden Literatur verglichen und diskutiert.
176

A Retrospective Study Determining the Efficacy of Etanercept Treatment in Juvenile Rheumatoid Arthritis Patients in a Small Clinic Setting

Cox, Rosalie January 2006 (has links)
Class of 2006 Abstract / Objectives: To determine the effectiveness of etanercept therapy on C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), height, weight and body mass index (BMI) of patients with juvenile rheumatoid arthritis in an ambulatory pediatric clinic. Methods: This project used a pretest-posttest design that assessed patients before treatment with etanercept and then 6 months after the treatment was begun. Pre-treatment and post-treatment data were obtained through a retrospective chart review. A chart review was performed to collect each patient’s ESR, CRP, height, weight, BMI, and demographic data using a standardized data collection instrument. A paired t-test was performed to compare the pre-treatment and post-treatment data for the ESR, CRP, height, weight and BMI measurements. Results: Nine patients were identified that met the study inclusion. The mean age (SD) of the patients was 13.1 (4.4) years. Increases in weight and height parameters were seen after 6 months of etanercept treatment (p= 0.05, 0.002, respectively). There were no differences found in BMI, CRP and ESR parameters (p= 0.133, 0.753, 0.188, respectively) between the pre and post measurements. Conclusions: This pre-post analysis of 9 patients with juvenile rheumatoid arthritis found that etanercept therapy was associated with a significant gain in weight and height. However, this study found no differences in CRP or ESR after etanercept treatment. Additional research in larger populations is needed to more fully describe the changes in monitoring parameters following etanercept therapy.
177

A2B adenosine receptor modulation of TNF-alpha expression in mouse rheumatoid arthritis

Ciocca, Caroline 12 July 2017 (has links)
Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that leads to destruction of articular cartilage and subchondral bone at the synovial joints. Clinically, RA is characterized by swelling, tenderness and destruction of synovial joints, which results in severe disability and premature mortality. In the RA disease state, inflammation in the synovial compartment is regulated by a complex cytokine and chemokine network, including tumor necrosis factor α (TNFα), which has been clinically demonstrated a key mediator of RA pathogenesis. TNFα can be found in elevated levels in the synovial fluid and serum of RA patients and the role of the cytokine in both the inflammation and bone destruction of RA suggests it is important in the understanding of disease progression as well as the development of therapeutic targets. Many of the biological processes that mediate RA, including bone turnover and cartilage resorption, involve signaling pathways that are mediated by adenosine and its receptors. The A2B adenosine receptor (A2BAR) is highly expressed in the synoviocytes of RA patients and the receptor has a similar expression profile in humans and mice. The goal of this thesis was to use a mouse model of RA to understand how the A2B adenosine receptor modulates TNFα and other destructive enzymes that contribute to the progression of the disease. A collagen antibody-induced arthritis (CAIA) mouse model was used to determine the effect of A2BAR ablation on systemic and joint-specific TNFα expression. Comparable arthritic conditions were observed in CAIA mice of both A2BAR knockout (KO) and wild-type (WT) genotypes and the absence of the A2BAR gene did not result in any observable differences in the gross arthritic state created in each genotype. Immunohistochemistry analysis of TNFα expression in mouse paws revealed that paw joints from CAIA A2BAR KO mice exhibited more robust TNFα staining compared to CAIA WT specimens of the same treatment duration. ELISA analysis of the serum showed that only CAIA A2BAR KO mice had greater serum production of TNFα at day 10 after induction of arthritis. TNFα and matrix metalloproteinase-9 mRNA expression were also elevated in KO CAIA knee joints in comparison to WT CAIA knee joints; however, WT CAIA mice were found to have higher levels of aggrecanase mRNA compared to KO mice. These results suggest that while the loss of A2BAR activity leads to a hyper-inflammatory state, the A2B adenosine receptor alone is not responsible for the progressive inflammation of the synovial joints associated with rheumatoid arthritis.
178

Cinética plasmática da lipoproteína de baixa densidade e avaliação dos aspectos qualitativos da lipoproteína de alta densidade em indivíduos com artrite reumatóide / Plasma kinetics of an LDL-like non-protein nanoemulsion and transfer of lipids to high-density Lipoprotein (HDL) in patients with rheumatoid arthritis

Pozzi, Fernanda Santos 10 February 2012 (has links)
Artrite reumatóide é uma doença auto-imune que apresenta acentuado quadro inflamatório e proliferação celular o que, provavelmente, determina a alta prevalência de doenças cardiovasculares quando comparados a população mundial. A mortalidade e a morbidade conseqüentes das doenças cardiovasculares estão 2 vezes aumentadas em pacientes com artrite reumatóide e um dos principais fatores de risco relacionados ao desenvolvimento da aterosclerose é a dislipidemia. Esse importante fator de risco vem sendo associado à artrite reumatóide e as concentrações plasmáticas de lípides são constantemente avaliadas, já que se encontra bem estabelecido a relação entre dislipidemia e alta incidência de doença cardiovascular. No entanto, o verdadeiro impacto das alterações lipídicas na artrite reumatóide não é bem conhecido, já que os resultados de perfil lipídico são contraditórios. Alterações nas concentrações plasmáticas de lípides não necessariamente acompanham distúrbios no metabolismo das lipoproteínas plasmáticas. O objetivo do presente estudo foi avaliar aspectos do metabolismo da LDL e da HDL, em pacientes com artrite reumatóide. Nesse sentido, foi avaliada a cinética plasmática de uma nanoemulsão lipídica artificial com comportamento metabólico semelhante ao da LDL em 30 pacientes com artrite reumatóide divididos em 2 grupos de acordo com a atividade da doença, alta atividade (n=14) e remissão (n=16) e 30 indivíduos controle. A nanoemulsão marcada com éster de colesterol 14EC (EC-14C) e colesterol livre 3H (CL-3H) foi injetada endovenosamente após 12 horas de jejum. As amostras de sangue foram coletadas em tempos pré-determinados (5 min, 1, 2, 4, 6, 8 e 24 horas) após a injeção, para determinação das curvas de decaimento plasmático e da taxa fracional de remoção (TFR) dos lípides marcados, por análise compartimental. As TFR-EC-14C e TFR-CL-3H foram maiores no grupo AR quando comparado ao grupo controle (49%, p<0,05 e 44%, p<0,05, respectivamente), não havendo diferença entre os subgrupos de artrite reumatóide. No grupo artrite reumatóide e em seus subgrupos, as concentrações de HDL-C e apo E foram maiores quando comparados ao grupo controle (33%, p<0,0001 e 20%, p<0,01, respectivamente), enquanto os níveis de apo B foram menores na artrite reumatóide quando comparados ao grupo controle (16%, p<0,05). A transferência de colesterol esterificado radioativo da nanoemulsão para a HDL foi menor na artrite reumatóide, comparando-se com o grupo controle. A transferência dos outros lípides foi similar nos dois grupos. A HDL dos pacientes com artrite reumatóide foi menor do que a dos controles. Esses resultados podem contribuir com a melhor compreensão de possíveis mecanismos relacionados a uma maior incidência de doenças cardiovasculares em pacientes com artrite reumatóide / Mortality and morbidity, as a consequence of cardiovascular diseases, is twice as high in patients with rheumatoid arthritis than in the general worldwide population. This autoimmune disease has predominant inflammatory and cell proliferation background probably explains the high prevalence of cardiovascular disease. Dyslipidemias are important risk factors for cardiovascular disease. This study investigated the link between RA and plasma lipids as a predisposition to this high cardiovascular disease incidence. However, the impact of lipids on cardiovascular risk in rheumatoid arthritis is unclear. So much so, that lipid profiles in patients with rheumatoid arthritis in published studies is contradictory. The events of intravascular lipoprotein metabolism do not necessarily produce altered levels of plasma lipids. In an attempt to unravel novel dysfunctional mechanisms that could trigger pro-atherogenic processes beyond the concentration of the plasma lipids, plasma clearance of a lipidic nanoemulsion that resembles the LDL metabolic behavior were investigated in rheumatoid arthritis patients and compared to control subjects without the disease. 30 patients with rheumatoid arthritis divided into 2 groups according to disease activity, high activity (n=14) and remission (n=16), and 30 controls were studied. A nanoemulsion labeled with 14C-cholesteryl esther (14C-CE) and 3H-free cholesterol (3H-FC) were endovenously injected after which blood samples were collected at pre-determined periods (5 min, 1, 2, 4, 6, 8 and 24 hours), in order to determine the radioactivity of the plasma decay curves and calculate the fractional clearance rate (FCR) of the labeled lipids for compartmental analysis. In the rheumatoid arthritis group and subgroups the HDL-C and apo E concentration were higher when compared to control group (33%, p<0,0001 e 20%, p<0,01, respectively) while apo B concentration was lower (16%, p<0,05). The 14-CE-FCR and 3H-FC-FCR were greater in rheumatoid arthritis group and subgroups when compared to controls (49%, p<0,05 e 44%, p<0,05, respectively). There were no differences between the rheumatoid arthritis subgroups. Therefore, rheumatoid arthritis accelerates the LDL plasma removal, as indicated by a higher 14-CE-FCR and 3H-FC-FCR. The transfer of other lipids was also similar in both groups. The HDL of the rheumatoid arthritis patients was lower than that of the control group. These results could clarify possible mechanisms that can be related to a higher cardiovascular incidence in patients with rheumatoid arthritis
179

Mechanism of bone loss in rheumatic diseases

Hauser, Barbara January 2016 (has links)
Osteoporosis and fragility fractures are recognized complications of inflammatory rheumatic diseases. This is thought to result from the effects of chronic inflammation, relative immobility and corticosteroid use. A rare syndrome of osteoporosis in a patient with coeliac disease has been described which results from production of neutralizing antibodies to the bone protective protein osteoprotegerin (OPG). The aim of my thesis is to evaluate prevalence and clinical predictors of osteoporosis in a contemporary cohort of patients with rheumatoid arthritis (RA) and to investigate the role of OPG autoantibodies in the pathogenesis of osteoporosis in rheumatic diseases. In a retrospective cohort study, I found that the overall prevalence of osteoporosis in patients with RA was 29.9% which is in keeping with older reports that recorded a prevalence rate between 17% and 36%. In our contemporary cohort osteoporosis was significantly more common than in a gender and age matched control cohort (17.4%). Further analysis showed that only age and BMI were independent predictors of osteoporosis in RA. A predictive tool based on age and BMI was developed which had 91.4% sensitivity for the detection of osteoporosis in an independent RA population. I went on to screen for the presence of autoantibodies to OPG in patients with various rheumatic diseases. In a study of 75 patients with rheumatoid arthritis and 199 healthy controls OPG autoantibodies were detected in two controls (1%) compared with seven patients with RA (9.3%). The RA patients with detectable OPG antibodies had a longer disease duration, higher DAS28 scores and higher levels of the bone resorption marker CTX than RA patients who did not have autoantibodies. Purified IgG from patients with high levels of OPG antibodies blocked the ability of recombinant OPG to inhibit RANKL induced NFκB activation in a HEK293 cell based assay indicating that they were functional. In a further study of 134 patients with ankylosing spondylitis (AS), 16 patients (11.9%) had detectable OPG antibodies. The presence of OPG-Ab was independently associated with reduced hip bone mineral density and an increased risk of fractures in this population. In patients with a longer disease duration we have also observed that there was a higher discrepancy between spinal and hip BMD in OPG-Ab positive patients compared with OPG ab negative patients (p=0.003). In order to investigate if OPG antibodies affected measurement of serum RANKL concentrations as detected by ELISA using OPG as the capture reagent, I measured OPG ab and free RANKL concentrations in 55 rheumatic disease patients. Surprisingly there was a significant positive correlation between free RANKL and OPG Ab concentrations (r=0.430, p=0.001) which was the opposite to what I had expected. These findings reject the hypothesis that OPG ab block binding of synthetic OPG to RANKL in the ELISA. In conclusion, I have shown that osteoporosis is a common complication in RA and I have developed a new risk prediction tool for the use in clinical practice. I have also found that OPG antibodies are produced more commonly in patients with RA and AS than in healthy controls and that antibody levels correlate with bone resorption markers in RA and bone mineral density in AS patients. In vitro studies have shown that some OPG antibodies have functional effects on RANKL signalling. These findings raise the possibility that OPG antibodies may contribute to the pathogenesis of local and systemic bone loss in rheumatic diseases and signal the need to study the relationship between these antibodies and bone disease in large-scale longitudinal studies.
180

The clinical and immunological significance of ectopic lymphoneogenesis in the rheumatoid synovial membrane

Humby, Frances Claire January 2010 (has links)
Despite the development of new biomarkers predicting prognosis in rheumatoid arthritis (RA) remains challenging and targeting of powerful biologics difficult. The presence of ectopic germinal centres (GC) within synovium has long been recognised (ectopic lymphoneogenesis [ELN]) and data have suggested that they manufacture antibody (Ab). High affinity class switched Ab production occurs through class switch recombination (CSR) and somatic hypermutation (SHM) both critically dependent on activation induced cytidine deaminase (AID). However, whether ectopic GCs express AID has not been known. Nonetheless data associating ELN with disease severity suggest a role for ELN in RA pathogenesis and as a potential biomarker. A classification system for RA synovium, based on the concept of ELN has been proposed as: (i) aggregate, (ii) aggregate GC+ and, (iii) an unorganised infiltrate. However whether these distinct pathotypes and/or degree of aggregation equate to disease severity is unclear. Thus my first aim was to develop and validate a pathological scoring system for rheumatoid synovium capable of quantifying the degree of ELN. My second aim was to investigate whether the presence and/or degree of ELN within the synovial membrane correlated with both clinical phenotype and predicted erosive damage. I demonstrate that the aggregational score developed is highly reliable and that ELN within synovial tissue associates with a higher level of synovial inflammation but is not predictive of damage. My third aim was to investigate whether GCs within RA synovium were functional. I provide evidence of functionality by demonstrating that ectopic GCs invariably express AID, are surrounded by anti-CCP+ plasma cells, support ongoing CSR and the manufacture of anti-CCP Abs. My final aim was to characterise a cohort of synovial B cells consistently found surrounding ectopic GCs. I identify a novel B cell subset within RA synovium, interfollicular large B cells, (5)(5)(5) and demonstrate that interfollicular large B cells in lymph node express a somatically mutated IgH.

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