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Early immune response against foot and mouth disease virus
No full textLa infección de ratones con el Virus de la Fiebre Aftosa (VFA) induce una respuesta de anticuerpos neutralizantes en forma timo-independiente (TI), que rápidamente elimina al virus del organismo. Por el contrario, la vacunación con el virus inactivado induce una típica respuesta timo-dependiente (TD). En este trabajo de tesis se demuestra que las células dendríticas (CDs) murinas son susceptibles a la infección con el VFA in vitro. Sin embargo, la replicación viral en ellas es abortiva. En células infectadas, la expresión de las moléculas del complejo mayor de histocompatibilidad de clase II y CD40 decrece, mientras que la expresión de la molécula CD11b aumenta. Junto con estas alteraciones en el fenotipo, las células infectadas presentan modificaciones en su morfología y en su funcionalidad que, en conjunto, son indicativas de la adquisición de un fenotipo macrofágico. Asimismo, las CDs infectadas son incapaces de estimular la proliferación de linfocitos T in vitro y de inducir una respuesta de anticuerpos secundaria in vivo. La infección de las CDs induce en ellas la secreción de IL-6 y además induce la secreción de interferón-gamma (IFN-γ) y de IL-10 en los co-cultivos CDs y esplenocitos. Estas mismas citoquinas son detectadas en los bazos de ratones infectados con el VFA, pero no en los bazos de ratones vacunados. El pico de la secreción de IFN-γ y de IL- 10 se produce en forma simultánea con la supresión de la proliferación inducida por Concanavalina-A de los linfocitos T obtenidos de los bazos de ratones infectados. A pesar de suprimir las TD durante la infección temprana con el VFA, las CDs infectadas estimulan eficientemente a los linfocitos B del bazo, quienes producen anticuerpos TI contra el virus en forma rápida. La secreción de estos anticuerpos es dependiente de la presencia de las citoquinas IL-6 e IL-10. Por el contrario, los linfocitos B de los ganglios linfáticos son incapaces de responder a la estimulación con las CDs infectadas. Los linfocitos B CD9+ localizados en el bazo son los principales productores de los anticuerpos TI contra el VFA y de la secreción de IL-10. En efecto, la esplenectomía de los 2 ratones produce un cambio en el tipo de respuesta, la cual se vuelve TD. La eliminación funcional de los linfocitos B de la zona marginal inhibe significativamente la secreción de anticuerpos luego de la infección con el VFA, indicando que esta población de linfocitos B cumple un importante papel en la respuesta temprana contra este virus. Contrariamente a lo observado con las CDs infectadas, las CDs que internalizaron al VFA inactivado estimulan linfocitos B con menor eficiencia y no inducen la secreción de IL-10 por los mismos. En conjunto, estos resultados indican que luego de la infección con el VFA, las CDs adquieren un perfil funcional que les permite la eficiente estimulación de los linfocitos B, mientras que la capacidad de estas células para estimular a los linfocitos T se encuentra inhibida. Por lo tanto, durante la respuesta inmune temprana contra el VFA, se produce una supresión selectiva del compartimiento del sistema inmune involucrado en las respuestas TD, mientras que el compartimiento involucrado en la producción de anticuerpos TI protectores es eficientemente estimulado.Foot-and-Mouth Disease Virus (FMDV) is a cytopathic virus that infects mice inducing a thymus-independent (TI) neutralizing antibody response that rapidly clears the virus. In contrast, vaccination with UV-inactivated virus induces a typical thymus-dependent (TD) response. Herein, we show that dendritic cells (DCs) are susceptible to infection with FMDV in vitro, although viral replication is abortive. Infected DCs down-regulate the expression of MHC class II and CD40 molecules and up-regulate expression of CD11b. In addition, infected DCs exhibit morphological and functional changes towards a macrophage-like phenotype. FMDV-infected DCs fail to stimulate T-cell proliferation in vitro and to boost an antibody response in vivo. Moreover, infection of DCs in vitro induces the secretion of gamma-interferon (IFN-γ) and IL-10 in cocultures of DCs and splenocytes. High quantities of these cytokines are also detected in the spleens of FMDV-infected mice, but not in the spleens of vaccinated mice. The peak of secretion of gamma-interferon and IL-10 is concurrent with the suppression of Concanavalin A-mediated proliferation of T cells obtained from the spleens of infected mice. Despite the suppression of TD responses during early infection with FMDV, FMDV-infected DCs efficiently stimulate B lymphocytes from the spleen, which rapidly secrete anti-FMDV TI antibodies. The secretion of these antibodies depends on the presence of IL-6 and IL-10. In contrast, B lymphocytes from lymph-nodes are unable to produce anti-FMDV antibodies upon stimulation with infected DCs. CD9+ B lymphocytes CD9+ in the spleen are the main producers of TI anti-FMDV antibodies and of the secretion of IL-10. Indeed, splenectomy switches the mode of activation of the anti-FMDV immune response from a TI to a TD way. Functional depletion of marginal zone B lymphocytes significantly inhibits the secretion of anti-FMDV antibodies after infection, indicating that this subset of B lymphocytes plays a critical role in the early immune response against this virus. In contrast, DCs loaded with 4 inactivated FMDV are poor stimulators of B lympocytes. In addition, they do not induce the secretion of IL-10 upon co-culture with splenocytes. Altogether, these results indicate that while early after infection with FMDV DCs become potent stimulators of B lymphocytes, their ability to stimulate T lymphocytes is impaired. Thus, during the early immune response against FMDV, a selective suppression of the immune compartment involved in TD responses is established. In contrast, the immune compartment in charge of the production of TI protective antibodies is efficiently stimulated.Fil: Ostrowski, Matías. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentina
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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