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131.
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Jyothilakshmi Vadassery Stefanie Ranf Corinna Drzewiecki Axel Mithöfer Christian Mazars Dierk Scheel Justin Lee Ralf Oelmüller 《The Plant journal : for cell and molecular biology》2009,59(2):193-206
Calcium (Ca2+), as a second messenger, is crucial for signal transduction processes during many biotic interactions. We demonstrate that cellular [Ca2+] elevations are early events in the interaction between the plant growth‐promoting fungus Piriformospora indica and Arabidopsis thaliana. A cell wall extract (CWE) from the fungus promotes the growth of wild‐type seedlings but not of seedlings from P. indica‐insensitive mutants. The extract and the fungus also induce a similar set of genes in Arabidopsis roots, among them genes with Ca2+ signalling‐related functions. The CWE induces a transient cytosolic Ca2+ ([Ca2+]cyt) elevation in the roots of Arabidopsis and tobacco (Nicotiana tabacum) plants, as well as in BY‐2 suspension cultures expressing the Ca2+ bioluminescent indicator aequorin. Nuclear Ca2+ transients were also observed in tobacco BY‐2 cells. The Ca2+ response was more pronounced in roots than in shoots and involved Ca2+ uptake from the extracellular space as revealed by inhibitor studies. Inhibition of the Ca2+ response by staurosporine and the refractory nature of the Ca2+ elevation suggest that a receptor may be involved. The CWE does not stimulate H2O2 production and the activation of defence gene expression, although it led to phosphorylation of mitogen‐activated protein kinases (MAPKs) in a Ca2+‐dependent manner. The involvement of MAPK6 in the mutualistic interaction was shown for an mpk6 line, which did not respond to P. indica. Thus, Ca2+ is likely to be an early signalling component in the mutualistic interaction between P. indica and Arabidopsis or tobacco. 相似文献
133.
Philipsen A Feige B Hesslinger B Scheel C Ebert D Matthies S Limberger MF Kleindienst N Bohus M Lieb K 《Attention deficit and hyperactivity disorders》2009,1(1):11-18
Adult attention deficit/hyperactivity disorder (ADHD) and borderline personality disorder (BPD) share several clinical features, e.g. emotional lability and impulsivity. This study aimed to delineate differences and similarities between ADHD and BPD with respect to borderline typical symptomatology and gender specifics. Borderline symptomatology was assessed in 60 adult patients with ADHD with the borderline symptom list (BSL) and compared to both 60 gender- and age-matched BPD patients and control subjects. The BSL is a standardized instrument including 95 items on 7 subscales (self-perception, affect regulation, self-destruction, dysphoria, loneliness, intrusions and hostility). Adult ADHD patients showed significantly higher BSL total scores and all of the seven subscales compared to healthy controls (p < 0.001) but lower scores than BPD patients (p < 0.001). With respect to the seven subscales, the largest differences between ADHD and BPD patients were found with respect to self-destruction (d = 1.12) and affect dysregulation (d = 0.90), whereas the smallest difference was found with respect to loneliness (d = 0.36). In females, the BSL subscales "loneliness" and "hostility" did not differentiate between BPD and ADHD. Borderline typical symptoms are common in adult patients with ADHD but seem to be less pronounced than in patients with BPD. Females with ADHD and BPD share more clinical features than males. However, symptoms of self-destruction and affect dysregulation appear to be more severe in BPD patients. 相似文献
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Wolf T Niehaus-Rolf C Banduhn N Eschrich D Scheel J Luepke NP 《Mutation research》2008,650(2):150-164
The hen's egg test for micronucleus induction (HET-MN) combines the use of the commonly accepted genetic endpoint "formation of micronuclei" with the well-characterized and complex model of the incubated hen's egg, which enables metabolic activation, elimination and excretion of xenobiotics -- including those that are mutagens or promutagens. This assay procedure is in line with demands for animal protection. In three previous publications we presented the scientific rationale and methodological aspects for this assay as well as results for some well-characterized mutagens and promutagens. Here we present the results of new experiments involving further genotoxic and non-genotoxic model substances. Making a comparison with published data we have to date not found any false negatives or false positives in the experiments presented here and in trials published before, thus demonstrating a promising predictivity of genotoxic effects with this assay. We could confirm relevant genotoxicity for the following substances in the HET-MN: acetylamino-fluorene (2-AAF), acrylamide (ACM), cytarabine (AraC), methotrexate (MTX), cadmium chloride (CD), dipotassium monochromate (DPC), and epirubicine (EPI). Negative results were obtained for azorubin (E122), orange G (OG) and starch (STRC). The micronucleus frequencies (MNE II) of the concurrent negative controls were in agreement with the values of the historical negative control (0.87 per thousand+/-0.87; average+/-s.d.). This value is based upon the scoring of 556,500 erythrocytes from 445 eggs. In historical positive controls the administration of 0.05mg cyclophosphamide/egg at d8 resulted in an MNE II-frequency of 12.4 per thousand+/-6.8 (average+/-s.d.) at d 10.5. This value is based upon the scoring of 249,250 erythrocytes from 223 eggs. 相似文献
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137.
Landtag J Baumert A Degenkolb T Schmidt J Wray V Scheel D Strack D Rosahl S 《Phytochemistry》2002,60(7):683-689
As part of the response to pathogen infection, potato plants accumulate soluble and cell wall-bound phenolics such as hydroxycinnamic acid tyramine amides. Since incorporation of these compounds into the cell wall leads to a fortified barrier against pathogens, raising the amounts of hydroxycinnamic acid tyramine amides might positively affect the resistance response. To this end, we set out to increase the amount of tyramine, one of the substrates of the hydroxycinnamoyl-CoA:tyramine N-(hydroxycinnamoyl)-transferase reaction, by placing a cDNA encoding a pathogen-induced tyrosine decarboxylase from parsley under the control of the 35S promoter and introducing the construct into potato plants via Agrobacterium tumefaciens-mediated transformation. While no alterations were observed in the pattern and quantity of cell wall-bound phenolic compounds in transgenic plants, the soluble fraction contained several new compounds. The major one was isolated and identified as tyrosol glucoside by liquid chromatography-electrospray ionization-high resolution mass spectrometry and NMR analyses. Our results indicate that expression of a tyrosine decarboxylase in potato does not channel tyramine into the hydroxycinnamoyl-CoA:tyramine N-(hydroxycinnamoyl)-transferase reaction but rather unexpectedly, into a different pathway leading to the formation of a potential storage compound. 相似文献
138.
Dierk?BlomeierEmail author Max?Wisshak Winfried?Dallmann Eden?Volohonsky André?Freiwald 《Facies》2003,49(1):151-174
Summary The object of this paper is to provide a facies guide that helps subsequent workers recognizing different facies and palaeoenvironments
of the terrestrial old Red Sandstone exposed in central N Spitsbergen. Sediments of the Early Devonian Wood Bay Formation
represent continental molasse deposition under arid to semi-arid climatic conditions in three main depositional environments
(rivers, alluvial plains, perennial lakes) represented by characteristic lithologies, sedimentary structures and microfacies.
River channel deposits, consisting of conglomerates, very coarse-to very fine-grained sandstones and sandy siltstones are
generally arranged in successive fining-upward sequences marked by specific sedimentary structures in a particular order.
The sediments reflect the bed, mixed and suspended load of low sinuosity braided to high sinuosity meandering rivers.
Adjacent overbank areas (levees, crevasse splays) and extensive alluvial plains are represented by reddish-brown, fine-grained
sandstones to sandy siltstones and silty mudstones. The sediments are the accumulated, mixed and suspended load of floodwaters,
which recurrently inundated the lowlands. Various lithofacies types, facies associations and sequences reflect the local formation
of palaeosols, ephemeral flood lakes and boggy areas with persistent high water tables.
Multicoloured, calcareous successions and single lime-stone beds intercalated in the red beds represent the depositional products
of perennial, low relief, low-energy lakes, which developed in topographic depressions of the alluvial plains. The sediments
reflect deposition in deep-water, littoral and palustrine sub-environments, forming regressive, shallowing-upward sequences
in the central lake areas.
The overall arrangement of the various facies reflects a terrestrial basin that developed from a steep-sloped, high-energy,
river-dominated molasse trough into a level, lowenergy coastal plain, marked by broad mud flats and the formation of extensive
perennial lakes. 相似文献
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