Seed-derived microbial colonization of Wild Emmer and domesticated bread wheat (Triticum dicoccoides and T. aestivum) seedlings shows pronounced differences in overall diversity and composition

The composition of the plant microbiota may be altered by ecological and evolutionary changes in the host population. Seed-associated microbiota, expected to be largely vertically transferred, have the potential to coadapt with their host over generations. Strong directional selection and changes in the genetic composition of plants during domestication and cultivation may have impacted the assembly and transmission of seed-associated microbiota. Nonetheless, the effect of plant speciation and domestication on the composition of these microbes is poorly understood. Here, we have investigated the composition of bacteria and fungi associated with the wild emmer wheat (Triticum dicoccoides) and domesticated bread wheat (Triticum aestivum). We show that vertically transmitted bacteria, but not fungi, of domesticated bread wheat species T. aestivum are less diverse and more inconsistent among individual plants compared to those of the wild emmer wheat species T. dicoccoides. We propagated wheat seeds under sterile conditions to characterize the colonization of seedlings by seed-associated microbes. Hereby, we show markedly different community compositions and diversities of leaf and root colonizers of the domesticated bread wheat compared to the wild emmer wheat. By propagating the wild emmer wheat and domesticated bread wheat in two different soils, we furthermore reveal a small effect of plant genotype on microbiota assembly. Our results suggest that domestication and prolonged breeding have impacted the vertically transferred bacteria, but only to a lesser extent have affected the soil-derived microbiota of bread wheat.IMPORTANCE Genetic and physiological changes associated with plant domestication have been studied for many crop species. Still little is known about the impact of domestication on the plant-associated microbiota. In this study, we analyze the seed-associated and soil-derived bacterial and fungal microbiota of domesticated bread wheat and wild emmer wheat. We show a significant difference in the seed-associated, but not soil-derived, bacterial communities of the wheat species. Interestingly, we find less pronounced effects on the fungal communities. Overall, this study provides novel insight into the diversity of vertically transmitted microbiota of wheat and thereby contributes to our understanding of wheat as a “}metaorganism.{” Insight into the wheat microbiota is of fundamental importance for the development of improved crops

Solid solution decomposition and Guinier-Preston zone formation in Al-Cu alloys: A kinetic theory with anisotropic interactions

Using methods of statistical kinetic theory parametrized with first-principles interatomic interactions that include chemical and strain contributions, we investigated the kinetics of decomposition and microstructure formation in Al-Cu alloys as a function of temperature and alloy concentration. We show that the decomposition of the solid solution forming platelets of copper, known as Guinier-Preston (GP) zones, includes several stages and that the transition from GP1 to GP2 zones is determined mainly by kinetic factors. With increasing temperature, the model predicts a gradual transition from platelet-like precipitates to equiaxial ones and at intermediate temperatures both precipitate morphologies may coexist.Comment: 9 pages, 8 figure

Increased fibrosis in a mouse model of anti-laminin 332 mucous membrane pemphigoid remains unaltered by inhibition of aldehyde dehydrogenase

Mucous membrane pemphigoid (MMP) is an autoimmune blistering disease characterized by autoantibodies against the basal membrane zone of skin and surface-close epithelia and predominant mucosal lesions. The oral cavity and conjunctivae are most frequently affected, albeit clinical manifestations can also occur on the skin. MMP-associated lesions outside the oral cavity typically lead to scarring. Mechanisms underlying scarring are largely unknown in MMP and effective treatment options are limited. Herein, we assessed the collagen architecture in tissue samples of an antibody-transfer mouse model of anti-laminin-332 MMP. In MMP mice, increased collagen fibril density was observed in skin and conjunctival lesions compared to mice injected with normal rabbit IgG. The extracellular matrix of MMP skin samples also showed altered post-translational collagen cross-linking with increased levels of both lysine- and hydroxylysine-derived collagen crosslinks supporting the fibrotic phenotype in experimental MMP compared to control animals. In addition, we evaluated a potential anti-fibrotic therapy in experimental anti-laminin-332 MMP using disulfiram, an inhibitor of the aldehyde dehydrogenase (ALDH), which has been implicated in immune-mediated mucosal scarring. In addition, disulfiram also acts as a copper chelator that was shown to block lysyl oxidase activity, an enzyme involved in formation of collagen crosslinks. Topical use of disulfiram (300 μM in 2 [w/v] methocel) did not improve ocular lesions in experimental MMP over the 12-day treatment period in disulfiram-treated mice compared to vehicle-treated mice (n=8/group). Furthermore, C57BL6/J mice (n=8/group) were treated prophylactically with 200 mg/kg p.o. disulfiram or the solvent once daily over a period of 12 days. Systemic treatment did not show any reduction in the severity of oral and ocular lesions in MMP mice, albeit some improvement in skin lesions was observed in disulfiram- vs. vehicle-treated mice (p=0.052). No reduction in fibrosis was seen, as assessed by immunohistochemistry. Whilst blocking of ALDH failed to significantly ameliorate disease activity, our data provide new insight into fibrotic processes highlighting changes in the collagenous matrix and cross-linking patterns in IgG-mediated MMP

Inhibition of phosphodiesterase-4 significantly decreases oral mucosa lesions in experimental anti-laminin 332 mucous membrane pemphigoid

Mucous membrane pemphigoid (MMP) is characterized by autoantibodies against the dermal-epidermal-junction and a mucosal disease predominating over skin involvement. As the treatment of MMP patients still relies on high-dose corticosteroids, there is an unmet need for new and more specific therapies. Here, we made use of a recently established experimental model that recapitulated major clinical and immunopathological characteristics of human MMP by the injection of IgG against the murine alpha3 chain of laminin 332 (Lam332) into adult mice. In a prophylactic approach, the specific PDE4 inhibitor roflumilast (ROF) led in 2 independent, blinded experiments, to the reduction of oral lesions compared to vehicle-treated mice as quantified by endoscopy (p¼0.029). In contrast, an increase in skin lesions was observed in ROF-treated mice (p<0.0001). In a quasi-therapeutic approach, i.e. when ROF/vehicle was not used until mice had developed first skin lesions, ROF-treated mice showed significantly less oral lesions compared to vehicle-treated mice, while skin lesions did not differ. To investigate the discrepant effect of ROF on oral and skin lesions, a transcriptome analysis of both tissues in ROF- and vehicle-treated anti-Lam332 MMP mice as well as mice injected with normal rabbit IgG was performed. An up-regulation of IL-6 and an impact of CXCL2 were found by Gene Set Enrichment and STRING analysis, respectively, in both the skin and buccal mucosa of vehicle-treated mice. The subsequent incubation of murine keratinocytes with anti-mLam332 IgG resulted in a dose-dependent release of IL-6 and CXCL2, which was inhibited by the addition of ROF. Our data propose IL-6 and CXCL2 as relevant pathogenic factors in MMP and suggest PDE4 inhibition as potential novel treatment options for MMP patients with severe oral lesions

Comparative Genome Analysis of the Photosynthetic Betaproteobacteria of the Genus Rhodocyclus: Heterogeneity within Strains Assigned to Rhodocyclus tenuis and Description of Rhodocyclus gracilis sp. nov. as a New Species

The genome sequences for Rhodocyclus purpureus DSM 168T and four strains assigned to Rhodocyclus tenuis (DSM 110, DSM 111, DSM 112, and IM 230) have been determined. One of the strains studied (IM 230) has an average nucleotide identity (ANI) of 97% to the recently reported genome of the type strain DSM 109 of Rcy. tenuis and is regarded as virtually identical at the species level. The ANI of 80% for three other strains (DSM 110, DSM 111, DSM 112) to the type strain of Rcy. tenuis points to a differentiation of these at the species level. Rcy. purpureus is equidistant from Rcy. tenuis and the new species, based on both ANI (78–80%) and complete proteome comparisons (70% AAI). Strains DSM 110, DSM 111, and DSM 112 are very closely related to each other based on ANI, whole genome, and proteome comparisons but clearly distinct from the Rcy. tenuis type strain DSM 109. In addition to the whole genome differentiation, these three strains also contain unique genetic differences in cytochrome genes and contain genes for an anaerobic cobalamin synthesis pathway that is lacking from both Rcy. tenuis and Rcy. purpureus. Based on genomic and genetic differences, these three strains should be considered to represent a new species, which is distinctly different from both Rcy. purpureus and Rcy. tenuis, for which the new name Rhodocyclus gracilis sp. nov. is proposed

Evolution and Flare Activity of Delta-Sunspots in Cycle 23

The emergence and magnetic evolution of solar active regions (ARs) of beta-gamma-delta type, which are known to be highly flare-productive, were studied with the SOHO/MDI data in Cycle 23. We selected 31 ARs that can be observed from their birth phase, as unbiased samples for our study. From the analysis of the magnetic topology (twist and writhe), we obtained the following results. i) Emerging beta-gamma-delta ARs can be classified into three topological types as "quasi-beta", "writhed" and "top-to-top". ii) Among them, the "writhed" and "top-to-top" types tend to show high flare activity. iii) As the signs of twist and writhe agree with each other in most cases of the "writhed" type (12 cases out of 13), we propose a magnetic model in which the emerging flux regions in a beta-gamma-delta AR are not separated but united as a single structure below the solar surface. iv) Almost all the "writhed"-type ARs have downward knotted structures in the mid portion of the magnetic flux tube. This, we believe, is the essential property of beta-gamma-delta ARs. v) The flare activity of beta-gamma-delta ARs is highly correlated not only with the sunspot area but also with the magnetic complexity. vi) We suggest that there is a possible scaling-law between the flare index and the maximum umbral area

Epithelial calcineurin controls microbiota-dependent intestinal tumor development.

Inflammation-associated pathways are active in intestinal epithelial cells (IECs) and contribute to the pathogenesis of colorectal cancer (CRC). Calcineurin, a phosphatase required for the activation of the nuclear factor of activated T cells (NFAT) family of transcription factors, shows increased expression in CRC. We therefore investigated the role of calcineurin in intestinal tumor development. We demonstrate that calcineurin and NFAT factors are constitutively expressed by primary IECs and selectively activated in intestinal tumors as a result of impaired stratification of the tumor-associated microbiota and toll-like receptor signaling. Epithelial calcineurin supports the survival and proliferation of cancer stem cells in an NFAT-dependent manner and promotes the development of intestinal tumors in mice. Moreover, somatic mutations that have been identified in human CRC are associated with constitutive activation of calcineurin, whereas nuclear translocation of NFAT is associated with increased death from CRC. These findings highlight an epithelial cell-intrinsic pathway that integrates signals derived from the commensal microbiota to promote intestinal tumor development.This work was supported by the Deutsche Forschungsgemeinschaft (DFG) grants ZE814/5-1 (S.Z.), BA2863/5-1 (J.F.B.) and CH279/5-1 (T.C.), the European Research Council (ERC) starting grant 336528 (S.Z.), a Postdoctoral Fellowship Award from the Crohn's and Colitis Foundation of America (S.Z.), the European Commission (Marie Curie International Reintegration grant 256363; S.Z.), the DFG Excellence Cluster 'Inflammation at Interfaces' (S.Z. and J.F.B.), the DFG Excellence Cluster 'Center for Regenerative Therapies' (S.Z.); the US National Institutes of Health grants DK044319 (R.S.B.), DK051362 (R.S.B.), DK053056 (R.S.B.) and DK088199 (R.S.B.), the Harvard Digestive Diseases Center (HDDC) grant DK0034854 (R.S.B.), and the AIRC grant IG-14233 (M.E.B.).This is the author accepted manuscript. The final version is available from Nature Publishing Group via http://dx.doi.org/10.1038/nm.407

Procedure to determine the impact of the surface film resistance on the hygric properties of composite clay/fibre plasters

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Burnout in health-care professionals during reorganizations and downsizing. A cohort study in nurses

Background: Burnout is a psychological reaction triggered by interaction between personal characteristics and stress factors. Reorganizations and downsizing with increased workload imply stress for health-care professionals. This is a study of burnout in nurses during a period with two comprehensive reorganizations. Methods: In this quasi-experimental retrospective cohort study, burnout was assessed in nurses with long work experience in three surveys during a 30 months' period with two comprehensive reorganizations and downsizing of a hospital unit with mostly seriously ill patients with cancer. Burnout was measured with Bergen Burnout Indicator (BBI) at each survey, and "Sense of Coherence" (SOC) with Antonovsky's questionnaire at the last survey. Results: One man and 45 women aged 30 to 65 years were invited to the surveys. There was a significant increase in burnout during the study period, the mean increase in BBI-score was 12.5 pr year (p<0.001). The proportion of satisfied nurses at the first and last survey were 84% and 35% respectively, and the proportions with burnout were 0% and 29% respectively (p<0.001). Except for auxiliary nurses with experience from the medical department, all subgroups experienced a significant increase in BBI. Burnout was associated with low SOC (p<0.001, r square 0.33). Conclusions: There was a significant development of burnout in a group of nurses during a period with two reorganizations and downsizing. Burnout was associated with low SOC. Working with seriously ill patients with cancer has probably made the nurses exceptionally vulnerable to the stress and workload related to the reorganizations