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861.
Evidence is accruing that, in comprehending language, the human brain rapidly integrates a wealth of information sources–including the reader or hearer’s knowledge about the world and even his/her current mood. However, little is known to date about how language processing in the brain is affected by the hearer’s knowledge about the speaker. Here, we investigated the impact of social attributions to the speaker by measuring event-related brain potentials while participants watched videos of three speakers uttering true or false statements pertaining to politics or general knowledge: a top political decision maker (the German Federal Minister of Finance at the time of the experiment), a well-known media personality and an unidentifiable control speaker. False versus true statements engendered an N400 - late positivity response, with the N400 (150–450 ms) constituting the earliest observable response to message-level meaning. Crucially, however, the N400 was modulated by the combination of speaker and message: for false versus true political statements, an N400 effect was only observable for the politician, but not for either of the other two speakers; for false versus true general knowledge statements, an N400 was engendered by all three speakers. We interpret this result as demonstrating that the neurophysiological response to message-level meaning is immediately influenced by the social status of the speaker and whether he/she has the power to bring about the state of affairs described. 相似文献
862.
Cornelia Then Simone Wahl Anna Kirchhofer Harald Grallert Susanne Krug Gabi Kastenmüller Werner R?misch-Margl Melina Claussnitzer Thomas Illig Margit Heier Christa Meisinger Jerzy Adamski Barbara Thorand Cornelia Huth Annette Peters Cornelia Prehn Ina Heukamp Helmut Laumen Andreas Lechner Hans Hauner Jochen Seissler 《PloS one》2013,8(10)
863.
Sarah Kretschmer Ina Dethlefsen Stefanie Hagner-Benes Leigh M. Marsh Holger Garn Peter K?nig 《PloS one》2013,8(2)
Background
Lymphatic vessels play a pivotal role in fluid drainage and egress of immune cells from the lung. However, examining murine lung lymphatics is hampered by the expression of classical lymph endothelial markers on other cell types, which hinders the unambiguous identification of lymphatics. The expression of CD90/Thy-1 on lymph endothelium was recently described and we therefore examined its suitability to identify murine pulmonary lymph vessels under healthy and inflammatory conditions.Methodology/Principal Findings
Immunohistochemistry with a monoclonal antibody against CD90.2/Thy-1.2 on 200 µm thick precision cut lung slices labeled a vascular network that was distinct from blood vessels. Preembedding immunostaining and electron microscopy verified that the anti-CD90.2/Thy-1.2 antibody labeled lymphatic endothelium. Absence of staining in CD90.1/Thy-1.1 expressing FVB mice indicated that CD90/Thy-1 was expressed on lymph endothelium and labeling was not due to antibody cross reactivity. Double-labeling immunohistochemistry for CD90/Thy-1 and α-smooth muscle actin identified two routes for lymph vessel exit from the murine lung. One started in the parenchyma or around veins and left via venous blood vessels. The other began in the space around airways or in the space between airways and pulmonary arteries and left via the main bronchi. As expected from the pulmonary distribution of lymph vessels, intranasal application of house dust mite led to accumulation of T cells around veins and in the connective tissue between airways and pulmonary arteries. Surprisingly, increased numbers of T cells were also detected around intraacinar arteries that lack lymph vessels. This arterial T cell sheath extended to the pulmonary arteries where lymph vessels were located.Conclusions/Significance
These results indicate that CD90/Thy-1 is expressed on lymphatic endothelial cells and represents a suitable marker for murine lung lymph vessels. Combining CD90/Thy-1 labeling with precision cut lung slices allows visualizing the anatomy of the lymphatic system in normal and inflamed conditions. 相似文献864.
Hans-Peter Müller Jan Kassubek Ina Vernikouskaya Albert C. Ludolph Detlef Stiller Volker Rasche 《PloS one》2013,8(6)
Introduction
Fast in-vivo high resolution diffusion tensor imaging (DTI) of the mouse brain has recently been shown to enable cohort studies by the combination of appropriate pulse sequences and cryogenically cooled resonators (CCR). The objective of this study was to apply this DTI approach at the group level to β-amyloid precursor protein (APP) transgenic mice.Methods
Twelve mice (5 wild type, 7 APP transgenic tg2576) underwent DTI examination at 1562×250 µm3 spatial resolution with a CCR at ultrahigh field (11.7 T). Diffusion images were acquired along 30 gradient directions plus 5 references without diffusion encoding with a total acquisition time of 35 minutes. Fractional anisotropy (FA) maps were statistically compared by whole brain-based spatial statistics (WBSS) at the group level vs. wild type controls.Results
FA-map comparison showed characteristic regional patterns of differences between the groups with localizations associated with Alzheimer’s disease in humans, such as the hippocampus, the entorhinal cortex, and the caudoputamen.Conclusion
In this proof-of-principle study, regions associated with amyloid-β deposition could be identified by WBSS of FA maps in APP transgenic mice vs. wild type mice. Thus, DTI in the mouse brain acquired at 11.7 T by use of a CCR was demonstrated to be feasible for cohort studies. 相似文献865.
Corneal epithelial wound repair involves the migration of epithelial cells to cover the defect followed by the proliferation of the cells to restore thickness. Heparan sulfate proteoglycans (HSPGs) are ubiquitous extracellular molecules that bind to a plethora of growth factors, cytokines, and morphogens and thereby regulate their signaling functions. Ligand binding by HS chains depends on the pattern of four sulfation modifications, one of which is 6-O-sulfation of glucosamine (6OS). SULF1 and SULF2 are highly homologous, extracellular endosulfatases, which post-synthetically edit the sulfation status of HS by removing 6OS from intact chains. The SULFs thereby modulate multiple signaling pathways including the augmentation of Wnt/ß-catenin signaling. We found that wounding of mouse corneal epithelium stimulated SULF1 expression in superficial epithelial cells proximal to the wound edge. Sulf1−/−, but not Sulf2−/−, mice, exhibited a marked delay in healing. Furthermore, corneal epithelial cells derived from Sulf1−/− mice exhibited a reduced rate of migration in repair of a scratched monolayer compared to wild-type cells. In contrast, human primary corneal epithelial cells expressed SULF2, as did a human corneal epithelial cell line (THCE). Knockdown of SULF2 in THCE cells also slowed migration, which was restored by overexpression of either mouse SULF2 or human SULF1. The interchangeability of the two SULFs establishes their capacity for functional redundancy. Knockdown of SULF2 decreased Wnt/ß-catenin signaling in THCE cells. Extracellular antagonists of Wnt signaling reduced migration of THCE cells. However in SULF2- knockdown cells, these antagonists exerted no further effects on migration, consistent with the SULF functioning as an upstream regulator of Wnt signaling. Further understanding of the mechanistic action of the SULFs in promoting corneal repair may lead to new therapeutic approaches for the treatment of corneal injuries. 相似文献
866.
The plasma membrane potential is mainly considered as the driving force for ion and nutrient translocation. Using the yeast Saccharomyces cerevisiae as a model organism, we have discovered a novel role of the membrane potential in the organization of the plasma membrane. Within the yeast plasma membrane, two non-overlapping sub-compartments can be visualized. The first one, represented by a network-like structure, is occupied by the proton ATPase, Pma1, and the second one, forming 300-nm patches, houses a number of proton symporters (Can1, Fur4, Tat2 and HUP1) and Sur7, a component of the recently described eisosomes. Evidence is presented that sterols, the main lipid constituent of the plasma membrane, also accumulate within the patchy compartment. It is documented that this compartmentation is highly dependent on the energization of the membrane. Plasma membrane depolarization causes reversible dispersion of the H(+)-symporters, not however of the Sur7 protein. Mitochondrial mutants, affected in plasma membrane energization, show a significantly lower degree of membrane protein segregation. In accordance with these observations, depolarized membranes also considerably change their physical properties (detergent sensitivity). 相似文献
867.
Young Ou Camila Dores Jose-Rafael Rodriguez-Sosa Frans A. van der Hoorn Ina Dobrinski 《Cell and tissue research》2014,358(2):597-605
In vertebrates, a variety of cell types generate a primary cilium. Cilia are implicated in determination and differentiation of a wide variety of organs and during embryonic development. However, there is little information on the presence or function of primary cilia in the mammalian testis. Therefore, the objective of this study was to characterize expression of primary cilia in the developing pig testis. Testicular tissue from pigs at 2–10 weeks of age was analyzed for primary cilia by immunocytochemistry. Expression of primary cilia was also analyzed in testicular tissue formed de novo from a single cell suspension ectopically grafted into a mouse host. Functionality of primary cilia was monitored based on cilia elongation after exposure to lithium. Analysis showed that the primary cilium is present in testis cords as well as in the interstitium of the developing pig testis. Germ cells did not express primary cilia. However, we identified Sertoli cells as one of the somatic cell types that produce a primary cilium within the developing testis. Primary cilium expression was reduced from the second to the third week of pig testis development in situ and during de novo morphogenesis of testis tissue from a single cell suspension after xenotransplantation. In vitro, primary cilia were elongated in response to lithium treatment. These results indicate that primary cilia on Sertoli cells may function during testicular development. De novo morphogenesis of testis tissue from single cell suspensions may provide an accessible platform to study and manipulate expression and function of primary cilia. 相似文献
868.
Parthenogenetic lineages may colonize marginal areas of the range of related sexual species or coexist with sexual species in the same habitat. Frozen-Niche-Variation and General-Purpose-Genotype are two hypotheses suggesting that competition and interclonal selection result in parthenogenetic populations being either genetically diverse or rather homogeneous. The cosmopolitan parthenogenetic oribatid mite Oppiella nova has a broad ecological phenotype and is omnipresent in a variety of habitats. Morphological variation in body size is prominent in this species and suggests adaptation to distinct environmental conditions. We investigated genetic variance and body size of five independent forest - grassland ecotones. Forests and grasslands were inhabited by distinct genetic lineages with transitional habitats being colonized by both genetic lineages from forest and grassland. Notably, individuals of grasslands were significantly larger than individuals in forests. These differences indicate the presence of specialized genetic lineages specifically adapted to either forests or grasslands which coexist in transitional habitats. Molecular clock estimates suggest that forest and grassland lineages separated 16-6 million years ago, indicating long-term persistence of these lineages in their respective habitat. Long-term persistence, and morphological and genetic divergence imply that drift and environmental factors result in the evolution of distinct parthenogenetic lineages resembling evolution in sexual species. This suggests that parthenogenetic reproduction is not an evolutionary dead end. 相似文献
869.
Yvonne Ritze Gy?ngyi Bárdos Anke Claus Veronika Ehrmann Ina Bergheim Andreas Schwiertz Stephan C. Bischoff 《PloS one》2014,9(1)