Dissertations / Theses: 'Murids'

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Friberg, Ida Mari. "Macroparasites, immune responses and immunoregulation in wild and laboratory murids." Thesis, University of Nottingham, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.575384.

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This thesis primarily addresses environmental influences, in particular exposure to macroparasite infection, on immunoregulatory expression in wild and laboratory murid rodents. Experimental studies in laboratory mice demonstrated that Heligmosomoides bakeri infection was generally associated with upregulation of systemic toll-like receptor (TLR) expression and TLR-mediated cytokine production at times of peak standing worm burden. TLR function and patterns of expression of TLR and other immunoregulatory genes were also monitored in a time series of wild mice (Apodemus sylvaticus) from a natural population exposed to a range of macroparasites, including Heligmosomoides polygyrus. Differences between wild and laboratory mice in the pattern of coexpression of immunoregulatory and TLR genes and in the transcriptional responses of immunoregulatory genes to TLR-stimulation suggested a stronger regulatory bias in the wild compared to laboratory mice. Perhaps most strikingly, wild mice constitutively express relatively very much more TGF-Bl, TLR2 and TLR4, but not other immunoregulatory genes such as FoxP3, IL-l0 or TNF-a. This indicates that immunoregulatory differences between wild and laboratory mice may be linked to differences in TGF-B1 producing cells, rather than IL-10-producing or FoxP3+ cells. Immunoepidemiological analyses indicated a substantial association of macroparasitic infection (principally due to the louse Polyplax serrata and Heligmosomoides polygyrus) with TLR-mediated cytokine responsiveness in wild mice. Given the primary role of TLRs in anti-bacterial responses, the consistent experimental and epidemiological links between macroparasites and TLRs in this study are interpreted as a possible effect of exposure of the host to bacteria co-localizing in macroparasite infection foci. The identity of genes differentially upregulated in wild vs. laboratory mice might also relate to bacterial exposures (possibly influenced by macroparasite infection, given the associations with TLRs described above?). Thus, TLR2 and TLR4 are key innate anti- bacterial receptors and TGF-B1 is prominently secreted by Th3-type T-regulatory cells which are associated with mucosal tolerance.

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Tyler, Angelia R. "Immigrant Experiences in the United States: The Murids of Senegal in New York." Scholarship @ Claremont, 2011. http://scholarship.claremont.edu/cmc_theses/249.

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This thesis explores West African Muslims in New York as a case study of the immigrant experience in America through discussion of the main theories of assimilation and modes of incorporation into American society. As foreign-born, black Muslims, the Murids of Senegal rely on cohesive social networks to protect themselves from discrimination. This thesis argues that through a process of “segmented assimilation” and reliance on the ethnic enclave, which provides a critical network of support, immigrants like the Murids of Senegal can better manage the challenges they face in the host environment and achieve upward social and economic mobility in urban America while maintaining their cultural identity.

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Sidlar, Katherine. "The role of sciurids and murids in the dispersal of truffle-forming ectomycorrhizal fungi in the Interior Cedar-Hemlock biogeoclimatic zone." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/40418.

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Ectomycorrhizal fungi form an integral tripartite relationship with trees and rodents whereby the fungi provide nutritional benefits for the trees, the trees provide carbohydrate for the fungi, and the rodents feed on the fruit bodies produced by the fungi and then disperse the fungal spores in their feces. When forests are harvested, new ectomycorrhizae must form. It has been assumed that dispersal beyond the root zone of surviving trees happens by way of animals dispersing the spores in their feces, but the importance of particular animal taxa to fungal spore dispersal into disturbed areas in the Interior Cedar Hemlock Biogeoclimatic zone of British Columbia has not previously been investigated. This study observed the occurrence and prevalence of hypogeous fruit bodies (truffles) of ectomycorrhizal fungi, and fungal spores in the feces of a range of rodent species. Truffles were excavated and sciurids (squirrels, chipmunks) and murids (mice, voles) were trapped on sites in a 7 to 102-year chronosequence, as well as unharvested sites adjacent to 7- and 25-year-old sites. The average truffle species richness in soil did not change significantly over the chronosequence. Rhizopogon species were present at all sites and treatments. Deer mice (Peromyscus maniculatus) and yellow-pine chipmunks (Tamias amoenus) were the most commonly trapped rodents across all site ages and were also the most likely to move between harvested and unharvested areas. Red-backed voles (Clethrionomys gapperi), red squirrels (Tamiasciurus hudsonicus), and flying squirrels (Glaucomys sabrinus) were also studied, but were trapped in much lower numbers and rarely, if ever, were detected moving between harvested and adjacent mature sites. However, all animal taxa studied carried fungal spores in their feces. Spores of Rhizopogon spp. and Hysterangium separabile were the most frequently consumed by all the animals studied. Because deer mice and chipmunks were the most likely to move between mature and harvested sites and they frequently carried fungal spores in their feces, they are likely the most important mammals for dispersal of ectomycorrhizal fungal spores in this area. This study highlights the importance of small mammal conservation when forest management is considered.

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de, la Fuente Hernández Noa. "Generación de modelos murinos de adenocarcinoma pancreático con mayor eficiencia metastásica para el estudio de agentes antitumorales." Doctoral thesis, Universitat Autònoma de Barcelona, 2021. http://hdl.handle.net/10803/673338.

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L’ adenocarcinoma ductal de pàncrees (ACDP) és un tumor agressiu, de biologia tumoral i genètica complexa, amb mal pronòstic per el seu diagnòstic tardà i quimioresistència. El receptor de quimiocines, CXCR4 és un marcador de cèl·lules mare tumorals metastàtiques, associat amb un augment de la invasió, la disseminació tumoral i la quimioresistència en tumors pancreàtics. Aquest receptor seria, per tant, una diana excel·lent per al adreçament d’una teràpia antitumoral i antimetastática. La motivació per a la realització d’aquest projecte de tesi ha estat la necessitat de desenvolupar treballs de recerca per millorar el diagnòstic, el pronòstic i el tractament de l’ACDP. En aquest treball s’han generat models en ratolí amb una major eficiència metastàtica que permeten ampliar l’estudi d’aquesta patologia i que s’han utilitzat, a més, per validar dos tractaments de l’àmbit de la nanomedicina: una membrana constituïda per nanofibres que permet un alliberament local i controlada de fàrmac cap al tumor primari i una nanopartícula per al lliurament dirigida d’un citotòxic cap a les cèl·lules mare tumorals CXCR4+, implicades en el procés de metàstasi. Els objectius específics d’aquest projecte han estat: l’obtenció de mostres de ACDP humà i l’estudi de l’expressió de CXCR4; la creació de models en ratolí de ACDP d’alta eficiència metastàtica a partir de línies cel·lulars de ACDP i mostres tumorals humanes amb alta expressió de CXCR4; l’avaluació, en xenógrafs ortotòpics pancreàtics, de l’eficàcia terapèutica d’una membrana de nanofibres produïda per la polimerització d’àcid poli (làctic-co-glicòlic, PLGA) i carregada en la seva matriu amb el citotòxic SN38 (CEB-01-SN38 ) en tractament únic o en combinació amb quimioteràpia, i finalment, l’estudi de la citotoxicitat i biodistribució in vivo de la nanopartícula T22-O-Gemcitabina (T22-O-GEM), adreçada a l’eliminació selectiva de les cèl·lules mare metastàtiques.Per a això, la metodologia ha inclòs experiments in vitro (cultiu cel·lular i l’obtenció de línies tumorals PANC-1 i MIA PaCa-2 amb expressió de CXCR4 i l’obtenció d’una línia tumoral a partir d’un tumor de ACDP de pacient), i experiments in vivo (la generació de models subcutanis de ADCP i models ortotòpics metastàtics, la implantació de membranes CEB-01, l’administració de quimioteràpia, el seguiment de l’ creixement tumoral i avaluació de les metàstasis per bioluminescència), i finalment, l’avaluació de la citotoxicitat i biodistribució in vivo de T22-GFP-GEM. Les nostres conclusions són que la implantació de cèl·lules tumorals amb sobreexpressió de CXCR4 augmenta significativament la disseminació tumoral i és útil per a l’avaluació preclínica d’ antitumorals, que la implantació ortotòpica de biòpsies humanes amb alta expressió de CXCR4 és un model més predictiu per a la clínica, que la implantació de la membrana CEB-01 amb SN-38 permet el control de l’ creixement tumoral local i la seva combinació amb quimioteràpia pot controlar la progressió tumoral i disminuir la càrrega tumoral metastàtica, i que la nanopartícula T22-O-GEM presenta adreçament cap a cèl·lules mare tumorals metastàtiques i indueix mort cel·lular. Aquest tractament podria aconseguir un major efecte antitumoral comparat amb el tractament estàndard amb Gemcitabina, disminuint, a més, la toxicitat depenent de dosi.
El adenocarcinoma ductal de páncreas (ACDP) es un tumor agresivo, de biología tumoral y genética compleja. Presenta un mal pronóstico por su diagnóstico tardío y quimiorresistencia. El receptor de quimiocinas, CXCR4 es un marcador de células madre tumorales metastásicas. Varios estudios lo han asociado con un aumento de la invasión, la diseminación tumoral y la quimiorresistencia en tumores pancreáticos. Este receptor sería, por tanto, una diana excelente para el direccionamiento de una terapia antitumoral y antimetastásica. La motivación para la realización de este proyecto de tesis ha sido la necesidad de desarrollar trabajos de investigación que permitan encontrar nuevas herramientas para mejorar el diagnóstico, el pronóstico y el tratamiento del ACDP. En este trabajo se han generado modelos en ratón con una mayor eficiencia metastásica que permiten ampliar el estudio de esta patología. Estos modelos se han utilizado, además, para validar dos tratamientos del ámbito de la nanomedicina: una membrana constituída por nanofibras que permite una liberación local y controlada de fármaco en el tumor primario tras la resección quirúrgica, y una nanopartícula para la entrega dirigida de un citotóxico hacia las células madre tumorales CXCR4+, implicadas en el proceso de metástasis, permitiendo, en ambas estrategias, un aumento de la concentración farmacológica del compuesto antitumoral, y disminuyendo la toxicidad sistémica asociada al tratamiento. Los objetivos específicos de este proyecto han sido: la obtención de muestras de ACDP humano y el estudio de la expresión de CXCR4; la creación de modelos en ratón de ACDP de alta eficiencia metastásica a partir de líneas celulares de ACDP y muestras tumorales humanas con alta expresión de CXCR4; la evaluación, en xenógrafos ortotópicos pancreáticos, de la eficacia terapéutica de una membrana de nanofibras producida por la polimerización de ácido poli (láctico-co-glicólico, PLGA) y cargada en su matriz con el citotóxico SN-38 (CEB-01-SN38) en tratamiento único o en combinación con quimioterapia,y finalmente, el estudio de la citotoxicidad y biodistribución in vivo de la nanopartícula T22-O-Gemcitabina (T22-O-GEM), dirigida a la eliminación selectiva de las células madre metastásicas. Para ello, la metodología ha incluido experimentos in vitro (cultivo celular y la obtención de líneas tumorales PANC-1 y MIA PaCa-2 con expresión de CXCR4 y la obtención de una línea tumoral a partir de un tumor de ACDP de paciente), y experimentos in vivo: la generación de modelos subcutáneos de ADCP y modelos ortotópicos metastásicos, la implantación de membranas CEB-01, la administración de quimioterapia, el seguimiento del crecimiento tumoral y evaluación de las metástasis por bioluminiscencia), y finalmente, la evaluación de la citotoxicidad y biodistribución in vivo de T22-GFP-Gemcitabina y el análisis de la expresión de CXCR4 en muestras de pacientes con ACDP. Nuestras conclusiones son que la implantación de células tumorales con sobreexpresión de CXCR4 aumenta significativamente la diseminación tumoral y es útil para la evaluación preclínica de compuestos antitumorales, que la implantación ortotópica de biopsias humanas con alta expresión de CXCR4 es un modelo más predictivo para la clínica, que la implantación de la membrana CEB-01 cargada con el fármaco SN-38 permite el control del crecimiento tumoral local y su combinación con quimioterapia puede controlar la progresión tumoral y disminuir la carga tumoral metastásica, y que la nanopartícula T22-O-GEM presenta direccionamiento hacia células madre tumorales metastásicas e induce muerte celular. Este tratamiento podría conseguir un mayor efecto antitumoral comparado con el tratamiento estándar con Gemcitabina, disminuyendo, además, la toxicidad dependiente de dosis observada en los quimioterápicos utilizados habitualmente, no sólo en ACDP sino en otras neoplasias.
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive neoplasia with a complex tumor behaviour and genetics. It has a poor prognosis due to its late diagnosis and chemo- resistance. CXCR4, a marker of metastatic tumor stem cells, has been associated with an increase in invasion, tumor spread and chemoresistance in pancreatic tumors. This receptor could be a good target for the addressing of an anti-tumor and antimetastatic therapy. The motivation to perform this thesis has been the need to develop research work that will allow to find new tools that improve the diagnosis, prognosis and treatment of PDAC. In this work, mouse models have been generated with greater metastatic efficiency to expand the study of this pathology. They have also been used to validate two treatments in the field of nanomedicine, which allow a local controlled release of the drug in the primary tumor after surgical resection, and targeted administration of cytotoxic to CXCR4+ tumor stem cells, associated with metastasis, allowing an increase in pharmacological concentration and decreasing systemic toxicity. The specific objectives of this project have been to obtain samples from human PDAC and to study the expression of CXCR4, the development of high-efficiency metastatic mouse models of PDAC from PDAC cell lines and human tumor samples CXCR4+. Those models were used to evaluate the therapeutic efficacy of a nanofiber membrane produced by poly acid polymerization (lactic-co-glycolic) loaded with cytotoxic SN-38 (CEB-01-SN38) and treated alone or in combination with chemotherapy, and the study of in vivo cytotoxicity and biodistribution of the nanoparticle T22-O-Gemcitabine (T22-O-GEM), aimed at selective elimination of metastatic stem cells. To this end, the methodology has included conducting in vitro experiments: cell culture and obtaining PANC-1 and MIA PaCa-2 tumor lines with high CXCR4 expression and a tumor line from a patient's PDAC tumor, as well as in vivo experiments developing subcutaneous PDAC models and metastatic orthotopic models, implantation of CEB-01 membranes, administration of chemotherapy, monitoring of tumor growth and determination of metastases by bioluminescence, and finally, the evaluation of cytotoxicity and in vivo biodistribution of T22-GFP—GEM. Our conclusions are that implantation of tumor cells with CXCR4 overexpression significantly increases tumor spread being usefulness for preclinical evaluation of antitumor compounds. The orthotopic implantation of human biopsies with high expression of CXCR4 is a more predictive and translational model for preclinical assays. The implantation of the CEB-01 membrane loaded with the drug SN-38, can control the local tumor growth alone or combined with chemotherapy, decreasing metastatic tumor spread, and finally, the T22-O-GEM nanoparticle could be used to eliminate metastatic cancer stem cells and it might induce greater antitumor effects than the standard treatment with Gemcitabine, reducing the side effects of standard chemotheratic treatments.
Universitat Autònoma de Barcelona. Programa de Doctorat en Cirurgia i Ciències Morfològiques

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Shears, Rebecca. "Defining the host protective antigens secreted by the murine whipworm, Trichuris muris." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/defining-the-host-protective-antigens-secreted-by-the-murine-whipworm-trichuris-muris(34417c03-44c9-46ff-bae8-9509f4c74e1c).html.

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Soil-transmitted helminths are a major cause of morbidity for humans and their livestock. A combination of better sanitation, anthelminthic drugs and vaccines are predicted to reduce the morbidity of these parasites in humans. The drugs currently used to treat these infections, albendazole and mebendazole, are fairly ineffective against Trichuris trichiura (human whipworm), and there are reports of drug resistance arising within parasite populations in Vietnam and Zanzibar. There are also no commercially available vaccines against human STH species, and very few against their veterinary counterparts. The murine whipworm, T. muris, has been used for over 50 years as a model for T. trichiura. These parasites share homology at the genomic and transcriptomic levels, and the immune responses associated with both acute and chronic infection have been well studied using the T. muris mouse model. T. muris excretory/secretory products have been studied in the context of vaccination for over four decades, however relatively little progress has been made towards identifying the molecular components that stimulate protective immunity following vaccination or during acute infection. Here, a stringent selection protocol was developed using chromatography and mass spectrometry methods combined with a measurement of T cell cytokine production. The work presented in this thesis provides a novel framework for identifying potential immunogenic candidates within adult T.muris excretory/secretory products. Exosome-like vesicles isolated from adult T. muris ES were also explored as a source of host protective material. Vaccination with exosome-like vesicles protected male C57BL/6 mice from a subsequent low dose infection, which would ordinarily progress to chronicity, and a number of potential immunogenic candidates were identified. Over the course of this thesis, several important observations were made relating to characteristics of the immune response induced by vaccination with ES. Firstly, proteinaceous material is likely to be responsible for the host protective properties of ES. Secondly, vaccination with ES products stimulates long-lasting immunity. Thirdly, vaccination with ES collected from both larval and adult stages stimulates protective immunity. The number of potential immunogenic candidates has also been narrowed down from over four hundred to just eleven. Given the homology between T. muris and T. trichiura at both the genomic and transcriptomic levels, this work has the potential to advance vaccine design for T. trichiura and other Trichuris parasites.

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Bastos, Rosidete Pereira. "Infecção murina por isolados de Leishmania (Viannia) braziliensis: avaliação da participação de leucotrienos endógenos." Universidade Federal de Goiás, 2008. http://repositorio.bc.ufg.br/tede/handle/tede/4187.

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The knowledge about immunology of Leishmania (Viannia) braziliensis-murine infection is poorly known, especially concerning innate immune response and the involvement of leukotrienes in the resistance mechanisms. Leukotrienes are lipid mediators of inflammation that activate microbicidal mechanisms in leukocytes. The present study aimed to evaluate the BALB/c and C57Bl/6 murine infection with two L. (V.) braziliensis isolates obtained from cutaneous leishmaniasis patients and the involvement of leukotrienes in the resistance of infection. Thus, IMG3 and RPL5 isolates were identified as L. (V.) braziliensis by using molecular techniques and the in vitro growth of parasites in Grace´s medium (26°C) was evaluated. The time course of lesion after footpad infection was followed in BALB/c and C57Bl/6 mice. C57Bl/6 mice genetically deficient in interferon gamma (IFNγ) were infected to evaluate the relevance of this cytokine in resistance. The parasite burden in draining lymph nodes and spleens was detected by limiting dilution assay. BALB/c- and C57Bl/6-infected footpads were processed after 12 weeks of infection and those from IFNγ-defecient mice after 4 weeks for histopathological analyses. Tissue sections were stained by hematoxylin-eosin. Parasite capacity to induce nitric oxide (NO) was analyzed in RAW 264.7 cell cultures treated or not with IFNγ and lipopolysaccharide (LPS). Nitrites were detected by using Griess reaction. The NO modulation by endogenous leukotrienes was evaluated through treatment of the cultures with a 5-lipoxygenase (5-LO) inhibitor and a leukotriene B4 (LTB4) antagonist. Macrophage leishmanicidal activity against IMG3 isolate was evaluated in thioglycolateelicited peritoneal macrophages of C57Bl/6 mice. In these cultures, NO was inhibited by aminoguanidine. In vivo leukotriene inhibition was achieved by using a 5-LO inhibitor. In vitro-parasite growth profiles were similar and parasites at the 5th day of culture were used to infection. The lesion course was also similar between isolates in both two mouse stains used, but C57Bl/6 mice presented healing after 12 weeks of infection whereas in BALB/c mice the lesion was persistent. In IFNγ-deficient mice there progressive lesions and visceralization in IMG3- as well as in RPL5-infected mice. Corroborating these data, the parasite burden in draining lymph nodes of BALB/c mice was higher than in C57Bl/6 mice after 12 weeks of infection with IMG3, and parasites (IMG3 and RPL5) were identified in about 50% of the IFNγ-deficient mouse spleens. The histopathological analyses showed an intense dermal infiltrate with vacuolated macrophages heavily parasitized in BALB/c mice (12 weeks) an in IFNγ-deficient mice (4 weeks), but not in C57Bl/6 mice (12 weeks), similarly for IMG3 and RPL5. Both isolates IMG3 an RPL5 induced NO production in RAW 264.7 celll cultures presenting synergism with IFNγ. Endogenous leukotrienes did not affect NO production in these cultures. C57Bl/6 peritoneal macrophages activated with IFNγ/LPS killed IMG3 parasites depending on NO release. In vivo inhibition of leukotriene synthesis did not change the course of infection in C57Bl/6 mice infected with IMG3 isolate. The relevant findings are: BALB/c mouse is susceptible to infection with IMG3 an RPL5 isolates whereas C57Bl/6 is resistant; IFNγ is crucial to the control of the infection; the isolates induce NO and this molecule contributes to macrophage leishmanicidal activity; and also the data suggest that endogenous leukotrienes are not involved in the control of L. (V.) braziliensis in C576Bl/6 mouse.
A imunologia da infecção murina por Leishmaia (Viannia) braziliensis é pouco conhecida, especialmente considerando a imunidade inata e a participação dos leucotrienos nos mecanismos de resistência à infecção. Os leucotrienos são mediadores lipídicos da inflamação que ativam mecanismos microbicidas dos leucócitos. O presente trabalho teve como objetivo avaliar o perfil da infecção de camundongos BALB/c e C57Bl/6 por dois isolados de L. (V.) braziliensis obtidos de pacientes com leishmaniose cutânea e o envolvimento dos leucotrienos endógenos na resistência à infecção. Para isto, os isolados denominados IMG3 e RPL5 foram identificados como L. (V.) braziliensis por meio de técnicas moleculares e foram avaliados quanto ao crescimento in vitro em meio Grace (26°C), e quanto ao curso da evolução da lesão, em camundongos BALB/c e em C57Bl/6. Camundongos C57Bl/6 geneticamente deficientes em interferon gama (IFNγ) foram infectados para avaliar a importância desta citocina no controle da infecção. A carga parasitária foi obtida pelo ensaio da diluição limitante em linfonodos drenantes da lesão e nos baços. As patas dos camundongos BALB/c e C57Bl/6 foram colhidas após 12 semanas de infecção, e dos camundongos deficientes em IFNγ, na 4ª semana, e foram processadas para análises hitopatológicas. A capacidade de indução de óxido nítrico (NO) pelos isolados foi avaliada em culturas de células RAW 264.7 tratadas ou não com IFNγ e lipopolissacarídeo (LPS), sendo os nitritos detectados por reação de Griess. A regulação da produção de NO pelos leucotrienos endógenos foi avaliada por tratamento das culturas de macrófagos com um inibidor de 5-lipoxigenase (5-LO) e um antagonista de receptor de leucotrieno B4 (LTB4). A atividade microbicida dos macrófagos foi avaliada em macrófagos peritoneais (C57Bl/6) infectados com o isolado IMG3, sendo o NO inibido por aminoguanidina. O efeito da inibição de leucotrienos, in vivo, foi avaliado em camundongos C57Bl/6 infectados com o isolado IMG3 e tratados com um inibidor de 5- LO. As curvas de crescimento in vitro foram similares para os dois isolados e os parasitos no 5° dia de cultivo foram usados nos experimentos de infecção. O curso da lesão foi similar entre os dois isolados nos camundongos BALB/c e C57Bl/6, porém enquanto a lesão regrediu nos C57Bl/6, nos camundongos BALB/c, a lesão foi persistente até a 12ª semana de infecção. Em camundongos deficientes em IFNγ houve crescimento progressivo das lesões e visceralização, tanto com o isolado IMG3 quanto com o RPL5. Confirmando estes dados, a carga parasitária nos linfonodos drenantes da lesão nos camundongos BALB/c foi maior do que a encontrada nos C57Bl/6 após 12 semanas de infecção com IMG3 e os parasitos (IMG3 e RPL5) foram encontrados em cerca de 50% dos baços dos camundongos deficientes em IFNγ. As análises histopatológicas mostraram um acentuado infiltrado inflamatório na derme, com macrófagos vacuolizados repletos de parasitos nos camundongos BALB/c (12 semanas), e nos deficientes de IFNγ (4 semanas), mas não nos camundongos C57Bl/6 (12 semanas), similarmente para IMG3 e RPL5. Os isolados IMG3 e RPL5 induziram NO em células RAW 264.7 em sinergismo com IFNγ e os leucotrienos endógenos não alteraram a produção de NO destas células. Macrófagos peritoneais murinos mostraram atividade microbicida de maneira dependente de NO. A inibição in vivo da síntese de leucotrienos não alterou o curso da infecção pelo isolado IMG3 em camundongos C57Bl/6. Coletivamente, os dados mostram que o camundongo BALB/c é suscetível à infecção pelos dois isolados, enquanto o C57Bl/6 é resistente; o IFNγ é essencial para o controle da infecção; os isolados induzem a produção de NO, o qual contribui para a eliminação dos parasitos; e os dados sugerem que os leucotrienos endógenos não estão envolvidos nos mecanismos de resistência dos camundongos C57Bl/6 a L. (V.) braziliensis.

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Rodrigues, Raquel Ferreira. "Estudo dos compostos mesoiônicos tiadiazólicos contra Leishmania sp e inibição da tripanotiona redutase." reponame:Repositório Institucional da FIOCRUZ, 2011. https://www.arca.fiocruz.br/handle/icict/4275.

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Fundação Oswaldo Cruz. Instituto de Comunicação e Informação Cientifica e Tecnológica em Saúde. Rio de Janeiro, RJ, Brasil.
A leishmaniose é uma das principais doenças parasitárias com prioridades de pesquisa segundo a Organização Mundial da Saúde. Aurgência por drogas mais seletivas e menos tóxicas tenm conduzido a pesquisa por novas terapias químicas. Os compostos mesoiônicos (Mls) da classe 1,3,2 - tiadiazol-2-aminida, apresentam um amplo espectro de atividades biológica, incluindo efeitos antitumoral e leishmanicida. Neste estudo investigamos a atividade in vitro de Ml-HH, Ml-4-NO2, Ml-3OCH3 e Ml-4-OCH3 sobre promastigotas e amastigotas axênicas de L. infantum e amastigotas intracelulares de L. infantum e L. amazonensis. Uma alta atividade leishmanicida foi demonstrada contra L. infantum e constatou-se uma relação de dose-resposta para formas amastigotas intracelulares de L. infantum e L. amazonensis pelo Ml-4-NO2. Em etapa seguinte investigamos in vivo o efeito de Mls nos seguintes modelos camundongo/parasito: CBA/J e L. amazonensis, BALB/c e L. amazonensis e BALB/c e L. infantum. No primeiro modelo, a administração por via subcutânea de Ml-HH e Ml-4-OCH3 levou a uma diminuição da carga parasitária no linfonodo adjacente à lesão e no baço. Nos dois modelos seguintes, altamente sensíveis à infecção, foram estudados Ml-HH, Ml-4-NO2, avaliando além de parâmetros daresposta terapêutica e tóxicos, possíveis efeitos imunomoduladores. Camundongos susceptíveis da linhagem BALB/c foram infectados por via subcutânea na pata com promastigotas de L. amazonensis e viaintraperitonal por L. infantum. Os tratamentos utilizados foram por vias tópica, intralesional para leishmaniose cutâna (LC) e intraperitoneal para leishmaniose visceral (LV). Glucantime, droga anti-Leishmania clássica, foi utilizada como referência. Embora a cura completa não tenha sido observada nos animais com LC, os grupos tratados com Ml-4 - NO2 e Ml-4-OCH3 apresentaram pequenas lesões na pata infectada até 12ª semana após a infecção sem apresentar ulcerações. Ogrupo LV tratado com Ml-4-NO2 apresentou carga parasitária negativa no baçço e no fígado. O tratamento de LV com Glucantime e Ml-4-OCH3 reduziu de forma significativa a carga parasitária. Porém o tratamento com Ml-HH, em todas as vias utilizadas, não apresentou atividade terapêutica para LC ou LV. A avaliação de enzimas hepáticas (AST e ALT) e de creatinina apontam para a ausência de toxidade no tratamento com Mls. Além disso, também foram realizados estudos na tentativa de buscar um alvo de ação destes compostos, investigando-se a tripanotiona redutase, enzima específica no parasito, responsável por desencadear uma cascata dedetoxificação nos parasitos. Estudos de cinética enzimática (enzimas recombinantes de L. infantum e T. cruzi) e modelagem molecular indicaram que Ml-4-NO2 é o único derivado mesoionico, dentre os estudados, capaz de inibir de forma não- competitiva esta enzima. Todos esses resultados demonstraram que Mls podem ser uma nova perspectiva no desenvolvimento de drogas com menor toxidade e capazes de modificar a resposta imunológica no combate a infecção por Leishmania, além de atuar sobre um alvo específico no parasito
Leishmaniasis is a parasitic disease with the main research priorities according to World Health Organization Aurgência drug more selective and less toxic tenm conducting research for new chemical therapies. The mesoionic compound (mls) of the class 1,3,2 - thiadiazol-2-aminida, have a broad spectrum of biological activities, including antitumor effects and antileishmanial. We investigated the in vitro activity of HH-Ml, Ml-4-NO2,-3OCH3 Ml and Ml-4-OCH3 on promastigotes and axenic amastigotes of L. infantum and intracellular amastigotes of L. infantum and L. amazonensis. A high leishmanicidal activity was demonstrated against L. infantum and it was observed a dose-response for intracellular amastigote L. infantum and L. amazonensis by ML-4-NO 2. In next step we investigate in vivo the effect of MLS in the following models mouse / parasite: CBA / J and L. amazonensis, BALB / c and L. amazonensis and BALB / c and L. infantum. In the first model, the subcutaneous administration of ML-HH and ML-4-OCH 3 led to a reduction of parasite load in lymph node adjacent to the lesion and the spleen. In both models the following, highly susceptible to infection have been studied HH-ML, ML-4-NO 2, besides evaluating parameters daresposta therapeutic and toxic potential immunomodulatory effects. Susceptible mice of BALB / c mice were infected subcutaneously in the foot with a promastigote L. by L. amazonensis and viaintraperitonal infantum. The treatments were used by inland topical, intralesional cutâna for leishmaniasis (CL) and intraperitoneal for visceral leishmaniasis (VL). Glucantime, anti-Leishmania classical drug was used as reference. While the complete healing was not observed in animals with LC, the groups treated with ML-4 - NO2 and ML-4-OCH 3 showed small lesions in the infected foot up to 12 weeks after infection without presenting ulcerations. GROUP Ml treated with LV-4-NO2 showed negative bacco parasite load and liver. Treatment of VL with Glucantime and Ml-4-OCH3 significantly reduced parasite burden. However, treatment with ML-HH in all pathways used, had no therapeutic activity for LV or LC. The evaluation of liver enzymes (ALT and AST) and creatinine indicate the absence of toxicity in the treatment mls. In addition, studies were performed in an attempt to seek a target of action of these compounds by investigating whether the trypanothione reductase, an enzyme specific to the parasite responsible for triggering a cascade dedetoxificação in parasites. Kinetic studies enzyme (enzymes of L. infantum and recombinant T. cruzi) and molecular modeling indicated that ML-4-one derivative is NO2 mesoionico, of those studied, capable of inhibiting a non-competitive this enzyme. All these results showed that MLs may be a new perspective in the development of drugs with lower toxicity and can modify the immune response to fight infection by Leishmania, and act on a specific target in the parasite

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Charret, Karen dos Santos. "Efeitos dos componentes acilhidrazonas pirazólicas sobre as formas evolutivas da Leishmania amazonensis e na infecção experimental em camundongos isogênicos CBA." reponame:Repositório Institucional da FIOCRUZ, 2011. https://www.arca.fiocruz.br/handle/icict/5831.

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Fundação Oswaldo Cruz.Instituto Oswaldo Cruz. Rio de janeiro, RJ, Brasil
Atualmente, não há vacina eficaz e o controle das leishmanioses depende principalmente da quimioterapia. Recentemente, novos compostos sintéticos os derivados carbohidrazidas pirazolocas apresentaram atividade em Leishmania amazonensis in vitro e quando testadas em modelo experimental murino de infecção de L. amazonensis mostraram eum efeito um efeito terapêutico significativo. Um estudo com compostos intermediários da síntesedas carbohidrazidas poderia ser interessante, pois estes possuem uma potencial atividade leishmanicida e ajudaria a cmpreender os mecanismos de ação dos compostos finais. Por outro lado, é necessário conhcer o comportamento do sistema imune frente a estes compostos na infecção por leishmaniose.Os compostos precursores naão foram ativos em formas promastigotas de L. amazonensis. No entanto, todos os compostos apresentaram atividade sobre formas de amastigotas e sem citotoxicidade em célula de mamíferos. Aqui, foi sugerida a contribuição farmacofórica do anel N-heteroaromático para a atividade leishmanicida e do grupamento hidrazina para o composto intermediário. Além disso, foi mostrado que todos os componentes podem induzir um aumento da produção de óxido nitrico em macrófagos estimulados ou não. Em camundongos CBA infectados com L amazonensis e tratados por via oral com os derivados carbohidrazidas, o estudo histopatológico rervelou que mudanças na derme foram correlacionadas com o tamanho macroscópico da lesão. Camundongos CBA infectados e tratados tinham lesões cutâneas menores, e as estruturas da epiderme e derme tinham níveis mais baixos de infiltrtado inflamatório, comparadas com as de camundongos controles infectados e não tratados. Também foi observado um infiltrado inflamatório misto contendo linfócitos e neutrófilos. Além disso, expressão de IL-4 RNAm foi menor no grupo tratado.. Um aumento dos níveis de anticorpos das subclasses específicas anti-Leishmania IgG2a e IgG3 foi observado nos grupos tratados com as pirozol carbohidrazidas exercem efeitos terapêuticos significativos, podendo agir diretamente sobre o parasito e/ou sobre as células dos sistemas imune do hospedeiro..
Currently, there is no effective vaccine and control of leishmanioses depends mainly on the chemotherapy. Recently, new synthetic carbohidrazidas derivatives pirazolocas compounds showed activity on Leishmania amazonensis when tested in vitro and in experimental murine model of infection of l. amazonensis showed a significant therapeutic effect effect. A study of intermediate compounds síntesedas carbohidrazidas could be interesting, as these have a potential activity leishmanicida and help cmpreender the mechanisms of action of compounds. On the other hand, it is necessary to know the behavior of the immune system against these compounds in leishmaniasis infection.The precursor compounds are active in ways does promastigotas of l. amazonensis. However, all compounds showed activity on amastigote forms and without cytotoxicity in mammalian cell. Here, it was suggested the contribution farmacofórica of the ring N-heteroaromatic compound for leishmanicida and activity of hydrazine to the intermediate grouping. In addition, it was shown that all components can induce an increase in nitric oxide production in macrophages stimulated or not. In CBA mice infected with l. amazonensis and treated orally with carbohidrazidas derivatives, the histopathologic study rervelou that changes in the DermIS were correlated with the macroscopic size of the lesion. CBA mice infected and treated tin

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Ducroz, Jean-François. "Contribution des approches cytogénétique et moléculaire a l'étude systématique et évolutive des genres de rongeurs de la division arvicanthis (rodentia, muridae)." Paris, Muséum national d'histoire naturelle, 1998. http://www.theses.fr/1998MNHN0030.

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La sous-famille des murinae, la plus nombreuse des mammifères avec 122 genres et 529 espèces décrites, pose de nombreux problèmes sur le plan systématique, notamment l'absence de tout cadre taxonomique intermédiaire entre la sous-famille et le genre. Nous nous sommes donc intéresses a un groupe de sept genres (arvicanthis, desmomys, golunda, lemniscomys, mylomys, pelomys et rhabdomys) désigne sous le terme de division arvicanthis et présente comme un regroupement supragenerique possible. L’étude systématique et évolutive de ce groupe a été envisagée par deux approches complémentaires : l'analyse cytogénétique par marquage chromosomique (chromosome banding) et l'analyse moléculaire par séquençage de tout ou partie de trois gènes mitochondriaux : le cytochrome b, l'arnr 12s et l'arnr 16s. L’analyse comparée du marquage chromosomique appliquée pour la première fois à quatre nouvelles espèces de la division (arvicanthis somalicus, lemniscomys macculus, lemniscomys rosalia et rhabdomys pumilio) a mis en évidence des remaniements chromosomiques qui ont notamment été utilises pour l'établissement de la phylogénie chromosomique du genre arvicanthis. L’arbre obtenu à partir des caractères chromosomiques est largement congruent avec les données de l'analyse moléculaire, et permet de mettre en évidence les modalités de l'évolution chromosomique dans ce genre, et le rôle de marqueurs des remaniements chromosomiques entre les différentes lignées. L’analyse moléculaire a permis de mettre en évidence la monophylie de l'ensemble forme par les six genres africains de la division et leur séparation en trois lignées distinctes : arvicanthis/mylomys/pelomys, desmomys/rhabdomys et lemniscomys. La position exacte du genre asiatique golunda n'a pu être précisée, même s'il apparait clairement appartenir à un ensemble plus large comprenant les genres africains de la division et d'autres murinae africains (aethomys, dasymys, grammomys, hybomys), ensemble pour lequel nous proposons de créer la tribu des arvicanthini. Les résultats moléculaires ont été corrélés avec une échelle temporelle en utilisant l’Age de la dichotomie mus/rattus estimée a 12 ma. Cette calibration indique que la radiation des genres de la tribu des arvicanthini se serait produite à la fin du miocène, entre 8,5 et 7 ma.

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Pereira, Natalia Rubio Claret. "Eficácia terapêutica de nanocápsulas de metotrexato em glioblastoma murino: estudos in vivo e in vitro." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-02062015-134406/.

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O glioblastoma multiforme (GBM) é uma doença grave e sem tratamento eficaz, especialmente pelos agentes terapêuticos disponíveis causarem reações adversas importantes nas doses terapêuticas. O metotrexato (MTX) é um fármaco citotóxico utilizado para tratar diversas neoplasias, no entanto, sua utilização é limitada pela baixa biodisponibilidade e reações adversas. A nanotecnologia tem sido utilizada para aumentar a eficácia dos medicamentos antitumorais, com o intuito de direcioná-los para o sítio de ação e reduzir os efeitos adversos. Nesse sentido, realizamos ensaios com nanocápsulas lipídicas de MTX (LNC MTX) para avaliar os mecanismos de captação em linhagens celulares de glioblastoma e micróglia, além investigar a eficácia terapêutica da LNC MTX em ensaios in vitro e in vivo. Inicialmente, ensaios de microscopia de fluorescência, empregando bloqueadores farmacológicos específicos para transportes de membrana, mostraram que as LNC MTX marcadas com Rodamina B penetram em células tumorais GL261 por endocitose, dependente de caveolinas, e em células de micróglia da linhagem BV2 por fagocitose e macropinocitose. Os tratamentos com LNC MTX ou solução de MTX (em concentrações correspondentes) em células GL261 inibiram a proliferação; aumentaram a fragmentação de DNA, mas, somente as LNC induziram a morte celular por necrose e diminuíram o número de células na fase G1/G0 do ciclo celular. Na linhagem celular BV2, os tratamentos com LNC MTX ou solução de MTX inibiram a proliferação, reduziram a quantidade de células na fase G1/G0 do ciclo celular, aumentaram a fragmentação de DNA e induziram morte celular por apoptose e apoptose tardia. Os ensaios in vivo de microscopia intravital mostraram que a LNC MTX atravessa a barreira Hematoencefálica (BHE) de camundongos fêmea C57Bl/6 após administração intravenosa ou oral, sem danificar a sua estrutura. O tamanho do glioblastoma in vivo foi reduzido em animais tratados com LNC MTX por via oral em relação aos animais tratados com salina. Esta redução não foi detectada em animais tratados com solução de MTX. Em conjunto, os dados obtidos mostram que a LNC MTX penetram em células de glioma e da glia e causam toxicidade, atravessam a BHE in vivo e sugerem que a nanoencapsulação do MTX pode ser uma estratégia importante para o tratamento do glioblastoma.
Glioblastoma multiforme (GBM) is a serious disease and no effective treatment is availabe, especially because the drugs cause significant adverse reactions in therapeutic doses. Methotrexate (MTX) is a cytotoxic drug used to treat many neoplasms, however, their use is limited by the low bioavailability and adverse reactions. Nanotechnology has been used to increase the effectiveness of antitumor drugs in order to direct them to the site of action and to reduce adverse effects. Accordingly, we carried out an experimental approach with MTX lipid nanocapsules (MTX LNC) to evaluate the uptake mechanisms in glioblastoma and microglia cell lines, and the therapeutic efficacy of MTX LNC in vitro and in vivo systems. Initially, fluorescence microscopy assays employing specific pharmacological blockers for membrane transport showed that the MTX LNC stained with Rhodamine B penetrated into GL261 tumor cells by caveolae-mediated endocytosis, and in BV2 microglia cells by phagocytosis and macropinocytosis. Treatment with MTX solution or MTX LNC (at corresponding concentrations) on GL261 cells inhibited the proliferation; increased DNA fragmentation, but only the LNC induced cell death by necrosis and decreased the number of cells in the G1/G0 phase of the cell cycle. In BV2 cells, treatment with MTX solution or MTX LNC inhibited proliferation, reduced number of cells in the G1/G0 phase of the cell cycle, increased DNA fragmentation and cell death, induced by apoptosis and late apoptosis. Intravital microscopy study showed that the MTX LNC across the Blood-Brain Barrier (BBB) of C57BL/6 female mice after intravenous or oral administrations, without damaging its structure. The area of glioblastoma in vivo was reduced in animals oral treated with MTX LNC comparing to saline treated mice. This reduction was not observed in animals treated with MTX solution. Together, the data herein obtained show that MTX LNC penetrate the cell membrane and cause cell toxicity on glioma and neurons lineage, cross the BBB and suggest that the nanoencapsulation of MTX can be an important strategy for the treatment of glioblastoma.

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Elhai, Muriel. "Thérapie ciblée anti-OX40 Ligand dans des modèles murins de Sclérodermie systémique." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015PA05T042/document.

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La sclérodermie systémique (ScS) est une maladie auto-immune orpheline. Elle est caractérisée par une atteinte microvasculaire et une fibrose touchant la peau et les organes internes. La ScS est une maladie sévère avec une surmortalité significative. Jusqu’à présent, aucun essai thérapeutique n’a permis de démontrer qu’un produit ait une action anti-fibrosante et améliore significativement le pronostic de cette maladie. La physiopathologie de la ScS fait intervenir une combinaison de facteurs environnementaux et de facteurs de susceptibilité génétique. Récemment TNFSF4 a été identifié comme facteur de susceptibilité génétique à la ScS. TNFSF4 code pour OX40 ligand (OX40 L). Le couple OX40-OX40L est impliqué dans la co-stimulation tardive des lymphocytes T, mais aussi dans la genèse et la réactivation de lymphocytes T mémoires et dans la prolifération et différenciation des lymphocytes B. Bloquer OX40L s’est avéré prometteur dans des modèles précliniques d’encéphalomyélite auto-immune, de polyarthrite rhumatoïde, de colite inflammatoire, de réaction du greffon contre l’hôte et d’asthme. Par ailleurs, ce blocage permettrait d’inhiber uniquement les lymphocytes T pathogènes récemment activés et d’éviter ainsi une immunosuppression globale, contrairement aux biothérapies actuellement disponibles en rhumatologie. L’observation d’une surexpression de la protéine OX40L dans le derme des patients ScS nous a incités à étudier le rôle d’OX40L dans la ScS. L’objectif de mon travail de thèse a été d’étudier l’efficacité d’une thérapie ciblée anti-OX40L dans la ScS, par l’utilisation de modèles murins complémentaires de la maladie. Nous avons tout d’abord cherché à optimiser le modèle de fibrose induite par la bléomycine, qui est un modèle bien validé, utilisé en général en première intention pour évaluer des anti-fibrosants potentiels, en particulier lorsqu’il s’agit de cibles inflammatoires. Nous avons également étudié si l’échographie à haute fréquence pouvait apporter une aide à l’évaluation cutanée chez ces animaux, mais nos résultats n’ont pas permis de démontrer une place spécifique à cet outil dans ce contexte. Les approches anti-OX40L ont débuté par l’utilisation de souris KO qui ont montré des résultats prometteurs dans le modèle induit par la bléomycine. Ensuite, des approches pharmacologiques ont été développées en utilisant un anticorps monoclonal neutralisant anti-OX40L dans le modèle de fibrose dermique induite par la bléomycine. L’intérêt du blocage d’OX40L a été conforté par la démonstration de propriétés non seulement de prévention mais aussi curatives contre la fibrose établie. L’étude des voies modulées par OX40L a mis en avant l’infiltrat inflammatoire et le relargage de cytokines pro-fibrotiques (IL-6 et TNF-α). De plus, le blocage d’OX40L semblait prévenir la fibrose dermique en inhibant l’activation des fibroblastes dépendant de la voie de signalisation AP-1. Le rôle d’OX40L dans la phase inflammatoire du remodelage matriciel a été abordé par l’utilisation du modèle de cicatrisation cutanée. En revanche, le blocage d’OX40L n’a pas eu d’effet dans le modèle de fibrose non-inflammatoire qui caractérise les souris Tsk-1. Etant donné le rôle clé en clinique de l’atteinte d’organe, notre approche a été enrichie par l’utilisation de souris transgéniques Fra2, qui sont un nouveau modèle de ScS caractérisé par une fibrose pulmonaire inflammatoire et une HTAP. L’effet de l’anticorps anti-OX40L a été remarquable dans ce contexte avec au scanner et à l’histologie une réduction significative de la fibrose pulmonaire, du remodelage vasculaire et des signes d’HTAP. Enfin, l’étude longitudinale des sérums collectés dans notre cohorte de patients a montré que la forme soluble d’OX40L pourrait être un potentiel biomarqueur dans la ScS pour identifier les patients à risque de progression sévère. (...)
Systemic sclerosis (SSc) is an autoimmune orphan disease which is characterized by alterations of the microvasculature and fibrosis affecting the skin and internal organs. SSc is the most severe connective tissue disease associated with a high risk of mortality. Until now, there is no effective treatment to counteract the fibrotic process and to improve the prognosis of this disease. SSc results from the combination of genetic and environmental factors. TNFSF4 was recently identified as a genetic risk factor for SSc. TNFSF4 encodes OX40L, which is involved in late T-cell co-stimulatory signals, but also in generation and reactivation of memory T cells and promotion of plasma cell phenotype. OX40L blockade was effective in reducing clinical symptoms in several animal models of autoimmune and inflammatory diseases, such as rheumatoid arthritis, colitis, asthma or graft-versus-host-disease. The anti-OX40L antibody presents the advantage of a targeted therapy against pathogenic recently activated T cells, which might not expose patients to increased risk of infections, unlike other conventional immunosuppressants. Following the observation of an increased expression of OX40L in fibrotic skin in SSc-patients, we aimed to investigate the contribution of OX40L in SSc and to assess the efficacy of a targeted therapy against OX40L in SSc, using complementary experimental mouse models. First, we characterized the optimum in vivo parameters required for the successful induction of dermal fibrosis in the widely used bleomycin-induced dermal fibrosis mouse model, which is usually the first step in most of pharmacological studies assessing anti-fibrotic therapies. We also aimed to determine whether ultrasonography could be used to assess skin fibrosis in this model, but our results showed that it was not efficient enough to assess dermal thickening in this model. Invalidation of OX40L prevented dermal fibrosis in the bleomycin mouse model. Then pharmacologic approaches, using a monoclonal anti-OX40L antibody, demonstrate that blockade of OX40L not only prevented dermal fibrosis, but also induced regression of established fibrosis in this model. We also showed that OX40L acts directly on both dermal fibroblasts and inflammatory cells and on cytokine release (IL-6, TNF-α), by regulating NF kappa B and AP 1 pathways. We observed that OX40L inhibition interfered with early inflammatory stages of matrix remodeling using the excisional wound healing mouse model. Conversely, blocking OX40L did not display antifibrotic properties in the non-inflammatory Tsk-1 mouse model. Given that interstitial lung involvement and pulmonary arterial hypertension (PAH) are key prognostic factors in SSc, we aimed to assess the effects of OX40L pharmacological inhibition in a new murine model: the fra-2 transgenic mice, which are characterized by both fibrosing alveolitis and PAH. In this model, using both CT-scan and histology, we demonstrated that mice treated by anti-OX40L antibody were markedly protected from fibrosing alveolitis and vessel remodeling leading to PAH. Furthermore, longitudinal analyses of our cohort of SSc-patients showed that soluble OX40L is a promising serum biomarker to predict the worsening of lung and skin fibrosis. Altogether, our results show that OX40L is as an attractive target in inflammation-driven fibrosis. This work also strengthens the relation between inflammation and fibrosis in SSc-pathogenesis. This work underlines advantages of combination of several animal models in translational approach to SSc

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Grippo, Mariangela Carnivalli. "Uso da interferencia por RNA no virus da hepatite murina tipo 3 (MHV-3)." [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316862.

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Orientadores: Iscia Teresinha Lopes-Cendes, Rovilson Gilioli
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
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Resumo: A interferência do RNA (RNAi) pode ser usada como uma ferramenta eficaz no silenciamento gênico específico mediado por moléculas de dupla fita de RNA (dsRNAs). Nesse contexto possui uma variedade de aplicações biológicas, incluindo o combate a patógenos infecciosos de importância biomédica. O objetivo do estudo foi determinar a eficiência e a especificidade da técnica de RNAi em eliminar o vírus da hepatite murina tipo 3 (MIN-3) in vitro. MHVs são vírus envelopados, cujo genoma é formado por uma cadeia de RNA fita simples (+) pertecentes a família Coronaviridae. Seu genoma codifica quatro proteínas estruturais: S (proteína da espícula); M (glicoproteína da transmembrana), N (proteína do nucleocapsídeo) e E (proteína associada à membrana) . Neste trabalho foi escolhido como alvo para o silenciamento gênico a proteína N, tendo sido produzidas moléculas de dsRNA complementares a sua seqüência genômica (GenBank AF 201929). Foram obtidas duas moléculas siRNAs transcritas por T7 RNA polimerase e uma terceira molécula interferente sintetizada comercialmente. Foi observado que os siRNAs produzidos pela transcrição in vitro, induziram uma resposta antiviral não específica. Além disso demonstrou-se que este efeito foi mediado através de substâncias secretadas no meio de cultura celular, provavelmente interferons (IFNs). Este efeito foi eficientemente eliminado após tratamento dos siRNAs com fosfatase alcalina. Observou-se também que a técnica de RNAi in vitro, tendo como alvo a proteína N de MHV-3, foi um tratamento eficaz e específico na infecção viral, confirmados através de estudos fenotípicos e moleculares. Desse modo, concluímos que experiências que utilizam RNAi contra alvos virais devem ser cuidadosamente monitoradas devido aos efeitos não específicos que podem ser induzidos por moléculas de dsRNA
Abstract: RNA Interference (RNAi) can be used as a powerful tool for post transcriptional gene-silencing mediated by double stranded RNA (dsRNAs) molecules. RNAi has a variety of biological applications including the combat against pathogens of biomedical importance. The objective of our study was to determine the efficiency and specificity of this new technique in eliminating mouse hepatitis virus type 3 (MIN-3) in vitro. MIN-3 is a subtype of enveloped viroses with a large plus-stranded RNA genome belonging to the Coronavirus family. Its genome codifies four structural proteins: S (spike protein); M (membrane protein); E (transmembrane glycoprotein); N (nucleocapsid protein). In the present study we target protein N by designing and producing dsRNA molecules complementary to its genomic sequence (GenBank AF 201929). We obtained three small interfering RNAs (siRNA) by in house T7 polymerase in vitro transcription and a fourth siRNA molecule that was commercially synthetized. We identified that siRNAs produced by in vitro transcription triggered a potent and sequence-unspecificied antiviral response. In addition, we demonstrated that this antiviral effect was mediated through molecules that were secreted in medium culture, probably interferons (IFNs). This unspecific effect was efficient1y suppressed when siRNAs were treated with aIkaline phosphatase prior to in vitro experiments. We also observed that RNAi targeting the N protein ofMIN-3 was a potent and specific treatment against in vitro infection, showing significant phenotypic protection and molecular evidence of specific gene-silencing. We concluded that experiments using RNAi against viral targets, although efficient, must be carefully controlled and monitored against possible sequence-unspecific effects triggered by dsRNA molecules
Doutorado
Genetica Animal e Evolução
Doutor em Genetica e Biologia Molecular

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Goldchmit, Sara Miriam. "Odiléa Setti Toscano: do desenho ao design." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/16/16134/tde-18012010-141648/.

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Esta pesquisa documenta e analisa uma série de trabalhos realizados pela arquiteta Odiléa Setti Toscano, entre o fim da década de cinqüenta e o início dos anos noventa, no âmbito do design visual: o design gráfico editorial vinculado ao trabalho de ilustração e o design ambiental de painéis e murais para espaços privados e públicos.
This paper documents a series of projects by architect Odiléa Setti Toscano from the late 1950s to the early 1990s, in the scope of visual design: editorial graphic design related to the work of illustration and environmental design of panels and murals for public and private spaces.

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Kmetiuk, Louise Nicolle Bach. "Desenvolvimento e avaliação comparativa do melanoma oral em camundongos, frente sua ocorrência espontânea em cães." Universidade Estadual de Ponta Grossa, 2016. http://tede2.uepg.br/jspui/handle/prefix/2761.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
ntrodução: O Melanoma é a principal neoplasia em cavidade oral de cães domésticos. Ocorre principalmente em gengiva, e caracteriza-se pela progressão acelerada, altos índices de recidiva, metástase e resistência a terapias propostas. Tais aspectos impulsionaram o presente estudo, considerando a ausência de um modelo experimental para essa neoplasia, que possibilite a realização de ensaios pré-clínicos. Objetivos: Induzir a formação de melanoma oral murino em camundongos C57Bl/6J, e estudar suas características macroscópicas e histopatológicas. Método: trata-se de um estudo experimental. Trinta camundongos C57Bl/6J (Mus musculus) foram submetidos a indução tumoral através da injeção de células da linhagem de melanoma murino B16F10 em gengiva inferior direita porção vestibular, em duas concentrações celulares, originando dois grupos distintos: Grupo 1 (n=15) que receberam 0,1 ml contendo 1x104 células de melanoma murino B16F10; Grupo 2 (n=15) que receberam 0,1 ml contendo 5x104 células de melanoma murino B16F10. Para ambos os grupos foram realizadas eutanásias programadas aos sétimo, décimo quarto e vigésimoprimeiro dias de pós-operatório, com ressecção ex-vivo da hemicabeça direita. Após a exclusão dos indivíduos que foram a óbito antes do período determinado para eutanásia, obteve-se um número de indivíduos na amostra (n) de 21. Foi realizada análise macroscópica das formações tumorais. Para o estudo histológico comparativo, analisaram-se amostras de melanoma oral canino melânico no que tange aos aspectos morfométricos e morfológicos. Resultados: Houve diferença no desenvolvimento tumoral para cada concentração celular utilizada na indução. Notouse correlação positiva entre volume tumoral e número de células. Conclusão: A indução de melanoma oral em camundongos para fins de modelo de estudo pré-clínico para cães se mostrou uma alternativa útil, viável e reproduzível.
Introduction: Melanoma is the most common neoplasm in oral cavity of dogs. Melanoma has a predilection for the gum, and it is characterized by accelerated progression and high rates of relapse, metastasis and resistance to proposed therapies. Those factors inspires the present study, considering the lack of an experimental model for melanoma. Method: This is an experimental study. Thirty C57Bl / 6J mice (Mus musculus) were submitted to tumor induction by injecting murine melanoma B16F10 cells into the right lower gum using two different cell concentrations. Mice were divided in two groups: Group 1 (n = 15) received 1x104 murine melanoma B16F10 cells injection; Group 2 (n = 15) received 5x104 murine melanoma B16F10 cells injections. For both groups, euthanasia was scheduled at the 7th., 14th. and 21th. postoperative day, with post-mortem hemi-resection of the jaw. Individuals who died before the euthanasia period were excluded, leaving 21 mice. Macroscopic analysis of tumor formations was performed. For comparative histological study, oral canine melanoma samples were analyzed for morphological aspects. Data sete analyzed with BioStat 5.3 and submitted to non-parametric statistical tests. Results: Different tumor characteristics (tumor volume, presence of irregular margins, ulceration and dark coloration) were observed for each cell concentration used in the induction, as well perfect correlation between tumor volume and tumor growth. Conclusion: The induction of oral melanoma in mice for purposes of preclinical study model for dogs is an useful, viable and reproducible alternative.

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Silva, James Fernando Malta da. "Transporte de água em células de melanona murino S91 submetidas a condições anisosmóticas." Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-29082007-092546/.

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Uma das principais necessidades da célula é a regulação do seu ambiente interno. Aparte da considerável importância teórica, o transporte de água é de importância prática numa ampla gama de processos, desde a proteção de células na preservação criogênica até os efeitos de certos hormônios em alguns tecidos. Virtualmente todas as células são submetidas a transições osmóticas durante o seu período de vida, uma vez que tanto o metabolismo intracelular quanto o transporte por membranas produzem flutuações nas concentrações dos solutos osmoticamente ativos. A regulação de volume celular é um fenômeno ubíquo e permite, às células, manter o seu volume normal. Células submetidas a choques anisosmóticos agudos sofrem rápidas alterações de volume (dependentes do gradiente osmótico e da permeabilidade da membrana à água e osmólitos) podendo ou não ser seguidas de lentas alterações regulatórias de volume. Assim, o objetivo do presente trabalho visou esclarecer alguns aspectos do transporte de água em células de melanoma murino S91 submetidas a condições anisosmóticas. Células de melanoma murino S91, foram mantidas em meio de cultura F12 HAM (290 mOsm.kgH2O-1). As medidas morfométricas das mudanças relativas de volume foram realizadas usando-se um sistema de aquisição e análise de imagens (Image Pro-Lite, Media Cybernetics). As células foram expostas tanto a choques hiposmóticos agudos (190 mOsm.kgH2O-1) como a choques hiperosmóticos agudos (350 mOsm.kgH2O-1) em diferentes temperaturas (de 17 a 37 oC) e em diferentes doses (de 0,001 a 1000 µM) de HgCl2, um bloqueador de aquaporinas (AQP). Os resultados sugerem que: (i) o tempo de regulação de volume em células de melanoma murino S91 é dependente da temperatura; (ii) o fluxo osmótico de água apresenta valores de Energia de Ativação compatíveis com aqueles propostos para o trânsito de água através de aquaporinas (Ea < 6 kcal.mol-1); (iii) o HgCl2 afeta de forma dose dependente as respostas osmóticas em células de melanoma murino S91 e sugerem a presença de mais de um tipo de AQP. Nestas condições as concentrações necessárias para reduzir ao máximo a permeabilidade osmótica à água estão localizadas na faixa de 0,1-1,0 µM HgCl2.
One of the major needs of living cells is the regulation of their internal environment. Apart from being of considerable theoretical importance, the transport of water is of practical importance in a broad range of process, from the protection of cells undergoing cryogenic preservation to the effects of certain hormones in some tissues. Virtually all the cells are submitted the osmotic transitions during their period of life, because both intracellular metabolism and transmembrane transport produce fluctuations in concentrations of osmolytes. The regulation of cellular volume is a phenomenon ubiquitous and allows, to the cells, to keep their normal volume. Cells subjected to acute anisosmotic shocks suffer from fast alterations in volume (depending on the osmotic gradient and on the permeability of the membrane to the water and osmotically active substances), and followed or not by a slow volume regulation response. Thus, the present work aims to clarify some aspects of the water transport in murine melanoma S91 cells subjected to anisosmotic conditions. S91 murine melanoma cells were grown in F12 HAM medium (290 mOsm.kgH2O-1). Morphometric measurements of relative changes in cell volume were performed using a video microscopy system and a PC software (Image Pro-Lite, Media Cybernetics). The experimental cells were exposed either to acute hyposmotic shocks (190 mOsm.kgH2O-1) or to acute hyperosmotic shocks (350 mOsm.kgH2O-1), in different temperatures (ranging from 17 to 37 oC) and in the presence of HgCl2 (from 0,001 to 1000 µM), an aquaporin blocker. The results of the present study indicate that: (i) the time of volume regulation in S91 murine melanoma cells is dependent on temperature; (ii) the values of osmotic water flow are compatible with activation energy through aquaporins (E < 6 kcal.mol-1) and (iii) HgCl2 treatments affect osmotic behavior of S91 murine melanoma cells in a dose-response manner and also suggest the presence of more than one type of aquaporin. Minimum osmotic water permeabilities were observed in a range of µM HgCl2 treatments.

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Zgheib, Sara. "Altérations physiologiques et récupération à long terme dans un modéle murin de séparation associée à une restriction du temps d'accés à l'alimentation : un outil pour l'étude des conséquences de l'anorexie mentale." Thesis, Littoral, 2014. http://www.theses.fr/2014DUNK0428/document.

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L'anorexie mentale (AM) est un trouble du comportement alimentaire qui se caractérise par une recherche obsessionnelle de minceur, une forte réduction de la prise alimentaire et une distorsion de l'image de soi. Elle est associée à de multiples perturbations endocriniennes et métaboliques, et à une altération de la masse et de la microarchitecture osseuses. Les facteurs et les mécanismes qui interviennent dans cette maladie sont très mal connus ce qui limite les options thérapeutiques. Il est donc nécessaire de développer un modèle animal qui reproduise les perturbations physiologiques observées en AM et permette d'étudier les facteurs associés à l'altération osseuse. Dans ce but nous avons développé un modèle murin avec une restriction du temps d'accès à l'alimentation associée à un stress induit par la séparation (separation-based anorexia, SBA). Cette phase SBA de 10 semaines est suivie d'une phase de récupération en conditions standard (REC) de 10 semaines. Chez les souris femelles C57B1/6 en fin de croissance rapide, la phase SBA induit une perte rapide et importante du poids corporel. L'analyse de la composition corporelle par DEXA révèle une diminution rapide de près de 40% de la masse grasse ainsi qu'une baisse progressive de la masse maigre et un arrêt de l'acquisition de la masse osseuse. Au niveau des tibias, la densité minérale cortical et la microarchitecture trabéculaire sont altérées. L'observation des frottis vaginaux et la mesure des ovaires révèlent une perturbation importante des fonctions reproductrices. Les tests de tolérance au glucose ont montré que les souris SBA ont une capacité très élevée à corriger la glycémie. Ces animaux sont fortement hypoleptinémiques, et l'axe GH-IGF-1 est très perturbé. L'étude de l'expression génique de différents tissus adipeux a montré une augmentation du niveau des marqueurs de lipogénèse et de lipolyse, ainsi qu'une forte induction du phénotype "adipocyte brun" dans le tissu adipeux sous-cutané. Après deux semaines de REC, les souris SBA retrouvent très rapidement leur poids corporel, leurs masses maigre et grasse. La masse minérale toujours basse à ce stade est corrigée après 10 semaines de REC, ainsi que la microarchitecture osseuse (étude préliminaire). Tous les autres paramètres étudiés sont normalisés, sauf l'hypoleptinémie qui étonnamment persiste même après 10 semaines de protocol REC et malgré la normalisation de la masse adipeuse. D'après ces résultats, on peut conclure que le modèle SBA reproduit de nombreuses perturbations physiologiques observées en AM. La phase de REC révèle que ces souris ont une importante capacité de récupération. L'hypoleptinémie persistante pourrait favoriser la récupération. L'identification des mécanismes impliqués pourrait fournir des pistes thérapeutiques afin de favoriser la reconstitution du capital osseux des patientes anorexiques
Anorexia nervosa (AN) is an eating disorder mainly developed in adolescent girls and young women. It is characterized by an obsessive search for thinness, a profound undernutrition and a distorted self-image.It is associated with multiple endocrine and metabolic disturbances, decreased bone mass and microarchitectural alteration. Some of the developed adaptations are supposed to be involved in the blockade of the pathologic state. Unfortunately, these adaptations are poorly known and most of them cannot be studied on patients. So it is necessary to develop an animal model which mimics the main consequences observed in human pathology and allows studying the recovery process. For this purpose we adapted a murine model of time restricted feeding associated with chronic stress induced by separation-based anorexia (SBA). C57B1/6 female mice are submitted to a long term SBA protocol (10 weeks) and then a long term phase of recovery (10 weeks). At the beginning of the protocol mice are 8 weeks old, so their fast growth is finishing. SBA protocol induced a rapid and significant loss of body weight. Body composition analysis by DEXA showed a 40% decrease of the fat mass, a progressive loss of lean mass and a blockade of bone mass acquisition. Mice deveoped a high glucose tolerance. The observation of vaginal smears revealed a disruption of the estrous cycle and ovarian histology showed an atrophy of the ovaries. These two alterations suggest a major alteration of reproductive functions. These animals showed a very low leptinemia, and the GH/IGF-1 axis was disrupted. The study of bone alteration by microtomography indicated an alteration of bone microarchitecture and of cortical bone mass, mimicking osteoporosis often described in AN patients. Body weight, lean and fat masses were normalized quickly during the REC protocol. Bone mineral content still low after 2 weeks of REC protocol was fully corrected after 10 weeks. The estrous cycle ovarian size and the GH/IGF-I were normalized. Surprisingly, hypoleptinemia persisted even after 10 weeks of REC and despite the normalization of the fat mass. This result has been confirmed by the low level of leptin gene expression in various adipose tissues. Finally, the SBA protocol is valuable model of AN because numerous physiological alterations described in AN are mimicked in this model. The recovery phase revealed the high capacity of mice to normalize the long term alterations. Persitent hypoleptinemia could contribute to the normalization of body composition. However, the balance between central and peripheral effects of the uncorrected hypoleptinemia remains to be determined. This persisting hypoleptinemia could be used for the revision of the therapeutic strategies aiming to correct AN-induced osteoporosis

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Hansner, Thomas. "Molekularbiologische und proteinchemische Charakterisierung einer Thiolproteinase des einzelligen Parasiten Sarcocystis muris (Apicomplexa)." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960418563.

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Bezine, Maryem. "Implication du canal potassium Kv3.1 dans la lipotoxicité du 7-cétocholestérol, 24S-hydroxycholestérol et de l’acide tétracosanoïque sur des cellules nerveuses 158N et BV-2 : Etude des relations entre Kv3.1, homéostasie potassique et métabolisme peroxysomal dans la maladie d’Alzheimer." Thesis, Bourgogne Franche-Comté, 2017. http://www.theses.fr/2017UBFCI010/document.

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Le potassium (K+) est impliqué dans la régulation de l’excitabilité cellulaire, la régulation du cycle cellulaire, la viabilité cellulaire, la neuroprotection et le maintien des fonctions microgliales et oligodendrocytaires. Le dysfonctionnement des canaux potassiques, décrit dans plusieurs maladies neurodégénératives comme la Maladie d’Alzheimer (MA), la sclérose en plaques (SEP), la maladie de Parkinson et la maladie de Huntington, pourrait être une potentiel cible thérapeutique. Les mécanismes toxiques sous-jacents de ces pathologies neurodégénératives impliquent des oxystérols, dérivés oxydés du cholestérol, et des acides gras en relation avec le métabolisme peroxysomal. Le 7-cétocholestérol (7KC), le 24S-hydroxycholestérol (24S-OHC) et l'acide tétracosanoïque (C24: 0), souvent trouvés à des taux élevés au niveau du cerveau et dans le plasma de patients atteints de maladies neurodégénératives (MA, maladie de Nieman-Pick, SEP, maladie de Parkinson, maladie de Huntington et X-ALD conduisent une rupture de l’équilibre Redox qui aboutirait à la neurodégénérescence. Dans ce contexte, il est intéressant de déterminer l’éventuelle connexion entre environnement lipidique et homéostasie potassique. L’étude in vitro a été réalisée sur des olygodendrocytes murins 158N et les cellules microgliale BV-2. Nous avons montré que la lipotoxicité du 7KC, 24S-OHC et C24:0 implique une rétention du K+ faisant intervenir les canaux potassium voltage dépendant (Kv). Ces résultats ont montré que l'inhibition des canaux Kv conduisant à une augmentation la [K+]i contribue à la cytotoxicité du 7KC, 24S-OHC et C24:0. Nous nous sommes focalisés sur le canal Kv3.1b. La retention du K+ induite par les oxystérols (7KC et 24S-OHC) serait sous le contrôle de Kv3.1b. L’étude clinique réalisée sur du plasma de MA a révélé une corrélation négative entre le taux d’acide docosahexaénoïque (DHA) et la concentration de K+. Chez les souris transgéniques J20, modèle de la MA, l’étude de la topographie d’expression de Kv3.1b et d’Abcd3, au niveau de l’hippocampe et du cortex, a montré une baisse de l’expression de ces deux marqueurs. Dans leur ensemble, les résultats obtenus ont établi des relations entre lipotoxicité, métabolisme peroxysomal et altération de l’homéostasie potassique dans la neurodégénérescence et suggèrent une possible modulation de l’expression et de l’activité de kv3.1b dans la physiopathologie des maladies neurodégénératives
Potassium (K+) is involved in the regulation of cellular excitability, cell cycle regulation, cell viability, neuroprotection and maintenance of microglial and oligodendrocytic functions. Potassium dysfunction, described in several neurodegenerative diseases such as Alzheimer's Disease (AD), multiple sclerosis (MS), Parkinson's disease and Huntington's disease, may be a potential therapeutic target. The underlying toxic mechanisms of these neurodegenerative pathologies involve oxysterols, which are oxidized cholesterol derivatives, and fatty acids including those associated with peroxisomal metabolism. 7-ketocholesterol (7KC), 24S-hydroxycholesterol (24S-OHC) and tetracosanoic acid (C24:0), often found at increased levels in the brain and plasma of patients with neurodegenerative diseases (Nieman-Pick disease, MS, Parkinson's disease, Huntington's disease and X-ALD) lead to a breakdown of the redox equilibrium leading to neurodegeneration. In this context, it is interesting to determine the possible connection between the lipid environment and potassium homeostasis The in vitro study was carried out on 158N murine oligodendrocytes and microglial BV-2 cells. We have shown that the lipotoxicity of 7KC, 24S-OHC and C24:0 implies retention of K+ involving the voltage dependent potassium channels (Kv). These results have shown that inhibition of Kv channels lead to an increase in [K +] i contributing to the cytotoxicity of 7KC, 24S-OHC and C24:0. The retention of K+ induced by oxysterols (7KC and 24S-OHC) would be under the control of Kv3.1b. A clinical study, on plasma of patients with Alzheimer’s disease, revealed a negative correlation between docosahexaenoic acid (DHA) and K+ concentration. In the J20 mice, a transgenic model of Alzheimer’s disease, the expression of Kv3.1b and Abcd3 was decreased in the hippocampus and cortex. Overall, the results obtained established relationships between lipotoxicity, peroxisomal metabolism and potassium homeostasis in neurodegeneration and suggest a possible modulation of the expression and activity of kv3.1b in the pathophysiology of neurodegenerative diseases. So, modulation of Kv3.1 could constitute a new therapeuthic approach against some neurodegenerative diseases

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Mathieu, Marie-Emmanuelle. "Etude de la balance pluripotence-differenciation des cellules souches embryonnaires murines sous l'effet du LIF : rôle du gène MRAS." Thesis, Bordeaux 2, 2011. http://www.theses.fr/2011BOR21878/document.

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Le LIF (Leukemia Inhibitory factor), une cytokine de la famille de l’Interleukine 6, permet le maintien de la pluripotence des cellules souches embryonnaires murines (CSEm) in vitro. Dans le but de comprendre les mécanismes d’action du LIF dans ce modèle d’étude, une analyse sur puces à ADN a été réalisée et a permis d’identifier trois « signatures LIF » : les gènes « Pluri » (pour Pluripotence), dont le niveau d’expression relatif chute suite au retrait de cette cytokine, et deux catégories de gènes « Lifind » (pour LIF induit) dont le niveau d’expression relatif augmente suite à un ajout de LIF après une culture de 24 ou 48 heures sans cette cytokine. Nous avons mis au point des tests fonctionnels permettant d’étudier la fonction des gènes cibles du LIF dans notre modèle d’étude. Ainsi, nous avons mis en évidence le rôle d’un gène « Pluri », Mras/Rras3, une petite GTPase de la famille Ras, dans la régulation de l’expression d’une part de marqueurs de pluripotence, tels que Oct4 et Nanog et d’autre part de marqueurs de différenciation, tels que Lef1 et Fgf5
LIF (Leukemia Inhibitory factor), a cytokine Interleukin 6 family, allows maintaining the pluripotency of murine embryonic stem cells (mESC) in vitro. To understand the mechanisms of action of the LIF in this model, a microarray analysis was conducted and identified three « signatures LIF » : the « Pluri » (for Pluripotency) genes, whose the relative level of expression falls following the withdrawal of this cytokine, and two classes of « Lifind » (for LIF induced) genes, whose the relative expression level increases as a result of LIF addition after a culture of 24 or 48 hours without this cytokine. We have developed functional tests to study the function of the target genes of LIF in our study model. Thus, we have investigated the role of a « Pluri » gene, Mras/Rras3, a small GTPase of the Ras family, in the regulation of the expression on the one hand of markers of pluripotency, such as Oct4 and Nanog, and on the other hand of differentiation markers, such as Lef1 and Fgf5

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Pereira, Beatriz Aparecida Soares. "Patogenicidade e imunogenicidade de isolados clínicos do complexo Paracoccidioides brasiliensis." Botucatu, 2019. http://hdl.handle.net/11449/181206.

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Orientador: Rinaldo Poncio Mendes
Resumo: Introdução. A correlação entre gravidade da paracoccidioidomicose e patogenicidade e imunogenicidade dos fungos causadores tem sido pouco investigada e foi o objetivo deste estudo. Metodologia. As cincos cepas Pb192, Pb234, Pb326, Pb417 e Pb531 foram identificadas pelo seqüenciamento da região Exon 2 da gp43. A patogenicidade foi determinada pelo cálculo da dose letal 50% (DL50%) e pela contagem do número de unidades formadoras de colônias, realizada na sexta semana pós-infecção de camundongos BALB/c. A imunogenicidade foi determinada pela avaliação da resposta imune humoral específica, utilizando-se a reação de imunodifusão dupla em gel de ágar e da imunidade celular, determinada pela concentração das citocinas interleucina -2, interleucina-10, interferon-γ, fator de necrose tumoral – α e do fator de crescimento do endotélio vascular, em tecido pulmonar. Quatro amostras clínicas foram recém-isoladas de pacientes com paracoccidioidomicose, provenientes da Região de Botucatu - os isolados Pb234 e Pb417, de pacientes com a forma crônica moderada; o Pb326 de um caso com a forma aguda grave; e o Pb531, de um caso com a forma crônica grave. As demais cepas Pb192, Pb01 e 8334 foram cedidas pelo laboratório de Moléstias infecciosas. Resultados. As cepas Pb417 e Pb326 agruparam-se às cepas identificadas como P. brasiliensis S1a, a Pb531 às P. brasiliensis S1b e as cepas Pb234 e Pb192 às cepas depositadas como P. restrepiensis (PS3). Os resultados demonstraram correlação direta entre ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Introduction. The investigation of paracoccidioidomycosis and pathogenicity and immunogenicity of the provoking fungi has been little investigated and was the objective of this study. Methodology. As strains, Pb192, Pb234, Pb326, Pb417 and Pb531 were included by sequencing the Exon 2 region of gp43. The pathogenicity was determined by calculating the 50% lethal dose (LD50%) and by counting the number of colony forming units performed in the sixth week post-infection of BALB / c mice. Immunogenicity was determined by the humoral immune response, using the agar gel immunodiffusion reaction and the cellular immunity, determined the concentration of cytokines interleukin-2, interleukin-10, interferonγ, tumor necrosis factor - and factor of vascular endothelial growth in lung tissue. Surgical has been associated with patients with paracoccidioidomycosis, derived from the Botucatu - the Pb234 and Pb417; the Pb326 of a case with a severe severe form; and Pb531, of a case with severe chronic form. The other strains Pb192, Pb01 and 8334 were transferred by the laboratory of Infectious Diseases. Results. Pb417 and Pb326 strains were grouped into the associated strains P. brasiliensis S1a, Pb531 to P. brasiliensis S1b and strains Pb234 and Pb192 to strains deposited as P. restrepiensis (PS3). The results demonstrate the pathogenicity of disease error and severity. The small LD 50 values were measured in the following cases: severe disease, Pb531 and Pb326. Pb531 strain was considered to... (Complete abstract click electronic access below)
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21

Silva, Muriel Vilela Teodoro. "Avaliação do efeito da expressão do gene da interleucina 32 (IL-32) humana em modelo murino de infecção por Leishmania (Leishmania) amazonensis." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/6333.

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Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG
IL-32 is a proinflammatory cytokine which has different isoforms. IL-32γ isoform is the most powerful and was detected in lesions of patients with cutaneous leishmaniasis. Murine cells respond to IL-32, however mice lack the gene for this cytokine. To understand the role of IL- 32 in Leishmania (L.) amazonensis, we used transgenic mice for human IL-32γ (IL-32γTg). C57BL/6 mice (WT) and C57BL/6 IL-32γTg were infected with L. amazonensis promastigotes in the ear. The lesion development was followed weekly with a digital caliper (measured in mm of injury). After 3, 6 and 9 weeks, the animals were euthanized for tissue parasitism analysis by the limiting dilution technique, in infected ears, draining lymph node and spleen of mice. The draining lymph node cells were incubated (48 h) in the presence or absence of L. amazonensis antigen (Ag) for analysis of cytokines by ELISA. IL-32γTg mice present IL-32 production in spleen, liver, lymph node and ear. IL-32γTg mice have a lower injury than the WT mice during the third week of infection. From the 5th to the 9th week of infection, the two groups had similar lesion development profiles. Interestingly, in the 3rd week of infection, the parasitic load in the lesion of IL-32γTg mice was 100 times greater than that of WT mice. After three weeks, IL-32γTg mice maintained the same parasitic load up to nine weeks. In WT mice, however, the number of parasites increased exponentially during weeks evaluated. The parasite load in the spleen and lymph node was lower in IL-32γTg mice when compared with WT mice. There was no difference in histological sections of the lesions in WT and IL-32γTg mice infected with L. amazonensis. We did not observe differences between WT and IL-32γTg groups on the product -10) by lymph node cells stimulated with Ag, in the 3rd, 6th and 9th week of infection. Our data suggest that IL-32γ favors infection by L. amazonensis in the early stages, allowing the growth of the parasites. However, this cytokine seems to limit the growth and spread of parasites in the later stages of infection. In vitro analyzes show the similar percentage of infected cells and the number of parasites per infected cell in WT macrophages and IL-32γTg after 3 and 48h of infection with L. amazonensis. However, the production of NO by macrophages seems to be lower in IL- 32γTg mouse cells during infection with L. amazonensis. Understanding the mechanisms by which IL-32γ modulates Leishmania amazonensis infection in mice is essential to define the components that control cutaneous leishmaniasis caused by this specie in humans.
A IL-32 é uma citocina pró-inflamatória que apresenta diferentes isoformas. A isoforma IL- 32γ é a mais potente e foi detectada em lesões de pacientes com leishmaniose tegumentar americana. Células murinas respondem à IL-32, no entanto, camundongos não têm o gene para essa citocina. Para entender o papel da IL-32 na infecção por Leishmania (Leishmania) amazonensis, foram utilizados camundongos transgênicos para a IL-32γ humana (IL-32γTg). Camundongos C57BL/6 (WT) e C57BL/6 IL-32γTg foram infectados com formas promastigotas de L. amazonensis na orelha. O desenvolvimento da lesão foi acompanhado semanalmente com paquímetro digital (medida em mm de lesão). Após 3, 6 e 9 semanas, os animais foram eutanasiados para análise de parasitismo tecidual, pela técnica de diluição limitante, nas orelhas infectadas, no linfonodo drenante e no baço dos camundongos. As células do linfonodo drenante foram incubadas (48 h), na presença ou ausência de antígeno de L. amazonensis (Ag), para análise de citocinas pela técnica de ELISA. Camundongos IL- 32γTg apresentam produção de IL-32 no baço, fígado, linfonodo e orelha. Camundongos IL- 32γTg apresentam uma lesão menor do que a lesão dos camundongos WT, na terceira semana de infecção. Da 5ª até a 9a semana de infecção, os dois grupos apresentaram perfis semelhantes de desenvolvimento da lesão. Curiosamente, na 3ª semana de infecção, a carga parasitária na lesão do camundongo IL-32γTg era 100 vezes maior do que a dos camundongos WT. Após três semanas, os camundongos IL-32γTg mantiveram a mesma carga parasitária até nove semanas. Em camundongos WT, no entanto, o número de parasitos aumentou exponencialmente durante as semanas avaliadas. A carga parasitária do linfonodo e no baço foi menor nos camundongos IL-32γTg, quando comparado com camundongos WT. Não foi observada diferença nos perfis histológicos das lesões nos camundongos WT e IL-32γTg infectados por L. amazonensis. Não foi observada nenhuma diferença entre os grupos WT e IL-32γTg em relação à produção de citocinas (IFNγ, TNFα e IL-10), pelas células dos linfonodos estimuladas com Ag, na 3a, 6a e 9a semana de infecção. Os nossos dados sugerem que a IL-32γ favorece a infecção por L. amazonensis nas fases iniciais, permitindo o crescimento do parasito; no entanto, essa citocina parece limitar o crescimento e a disseminação dos parasitos nas fases mais tardias da infecção. As análises in vitro mostraram porcentagem de células infectadas e número de parasitas por célula infectada semelhantes nos macrófagos dos WT e IL-32γTg com 3 e 48h de infecção por L. amazonensis. Entretanto, a produção de NO por macrófagos parece ser menor nas células de camundongos IL-32γTg durante a infecção por L. amazonensis. Compreender os mecanismos pelos quais a IL-32γ modula a infecção por L. amazonensis nos camundongos é fundamental para a definição dos componentes que controlam a leishmaniose tegumentar causada por esta espécie em seres humanos.

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Zapana, Priscila Rosse Mamani. "Desenvolvimento de um modelo murino para estudo da resposta imune conferida pela proteína do Nucleocapsídeo do vírus Oropouche." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/17/17147/tde-25042018-153023/.

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O vírus Oropouche (OROV) é um arbovírus que ocorre na região amazônica causando surtos de doenças febris agudas e que, ocasionalmente, podem ser associados a meningoencefalite. Aproximadamente 500.000 casos de Oropouche teriam ocorrido no Brasil. Entretanto, não existe vacina contra o OROV. O objetivo deste trabalho foi desenvolver um modelo animal de infecção por OROV para estudar a patogênese da doença e um modelo para testar candidatas vacinais. Protótipo vacinal utilizando a proteína recombinante do nucleocapsídeo (N) de OROV (NrOROV), que é o principal antígeno viral, foi usado como potencial candidato para vacina. Neste estudo utilizou-se um modelo animal em camundongos Balb/c de 12 semanas de idade, inoculados intracerebralmente com 8x105 PFU de OROV, capaz de induzir 100% de letalidade após o terceiro dia da infecção. Altos títulos virais foram encontrados no cérebro e na medula espinhal dos animais. Surpreendentemente, 12 e 24 horas pós-infecção foi possível detectar vírus no fígado e baço (3 Log10 PFU/g) dos camundongos. Com este modelo foram testados os candidatos vacinais. Grupos de camundongos foram imunizados 3 vezes com OROV, OROV e FCA, NrOROV, NrOROV e FCA, NrOROV, Poli I:C e Montanide ISA 720. Após 3 imunizações, os animais foram desafiados com 10 LD50 de OROV e observados por 20 dias. Os animais imunizados com NrOROV e adjuvantes, não foram capazes de produzir anticorpos neutralizantes e adquirir imunidade protetora contra OROV enquanto que os imunizados com OROV apresentaram altos níveis de anticorpos neutralizantes e completa proteção in vivo. Ainda, os anticorpos produzidos pelos animais imunizados permitiram estudar o ciclo de replicação celular do OROV utilizando imunofluorescência.
Oropouche (OROV) is an arbovirus that occurs in the South American, Amazon region, producing outbreaks of acute febrile illness occasionally associated to meningoencephalitis. Approximately 500,000 cases of Oropouche have been reported in Brazil in the last 60 years. However, there is no available vaccine for OROV. We show here the development of an animal model of OROV suitable for studies on pathogenesis and vaccine testing. A vaccine prototype based on recombinant OROV nucleocapsid protein (NrOROV), an important viral antigen, was evaluated in the animal model. Initialy, we observed that all 12-week-old Balb/c mice inoculated intracerebrally with 8x105 PFU died after the third day of infection. Surprisingly, OROV genome was detectable in the liver as early as 12 hours post infection (pi) and in the spleen at 24 hours pi at 3 log10 PFU/g. Besides, high viral titers were found in brain and spinal cord. To test the NrOROV as a vaccine candidate, animals divided in 5 groups were immunized subcutaneously 3 times, two weeks apart with either OROV, OROV and Freud complete Adjuvant (FCA), NrOROV, NrOROV and FCA, NrOROV and Poly I:C and Montanide ISA 720. The experiment also included a group of naïve animals. After the third immunization, the animals were challenged with 10LD50 by intracerebral route and followed for 20 days. The animals immunized with NrOROV and adjuvants developed specific antibodies that were not able to neutralize the virus or confer protective immunity against OROV. Nevertheless, mice immunized with OROV showed high levels of neutralizing and protective antibodies. Despite the discouraging results with NrOROV as a vaccine, the mouse model is suitable to study pathogenesis, and to test other vaccines for OROV.

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Araújo, Rychardson Rocha de. "Fenologia e morfologia de plantas e biometria de frutos e sementes de muricizeiro (Byrsonima verbascifolia (L.) Rich.) do tabuleiro costeiro de Alagoas." Universidade Federal Rural do Semi-Árido, 2009. http://bdtd.ufersa.edu.br:80/tede/handle/tede/127.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Muricy (Byrsonima verbascifolia (L.) Rich.) is distinguished as a tropical fruit species of ample distribution in the Cerrados and coastal plains of Brazil. Even though its botanical importance and economic potential, very few studies have been carried out with this species that lacks knowledge in relation to its physiological and phenological behavior. The objective of this work was to study the phenology and morphology of plants, fruits and seeds of twenty native adult plants in a natural coastal plain area of the state of Alagoas. All selected plants had presented a clear synchronism in all studied phenophases. The leaves abscission of the plants occurred all throughout the studied period, but it was more intense in the driest months of the year (September to November) and was always followed by the sprouting of new leaf buds and flowers. On the other hand, the fruit production was concentrated mainly between December and February. Reproductive phenophases in the plants showed to be dependent on the environment where they grew, since the same species studied in other regions presented different reproductive periods. The correlation between the main morphometric indices of the plants canopy (total height of the plant, diameter, length and ratio of canopy) indicated that they were positively correlated with the diameter of the stem at the ground level. The total height was only positively correlated with the diameter and length of the canopy. The biometric analyses showed that the mean weight of the fresh fruits was of 1.21 g, the longitudinal diameter and the transversal line of the fruits were, respectively, 8,5 millimeters and 7,4 millimeters, and the mean proportion of the pulp was of 63%. The mean fresh mass of the fruits was proportional to the amount of pulp (r = 0.605; P < 0.05), indicating an interesting potential for future works of plant improvement in this species.
O murici (Byrsonima verbascifolia (L.) Rich.) destaca-se como uma espécie frutífera de ampla distribuição nos cerrados e tabuleiros costeiros brasileiro. Apesar de sua importância botânica e de seu potencial econômico, essa espécie tem sido pouco estudada, principalmente, em relação ao seu comportamento fisiológico e fenológico diante das variações no ambiente físico em que se desenvolve. O objetivo desse trabalho foi estudar a fenologia e caracterizar morfologicamente as plantas, frutos e sementes de vinte plantas adultas nativas de uma área natural de tabuleiro costeiro localizada na zona rural do litoral norte do estado de Alagoas. As vinte plantas selecionadas apresentaram claro sincronismo em todas as fenofases estudadas. A abscisão das folhas das plantas ocorreu ao longo de todo o período estudado, mas foi mais intensa nos meses mais secos (setembro a novembro) e foi sempre acompanhada da brotação de novas gemas e flores. Por outro lado, a frutificação concentrou-se principalmente entre os meses de dezembro a fevereiro. As fenofases reprodutivas foram dependentes do ambiente onde se desenvolveram, visto que a mesma espécie estudada em outras regiões apresentou períodos reprodutivos diferentes. A correlação dos principais índices morfométricos da copa indicaram que existem correlações positivas do diâmetro do caule ao nível do solo com os índices altura total, diâmetro, comprimento e proporção de copa. Para a altura total foram encontradas correlações somente com diâmetro de copa e comprimento de copa. As análises biométricas mostraram que o peso médio dos frutos frescos foi de 1.21 g, o diâmetro longitudinal e o transversal das frutas foram, respectivamente, 8.5 milímetros e 7.4 milímetros, e o rendimento médio da polpa foi de 63%. A massa fresca média dos frutos foi proporcional à quantidade de polpa (r = 0.605; P < 0.05), indicando um potencial interessante para futuros trabalhos de seleção de árvores de elite com vistas ao melhoramento genético da espécie.

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Wanji, Samuel. "Un nouveau modèle pour la thérapeutique de l'onchocercose : la filaire de muridés à microfilaires dermiques, "Monanema martini"." Montpellier 2, 1992. http://www.theses.fr/1992MON20294.

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Le travail est la mise au point d'un outil la filaire monanema martini, a microfilaires dermiques, parasite de murides pour aborder les problemes de pathologie de l'onchocercose et sa therapeutique dans de bonnes conditions. Les larves migrent par le systeme lymphatique; celles qui restent dans le conjonctif sous-cutane sont detruites par la reaction inflammatoire. Le pourcentage de filaires qui se developperont est donc etabli des le premier jour et est independant de la dose de larves inoculees. Ces faits ont une valeur generale (4 autres especes etudiees ici). Il en resulte aussi que toute filaire, par la voie du canal thoracique, peut passer dans la circulation sanguine cardio-pulmonaire. Les igm et igc diriges contre m. Martini sont presents chez les hotes infectes et restent longtemps a des taux eleves. Les filaires adultes engendrent peu de lesions mais les larves et les microfilaires sont responsables de lesions dans le conjonctif dermique, corneen et perilymphatique, semblables a celles de l'onchocercose. Les microfilaires sont intralymphatiques et leur sortie accidentelle declenche un processus inflammatoire dont la somme est une maladie chronique. L'evaluation de 7 produits antifilariens (albenzadole, umf 078, cgp 20376, cgi 18041, cgp 6140, ivermectine) montre que la sensibilite de m. Martini a ces drogues est assez comparable aux donnees de la litterature. Mais le modele permet en outre d'etudier par l'anatomo-pathologie les effets adverses dur l'hote: certains produits provoquent la sortie synchrone des microfilaires et exacerbent la maladie, d'autres provoquent la migration des filaires dans les vaisseaux pulmonaires et entrainent des thrombolymphangites

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Amirayan, Nathalie. "Les molécules de classe I du complexe majeur d'histocompatibilité : molécules accessoires de l'activation des lymphocytes T murins." Aix-Marseille 2, 1994. http://www.theses.fr/1994AIX22090.

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La reponse immunitaire est le fruit d'un dialogue intermoleculaire: le tcr qui assure la specificite de la reponse reconnait l'ag en association avec les molecules du cmh. Simultanement les co-recepteurs cd4 ou cd8 reconnaissent la partie monomorphe des molecules de classe ii ou de classe i du cmh, respectivement. Parallelement, les molecules dites accessoires transmettent des signaux de co-stimulation apres engagement avec leur ligand specifique. L'ensemble de ces phenomenes necessite un etroit controle pour eviter les reactions excessives. Les molecules de classe i exprimees a la surface des lymphocytes t murins, pourraient aussi intervenir au cours de ces etapes regulatrices. En effet, les ac specifiques des domaines alpha 1 et alpha 2 de ces molecules inhibent la proliferation des lymphocytes t, en reponse primaire uniquement. Ces resultats suggerent que les molecules de classe i, comme d'autres molecules accessoires ne sont plus necessaires au cours des reponses secondaires. A l'aide de souris transgeniques dont les cellules expriment les molecules de classe i qa-2, ancrees dans la membrane par un phosphatidyl inositol, on a mis en evidence que les parties intracytoplasmique et transmembranaire des molecules de classe i ne sont pas impliquees dans la transmission du signal. Il semblerait donc que les molecules de classe i soient associees par leur domaine extracytoplasmique a une ou plusieurs autres molecules qui transmettent ce signal. La fixation des ac sur ces molecules de classe i induirait la dissociation avec cette ou ces molecule(s) en cis empechant ainsi la transmission du signal. De plus, la presence des molecules de classe i lors de la signalisation induite par les molecules thy-1 semble indispensable, ce qui implique que les molecules thy-1 font partie d'un complexe multimoleculaire forme par les molecules de classe i et la ou les molecule(s) transmettant le signal. D'autre part, les ac diriges contre les molecules de classe i semblent inhiber l'etape d'activation de la pkc car les etapes en amont telles que le flux calcique ou la phosphorylation precoce des tyrosines sont normaux alors que tous les evenements qui suivent l'activation de la pkc sont inhibes en presence des ac diriges contre les molecules de classe i. L'ensemble de ces resultats nous montre que les molecules de classe i jouent effectivement un role au cours de l'activation des lymphocytes t murins, en formant un complexe multimoleculaire capable de transmettre des signaux aux cellules t

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Silva, Elizangela dos Anjos. "Avaliação morfológica e molecular pós-tratamento com os fatores hepatotróficos, da cirrose hepática induzida em ratas pela tioacetamida: análise a curto e longo prazo." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/10/10132/tde-03042012-163500/.

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A cirrose hepática é um processo irreversível caracterizado pelo desequilíbrio entre a deposição e a degradação de componentes da matriz extracelular (MEC), acarretando disfunção hepatocelular e aumento da resistência ao fluxo sanguíneo, resultando em insuficiência hepática e na hipertensão portal. A cirrose em cães, muitas vezes é identificada nos estágios finais, já que o estágio inicial é assintomático. Em humanos, no estágio final da cirrose, o transplante é o único tratamento. Desta forma, a busca por tratamentos alternativos torna-se imprescindível. A administração de fatores hepatotróficos (FH) tem sido estudada como uma alternativa de tratamento. Este estudo objetivou avaliar os efeitos dos FHs na cirrose hepática murina induzida pela tioacetamida (TAA), imediatamente após o tratamento, e 60 dias pós o seu término. 75 ratas Wistar foram subdivididas em quatro grupos; FH (n=15) e o seu grupo controle (CT, n=30), e FH+60d (n=15) e seu controle (CT, n=15); todos os animais foram induzidos à cirrose hepática pela administração TAA (200mg/Kg), ip, 3 vezes/semana, por 14 semanas. Após a indução, dois grupos receberam a solução de FHs por 12 dias. Um foi eutanasiado imediatamente após o tratamento e o outro, 60 dias após o seu término. Foram realizadas análises bioquímica sérica e histopatológica; a quantificação do colágeno; avaliação da proliferação celular e da ativação das células estreladas. Ainda, foram avaliadas a expressão gênica de proteínas envolvidas na fibrogênese, como, colágeno tipo 1, TGF-1, TIMP-1, MMP-2, MMP-13 e PLAU. Os resultados obtidos imediatamente após o tratamento mostraram que os FHs melhoraram as funções hepáticas, reduziram a deposição de colágeno e a ativação das células estreladas; alterando os mecanismos moleculares envolvidos na fibrogênese pela redução da expressão do colágeno tipo 1, aumento de TIMP-1, MMP-13 e PLAU. A maioria destes efeitos se manteve após o término do tratamento. Os resultados indicam que os FHs auxiliam no restabelecimento das funções e arquitetura hepáticas, atuando sobre os mecanismos de deposição e degradação da MEC, e que o tratamento com os FHs têm ação prolongada, não desaparecendo imediatamente após o tratamento.
Hepatic cirrhosis is an irreversible process characterized by an imbalance between deposition and degradation of extracellular matrix components (ECM). This disease leads to hepatocellular dysfunction and increased resistance to blood flow resulting in liver failure and portal hypertension. The cirrhosis, in dogs, is often identified in the final stages whereas the early stage is asymptomatic. In humans, in the final stage of the cirrhosis, transplantation is the only treatment. Thus, the search for alternative treatments becomes essential. The administration of hepatotrophic factors (HF) has been studied as a treatment alternative. This study evaluated the effects of HFs in murine liver cirrhosis induced by thioacetamide (TAA) immediately after treatment, and 60 days after it ends. 75 female Wistar rats were distributed into four groups: HF (n=15) and control group (n=30), and HF+60d (n=15) and control group (n=15). Hepatic cirrhosis was induced in all animals by TAA administration (200 mg/kg), ip, 3 times a week for 14 weeks. After induction, two groups received the HFs solution for 12 days. One group was euthanized immediately after treatment and another group was euthanized 60 days after treatment. The following analyzes were performed: serum biochemistry, histopathologic, collagen quantification, cell proliferation, and stellate cells activation. In addition, the gene expression of proteins involved in fibrogenesis such as type 1 collagen, TGF-1, TIMP-1, MMP-2, MMP-13, and PLAU was evaluated. The results found immediately after treatment showed that HFs improved liver function, and reduced collagen deposition and stellate cells activation. Alterations of the molecular mechanisms involved in fibrogenesis were observed by reducing the expression of collagen type 1 and increased expression of TIMP-1, MMP-13 and PLAU. Most of these effects remained after the treatment. The results indicate that the HFs assist in restoration of liver function and architecture, acting on the mechanisms of deposition and degradation of ECM. Furthermore, the treatment with HFs showed prolonged action, remaining during the post-treatment.

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Palma, Luana Carneiro. "Doença esteatóica não alcoólica do fígado: comparação das alterações histológicas hepáticas entre modelo murino e pacientes obesos." Centro de Pesquisas Gonçalo Moniz, 2013. https://www.arca.fiocruz.br/handle/icict/7149.

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Universidade Federal da Bahia. Salvador, BA, Brasil / Fundação Oswaldo Cruz. Centro de Pesquisas Gonçalo Moniz. Salvador, BA, Brasil
A Doença Esteatótica Não Alcoólica do Fígado (do inglês Nonalcoholic Fatty Liver Disease – NAFLD) é uma doença crônica hepática de caráter espectral, que vai desde a esteatose simples até a esteato-hepatite não alcoólica. A progressão para cirrose e carcinoma hepatocelular têm sido descrita. A NAFLD apresenta aspectos histológicos semelhantes à doença hepática relacionada ao álcool (esteatose, inflamação lobular, corpúsculos de Mallory e fibrose), mas acomete indivíduos com história negativa de consumo excessivo de álcool. A NAFLD é uma das principais doenças crônicas hepáticas mundiais, e os indivíduos obesos representam a maioria dos casos da doença. Os mecanismos envolvidos na progressão da esteatose para esteato-hepatite não são bem compreendidos. Neste aspecto, modelos murinos da NAFLD têm sido frequentemente utilizados para elucidação destes mecanismos. A maioria dos modelos disponíveis é resultante de modificações genéticas e/ou nutricionais e, em geral, não simulam as alterações metabólicas e histológicas comumente vistas em pacientes com NAFLD. Em nosso grupo, foi proposto um novo modelo de NAFLD. Camundongos C57BL/6 alimentados com dieta rica em gordura (High Fat - HF) demonstraram alterações metabólicas e histológicas sugestivas de NAFLD. O objetivo do presente trabalho foi comparar alterações histológicas hepáticas presentes nestes camundongos com as alterações observadas em pacientes obesos. Amostras de fígados de pacientes obesos e de camundongos alimentados com a dieta HF foram utilizadas. Os tecidos hepáticos foram corados em Hematoxilina & Eosina e Picrossírius Red para avaliação das alterações hepáticas (esteatose, balonização, inflamação, corpúsculos de Mallory-Denk e fibrose). Além disso, foi realizada imunoistoquímica para avaliação da presença de células estrelares ativadas e de células progenitoras hepáticas, células envolvidas na fibrose e no desenvolvimento de carcinoma hepatocelular, respectivamente. Os resultados demonstraram que os fígados de todos os pacientes obesos exibiram esteatose macrovacuolar, balonização hepatocelular, inflamação lobular e fibrose perissinusoidal, o que caracterizou estes pacientes como portadores da NAFLD. As mesmas alterações foram observadas em fígados de camundongos alimentados com a dieta HF. As células estrelares ativadas foram observadas em todos os pacientes obesos, assim como em camundongos de dieta HF. As células progenitoras hepáticas foram observadas na maioria dos pacientes obesos. O fígado de todos os camundongos alimentados com dieta HF exibiram células progenitoras hepáticas. A partir dos dados obtidos, pode-se concluir que fígados de camundongos alimentados com dieta HF exibem alterações histológicas hepáticas similares às observadas em pacientes obesos. Isto abre perspectivas para a utilização do modelo proposto em estudos que busquem elucidar os mecanismos envolvidos na patogênese da NAFLD.
Nonalcoholic Fatty Liver Disease (NAFLD) is a chronic liver disease ranging from simple steatosis to nonalcoholic steatohepatitis. The progression to cirrhosis and hepatocellular carcinoma has been reported. The NAFLD shows histological features similar to alcohol-related liver disease (steatosis, lobular inflammation, fibrosis and Mallory-Denk bodies), but affects individuals with no history of excessive alcohol consumption. The NAFLD is a major chronic hepatic disease in the world, and obese individuals represent the majority of cases of the disease. The mechanisms involved in the progression of steatosis to steatohepatitis are not well understood. In this regard, murine models of NAFLD have been frequently used for elucidation of these mechanisms. Most available models are the result of genetic or nutritional modifications, and generally do not mimic metabolic and histologic changes commonly seen in patients with NAFLD. In our group, we have proposed a new model of NAFLD. Mice fed high fat diet (HF diet) demonstrated metabolic and histological features suggestive of NAFLD. The aim of this study was to compare liver histological alterations present in these mice with the changes observed in obese patients. Samples of livers of obese patients and mice fed HF diet were used. For assessment of liver alterations, such as steatosis, ballooning, inflammation, Mallory- Denk bodies and fibrosis, tissues were stained with hematoxylin & eosin and picrossirius red. In addition, the presence of activated stellate and progenitor liver cells was estimated using immunohistochemistry. The results show that the livers of all obese patients exhibited macrovesicular steatosis, hepatocellular ballooning, perisinusoidal fibrosis, and lobular inflammation, which characterized these patients with NAFLD. Similar changes were observed in livers of mice that fed the HF diet. Activated stellate cells were observed in all obese patients as well as in mice HF. Hepatic progenitor cells were observed in most obese patients. The liver of all animals fed the HF diet exhibited liver progenitor cells. From the data obtained, it can be concluded that livers of mice fed with HF diet exhibit liver abnormalities similar to those observed in obese patients. This opens perspectives for the use of the proposed model in studies that seek to elucidate the mechanisms involved in the pathogenesis of NAFLD.

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Royer, Moës Anne Escande Denis. "Canalopathies cardiaques et modèles murins." [S.l.] : [s.n.], 2004. http://theses.univ-nantes.fr/thesemed/DOCroyer.pdf.

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Leoni, Anne-Laure Escande Denis. "Modèles murins en rythmologie expérimentale." [S.l.] : [s.n.], 2006. http://castore.univ-nantes.fr/castore/GetOAIRef?idDoc=38466.

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Leoni, Anne-Laure. "Modèles murins en rythmologie expérimentale." Nantes, 2006. http://archive.bu.univ-nantes.fr/pollux/show.action?id=538b454d-5553-4cc8-8af0-c8f22d052097.

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L’activité électrique cardiaque prend naissance dans le nœud sinusal et se propage au myocarde contractile grâce au tissu de conduction. Le travail exposé dans cette thèse démontre le rôle de deux sous-unités de canaux ioniques dans l’automatisme des cellules sinusales et la conduction de l’influx électrique dans le cœur, grâce à l’utilisation de modèles murins. Le premier confirme in vivo l’hypothèse selon laquelle le canal calcique de type T, Cav3. 1, participe à l’automatisme du nœud sinusal et démontre son implication dans la conduction auriculo-ventriculaire (AV) de l’influx électrique. Dans un second, l’invalidation du canal sodique Nav1. 5 (Scn5a+/-) conduit à une dysfonction sinusale, des troubles de conduction AV et intra-ventriculaires identiques à ceux observés chez des patients porteurs de mutations du gène SCN5A. Ce modèle reproduit fidèlement l’hétérogénéité phénotypique existant chez les patients, suggérant l’importance de gènes modulateurs ou de l’environnement dans le phénotype des maladies génétiques. Enfin, la modulation du rythme constituant un enjeu majeur en thérapeutique cardiaque, nous avons montré que l’inhibition chronique des canaux pacemaker HCN induisait un remodelage ionique sinusal mais avait peu d’effet sur l’expression des canaux ioniques dans le ventricule chez la souris
Cardiac impulse originates from the sinus node and propagates through the cardiac conduction system to depolarise atrial and ventricular myocardium. The work exposed herein reveals the implications of two ion channel subunits in sinus node automaticity and in cardiac electrical conduction by the use of mouse models. The first model confirms the hypothesis implicating the calcium channel subunit Cav3. 1 in sinus node automaticity, and shows its implication in atrioventricular (AV) conduction. The second model shows that heterozygous invalidation of Nav1. 5 sodium channel subunit (Scn5a+/- mice) induces sinus node dysfunction, impaired AV conduction and delayed intramyocardial conduction. These cardiac abnormalities are similar to the phenotype observed in patients with SCN5A mutations. Moreover, Scn5a+/- mice showed phenotype heterogeneity, just as in patients, revealing the importance of modulator genes or environment in the phenotype of genetic disorders. Finally, as cardiac rhythm modulation is of major interest in cardiac therapeutics, we have shown that chronic inhibition of HCN channels induces a complex ionic remodelling in the sinus node, but has little impact on ion channel expression in the mouse ventricle

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Royer, Moës Anne. "Canalopathies cardiaques et modèles murins." Nantes, 2004. http://www.theses.fr/2004NANTA001.

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Les "canalopathies" cardiaques sont des maladies d'origine congénitale ou acquise associées à des dysfonctionnements des canaux ioniques. Cette thèse est consacrée à l'étude de deux modèles transgéniques murins. L'intérêt de la transgenèse réside dans le fait que l'expression et la fonction des gènes peuvent être étudiées in vivo. Le premier modèle consiste en la sur-expression du canal humain HERG au niveau cardiaque chez !a souris. L'étude de ce modèle a pour la première fois mis en évidence que l'expression de canal HERG a des effets antiarythmiques in vivo. Le second est l'étude de souris invalidées pour le gène Scn5a. Ces souris hétérozygotes présentent une réduction de 50% de leur courant sodique et des troubles de conduction, s'aggravant avec l'âge, associés à un processus scléreux dégénératif. Ce modèle murin présente toutes les caractéristiques phénotypiques de la maladie de Lenègre
Cardiac channelopathies are inherited or acquired diseases linked to ionic channel dysfonction. This thesis is about two transgenic murine models. The interest of transgenese is that gene expression and function can be study in vivo. The first murine model overexpresses the human HERG channel in the mouse heart. Its study has shown for the first time antiarrhythmic effects of HERG expression in vivo. The second murine model is a knock-out of Scn5a gene. Heterozygous mice have a 50 % reduction in their cardiac myocytes Na+ current and exhibit cardiac conduction defects. These cardiac conduction defects worsen with age and are associated with fibrosis. Scn5a +/- mice are a convincing model for Lenègre's disease

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Hüttemann, Maria. "Licht- und elektronenmikroskopische Untersuchungen an Entwicklungsstadien von Angiostrongylus cantonensis und Trichuris muris (Nematodes)." [S.l. : s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=97184397X.

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Gautret, Philippe. "Le phénomène de Hawking chez les Plasmodium de muridés." Paris 12, 1996. http://www.theses.fr/1996PA120025.

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L'etude morphologique et biologique des gametocytes des plasmodium de murides africains fait apparaitre les faits suivants: l'induction d'une hyper-reticulocytose chez la souris par la phenylhydrazine augmente la production de gametocytes par p. Chabaudi et p. Berghei. Elle est sans effet sur les gametocytes de p. Vinckei et p. Yoelii. Pour tous les plasmodium etudies, de nouveaux gametocytes sont produit a chaque schizogonie, le rythme de production des stades sexues depend donc de celui des stades asexues. Pour p. V. Vinckei et p. V. Petteri, la duree de maturation des merozoites en gametocyte de type 0 est de 27 heures. Le type 0 se transforme en type i en 3 heures, le type i en type ii en 6 heures et le type ii en type iii en 3 heures. Pour p. Chabaudi, la duree de maturation d'un merozoite en gametocyte de stade 0 est de 36 heures. Le type 0 se transforme en type i en 6 heures, le type i en type ii en 6 heures et le type ii en type iii en 6 heures. Pour p. Y. Nigeriensis et p. Y. Yoelii, la maturation d'un merozoite en gametocyte de type 0 s'effectue en 27 heures. Les gametocytes de type 0 evoluent en type i en 6 heures, les types i se transforment en type ii en 3 heures puis il faut encore 3 heures pour que les types ii evoluent en type iii. Pour p. V. Petteri, le gametocyte de type ii est le stade infectant et l'infectivite pour le moustique s'effectue selon un rythme de 24 heures. Elle est maximale en periode interschizogonique. Pour p. Chabaudi, le gametocyte de type ii est egalement le stade infectant mais du fait que sa periode de maturation est contemporaine de la schizogonie, l'infectivite pour l'anophele ne presente pas de variation nycthemerale. Pour p. Y. Yoelii, le gametocyte de type 0 est le stade infectant. Du fait qu'un nombre non negligeable de merozoites penetre tardivement dans les hematies, l'infectivite pour l'anophele ne presente pas de variation nycthemerale lorsque l'infection est synchronisee par le percoll-glucose. Pour les trois plasmodium, le stade infectant est sequestre dans les fins capillaires ou il est preleve plus facilement par le moustique

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Grippo, Mariangela Carnivalli. "Identificação e caracterização de um coronavirus murino (MHV-CAM) atraves da comparação com o virus da hepatite murina tipo 3." [s.n.], 2002. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316958.

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Orientador : Liana Verinaud
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
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Fercoq, Frédéric. "Interactions filaire/poumon dans le modèle murin de filariose Litosomoides sigmodontis." Thesis, Paris, Muséum national d'histoire naturelle, 2017. http://www.theses.fr/2017MNHN0018/document.

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Les filaires sont des nématodes parasites transmis à des vertébrés par des arthropodes hématophages. Les espèces filariennes qui s'installent dans les cavités cœlomiques, les vaisseaux lymphatiques ou des tissus conjonctifs ont leurs stades infestants (ou L3) qui migrent via le système lymphatique après leur inoculation dans la peau. En utilisant le modèle murin avec la filaire Litomosoides sigmodontis dont les adultes résident dans la cavité pleurale, deux phases d'interaction des filaires avec les poumons des souris BALB/c sont décrites 1) lors de la migration des L3 de la peau à la cavité pleurale ; 2) pendant la phase patente de l’infection quand les adultes pondent des microfilaires dans la cavité pleurale. Dans la 1ère phase les L3 rejoignent le système sanguin pulmonaire puis traversent les poumons pour entrer dans la cavité pleurale. Ce passage induit une pathologie aigue transitoire: tout d'abord des hémorragies consécutives à la rupture des capillaires pulmonaires, accompagnées d'une augmentation du nombre de neutrophiles pulmonaires et de la libération transitoire d'IL-1β et des alarmines IL-33 et S100A9 dans la cavité pleurale. Le S100A9 semble faciliter la survie des filaires, soit par un effet anti-inflammatoire soit en facilitant la migration des L3. Les neutrophiles peuvent libérer des NETS en réponse aux L3. Dans les jours suivant l'infection, une réponse régulatrice se met en place dans les poumons, avec le recrutement de macrophages et d'éosinophiles, la production d'IL-4, de CCL2 et d'IL9, ainsi que la baisse d'expression de molécules inflammatoires. La formation des granulomes est également observée dans le tissu pulmonaire. Le passage des L3 induit aussi une inflammation des vaisseaux sanguins pulmonaires chez les souris C57BL/6 seulement. Lors de la phase patente de l'infection, 40% des souris ne développent pas de microfilarémie sanguine. La comparaison des réponses des souris microfilarienne et amicrofilarienne montre une exacerbation de l'inflammation pleurale induite par les microfilaires. De plus, les souris microfilarémiques développent une pathologie pulmonaire dépendant des microfilaires consistant en la fibrose de la plèvre viscérale, une accumulation périvasculaire de macrophages et une inflammation bronchoalvéolaire (production de mucus et éosinophilie). Le contrôle des filaires (adultes et microfilaires), mais aussi la mise en place de la pathologie sont dépendantes de l'IL-5 et de l'IL-4R
Filariae are parasitic nematodes transmited to vertebrates by haematophagous arthropods. The filarial species that settle in the coelomic cavities, the lymphatic vessels or the connective tissues have their infectious stages (or L3) which migrate via the lymphatic system after their inoculation into the skin. Using the murine model with the filaria Litomosoides sigmodontis, whose adults reside in the pleural cavity, two phases of interaction between filariae and the lung of BALB/c mice are described 1) during the L3 migration from the skin to the pleural cavity ; 2) during the patent phase of infection, when adults realease microfilariae in the pleural cavity. During the 1st phase L3 join the pulmonary blood system and then cross through the lungs to enter the pleural cavity. This passage induces a transient acute pathology: first haemorrhages following the rupture of the pulmonary capillaries, together with an increase in the number of pulmonary neutrophils and the transient release of IL-1β and the alarmins IL-33 and S100A9 in the pleural cavity. S100A9 appears to facilitate the survival of the filariae either by an anti-inflammatory effect or by facilitating the migration of L3. Neutrophils can release NETs in response to L3. Within days following the infection, a regulatory response takes place in the lungs, with recruitment of macrophages and eosinophils, production of IL-4, CCL2 and IL-9, and downregulation of inflammatory molecules. The formation of granulomas is also observed in pulmonary tissue. The passage of L3 also induces an inflammation of pulmonary blood vessels, in C57BL/6 mice only. During the patent phase of the infection, 40% of the mice do not develop blood microfilaraemia. Comparison of responses of microfilaremic and amicrofilaremic mice shows an exacerbation of pleural inflammation induced by microfilariae. In addition, microfilaremic mice develop microfilaria-dependent pulmonary pathology consisting on fibrosis of the visceral pleura, perivascular accumulation of macrophages and bronchoalveolar inflammation (mucus production and eosinophilia). The control of the filariae (adults and microfilariae), but also the establishment of the pathology are dependent on IL-5 and IL-4R

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Sanlaville, Amélien. "Rôle de la réponse immunitaire adaptative anti-tumorale dans l’induction de la transition épithélio-mésenchymateuse." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSE1276.

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Un enjeu majeur en cancérologie est de réduire le risque de développement métastatique et de rechute. La transition épithélio-mésenchymateuse (EMT), processus physiologique au cours de l'embryogenèse, est un mécanisme central de la carcinogenèse, contribuant de façon précoce à la transformation et la dissémination des cellules tumorales via l'inhibition de la surveillance cellulaire (apoptose et senescence) et l'acquisition de capacités migratoires et invasives. Une autre caractéristique des cancers est la capacité d'échapper à la réponse immunitaire, puissante barrière anti-tumorale. Mais les cellules tumorales entretiennent des relations complexes avec le système immunitaire. Alors que la propension de l'inflammation et des cellules immunitaires innées à favoriser le développement tumoral et l'échappement immunitaire, via l'induction de l'EMT et le maintien d'un microenvironnement immuno-suppresseur, a été bien étudiée, le rôle éventuel de la réponse immunitaire adaptative dans la promotion de l'EMT est quant à lui peu connu. Grâce au développement d'un modèle murin de lignée tumorale mammaire plastique surexprimant l'oncogène Her2/Neu, ce travail démontre in vivo la capacité des cellules tumorales à subir l'EMT, induite par la réponse immunitaire médiée par les lymphocytes T. La déplétion spécifique des lymphocytes T (LT) CD4 restaure le phénotype épithélial de la tumeur, indiquant que les LT CD4 médient une réponse immunitaire induisant l'EMT. En retour, l'EMT confère aux cellules tumorales la capacité de modeler l'immunité comme le recrutement de neutrophiles. Ce travail apporte un nouvel éclairage sur les interactions entre cellules tumorales et système immunitaire
Current clinical challenge in many carcinomas is to reduce the risk of metastasis development and cancer recurrence. Epithelial-mesenchymal transition (EMT), a physiological process during embryogenesis, is a central mechanism in oncogenesis. EMT induction contributes to early transformation and dissemination through inhibition of cellular surveillance (apoptosis and senescence) and increased migrative and invasive behavior. Another necessary hallmark of cancer is the ability of tumor cells to evade immune surveillance, a powerful barrier against tumor progression. But cancer cells enjoy intricate relations with the immune system. Whereas inclination of inflammation and innate immune cells to favor tumor development and immune escape, via EMT induction and immunosuppressive microenvironment maintenance, has been well investigated, the role of adaptive immune response in EMT promotion is understudied. Based on the development of a plastic murine mammary tumor cell line model overexpressing Her2/Neu oncogene, this study demonstrate in vivo that tumor cells keep an epithelial phenotype in adaptive immunodeficient mice but undergo EMT under the pressure of T-cell mediated immune response, characterized by loss of epithelial EpCAM marker and acquisition of mesenchymal features and EMT transcriptomic signature. CD4 T cell depletion but not CD8 restores the epithelial phenotype of tumors, suggesting that CD4 T cells mediate an immune response that could lead ton EMT induction. In return, EMT confers the ability of tumor cells to shape immunity like intra-tumor neutrophil infiltration. This work shed a new light on interactions between tumor cells and immune system

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Nengovhela, Aluwani. "3D cranial morphometry, sensory ecology and climate change in African rodents." Thesis, Toulouse 3, 2018. http://www.theses.fr/2018TOU30307.

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L'ordre des rongeurs (Rodentia) est le groupe de mammifères le plus riche en espèces, les muroïdes étant la superfamille la plus diversifiée. Comme ils occupent des niches écologiques arboricoles, semi-aquatiques, souterraines et terrestres, les rongeurs peuvent présenter des traits morphologiques reflétant leurs adaptations à des environnements aussi divers. Cette thèse porte sur la morphologie de l'endocrâne, de la bulle auditive et de la cochlée dans trois tribus (Otomyini, Taterillini et Gerbillini) représentant 10 espèces de rongeurs africains, en se concentrant sur la variabilité de ces traits, leur fonction et leur adaptabilité, à l'aide d'imagerie par micro-scanner et de méthodes de comparaison de formes tridimensionnelles. De plus, les variations de la taille du crâne ont également été étudiées en fonction du réchauffement climatique et des variables climatiques. Les changements / variations morphologiques sont liées à des différences environnementales. Par conséquent, chaque chapitre de cette étude détaille l'effet des changements environnementaux (dans l'espace et dans le temps) sur différents traits morphologiques, c'est-à-dire la taille générale du crâne (chapitre 2), la cochlée et les bulles auditives (chapitre 3), et la taille et la forme endocrânienne (chapitre 4). Le chapitre 2 traite spécifiquement du changement climatique au sens strict et les deux autres chapitres traitent de différents gradients environnementaux. Le chapitre 2 teste l'applicabilité de la "troisième réponse universelle au réchauffement" (c'est-à-dire de la diminution de la taille corporelle) et de la "règle des ressource" dans deux sous-familles de muridés, Murinae et Gerbillinae. L'étude montre que la troisième réponse n'est pas universelle puisqu'une seule espèce s'est conformée à ce type de réponse. De plus, il a été démontré que la disponibilité de nourriture (règle des ressources) était un facteur plus important que la règle de Bergmann pour expliquer les corrélations entre variations de l'environnement et celles de la taille des espèces de rongeurs.[...]
The order Rodentia is the most speciose group of mammals with muroids being the most diverse superfamily. Since they are represented in arboreal, semiaquatic, subterranean and terrestrial niches, rodents may exhibit morphological traits reflecting their adaptations to such diverse environments. This thesis focuses on the morphology of the endocranium, auditory bulla and cochlea in three tribes (Otomyini, Taterillini and Gerbillini) representing 10 species of African rodents, concentrating on their variability, function and adaptability, using micro-CT imaging and 3D shape comparative methods. Additionally, variations in cranial size were also studied in respective of global warming and climatic variables. Morphological changes/variations are a result of environmental change, therefore each chapter in this study details the effect of environmental change (in space and time) on different morphological traits i.e. general cranial size (chapter 2), cochlea and auditory bulla (chapter 3) and endocranial size and shape (chapter 4). With chapter 2 dealing specifically with climate change in its straict sense and the remaining two chapters looking at different environmental gradients. Chapter 2 tests the applicability of the "third universal response to warming" (i.e. declining body size) and the Resource Rule in two murid subfamilies, Murinae and Gerbillinae. The study shows that the third response is not as universal as only one species conformed to this response. Further, food availability (Resource Rule) was shown to be the more important factor correlated with body size variations in rodent species than Bergmann's Rule. [...]

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Schwarz, David Germano Gonçalves. "Distribuição de Mycobacterium avium subespécie paratuberculosis em órgãos de camundongos C57BL/6 experimentalmente infectados." Universidade Federal de Viçosa, 2012. http://locus.ufv.br/handle/123456789/5166.

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Mycobacterium avium subspecies paratuberculosis (MAP) is the etiological agent of paratuberculosis, a disease which causes chronic granulomatous enteritis preferably in domestic and wild ruminants. It is characterized by intermittent diarrhea, progressive weight loss and reduced milk production. The major route of transmission is the ingestion of food and water contaminated by feces of infected animals. It is considered a disease of high economic importance, because of losses in livestock and importance in human health, since there is evidence of possible correlation of MAP with Crohn's disease. Although previous researches have contributed to advances in the diagnosis of subclinical MAP in animals, there is a lack of studies concerning the correct understanding of its pathophysiology. Thus, the aim of this study was to investigate the distribution of MAP by means of the histology and nested-PCR techniques in organs of C57BL/6 mice infected with MAP66115-98 strain at a dose of 3 x 108 CFU /mL intraperitoneally (IP). It was applied 250μl of inoculum in 20 mice, and it was applied saline phosphate buffer (PBS) in eight control species. The animals were euthanized at 30, 60, 90 and 120 days post-inoculation, and fragments of spleen, liver, colon, ileum and Peyer's patches of five mice and two control, for each period of time, were performed molecular and histopathological evaluations. Although it was not found histologic lesions in sections stained by Hematoxylin Eosin, there was a positive staining for two Peyer s patches referring to 90 and 120 days after inoculation, stained by Ziehl-Neelsen. Among the collected organs, 64.9% were positive by molecular technique. The spleen (0.85), colon (0.75) and liver (0.60) had the highest proportion of positive regardless of the evaluation period. Taking into consideration the time after inoculation, the spleen had a higher proportion of positive results after 60 days of infection (1.00), remaining stable until 120 days. The colon had a higher proportion at 30 days (1.00) and drastically reduced to 90 days (0.40). The liver ranged between 0.40 and 0.80 during the four periods of evaluation and the Ileum showed positivity ratio equal to 0.80 only at 120 days of infection. Moreover, Peyer's patches did not vary significantly (0.40) from day 60, remaining with the lowest ratio among the organs studied. The assessment of the probability of infection of an organ relative to another was obtained by the Relative Risk, where the highest values were observed in the ratio of spleen/Peyer's patches (2.00), colon/Peyer's patches (1.74), spleen/ileum (1.54) and spleen/liver (1.40). The highest odds ratio values were observed in the spleen/Peyer s patches (7.56), spleen/ileum (4.64), spleen/liver (3.78), and colon/ileum (2.45). However, among all the established associations, only the relations spleen / ileum and spleen / Peyer's patches were statistically significant at the level of 95%, showing that the spleen was the organ with higher risk and chances of positivity in relation to the ileum and Peyer's patches. Thus, these results can contribute to better understanding of the distribution of MAP in experimental models during the course of systemic infection, being this the first study to correlate the infective capacity of the strain MAP66115- 98 in C57BL/6 mice with a distribution in different organs after inoculation by intraperitoneal route.
Mycobacterium avium subespécie paratuberculosis (MAP) é o agente etiológico da paratuberculose, uma enfermidade que causa enterite granulomatosa crônica preferencialmente em ruminantes domésticos e silvestres. É considerada uma doença de impacto na economia, devido às perdas no rebanho e na saúde humana, uma vez que se têm indícios da possível relação de MAP com a doença de Crohn. Embora pesquisas tenham contribuído para avanços no diagnóstico de MAP, há carências de estudos relacionados à compreensão de sua patofisiologia. Desse modo, este estudo propôs avaliar a distribuição de MAP por meios das técnicas de nested-PCR e histologia em órgãos de camundongos C57BL/6 infectados por via intraperitoneal com a cepa MAP66115-98. Em 20 camundongos foram aplicados 250μl de inóculo contendo 3 x 108 UFC/mL e, em oito controles foram aplicados tampão fosfato-salina (PBS). Os animais foram eutanasiados aos 30, 60, 90 e 120 dias pós-inoculação. Em cada período, foram coletados baço, fígado, cólon, íleo e placas de Peyer de cinco camundongos desafiados e dois controles. O material foi dividido para avaliação molecular e histopatológica. Embora não tenham sido verificadas alterações histológicas nas lâminas coradas pela Hematoxilina Eosina, houve marcação positiva para duas placas de Peyer, referentes a 90 e 120 dias pós-inoculação, quando coradas pela técnica de Ziehl-Neelsen. Dentre os órgãos coletados, 64,9% foram positivos pela técnica molecular. Os órgãos que apresentaram maiores valores proporcionais de positividade independentemente do período de avaliação foram o baço (0,85), o cólon (0,75) e o fígado (0,60). Ao levar em consideração o tempo pós-inoculação, o baço apresentou maior proporção de positividade após 60 dias (1,00), permanecendo estável até os 120 dias, enquanto o cólon apresentou maior proporção aos 30 dias (1,00) e reduziu drasticamente aos 90 dias (0,40) da inoculação. O fígado variou entre 0,40 e 0,80 durante os quatro períodos de avaliação e o Íleo apresentou proporção de positividade igual a 0,80 apenas aos 120 dias de inoculação. Por outro lado, as placas de Peyer não variaram significativamente a partir dos 60 dias (0,40) permanecendo com a menor proporção dentre os órgãos analisados. A avaliação da probabilidade de infecção de um órgão em relação a outro foi obtida pelo Risco Relativo, onde os maiores valores foram verificados na relação entre baço/placas de Peyer (2,00); cólon/placas de Peyer (1,74); baço/íleo (1,54) e baço/fígado (1,40). Os maiores valores de Razão de Chances foram verificados na relação entre baço/placas de Peyer (7,56); baço/íleo (4,64); baço/fígado (3,78) e cólon/íleo (2,45). Contudo, dentre todas as associações estabelecidas, apenas as relações: baço/íleo e baço/placas de Peyer foram estatisticamente significativas à nível de 95%, demonstrando que o baço foi o órgão com maior risco e chances de positividade em relação ao íleo e placas de Peyer. Assim, estes resultados podem contribuir para a melhor compreensão da distribuição de MAP em modelos experimentais durante o curso de uma infecção sistêmica, sendo o primeiro trabalho a correlacionar a capacidade infectiva da cepa MAP66115-98 nos camundongos C57BL/6 com a sua distribuição em diferentes órgãos pós-inoculação usando a via intraperitoneal.

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Lopes, Alan de Aguiar. "Estudos dos efeitos antioxidantes e anti-inflamatórios da própolis sobre as células RAW 264.7 e na resposta inflamatória pulmonar aguda causada pela exposição à fumaça de cigarro em camundongos." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=5927.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
A doença pulmonar obstrutiva crônica (DPOC) causa a redução da capacidade respiratória e seu desenvolvimento é associado à fumaça de cigarro. O cigarro possui mais de 4800 substâncias tóxicas e causa a morte de seis milhões de pessoas por ano no mundo. Estudos buscam meios de reverter os males causados pela fumaça de cigarro. A própolis (P) é um produto produzido por abelhas que possui várias propriedades. O objetivo deste trabalho foi avaliar os efeitos antioxidantes da P em macrófagos murinos e na inflamação pulmonar aguda induzida pela fumaça de cigarro (CS) em camundongos. A análise dos compostos fitoquímicos do extrato alcóolico da P (EAP) foi feita por cromatografia gasosa acoplada à espectrometria de massa (GC-MS). Células da linhagem RAW 264.7 foram tratadas em diversas concentrações de P durante 24 horas. Após tratamento, as seguintes análises foram realizadas: polifenóis totais; viabilidade celular (MTT); potencial redutor (DPPH); espécies reativas de oxigênio totais (ROS) e de malondialdeído (MDA). Trinta camundongos C57BL/6 foram divididos em 3 grupos (n=10/grupo): Controle+P, CS e CS+P. Ambos os grupos CS foram expostos a 6 cigarros/dia durante 5 dias. O grupo CS foi tratado com veículo. O pulmão e o lavado broncoalveolar (BAL) foram coletados para análise histológica e contagem diferencial de células. As análises para mieloperoxidase (MPO), superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa reduzida (GSH) e oxidada (GSSG), MDA, nitrito e western blotting para TNF-alfa foram realizadas. A análise fitoquímica do EAP mostrou a presença dos ácidos hidrocinâmicos e coumárico, a artepilina C e a drupanina. Foi observado o aumento concentração-dependente dos níveis de polifenóis totais (p<0,001), do MTT (p<0,001) e do DPPH (p<0,001), e o inverso com o MDA (p<0,001). Os níveis de ROS diminuem nas concentrações de 15,6 e 31,2 mg/mL (p<0,05, ambos). A histologia pulmonar do grupo Controle+P foi similar ao do CS+P e foi observado um influxo de macrófagos e neutrófilos no grupo CS (p<0,01 e p<0,001, respectivamente). Os níveis de MPO foram aumentados no grupo CS (526,534,72 mU/mg ptn, p<0,01), mas houve uma redução no grupo CS+P (385,127,64 mU/mg ptn, p<0,05) comparável ao Controle+P (13412,99 mU/mg ptn, p<0,001), o mesmo aconteceu com as enzimas antioxidantes: SOD (Controle+P: 523,529,6 U/mg ptn; CS: 523,529,6 U/mg ptn, p<0,001; CS+P: 246,815,69 U/mg ptn, p<0,001); CAT (Controle+P: 37,383,39 U/mg ptn; CS: 92,686,24 U/mg ptn, p<0,001; CS+P: 59,844,55 U/mg ptn, p<0,05); GPx (Controle+P: 2,230,17 (M/min/mg ptn) x 10-1; CS: 4,510,31 (M/min/mg ptn) x 10-1, p<0,001; CS+P: 2,640,19 (M/min/mg ptn) x 10-1, p<0,05). O inverso ocorreu com a relação GSH/GSSG (Controle+P: 1,0880,17; CS: 0,7360,07, p<0,05; CS+P: 1,2580,10, p<0,05). Os níveis de MDA (Controle+P: 0,2660,05 nMol/mg ptn; CS: 0,940,076 nMol/mg ptn, p<0,001; CS+P: 0,4980,06 nMol/mg ptn, p<0,01) e de nitrito (Controle+P: 50,014,19 Mol/mg ptn; CS: 108,77,73 Mol/mg ptn, p<0,001; CS+P: 58,843,42 nMol/mg ptn, p<0,01) estavam aumentados no CS que em outros grupos. A expressão de TNF-α foi observada no grupo CS. O tratamento da P apresentou ação anti-inflamatória e antioxidante em macrófagos e em camundongos expostos à fumaça de cigarro, possivelmente pela ação dos polifenóis presentes nela
Chronic obstructive pulmonary disease (DPOC) causes a respiratory capacity reduction and its development is be associated with cigarette smoke. Cigarette has more than 4800 toxic substances in your composition and it causes death of six million people in the world. Studies had been made to find methods to change cigarette-induced health problems. Propolis (P) has been reported as a natural product with several properties. Here, we used two types of experiments, in vitro and in vivo, to study the potential antioxidant use of P. Phytochemical analyze was made to evaluate which compounds are within P. Murine macrophages, RAW 264.7 cell line, are exposed to different concentrations of propolis and following analyses were made: total polyphenols levels; cell viability (MTT); reduction potential (DPPH); total reactive oxygen species levels (ROS) and malondialdehyde (MDA). Thirty C57BL6 mice were divided into 3 groups: Control+P, CS and CS+P. Both CS groups were exposed to 6 cigarettes per day for 5 days. CS group was treated with vehicle. Lung and bronchoalveolar lavage (BAL) were collected for histological analysis and differential cell counts. Analysis for mieloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), oxidized glutathione (GSSG), MDA, nitrite and western blotting for TNF-alpha were performed. Phytochemical analyses of P showed which possesses four main compounds: hydrocinnamic and coumaric acids; artepillin C and drupanin. P showed an increase in total polyphenols (p<0.001), cell viability (p<0.001) and DPPH levels (p<0.001) in concentration-dependent manner, different from MDA (p<0.001) which was inverse pattern. P decreased ROS levels in 15.6 and 31.2 mg/mL groups (p<0.05). Lung histology of Control+P group was similar to CS and CS+P groups, however significant inflammatory cell influx was observed in CS group. Propolis administration reduced significantly macrophages and neutrophils compared with CS group (p<0.01 e p<0.001, respectively). MPO levels was increased in CS (526.534.72 mU/mg ptn, p<0.01), but was shown to be reduced in CS+P (385.127.64 mU/mg ptn, p<0.05) compared with Control+P (13412.99 mU/mg ptn, p<0.001), similar pattern was found in antioxidant enzymes: SOD (Controle+P: 523.529.6 U/mg ptn; CS: 523.529.6 U/mg ptn, p<0.001; CS+P: 246.815.69 U/mg ptn, p<0.001), CAT (Controle+P: 37.383.39 U/mg ptn; CS: 92.686.24 U/mg ptn, p<0.001; CS+P: 59.844.55 U/mg ptn, p<0.05) and GPx (Controle+P: 2.230.17 (M/min/mg ptn) x 10-1; CS: 4.510.31 (M/min/mg ptn) x 10-1, p<0.001; CS+P: 2.640.19 (M/min/mg ptn) x 10-1, p<0.05) and different from GSH/GSSG ratio (Controle+P: 1.0880.17; CS: 0.7360.07, p<0.05; CS+P: 1.2580.10, p<0.05). MDA (Controle+P: 0.2660.05 nMol/mg ptn; CS: 0.940.076 nMol/mg ptn, p<0.001; CS+P: 0.4980.06 nMol/mg ptn, p<0.01) and nitrite levels (Controle+P: 50.014.19 Mol/mg ptn; CS: 108.77.73 Mol/mg ptn, p<0.001; CS+P: 58.843.42 nMol/mg ptn, p<0.01) increased in CS group when compared with other groups. TNF-α expression was observed in CS only. P administration showed an antioxidant action in murine macrophages and reduced cigarette smoke-induced lung inflammation and oxidative stress, probably, by action of its phytochemical compounds actions

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Agbulut, Onnik. "Modeles murins mimant des maladies neuromusculaires." Paris 7, 2001. http://www.theses.fr/2001PA077002.

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Les mutants de souris presentant une modification genetique procurent des renseignements essentiels pour comprendre le role joue par les proteines codees par le gene, et les mecanismes physiopathologiques impliques dans des maladies chez l'homme. L'objectif de mon travail est de participer a l'elaboration de nouveaux mutants correspondant a certaines atteintes neuromusculaires. Les deux modeles animaux presentes dans ce travail sont le mutant dystrophique sans desmine, et le mutant de la dystrophie myotonique. La desmine est un constituant des filaments intermediaires et un marqueur musculaire precoce. Afin de mieux comprendre le role joue par la desmine dans le developpement et la regeneration du muscle squelettique, une lignee de souris mutantes sans desmine a ete etablie (li et coll. , 1996). Nos resultats montrent que la desmine ne modifie pas la differenciation et la fusion des myoblastes mais qu'elle joue un role essentiel pour maintenir la structure de la fibre musculaire et ainsi la force musculaire. La dystrophie myotonique est une maladie genetique autosomique dominante associant des atteintes musculaires et des anomalies multisystemiques. Le defaut moleculaire de la dystrophie myotonique correspond a l'amplification d'un trinucleotide ctg repete situe dans le gene de la dmpk. Plus cette sequence est repetee, plus la maladie est grave. Des mutants de souris ont ete mis au point par l'equipe du pr c. Junien. En fonction du nombre de repetitions de ctg inserees chez les souris, nous avons analyse les perturbations du programme musculaire. Les souris portant une amplification de 300 ctg donnent les resultats les plus interessants : une atrophie des fibres lentes, des noyaux centraux et une myotonie. La comparaison

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VIALE, ANNE-CLAIRE. "Lymphocytes b murins : origine et devenir." Paris 6, 1992. http://www.theses.fr/1992PA066629.

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Nous etudierons la regulation de l'expression des familles de genes vh dans des souris congeniques pour le locus igh. Cette expression par les cellules b spleniques immunocompetentes est dictee par l'haplotype igh chez le nouveau-ne et par le fond genetique chez l'adulte. Cependant, les plasmocytes spleniques adultes ont une expression dictee par l'haplotype igh, comme les cellules b du nouveau-ne. Des souris irradiees et reconstituees avec des precurseurs lymphoides b de foie ftal ou de moelle osseuse adulte montrent que la regulation differe entre ces precurseurs. Des chimeres de moelle osseuse de f1 dans un parent montrent que l'environnement cellulaire de l'hote ne peut pas induire cette regulation et l'expression des familles de genes vh par les cellules b de souris f1, triees selon l'allotype mu exprime, montre une regulation en cis. Le phenotype d'une souris congenique igh adulte montre que les plasmocytes naturels proviennent de precurseurs perinataux differents des precurseurs medullaires des cellules b au repos et des precurseurs des cellules b1. Cette regulation montre une correlation entre l'origine des precurseurs b et l'etat d'activation des cellules b. De plus, nous montrerons que la persistance ces lymphocytes b au repos est liee a la specificite de leurs immunoglobulines. Ceci montre une survie selective des lymphocytes b en absence de toute activation cellulaire ulterieure. Nous montrerons aussi que le renouvellement de cellules b monoclonales est plus eleve que celui de cellules b polyclonales. Finalement, nous montrerons que les repertoires b peripheriques de souris axeniques conservent une expression preferentielle des familles de genes vh d-proximales, caracteristique des stades precoces de l'ontogenese et de la lymphopoiese normales. Et nous montrerons que les immunoglobulines seriques normales, injectees a des souris axeniques, participent a la selection des repertoires b peripheriques, montrant une interaction constante entre les cellules b au repos et naturellement activees

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Else, Kathryn J. "Immunogenetics of Trichuris muris infection." Thesis, University of Nottingham, 1989. http://eprints.nottingham.ac.uk/12875/.

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Investigations have been made into the genetic control of immunity to the nematode Trichuris muris. Both background genes and genes within the mouse major histocompatibility complex (MHC), H-2, were shown to influence the expulsion of T. muris with the former having the stronger influence. At least two genes within the H-2 complex determined response phenotypes, the effects of "resistance" or "susceptibility" alleles at I-A being modulated by resistance or susceptibility alleles at aD end locus/loci. Differential responsiveness within slowly responding mouse strains suggested that parasite-dependent effects were also important. The primary antibody response to T. muris excretory/secretory (E/S) antigen, predominantly an IgG response, was also shown to be controlled by background and H-2-linked genes. In general, mouse strains less resistant to infection developed higher levels of IgG than- more resistant strains of mice. However strains of mice possessing the H-2q haplotype, irrespective of their genetic background, rapidly developed higher levels of IgG1 antibodies than strains of other haplotypes, H-2q haplotype mice tending to be more resistant to infection. Recognition of two high molecular weight (MW) E/S antigens by IgG as revealed by immunoprecipitation was also found to be almost exclusively H-2q restricted. This restriction may be partly quantitative but as such would operate in vivo due to the restriction on the ability to produce high levels of specific IgG. Both H-2q restricted phenomena may be part of, but not absolute requirements for, protective immunity. Parasite-induced effects on host immunity were also studied. Later larval and adult stages of T. muris were shown to be immunosuppressive, immunosuppression being long lasting and preventing the expulsion of subsequent infections. Vaccination with E/S antigen was shown to protect strains of mice which are slow to expel worms (poor-responder) or totally unable to expel worms (non-responder) from a primary infection with T. muris. However protection was slow to be expressed. Antigen recognition profiles of vaccinated strains of mice differed from their primary infection recognition profiles and included the recognition of the two high MW antigens shown to be H-2q restricted in a primary infection. Thus altering the mode or route of E/S antigen presentation may lead to shifts in responsiveness of H-2 genotypes to specific determinants and/or boost specific antibody levels sufficiently to reveal recognition of these antigens. Prior experience of a patent primary infection prevented vaccination protecting non-responder mice against subsequent infections. This inability was correlated with suppressed IgG1 antibody levels and failure to recognise three high MW antigens including the IL-2q restricted antigens. Using a panel of monoclonal antibodies raised against E/S antigen it was shown that E/S antigens, apparently including both immunogenic and immunosuppressive molecules, were localised to granules within the stichocyte cytoplasm of the adult T. muris stichosome.

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Otto, Sarah. "The role of circadian rhythm in the immune response to Trichuris muris." Thesis, University of Manchester, 2013. https://www.research.manchester.ac.uk/portal/en/theses/the-role-of-circadian-rhythm-in-the-immune-response-to-trichuris-muris(cc0b22e0-4fd6-4bf3-8741-f773b9e1783e).html.

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Circadian rhythms have been implicated in severity and outcome of infection and disease. Commonly, LPS and bacterial infection have been used to identify the mechanisms behind the difference in immune responses depending on the time of day of the challenge. In this thesis, the colon dwelling nematode parasite Trichuris muris, which elicits a Th2 immune response in resistant mice, was used to identify if circadian rhythms influence infection outcome 3 weeks post infection. C57BL/6 mice infected with 200 eggs of T. muris at ZT0 (7am, lights on) expelled the parasite more efficiently than mice infected at ZT12 (7pm, lights off), which expelled with a delay of several days compared to ZT0 infected mice. Analysis of cell infiltration into the colon during the first days of infection suggested that there was no visible difference in the local immune response. There also were no differences in macrophage and dendritic cell numbers in colon tissue of naïve mice at ZT0 or ZT12. Further experiments examined immunomodulation of the immune response to T. muris by pushing the immune response towards a Th1, by low dose infection, or a Th2 response, by vaccination with excretory/secretory antigen. In both cases any circadian influence was overwritten. Mice infected at ZT0 or ZT12 with only 40 eggs of T. muris were equally susceptible to infection and mice infected at ZT3 10 days after vaccination at ZT0 or ZT12 were equally resistant to infection. Mice food restricted to mid-light phase and infected at ZT0 were not significantly delayed in their worm expulsion or polarised more towards a Th1 immune response compared to ZT0 infected mice fed during the dark phase. Therefore it is unlikely that feeding behaviour during the first days of infection is able to polarise towards a Th1 response and lead to delayed worm expulsion. Transgenic mice were used to dissect the mechanism underlying the delay in worm expulsion in ZT12 infected mice. mPer2::luc mice were used to confirm rhythmic Per2 expression in colon tissue and dendritic cells. Infection of mPer2::luc mice at ZT0 or ZT12 with T. muris showed similar worm expulsion, antibody and cytokine production when infected at ZT0 or ZT12. Bmal1floxLysMcre mice, which lack rhythmic clock gene expression in macrophages and granulocytes, produced a stronger Th2 antibody response in a primary infection at ZT3 than wild-type littermate controls. Newly generated mPer2::lucBmal1floxCD11ccre mice showed the no difference in worm burden and parasite specific antibody production between ZT0 and ZT12 infected mice. Only IL-10 and IL-6 levels were significantly lower in ZT12 infected mPer2::LucBmal1floxCD11ccre mice compared to ZT12 infected wild-type littermates. Confirmation of removal of exon 8 of the Bmal1 gene was not achieved; therefore it is not clear if circadian rhythm in dendritic cells has any impact on the immune response to T. muris or if the mPer2::LucBmal1floxCD11ccre mice and littermate controls both contain circadian rhythm in dendritic cells and therefore cannot be used to identify the role of the dendritic cell clock in the time of day differences in infection outcome. This thesis shows that time of day of the infection impacts on the outcome of infection with Trichuris muris.

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Robert, Karine. "Contribution à l'étude des mécanismes cellulaires et moléculaires induits par l'hyperhomocysteinemie." Paris 7, 2004. http://www.theses.fr/2004PA077154.

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Bahdoudi, Seyma. "Etude des mécanismes cellulaires et moléculaires impliqués dans les effets neuroprotecteurs du gliopeptide OctaDecaNeuropeptide (ODN) dans un model murin de la Maladie de Parkinson." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR138/document.

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La maladie de Parkinson (MP) est un trouble neurodégénératif caractérisé par une perte progressive de neurones dopaminergiques (DA) de la substance noire pars compacta (SNpc). Différents mécanismes sont associés à la neuropathogénèse de la MP et en particulier le dysfonctionnement de la chaîne respiratoire mitochondriale, le stress oxydatif, l’apoptose et les processus neuro-inflammatoires. L'octadécaneuropeptide (ODN) est un peptide dérivé du diazepam-binding inhibitor (DBI) exprimé par les cellules astrogliales, qui exerce une action neuroprotectrice dans un modèle cellulaire in vitro de la MP. A ce jour, aucune étude in vivo n’a été réalisée, afin de déterminer si les données obtenues sur les modèles cellulaires in vitro peuvent être transposées in vivo. Le projet de cette thèse consiste ainsi à mettre en évidence l’action protectrice de l’ODN sur la survie des neurones DA de la SNpc dans un modèle murin de la MP et à rechercher les conséquences de l’invalidation du gène du précurseur de l’ODN (DBI) sur la vulnérabilité des neurones DA. Les résultats obtenus montrent qu’une seule injection intra-cérébroventriculaire d’une faible quantité d’ODN (10 ng), 1 h après la dernière administration systémique de 1-méthyl-4-phényl-1,2,3,6-tétrahydropyridine (MPTP) prévient significativement la perte des neurones DA dans la substance noire et la dégénérescence de leurs prolongements nerveux vers le striatum comme mesuré par des marquages et des mesures d’expression de la tyrosine hydroxylase. Cet effet neuroprotecteur de l’ODN est accompagné par une réduction du nombre d’astrocytes réactifs, une forte inhibition de l'expression de gènes pro-inflammatoires tels que les interleukines (IL) IL-1β et IL-6, et tumor necrosis factor-α. De plus, l'ODN bloque l'inhibition du gène anti-apoptotique Bcl-2 et la stimulation des gènes pro-apoptotiques Bax et caspase-3, induite par le MPTP dans la SNpc et le striatum. L'ODN réduit également l’accumulation d'espèces réactives de l'oxygène (ROS) et de produits d'oxydation lipidique dans les neurones DA. Par ailleurs, les souris knock-out DBI (DBI-/-) sont plus vulnérables que les animaux sauvages (DBI+/+) vis-à-vis de la neurotoxicité du MPTP. L’absence de production d’ODN endogène, chez les souris DBI-/- parkinsoniennes, augmente les dommages cellulaires induits par le MPTP, la réactivité gliale, les taux de ROS, l’expression de cytokines pro-inflammatoires et l'activité de la caspase-3 dans la région nigro-striée. L’ensemble de ces résultats montre que le gliopeptide ODN exerce un puissant effet neuroprotecteur contre la dégénérescence des neurones DA de la SNpc induite par le MPTP, chez la souris. Cette action protectrice met en jeu des mécanismes impliquant l’inhibition des processus neuro-inflammatoires, oxydatifs et apoptotiques. D’autre part, la déficience en ODN potentialise les effets délétères du MPTP, suggérant que ce peptide joue un rôle clé lors de la réponse à un stress cellulaire
Parkinson's disease (PD) is a neurodegenerative disorder characterized by a progressive loss of loss of dopaminergic (DA) neurons within the substantia nigra pars compacta (SNpc). Different mechanisms are associated with the neuropathogenesis of PD including dysfunction of the mitochondrial respiratory chain, oxidative stress, apoptosis and neuroinflammatory processes. Octadecaneuropeptide (ODN) is a diazepam-binding inhibitor (DBI)-derived peptide, expressed by astrocytes, which protects neurons against oxidative cell damages and apoptosis in an in vitro model of PD. Nevertheless, its protective action in vivo has never been investigated. Therefore, the aim of the project of this thesis was to investigate whether intracerebroventricular (i.c.v) injection of ODN could prevent DA neuron degeneration in a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced mouse model of PD, and to explore the vulnerability of ODN precursor knockout (DBI KO) mice to MPTP-induced neurotoxicity. The results show that a single i.c.v injection of 10 ng/μl ODN, 1 h after the last systemic administration of MPTP, prevents the reduction of the number of tyrosine hydroxylase (TH)-positive cell bodies and fibers in the SNpc and striatum, respectively. Immunofluorescence imaging, Western blot analysis and Q-PCR studies revealed that ODN totally abolished MPTP-induced decrease of TH positive cells, mRNA expression and protein levels. This neuroprotective effect of ODN is accompanied by a reduction in the number of reactive astrocytes, an inhibition of the expression of pro-inflammatory genes such as interleukins (IL) IL-1β and IL-6, and a decrease of tumor necrosis factor -α. In addition, ODN blocks the inhibition of the anti-apoptotic Bcl-2 gene and the stimulation of Bax and caspase-3 expression induced by MPTP in the SNpc and striatum. ODN also reduces the accumulation of reactive oxygen species (ROS) and lipid oxidation products in DA neurons. Furthermore, DBI-/- mice exhibited more vulnerability to MPTP than wild-type animals (DBI+/+). Thus, ODN KO mice are more sensitive to MPTP-induced inflammatory and oxidative brain damages, suggesting that the endogenous OD may also be neuroprotective. These results indicate that, based on its anti-oxidative, anti-inflammatory and anti-apoptotic effect, the gliopeptide ODN could lead to the development of effective therapeutic agents for the treatment of cerebral injuries involving oxidative neurodegeneration

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46

Nicolas, Sarah. "Mise en évidence du potentiel thérapeutique de l’adiponectine et de son rôle dans les effets antidépresseurs de l’environnement enrichi." Thesis, Université Côte d'Azur (ComUE), 2018. http://www.theses.fr/2018AZUR4019/document.

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La dépression est une pathologie multifactorielle induisant des troubles psychiques et physiques. De nouvelles thérapies visant à enrichir l’environnement des patients par des activités physiques, sociales et cognitives aident à la rémission en complément des traitements pharmacologiques. Cependant les bases moléculaires sous-jacentes aux bénéfices observés dans ces thérapies sont méconnues. C’est dans ce contexte que nous avons étudié les effets de ces thérapies via la mise en place d’un modèle murin d’environnement enrichi (EE). L’objectif de ma thèse a été d’évaluer les effets antidépresseurs de l’EE sur un modèle murin de dépression et d’identifier une nouvelle cible thérapeutique. J’ai montré que l’administration chronique de corticostérone induit un état dépressif et une neuroinflammation qui peuvent être réversés par l’EE. De plus, mes travaux ont mis en évidence, l'adiponectine (ApN), comme étant un acteur clef des effets de l'EE. J’ai montré que l’EE via l’ApN était capable de limiter la neuroinflammation. Par ailleurs, la caractérisation de souris n’exprimant pas l’ApN a montré que ces souris étaient insensibles en partie aux effets de l’EE. Par la suite, je me suis intéressée à la voie de signalisation de l’ApN impliquée dans ses effets anti-inflammatoires, j’ai montré que l’ApN inhibe l’activation de la microglie en se liant à son récepteur AdipoR1. Enfin, j’ai testé l’effet de l’AdipoRon, un agoniste des récepteurs de l’adiponectine, sur des souris traitées par la corticostérone. J’ai montré que l’AdipoRon réduisait l’état « dépressif » de ces souris. Mon travaille suggère que les effets antidépresseurs de l’AdipoRon sont dus à sa pléiotropie car il agit simultanément sur différents systèmes altérés dans la dépression dont la neurogenèse hippocampique, la neurotransmission sérotoninergique et la neuroinflammation. Pour conclure ce travail met en avant les effets bénéfiques de l’EE sur la dépression et la neuroinflammation. De plus, ils identifient l’ApN et sa voie de signalisation comme de nouvelles cibles prometteuses dans le traitement de la dépression
Major depression is a complex disorder characterized by behavioral and cognitive impairments triggered by various factors including genetic predispositions, stress and environment. The pathophysiology of depression is poorly understood. Numerous evidence suggests that neuroinflammation is associated with depression. Alternative therapeutic strategies are needed and "positive" life experiences could be an efficient way to help the remission of the disorder. To study the potential antidepressant effects of such “positive” living conditions, we used the enriched environment (EE) paradigm on mice. The aim of our work was to fully characterize the antidepressant and anti-inflammatory effects of EE in a well-characterized murine model of depression-like behavior induced by long-term administration of corticosterone. We showed that EE efficiently reverses the anxiety/depression‐like state of mice and reduces neuroinflammation. Moreover, we identified the adipokine Adiponectin as a key player in the beneficial effects of EE. We reported that increased levels of Adiponectin in the brain led to microglia phenotype and activation state regulation, thus reducing global brain inflammation in mice. Indeed, the anti-inflammatory and antidepressants effects of EE are abolished in Adiponectin deficient mice. We demonstrated that anti-inflammatory actions of Adiponectin on microglia is mediated through the Adiponectin Receptor 1. Those results highlight the key role of the adiponergic system in the treatment of psychiatric disorders. Therefore, we tested the effect of AdipoRon, a potent Adiponectin receptors 1 and 2 agonist on corticosterone-treated mice. AdipoRon successfully reversed the corticosterone-induced depression-like state in mice. AdipoRon exerted its pleiotropic actions on various systems including hippocampal neurogenesis, serotonergic neurotransmission and neuroinflammation, which can explain its antidepressant properties. Together, our findings bring insight into the beneficial effects of "positive" life experiences in depression and neuroinflammation, highlight the pivotal role of Adiponectin pathway and emphasizes that AdipoRon or other Adiponectin receptor agonist may constitute a promising novel antidepressant

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Thépaut, Marion. "Immunomodulation induite par la pré-sensibilisation per os à Norovirus dans un modèle murin de pneumonie aiguë à Pseudomonas aeruginosa." Thesis, Lille 2, 2015. http://www.theses.fr/2015LIL2S033/document.

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Le norovirus murin (MNV) est un agent pathogène de la souris récemment découvert et représente le contaminant le plus courant dans les animaleries de Recherche. Néanmoins, les effets de l'infection au MNV sur la recherche biomédicale ne sont pas encore clairs. Nous avons testé l'hypothèse que l'infection au MNV pourrait modifier la réponse immunitaire chez les souris atteintes d'une infection pulmonaire aiguë. Nous rapportons ici que la co-infection avec MNV augmente la survie des souris ayant une infection pulmonaire aiguë à Pseudomonas aeruginosa et diminue la production in vivo et in vitro de cytokines pro-inflammatoires. Nos résultats suggèrent que l'infection au MNV peut profondément modifier les paramètres étudiés dans les modèles classiques d'infection et mener à de fausses conclusions dans ces modèles expérimentaux
The murine norovirus (MNV) is a recently discovered mouse pathogen, this virus represents the most common contaminant in laboratory mouse colonies. Nevertheless, the effects of MNV infection on biomedical research are still unclear. We tested the hypothesis that MNV infection could alter immune response in mice with acute lung infection. Here we report that co-infection with MNV increases survival of mice with Pseudomonas aeruginosa acute lung injury and decreases in vivo and in vitro production of pro-inflammatory cytokines. Our results suggest that MNV infection can deeply modify the parameters studied in conventional models of in-fection and lead to false conclusions in experimental models

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Karnath, Carolin. "Etablierung eines Keimträgermodells zur Prüfung der viruziden Wirksamkeit von Desinfektionsmitteln." Doctoral thesis, Universitätsbibliothek Leipzig, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-69023.

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Auf dem Gebiet der Veterinärmedizin wird in Deutschland die Desinfektionsmittelprüfung nach den Richtlinien der Deutschen Veterinärmedizinischen Gesellschaft e.V. (DVG) durchgeführt. Diese Richtlinien realisieren derzeit eine Viruzidieprüfung nur für den Bereich Tierhaltung. Daher wurde in dieser Arbeit eine praxisnahe Methodik zur Prüfung der viruziden Wirksamkeit von Desinfektionsmitteln für den Bereich der Lebensmittelproduktion und der tierärztlichen Praxis entwickelt. Neben dem Einsatz von zwei relevanten Prüfviren, erfolgte die Prüfung der viruziden Wirksamkeit anhand fünf verschiedener chemischer Grundsubstanzen. Um praxisähnliche Bedingungen zu simulieren, wurden unterschiedliche Belastungssubstanzen und Prüftemperaturen zur Testung herangezogen. Die gewonnenen Erkenntnisse können somit auf dem Gebiet der Viruzidieprüfung in zukünftige Neufassungen der DVG-Richtlinie berücksichtigt werden.

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49

Pequignot, Amélie. "Modulation par des extraits de Gui fermentés, de sécrétions d'IL-1b et de TNF-a après stimulation in vitro de macrophages murins." Thesis, Montpellier 2, 2010. http://www.theses.fr/2020MON20109/document.

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Dans cette étude, l'aptitude de trois extraits de Gui fermentés (VAF) issus de trois arbres hôtes, à induire ou moduler la sécrétion de cytokines, telles que l'IL-1β, l'IL-6 et le TNF-α, a été explorée à l'aide de deux modèles de macrophages murins. Des traitements prolongés par des concentrations cytotoxiques, mais non sub-cytotoxiques, de VAFs induisent la sécrétion d'IL-1β. Dans ces conditions, les concentrations sub-cytotoxiques de VAFs amplifient les sécrétions d'IL-1β induite après stimulations par le LPS puis l'ATP, ou par l'imiquimod. Par ailleurs, appliqués brièvement et à concentrations sub-cytotoxiques, les VAFs accélèrent la sécrétion d'IL-1β induite après stimulations par le LPS puis l'ATP
In this study, the ability of fermented extracts from mistletoe grown on three host trees to induce or modulate the secretion of pro-inflammatory cytokines, like IL-1β, IL-6 and TNF-α has been explored. Applied for long times, cytotoxic, but not sub-cytotoxic concentrations of fermented mistletoe extracts induce the secretion of IL-1β. In these conditions sub-cytotoxic concentrations increase the IL-1β secretions induced either by LPS and ATP, or by imiquimod. When applied briefy at sub-cytotoxic concentrations, fermented mistletoe extracts can accelerate the secretion of IL-1β induced by LPS and ATP

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Nabbouh, Ali. "Effet de l’Imiquimod et de composés dérivés EAPB0203 et EAPB0503 sur des modèles de leucémies et de lymphomes." Thesis, Montpellier, 2016. http://www.theses.fr/2016MONT3519/document.

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La leucémie myéloïde aiguë (LMA) est une maladie clonale hétérogène caractérisée par une prolifération immature des cellules myéloïdes et une défaillance de la moelle osseuse. Malgré les avancées rapides dans le domaine de la LMA, notamment concernant de nouvelles cibles thérapeutiques et une meilleure compréhension des mécanismes biologiques, le traitement clinique de la LMA reste inchangé et dépend du caryotype des patients. Lors des trois dernières décennies, la plupart des patients ont fini par récidiver et décéder de la maladie ; il n’y a encore aucun schéma thérapeutique standard qui améliore le pronostic et le traitement de la LMA.Les imidazoquinoxalines sont des dérivés de l’imiquimod qui présentent un effet immunomodulateur indirect et une activité anti-tumorale directe contre le mélanome et le lymphome à cellules T, provoquant l’inhibition de la croissance cellulaire et l’induction de l’apoptose par la voie dépendante des caspases . Nous avons étudié les effets des dérivés de la série imidazoquinoxaline, EAPB0203 et EAPB0503, sur des lignées de cellules humaines LMA. Nous avons montré que EAPB0503 inhibe la croissance de la lignée cellulaire LMA qui présente la mutation NPM-1 de manière dose et temps dépendants. Par rapport au dérivé EAPB0203 précédemment synthétisé, EAPB0503 a une activité inhibitrice plus forte sur les cellules OCI-AML3 ainsi que sur des cellules provenant de patients LMA. Nous avons démontré que EAPB0503 induit une dégradation médiée par les protéasomes deNPM-1 muté ainsi qu’un rétablissement de la localisation nucléolaire de NPM-1 sauvage conduisant à une inhibition de la prolifération des cellules OCI-AML3.EAPB0503 induit une apoptose massive comme démontré par l’analyse du cycle cellulaire avec une accumulation de cellules traitées en phase preG0. L’apoptose a été confirmée par la réponse positive au test de l’annexine V, le clivage de PARP et la dissipation du potentiel membranaire mitochondrial dans les cellules OCI-AML3 traitées.En outre, EAPB0503 a augmenté les niveaux d’expression et de phosphorylation de p53.Ces résultats, concernant l’arrêt de la croissance cellulaire et l’apoptose, sélectivement dans les cellules LMA présentant la mutation NPM-1, renforcent l’idée d’un ciblage de l’oncoprotéine NPM-1 muté pour éliminer les cellules leucémiques et justifient une évaluation préclinique plus large puis une évaluation clinique pour ce candidat médicament prometteur.En conclusion, nos études mettent en évidence l'utilisation d’EAPB0503 comme un candidat médicament prometteur qui présente une activité anti-tumorale encourageante et qui devrait faire l’objet d’études précliniques dans le cadre d’une thérapie ciblée contre la LMA
Acute myeloid leukemia (AML) is a heterogeneous clonal disorder characterized by immature myeloid cell proliferation and bone marrow failure. Although the remarkable improvements in the field and regarding new drug targets and better understanding of the biology, the clinical treatment of AML remains unchanged and depending on karyotype of patients. For the last thirty years with the majority of patients, in the end, relapsing and dying of the disease, there is no standard regimen that improves prognosis and treat AML yet.Imidazoquinoxalines are imiquimod derivatives with indirect immunomodulatory effect and direct antitumor activity on melanoma and T-cell lymphoma, attributed to growth inhibition and induction of apoptosis through caspase-dependent pathway. We examined the effects of imidazoquinoxaline derivatives, EAPB0203 and EAPB0503, on human AML cells. We found that EAPB0503 inhibit cell growth of AML cell line that harbors the NPM-1 mutation in a time- and dose-dependent way. Compared to the previously synthesized EAPB0203, EAPB0503 has a more pronounced inhibitory activity on OCI-AML3 cells and cells derived from AML patients as well. We demonstrated that the EAPB0503 induces proteasome-mediated degradation of mutant NPM-1, and restoration of the nucleolar localization of the NPM-1wt leading to an inhibition of the proliferation of OCI-AML3 cells.EAPB0503 induced massive apoptosis as demonstrated with the cell cycle analysis by the accumulation of treated cells in the preG0 region. Apoptosis has been confirmed by Annexin V positivity, PARP cleavage, and dissipation of mitochondrial membrane potential in treated OCI-AML3 cells.Furthermore, EAPB0503 increased the expression and phosphorylation levels of p53.These results in growth inhibition and apoptosis, selectively in AML cells that harbor the NPM-1 mutation reinforce the idea targeting NPM-1m oncoprotein to eradicate leukemic cells and warrant a broader preclinical then clinical evaluation of this promising drug.In conclusion, our studies highlight the use of EAPB0503 as a promising anti-tumor activity to be investigated preclinically in AML targeted therapy

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Dissertations / Theses on the topic 'Murids'

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