130,632 research outputs found
Differential rates of somatic hypermutation in V(H) genes among subsets of chronic lymphocytic leukemia defined by chromosomal abnormalities
No full textChronic lymphocytic leukemia (CLL) is a B-cell tumor involving small lymphocytes that generally express the CD5 antigen and low levels of surface Ig. Within this definition, there is heterogeneity among cases in cell morphology, karyotypic abnormalities, and clinical course. Trisomy 12, the most frequent karyotypic abnormality, is commonly found in a subset of CLL with atypical morphology. It has also been associated with advanced disease, and possibly with a less favorable prognosis. A further subset of cases with abnormalities involving chromosome 13q14 have typical lymphocyte morphology. Occasionally, the two abnormalities are found together. To assess the clonal history of the cell of origin in disease subsets defined by these two chromosomal abnormalities, we investigated the usage of VH genes and the pattern of somatic mutation in 10 cases of trisomy 12 with atypical morphology and eight cases of 13q14 abnormality with typical morphology. In addition, four cases with both chromosomal abnormalities were analyzed. Results confirm a common usage of the VH1 family in all subsets. However, the patterns of somatic mutation were distinct, with cases of trisomy 12 showing a minimal level of mutation (mean ± SD, 0.34% ± 0.86%) and cases of 13q14 abnormality showing significant levels (6.5% ± 1.67%). The four cases with both abnormalities showed a mixed pattern. All mutated cases had intraclonal homogeneity, and three of 10 had a pattern indicative of antigen selection. These results suggest that the clonal history of the two subsets of CLL may diffe
Translocation t(2;7)(p11.2;q21.2): a rare genetic aberration associated with B-cell lymphoproliferative disorders of marginal-zone origin
No full textLetter to the editorAliki Xochelli, Panagiotis Baliakas, Sarah Moore, Francesc Sole, Nicholas Wickham, Marta Salido, Anastasia Athanasiadou, David Oscier and Kostas Stamatopoulo
MeSH term explosion and author rank improve expert recommendations
No full textInformation overload is an often-cited phenomenon that reduces the productivity, efficiency and efficacy of scientists. One challenge for scientists is to find appropriate collaborators in their research. The literature describes various solutions to the problem of expertise location, but most current approaches do not appear to be very suitable for expert recommendations in biomedical research. In this study, we present the development and initial evaluation of a vector space model-based algorithm to calculate researcher similarity using four inputs: 1) MeSH terms of publications; 2) MeSH terms and author rank; 3) exploded MeSH terms; and 4) exploded MeSH terms and author rank. We developed and evaluated the algorithm using a data set of 17,525 authors and their 22,542 papers. On average, our algorithms correctly predicted 2.5 of the top 5/10 coauthors of individual scientists. Exploded MeSH and author rank outperformed all other algorithms in accuracy, followed closely by MeSH and author rank. Our results show that the accuracy of MeSH term-based matching can be enhanced with other metadata such as author rank
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Dispelling the Myths Behind First-author Citation Counts
No full textWe 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
Scholarly Communication and Publishing Lunch and Learn Talk #11: The ULS Open Access Author Fee Fund
No full textAt the May 2014 talk, you will learn about the ULS Open Access Author Fee Fund--what it is, why we do it, how it works, and how the program is going so far
The R&D Tax Incentives
No full textThis article sets out some background information and reflections of the author on the R&D tax incentive schemes included in the Common Corporate Tax Base (CCTB) Proposal. In particular the author analyzes the stimulus to private R&D through ad hoc tax incentives included in the CCTB Proposal and dives into the actual provisions included in the Proposal highlighting the most relevant issues connected with their design and interpretation. Moreover, the author explores the interaction between the CCTB Proposal and the granting by Member States of domestic R&D tax incentives
Association between single nucleotide polymorphism-genotype and outcome of patients with chronic lymphocytic leukemia in a randomized chemotherapy trial
No full textBACKGROUND:
There is variability in the outcome of patients with chronic lymphocytic leukemia with apparently the same stage of disease. Identifying genetic variants that influence patients' outcome and response to treatment may provide important insights into the biology of the disease.
DESIGN AND METHODS:
We investigated the possibility that genetic variation influences outcome by conducting a genome-wide analysis of 346,831 single nucleotide polymorphisms in 356 patients entered into a phase III trial comparing the efficacy of fludarabine, chlorambucil, and fludarabine with cyclophosphamide as first-line treatment. Genotypes were linked to individual patients' outcome data and response to chemotherapy. The association between genotype and progression-free survival was assessed by Cox regression analysis adjusting for treatment and clinicopathology.
RESULTS:
The strongest associations were shown for rs1949733 (ACOX3; P=8.22x10-7), rs1342899 (P=7.72×10(-7)) and rs11158493 (PPP2R5E; P=8.50×10(-7)). In addition, the 52 single nucleotide polymorphisms associated at P<10(-4) included rs438034 (CENPF; P=4.86×10(-6)), previously correlated with cancer progression, and rs2255235 (B2M; P=3.10×10(-5)) and rs2064501 (IL22RA2; P=4.81×10(-5)) which map to B-cell genes.
CONCLUSIONS:
Our findings provide evidence that genetic variation is a determinant of progression-free survival of patients with chronic lymphocytic leukemia. Specific associations warrant further analyses
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