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Prairie restorations typically differ from remnant prairies in forb composition; long‐lived, late‐successional plants are often missing. To study establishment of such species, we set up a field experiment where seeds of the threatened, long‐lived Asclepias meadii were sown individually into the field with initial fire and soil disturbance treatments. We returned each year for 11 years to record the presence/absence, size, and reproduction of each plant. Individual plants were sometimes observed 1 year, not observed a subsequent year, and then observed again. We therefore analyzed survival data with mark‐recapture models and found that the probability of a seed germinating and the resulting plant surviving for 11 years was 0.057 (5.7%). Probability of detection was approximately 0.80, suggesting that we did not observe all living plants. Vegetative dormancy, herbivory on above‐ground parts, and observer error could all be responsible. We found no relationship between plant survival and the initial burn/disturbance treatment or previous year precipitation. Plants that were observed in the last study year were individuals that had, on average, greater size in earlier years. Three plants produced flowers and two produced fruit; we believe such reproductive success has not been previously documented for seed of A. meadii sowed into a restoration site. Our restoration study dovetails with the more typical plant community restoration research. In such studies, seeds of many species are sown, but often the late successional species do not establish. We show the value of detailed multiyear monitoring to determine the fate of such plant introductions. [ABSTRACT FROM AUTHOR]

Background: Atopic dermatitis (AD) is a frequent and heterogeneous inflammatory skin disease, for which personalized medicine remains a challenge. High‐throughput approaches have improved understanding of the complex pathophysiology of AD. However, a purely data‐driven AD classification is still lacking. Methods: To address this question, we applied an original unsupervised approach on the largest available transcriptome dataset of AD lesional (n = 82) and healthy (n = 213) skin biopsies. Results: Taking into account pathological and physiological state, a variance‐based filtering revealed 222 AD‐specific hyper‐variable genes that efficiently classified the AD samples into 4 clusters that turned out to be clinically and biologically distinct. Comparison of gene expressions between clusters identified 3 sets of upregulated genes used to derive metagenes (MGs): MG‐I (19 genes) was associated with IL‐1 family signaling (including IL‐36A and 36G) and skin remodeling, MG‐II (23 genes) with negative immune regulation (including IL‐34 and 37) and skin architecture, and MG‐III (17 genes) with B lymphocyte immunity. Sample clusters differed in terms of disease severity (p =.02) and S. aureus (SA) colonization (p =.02). Cluster 1 contained the most severe AD, highest SA colonization, and overexpressed MG‐I. Cluster 2 was characterized by less severe AD, low SA colonization, and high MG‐II expression. Cluster 3 included mild AD, mild SA colonization, and mild expression of all MGs. Cluster 4 had the same clinical features as cluster 3 but had hyper‐expression of MG‐III. Last, we successfully validated our method and results in an independent cohort. Conclusion: Our study revealed unrecognized AD endotypes with specific underlying biological pathways, highlighting novel pathophysiological mechanisms. These data could provide new insights into personalized treatment strategies. [ABSTRACT FROM AUTHOR]

Dietary flaxseed has been shown to have potent antiatherogenic effects in rabbits. The purpose of the present study was to investigate the antiatherogenic capacity of flaxseed in an animal model that more closely represents the human atherosclerotic condition, the LDL receptor-deficient mouse (LDLrKO), and to identify the cellular mechanisms for these effects. LDLrKO mice were administered a regular diet (RG), a 10% flaxseed-supplemented diet (FX), or an atherogenic diet containing 2% cholesterol alone (CH) or supplemented with 10% flaxseed (CF), 5% flaxseed (CF5), 1% flaxseed (CF1), or 5% coconut oil (CS) for 24 wk. LDLrKO mice fed a cholesterol-supplemented diet exhibited a rise in plasma cholesterol without a change in triglycerides and an increase in atherosclerotic plaque formation. The CS mice exhibited elevated levels of plasma cholesterol, triglycerides, and saturated fatty acids and an increase in plaque development. Supplementation of the cholesterol-enriched diet with 10% (wt/wt) ground flaxseed lowered plasma cholesterol and saturated fatty acids, increased plasma ALA, and inhibited plaque formation in the aorta and aortic sinus compared with mice fed a diet supplemented with only dietary cholesterol. The expression of proliferating cell nuclear antigen (PCNA) and the inflammatory markers IL-6, mac-3, and VCAM-1 was increased in aortic tissue from CH and CS mice. This expression was significantly reduced or normalized when flaxseed was included in the diet. Our results demonstrate that dietary flaxseed can inhibit atherosclerosis in the LDLrKO mouse through a reduction of circulating cholesterol levels and, at a cellular level, via antiproliferative and anti-inflammatory actions. linseed; nutrition; [alpha]-linolenic acid; cardiovascular disease; inflammation

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1365-2745.2007.01254.x Byline: JENNIFER MOODY-WEIS, HELEN M. ALEXANDER Keywords: crop-wild hybrids; density-dependence; fate of seeds; Helianthus annuus; seed bank; seed burial; soil disturbance; sunflowers Abstract: Summary Seed banks are important to many plant populations, yet we lack clear understanding of how environmental factors promote seed bank formation. We experimentally varied seed density, and soil disturbance size and timing, to examine the formation of seed banks and the resulting population dynamics in wild annual sunflowers (Helianthus annuus). Seed density treatments reflected the expected increase in seed production of individual wild sunflowers due to hybridization with Bt-transgenic crop sunflowers. Soil disturbances of two sizes (large and small) were applied either before or after seed dispersal. We followed the experimental plots for 2.sup.1/.sub.2 years measuring seedling emergence, seeds in the soil, and reproduction, while preventing additional seed input. We assessed seed bank formation by the numbers of emergent seedlings and seeds in the soil. Soil disturbances, regardless of timing, were required for successful germination and reproduction of wild sunflowers. Large disturbances resulted in greater seedling emergence and reproduction than small disturbances. Reproduction on small disturbance plots was low, due to low seedling survival. Higher seed density resulted in more seedlings only in large-disturbance plots. Post-dispersal disturbances led to significant seed bank formation. This effect was greater for large, post-dispersal disturbances. Higher seed density increased seed bank size only in the presence of large, post-dispersal disturbances. Negative density-dependence in seedling mortality and reproduction meant that there was no effect of the high seed density treatment on reproduction. Thus the positive effects of increased seed bank size on population growth were tempered by density-dependence. To assess fully the impact of seed banks on population growth, studies should continue beyond the seedling stage. Our results suggest increased seed production of individual sunflowers resulting from crop transgenes would be unlikely to increase population growth on the scale of small patches. Increased seed production could result in dispersal of seeds across larger areas, and thus could lead to larger seed banks in disturbed environments and an increased prevalence of sunflowers across the landscape. These results are relevant to other annual species, especially those with transgenic crop relatives. Article History: Received 11 July 2006; revision accepted 28 March 2007 Handling Editor: Scott Collins Article note: Correspondence: Jennifer Moody-Weis (e-mail jmweis@ku.edu).