166 research outputs found
Adjusted Measures for Feature Selection Stability for Data Sets with Similar Features
For data sets with similar features, for example highly correlated features,
most existing stability measures behave in an undesired way: They consider
features that are almost identical but have different identifiers as different
features. Existing adjusted stability measures, that is, stability measures
that take into account the similarities between features, have major
theoretical drawbacks. We introduce new adjusted stability measures that
overcome these drawbacks. We compare them to each other and to existing
stability measures based on both artificial and real sets of selected features.
Based on the results, we suggest using one new stability measure that considers
highly similar features as exchangeable
Political boundary spanning:politicians at the interface between collaborative governance and representative democracy
Research finds that productive interfaces between collaborative and bureaucratic forms of governance hinges on the extent t
TNFR1 and TNFR2 regulate the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms
The huge majority of myeloma cell lines express TNFR2 while a substantial subset of them failed to show TNFR1 expression. Stimulation of TNFR1 in the TNFR1-expressing subset of MM cell lines had no or only a very mild effect on cellular viability. Surprisingly, however, TNF stimulation enhanced cell death induction by CD95L and attenuated the apoptotic effect of TRAIL. The contrasting regulation of TRAIL- and CD95L-induced cell death by TNF could be traced back to the concomitant NFÎșB-mediated upregulation of CD95 and the antiapoptotic FLIP protein. It appeared that CD95 induction, due to its strength, overcompensated a rather moderate upregulation of FLIP so that the net effect of TNF-induced NFÎșB activation in the context of CD95 signaling is pro-apoptotic. TRAIL-induced cell death, however, was antagonized in response to TNF because in this context only the induction of FLIP is relevant. Stimulation of TNFR2 in myeloma cells leads to TRAF2 depletion. In line with this, we observed cell death induction in TNFR1-TNFR2-costimulated JJN3 cells. Our studies revealed that the TNF-TNF receptor system adjusts the responsiveness of the extrinsic apoptotic pathway in myeloma cells by multiple mechanisms that generate a highly context-dependent net effect on myeloma cell survival
Citrullination of histone H3 drives IL-6 production by bone marrow mesenchymal stem cells in MGUS and multiple myeloma
Multiple myeloma (MM), an incurable plasma cell malignancy, requires localisation within the bone
marrow. This microenvironment facilitates crucial interactions between the cancer cells and stromal
cell types that permit the tumour to survival and proliferate. There is increasing evidence that the
bone marrow mesenchymal stem cell (BMMSC) is stably altered in patients with MM â a phenotype
also postulated to exist in patients with monoclonal gammopathy of undetermined significance
(MGUS) a benign condition that precedes MM. In this study, we describe a mechanism by which
increased expression of peptidyl arginine deiminase 2 (PADI2) by BMMSCs in patients with MGUS
and MM directly alters malignant plasma cell phenotype. We identify PADI2 as one of the most
highly upregulated transcripts in BMMSCs from both MGUS and MM patients, and that through its
enzymatic deimination of histone H3 arginine 26, PADI2 activity directly induces the upregulation of
interleukin-6 (IL-6) expression. This leads to the acquisition of resistance to the chemotherapeutic
agent, bortezomib, by malignant plasma cells. We therefore describe a novel mechanism by which
BMMSC dysfunction in patients with MGUS and MM directly leads to pro-malignancy signalling
through the citrullination of histone H3R26
Distinct Genetic Architectures for Male and Female Inflorescence Traits of Maize
We compared the genetic architecture of thirteen maize morphological traits in a large population of recombinant inbred lines. Four traits from the male inflorescence (tassel) and three traits from the female inflorescence (ear) were measured and studied using linkage and genome-wide association analyses and compared to three flowering and three leaf traits previously studied in the same population. Inflorescence loci have larger effects than flowering and leaf loci, and ear effects are larger than tassel effects. Ear trait models also have lower predictive ability than tassel, flowering, or leaf trait models. Pleiotropic loci were identified that control elongation of ear and tassel, consistent with their common developmental origin. For these pleiotropic loci, the ear effects are larger than tassel effects even though the same causal polymorphisms are likely involved. This implies that the observed differences in genetic architecture are not due to distinct features of the underlying polymorphisms. Our results support the hypothesis that genetic architecture is a function of trait stability over evolutionary time, since the traits that changed most during the relatively recent domestication of maize have the largest effects
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