Evolution of IgE responses to multiple allergen components throughout childhood

BACKGROUND: There is a paucity of information about longitudinal patterns of IgE responses to allergenic proteins (components) from multiple sources. OBJECTIVE: To investigate temporal patterns of component-specific IgE responses from infancy to adolescence, and their relationship with allergic diseases. METHODS: In a population-based birth cohort, we measured IgE to 112 components at 6 follow-ups during childhood. We used a Bayesian method to discover cross-sectional sensitization patterns and their longitudinal trajectories, and related these patterns to asthma and rhinitis in adolescence. RESULTS: We identified one sensitization cluster at age one, 3 at age three, 4 at ages five and eight, 5 at age 11, and six at age 16 years. "Broad" cluster was the only cluster present at every follow-up, comprising of components from multiple sources. "Dust mite" cluster formed at age three and remained unchanged to adolescence. At age three, a single-component "Grass" cluster emerged, which at age five absorbed additional grass components and Fel d 1 to form the "Grass/cat" cluster. Two new clusters formed at age 11: "Cat" cluster and "PR-10/profilin" (which divided at age 16 into "PR-10" and "Profilin"). The strongest contemporaneous associate of asthma at age 16 years was sensitization to "Dust mite" cluster (OR [95% CI]: 2.6 [1.2-6.1], P<0.05), but the strongest early-life predictor of subsequent asthma was sensitization to "Grass/cat" cluster (3.5 [1.6-7.4], P<0.01). CONCLUSIONS: We describe the architecture of the evolution of IgE responses to multiple allergen components throughout childhood, which may facilitate development of better diagnostic and prognostic biomarkers for allergic diseases

Spatial modeling of brain connectivity data via latent distance models with nodes clustering

Brain network data—measuring structural interconnections among brain regions of interest—are increasingly collected for multiple individuals. Moreover, recent analyses provide additional information on the brain regions under study. These predictors typically include the three‐dimensional anatomical coordinates of the regions, and their membership to hemispheres and lobes. Although recent studies have explored the spatial effects underlying brain networks, there is still a lack of statistical analyses on the net connectivity structure which is not explained by the physical proximity of the brain regions. We answer this question via a predictor‐dependent latent space model for replicated brain network data which provides a meaningful representation for the net connectivity architecture via a set of latent positions having a mixture of Gaussians prior. This model allows for flexible inference on brain network patterns which are not explained by the anatomical structure, and facilitates clustering among brain regions according to local similarities in the latent space. Our findings offer novel insights on wiring mechanisms among subsets of brain regions which interestingly departs from the anatomical proximity structure

Determination of stilbene derivatives in Burgundy red wines by ultra-high-pressure liquid chromatography.

The polyphenols, for example stilbenes and flavonoids, are an important family of compounds present in grapes and wines. Several studies have shown that stilbenes are antioxidants and cancer-preventing agents. For the first time, eight natural stilbenes (trans-resveratrol, trans-piceid, cis-piceid, trans-astringin, trans-piceatannol, (+)-trans-&epsilon;-viniferin, pallidol, and hopeaphenol), isolated and purified from Vitis vinifera, were simultaneously analysed by ultra-high-pressure liquid chromatography coupled with photodiode-array detection. Separation of the stilbenes by UHPLC was optimized with the assistance of &quot;Quality-by-Design&quot; commercial software. Four different reversed-phase columns packed with 1.5-1.7-&mu;m particles were tested and compared for their retention behaviour and separation efficiency. On the basis of the performance characteristics determined, the VisionHT C18 HL column was selected for the stilbenes studied, because resolution of the critical pair was 1.5 with a peak width of 2-4 s. The optimized method resulted in highly repeatable retention times (RSD 0.03-0.07%), peak areas (RSD 3-6%), and linear ranges were between 0.005 and 50 mg L-1 for most of the compounds. All stilbenes, except trans-astringin, trans-piceatannol, and pallidol were identified and quantified in Burgundy red wines at different concentrations after direct injection of the wines. [Figure not available: see fulltext.] &copy; 2011 Springer-Verlag