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Contiguous Regions (contiguous + regions)
Selected AbstractsA variant of the myosin light chain kinase gene is associated with severe asthma in African AmericansGENETIC EPIDEMIOLOGY, Issue 4 2007Carlos Flores Abstract Asthma is a complex phenotype influenced by environmental and genetic factors for which severe irreversible structural airway alterations are more frequently observed in African Americans. In addition to a multitude of factors contributing to its pathobiology, increased amounts of myosin light chain kinase (MLCK), the central regulator of cellular contraction, have been found in airway smooth muscle from asthmatics. The gene encoding MLCK (MYLK) is located in 3q21.1, a region noted by a number of genome-wide studies to show linkage with asthma and asthma-related phenotypes. We studied 17 MYLK genetic variants in European and African Americans with asthma and severe asthma and identified a single non-synonymous polymorphism (Pro147Ser) that was almost entirely restricted to African populations and which was associated with severe asthma in African Americans. These results remained highly significant after adjusting for proportions of ancestry estimated using 30 unlinked microsatellites (adjusted odds ratio: 1.76 [95% confidence interval, CI: 1.17,2.65], p = 0.005). Since all common HapMap polymorphisms in ,500,kb contiguous regions have low-to-moderate linkage disequilibrium with Pro147Ser, we speculate that this polymorphism is causally related to the severe asthma phenotype in African Americans. The association of this polymorphism, located in the N-terminal region of the non-muscle MLCK isoform, emphasizes the potential importance of the vascular endothelium, a tissue in which MLCK is centrally involved in multiple aspects of the inflammatory response, in the pathogenesis of severe asthma. This finding also offers a possible genetic explanation for some of the more severe asthma phenotype observed in African American asthmatics. Genet Epidemiol 2007. © 2007 Wiley-Liss, Inc. [source] Languages for constrained binary segmentation based on maximum a posteriori probability labeling,INTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2009Abstract We use a MRF with asymmetric pairwise compatibility constraints between direct pixel neighbors to solve a constrained binary image segmentation task. The model is constraining shape and alignment of individual contiguous binary segments by introducing auxiliary labels and their pairwise interactions. Such representation is not necessarily unique. We study several ad-hoc labeling models for binary images consisting of nonoverlapping rectangular contiguous regions. Nesting and equivalence of these models are studied. We observed a noticeable increase in performance even in cases when the differences between the models were seemingly insignificant. We use the proposed models for segmentation of windowpanes and windows in orthographically rectified façade images. Segmented window patches are always axis-parallel nonoverlapping rectangles which must also be aligned in our strongest model. We show experimentally that even very weak data model in the MAP formulation of the optimal segmentation problem gives very good segmentation results. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 69,79, 2009. [source] Connections of functional areas in the mustached bat's auditory cortex with the auditory thalamusTHE JOURNAL OF COMPARATIVE NEUROLOGY, Issue 2 2007James M. Pearson Abstract The auditory thalamus is the major target of the inferior colliculus and connects in turn with the auditory cortex. In the mustached bat, biosonar information is represented according to frequency in the central nucleus of the inferior colliculus (ICc) but according to response type in the cortex. In addition, the cortex has multiple areas with neurons of similar response type compared to the single tonotopic representation in the ICc. To investigate whether these transformations occur at the level of the thalamus, we injected anatomical tracers into physiologically defined locations in the mustached bat's auditory cortex. Injections in areas used for target ranging labeled contiguous regions of the auditory thalamus rather than separate patches corresponding to regions that respond to the different harmonic frequencies used for ranging. Injections in the two largest ranging areas produced labeling in separate locations. These results indicate that the thalamus is organized according to response type rather than frequency and that multiple mappings of response types exist. Injections in areas used for target detection labeled thalamic regions that were largely separate from those that interconnect with ranging areas. However, injections in an area used for determining target velocity overlapped with the areas connected to ranging areas and areas involved in target detection. Thus, separation by functional type and multiplication of areas with similar response type occurs by the thalamic level, but connections with the cortex segregate the functional types more completely than occurs in the thalamus. J. Comp. Neurol. 500:401,418, 2007. © 2006 Wiley-Liss, Inc. [source] Genetic structure in ixodid ticks from Kangaroo Island and the South Australia mainlandAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 1 2009Thomas W Chapman Abstract We describe here a molecular genetic study designed to elucidate the ability of an ixodid tick to move within their range as well as between species or hosts. A direct match from the contiguous regions of the small rRNA subunit, control region #1, tRNA-Ile, tRNA-Gln and tRNA-Met of the population studied here with previously published sequence suggests that the species is likely Ixodes hirsti. Phylogenetic analysis of tick haplotypes showed no evidence for bird-host specialisation, and a nested clade analysis indicated a high degree of migration between our three collection sites (two sites on Kangaroo Island, and one site on mainland South Australia). [source] | ||||||||||