Made available in DSpace on 2014-12-17T14:13:51Z (GMT). No. of bitstreams: 1 MariaLSP_DISSERT_1-12.pdf: 307341 bytes, checksum: 501d00488698b866628dca8bc24c0c6e (MD5) Previous issue date: 2010-03-31 / Trata-se de um coorte prospectivo com amostras de leite de 28 m?es da zona rural da Para?ba, durante diferentes dias de amamenta??o exclusiva, com objetivo de avaliar atrav?s do ensaio imunoenzim?tico a presen?a de imunoglobulina A secretora (sIgA) total e espec?fica contra ant?genos de Escherichia coli enteropatog?nica (EPEC) e Shigella flexneri. A reatividade dos anticorpos foi analisada pelo Western blot . Os resultados mostram presen?a da sIgA em todas as amostras, com medianas no colostro de 8,092 g/L(4,546-17,252) e leite de 0,695g/L (0,020-2,830). As medianas nos t?tulos de colostro de IgA anti-EPEC foi 41 (1-659) e anti-Shigella flexneri de 18 (1-4727) enquanto no leite anti-EPEC foi de 8 (1-288) e anti-Shigella flexneri de 6 (1-450). Houve grandes varia??es entre as m?es e entre os dias de amamenta??o. No Western blot os anticorpos sIgA reagiram com prote?nas de EPEC e Shigella flexneri, destacando-se a fra??o antig?nica de 94kDa, correspondente a intimina. Os resultados mostram que a presen?a de sIgA total e de anticorpos IgA contra EPEC e Shigella flexneri no colostro e leite de m?es residentes em zona rural, com prec?rias condi??es s?cioecon?mica e sanit?rias, n?o diferem de estudos realizados com popula??es de ?rea urbana e refor?am a import?ncia do leite materno na defesa contra infec??es ent?ricas. Apesar da aus?ncia na literatura de estudos avaliando o perfil de anticorpos sIgA no leite de m?es residentes em zona rural do Brasil, os resultados demonstraram que a presen?a de sIgA total e de anticorpos IgA contra EPEC e Shigella flexneri no colostro e leite de m?es residentes em zona rural, com prec?rias condi??es s?cio-econ?mica e sanit?rias, n?o diferem de estudos realizados com popula??es de ?rea urbana e refor?am a import?ncia do leite materno na defesa contra infec??es ent?ricas

Orientador: Claudio Lucio Rossi / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-10T14:37:04Z (GMT). No. of bitstreams: 1 Nascimento_FernandaSantos_M.pdf: 1195114 bytes, checksum: 8f7292945661258264c33482af428d55 (MD5) Previous issue date: 2008 / Resumo: A toxoplasmose, uma zoonose com ampla distribuição mundial, causada pelo parasita intracelular obrigatório Toxoplasma gondii, é geralmente adquirida por meio da ingestão de cistos ou oocistos viáveis do parasita, presentes, respectivamente, em carne crua ou mal cozida e no solo, alimento ou água contaminados com fezes de gatos infectados. A toxoplasmose pode ser altamente debilitante, e ocasionalmente fatal, em crianças infectadas no útero e em receptores de transplante. O diagnóstico de infecção aguda primária em mulheres grávidas é geralmente baseado em testes sorológicos, visto que, na grande maioria dos casos, a toxoplasmose não é reconhecida clinicamente. A longa persistência dos anticorpos IgM em algumas pessoas e a dificuldade para demonstrar soroconversão ou aumento significativo da concentração de anticorpos específicos, têm complicado a interpretação dos testes sorológicos, quando se suspeita de infecção aguda. Com relação à infecção toxoplámica em pacientes transplantados, em muitos casos o status sorológico do doador não é conhecido e a pesquisa periódica de anticorpos anti-T. gondii no receptor raramente é realizada. O objetivo do primeiro estudo foi determinar o valor da demonstração dos anticorpos IgA anti-T.gondii para o diagnóstico da fase aguda da infecção toxoplásmica. Nossos resultados mostraram que os anticorpos IgA são detectados com alta freqüência em amostras de soros obtidas de mulheres com evidência clínica e/ou sorológica de infecção toxoplásmica aguda. Entretanto, em 19% das mulheres apresentando persistência de anticorpos IgM e alto índice de avidez dos anticorpos IgG, anticorpos IgA anti-T. gondii foram detectados em amostras de soros coletadas mais de 9 meses após o início da infecção, indicando que esses anticorpos não podem ser considerados marcadores confiáveis de infecção aguda primária. No segundo estudo, nós relatamos o diagnóstico de infecção toxoplásmica primária em um paciente com mieloma múltiplo submetido a transplante alogênico não-mieloablativo de células hematopoiéticas, provenientes de doador com sorologia negativa para toxoplasmose. A resposta primária contra o T. gondii foi baseada na soroconversão dos anticorpos IgM, IgG e IgA. O paciente foi prontamente tratado e nenhuma complicação relacionada à toxoplasmose foi observada nos meses subseqüentes. Esse caso ressalta a necessidade da detecção dos anticorpos anti-T. gondii no doador e no receptor antes do transplante e a importância do monitoramento sorológico do receptor durante o seguimento pós-transplante / Abstract: Toxoplasmosis, a cosmopolitan zoonotic disease caused by the intracellular parasite Toxoplasma gondii, is usually acquired through the ingestion of viable parasite cysts or oocysts, present, respectively, in raw or undercooked meat and in soil, food or water contaminated with feces of infected cats. Toxoplasmosis can be highly debilitating and occasionally fatal in children infected in utero and in transplant recipients. The diagnosis of acute primary infection in pregnant women is usually based on serology, because in the great majority of cases primary infection is not recognized clinically. The sustained persistence, in some persons, of specific IgM antibodies and the difficulty in demonstrating seroconversion or a significant increase in specific antibody concentrations, have complicated the interpretation of serological tests when acute infection is suspected. With regard to toxoplasmic infection in transplant patients, in many cases the serological status of the donor is not known and the periodic research of anti-T. gondii antibodies in the receptor is rarely performed. In the first study, we investigated the usefulness of detecting anti-T. gondii IgA for the diagnosis of an acute acquired Toxoplasma infection. Our results showed that anti-T. gondii IgA antibodies are detected with a high frequency in serum samples obtained from women with clinical and/or serologic evidence of acute acquired Toxoplasma infection. However, in 19% of the women presenting a sustained IgM antibody response and a high IgG avidity index, anti-T. gondii IgA antibodies were detected in serum samples collected more than nine months after the beginning of infection, indicating that IgA cannot be considered a dependable marker for acute primary infection. In the second study, we report the diagnosis of a primary toxoplasmic infection in a patient with multiple myeloma following a non-myeloablative allogeneic transplant with hematopoietic stem cells from a donor with negative serology for toxoplasmosis. The primary response to T. gondii was supported by IgM, IgG and IgA seroconversion. The patient was promptly treated and there were no complications related to toxoplasmosis in the subsequent months. This case stresses the importance of detecting anti-T. gondii antibodies in the donor and in the recipient before transplantation, and of serologically monitoring the recipient during long-term follow-u / Mestrado / Ciencias Biomedicas / Mestre em Ciências Médicas

Submitted by Ramon Santana (ramon.souza@ufpe.br) on 2015-03-10T14:49:55Z No. of bitstreams: 2 Dissertação Viviane Martha de Morais.pdf: 1592021 bytes, checksum: e29a3eec2c8393142f0c5e43344e1535 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) / Made available in DSpace on 2015-03-10T14:49:55Z (GMT). No. of bitstreams: 2 Dissertação Viviane Martha de Morais.pdf: 1592021 bytes, checksum: e29a3eec2c8393142f0c5e43344e1535 (MD5) license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Previous issue date: 2013-02-28 / Introdução: O diagnóstico rápido, simples e preciso para confirmar a infecção pelo vírus dengue (DENV) é uma necessidade real, uma vez que a doença pode se manifestar com um amplo espectro de sinais e sintomas, similares a outros quadros febris agudos. Durante a infecção por dengue se verifica também a produção da imunoglobulina A (IgA) específica, que aumenta ao mesmo tempo que a imunoglobulina M (IgM), permanece positiva por um período de tempo mais curto e se apresenta em níveis mais elevados na infecção secundária. Objetivo: O presente estudo teve como objetivo investigar a presença de IgA no soro durante a infecção primária e secundária (sequencial) pelo DENV. Metodologia: Foram avaliadas amostras de soro por meio do teste imunoenzimático de captura da IgA (AAC-ELISA) in house. Resultados: Avaliou-se um total de 445 amostras de soro, sendo 171 caracterizados como infecção primária e 194 secundária; 40 amostras de indivíduos saudáveis negativos para dengue e 40 de vacinados contra febre amarela. As amostras foram distribuídas em 13 grupos. A positividade da IgA foi de 42,2% (154/365), sendo 27,5% (47/171) na infecção primária e 55,2% (107/194) na secundária. Na infecção secundária, a IgA foi detectada do 2º ao 4º dias de sintomas (grupo 1), antes mesmo da IgM, assim como no grupo 11 no qual a IgM não havia sido detectada (infecção secundária). Na infecção primária o maior valor da sensibilidade foi de 60,0 (36,4 - 80,0) no grupo com 30-35 dias de sintomas e na secundária foi de 87,5% (60,4 – 97,8), grupo com 8 dias de sintomas. A especificidade foi de 100% nas duas infecções (94,3 – 100). Ao aplicar o teste em paralelo para ambas técnicas observou-se um aumento global de 6,6% na sensibilidade do diagnóstico; sendo 2,7% para a infecção primária e de 15,2% para a secundária. A IgA não foi detectada nas amostras dos indivíduos saudáveis, nem nas amostras dos indivíduos recentemente vacinados contra febre amarela. Conclusões: A detecção da IgA demonstrou ser útil como forma de diagnóstico sorológico e em conjunto com a detecção da IgM poderá auxiliar na confirmação de casos agudos de dengue e na interpretação dos resultados de casos inconclusivos, permitindo a adoção de medidas preventivas para evitar a ocorrência de epidemias e ocorrência de casos graves e óbitos.

High training loads or prolonged bouts of acute exercise can increase susceptibility to opportunistic infections. Such infections, although generally medically innocuous, can have profound negative implications for athletic performance. This thesis presents a series of studies investigating which factors influence infection risk in athletes, as well as exploring potential strategies to maintain immunocompetence during heavy training. In Chapters 2 and 3, a large cohort of elite winter endurance athletes were followed over a number of years to determine patterns and frequency of illness in this population, and to identify training- and competition-related predictors of infection. Incidence rates and seasonal patterns of illness were found to be broadly similar to elite athletes from summer sports, and to the general population. Competition, air travel, greater day-to-day fluctuations in training load and lower performance level were significant predictors of illness. When high training loads are combined with insufficient recovery, athletes may become overreached or overtrained. Previous studies suggest that increasing carbohydrate intake can be an effective means of preventing overreaching during periods of intense training. In Chapter 4 we therefore investigated the efficacy of carbohydrate supplementation in reducing immune disturbances and symptoms of overreaching. The lower carbohydrate does (20 g/h during exercise) was found to be equally effective in preserving immunity and power output as the higher dose (60 g/h), with modest immune and performance changes observed in both groups following eight days of intensified training. Many athletes fail to ingest sufficient fluid to maintain euhydration during exercise. However, Chapter 5 found that moderate hypohydration, elicited by a 24 h period of fluid restriction, had little effect on immune responses to prolonged exercise. Altitude training is an important component of the training process of most of today s elite endurance athletes. Chapters 6 and 7 explored the effects of acute and prolonged hypoxic training on immunity. Despite a somewhat augmented stress hormone response to exercise in hypoxia, altitude training was found to have little negative effect on host defence, providing relative exercise intensity at altitude and sea-level was matched.

IgA nephropathy is the world's most common primary glomerulonephropathy. Recent evidence in a rat model implicated excessive production of oxygen-free radicals in the pathogenesis and suggested that vitamin E-treatment ameliorated progression. We studied this antioxidant therapy on the glomerular filtration rate (GFR), proteinuria and hematuria in biopsy-proven IgA nephropathy in children. The duration of treatment or placebo was 2 years, with vitamin E treatment consisting of 400 IU/day in children weighing <30 kg, and twice that dose for those >30 kg. We measured GFR at entry, midpoint and exit. At baseline and at 4-month intervals after randomization, urinary protein/creatinine ratios and urinalysis were examined. The mixed model procedure with log transformation was used in data analysis to test treatment difference as well as the potential time effect. Fifty-five patients were randomized and 38 completed at least 1 year of follow-up. At entry, the clinical characteristics were not different between the treatment and placebo groups. There was a trend toward better preservation of GFR in vitamin E-treated versus placebo patients, 127±50 vs. 112±31 ml/min/1.73 m2, respectively (P=0.09). The urinary protein/creatinine ratio was significantly lower in the vitamin E-treated group vs. placebo; 0.24±0.38 vs. 0.61±1.37 (P<0.013). However, there was no difference in the prevalence of hematuria between the groups. Vitamin E treatment in our study patients was associated with significantly lower proteinuria, but no effect on hematuria. While there was a trend toward stabilization of GFR in the vitamin E-treated patients, longterm treatment and follow-up are needed to determine whether antioxidant therapy is associated with preservation of renal function in IgA nephropathy.

Background Glomerulonephritis is a major cause of end-stage kidney disease (ESRD) in Africa. There is scanty data on the clinico-pathological characteristics and outcome of the mesangioproliferative glomerulonephritides in Africa, despite the non-IgA subtype being reported as a common cause of nephrotic syndrome. This study will assess the outcome of patients with biopsy proven mesangioproliferative glomerulonephritis (MesPGN) from a single centre in Cape Town, South Africa. Methods The study is designed as 10-year retrospective analysis of patients with biopsy proven MesPGN. The MesPGN patterns were divided into non-IgA MesPGN and IgA nephropathy (IgAN), depending on the predominant type of immune deposit. Univariate cox regression analysis was used to determine factors associated with ESRD. Results Data of 109 patients with renal biopsy-proven MesPGN were included for the period between 2005-2014. The mean age at biopsy was 33.8 ±14.9 years, 53.2% were males, and 39.4% were black Africans. Clinically, 58.7% presented with nephrotic syndrome. On histology 79.8% had non-IgA MesPGN, and 20.2% had IgAN. Compared to the non-IgA group, most patients with IgAN were not treated with immunosuppression (72.7% vs. 40.2%; p=0.006). At the last visit, 10.1% reached ESRD (40.9% vs. 2.3%; p<0.0001) and 30.2% achieved complete remission (9.1% vs. 35.7%; p=0.015) for IgAN and non-IgA MesPGN respectively. The 5-year renal survival for IgAN and non-IgA MesPGN respectively, were: 63.3% vs. 97.6%, log rank p=0.001. Overall, hypertension (p=0.019), not receiving immunosuppression (p=0.046) and having IgAN (p=0.007) were independent predictors of progression to ESRD. Conclusion There is a significantly higher ESRD-free survival of patients with biopsy proven non-IgA MesPGN than IgAN. Whether this is related to the limited use of immunosuppressive therapy in IgAN patients or represents a true nature of the disease still requires further research.

京都大学 / 0048 / 新制・課程博士 / 博士(農学) / 甲第19021号 / 農博第2099号 / 新制||農||1030(附属図書館) / 学位論文||H27||N4903(農学部図書室) / 31972 / 京都大学大学院農学研究科応用生物科学専攻 / (主査)教授 久米 新一, 教授 祝前 博明, 教授 廣岡 博之 / 学位規則第4条第1項該当 / Doctor of Agricultural Science / Kyoto University / DFAM

The use of the finite element method within an optimization workflow is fraught with challenges that limit the automation of such workflows. These challenges are inherent to the traditional finite element formulations which are heavily dependent on a manual meshing process that introduces variability that is challenging to account for within an automated workflow. The recently developed flex representation method (FRM) provides a salient solution to the manual meshing process without sacrificing solution accuracy. In response to the development of FRM a global automotive company requested a study to explore the applicability of FRM to one of their sizing-optimization problems: the constrained optimization of a wheel undergoing a rigidity test. In this study we develop an optimization framework based on the DAKOTA optimization framework, the open-source FreeCAD computer-aided design software, and an implementation of FRM within the Coreform IGA solver. Within this framework we demonstrate in the affirmative that FRM enables a highly robust sizing-optimization workflow while requiring minimal effort to prepare the FRM model.

Perturbing gut microbiota early in life can lead to the development of autoimmunity. We are just beginning to unravel how early immune programming by microbiota may have long-term effects on noncommunicable diseases. In this thesis, we lay groundwork for programming of the immune system by commensal bacteria early in life through our studies on the induction of early endogenous neonatal IgA, and we evaluate Limosilactobacillus reuteri's characteristics as an inducer. Garnering attention for use a probiotic, L. reuteri has many proven health promoting benefits, such as IgA induction, but emerging evidence also links specific strains to autoimmune disease. "Super-induction" of neonatal IgA can be achieved through cross-fostering immunocompetent pups on immunocompromised dams. We found that this phenomenon was categorically due to transferal of microbes from dam to offspring. By comparing strain CF48-3A to the non-gastric-related organism L. oris, we discovered that L. reuteri is a microorganism that can enhance early neonatal IgA induction. Further investigations revealed that the ability to induce neonatal IgA is not ubiquitous in all L. reuteri strains, as ATCC PTA 6475 did not significantly elevate IgA. We discovered that 6475 has the antigenic ability to stimulate B cell differentiation and IgA production, but it is suppressed by a mechanism related to differences in surface architecture of this strain. L. reuteri strains also vary in their potency of aryl hydrocarbon receptor (AhR) stimulation. In mice, activation of AhR during gestation by a potent prototypical ligand, TCDD, leads to development of autoimmunity offspring. We found that TCDD exacerbated autoimmunity in adult mice using a strain of mice with similar AhR affinity to humans. Further investigations can clarify whether differential AhR ligand expression between L. reuteri strains contributes to the relationship between L. reuteri and autoimmunity. Overall, we conclude that differences between strains of L. reuteri have profoundly different immunological consequences that contribute to our understanding of the linkage between strains and autoimmunity. / Doctor of Philosophy / Differences in microbes transferred to infants through maternal routes shapes the early development of the immune system. In general, transferred microbes are healthy for the infant, and studies suggest that disruption of healthy microbes in the infant gut is linked to long-term health consequences, like autoimmune diseases. We found that a particular difference in maternally transferred microbes increases the early appearance of immunoglobulin A (IgA, a gut-related antibody) in neonatal mice, which is an antibody important for protecting against gut-related infections. We were able to link this early IgA production to a probiotic species Limosilactobacillus reuteri. Within the species classification as L. reuteri, several genetically different strains are health-promoting and broadly marketed over-the-counter for use in probiotic supplements for infants, children, and pregnant and nursing mothers. Emerging scientific evidence also points to a potential connection between other L. reuteri strains and autoimmune disease. Secreted products of genetically different L. reuteri strains have been discovered to activate aryl hydrocarbon receptor (AhR) with various potency. We used a prototypical AhR ligand and found exacerbation of autoimmune disease in adult mice. Thus, we have concluded that different strains of L. reuteri have broadly different effects on immune system development, and strain variability may explain the different effects on autoimmunity that have been observed.

Expressão aumentada do receptor Fc de IgA (CD89) e da cadeia g associada, avaliadas respectivamente por citometria de fluxo e por “immunobloting", foram encontradas em fagócitos do sangue de pacientes com bacteremia por germes gram-negativos, em comparação com controles e pacientes com bacteremia por gram-positivos. A Mr do CD89 avaliada por SDS-PAGE estava diminuída, com núcleo protéico de 32kDa, sugerindo alteração de glicosilação. O aumento da expressão do CD89 correlacionou-se com aumento dos níveis séricos de IL-6. A cadeia g estava fosforilada nos neutrófilos, sugerindo participação do CD89 na sepsis por gram-negativos. / The expression and function of FcaRI (CD89) were analyzed on blood monocytes and neutrophils of patients with gram-positive and gram-negative bacteremia. Eighteen patients with gram-positive bacteremia, sixteen patients with gram-negative bacteremia and twenty healthy individuals were studied. CD89 expression were analyzed by flow cytometry using specific stained antibodies. Analysis of the surface iodinated CD89 molecules by SDS-PAGE and of the CD89 g-associated chain by immunoblotting also were performed. A marked increase in expression of the a and g subunits of the FcaRI were found on both types of cells in patients with gram-negative bacteremia, but not in patients with gram-positive bacteremia. This increase was independent of serum IgA levels. FcaRI Mr was lower on cells from gram negative patients than on cells from controls (50-65 kDa vs 55-75 kDa) despite of similar 32 kDa backbone, indicating altered glycosylation. Increased levels of FcaRI on blood phagocytes correlated with enhanced serum IL-6 levels, but not with IFN-g or TNF-a levels. The CD89 g-associated chain was phosphorylated on neutrophils, suggesting an engagement of CD89 during gram negative sepsis.