Search

Your search keyword '"Ewbank J"' showing total 116 results
Start Over Author "Ewbank J"
116 results on '"Ewbank J"'

1. Mycobacterium tuberculosis induced transcription in macrophages : the role of TPL2/ERK signalling in the negative regulation of type I interferon production and implications for control of tuberculosis

Author

Ewbank, J. B.

Subjects
616
Abstract

Mycobacterium tuberculosis is an important global cause of mortality and morbidity. The major host cell of Mycobacterium tuberculosis is the macrophage, and Mycobacterium tuberculosis is able to subvert the macrophage response in order to survive and replicate. The majority of infected individuals mount an immune response capable of controlling Mycobacterium tuberculosis infection. This requires the cytokines IL-12, TNFα, IL-1 and IFNγ, which promote eradication or control of infection. However, other immune factors, including IL-10 and type I IFN, can inhibit this protective response. In this study we have used microarray analysis to study the temporal response of macrophages to Mycobacterium tuberculosis infection, in an unbiased fashion. In response to Mycobacterium tuberculosis infection, macrophages produced cytokines and chemokines, upregulated genes involved with major histocompatability class I antigen presentation, activated both pro- and anti-apoptotic genes and downregulated many genes involved in cell-division and metabolism. We also observed the early induction of genes regulated by the extracellular-regulated kinase (ERK) MAP kinase pathway, and the upregulation of genes known to be induced by type I IFN, leading us to further investigate the role of these pathways in the macrophage response to Mycobacterium tuberculosis. Both pathways were found to regulate the production of protective and detrimental cytokines in macrophages in response to Mycobacterium tuberculosis infection. In addition, microarray analysis found that these pathways controlled the transcription of numerous genes in response to Mycobacterium tuberculosis infection. Finally, type I IFN was found to inhibit the macrophage response to IFNγ, including IFNγ-mediated killing of Mycobacterium tuberculosis in macrophages, a crucial step in the control of Mycobacterium tuberculosis infection in vivo. We have therefore identified important regulatory mechanisms in macrophages, which are likely have an important role during Mycobacterium tuberculosis infection in vivo.

Published
2012

9. Les modèles animaux en recherche biomédicale

Author

Malissen, M., Vallet-Erdtmann, V., Guillou, Florian Jean Louis, Hérault, Y., Ewbank, J., Houdebine, Louis, Cotinot, Corinne, Institut National de la Santé et de la Recherche Médicale (INSERM), Centre National de la Recherche Scientifique (CNRS), Université de la Méditerranée - Aix-Marseille 2, Ministère de l'Enseignement Supérieur et de la Recherche (MESR), Physiologie de la reproduction et des comportements [Nouzilly] (PRC), Institut National de la Recherche Agronomique (INRA)-Institut Français du Cheval et de l'Equitation [Saumur] (IFCE)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Université de Strasbourg (UNISTRA)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Biologie du développement et reproduction (BDR), École nationale vétérinaire - Alfort (ENVA)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS), Institut National de la Recherche Agronomique (INRA)-Institut Français du Cheval et de l'Equitation [Saumur]-Université de Tours-Centre National de la Recherche Scientifique (CNRS), U964, Centre National de la Recherche Scientifique (CNRS)-École nationale vétérinaire d'Alfort (ENVA)-Institut National de la Recherche Agronomique (INRA), Institut National de la Recherche Agronomique (INRA)-Institut Français du Cheval et de l'Equitation [Saumur]-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université de Tours-Institut Français du Cheval et de l'Equitation [Saumur]-Institut National de la Recherche Agronomique (INRA), Biologie du Développement et Reproduction (BDR), Institut National de la Recherche Agronomique (INRA), and ProdInra, Archive Ouverte

Subjects
[SDV.BIO]Life Sciences [q-bio]/Biotechnology, BIOLOGIE, GENETIQUE, RECHERCHE BIOMEDICALE, [SDV.BIO] Life Sciences [q-bio]/Biotechnology
Abstract

Dossier - Modèles de vie; absent

Published
2010

10. A generalized transducing phage ({phi} IF3) for the genomically sequenced Serratia marcescens strain Db11 : a tool for functional genomics of an opportunistic human pathogen

Author

Petty, N.K., Foulds, I.J., Pradel, E., Ewbank, J., Salmond, Gp, Centre d'Immunologie de Marseille - Luminy (CIML), Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Guglietta, Noëlle, and Aix Marseille Université (AMU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)

Subjects
DNA, Bacterial, [SDV.IMM] Life Sciences [q-bio]/Immunology, Transduction, Genetic, Myoviridae, bacteria, Humans, [SDV.IMM]Life Sciences [q-bio]/Immunology, Bacteriophages, Microbiology, Lysogeny, Serratia marcescens, Genome, Bacterial
Abstract

A bacteriophage (phi IF3) capable of mediating generalized transduction in Serratia marcescens strain Db11 has been isolated and characterized. The genome of this Serratia strain has recently been sequenced and is likely to become the reference strain fo

Published
2006

19. CLK-1 controls respiration, behavior and aging in the nematode Caenorhabditis elegans.

Author

Felkai, S., Ewbank, J. J., Lemieux, J., Labbe, J.-C., Brown, G. G., and Hekimi, S.

Subjects
*AGING, *DEVELOPMENTAL biology, *GERONTOLOGY, *CAENORHABDITIS elegans, *CAENORHABDITIS, *MITOCHONDRIA, *ORGANELLES, *PROTOPLASM
Abstract

Mutations in the clk-1 gene of the nematode Caenorhabditis elegans result in an average slowing of a variety of developmental and physiological processes, including the cell cycle, embryogenesis, post-embryonic growth, rhythmic behaviors and aging. In yeast, a CLK-1 homologue is absolutely required for ubiquinone biosynthesis and thus respiration. Here we show that CLK-1 is fully active when fused to green fluorescent protein and is found in the mitochondria of all somatic cells. The activity of mutant mitochondria, however, is only very slightly impaired, as measured in vivo by a dye-uptake assay, and in vitro by the activity of succinate cytochrome c reductase. Overexpression of CLK-1 activity in wild-type worms can increase mitochondrial activity, accelerate behavioral rates during aging and shorten life span, indicating that clk-1 regulates and controls these processes. These observations also provide strong genetic evidence that mitochondria are causally involved in aging. Furthermore, the reduced respiration of the long-lived clk-1 mutants suggests that longevity is promoted by the age-dependent decrease in mitochondrial function that is observed in most species. [ABSTRACT FROM AUTHOR]

Published
1999
Full Text
View/download PDF

20. Molecular electron diffraction from a space-charge limited beam.

Author

Faust, W. L., Ewbank, J. D., Monts, D. L., and Schafer, L.

Subjects
*ELECTRON diffraction, *LASERS, *ELECTRON beams, *SCIENTIFIC apparatus & instruments
Abstract

We are developing an apparatus to employ gas electron diffraction (GED) for the study of transient molecular species generated by a pulsed excimer/dye-laser system, in a new type of excite-and-probe experiment. This paper treats problems which arise in design ora suitable pulsed electron-beam source, to provide relatively high instantaneous current. Standard electron-beam theory is extended to define focal conditions under which sharp patterns may be recorded. We have characterized several components of blur and distortion, particularly those due to electrostatic repulsion between the main beam and the diffracted electrons. The analysis may find use in other work, e.g., with microscopic beams. [ABSTRACT FROM AUTHOR]

Published
1988
Full Text
View/download PDF

25. The homeodomain protein CePHOX2/CEH-17 controls antero-posterior axonal growth in C. elegans.

Author

Pujol, N, Torregrossa, P, Ewbank, J J, and Brunet, J F

Abstract

An essential aspect of a neuron's identity is the pattern of its axonal projections. In C. elegans, axons extend either longitudinally or circumferentially in response to distinct molecular cues, some of which have been identified. It is currently unclear, however, how the differential capacity to respond to these cues is transcriptionally implemented in distinct neuronal subtypes. Here, we characterise a C. elegans paired-like homeobox gene, CePhox2/ceh-17, expressed in five head neurons, ALA and the 4 SIAs, all of which project axons towards the tail along the lateral and sublateral cords. Abrogation of ceh-17 function, while leaving intact many phenotypic traits of these neurons, disrupts their antero-posterior axonal elongation beyond the mid-body region. Conversely, ectopic expression of ceh-17 in the mechanoreceptors, several of which are known to pioneer their tract, leads to exaggerated longitudinal axonal outgrowth. Thus, ceh-17 is a novel gene involved in fasciculation-independent longitudinal axonal navigation.

Published
2000

27. Processor-Controlled Microdensitometry

Author

Ewbank, J. D., Bowers, P., Pinegar, J., and Schafer, L.

Abstract

A new scheme of densitometric data collection is described which comprises a digital filtering technique and process control program. A 6502-based PET 2001/32K microcomputer and an Elscan model 2500 specular microdensitometer are interfaced through the standard 6522 VIA port chip. An Analog Devices ADC80/12 monolithic A/D converter is used to digitize the analog output of the light photometering system. Additionally, control of the optical scanner assembly is provided through processor-driven 4-phase TTL logic circuitry. The technique applies to any analog signal of interest, either for filtering purposes or for recording directly into memory for later waveform or transient analysis. The maximum data gathering rate is 40 kHz, limited by the A/D conversion time of 25 μs.

Published
1981
Full Text
View/download PDF

28. Gas Electron Diffraction Study of the 193-nm Laser-Induced Interconversion between Cis- and Trans-1,2-Dichloroethylene

Author

Monts, D. L., Ewbank, J. D., Siam, K., Faust, W. L., Paul, D. W., and Schäfer, L.

Abstract

Gas electron diffraction (GED) data were recorded of 193-nm irradiated cis- and trans-1,2-dichloroethylene. The interconversion between the cis-and trans-isomers and the formation of chloroacetylene can be inferred from the diffraction intensities. The experiments demonstrate the utility of GED in the study of chemical reactions.

Published
1987
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results