1,721,001 research outputs found

    Induction of nitric oxide synthase is involved in the mechanism of Fas-mediated apoptosis in haemopoietic cells.

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    Induction of nitric oxide synthase (iNOS) and production of the toxic metabolite nitric oxide (NO) is one of the interferon-gamma (IFN-gamma) and tumour necrosis factor-alpha (TNF-alpha) regulated effector mechanisms that can lead to apoptosis of haemopoietic progenitor cells. Fas-receptor (Fas-R) expression can be stimulated by IFN-gamma and TNF-alpha. Transactivation of iNOS, and possibly Fas-R promoters, by interferon regulatory factor-1 expressed in response to IFN-gamma may be a part of the iNOS transduction pathway. We investigated whether the effects of Fas-R triggering in haemopoietic cells were mediated by NO. On Western blotting, we observed that Fas-receptor agonist, monoclonal antibody CH11. enhanced expression of iNOS. As shown by the reverse transcription polymerase chain reaction. CH11 also induced iNOS mRNA expression in purified CD34+ cells. To determine whether NO was involved in Fas-mediated apoptosis we inhibited iNOS-catalysed production of NO using anti-sense (AS) oligodeoxynucleotides (ODN) directed against iNOS mRNA. After culture of haemopoietic cells in the presence of AS-ODN, iNOS expression decreased and was no longer enhanced by Fas. This effect was associated with the prevention of Fas-mediated apoptosis, as determined by a DNA fragmentation and terminal deoxynucleotidyl transferase staining. In colony assays, specific AS-oligonucleotides prevented FAS-mediated inhibition of colony formation by total bone marrow and CD34+ progenitor cells. Our data suggest that the inhibitory effects of Fas, including induction of apoptosis, are mediated by effector mechanisms that may be similar to those described for IFN-gamma and TNF-alpha

    Low-dose interleukin-2 for treating postautologous transplant cytogenetic abnormality recurrency in a case of acute myeloid leukemia with hyperdiploidy.

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    Adoptive immunotherapy and/or immunostimulation may be effective in treating early phases of leukemia relapsing after allogeneic transplant. Donor lymphocyte infusion (DLI) is an established treatment for cytogenetic relapse of chronic myeloid leukemia (CML) after unmanipulated or T-cell–depleted bone marrow transplant (BMT)1; favorable results have also been reported in a few cases of initial posttransplant relapse of acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML).2 A graft-versus-leukemia (GVL) effect as part of a manifest or occult DLI-elicited graft-versus-host disease (GVHD) is thought to be the reason for these favorable results. For patients who had received autologous transplant, attempts to elicit an antineoplastic effect by immunostimulation have been made using in vitro interleukin-2 (IL-2)–activated autologous lymphocytes and/or IL-2 in vivo administration.34 We report on the successful use of subcutaneous (sc) low-dose IL-2 in a patient suffering from AML with recurrence of cytogenetic abnormalities after autografting

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The 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

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    “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

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    We 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
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