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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

Immunotoxicity of Dermal Permethrin and Cis-Urocanic Acid: Effects of Chemical Mixtures in Environmental Health

Prater, Mary R. 26 April 2002 (has links)
The present study examined adverse effects of sunlight exposure (mimicked by intradermal cis-urocanic acid, cUCA) on local and systemic immune responses, with or without co-exposure to the immunotoxic insecticide permethrin. A single exposure to cUCA caused diminished splenic macrophage phagocytosis that was persistent up to 30 days post-exposure. Five-day exposure to cUCA subtly increased splenocyte proliferation in response to the T cell mitogen Concanavalin A. Four-week exposure to cUCA caused increased splenic lymphocyte cellularity, thymic hypocellularity, and enhanced hydrogen peroxide production by splenic leukocytes. Single exposure to topical permethrin resulted in decreased thymic and splenic weight and cellularity, and inhibited antibody production by splenic B cells. cUCA worsened the negative effect of permethrin on both thymic weight and cellularity, and depressed splenocyte blastogenesis, hydrogen peroxide production, and antibody production. Five-day exposure to either cUCA or permethrin also caused persistent decreased contact hypersensitivity responses, an effect that became more than additive when the chemicals were administered concurrently. Defects in antigen processing and presentation by cutaneous Langerhans cells were evaluated as possible contributing mechanisms to the cutaneous immunosuppression, using mice with deleted genes. Vehicle-exposed IFNg knockout mice displayed approximately a 22.1% depression in the ear swelling response as compared to control C57BL/6N mice, suggesting that this cytokine may be required for mounting a control-level hypersensitivity response. Ear swelling in cUCA-exposed IFNg knockout mice displayed a 21.4% depressed response as compared to cUCA-exposed wild-type C57BL/6N mice, again suggesting that IFNg is an important cytokine in the contact hypersensitivity (CH) response. TNFaR knockout mice exposed to cUCA displayed 33.9% greater ear swelling than cUCA-exposed wild-type C57BL/6N mice, suggesting that increased TNFa may be involved in inhibited CH by cUCA. TNFaR knockout mice exposed to permethrin displayed 33.9% greater ear swelling than permethrin-exposed C57BL/6N mice, suggesting that increased TNFa may also be involved in inhibited CH by permethrin. C57BL/6N mice exposed to cUCA + permethrin displayed severe reduction of the CH response to 8.7% of the control level. IFNg knockout mice exposed to permethrin + cUCA showed essentially identical depression of the CH response as IFNg knockout mice exposed to either permethrin or cUCA alone. These results suggest that IFNg is required for the greater than additive immunotoxic effect that occurred when these two agents were co-administered. TNFaR knockout mice exposed to cUCA + permethrin displayed 8.7 fold greater ear swelling than similarly exposed C57BL/6N mice, again suggesting that increased TNFa is involved in inhibited CH by both cUCA and permethrin. / Ph. D.
112

Immunomodulatory effects of novel therapies for stroke /

Hall, Aaron A. January 2009 (has links)
Dissertation (Ph.D.)--University of South Florida, 2009. / Includes vita. Includes bibliographical references. Also available online.
113

Le concept de "personnage poétique" dans Les Fleurs du Mal et Le Spleen de Paris de Charles Baudelaire : Fonctions et significations / The concept of "poetic character" in Les Fleurs du Mal and Le Spleen de Paris by Charles Baudelaire : Functions and significations

Saket, Walid 24 October 2014 (has links)
Tenter de cerner le concept de ‘’personnage poétique’’ dans Les Fleurs du Mal et Le Spleen de Paris et essayer d’en déduire les fonctions et les significations, tels sont les objectifs du présent travail. Un processus de conceptualisation fait l’objet de notre première partie qui s’appuie sur les critiques existantes à ce sujet pour donner les statuts adéquats aux êtres peuplant ces deux œuvres. On s’est proposé de voir à travers des exemples précis le traitement que réserve l’œuvre baudelairienne à ce concept, notamment quand il s’agit de passer du poème en vers au poème en prose. Ainsi, des notions limitrophes ont émergé au fil de notre analyse, comme la notion de “figure allégorique” ou “mythique”. Parler de ‘’personnage poétique’’ est donc fort délicat surtout à l’aune de la variation générique qui impose des nuances contraignantes. Mais le fait est là : nous pensons légitime d’attribuer le statut de personnage à certains des sujets qui traversent Les Fleurs du Mal ou Le Spleen de Paris. En effet, ils sont définissables suivant les critères réservés généralement au personnage à savoir, le faire, le dire, la dimension psychologique. Néanmoins, ce statut n’est pas aussi évident quand on constate que dans ces deux œuvres le même sujet peut parfois conjointement relever du traitement de personnage et de figure. Ce travail étant réalisé, notre tâche était d’étudier les fonctions de ces ‘’personnages’’ et de ces ‘’figures’’ dans le cadre de l’esthétique générale de Baudelaire. Dès lors, on a pu voir un processus de dédoublement et de dialogisme se déclencher entre le poète et ses alter ego, qui incarnent ses revendications et ses convictions esthétiques avant-gardistes. / The objectives of the present work are attempting to define the concept of'' poetic character” in'' Les Fleurs du Mal” and” Le Spleen de Paris” as well as trying to deduce the functions and meanings implied in that concept. A process of conceptualization will be our first part .This part will rely on existing critics on this subject to finally give the appropriate statutes to creatures inhabiting these two works. We suggested to study through specific examples the way the works of Baudelaire treat this concept particularly when it comes to moving from free verse poem to prose poem. Thus, adjacent concepts have emerged in the course of our analysis such as the notion of mythical or allegorical figure. Talking about '' poetic character “is so delicate especially in this generic difference that imposes binding shades of meaning. But the fact is that we were able to grant the status of characters to many creatures whether in ‘Les Fleurs du Mal ‘or in ‘Spleen de Paris’. In fact, they can be defined according to the criteria usually reserved to character i.e., do, say, the psychological dimension… However, this status is not that evident when we notice that in these two works the same creature could sometimes jointly be treated as character and figure. Once this work was done, our task was to study the functions of these'' characters'' and '' figures'' in the context of the overall aesthetics of Baudelaire. Consequently, we could see a process of duplication and dialogism between the poet and his creatures. Tackled as his doubles; these creatures embody the poet’s claims and his avant-gardist aesthetic convictions.
114

Quantitative Evaluation of Contrast Agent Dynamics in Liver MRI

Dahlström, Nils January 2010 (has links)
The studies presented here evaluate the biliary, parenchymal and vascular enhancement effects of two T1-shortening liver-specific contrast agents, Gd-BOPTA and Gd-EOB-DTPA, in Magnetic Resonance Imaging (MRI) of healthy subjects and of patients. Ten healthy volunteers were examined with both contrast agents in a 1.5 T MRI system using three-dimensional gradient echo sequences for dynamic imaging until five hours after injection. The enhancement of the common hepatic duct in contrast to the liver parenchyma was analyzed in the first study. This was followed by a study of the image contrasts of the hepatic artery, portal vein and middle hepatic vein versus the liver parenchyma. While Gd-EOB-DTPA gave an earlier and more prolonged enhancement and image contrast of the bile duct, Gd-BOPTA achieved higher maximal enhancement and higher image contrast for all vessels studied during the arterial and portal venous phases. There was no significant difference in the maximal enhancement obtained in the liver parenchyma. In a third study, another 10 healthy volunteers were examined with the same protocol in another 1.5 T MRI system. Using signal normalization and a more quantitative, pharmacokinetic analysis, the hepatocyte-specific uptake of Gd-EOB-DTPA and Gd-BOPTA was calculated. A significant between-subjects correlation of the uptake estimates was found and the ratio of these uptake rates was of the same magnitude as has been reported in pre-clinical studies. The procedure also enabled quantitative analysis of vascular enhancement properties of these agents. Gd-BOPTA was found to give higher vessel-to-liver contrast than Gd-EOB-DTPA when recommended doses were given. In the final study, retrospectively gathered datasets from patients with hepatobiliary disease were analyzed using the quantitative estimation of hepatic uptake of Gd-EOB-DTPA described in the third study. The uptake rate estimate provided significant predictive ability in separating normal from disturbed hepatobiliary function, which is promising for future evaluations of regional and global liver disease. In conclusion, the differing dynamic enhancement profiles of the liver-specific contrast agents presented here can be beneficial in one context and challenging in another. Diseases of the liver and biliary system may affect the vasculature, parenchyma or biliary excretion, or a combination of these. The clinical context in terms of the relative importance of vascular, hepatic parenchymal and biliary processes should therefore determine the contrast agent for each patient and examination. A quantitative approach to analysis of contrast-enhanced liver MRI examinations is feasible and may prove valuable for their interpretation.
115

Células progenitoras CD34+ durante a ampliação esplênica na malária experimental de roedores. / CD34+ progenitor cells during spleen amplification in experimental rodent malaria.

Hermida, Felipe Pessoa de Melo 24 September 2007 (has links)
A malária é uma infecção causada por plasmódios, cujo controle depende do baço, o responsável pelo clareamento dos eritrócitos parasitos. O aumento da parasitemia induz uma ampliação do baço para resolver a infecção, onde participam células precursoras que apresentam CCD34+ na sua superfície. Estudamos a distribuição e a quantidade de células CD34+ em baços de roedores durante malárias de roedores, para compreender sua participação na ampliação do baço e no controle da infecção. Camundongos C57Bl/6j infectados com as cepas AJ e CR de Plasmodium chabaudi, e com a cepa ANKA de Plasmodium berghei, tiveram seus baços removidos e encaminhados para histologia e citometria de fluxo. A distribuição das células CD34+ mostrou-se mais intensa no 4º dia p.i. e menos intensa no 8º dia p.i.. As células CD34+ livres, por citometria de fluxo, surgem com uma onda no 4º dia p.i.. Sua quantidade é similar entre os modelos de P. chabaudi, mas diferente no P. berghei. Neste trabalho, o influxo de células CD34+ no baço não se relaciona com o controle da infecção. / Malaria is caused by Plasmodium sp., which control depends on the spleen, responsible for parasite clearing. The increase of parasitemia implies in spleen amplification to control the infection, with participation of CD34+ cells. We studied the distribution and amount of CD34+ cells in spleen during rodent malaria, to define the role of those cells in spleen amplification and infection control. C57Bl/6j mice were infected with strains CR and AJ of Plasmodium chabaudi, and ANKA strain of Plasmodium berghei. The spleen was removed and processed for histology and flow cytometry. Spleen CD34+ cells was increased in 4th day, p.i., and decreases in 8th day p.i. in all models. By flow cytometry, free CD34+ cells appears as a wave in the 4th day p.i.. P. chabaudi models presented the same level of those cells, which was larger in the P. berghei mice. In this work, increase of spleen CD34+ cells do not correlate with infection control.
116

Papel das células T convencionais e não-convencionais do baço durante a infecção pelo Plasmodium chabaudi AS. / Role of conventional and non-conventional T cell in the spleen during Plasmodium chabaudi AS infection.

Muxel, Sandra Marcia 18 April 2011 (has links)
As células T CD4+ do baço são importantes na proteção frente à malária através de mecanismos mediados pelas citocinas do perfil Th1. Neste trabalho observamos o aumento das células NK1.1+TCR<font face=\"Symbol\">a<font face=\"Symbol\">b por baço nos camundongos C57BL/6, que apresentam o fenótipo de células ativadas, produzem IFN-<font face=\"Symbol\">g, expressam de níveis altos de Fas e PD-L1 que correlaciona com a baixa capacidade proliferativa na fase aguda da infecção pelo Plasmodium chabaudi AS. As células T CD4+ convencionais são a principal subpopulação de células T ativadas na resposta imune frente à infecção, que se desenvolve em duas fases consecutivas concomitantemente com as parasitemias aguda e crônica. Na fase aguda da infecção, a resposta das células T CD4+ convencionais é intensa e de curta duração, com produção grandes quantidades citocinas com cinética semelhante às células T CD4+ não-convencionais. Dessa maneira, as células T CD4+ convencionais possuem um papel central no início da resposta ao P. chabaudi, respondendo em paralelo com as células T não-convencionais como uma ponte entre a imunidade inata e adquirida. / Spleen CD4+ T cells have an important role for protection against malaria through mechanisms mediated by Th1 cytokines. We observed that the increase in NK1.1+TCR<font face=\"Symbol\">a<font face=\"Symbol\">b cell numbers per spleen in C57BL/6 mice, show an activated cell phenotype, with high expression of Fas and PD-L1 correlating with their low proliferative capacity and produce IFN-<font face=\"Symbol\">g during the acute P. chabaudi infection. We show that conventional CD4+ T cells are the main activated T cells subpopulation in the immune response to infection, which develops in two consecutive phases concomitantly with acute and chronic parasitemias. In the acute phase, the conventional CD4+ T cell response is intense and short-lasting, rapidly providing proinflammatory. Taken together, these results indicated the central role of conventional CD4+ T cells during P. chabaudi malaria, acting in parallel with non-conventional CD4+ T cells as a link between innate and acquired immunity.
117

Grotesco e ironia em Macário de Álvares de Azevedo: transgressão, spleen e utopia / Grotesque and inony in Macário of Álvares de Azevedo: transgression, spleen and utopia

Anfora, Adriana Ingrid 17 April 2012 (has links)
Made available in DSpace on 2016-04-28T19:58:45Z (GMT). No. of bitstreams: 1 Adriana Ingrid Anfora.pdf: 629267 bytes, checksum: a904037940bc92d6404af9397dd4f61e (MD5) Previous issue date: 2012-04-17 / This analysis aims to study drama Macário of Álvares de Azevedo, in order to point out each of the concepts of the grotesque, irony and trangression, utopia and spleen, and see how each element composing the text structure azevediana, taking into view of the relationship of antagonistic terms that permeates the opposing aspects of reality and dream, enabling thus a macabre atmosphere, the irruption of the supernatural in terms of imbalances of the man who lives below the dilemma in moral precepts established by society in which he lives or let nature guide their principles and values. The grotesque being investigated in this dissertation in the romantic who seeks, above all, the revolto of the individual against the reality that we can live fully and for that reason, it creates a parallel world that their aspirations to take part in this process / A presente análise tem por objetivo o estudo do drama Macário de Álvares de Azevedo, com o propósito de assinalar cada um dos conceitos relativos ao grotesco, ironia, transgressão, utopia e spleen, e verificar como cada elemento compõe a estrutura textual azevediana, tendo em vista a inter-relação entre esses mesmos componentes. A base fundamental da dissertação será a relação entre termos antagônicos que permearão os aspectos contrapostos do real e do onírico, possibilitando deste modo, uma atmosfera macabra, a irrupção do sobrenatural em função dos desajustes do homem que vive o dilema em seguir preceitos moralmente instituídos pela sociedade na qual vive ou deixar-se então guiar por sua natureza, seus princípios e valores. O grotesco, que está sendo investigado nessa dissertação, é o romântico, que visa, sobretudo, à revolta do indivíduo frente à realidade, que não lhe permite viver plenamente e, por essa razão, acaba criando um mundo paralelo, para que suas aspirações tomem parte em todo esse processo
118

O microquimerismo e a importância das células da medula óssea do doador semi-alogênico na sobrevivência do enxerto. / Microchimerism and the importance of semi-allogeneic donor-derived bone marrow cells in graft survival.

Moraes, Luciana de Deus Vieira de 17 April 2003 (has links)
A indução de tolerância ao enxerto através da administração de células do doador, em períodos que antecedem o transplante, tem se demonstrado eficiente, mesmo em receptores não imunosuprimidos. Os dados da literatura científica são conflitantes quanto ao vínculo entre o microquimerismo e a tolerância aos aloantígenos. No presente estudo, observou-se que a infusão da mistura de células do baço com as da medula óssea, provenientes do doador (BALB/c x C57BI/6)F1, vinte e um dias antes do transplante, resultou em aumento do tempo de sobrevivência dos enxertos de pele e cardíaco, em parentais BALB/c, principalmente quando comparado ao grupo de animais que receberam somente as células do baço do mesmo doador. Assim, procurou-se investigar o estabelecimento do microquimerismo, sua relação com o aumento do tempo de sobrevivência do enxerto e possíveis mecanismos envolvidos. Observou-se um aumento de IL-10 no sobrenadante de cultura das células esplênicas provenientes de animais inoculados com a suspensão mista de células. Em contrapartida, os camundongos que receberam apenas as células do baço apresentaram um aumento da população de linfócitos B. Verificou-se, ainda, que o desenvolvimento de microquimerismo estável não se correlacionou com a tolerância ao enxerto cardíaco, apesar do tempo de sobrevivência do órgão. Esses resultados sugerem que a IL-10 participa no aumento da sobrevida do mesmo quando células do baço com as da medula óssea do doador são administradas antes do transplante. / Tolerance induction to allografts by the administration of donor cells before transplantation has been shown to be efficient, even in non immunosuppressed hosts. There are conflicting reports in the literature regarding the role of microchimerism and tolerance to alloantigens. In the present work, augmentation of skin and cardiac survival time was observed after the infusion of a mixture of donor (BALB/c x C57BI/6)F1 spleen and bone marrow cells twenty-one days before transplantation, specially when compared to donor spleen cell receptors. The establishment of microchimerism, correlation with graft survival time and possible mechanisms involved in this strategy were investigated. An overproduction of IL-10 in the supernatants from spleen cell cultures of mice inoculated with semi-allogeneic cells was observed. Mice that received donor spleen cells only showed increased number of B lymphocytes. Moreover, the establishment of microchimerism did not correlate to tolerance to cardiac allografts despite the augmentation of graft survival time. These results suggest that the development of microchimerism does not prevent graft rejection and that there is a role for IL-10 in graft survival when donor spleen and bone marrow cells are infused before transplantation.
119

Imunidade humoral de camundongos BALB/c e C57BI/6j imunizados com taquizoítos de Toxoplasma gondii irradiados / Humoral immunity in BALB/c and C57Bl/6j mice immunized with irradiated tachyzoite of Toxoplasma gondii.

Zorgi, Nahiara Esteves 03 February 2011 (has links)
Toxoplasma gondii é um agente disseminado com um ciclo de vida complexo que envolve gatos e hospedeiros de sangue quente, incluindo o homem. Componentes vacinais são imunógenos pobres e vacinas atenuadas causam doenças crônicas. Taquizoítos irradiados à 255Gy induzem uma imunidade similar a infecção, com proteção parcial, sem estudos sobre memória. Estudamos a produção de IgG in vitro por células do baço e medula óssea de camundongos imunizados com taquizoítos irradiados e infectados. A medula óssea contém um número maior de células específicas do que o baço. As células de memória são de alta afinidade, mas IgG sérica apresentaram baixa avidez. Há também anticorpos específicos IgA nas fezes. Todas as vacinas indutoras de proteção parcial contra o desafio, que foi mais evidente em alta patogenicidade da cepa ME-49. A proteção foi proporcional tanto à quantidade de anticorpos IgG no soro ou produzidos por células da medula óssea. Nossos dados mostram claramente que os anticorpos de alta afinidade estão relacionados com a sobrevida específica de memória celular. / Toxoplasma gondii is a disseminated agent with a complex life cycle involving cats and warm blood hosts, including man. Component vaccines are poor immunogens and attenuated vaccines cause chronic disease. 255Gy irradiated tachyzoites induce the same immunity as natural infection, with partial protection, without studies on immunological memory. We studied in vitro production of specific IgG by spleen and bone marrow cells of mice immunized with irradiated tachyzoites, comparing with chronically infected animals. Bone marrow contains larger numbers of specific cells than spleen. Memory cells were of high affinity, but serum presented low avidity IgG. We also show presence of specific IgA antibodies in stools. All immunizations induce partial protection against challenge, which was more evident in highly pathogenic ME-49 strain. The protection was proportional both to the amount of IgG antibodies in serum or produced by bone marrow cells. Our data clearly shows that high affinity antibodies are related to specific memory cell survival.
120

Regeneração do autoimplante esplênico em ratos: avaliação morfofuncional e imuno-histoquímica / Splenic autotransplant regeneration in rats: morpholfunctional and immunohistochemical evalution

Valesca Oliveira de Sousa 04 July 2011 (has links)
Diante da importância do baço, deve-se tentar a sua preservação sempre que possível e, nas situações em que a esplenectomia total é inevitável, a única alternativa para a preservação de sua função parece ser a realização do autoimplante esplênico. Neste contexto, o objetivo do presente trabalho foi analisar o desenvolvimento da regeneração morfológica do tecido autoimplantado, sob microscopia de luz e por imunomarcação, e avaliar a regeneração funcional, por meio da depuração dos corpúsculos de Howell-Jolly, em ratos submetidos a esplenectomia total combinada com autoimplante esplênico. Foram utilizados 112 ratos Wistar albinos machos adultos, distribuídos aleatoriamente em 16 grupos. Semanalmente, durante 16 semanas, os sete animais de cada grupo foram submetidos a coleta sanguínea, sendo preparadas lâminas para avaliação da presença de corpúsculos de Howell-Jolly (avaliação funcional), que estiveram presentes durante as 15 primeiras semanas, sendo que, a partir da oitava semana, houve uma diminuição significativa, mas somente não foram mais identificados na 16 semana. Em seguida à coleta sanguínea, os animais correspondentes a cada semana foram mortos por sobredose anestésica e submetidos a relaparotomia para retirada do tecido esplênico autoimplantado regenerado. Posteriormente, esse tecido regenerado foi analisado sob microscopia de luz, onde, sob coloração de hematoxilina-eosina, observou-se regeneração morfológica completa do tecido autoimplantado a partir da oitava semana, sendo encontrado um tecido morfologicamente idêntico ao baço normal. Com a técnica de resorcina-fucsina de Weigert, identificaram-se fibras do sistema elástico, demonstrando elastogênese intensa no processo de regeneração do tecido esplênico autoimplantado. Na imunomarcação com antígeno de proliferação celular nuclear (PCNA), observou-se proliferação celular, evidenciando uma expressão gradativa das células a partir da 2 semana, sendo que, nas 9 e 10 semanas, observou-se aumento significativo na imunodensidade, quando comparadas às demais, o que não ocorreu com a técnica para caspase-3, onde a apoptose mais intensa ocorreu nas primeiras semanas. Nossos resultados mostram que, com oito semanas, existe regeneração morfológica do autoimplante esplênico, assemelhando-se a um baço normal, no mesmo momento em que parece iniciar-se a sua regeneração funcional. / Given the importance of the spleen, it should be preserved whenever possible. If splenectomy is crucial, the only alternative to preserve spleen function is to perform a splenic auto-implantation. The aim of the present study was to assess the morphological regeneration of an auto-implanted spleen and to correlate it to its functional regeneration in a model of splenectomy combined with splenic auto-implantation in rats. Three-month old male Wistar rats (n=112) were randomly allocated into 16 groups (n=7). During 16 weeks, blood was collected to evaluate the presence of Howell-Jolly bodies (functional evaluation). These structures were found during the 15 first weeks, but decreased progressively starting at the 8th week, and were no longer found at the 16th week. In each specific week, after blood collection, rats were killed by anesthetic overdose and subjected to relaparotomy in order to retrieve the regenerated auto-implanted splenic tissue. The tissue was stained by hematoxylin and eosin and analyzed under the light microscope. Full morphological regeneration of the auto-implanted tissue was seen at the 8th week. Intense elastogenesis was detected by the Weigert resorcin-fuchsin stain during regeneration. Cell proliferation was increased starting at the 2nd week, and the highest density was seen at the 9th and 10th weeks (assessed by the immunohistochemistry of the proliferating cell nuclear antigen [PCNA]). Caspase-3 stain indicated higher apoptosis at the first weeks of experiment. The present data show that there is a morphological regeneration of the splenic auto-implant after 8 weeks of implantation, resulting in a morphologically healthy spleen, and it matches the initiation of the functional regeneration.

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