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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.
111

Cannabinoids induce immunoglobulin class switching to IgE in B lymphocytes /

Agudelo, Marisela. January 2009 (has links)
Dissertation (Ph.D.)--University of South Florida, 2009. / Includes vita. Includes bibliographical references. Also available online.
112

Life History Tradeoffs Between Testosterone and Immune Function Among Shuar Forager-Horticulturalists of Amazonian Ecuador

Gildner, Theresa 06 September 2018 (has links)
The sex hormone testosterone supports male reproduction. However, testosterone is hypothesized to suppress immune activity, resulting in a tradeoff between energetic investment in reproductive effort and immune function. The Immunocompetence Handicap Hypothesis (ICHH) therefore argues that testosterone-linked masculine traits honestly signal health status to prospective mates, as only uninfected males should be able to maintain high testosterone levels. Still, this proposed tradeoff remains poorly tested among human men, especially among natural fertility populations experiencing high infectious disease burdens. This dissertation therefore tested the ICHH among indigenous Shuar men of Amazonian Ecuador. Specifically, this project examined testosterone variation patterns and assessed how male investment in reproductive effort is associated with reproductive success and immune function. The first study tested testosterone level variation among Shuar men in relation to body composition, age, and style of life factors. This study demonstrated that age and BMI interactions shape testosterone levels in complex ways, such that the relationship between body composition and testosterone profile varies throughout the life course. The second study investigated whether individual reproductive success was significantly influenced by masculine trait development and parasite load. These results failed to support the hypotheses that masculine traits increased reproductive success or honestly signaled lack of parasitic disease. Instead, a significant positive association was observed between a composite score of masculine traits and Ascaris lumbricoides infection load; suggesting that male investment in reproductive effort may increase parasitic infection risk. The final study assessed whether testosterone levels were negatively associated with four measures of immune function (parasite load, C-Reactive Protein [CRP], Immunoglobulin-G [IgG], and Immunoglobulin-E [IgE]). Testosterone levels were inversely associated with CRP levels and a positive relationship between testosterone levels and Trichuris trichiura infection load was documented, suggesting increased investment in reproductive effort may suppress some aspects of immune function and increase parasite burden. Overall, these studies fail to support the ICHH, but do indicate a context-dependent tradeoff between energetic investment in male reproductive effort and some aspects of immune function; thereby demonstrating complex interactions between physical characteristics, physiological processes, and immune activity in human men. This dissertation includes unpublished, co-authored material.
113

The regulatory effects of circulating normal immunoglobulins on autophagy and Th17 response / Les effets régulateurs des immunoglobulines circulantes normales sur l'autophagie et la réponse Th 17

Das, Mrinmoy 07 September 2017 (has links)
Les immunoglobulines circulantes jouent un rôle critique dans l’homéostasie immune en modulant les fonctions des cellules du système immunitaire. Au cours de ma thèse, j’ai exploré les effets régulateurs des immunoglobulines G thérapeutiques (IVIG) et des immunoglobulines A monomériques circulantes (mIgA) sur l’autophagie et les réponses Th17 respectivement. Les IVIg sont une préparation thérapeutique d’IgG normales poolées. Elles ont utilisées comme agent anti-inflammatoire dans le traitement de maladies auto-immunes et inflammatoires variées. Cependant, les mécanismes ne sont pas complètement élucidés et plusieurs mécanismes mutuels et non exclusifs ont été proposés. L’autophagie est un important processus biologique impliquant la dégradation lysosomale des composants cellulaires endommagés et des protéines mal repliées. Il y a plusieurs preuves montrant l’implication de l’autophagie dans les maladies auto-immunes et auto-inflammatoires incluant la découverte de polymorphismes dans des gènes liés à l’autophagie. J’ai montré que l’induction de l’autophagie par les IVIG représente un nouveau mécanisme d’action permettant leur effet thérapeutique dans les maladies auto-immunes et inflammatoires. Les Th17 représentent une cible attractive pour traiter plusieurs maladies inflammatoires et auto-immunes. Malgré le fait qu’elles sont le deuxième anticorps le plus abondant dans la circulation, la function immunorégulatrice des IgA n’est relativement pas explorée. J’ai montré que les IgA monomériques (mIgA) inhibent la différentiation et l’amplification des cellules Th17 humaines et la production de leur cytokine effectrice IL-17A. / Circulating immunoglobulins play a critical role in the immune homeostasis by modulating the functions of immune cells. In my thesis, I investigated the regulatory effects of therapeutic immunoglobulin G (IVIG) and circulating monomeric immunoglobulin A (mIgA) on autophagy and human Th17 response respectively. IVIG is a therapeutic preparation of pooled normal IgG. It is used as an anti-inflammatory agent in the treatment of a wide variety of autoimmune and inflammatory diseases. However, the mechanisms are not yet fully elucidated and several mutually non-exclusive mechanisms have been proposed. Autophagy is an important biological process involving lysosomal degradation of damaged cellular components and misfolded proteins. There are several evidences that support the involvement of autophagy in autoimmune and auto- inflammatory disorders including the discovery of polymorphisms in autophagy-related genes. I show that induction of autophagy by IVIG represents a novel mechanism of action in achieving therapeutic effect in autoimmune and inflammatory diseases. Th17 cells represent an attractive target to treat several inflammatory and autoimmune diseases. Despite being second most abundant antibody in the circulation, the immunoregulatory function of IgA is relatively unexplored. I have shown that monomeric IgA (mIgA) inhibits differentiation and amplification of human Th17 cells and the production of their effector cytokine IL-17A.
114

Effect of Anterior or Ventromedial Hypothalamic Stimulation on Immunoglobulin G

Lambert, Paul L. (Paul Louis) 08 1900 (has links)
Although research has linked central nervous system activity with changes in immunoresponsivity, research on the possible role of the central nervous system in altering a specific class of antibody is lacking. This study was an investigation of the possible relationship between anterior or medial hypothalamic functions on Immunoglobulin G. concentrations in rat serum. Thirty-six male albino rats were randomly assigned to three groups of equal size. Animals within the anterior hypothalamic group received bilateral electrode implants in the anterior hypothalamus while animals in the medial hypothalamic group received electrode implants within the ventromedial area of the hypothalamus. A control group received bilateral electrode implants within the lateral hypothalamus. Electrical brain stimulation was administered to animals in both experimental groups. Control animals spent a comparable time in an operant chamber but did not receive electrical brain stimulation. Following brain stimulation of animals within the experimental groups, Immunoglobulin G. concentrations were determined for all groups 3, 6, 12, and 24 hours post-stimulation sessions.
115

Radiomarquage au 99mTc des IgA et IgG : optimisation du marquage, étude in vitro, biodistribution chez l'animal sain et sur modèle tumoral / Immunoglobulins A and G radiolabeling with 99mTc : labeling optimization, in vitro evaluations, biodistribution in healthy animals and on tumoral model

Carpenet Guéry, Hélène 10 December 2015 (has links)
Depuis leur découverte en 1975 par Köhler et Milstein, le monde des Ac monoclonaux a beaucoup évolué. Ils occupent actuellement une place prépondérante dans la prise en charge de nombreux cancers. De nos jours, les Ac monoclonaux, ayant une AMM ou en essai clinique, sont tous de classe IgG voire IgG1. Cette classe d’Ac a cependant montré des limites à son utilisation, et l’étude d’autres isotypes d’Ac, comme les IgA, pourrait être intéressante. Les IgA, isotype d’Ac particulier en raison notamment de leur hétérogénéité dans les formes moléculaires, demeurent peu étudiées à l’instar des IgG. Dans ce travail, nous proposons un radiomarquage des IgA monomériques, polymériques et sécrétoires, avec le 99mTc par une méthode indirecte impliquant le 2-iminothiolane et le cœur tricarbonyl. Par le biais de ce radiomarquage, la biodistribution des IgA monomériques et polymériques après administration i.v. a été évaluée chez l’animal sain et chez l’animal porteur de tumeur à localisation muqueuse. Ces études nous ont permis d’entrevoir le potentiel diagnostique des IgA, mais aussi leur intérêt en thérapie ciblée de tumeurs à localisation muqueuse. D’autre part, grâce à leur résistance enzymatique et au phénomène de retranscytose, une nouvelle voie d’administration des Ac monoclonaux pourrait être développée. Dans cette optique, des IgA sécrétoires ont été administrées par voie orale lors d’études préliminaires de biodistribution. / Since their discovery in 1975, by Köhler and Milstein, monoclonal antibodies (mAbs) world has significantly evolved and they currently hold a prominent place in cancers care. Today, the mAbs, having a marketing authorization or in clinical trial, are all IgG class (IgG1). However, this Ab class showed limitations on its use, and the study of other isotypes, such as IgA, could be interesting. Unlike IgG, IgA, original isotype particularly because of their heterogeneity in molecular forms, remains understudied. In this work, we propose a radiolabeling of monomeric, polymeric and secretory IgA with 99mTc by an indirect method, involving 2-iminothiolane and tricarbonyl core. Biodistribution of radiolabeled monomeric and polymeric IgA was evaluated, after intravenous administration, in healthy animals and in mucosal tumor-bearing animals. These studies have allowed us to glimpse the IgA diagnostic potential, but also their interest in targeted therapy of tumors with mucosal localization. Moreover, thanks to their enzymatic strength and retranscytosis, a new administration route of mAbs could be developed. In this context, secretory IgA were administered orally in preliminary biodistribution studies.
116

Effect of Cell-Specific, Music-Mediated Mental Imagery on Secretory Immunoglobulin A (sIgA)

Rider, Mark Sterling 08 1900 (has links)
This study was an investigation of the effects of physiologically-oriented mental imagery on immune functioning. College students with normal medical histories were randomly selected to one of three groups. Subjects in Group 1 participated in short educational training on the production of secretory immunoglobulin A. They were then tested on salivary IgA, skin temperature and the Profile of Mood States (POMS) before and after listening to a 17-minute tape of imagery instructions with specially-composed background "entrainment" music, designed to enhance imagery. Subjects in Group 2 (placebo controls) listened to the same music but received no formal training on the immune system. Group 3 acted as a control and subjects were tested before and after 17 minutes of no activity. Treatment groups listened to their tapes at home on a bi-daily basis for six weeks. All groups were again tested at Weeks 3 and 6. Secretory IgA was analyzed using standard radial immuno-diffusion techniques. Repeated measures analyses of variance with planned orthogonal contrasts were used to evaluate the data. Significant overall increases (p < .05) were found between pre- and posttests for all three trials. Groups 1 and 2 combined (treatment groups) yielded significantly greater increases in slgA over Group 3 (control) for all three trials. Group 1 (imagery) was significantly higher than Group 2 (music) in antibody production for Trials 2 and 3. No group differences were noted in saliva volume or skin temperature, indicating that autonomic physiological mechanisms were not responsible for differences in antibody production. POMS changes more often favored Group 1. Symptomatology, recorded by subjects at weeks three and six, was significantly lower for three symptoms (rapid heartbeat, breathing difficulty, and jaw clenching), again favoring both treatment groups over the control group. Conclusions were that CNS-mediated immunoenhancement through mental imagery is possible.
117

Disulfide bond formation between dimeric immunoglobulin A and the polymeric immunoglobulin receptor in cultured epithelial cells and rat liver

Chintalacharuvu, Koteswara Rao January 1991 (has links)
No description available.
118

Aspectos clínico-laboratoriais na evolução de pacientes com deficiência de imunoglobulina A diagnosticados na infância e de seus familiares / Clinical and laboratorial features from patients with IgA deficiency diagnosed in childhood and from their relatives

Fahl, Kristine 24 June 2008 (has links)
A deficiência de imunoglobulina A (DIgA) é a imunodeficiência primária mais comum com prevalência de 1: 223 a 1:1000 em estudos epidemiológcos, sendo menos freqüente em populações asiáticas. As manifestações clínicas variam desde indivíduos assintomáticos até aqueles com manifestações atópicas, auto-imunes ou infecciosas. Entre estas últimas destacam-se os acometimentos dos tratos respiratório e digestório. Associação com outras imunodeficiências primárias tem sido reportada, em especial a imunodeficiência comum variável e a deficiência de subclasses de imunoglobulina G. Os objetivos deste estudo foram a avaliação dos pacientes com DIgA, diagnosticados na infância, após a segunda década da vida e a avaliação diagnóstica de seus familiares quanto aos aspectos clínicos e laboratoriais. A metodologia utilizou, para o diagnóstico de DIgA, o critério adotado pelo ESID/PAGID (1999). Foi realizada a avaliação das concentrações de imunoglobulina A(IgA) e imunoglobulina M (IgM), na saliva e a pesquisa de auto-anticorpos séricos (Anti-tireóide, FR,FAN) nos pacientes e familiares com DIgA. Realizou-se uma curva de distribuição de IgM salivar em indivíduos normais para comparação com os pacientes DIgA. Os resultados mostraram a avaliação dos 34 pacientes (19 do sexo feminino) com deficiência de imunoglobulina A (DIgA) com idade superior a 10 anos (variação: 10 à 52 anos), sendo 27 deles diagnosticados na infância e 7 familiares dos 62, que responderam à convocação. Considerando-se todos os indivíduos com DIgA, processos infecciosos (de repetição ou graves) ocorreram em 91,2%, manifestações atópicas em 58,8% e auto-imunidade em 52,9%. Manifestações clínicas de auto-imunidade foram observadas em 14/18 indivíduos, sendo que sete foram diagnosticados após 10 anos de idade, por ocasião da realização da pesquisa. Auto-anticorpos foram observados em 10 pacientes, sendo quatro pacientes assintomáticos. Fator reumatóide não foi detectado nesta casuística. Tireoidopatias (seis casos) e artropatias (quatro casos) foram as manifestações clínicas auto-imunes mais observadas. As concentrações de IgM salivar mostraramse elevadas em todos, exceto cinco casos. A comparação dessas concentrações nos grupos com e sem auto-imunidade não mostrou diferença significante (p= 0,48). As conclusões desta pesquisa mostraram os processos infecciosos como as manifestações clínicas mais freqüentes nos pacientes com DIgA, observando-se, porém, uma relevante presença de auto-imunidade nestes pacientes quando reavaliados após a segunda década de vida. Este fato alerta para a necessidade de avaliação rotineira de fenômenos auto- imunes nestes pacientes, durante seguimento. As concentrações de IgM salivar foram semelhantes em pacientes com DIgA com e sem auto-imunidade. Auto-anticorpos foram detectados independentemente da presença de sintomatologia clínica, sendo os mais encontrados aqueles relacionados à tireóide. Os familiares de primeiro grau dos pacientes com DIgA devem ser avaliados, tanto para diagnóstico de imunodeficiências como para detecção de fenômenos auto-imunes, permitindo assim o diagnóstico e abordagens precoces de ambas condições. / IgA deficiency (IgAD) is the most frequent primary immunodeficiency. Its prevalence varies from 1:223 to 1:1000 in epidemiological studies, but in asiatic populations it is uncommon. The clinical manifestations of IgAD are spectral, ranging from asymptomatic patients to recurrent infections, allergic symptoms and/or autoimmunity conditions. The most common infections frequently associated to IgAD involve respiratory and gastrointestinal tracts. The association with other primary immunodeficiency such as common variable immunodeficiency and immunoglobulin G subclasses deficiency has been reported. The aim of this study is to describe clinical and laboratorial evolution regarding autoimmune manifestations in IgAD patients diagnosed during the first years of life and after the second decade and their relatives diagnosed during this study. Laboratorial data included immunoglobulins A and M levels in saliva and auto-antibody screening in immunoglobulin A deficient relatives and patient. The criterion adopted for IgAD diagnosis was defined by Pan-American Group for Immunodeficiency and European Society for Immunodeficiency. The results showed 34 (19 female) immunoglobulin A deficient patients (IgAD) over 10 years of age (range: 10-52 years), 27 of them diagnosed during their childhood, and seven adults detected among 62 screened relatives. Recurrent infections were diagnosed in 91.2% of cases, atopic manifestations in 58.8% and autoimmune clinical manifestation in 52.9%. Autoimmune clinical manifestations were observed in 14 of our 18 IgA deficient patients and relatives with autoimmunity phenomena and seven of them diagnosed only over 10 years old during the study. Auto-antibodies were observed in (10/18) of patients and relatives, with four of them (asymptomatic) showing only the presence of auto-antibodies. Thyroid and osteo-articular involvement (six and four cases, respectively) were the most frequent clinical autoimmune manifestations. The rheumatoid factor was not detected in this casuistic. Auto-antibodies had no statistical difference among patients with or without autoimmunity phenomena. High salivary IgM concentrations were detected in all IgA deficient patients and relatives, except five cases. The comparison of these concentrations in the groups with and without autoimmunity did not show significant difference (p=.0, 48). In conclusion, recurrent infections were the most frequent clinical manifestations of IgA deficient patients and also autoimmune diseases, after the second decade of life. This fact at this series reinforced the necessity of active search for autoimmune conditions diagnosis in these patients. IgM levels showed no statistical difference among IgA deficient patients and relatives with or without autoimmunity. Auto-antibodies, mainly anti-thyroid antibodies, were detected in patients independently of autoimmunity clinical manifestation presence. This study showed the importance of the first degree relatives of IgA deficient patients evaluation, focusing as immunodeficiency as autoimmune disease, permiting an earlier diagnosis of both conditions and an adequate approach to optimize the clinical management and improvement of quality of life of IgAD patients.
119

Aspectos clínico-laboratoriais na evolução de pacientes com deficiência de imunoglobulina A diagnosticados na infância e de seus familiares / Clinical and laboratorial features from patients with IgA deficiency diagnosed in childhood and from their relatives

Kristine Fahl 24 June 2008 (has links)
A deficiência de imunoglobulina A (DIgA) é a imunodeficiência primária mais comum com prevalência de 1: 223 a 1:1000 em estudos epidemiológcos, sendo menos freqüente em populações asiáticas. As manifestações clínicas variam desde indivíduos assintomáticos até aqueles com manifestações atópicas, auto-imunes ou infecciosas. Entre estas últimas destacam-se os acometimentos dos tratos respiratório e digestório. Associação com outras imunodeficiências primárias tem sido reportada, em especial a imunodeficiência comum variável e a deficiência de subclasses de imunoglobulina G. Os objetivos deste estudo foram a avaliação dos pacientes com DIgA, diagnosticados na infância, após a segunda década da vida e a avaliação diagnóstica de seus familiares quanto aos aspectos clínicos e laboratoriais. A metodologia utilizou, para o diagnóstico de DIgA, o critério adotado pelo ESID/PAGID (1999). Foi realizada a avaliação das concentrações de imunoglobulina A(IgA) e imunoglobulina M (IgM), na saliva e a pesquisa de auto-anticorpos séricos (Anti-tireóide, FR,FAN) nos pacientes e familiares com DIgA. Realizou-se uma curva de distribuição de IgM salivar em indivíduos normais para comparação com os pacientes DIgA. Os resultados mostraram a avaliação dos 34 pacientes (19 do sexo feminino) com deficiência de imunoglobulina A (DIgA) com idade superior a 10 anos (variação: 10 à 52 anos), sendo 27 deles diagnosticados na infância e 7 familiares dos 62, que responderam à convocação. Considerando-se todos os indivíduos com DIgA, processos infecciosos (de repetição ou graves) ocorreram em 91,2%, manifestações atópicas em 58,8% e auto-imunidade em 52,9%. Manifestações clínicas de auto-imunidade foram observadas em 14/18 indivíduos, sendo que sete foram diagnosticados após 10 anos de idade, por ocasião da realização da pesquisa. Auto-anticorpos foram observados em 10 pacientes, sendo quatro pacientes assintomáticos. Fator reumatóide não foi detectado nesta casuística. Tireoidopatias (seis casos) e artropatias (quatro casos) foram as manifestações clínicas auto-imunes mais observadas. As concentrações de IgM salivar mostraramse elevadas em todos, exceto cinco casos. A comparação dessas concentrações nos grupos com e sem auto-imunidade não mostrou diferença significante (p= 0,48). As conclusões desta pesquisa mostraram os processos infecciosos como as manifestações clínicas mais freqüentes nos pacientes com DIgA, observando-se, porém, uma relevante presença de auto-imunidade nestes pacientes quando reavaliados após a segunda década de vida. Este fato alerta para a necessidade de avaliação rotineira de fenômenos auto- imunes nestes pacientes, durante seguimento. As concentrações de IgM salivar foram semelhantes em pacientes com DIgA com e sem auto-imunidade. Auto-anticorpos foram detectados independentemente da presença de sintomatologia clínica, sendo os mais encontrados aqueles relacionados à tireóide. Os familiares de primeiro grau dos pacientes com DIgA devem ser avaliados, tanto para diagnóstico de imunodeficiências como para detecção de fenômenos auto-imunes, permitindo assim o diagnóstico e abordagens precoces de ambas condições. / IgA deficiency (IgAD) is the most frequent primary immunodeficiency. Its prevalence varies from 1:223 to 1:1000 in epidemiological studies, but in asiatic populations it is uncommon. The clinical manifestations of IgAD are spectral, ranging from asymptomatic patients to recurrent infections, allergic symptoms and/or autoimmunity conditions. The most common infections frequently associated to IgAD involve respiratory and gastrointestinal tracts. The association with other primary immunodeficiency such as common variable immunodeficiency and immunoglobulin G subclasses deficiency has been reported. The aim of this study is to describe clinical and laboratorial evolution regarding autoimmune manifestations in IgAD patients diagnosed during the first years of life and after the second decade and their relatives diagnosed during this study. Laboratorial data included immunoglobulins A and M levels in saliva and auto-antibody screening in immunoglobulin A deficient relatives and patient. The criterion adopted for IgAD diagnosis was defined by Pan-American Group for Immunodeficiency and European Society for Immunodeficiency. The results showed 34 (19 female) immunoglobulin A deficient patients (IgAD) over 10 years of age (range: 10-52 years), 27 of them diagnosed during their childhood, and seven adults detected among 62 screened relatives. Recurrent infections were diagnosed in 91.2% of cases, atopic manifestations in 58.8% and autoimmune clinical manifestation in 52.9%. Autoimmune clinical manifestations were observed in 14 of our 18 IgA deficient patients and relatives with autoimmunity phenomena and seven of them diagnosed only over 10 years old during the study. Auto-antibodies were observed in (10/18) of patients and relatives, with four of them (asymptomatic) showing only the presence of auto-antibodies. Thyroid and osteo-articular involvement (six and four cases, respectively) were the most frequent clinical autoimmune manifestations. The rheumatoid factor was not detected in this casuistic. Auto-antibodies had no statistical difference among patients with or without autoimmunity phenomena. High salivary IgM concentrations were detected in all IgA deficient patients and relatives, except five cases. The comparison of these concentrations in the groups with and without autoimmunity did not show significant difference (p=.0, 48). In conclusion, recurrent infections were the most frequent clinical manifestations of IgA deficient patients and also autoimmune diseases, after the second decade of life. This fact at this series reinforced the necessity of active search for autoimmune conditions diagnosis in these patients. IgM levels showed no statistical difference among IgA deficient patients and relatives with or without autoimmunity. Auto-antibodies, mainly anti-thyroid antibodies, were detected in patients independently of autoimmunity clinical manifestation presence. This study showed the importance of the first degree relatives of IgA deficient patients evaluation, focusing as immunodeficiency as autoimmune disease, permiting an earlier diagnosis of both conditions and an adequate approach to optimize the clinical management and improvement of quality of life of IgAD patients.
120

Host genetic factors and antibody responses with potential involvement in the susceptibility to malaria /

Israelsson, Elisabeth, January 2008 (has links)
Diss. (sammanfattning) Stockholm : Stockholms universitet, 2008. / Härtill 5 uppsatser.

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