1,721,072 research outputs found
A constitutively active SPTBN1-FLT3 fusion in atypical chronic myeloid leukemia is sensitive to tyrosine kinase inhibitors and immunotherapy
Objectives
To determine the consequences and significance of an acquired 46XX,t(2;13;2;21)(p13;q12;q33;q11.2) in atypical chronic myeloid leukemia (aCML).Methods
Translocation breakpoints were identified by fluorescence in situ hybridization and a novel fusion gene identified by rapid amplification of cDNA ends polymerase chain reaction. Functional analysis of the fusion was performed using the Ba/F3 transformation assay and specific inhibition demonstrated using small molecule inhibitors.Results
Fluorescence in situ hybridization indicated that FLT3 at 13q12 was disrupted and 5?-rapid amplification of cDNA ends polymerase chain reaction identified a novel in-frame mRNA fusion between exon 3 of SPTBN1 (spectrin, ?, nonerythrocytic 1) at chromosome 2p16 and exon 13 of FLT3. Expression of SPTBN1-FLT3 transformed Ba/F3 cells to growth factor independence and was accompanied by constitutive phosphorylation of the fusion protein and the downstream substrate extracellular signal-regulated kinase 1/2. The growth of transformed cells was inhibited in a dose-dependent fashion by SU11657, PKC412, and TKI258 (CHIR-258), but not by imatinib. To determine if FLT3 might be involved more widely in BCR-ABL–negative aCML, we analyzed 40 cases and found two were internal tandem duplication–positive, but D835 mutations were not observed. The t(2;13;2;21) patient was initially treated with hydroxyurea and subsequently underwent an unrelated donor bone marrow transplantation. She relapsed cytogenetically at 4 years, but responded to donor lymphocyte infusion, achieving sustained cytogenetic and molecular (nested reverse transcription polymerase chain reaction) remission.Conclusion
Although FLT3 abnormalities are uncommon in aCML, SPTBN1-FLT3 is a novel constitutively active tyrosine kinase that appears to responsive to both targeted signal transduction therapy and immunotherapy
SPTBNI-FLT3 in atypical chronic myeloid leukemia transforms Ba/F3 cells to IL-3 independence and is sensitive to both tyrosine kinase inhibitors and immunotherapy
We have identified a patient who presented with BCR-ABL negative chronic myeloid leukemia (CML) and an acquired 46XX, t(2;13;2;21) (p13;q12;q33;q11.2) in all bone marrow metaphases examined. Fluorescence in situ hybridization (FISH) using probes flanking the FLT3 gene at 13q12 suggested that this gene was disrupted. 5'-RACE PCR using primers to the region of FLT3 encoding the tyrosine kinase domain identified a novel in-frame mRNA fusion between exon 3 of SPTBN1 (spectrin, beta, non-erythrocytic 1 isoform 2, NM 178313) on chromosome 2p16 and exon 13 of FLT3 (NM 004119). Juxtaposition of SPTBN1 and FLT3 was confirmed by two color FISH and amplification of the genomic DNA breakpoint confirmed a fusion between intron 3 of SPTBN1 and intron 12 of FLT3. The SPTBN1-FLT3 fusion gene is predicted to be translated into a 570 amino acid chimeric protein that retains two coiled-coil domains from SPTBN1 and 424 amino acids from FLT3, including the entire tyrosine kinase domain. Since the t(2;13) is readily visible by cytogenetic analysis but has not been reported previously it seems likely that SPTBN1-FLT3 is uncommon. However to test if FLT3 might be involved more widely in BCR-ABL negative CML we analysed 40 cases by RT-PCR. Two cases were positive for the FLT3 internal tandem duplication (ITD) but mutation of residue D835 was not observed. Expression of the SPTBN1-FLT3 fusion transformed the interleukin 3 (IL-3)-dependent cell line Ba/F3 to growth factor independence and was accompanied by constitutive phosphorylation of the fusion protein and the downstream substrate ERK1/2. The growth of transformed cells was inhibited in a dose-dependent fashion by SU11567 and PKC142, but not by imatinib mesylate. The patient was initially treated with hydroxyurea and subsequently underwent an unrelated donor bone marrow transplant. She relapsed cytogenetically at 4 years but responded to donor lymphocyte infusion (DLI), achieving sustained cytogenetic and molecular (nested RT-PCR) remission. We conclude that SPTBN1-FLT3 is a rare abnormality in BCR-ABL negative CML that is responsive to both targeted signal transduction therapy and immunotherapy by DLI
A Polymorphism Study on Detoxification and DNA Repair Genes in 700 MDS Patients Demonstrates An Association Between Genotype and An Aberrant Karyotype.
Going Beyond Counting First Authors in Author Co-citation Analysis
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
“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
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
Dispelling the Myths Behind First-author Citation Counts
We 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
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