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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.
31

Resposta imune humoral na neurocisticercose / Humoral immune response in neurocysticercosis

Suzuki, Lisandra Akemi 02 October 2010 (has links)
Orientador: Claudio Lucio Rossi / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-15T09:51:57Z (GMT). No. of bitstreams: 1 Suzuki_LisandraAkemi_D.pdf: 1217880 bytes, checksum: 4ceb1f773f112c88145bc69e02976ef2 (MD5) Previous issue date: 2010 / Resumo: A neurocisticercose (NC) e uma importante causa de doença neurológica em muitos paises em desenvolvimento, incluindo o Brasil. O diagnostico clinico da NC e dificultado pelo polimorfismo e pela não especificidade dos sintomas. As tecnicas de neuroimagem e pesquisa de anticorpos específicos tem contribuído para o diagnostico da NC e uma melhor compreensão dos processos fisiopatológicos dessa infecção. O presente trabalho teve como objetivo avaliar, por meio de técnicas imunoenzimaticas (ELISA), a resposta imune humoral na NC, utilizando como preparações antigênicas o liquido vesicular (LV) e uma fração glicoproteica obtida do extrato bruto de cisticercos de Taenia solium (T. solium) com afinidade por lentil-lectina (fração Gp). Cinquenta e seis amostras de liquido cefalorraquidiano (LCR), 22 de pacientes com NC e 34 de pacientes com outros problemas neurológicos, foram utilizadas para a pesquisa de IgG e suas subclasses, com os seguintes resultados: IgG-LV: 100% de sensibilidade e especificidade; IgG1 -LV: 72,73% de sensibilidade e 100% de especificidade; IgG2-LV: 81,81% de sensibilidade e 100% de especificidade; IgG3-LV: 59,09% de sensibilidade e 97,06% de especificidade; IgG4-LV: 90,91% de sensibilidade e 97,06% de especificidade; IgG-fração Gp: 90,91% de sensibilidade e 97,06% de especificidade; IgG1-fração Gp: 59,09% de sensibilidade e 91,18% de especificidade; IgG2-fração Gp: 68,18% de sensibilidade e 94,12% de especificidade; IgG3-fração Gp: 36,36% de sensibilidade e 100% de especificidade; IgG4-fração Gp: 86,36% de sensibilidade e 100% de especificidade. Quarenta e sete amostras de LCR, 16 de pacientes com NC e 31 de pacientes com outros problemas neurológicos foram utilizadas para a pesquisa de IgE, com os seguintes resultados: IgE-LV e IgE-fração Gp: 93,75% de sensibilidade e 100% de especificidade. Cinquenta e sete amostras de soros, 22 de pacientes com NC, 18 de pacientes com outras infecções e 17 de pessoas presumivelmente sadias, foram utilizadas para a pesquisa da IgG e suas subclasses, IgE, IgA e IgM, com os seguintes resultados: IgG-LV: 100% de sensibilidade e especificidade; IgG1-LV: 86,36% de sensibilidade e 94,28% de especificidade; IgG2-LV: 90,91% de sensibilidade e 97,14% de especificidade; IgG3-LV: 86,36% de sensibilidade e 97,14% de especificidade; IgG4-LV: 100% de sensibilidade e de especificidade; IgG-fração Gp: 95,45% de sensibilidade e 100% de especificidade; IgG1-fração Gp: 63,64% de sensibilidade e 94,28% de especificidade; IgG2-fração Gp: 68,18% de sensibilidade e 97,14% de especificidade; IgG3-fração Gp: 54,54% de sensibilidade e 88,57% de especificidade; IgG4-fração Gp: 90,91% de sensibilidade e 100% de especificidade; IgELV: 90,91% de sensibilidade e 97,14% de especificidade; IgE-fração Gp: 86,36% de sensibilidade e 100% de especificidade; IgA-LV: 54,54% de sensibilidade e 94,28% de especificidade; IgA-fração Gp: 13,63% de sensibilidade e 100% de especificidade. Anticorpos IgM não foram detectados com as preparações de LV e fração Gp. Nossos resultados mostraram que, com ambas as preparações antigênicas, tanto em amostras de LCR quanto em amostras de soros, a maior positividade foi obtida na detecção de anticorpos das classes IgG e IgE, seguida da positividade da IgA. Anticorpos IgM não foram detectados em amostras de soros com reações de ELISA realizadas com LV e fração Gp. Com relação as subclasses da IgG, a IgG4 apresentou, tanto em amostras de LCR como em amostras de soros, valores de positividade e concentração iguais ou superiores as outras subclasses. As reações ELISA realizadas com LV mostraram sensibilidades iguais ou superiores aquelas obtidas com a fração Gp. Considerando a complexidade e o custo final da obtenção da fração Gp, o LV pode ser considerado mais adequado para a pesquisa de anticorpos em amostras de LCR e soros de pacientes com NC. / Abstract: Neurocysticercosis (NC) is an important cause of neurological disease in many developing countries, including Brazil. The clinical diagnosis of NC is hindered by the polymorphism and non-specificity of the symptoms. Neuroimaging techniques and detection of specific antibodies have contributed to the diagnosis of NC and a better understanding of the physiopathological processes of this infection. The purpose of this study was to evaluate the humoral immune response in NC by using immunoenzymatic techniques (ELISA) in which vesicular fluid (VF) and a glycoprotein fraction purified from a crude extract of Taenia solium cysticerci with affinity for lentil-lectin (fraction Gp) were used as antigenic preparations. Fifty-six cerebrospinal fluid (CSF) samples, 22 from patients with NC and 34 from patients with other neurological disorders, were assayed for IgG and IgG subclasses, with the following results: IgG-VF: 100% sensitivity and specificity, IgG1 - VF: 72.73% sensitivity and 100% specificity, IgG2 -VF: 81.81% sensitivity and 100% specificity, IgG3 -VF: 59.09% sensitivity and 97.06% specificity, IgG4 -VF: 90.91% sensitivity and 97.06% specificity, IgG-fraction Gp: 90.91% sensitivity and 97.06% specificity, IgG1- fraction Gp: 59.09% sensitivity and 91.18% specificity, IgG2-fraction Gp: 68.18% sensitivity and 94.12% specificity, IgG3 -fraction Gp: 36.36% sensitivity and 100% specificity, IgG4 - fraction Gp: 86.36% sensitivity and 100% specificity. Forty-seven CSF samples, 16 from patients with NC and 31 from patients with other neurological disorders, were assayed for IgE, with the following results: IgE-VF and IgE-fraction Gp: 93.75% sensitivity and 100% specificity. Fifty-seven serum samples, 22 from patients with NC, 18 from patients with other infections and 17 from presumably healthy individuals, were assayed for IgG, IgG subclasses, IgE, IgA and IgM, with the following results: IgG-VF: 100% sensitivity and specificity, IgG1-VF: 86.36% sensitivity and 94.28% specificity, IgG2 -VF: 90.91% sensitivity and 97.14% specificity, IgG3 -VF: 86.36% sensitivity and 97.14% specificity, IgG4 -VF:100% sensitivity and specificity, IgG-fraction Gp: 95.45% sensitivity and 100% specificity, IgG1- fraction Gp: 63.64% sensitivity and 94.28% specificity, IgG2 -fraction Gp: 68.18% sensitivity and 97.14% specificity, IgG3 -fraction Gp: 54.54% sensitivity and 88.57% specificity, IgG4 - fraction Gp: 90.91% sensitivity and 100% specificity, IgE-VF: 90.91% sensitivity and 97.14% specificity, IgE-fraction Gp: 86.36% sensitivity and 100% specificity, IgA-VF: 54.54% sensitivity and 94.28% specificity, IgA-fraction Gp: 13.63% sensitivity and 100% specificity. No specific IgM antibodies were detected with VF and fraction Gp antigenic preparations. These results show that with the two antigenic preparations the highest positivity in CSF and serum samples was obtained for IgG and IgE antibodies, followed by positivity for IgA. No IgM antibodies were detected in serum samples assayed with VF and fraction Gp. With regard to IgG subclasses, IgG4 positivity and concentration in CSF and serum samples were higher than or equal to the other subclasses. ELISA reactions done with VF showed equal or higher sensitivities than those obtained with fraction Gp. Considering the complexity and high cost of obtaining fraction Gp, VF could be more suitable for detecting specific antibodies in CSF and serum samples from patients with NC. / Doutorado / Ciencias Biomedicas / Doutor em Ciências Médicas
32

Rôle de la voie transglutaminase 2/MMP-9 dans la pathogénèse de la néphropathie à IgA et nouvelles approches thérapeutiques / Role of transglutaminase 2 and MMP-9 in the pathogenesis of IgA nephropathy and new therapeutic approaches

Abbad, Lilia 14 September 2018 (has links)
La néphropathie à IgA (IgAN), est une maladie glomérulaire chronique primitive et principale cause d'insuffisance rénale dans le monde. Les causes et les facteurs aboutissant aux dépôts des complexes d'IgA1 sont inconnus. La forme soluble du récepteur (CD89s) complexée aux IgA joue un rôle clé dans la pathogenèse de cette maladie. Actuellement, aucun traitement spécifique n'est disponible et les options thérapeutiques sont limitées. La compréhension des mécanismes de la formation de ces complexes permettra d'envisager de nouvelles approches thérapeutiques. Dans cette perspective la première partie de cette thèse, met en évidence l'implication d'une protéine essentielle au développement de la N-IgA, la TG2, dans la régulation du clivage du CD89, et cela par la répression de la sérine phosphatase PP2A et l'activation de la métalloprotéase matricielle MMP-9. Dans les monocytes de patients l'expression diminuée de PP2A est associée à une tendance à l'augmentation de TG2, et inversement corrélée avec l'augmentation des complexes IgA1-CD89s. Afin de cibler ces complexes pathogéniques, un essai préclinique a été réalisé avec une protéase recombinante d'origine bactérienne clivant spécifiquement les IgA1 (IgA1-P). Les résultats ont formellement démontré la spécificité et l'efficacité de la protéase dans la réduction des complexes circulants et des dépôts d'IgA1 dans le modèle humanisé de N-IgA, associée à une diminution des marqueurs de l'inflammation et de l'hématurie. Les résultats ont mis en évidence le rôle de la dérégulation de l'axe TG2-PP2A-MMP-9 dans la formation des complexes IgA1-CD89s lors de la N-IgA, ainsi que l'efficacité de l'IgA1-P à éliminer ces complexes. Ces travaux suggèrent en plus du potentiel thérapeutique promoteur de l'IgA1-P, trois éventuelles cibles thérapeutiques envisageables pour la N-IgA. / IgA nephropathy (IgAN) is a mesangial proliferative primary glomerulonephritis and a major cause of end-stage renal disease. Causes and factors leading to mesangial IgA1 deposition are unknown. The soluble form of the receptor (sCD89) complexed with IgA plays a key role in the pathogenesis of the disease. There is currently no specific treatment available and the therapeutic options are limited. A better comprehension of the mechanisms regulating the formation of IgA1-sCD89 complexes will unveil new strategies for targeted therapies. In this perspective, the first part of this thesis highlights the implication of the transglutaminase 2 (TG2), a protein essential for the development of IgAN, in the regulation of CD89 cleavage, in a mechanism involving the repression of the serine phosphatase PP2A and the activation of the matrix metalloproteinase MMP-9. While a trend towards TG2 increase is observed, PP2A expression is reduced in monocytes obtained from IgAN patients compared to controls, and inversely correlates with the levels of circulating hIgA1-sCD89 complexes. In order to target these pathogenic complexes, a preclinical assay has been performed with a recombinant protease, a bacterial protein that selectively cleaves human IgA1 (IgA1-P). Results formally demonstrate the specificity and the efficacy of the IgA1-P in the reduction of circulating complexes and mesangial IgA1 deposition in a humanized mouse model of IgAN, associated with a reduction in inflammation and hematuria. Concluding, the results presented in this thesis show a role for the TG2-PP2A-MMP-9 axis in the dysregulated formation of IgA1-sCD89 complexes during IgAN development, as well as the effectiveness of IgA1-P in the elimination of these complexes. In addition to the potential therapeutic use of IgA1-P, this work suggests the TG2-PP2A-MMP-9 axis as a new therapeutic candidate for IgAN treatment.
33

Some observations on Jacalin-Bound proteins and their clinical implication in the investigation of the pathogenesis of IgA Nephropathy.

January 1994 (has links)
To Wah Yuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1994. / Includes bibliographical references (leaves 118-142). / Acknowledgements --- p.1 / Summary --- p.3 / List of Abbreviations --- p.7 / Chapter Part I --- Alpha2-HS glycoprotein: Identification and Characterization of the Jacalin Binding Properties --- p.8 / Chapter Chapter 1 --- Introduction --- p.9 / Chapter 1.1 --- Jackfruit and jacalin --- p.10 / Chapter 1.2 --- Biochemical and immunological properties of jacalin --- p.11 / Chapter 1.2.1 --- Molecular Weight of Jacalin --- p.11 / Chapter 1.2.2 --- Molecular structure of jacalin --- p.11 / Chapter 1.2.3 --- Specificity of jacalin to Thomsen-Fredenreich- antigen (T-antigen) --- p.13 / Chapter 1.2.4 --- The internal repeated sequence in the jacalin --- p.13 / Chapter 1.2.5 --- Jacalin-Bound Proteins (JBP) --- p.15 / Chapter 1.2.6 --- Interaction of jacalin to JBP --- p.15 / Chapter 1.2.7 --- Immunological properties of jacalin --- p.16 / Chapter 1.3 --- Application of jacalin in medical research --- p.17 / Chapter 1.4 --- Background knowledge of α2HSG --- p.18 / Chapter Chapter 2 --- Materials and Methods --- p.20 / Chapter 2.1 --- Design of experiment --- p.21 / Chapter 2.2 --- Identification of the Unknown JBP --- p.21 / Chapter 2.2.1 --- Sera --- p.21 / Chapter 2.2.2 --- Isolation of JBP by Affinity Chromatography --- p.22 / Chapter 2.2.3 --- Fast protein liquid chromatography (FPLC) of JBP --- p.22 / Chapter 2.2.4 --- Affinity chromatography with anti-human IgA column --- p.23 / Chapter 2.2.5 --- Preparation of non-IgA JBP fraction --- p.24 / Chapter 2.2.6 --- N-terminal sequencing of the non-IgA JBP fraction --- p.24 / Chapter 2.2.7 --- SDS-PAGE and immunoblot of gel filtration fractions --- p.25 / Chapter 2.2.8 --- ELISA of FPLC fractions of JBP --- p.26 / Chapter 2.2.9 --- Immunochemical analysis --- p.27 / Chapter 2.3 --- α2HSG: the property of jacalin binding --- p.28 / Chapter 2.3.1 --- α2HSG -jacalin binding curve and competitive ELISA --- p.28 / Chapter 2.3.2 --- Purification of jacalin-crude extract (JCE) --- p.28 / Chapter 2.3.3 --- Characterization of JCE and ASJ --- p.29 / Chapter 2.3.4 --- Comparison of jacalin from different sources for binding to α2HSG by competitive ELISA --- p.29 / Chapter Chapter 3 --- Results --- p.31 / Chapter 3.1 --- Identification of the unknown JBP --- p.32 / Chapter 3.1.1 --- Isolation and FPLC of JBP --- p.32 / Chapter 3.1.2 --- Identification of non-IgA JBP by anti-human IgA affinity column --- p.32 / Chapter 3.1.3 --- Identification of the known JBP in the FPLC fractionated JBP --- p.36 / Chapter 3.1.4 --- Characterization and confirmation of non-IgA JBP --- p.36 / Chapter 3.2 --- α2HSG: the property of jacalin binding --- p.42 / Chapter 3.2.1 --- Characterization of α2HSG-jacalin binding --- p.42 / Chapter 3.2.2 --- Characterization of the purified jacalin --- p.45 / Chapter 3.2.3 --- Comparison of different batches of jacalin to interact with α2HSG --- p.45 / Chapter Chapter 4 --- Discussion --- p.53 / Chapter Part II --- Jacalin-α2HSG binding: the Clinical Values --- p.57 / Chapter Chapter 5 --- Introduction --- p.58 / Chapter Chapter 6 --- Materials and Methods --- p.61 / Chapter 6.1 --- Preparation of IgA-specific jacalin (ASJ) by IgA-Sepharose 4B affinity column --- p.62 / Chapter 6.2 --- Preparation of JCE- and ASJ-Sepharose-4B affinity column --- p.62 / Chapter 6.3 --- Factors affecting the yield of α2HSG --- p.62 / Chapter 6.4 --- Miscellaneous methods --- p.63 / Chapter Chapter 7 --- Results and Discussion --- p.65 / Chapter Part III --- Application of Jacalin for Studying the Pathogenesis of IgA Nephropathy --- p.77 / Chapter Chapter 8 --- An Overview of IgA Nephropathy --- p.78 / Chapter 8.1 --- Clinical manifestation of IgA nephropathy --- p.79 / Chapter 8.2 --- Mesangial deposits in IgAN --- p.80 / Chapter 8.3 --- Human IgA system --- p.81 / Chapter 8.4 --- The role of circulating IgA in the pathogenesis of IgA nephropathy --- p.84 / Chapter 8.5 --- Pathogenesis of primary IgA nephropathy --- p.86 / Chapter 8.6 --- Interaction between circulatory IgA and fibronectin (FN) in primary IgAN --- p.87 / Chapter Chapter 9 --- Materials and Methods --- p.90 / Chapter 9.1 --- Design of experiment --- p.91 / Chapter 9.2 --- Sera --- p.91 / Chapter 9.3 --- Analysis of IgAl/IgA ratio in sera and JBP --- p.91 / Chapter 9.4 --- Purification and Fast protein liquid chromatography (FPLC) of jacalin-bound protein (JBP) --- p.92 / Chapter 9.5 --- Analysis of FPLC-fractionated JBP --- p.93 / Chapter 9.5.1 --- ELISA of IgA-containing immune complexes (IgA-IC) --- p.93 / Chapter 9.5.2 --- "Quantitative ELISA of IgA, K-IgAl, and λ-IgAl" --- p.94 / Chapter 9.5.3 --- "Measurement of sIgA,dIgA and IgA containing immune complex (IgA-IC)" --- p.95 / Chapter 9.5.4 --- SDS-PAGE analysis --- p.95 / Chapter 9.6 --- Statistics --- p.95 / Chapter Chapter 10 --- Results --- p.96 / Chapter 10.1 --- IgA1/IgA ratio of serum and JBP --- p.97 / Chapter 10.2 --- Isolation and FPLC of JBP --- p.97 / Chapter 10.3 --- SDS-PAGE analysis of FPLC fractionated JBP --- p.97 / Chapter 10.4 --- ELISA of the FPLC fractionated JBP --- p.99 / Chapter 10.4.1 --- "Distribution of IgA, secretory IgA (sIgA) and dimeric IgA (dIgA) in the FPLC fractions" --- p.99 / Chapter 10.4.2 --- Distribution of IgA containing immune complex (IgA-IC) in the FPLC fractions --- p.99 / Chapter 10.4.3 --- Quantitation of IgA --- p.106 / Chapter 10.4.4 --- "Quantitation of K-IgAl and λ-IgA1, and determination of k/λ ratio of IgAl" --- p.106 / Chapter 10.4.5 --- "Quantitation of sIgA,dIgA, and IgA-containing immune complex (IgA-IC)" --- p.109 / Chapter Chapter 11 --- Discussion --- p.112 / References --- p.118
34

Ethics of in-game advertisement

Majid, Abdul, Pashaei Rad, Mani January 2012 (has links)
Advergaming is a new type of medium for advertising. It is primarily used by companies targeting children and adolescents. However, there are some ethical issues in Advergaming highlighted by existing scholars. In the primary and secondary studies in this dissertation, it was found that Advergaming comprises deception by positioning simple products (like soft drinks and food) as performance and power stimuli, which is non-compliance against even the basic empirical theories about ethics in advertising. It was also found that companies use the emotions, arousals and stimuli of children to promote their products and also use violent events, unsocial behaviours, negative language, facial expressions, bullying or vindictiveness to make the games more attractive. Companies have also been promoting junk food disguised as power and stimuli enhancers to children. This is very harmful for the children. The study has made recommendations on how parents should deal with this problem and how should they spread the knowledge in the society. The study recommends that the parents should use a permit only policy to choose and permit Advergaming links on computers used by children and adolescents. Moreover, the study also recommends that parents should actively persuade the Advergaming companies to capture their needs and make Advergaming accordingly. For example, the parents can persuade the companies (through their feedback channels) to make educative Advergames. However, the parents should strictly block the Advergames that promote unhealthy eating and drinking habits and harmful behaviours. The parents should spread the knowledge to as many people as they can through personal contacts. / Program: Magisterutbildning i informatik
35

Prevalência de infecções urogenitais durante o trabalho de parto a termo e pré termo e associação com níveis de IgA secretora no colostro / Prevalence of urogenital infections during term and preterm labor and association with secretory IgA levels in colostrums

Araújo, Edilson Dias de 07 November 2018 (has links)
Orientadores: Paulo César Giraldo, Ana Katherine da Silveira Gonçalves / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-11-07T13:39:58Z (GMT). No. of bitstreams: 1 Araujo_EdilsonDiasde_D.pdf: 2801870 bytes, checksum: 056091a8cfb4211f4402aa3462d60140 (MD5) Previous issue date: 2010 / Resumo: As infecções urogenitais (IUG) são muito prevalentes durante a gestação e são reconhecidamente uma das principais causa de trabalho de parto prematuro. Entretanto, a prevalência de IUG no período intraparto é pouco conhecida. Diversas variáveis podem alterar a concentração das imunoglobulinas no colostro. A prematuridade e as infecções urogenitais têm sido estudadas como um destes fatores. Objetivos: Avaliar a prevalência de infecções urogenitais em gestantes durante o trabalho de parto pré-termo e a termo; quantificar os níveis de IgA secretória no colostro de puérperas de parto pré-termo e a termo com e sem infecção urogenital e correlacionar os níveis de IgA secretória nos colostros das puérperas com a presença de infecções urogenitais. Metodologia: No per iodo de janei ro a junho de 2009, 94 gestantes em trabalho de parto, atendidas na Maternidade Escola Januário Cicco (MEJC) da Universidade Federal do Rio Grande do Norte (UFRN), foram alocadas em dois grupos, 49 gestantes em trabalho de parto pré-termo e 45 gestantes em trabalho de parto a termo, foram convidadas a participar do estudo. Para uma melhor homogeneização dos resultados, apenas 34 mães de recém nascidos pré-termo (RNPT) e 38 mães de recém nascidos a termo (RNT), totalizando 72 mães que expressaram colostro no segundo dia de puerpério tiveram seus níveis de IgAs quantificados mediante a utilização de ensaio imunoenzimático (ELISA). Todas as gestantes assinaram o Termo de Consentimento Livre e Esclarecido e passaram por exame ginecológico, quando foi coletado material urinário, vaginal e perianal para estudo microbiológico. Resultados: Nos 94 casos estudados, a prevalência de infecções urogeni tais nas gestantes de parto pré-termo foi d 49,0% e nas gestantes de parto a termo de 53,3% (p=0,8300). Considerando-se os casos de infecções urogenitais, nas gestantes de parto pré-termo e a termo, encontrou-se ITU em 36,7% e 22,2%, candidíase vaginal em 20,4% e 28,9%, vaginose bacteriana em 34,7% e 28,9% e estreptococos do grupo B em 6,1 e 15,6%, respectivamente. Entre as 72 puérperas de recém nascidos de par to prétermo (34) e a termo (38) estudadas, a prevalência de infecções urogenitais nas gestantes de parto pré-termo foi de 50,0% e nas a termo de 52,6%. Considerando-s os casos de infecções urogenitais específicas, nas gestantes de parto pré-termo e a termo, encontraram-se infecção do trato urinário ( ITU) em 32,4% e 15,8%, candidíase vaginal em 17,6% e 26,3%, vaginose bacteriana em 38,2% e 31,6% e estreptococos do grupo B em 5,9% e 15,8%, respectivamente. As concentrações de IgAs foram significativamente mais elevadas no grupo de puérperas de RNPT (1051,3 mg/dL) que no grupo de puérperas de RNT (396,3 mg/dL). Conclusões: Os níveis de IgAs no colostro de mães de RN pré-termo foram significantemente mais elevados que os encontrados em mães de RN a termo. Entretanto apesar da elevada prevalência de diferentes infecções genitais intrapartais, estas não tiveram influência sobre os níveis médios de IgAs, sugerindo que este aumento observado no colostro de mães de RN pré termo esteja relacionado a fatores adaptativos da prematuridade e não a presença das infecções / Abstract: Urogenital Infections (UGI) are very prevalent during pregnancy and are admittedly one of the main causes of premature labor. Still, very little is known about the prevalence of UGI in the intrapartum period. Several variables can change the concentration of immunoglobulins in the colostrum. Prematurity and urogenital infections have been studied as some of these factors. Goal: Assessing the prevalence of urogenital infections in pregnant women during pre-term and fullterm labor; quantifying secretory IgA levels in the colostrum of pre-term and fullterm puerperal women with and without urogenital infection and correlate the levels of secretory IgA levels in the colostrum of pre-term and full-term mothers with urogenital infection. Methodology: 94 pregnant women in labor, who were admitted to Maternidade Escola Januário Cicco - Universidade Federal do Rio Grande do Norte, allocated in two groups, 49 in pre-term labor (PTL) and 45 in full-term labor (FTL), and were invited to participate in the study. For a better homogenization of results, only 72 mothers of PTL (34) and FTL (38) who manifested colostrum on the second day of puerperium had their levels of lgA quantified by immunoassay (ELISA). All these women signed a free and clarified consent term and underwent gynecological examination, when urine, vaginal and perianal samples were collected for microbiological study. Results: In 94 of the cases studied, the prevalence of general infections was 49.0% in the pregnant women in pre-term labor and 53.3% in the pregnant women in full-term labor (p=0.8300). Considering the cases of urogenital infections in both pre-term and full-term pregnant women, Urinary Tract Infection (UTI) was found in 36.7% and 22.2%, as well as Vaginal Candidiasis in 20.4% and 28.9%, Bacterial Vaginosis in 34.7% and 28.9% and Group B Streptococci in 6.1% and 15.6% respectively. Among the 72 PTN (34) and FTN (38) puerperal women studied, the prevalence of urogenital infections was 50.0% in PTN and 52.6% in FTN. Considering the cases of specific urogenital infections, in both PTN and FTN, Urinary Tract Infection (UTI) was found in 32.4% and 15.8%, and Vaginal Candidiasis in 17.6% and 26.3%, Bacterial Vaginosis in 38.2% and 31.6% and Group B Streptococci in in 5.9% and 15.8% respectively. The lgA concentrations were significantly higher in PTN puerperal women (1051.3 mg/dL) than in FTN puerperal women (396.3 mg/dL). Conclusions: The lgA levels in the colostrum of PTN mothers were significantly higher than that found in FTN mothers. However, in spite of the high prevalence of intrapartal genital infections, they did not have influence on the average levels of lgAs, suggesting this increase observed in the colostrum of PTN mothers might be related to adaptive factors of prematurity and not to the presence of infections / Doutorado / Fisiopatologia Ginecológica / Doutor em Ciências da Saúde
36

Avaliação histopatológica e imunológica da mucosa intestinal de aves tratadas com Lactobacillus spp. desfiadas com Salmonella Enteritidis /

Okamoto, Adriano Sakai. January 2005 (has links)
Orientador: Raphael Lucio Andreati Filho / Resumo: Este estudo foi conduzido com o objetivo de avaliar a capacidade protetora de Lactobacillus spp. em frangos de corte desafiados com Salmonella Enteritidis, utilizando-o como tratamento no primeiro dia de idade, e posterior desafio com Salmonella Enteritidis fagotipo 04, observando-se possíveis alterações histopatológicas e imunológicas na mucosa intestinal, como o comprimento das vilosidades, a produção de imunoglobulina A e o peso corporal. Foi observada maior eficácia do tratamento com Lactobacillus spp. somente quando as aves foram desafiadas com Salmonella Enteritidis aos 21 dias de idade. O comprimento das vilosidades intestinais apresentou-se reduzido após os desafios, mostrando posterior regeneração. Com o desafio de Salmonella Enteritidis ocorrendo no terceiro dia de idade, verificou-se que aves jovens possuem maior sensibilidade à infecção. / Abstract: This study was driven with the objective of evaluate the protective capacity of Lactobacillus spp. in chickens challenged with Salmonella Enteritidis, utilizing as handling on one-day old chicks and posterior challenge with Salmonella Enteritidis phagotype 04, observing possible histopathological and immunological alterations in the intestinal mucosa, like the length of the villus, the production of immunoglobulin A and body weight. Greater efficacy in the treatment with Lactobacillus ssp. was observed only when the chicks were challenged with Salmonella Enteritidis at 21 days old. The length of the intestinal villus always diminished after challenge, regenerating later. After the first challenge of with Salmonella Enteritidis (at three-days old), we verified that young chicks possess a greater sensibility to infection. / Mestre
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Particle Gel Immuno Assay (ID-PaGIA) zum Nachweis von anti-IgA Antikörpern

Schönhage, Kai Oliver 30 May 2005 (has links)
Anti-IgA Antikörper werden häufig als Ursache nicht-hämolytischer Transfusionsreaktionen angesehen. Die Inzidenz solcher Reaktionen schwankt zwischen 1:17.000 bis 1:770.000 und beruht größtenteils auf Fallberichten. Die Bedeutung dieser Antikörper, obwohl mit einer Prävalenz von 1: 18 bis 1:1.250 relativ häufig vorkommend, konnte in den circa vierzig Jahren seit ihrer Entdeckung nicht eindeutig geklärt werden; verschiedene Spezifitäten der Antikörper mit unterschiedlichen Reaktionen erschweren die Diagnose und eine klare Schematisierung. Ein Nachteil war bisher das Fehlen einer schnellen und unkomplizierten Nachweismethode, die in vielen Laboratorien angewandt werden kann. Die Ende der sechziger Jahre entwickelte Die Ende der 1960’er Jahre entwickelte Passive Hämagglutination (PHA) ist oft ungenau und unterliegt starken Schwankungen, kann aber relativ einfach durchgeführt werden und ist deshalb die Hauptmethode in der Diagnose von anti-IgA gewesen. Neuere und genauere Methoden wie Radio Immuno Assay (RIA) und Enzyme Linked Immunosorbent Assay (ELISA) sind weder schnell durchzuführen noch in vielen Laboratorien verfügbar. In dieser Arbeit wird eine neue Agglutinationsmethode, Particle Gel Immuno Assay (PaGIA) evaluiert und mit der PHA verglichen. Im ersten Teil wurden die Seren 105 gesunder Spender untersucht: 70 führten zu Reaktionen im PHA mit Titern bis 1:80 während keines im PaGIA reagierte, was die Spezifität des PaGIA unterlegt. Anschließend wurden elf Seren von Patienten mit selektivem IgA Mangel (sDIgA) und 23 Seren von Patienten mit variablem Immundefektsyndrom (CVID) auf das Vorliegen eines anti-IgA Antikörpers untersucht. Fünf Seren beider Patientengruppen führten in beiden Tests zu Agglutinationen und ein Serum (sDIgA) reagierte mit einem Titer von 1:1 in der PHA aber nicht im PaGIA. Die hier gefundenen Prävalenz (22% sDIgA, 45% CVID) und Größe der Titer (sDIgA>CVID) von anti-IgA stimmt mit den bisherigen Erkenntnissen überein. Weitere Untersuchungen konnten die Stabilität des PaGIA bzw. dessen Beads und Reproduzierbarkeit der Ergebnisse über mehrere Monate als auch die Möglichkeit subklassenspezifisches anti-IgA nachzuweisen darlegen. Der PaGIA stellt einen schnell und einfach durchzuführenden Test dar, mit dem anti-IgA Antikörper verschiedener Spezifität verläßlich bestimmt werden können, um Untersuchungen im großen Rahmen durchzuführen, die die Bedeutung der anti-IgA Antikörpern erhellen. / Anti-IgA antibodies are thought to be responsible for non-hemolytic transfusion reactions in one in 17,000 to one in 770,000 number of cases. This incidence is mainly supported by case reports. Despite their relative frequency of one in 18 to one in 1,250, since their discovery approximately forty years ago, the true significance of these antibodies has not yet been determined. Several specificities of these antibodies resulting in different reaction patterns make diagnosis and categorization difficult. Until recently, the lack of a fast and reliable laboratory test was a drawback. This test needed to be easily performed, fast, accurate, reproducible and accessible to many practitioners in many laboratories. The Passive Hemagglutination Assay (PHA), developed in the late 1960’s, is neither precise nor reliable but easy to perform and therefore has been the mainstay in diagnosis of anti-IgA. While newer methods, such as Radio Immuno Assay (RIA) and Enzyme Linked Immunosorbent Assay (ELISA), are neither fast nor easily performed but very precise. This thesis studies and evaluates a new agglutination assay, the Particle Gel Immuno Assay (PaGIA), and compares it to the PHA. In the first part of our study we established the specificity of PaGIA. Sera of 105 healthy blood donors were tested: 70 led to positive reactions with the PHA with titers up to 1:80 while none reacted with the PaGIA. Subsequently, eleven sera of patients with selective deficiency of IgA (sDIgA) and 23 sera of those with Common Variable Immunodeficiency (CVID) were tested for the presence of anti-IgA antibodies. Five sera in each group led to agglutinations in both assays and one serum reacted with a titer of 1:1 in the PHA but not in the PaGIA. The prevalence (22% sDIgA, 45% CVID) and strength of the titers (sDIgA>CVID) of anti-IgA corresponds with current knowledge. Further tests demonstrated the PaGIA’s and its beads stability and reproducibility over several months as well as the possibility for detection of subclass-specific anti-IgA. The PaGIA is a fast and easily performed assay which reliably detects anti-IgA antibodies of different specificities, thereby providing a tool for large scale studies to shed more light on the significance of anti-IgA antibodies.
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Mucosal immunity in the respiratory tract : The role of IgA in protection against intracellular pathogens

Rodríguez, Ariane January 2005 (has links)
<p>The lungs and upper airways are mucosal surfaces that are common site for infection with an enormous variety of inhaled pathogens. Therefore, induction of immune responses in the respiratory tract is crucial for protection against respiratory diseases.</p><p>One of the pathogens infecting the host via the respiratory tract is <i>Mycobacterium Tuberculosis</i>. The reported efficacy of the currently used Bacillus Calmette-Guérin (BCG) vaccine against tuberculosis is highly variable, ranging from 50% against pulmonary tuberculosis to 80% against disseminated tuberculosis. Recently, the current route of vaccination (intradermal) has been considered as a possible factor influencing the protective capacity of the BCG vaccine. In this regard, intradermal route most likely induces protective systemic responses while it fails to induce optimal responses in the lungs. Therefore, our working hypothesis is that vaccination should be directed towards the respiratory mucosal immunity in order to improve the degree of host protection in the lungs.</p><p>In this thesis we studied the effect of the route of immunization as well as of different mucosal adjuvants on the induction of mucosal immune responses against the mycobacterial surface antigen PstS-1. We found that, the intranasal (i.n.) route of immunization was a more favorable route inducing strong local immune responses, than intraperitoneal (i.p.) route. Indeed, i.n. route immunization, unlike the i.p. route, elicited strong IgA responses in the lungs accompanied by a major influx of CD4<sup>+</sup> T cells and a significant local production of IFN-gamma.</p><p>IgA, being the predominant Ig isotype at mucosal tissues, is considered a major effector molecule involved in defense mechanisms against viral and bacterial pathogens at these sites. Therefore, we investigated the possible role of IgA in the protection of the respiratory mucosa against mycobacterial infections, using mice deficient in IgA and in the polymeric Ig receptor. We show that, deficient mice are more susceptible to mycobacterial infections than wild type mice, thereby demonstrating a role for IgA in protection against mycobacteria. Importantly, our studies revealed a reduced production of protective factors, such as INF-gamma and TNF-alpha in the lungs of deficient mice that was associated with the higher susceptibility seen in these mice compared to wild-type mice. We also conducted challenge experiments against another respiratory pathogen, <i>Chlamydia pneumoniae</i>, using IgA deficient mice. Likewise to mycobacteria, our data support a role for IgA in the protection of the respiratory tract against <i>C. pneumoniae</i> infection.</p><p>Finally, we investigated the possible mechanisms explaining the reduced pro-inflammatory responses in IgA deficient mice. Our data indicated that IgA deficient mice present a defective response to stimulation with LPS or 19kDa which appears to be both, essentially due to suboptimal stimulation of macrophages and restricted to the lungs.</p>
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Affibody ligands in immunotechnology applications

Rönnmark, Jenny January 2002 (has links)
This thesis describes the development and use ofnon-immunoglobulin affinity proteins denoted affibodies asalternatives to antibodies in different immunotechnologyapplications. A 58 aa IgG Fc binding three-helix bundle domainZ, derived from staphylococcal protein A has been used asframework for library constructions, in which the face of themolecule involved in the native binding activity has beenengineered by combinatorial protein engineering. Recruting 13surface-located positions for simultanenous substitutionmutagenesis, using degenerated oligonucleotides for libraryassembly at the genetic level, two libraries differing in thechoice of codons were constructed to serve as general sourcesof novel affinity proteins. The libraries were adapted fordisplay onE. colifilamentous phage particles allowingin vitroselection of desired variants capable ofbinding a given target molecule. In selections using human IgAas target, several new IgA specific affibodies could beidentified. One variant ZIgA1, was further investigated and showed binding toboth IgA1 and IgA2 human subclasses as well as to secretoryIgA. This variant was further demonstrated uesful as ligand inaffinity chromatography purification for recovery of IgA fromdifferent samples including unconditioned human plasma.Affibodies of different specificities were also fused to otherprotein domains to construct fusion proteins of relevance forimmunotechnology applications. Using Fc of human IgG as genefusion partner, "artificial antbodies" could be produced inE. colias homodimeic proteins, where the antigenbinding was confered by N-terminally positioned affibodymoieties of different valencies. One area of application forthis type of constructs was demonstrated through specificdetection of the target protein by Western blotting. Exploitingthe uncomplicated structure of affibody affinity proteins, genefusions between affibodies and the homotetrameric reporterenzyme β-galactosidase were constructed, which could beproduced as soluble proteins intracellularly inE. coli. The potential use of such recombinantimmunoconjugates in immunotechnology was demonstrated in ELISAdot-blot and immunohistochemistry, where in the latter case IgAdepositions in the glomeruli of a human kidney biopsy could bespecfically detected with low background staining ofsurrounding tissues. In a novel format for sandwich ELISA, thepossible advantage of the bacterial origin of the affibodyclass of affinity proteins was investigated. As a means tocircumvent problems associated with the presence of humanheterophilic antibodies in serum, causing bakground signals dueto analyte-independent crosslinking of standard capture anddetection antibody reagents, assay formats based oncombinations of antibody and affibody reagents for capture anddetection were investigated and found to be of potentialuse. <b>Keywords:</b>phage display, combinatorial, affinity, IgAligand, immunohistochemistry, affibody-fusions
40

Affibody ligands in immunotechnology applications

Rönnmark, Jenny January 2002 (has links)
<p>This thesis describes the development and use ofnon-immunoglobulin affinity proteins denoted affibodies asalternatives to antibodies in different immunotechnologyapplications. A 58 aa IgG Fc binding three-helix bundle domainZ, derived from staphylococcal protein A has been used asframework for library constructions, in which the face of themolecule involved in the native binding activity has beenengineered by combinatorial protein engineering. Recruting 13surface-located positions for simultanenous substitutionmutagenesis, using degenerated oligonucleotides for libraryassembly at the genetic level, two libraries differing in thechoice of codons were constructed to serve as general sourcesof novel affinity proteins. The libraries were adapted fordisplay on<i>E. coli</i>filamentous phage particles allowing<i>in vitro</i>selection of desired variants capable ofbinding a given target molecule. In selections using human IgAas target, several new IgA specific affibodies could beidentified. One variant Z<sub>IgA1</sub>, was further investigated and showed binding toboth IgA1 and IgA2 human subclasses as well as to secretoryIgA. This variant was further demonstrated uesful as ligand inaffinity chromatography purification for recovery of IgA fromdifferent samples including unconditioned human plasma.Affibodies of different specificities were also fused to otherprotein domains to construct fusion proteins of relevance forimmunotechnology applications. Using Fc of human IgG as genefusion partner, "artificial antbodies" could be produced in<i>E. coli</i>as homodimeic proteins, where the antigenbinding was confered by N-terminally positioned affibodymoieties of different valencies. One area of application forthis type of constructs was demonstrated through specificdetection of the target protein by Western blotting. Exploitingthe uncomplicated structure of affibody affinity proteins, genefusions between affibodies and the homotetrameric reporterenzyme β-galactosidase were constructed, which could beproduced as soluble proteins intracellularly in<i>E. coli</i>. The potential use of such recombinantimmunoconjugates in immunotechnology was demonstrated in ELISAdot-blot and immunohistochemistry, where in the latter case IgAdepositions in the glomeruli of a human kidney biopsy could bespecfically detected with low background staining ofsurrounding tissues. In a novel format for sandwich ELISA, thepossible advantage of the bacterial origin of the affibodyclass of affinity proteins was investigated. As a means tocircumvent problems associated with the presence of humanheterophilic antibodies in serum, causing bakground signals dueto analyte-independent crosslinking of standard capture anddetection antibody reagents, assay formats based oncombinations of antibody and affibody reagents for capture anddetection were investigated and found to be of potentialuse.</p><p><b>Keywords:</b>phage display, combinatorial, affinity, IgAligand, immunohistochemistry, affibody-fusions</p>

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