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Soroproteção reduzida após a vacinação sem adjuvante contra influenza pandêmica A/H1N1 em pacientes com artrite reumatoide / Reduced seroprotection after pandemic A/H1N1 influenza adjuvant-free vaccination in patients with rheumatoid arthritis: implications for clinical practiceAna Cristina de Medeiros Ribeiro 28 June 2013 (has links)
Introdução: A vacinação contra a influenza pandêmica A/H1N1 resultou em soroproteção em mais de 85% dos indivíduos saudáveis. Entretanto, dados em pacientes com artrite reumatoide (AR) são escassos. Objetivos: O objetivo deste estudo é avaliar a imunogenicidade e a segurança em curto prazo da vacina contra influenza pandêmica A/H1N1 em pacientes com AR e a influência da atividade da doença e da medicação nesta resposta. Métodos: Trezentos e quarenta pacientes adultos com AR em seguimento e tratamento regular e 234 controles saudáveis foram examinados antes e 21 dias após receber uma dose da vacina sem adjuvante contra influenza A/California/7/2009. A atividade da doença (DAS28), o tratamento em uso e os títulos de anticorpos também foram avaliados. As taxas de soroproteção (títulos de anticorpos >= 1:40) e soroconversão (percentagem de pacientes com aumento de título de anticorpos maior ou igual a 4, se o título pré- vacinal fosse maior ou igual a 1:10; ou título pós-vacinal de pelo menos 1:40, se o título pré-vacinal era menor que 1:10), as médias geométricas dos títulos (MGT) e o fator de incremento das médias geométricas (FI-MGT) foram calculados. Os eventos adversos foram também registrados. Resultados: Os pacientes com AR e os controles tinham taxas pré-vacinais de soroproteção (10,8% vs. 11,5%) e MGT (8,0 vs. 9,3) comparáveis (p>0,05). Após a vacinação, foi observada redução significativa na resposta dos pacientes com AR versus controles (p<0,001) em todos os desfechos sorológicos: taxas de soroproteção (60,0 vs. 82,9%) e soroconversão (53,2% vs. 76,9%), MGT (57,5 vs. 122,9) e FI-MGT (7,2 vs. 13,2). A atividade de doença não prejudicou a soroproteção ou a soroconversão e se manteve estável em 97,4% dos pacientes. O metotrexato e o abatacepte foram associados à redução da resposta vacinal. A vacinação foi bem tolerada, com poucos efeitos adversos. Conclusão: Os dados confirmaram tanto a segurança em curto prazo como, diferente da maioria dos trabalhos com influenza sazonal, a redução da soroproteção em pacientes com AR, não relacionada à atividade de doença e à maioria das medicações em uso (com exceção do metotrexato e do abatacepte). A extrapolação da resposta imunológica de uma vacina para outra pode não ser possível e estratégias específicas de imunização (possivelmente em duas doses) podem ser necessárias / Background: Pandemic influenza A/H1N1 vaccination yielded seroprotection in more than 85% of healthy individuals. However, similar data are scarce in rheumatoid arthritis (RA) patients. Objectives: The objective of this study is to evaluate the immunogenicity and the short-term safety of anti- pandemic influenza A/H1N1 vaccine in RA patients, and the influence of disease activity and medication to the response. Methods: Three hundred and forty adult RA patients in regular follow-up and treatment, and 234 healthy controls were assessed before and 21 days after adjuvant-free influenza A/California/7/2009 vaccine. Disease activity (DAS28), current treatment and anti-pandemic influenza A/H1N1 antibody titres were also evaluated. Seroprotection (antibody titre >=1:40) and seroconversion (the percentage of patients with a fourfold or greater increase in antibody titre, if prevaccination titre was 1:10 or greater, or a postvaccination titre of 1:40 or greater, if prevaccination titre was less than 1:10) rates, geometric mean titres (GMT) and factor increase in geometric mean titre (FI-GMT) were calculated and adverse events registered. Results: RA patients and controls showed similar (p>0.05) prevaccination seroprotection (10.8% vs. 11.5%) and GMT (8.0 vs. 9.3). After vaccination a significant reduction (p<0.001) was observed in all endpoints in RA patients versus controls: seroprotection (60.0 vs. 82.9%; p<0.0001) and seroconversion (53.2% vs. 76.9%) rates, GMT (57.5 vs. 122.9) and FI-GMT (7.2 vs. 13.2). Disease activity did not preclude seroprotection or seroconversion and remained unchanged in 97.4% of patients. Methotrexate and abatacept were associated with reduced responses. Vaccination was well tolerated with minimal adverse events. Conclusions: The data confirmed both short-term anti-pandemic A/H1N1 vaccine safety and, different from most studies with seasonal influenza, reduced seroprotection in RA patients, unrelated to disease activity and to most medications (except methotrexate and abatacept). Extrapolation of xii immune responses from one vaccine to another may therefore not be possible and specific immunization strategies (possibly booster) may be needed
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Imunogenicidade e segurança da vacina contra influenza A H1N1/2009 em pacientes com artrite idiopática juvenil / Immunogenicity and safety of the influenza A H1H1/2009 vaccine in juvenile idiopathic arthritis patientsNádia Emi Aikawa 06 November 2012 (has links)
Introdução: A pandemia de gripe A H1N1 em junho de 2009 resultou em elevadas taxas de hospitalização entre pacientes imunodeprimidos, incluindo pacientes com artrite idiopática juvenil (AIJ). Embora a vacinação seja uma medida eficaz contra complicações da gripe pandêmica, não há estudos na literatura sobre seus efeitos na AIJ. Objetivos: Avaliar a resposta resposta da vacina contra influenza A H1N1/2009 sem adjuvante na AIJ, como uma extensão do estudo anterior de imunogenicidade e segurança em uma grande população de pacientes com doenças reumáticas juvenis. Além disso, avaliar a possível influência de dados demográficos, subtipos de AIJ, atividade da doença e do tratamento sobre a imunogenicidade e o potencial efeito deletério da vacina sobre a doença, particularmente sobre o número de articulações ativas e os marcadores inflamatórios. Métodos: 95 pacientes com AIJ e 91 controles saudáveis foram avaliados antes e 21 dias após a vacinação contra influenza A H1N1/2009 e a sorologia anti-H1N1 foi realizada por ensaio de inibição de hemaglutinação. A avaliação global de atividade da artrite por uma escala visual analógica (EVA) pelo paciente e pelo médico, o Childhood Health Assessment Questionnaire (CHAQ), o número de articulações ativas, as provas de fase aguda (VHS e PCR) e o tratamento foram avaliados antes e após a vacinação. Os eventos adversos foram também reportados. Resultados: Pacientes com AIJ e controles foram comparáveis em relação à média de idade atual (14,9 ± 3,2 vs. 14,6 ± 3,7 anos, p=0,182). A taxa de soroconversão após a vacinação foi significantemente menor nos pacientes com AIJ em relação aos controles (83,2% vs. 95,6%, p=0,008), particularmente no subtipo poliarticular (80% vs. 95,6%, p=0,0098). Os subtipos de AIJ, o número de articulações ativas, as provas de fase aguda, a EVA do paciente e do médico, o CHAQ e a frequencia de uso de DMARDs/imunossupressores foram semelhantes entre os pacientes que soroconverteram versus os que não soroconverteram (p>0,05). Em relação à segurança da vacina, não foi observada piora no número de articulações ativas e nas provas de fase aguda durante o período de estudo. Conclusão: A vacinação contra influenza A H1N1/2009 na AIJ induziu uma resposta humoral reduzida com adequado efeito protetor, independente de parâmetros da doença e tratamento, e com um perfil adequado de segurança da doença. / Introduction: The influenza H1N1 pandemic in June 2009 resulted in high hospitalization rates among immunocompromised patients, including patients with juvenile idiopathic arthritis (JIA). Although vaccination is an effective tool against pandemic flu complications, there are no studies in the literature on its effects in JIA. Objectives: To assess the immune response against the influenza A H1N1/2009 vaccine without adjuvant in JIA as an extension of previous observation of its immunogenicity and safety in a large population of patients with juvenile rheumatic diseases. Moreover to assess the possible influence of demographic data, subtypes of JIA, disease activity and treatment on the immunogenicity and the potential deleterious effect of vaccine on disease itself, particularly on the number of active joints and inflammatory markers. Methods: 95 JIA patients and 91 healthy controls were evaluated before and 21 days after vaccination against influenza A and serology for anti-H1N1 was performed by hemagglutination inhibition assay. The overall assessment of arthritis activity by a visual analogue scale (VAS) by patient and physician, the Childhood Health Assessment Questionnaire (CHAQ), the number of active joints, the acute phase reactants (ESR and CRP) and treatment were evaluated before and after vaccination. Adverse events were also reported. Results: JIA patients and controls were comparable regarding mean current age (14.9 ± 3.2 vs. 14.6 ± 3.7 years, p=0.182). After vaccination seroconversion rate was significantly lower in JIA patients compared to controls (83.2% vs. 95.6%, p=0.008), particularly in polyarticular subtype (80% vs. 95.6%, p=0.0098). JIA subtypes, number of active joints, acute phase reactants, patient and the physician VAS, CHAQ and frequency of use of DMARDs/Immunosuppressants were similar between patients with and without seroconversion (p>0.05). Regarding vaccine safety, no deterioration was observed in the number of active joints and the acute phase reactants during the study period. Conclusion: Influenza A H1N1/2009 vaccination in JIA induces a lower but effective antibody response, probably independent of disease parameters and treatment with an adequate disease safety profile.
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Efeito de um programa progressivo de exercícios de reabilitação funcional e de orientação de auto cuidado sobre a dor, mobilidade e equilíbrio em portadores de artrite reumatóide / Effect of graded exercises and self-care guidance for functional rehabilitation program on pain, balance and mobility in patients with rheumatoid arthritisCarmo, Carolina Mendes do 06 March 2009 (has links)
Introdução: Dor e deformidade nos pés são queixas comuns na Artrite Reumatóide (AR) promovendo alterações no equilíbrio e na mobilidade funcional. A informação somatossensorial dos pés e tornozelos para a regulação da postura e manutenção do equilíbrio tem sido discutida na literatura e apregoa-se que a integridade do pé e da sua informação sensorial são fundamentais para a estabilidade postural. Os programas propostos neste trabalho para estes pacientes integram atenção para a dor e para as deformidades enfocando a melhora da funcionalidade. Objetivos: (i) Verificar os efeitos de um programa progressivo de exercícios de reabilitação funcional e orientação de auto cuidado na dor, no equilíbrio e na mobilidade funcional em portadores de AR, personalizado segundo a necessidade e evolução do paciente, administrado individualmente; (ii) verificar os efeitos de um programa progressivo de exercícios de reabilitação funcional e orientação de auto cuidado na dor, no equilíbrio e na mobilidade funcional em portadores de AR, programa este pré-estabelecido, não personalizado, e administrado em grupo, e: (iii) comparar a eficiência dos dois programas em relação a um grupo controle. Métodos: 5 homens e 40 mulheres portadores de AR com dor e deformidade nos pés foram divididos em 3 grupos segundo ordem de encaminhamento para a fisioterapia: G1- grupo que recebeu o programa progressivo personalizado, G2- grupo controle, e G3- grupo que recebeu o programa progressivo préestabelecido . Todos os pacientes foram avaliados para dor (Escala Numérica de Dor - NRS), saúde dos pés (Questionário Condição de Saúde dos pés FHSQ-Br), equilíbrio (Escala de Berg Balance Berg e Teste de Alcance Funcional TAF) e mobilidade funcional (Teste de Timed Up & Go TUG) ao ingressar no estudo (A1) e após 30 dias (A2), ao completar o programa ou o período controle. O programa de exercícios do G1 foi administrado individualmente e sua progressão seguia o critério de necessidade e evolução do paciente. O programa de exercícios do G3 foi administrado em grupo e sua progressão foi pré-estabelecida em 4 etapas utilizando-se de 4 cartilhas de apoio. Os dois programas foram aplicados duas vezes por semana, durante um período de 30 dias, e eram constituídos de atenção para auto cuidado nos pés, treinamento de equilíbrio e de atividades funcionais. Resultados: Por ocasião do ingresso no estudo (A1) todos os pacientes eram semelhantes em todas as variáveis analisadas, com exceção do teste TUG, que apresentou diferença estatística entre G2 x G1 e G2 x G3 (p< 0,005). Quando analisados os grupos isoladamente, a comparação de A1 e A2 no programa progressivo personalizado - G1, apresentou melhora significativa na NRS (p= 0,002), Berg (p= 0,002), TAF (p= 0,008) e na mobilidade funcional - TUG (p= 0,001). Nos benefícios percebidos FHSQ-Br, apresentou melhora significante no domínio de dor (p=0,015), sapatos (p= 0,012), índice de saúde dos pés (p=0,039) e vigor (p=0,054). A comparação de A1 e A2 no grupo controle - G2, não foi observada diferença significativa em todas as variáveis estudadas. A comparação de A1 e A2 no programa progressivo pré-estabelecido - G3, apresentou melhora significativa no NRS (0,012), Berg (0,002), nos benefícios percebidos sob a dor nos pés (p= 0,013), função dos pés (p= 0,005), saúde geral dos pés (p= 0,001), índice de saúde geral dos pés (p= 0,004), atividade física (p= 0,014), capacidade social (p= 0,001) e índice de saúde (p= 0,015). Comparando-se os três grupos, o G1 apresenta melhora no teste TUG (p=0,001) quando comparado com G2 e G3, no NRS (0,001) quando comparado com G2, enquanto que o G3 apresenta melhora na saúde geral dos pés quando comparado com G1 (p=0,056) e G2 (p=0,037). Conclusão: O programa progressivo personalizado promoveu melhora da dor, do equilíbrio e da mobilidade funcional em portadores de AR além de 4 dos domínios do FHSQBR (dor nos pés, sapatos, índice de saúde dos pés e vigor). O programa progressivo pré-estabelecido promoveu a melhora da dor, do equilíbrio e dos benefícios percebidos em portadores de AR e em 8 domínios do FHSQ-BR (dor nos pés, função dos pés, saúde geral dos pés, índice de saúde geral dos pés, atividade física, capacidade social, índice de saúde). Comparando os programas, G1 apresentou melhora da mobilidade funcional e G3 apresentou melhora no benefício percebido em saúde geral dos pés. / Background: Rheumatoid arthritis (RA) is a common systemic disease in which foot involvement has been largely claimed. A functional foot must reveal musculoskeletal integrity such as joint alignment and range of motion, mobility and muscular strength. It is essential for postural and balance control as well as effective propulsion during gait. Impairment of foot somatosensory information leads to postural instability, and produce a severe negative impact on mobility and functional capacity. Plantar sensitivity is also decreased in patients with RA, reinforcing that RA patients show deficits in balance and functional activities as a result of alterations on foot functioning. Objective: To verify comparatively the effects of graded exercise, personalized or pre-established, for functional rehabilitation programs on pain, balance and mobility in patients with rheumatoid arthritis (RA). Methods: 5 male and 40 female patients with RA, pain and foot deformity were sequentially allocated into three groups: G1- personalized program, G2- control group, and G3- pre-established program All patients were assessed in the beginning the study (A1) and after 30 days (A2), for pain (Numerical Rating Scale - NRS), perceived benefits (Foot Health Status Questionnaire - FHSQ-Br), balance (Berg Balance Scale - Berg, Functional Reach - FR) and functional mobility (Timed Up & Go - TUG). G1 and G3 underwent functional rehabilitation program for 30 days. The program comprised of graded exercises and self-care guidance for functional rehabilitation and were applied on two weekly sessions of 60 minutes each, during 4 weeks. Results: Analysis of A1 revealed no significant difference for all variables in the three groups, except for TUG test. Comparing G2 x G1 and G2 x G3 patients from control group, G2, needed shorter time to the completion of the test when compared to G1 and G3. Comparison from to A1 and A2 in G1, revealed significant improvement in NRS, Berg, FR, and in TUG. FHSQ-Br showed significant improvement in the domain of pain, shoes, foot health index, and vigour. Comparison of A1 and A2 in the G3, showed significant improvement in NRS, Berg, and in the domains of pain, function, general foot health, general foot health index, physical activity, social capability, and general health index for FHSQ-Br. Variation from A1 to A2 in G2 revealed no significant difference. Comparing the three groups, G1 showed improvement in TUG, compared to G2 and G3, in NRS compared with G2, whereas G3 revealed improvement in the observed benefit in general foot health compared to G1 and G2. Conclusion: Both programs revealed benefits for patients with RA. In the personalized graded exercises, utmost improvements were found mainly in the objective variables, pain, balance, and functional mobility, beyond 4 out of 10 FHSQ-Br domains whereas in the pre-established graded exercise, in the perceived benefit, 8 out of 10 FHSQ-Br domains beyond pain and balance. domains whereas in the pre-established graded exercise, in the perceived benefit, 8 out of 10 FHSQ-Br domains beyond pain and balance.
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Osteopontin and osteoclasts in rheumatoid arthritis and osteoarthritisLuukkonen, J. (Jani) 29 October 2019 (has links)
Abstract
Rheumatoid arthritis and osteoarthritis are two chronic joint diseases, which cause two of the largest socioeconomical burdens among all joint diseases according to the World Health Organization. Both diseases are associated with changes in bone structure and bone cell, especially osteoclast, function. The etiology or pathogenesis of these diseases are not completely understood. Traditionally, osteoarthritis is seen as a disease resulting from mechanical wear of cartilage and bone, and rheumatoid arthritis as an autoinflammatory disease of synovial tissue. However, also in osteoarthritis chronic inflammation is present in synovial tissue, and in rheumatoid arthritis large changes in bone structure are seen. The field of study focusing on this connection between inflammation and bone is called osteoimmunology and it can explain many features of these chronic diseases linking joint health to disturbances in bone homeostasis.
Here, the study focused on the function of osteoclasts in normal and pathological environments, and on the factors that have an effect on bone resorption, with a special emphasis on the protein osteopontin. Samples of synovial fluid and serum from rheumatoid arthritis and osteoarthritis patients were analyzed for factors affecting osteoclasts, and in vitro cell cultures of human derived osteoclasts were used to analyze osteoclast function in normal and pathological environment.
The phosphorylation of osteopontin was found to be increased in rheumatoid arthritis, along with multiple other inflammatory factors that also affect osteoclasts, such as IL-6, IL-8 and VEGF. Osteoclast cell cultures showed how the use of different patient samples significantly affected osteoclastogenesis, due to so-called inflammatory osteoclastogenesis. Additionally, we show that osteoclasts deposit osteopontin into the resorption lacunae during bone resorption.
Based on the results, the inflammatory component present in both osteoarthritis and rheumatoid arthritis significantly affects osteoclast function, and its further study in the future may reveal new therapeutic possibilities. Especially the new discoveries of osteopontin’s role in normal osteoclast function and its changes seen between osteoarthritis and rheumatoid arthritis may prove to have therapeutic potential. / Tiivistelmä
Nivelreuma ja nivelrikko ovat kroonisia nivelsairauksia, jotka Maailman terveysjärjestön (WHO) mukaan aiheuttavat eniten sosioekonomista haittaa. Molemmissa sairauksissa luiden rakenteessa ja luusolujen, erityisesti osteoklastien, toiminnassa tapahtuu muutoksia. Kummankaan taudin etiologiaa tai patogeneesiä ei täysin tunneta. Perinteisesti ajatellaan, että nivelrikko johtuu rusto- ja luukudoksen mekaanisesta kulumisesta ja nivelreuma nivelkalvon autoinflammatoorisesta tulehduksesta. Kuitenkin nivelrikossa nähdään myös selkeä nivelkalvon krooninen tulehdus ja nivelreumassa suuria luun rakenteen muutoksia. Tutkimusala, joka tutkii tulehduksen ja luun yhteyttä, on nimeltään osteoimmunologia.
Tässä väitöskirjassa tutkitaan osteoklastien toimintaa ja niihin vaikuttavia tekijöitä, erityisesti proteiini osteopontiinia, normaalissa ja tautiympäristössä. Analysoin osteoklasteihin vaikuttavia tekijöitä nivelrikko- ja nivelreumapotilaiden näytteistä sekä osteoklastien toimintaa soluviljelmissä. Soluviljelmissä käytettiin nivelreuma- ja nivelrikkopotilaiden näytteitä mahdollisimman totuudenmukaisen ympäristön luomiseksi osteoklasteille.
Tutkimuksessa osoitettiin, kuinka osteopontiinin fosforylaatio on lisääntynyt nivelreumapotilaiden nivelnesteessä. Myös useiden muiden osteoklasteihin vaikuttavien tekijöiden, kuten IL-6:n, IL-8:n ja VEGF:n, havaittiin lisääntyneen nivelreumassa. Osteoklastien soluviljelmissä havaittiin selkeät erot siinä, miten eri potilasnäytteet vaikuttavat osteoklasteihin ja erityisesti tulehduksen aiheuttamaan osteoklastien syntyyn. Osoitan myös, miten osteoklastit erittävät osteopontiinia luunhajotuskuoppaan luun hajotuksen aikana.
Tutkimustulosten mukaan krooninen tulehdustila nivelrikossa ja nivelreumassa vaikuttaa huomattavasti osteoklastien toimintaan. Uskon, että lisätutkimukset tällä saralla voivat paljastaa uusia hoidollisia mahdollisuuksia. Erityisesti uudet löydökset osteopontiinin roolista osteoklastien toiminnassa sekä muutoksista nivelrikossa ja nivelreumassa vaativat jatkotutkimuksia, jotta proteiinin kliininen merkittävyys saadaan selvitettyä.
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Asymmetric Synthesis of C-Glycosylated Amino Acids : Incorporation in Collagen Glycopeptides and Evaluation in a Model for Rheumatoid ArthritisGustafsson, Tomas January 2005 (has links)
<p>This thesis describes stereoselective syntheses of four amino acids, three of which are C-glycosidic analogues of glycosylated amino acids. The overall goal of the project was to probe the interactions between MHC molecules, glycopeptide antigens and T cell receptors, that are essential for development of collagen induced arthritis. Collagen induced arthritis is a frequently used mouse model for rheumatoid arthritis, an autoimmune disease that attacks joint cartilage and leads to a painful and eventually crippling condition.</p><p>The thesis is based on four studies. The first study describes the synthesis of hydroxylysine, an amino acid that is found in collagen and is an important constituent of the glycopeptide proposed as an antigen in collagen induced arthritis. During the synthesis of hydroxylysine some new insight into the mechanism of the reductive opening of <i>p</i>-methoxybenzylidene acetals was obtained.</p><p>The remaining three studies deals with the synthesis of C-glycosidic analogues of glycosylated amino acids, hydroxy norvaline, threonine and hydroxylysine.The synthesis of each amino acid required control of several stereogenic centra and utilizes a variety of approaches such as use of stereoselective reactions, chiral auxilaries, chiral templates and asymmetric catalysis.</p><p>The C-glycosidic analogues of galactosylated hydroxynorvaline and hydroxylysine were incorporated in glycopeptides from type II collagen and evaluated in T cell response assays. It was found that the T cells were stimulated by the C-glycopeptides, but that higher concentrations were required than for the native O-glycopeptide</p>
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The MHC-glycopeptide-T cell interaction in collagen induced arthritis : a study using glycopeptides, isosteres and statistical molecular design in a mouse model for rheumatoid arthritisHolm, Lotta January 2006 (has links)
<p>Rheumatoid arthritis (RA) is an autoimmune disease affecting approximately 1% of the population in the western world. It is characterised by a tissue specific attack of cartilage in peripheral joints. Collagen induced arthritis (CIA) is one of the most commonly used animal models for (RA), with similar symptoms and histopathology. CIA is induced by immunisation of mice with type II collagen (CII), and the immunodominant part was previously found to be located between residues 256-270. This thesis describes the interaction between the MHC molecule, glycopeptide antigens from CII and the T cells that is essential in development of CIA. The glycopeptide properties for binding to the mouse MHC molecule Aq have been studied, as well as interaction points in the glycopeptide that are critical for stimulation of a T-cell response.</p><p>The thesis is based on five studies. In the first paper the minimal glycopeptide core, that is required for binding to the Aq molecule while still giving a full T cell response was determined. The second paper studied the roles of amino acid side-chains and a backbone amide bond as T-cell contact points. In the third paper the hydrogen bond donor-acceptor characteristics of the 4-OH galactose hydroxyl group of the glycopeptide was studied in detail. In the fourth paper we established a structure activity relationship (QSAR model) for (glyco)peptide binding to the Aq molecule. Finally, the stereochemical requirements for glycopeptide binding to the Aq molecule and for T-cell recognition was studied in the fifth paper.</p><p>The study was performed using collagen glycopeptide analogues, which were synthesised on solid phase. Amide bond and hydroxyl group isosteres were introduced for study of hydrogen bond donor-acceptor characteristics. Statistical methods were used to design a representative peptide test set and in establishing a QSAR model.</p><p>The results give a deeper understanding of the interactions involved in the ternary MHC-glycopeptide-T cell complex. This information contributes to research directed towards finding new treatments for RA.</p>
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Fcγ Receptors in the Immune ResponseDíaz de Ståhl, Teresita January 2001 (has links)
<p>Circulating immune complexes play an important role in the modulation of antibody responses and in the pathogenesis of immune diseases. This thesis deals with the <i>in vivo </i>regulatory properties of antibodies and their specific Fc receptors.</p><p>The immunosuppressive function of IgG is used clinically, to prevent rhesus-negative women from becoming sensitized to rhesus-positive erythrocytes from the fetus. The mechanism behind this regulation is poorly understood but involvement of a receptor for IgG, FcγRII, has been suggested. It is shown in this thesis that IgG and also IgE induce immunosuppression against sheep erythrocytes to a similar extent both in mice lacking all the known Fc receptors as in wild-type animals. These findings imply that antibody-mediated suppression of humoral responses against particulate antigens is Fc-independent and that the major operating mechanism is masking of epitopes.</p><p>Immunization with soluble antigens in complex with specific IgG leads to an augmentation of antibody production. The cellular mechanism behind this control is examined here and it is found that the capture of IgG2a immune complexes by a bone marrow-derived cell expressing FcγRI (and FcγRIII) is essential. An analysis of the ability of IgG3 to mediate this regulation indicated that, in contrast, this subclass of IgG augments antibody responses independently of FcγRI (and FcγRIII). These findings suggest that distinct mechanisms mediate the enhancing effect of different subclasses of antibodies.</p><p>Finally, the contribution of FcγRIII was studied in the development of collagen-induced arthritis (CIA), an animal model for rheumatoid arthritis in humans. It was discovered that while DBA/1 wild-type control mice frequently developed severe CIA, with high incidence, FcγRIII-deficient mice were almost completely protected, indicating a crucial role for FcγRIII in CIA.</p><p>The results presented here help to understand how immune complexes regulate immune responses <i>in vivo</i> and show that Fc receptors for IgG, if involved, could be new targets for the treatment of immune complex-related disorders.</p>
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Meals and Food in Older Women : Health Perceptions, Eating Habits, and Food ManagementGustafsson, Kerstin January 2002 (has links)
<p>The aim was to describe and explore the food-related work and eating habits of older community-dwelling women, with Parkinson’s disease, rheumatoid arthritis or stroke or without these diseases. The major focus is on health perceptions, eating habits and meal support. A theoretical framework based on cultural and health theories was adopted. A total of 91 women between 64 and 88 years were visited in their homes, a food survey was performed consisting of a 24h recall and an estimated three-day food diary was introduced. Seventy-two of the women also took part in qualitative interviews with an ethnographic approach. Approximately one week later, another 24h recall was carried out at a second visit, or for the non-disabled women by telephone. The analyses revealed that many women were influenced by the prevailing health message and tried to eat a healthy diet. It was also important to them to enjoy their preferred foods, but this gave some women a bad conscience, while others perceived their usual foods as wholesome to eat. Health promotion for older women needs to incorporate the women’s own cultural context, their perceptions of food-related health, and their wish to adhere to their usual habits. Women with disease, frailty and who had become alone reported simplified food-related work and poor eating habits. However, management of these duties was highly valued, and women strove to cook by themselves as long as possible when disability became a threat. This resulted in a trend towards less nourishing cooked meals for women with disabilities. Thus, many women with these diseases living at home need support with their meals. This has to be planned in collaboration with the woman and build on her cultural values. The help must be performed with respect for the woman’s sense of order, be given sufficient time, and acknowledge her self-determination.</p>
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Asymmetric Synthesis of C-Glycosylated Amino Acids : Incorporation in Collagen Glycopeptides and Evaluation in a Model for Rheumatoid ArthritisGustafsson, Tomas January 2005 (has links)
This thesis describes stereoselective syntheses of four amino acids, three of which are C-glycosidic analogues of glycosylated amino acids. The overall goal of the project was to probe the interactions between MHC molecules, glycopeptide antigens and T cell receptors, that are essential for development of collagen induced arthritis. Collagen induced arthritis is a frequently used mouse model for rheumatoid arthritis, an autoimmune disease that attacks joint cartilage and leads to a painful and eventually crippling condition. The thesis is based on four studies. The first study describes the synthesis of hydroxylysine, an amino acid that is found in collagen and is an important constituent of the glycopeptide proposed as an antigen in collagen induced arthritis. During the synthesis of hydroxylysine some new insight into the mechanism of the reductive opening of p-methoxybenzylidene acetals was obtained. The remaining three studies deals with the synthesis of C-glycosidic analogues of glycosylated amino acids, hydroxy norvaline, threonine and hydroxylysine.The synthesis of each amino acid required control of several stereogenic centra and utilizes a variety of approaches such as use of stereoselective reactions, chiral auxilaries, chiral templates and asymmetric catalysis. The C-glycosidic analogues of galactosylated hydroxynorvaline and hydroxylysine were incorporated in glycopeptides from type II collagen and evaluated in T cell response assays. It was found that the T cells were stimulated by the C-glycopeptides, but that higher concentrations were required than for the native O-glycopeptide
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Fcγ Receptors in the Immune ResponseDíaz de Ståhl, Teresita January 2001 (has links)
Circulating immune complexes play an important role in the modulation of antibody responses and in the pathogenesis of immune diseases. This thesis deals with the in vivo regulatory properties of antibodies and their specific Fc receptors. The immunosuppressive function of IgG is used clinically, to prevent rhesus-negative women from becoming sensitized to rhesus-positive erythrocytes from the fetus. The mechanism behind this regulation is poorly understood but involvement of a receptor for IgG, FcγRII, has been suggested. It is shown in this thesis that IgG and also IgE induce immunosuppression against sheep erythrocytes to a similar extent both in mice lacking all the known Fc receptors as in wild-type animals. These findings imply that antibody-mediated suppression of humoral responses against particulate antigens is Fc-independent and that the major operating mechanism is masking of epitopes. Immunization with soluble antigens in complex with specific IgG leads to an augmentation of antibody production. The cellular mechanism behind this control is examined here and it is found that the capture of IgG2a immune complexes by a bone marrow-derived cell expressing FcγRI (and FcγRIII) is essential. An analysis of the ability of IgG3 to mediate this regulation indicated that, in contrast, this subclass of IgG augments antibody responses independently of FcγRI (and FcγRIII). These findings suggest that distinct mechanisms mediate the enhancing effect of different subclasses of antibodies. Finally, the contribution of FcγRIII was studied in the development of collagen-induced arthritis (CIA), an animal model for rheumatoid arthritis in humans. It was discovered that while DBA/1 wild-type control mice frequently developed severe CIA, with high incidence, FcγRIII-deficient mice were almost completely protected, indicating a crucial role for FcγRIII in CIA. The results presented here help to understand how immune complexes regulate immune responses in vivo and show that Fc receptors for IgG, if involved, could be new targets for the treatment of immune complex-related disorders.
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