250 resultados para Eae


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This study characterized 76 atypical enteropathogenic Escherichia coli (aEPEC) strains, previously classified by the eae(+) EAF-negative stx(-) genotype, isolated from children with diarrhea in Brazil. Presence of bfpA and bfpA/perA was detected in 2 and 6 strains, respectively. The expression of bundle-forming pilus (BFP), however, was observed by immunofluorescence in 1 bfpA and 3 bfpA/perA strains, classifying them as typical EPEC (tEPEC). The remaining 72 aEPEC strains were characterized by serotyping, intimin typing, adherence patterns to HEp-2 cells, capacity to induce actin aggregation (fluorescent actin staining test), and antimicrobial resistance. Our results show that aEPEC comprise a very heterogeneous group that does not present any prevalence or association regarding the studied characteristics. It also suggest that tEPEC and aEPEC must not be classified only by the reactivity with the EAF probe, and that the search of other markers present in pEAF, as well as the BFP expression, must be considered for this matter. (C) 2009 Elsevier Inc. All rights reserved.

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Multiple sclerosis (MS) is an autoimmune disease characterized by inflammatory immune response directed against myelin antigens of the central nervous system. In its murine model, EAE, Th17 cells play an important role in disease pathogenesis. These cells can induce blood-brain barrier disruption and CNS immune cells activation, due to the capacity to secrete high levels of IL-17 and IL-22 in an IL-6 + TGF-beta dependent manner. Thus, using the oral tolerance model, by which 200 mu g of MOG 35-55 is given orally to C57BL/6 mice prior to immunization, we showed that the percentage of Th17 cells as well as IL-17 secretion is reduced both in the periphery and also in the CNS of orally tolerated animals. Altogether, our data corroborates with the pathogenic role of IL-17 and IFN-gamma in EAE, as its reduction after oral tolerance, leads to an overall reduction of pro-inflammatory cytokines, such as IL-1 alpha, IL-6, IL-9, IL-12p70 and the chemokines MIP-1 beta, RANTES, Eotaxin and KC in the CNS. It is noteworthy that this was associated to an increase in IL-10 levels. Thus, our data clearly show that disease suppression after oral tolerance induction, correlates with reduction in target organ inflammation, that may be caused by a reduced Th1/Th17 response. Crown Copyright (c) 2010 Published by Elsevier B.V. All rights reserved.

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La Esclerosis Múltiple es una de las enfermedades autoinmunes del Sistema Nervioso Central más frecuentes en adultos jóvenes. Un modelo experimental de la misma es la Encefalomielitis Autoinmune Experimental (EAE). Numerosos trabajos demuestran que en EAE, los clones patogénicos capaces de transferir la enfermedad son células T cooperadoras tipo 1 (Th1), mientras que las células T cooperadoras tipo 2 (Th2) actuarían como clones protectivos. Debido a las funciones opuestas de estas dos poblaciones existe la posibilidad de que la desregulación inmune asociada a Esclerosis Múltiple y su modelo experimental EAE se relacione a un desbalance Th1-Th2. La célula presentadora de antígeno (CPA), la dosis de antígeno, su ruta de entrada, el tipo de interleuquina presente en el medio, las moléculas co-estimulatorias de la CPA, etc., son fundamentales para la inducción de poblaciones Th1 ó Th2. Las estrategias terapéuticas actuales intentan suprimir la enfermedad administrando el autoantígeno por distintas vías, como por ejemplo la vía oral, intragástrica, endovenosa, etc. La inducción de tolerancia utilizando la vía intraperitoneal (ip) no ha sido muy explorada. Recientemente hemos iniciado una nueva línea de trabajo en la cual se suprimió la EAE inyectando i.p. antígenos de mielina en días previos a la inmunización. El objetivo de este proyecto será estudiar la vía i.p. y las CPA peritoneales en la inducción de supresión de la EAE. Se analizará: 1) El mecanismo inmunológico por el cual se induce supresión al inyectar antígenos de mielina por la vía i.p., estudiando si en los animales suprimidos se genera un estado de anergia al autoantígeno y/o células capaces de regular negativamente la respuesta autoinmune. 2) Si las CPA peritoneales pulsadas in vivo con antígenos de mielina al ser transferidas a animales receptores singénicos en días previos a la inmunización con mielina bovina son capaces de inducir supresión de la respuesta autoinmune en los animales receptores. 3) El fenotipo de las CPA peritoneales ya que se sabe que CPA que expresen determinadas moléculas de superficie tales como antígenos del Complejo Mayor de Histocompatibilidad, moléculas de adhesión, moléculas coestimulatorias, etc., participan activamente en el destino final de la respuesta inducida.

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Via a transcription factor, Foxp3, immunoregulatory CD4(+)CD25(+) T cells (T reg cells) play an important role in suppressing the function of other T cells. Adoptively transferring high numbers of T reg cells can reduce the intensity of the immune response, thereby providing an attractive prospect for inducing tolerance. Extending our previous findings, we describe an in vivo approach for inducing rapid expansion of T reg cells by injecting mice with interleukin (IL)-2 mixed with a particular IL-2 monoclonal antibody (mAb). Injection of these IL-2-IL-2 mAb complexes for a short period of 3 d induces a marked (>10-fold) increase in T reg cell numbers in many organs, including the liver and gut as well as the spleen and lymph nodes, and a modest increase in the thymus. The expanded T reg cells survive for 1-2 wk and are highly activated and display superior suppressive function. Pretreating with the IL-2-IL-2 mAb complexes renders the mice resistant to induction of experimental autoimmune encephalomyelitis; combined with rapamycin, the complexes can also be used to treat ongoing disease. In addition, pretreating mice with the complexes induces tolerance to fully major histocompatibility complex-incompatible pancreatic islets in the absence of immunosuppression. Tolerance is robust and the majority of grafts are accepted indefinitely. The approach described for T reg cell expansion has clinical potential for treating autoimmune disease and promoting organ transplantation.

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The role of regulatory T cell populations within the CNS in the regulation of CNS-autoimmunity is controversial. We show that during recovery from relapsing remitting experimental autoimmune encephalomyelitis, regulatory T cells accumulate within the CNS that express high levels of CD62L. These CD62L(high) Treg cells express increased amounts of CTLA-4, ICOS and TGF-β and are more potent than CD62L(low) Treg cells in suppressing proliferation and inducing apoptosis in effector T cells. CD62L(high) Treg cells thus represent a population of Treg cells that display superior immunosuppressive properties and accumulate in the CNS during recovery from CNS-autoimmunity.

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Estudiar los intereses profesionales de una muestra de población con discapacidad física y sensorial. Analizar la percepción que tienen de sí mismas esas personas. Contribuir a dotar de recursos a los profesionales de la orientación y evaluación profesional.. La componen 31 sujetos que cursan estudios en un centro de recuperación de minusválidos físicos. Cerca del 45 por ciento presentan discapacidades sensoriales. Para la realización del PASS se eligen 4 sujetos, con edades comprendidas entre los 24 y 26 años, dos con lesión medular y 2 con hipoacusia bilateral.. Se lleva a cabo una revisión teórica sobre distintos aspectos de la evaluación y de la orientación profesional, describiendo las implicaciones de una nueva concepción. A partir de los objetivos, plantea una serie de hipótesis: ¿cuál es el grado de madurez profesional de los sujetos con discapacidad física y sensorial?, ¿qué relación existe entre sus preferencias y los estudios que están cursando?, ¿qué nivel de adecuación existe entre sus expectativas y su capacidad real?, ¿cuál es la percepción que tienen de sí mismos?, ¿en qué medida el método 'exploratorio' constituye alternativa válida para la evaluación y orientación profesional de estos sujetos?, ¿la aplicación del PASS aumentará el grado de conocimiento en ciertas áreas?.. Se aplican tres pruebas: el inventario de intereses profesionales (RMI), la escala de autoestimación (EAE) y el instrumento de evaluación del potencial profesional (PASS).. Se utilizan estadísticos descriptivos (medias y desviaciones típicas) y análisis de correlaciones. Se efectúan análisis cuantitativos mediante la prueba de rangos.. Los sujetos que siguieron el curso del PASS han obtenido mejoras relacionadas por una parte con el conocimiento y definición de los propios intereses profesionales, y por otra sobre la consideración de sí mismos. Se observa un aumento del grado de conocimiento de sí mismos y de las posibilidades a su alcance. Los sujetos informan sobre una toma de decisiones y acciones concretas orientadas a la búsqueda de empleo.. El sistema PASS ofrece una metodología sistemática de recogida de información que con las debidas modificaciones puede ser utilizado tanto por los profesionales como por estos sujetos. Los datos obtenidos parecen sugerir que existe la necesidad de aumentar los conocimientos de las personas con discapacidad física y sensorial, sobre las profesiones y salidas laborales existentes. También es preciso que aumente su conocimiento sobre las profesiones más adecuadas a sus capacidades. Se advierte que en próximas investigaciones será necesario atender a aspectos puramente prácticos pero de gran importancia (horarios, intervalos entre sesiones, estructuración del curso, etc.)..

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Existe una versi??n en espa??ol, con el t??tulo "Comunidades de Aprendizaje en la CAPV. Una respuesta educativa en la sociedad de la informaci??n para todos y todas"

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Ruminants are regarded as a primary reservoir for Escherichia coli O157:H7, an important human pathogen. Intimin, encoded by the Locus of Enterocyte Effacement by E. coli O157:H7 organisms, has been cited as one bacterial mechanism of colonisation of the gastrointestinal tract. To confirm this and to test whether a non-toxigenic E. coli O157:H7 strain would colonise and persist in a sheep model, E. coli O157:H7 strain NCTC12900, that lacks Shiga toxin (stx) genes, was evaluated for use in a sheep model of persistence. Following oral inoculation of six-week-old sheep, persistent excretion of NCTC12900 was observed for up to 48 days. E. coli O157-associated attaching-effacing (AE) lesions were detected in the caecum and rectum of one six-week-old lamb, one day after inoculation. This is the first recorded observation of AE lesions in orally inoculated weaned sheep. Also, mean faecal excretion scores of NCTC12900 and an isogenic intimin (eae)-deficient mutant were determined from twenty-four six-week-old orally inoculated sheep. The eae mutant was cleared within 20 days and had lower mean excretion scores at all time points after day one post inoculation compared with the parental strain that was still being excreted at 48 days. Tissues were collected post mortem from animals selected at random from the study groups over the time course of the experiment. The eae mutant was detected in only 1/43 samples but the parental strain was recovered from 64/140 samples primarily from the large bowel although rumen, duodenum, jejunum, and ileum were culture positive especially from animals that were still excreting at and beyond 27 days after inoculation.

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Mastitis has been recognized for some time as the most costly disease in dairy herds. From March 1997 to August 1998. 2144 samples of bovine mastitic milk were collected, from which 182 Escherichia coli isolates were made, and from which 14 1 isolates had the somatic anti-en (serogroup) determined. Twelve different serogroups were isolated from mastitic milk, and among them were 026, 055, 0111 and 0 119, all of them classic enteropathogenic E. (oh (EPEC) serogroups. These represented 40.0% of the isolates. The 20 of 57 isolates tested had plasmids and in dot blot hybridization, nine isolates were positive for an EaeA probe and an EPEC adherence factor (EAF) probe while two isolates were negative for EaeA probe but positive for the EAF probe, the nine isolates were characterized as attaching and effacing (A/E) E, coli (AEEC) isolates. (C) 2002 Elsevier B.V. B.V. All rights reserved.

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Experimental autoimmune encephalomyelitis (EAE) is an artificially induced demyelination of the central nervous system (CNS) that resembles multiple sclerosis in its clinical, histopathological, and immunological features. Activated Th1 and Th17 cells are thought to be the main immunological players during EAE development. This study was designed to evaluate peripheral and local contribution of IL-17 to acute and chronic EAE stages. C57BL/6 mice were immunized with MOG plus complete Freund's adjuvant followed by pertussis toxin. Mice presented an initial acute phase characterized by accentuated weight loss and high clinical score, followed by a partial recovery when the animals reached normal body weight and smaller clinical scores. Spleen cells stimulated with MOG produced significantly higher levels of IFN-γ during the acute period whereas similar IL-17 levels were produced during both disease stages. CNS-infiltrating cells stimulated with MOG produced similar amounts of IFN-γ but, IL-17 was produced only at the acute phase of EAE. The percentage of Foxp3+ Treg cells, at the spleen and CNS, was elevated during both phases. The degree of inflammation was similar at both disease stages. Partial clinical recovery observed during chronic EAE was associated with no IL-17 production and presence of Foxp3+ Treg cells in the CNS. © 2013 Sofia Fernanda Gonçalves Zorzella-Pezavento et al.