Many brilliant minds are at work to decipher the biological labyrinth and as a result immense amount of information about biological entities and their relationships is getting accumulated in the form of published literature (Hunter and... more
Many brilliant minds are at work to decipher the biological labyrinth and as a result immense amount of information about biological entities and their relationships is getting accumulated in the form of published literature (Hunter and Cohen, 2006). To cater the needs of a researcher, many tools are designed to perform tasks of Named Entity Recognition (NER), Information Retrieval (IR), and Information Extraction (IE) viz. A
Huntington's Disease (HD) is an incurable disease of the adult Background: brain. Massive changes in gene expression are a prominent feature. Epigenetic effects have been reported to be implicated in HD, but the role of chromatin is not... more
Huntington's Disease (HD) is an incurable disease of the adult Background: brain. Massive changes in gene expression are a prominent feature. Epigenetic effects have been reported to be implicated in HD, but the role of chromatin is not well understood. We tested if the chromatin state of dysregulated genes in HD is affected at a genome-wide scale and examined how epigenetic processes are associated with CpG-island-mediated gene expression. Our general approach incorporates computational and functional Methods: analysis of public data before embarking on expensive wet-lab experiments. We compared the location in the genome of the genes that were deregulated in HD human brain, obtained from public gene expression data, to the location of particular chromatin marks in reference tissues using data from the ENCODE project. We found that differentially expressed genes were enriched in the Results: active chromatin state, but not enriched in the silent state. In the caudate nucleus, the most highly affected brain region in HD, genes in the active state were associated with transcription, cell cycle, protein transport and modification, RNA splicing, histone post-translational modifications and RNA processing. Genes in the repressed state were linked with developmental processes and responses related to zinc and cadmium stimulus. We confirmed that genes within CpG-islands are enriched among HD dysregulated genes in human and mouse in HD. Epigenetic processes were associated more with genes that overlap with CpG-islands than genes that do not. Our results suggest that massive transcriptional dysregulation in Conclusion: HD is not matched by large-scale relocation of gene activity, i.e. inactive chromatin regions are altered into actively expressed chromatin regions and vice versa. We expect that changes in epigenetic chromatin state might occur at the level of single genes (e.g. promoters, gene body) and scattered genomic sites (e.g. CTCF sites, enhancer regions) instead of large-scale genomic regions.
In domain-specific search systems, knowledge of a domain of interest is embedded as a backbone that guides the search process. But the knowledge used in most such systems 1. exists only for few well known broad domains; 2. is of a basic... more
In domain-specific search systems, knowledge of a domain of interest is embedded as a backbone that guides the search process. But the knowledge used in most such systems 1. exists only for few well known broad domains; 2. is of a basic nature: either purely hierarchical or involves only few relationship types; and 3. is not always kept up-to-date missing insights from recently published results. In this paper we present a framework and implementation of a focused and up-to-date knowledge-based search system, called ...