2,494 research outputs found
Analysis of epidermis- and mesophyll-specific transcript accumulation in powdery mildew-inoculated wheat leaves
Powdery mildew is an important disease of wheat caused by the obligate biotrophic fungus Blumeria graminis f. sp. tritici. This pathogen invades exclusively epidermal cells after penetrating directly through the cell wall. Because powdery mildew colonizes exclusively epidermal cells, it is of importance not only to identify genes which are activated, but also to monitor tissue specificity of gene activation. Acquired resistance of wheat to powdery mildew can be induced by a previous inoculation with the non-host pathogen B. graminis f. sp. hordei, the causal agent of barley powdery mildew. The establishment of the resistant state is accompanied by the activation of genes. Here we report the tissue-specific cDNA-AFLP analysis and cloning of transcripts accumulating 6 and 24 h after the resistance-inducing inoculation with B. graminis f. sp. hordei. A total of 25 000 fragments estimated to represent about 17 000 transcripts were displayed. Out of these, 141 transcripts, were found to accumulate after Bgh inoculation using microarray hybridization analysis. Forty-four accumulated predominantly in the epidermis whereas 76 transcripts accumulated mostly in mesophyll tissu
Transcriptional changes in powdery mildew infected wheat and Arabidopsis leaves undergoing syringolin-triggered hypersensitive cell death at infection sites
Blumeria graminis f.sp. tritici, the causal agent of powdery mildew in wheat, is an obligate biotrophic fungus that exclusively invades epidermal cells. As previously shown, spraying of a solution of syringolin A, a circular peptide derivative secreted by the phytopathogenic bacterium Pseudomonas syringae pv. syringae, triggers hypersensitive cell death at infection sites in powdery mildew infected wheat. Thus, the fungus is essentially eradicated. Here we show that syringolin A also triggers hypersensitive cell death in Arabidopsis infected with the powdery mildew fungus Erysiphe cichoracearum. To monitor transcriptional changes associated with this effect, we cloned 307 cDNA clones representing 158 unigenes from powdery mildew infected, syringolin A sprayed wheat leaves by a suppression subtractive hybridization cloning procedure. These cDNAs were microarrayed onto glass slides together with 1088 cDNA-AFLP clones from powdery mildew-infected wheat. Microarray hybridization experiments were performed with probes derived from leaves, epidermal tissue, and mesophyll preparations of mildewed or uninfected wheat plants after syringolin A or control treatment. Similar experiments were performed in Arabidopsis using the Affymetrix ATH1 whole genome GeneChip. The results indicate a conserved mode of action of syringolin A as similar gene groups are induced in both species. Prominent groups include genes associated with the proteasomal degradation pathway, mitochondrial and other heat shock genes, genes involved in mitochondrial alternative electron pathways, and genes encoding glycolytic and fermentative enzymes. Surprisingly, in both species the observed transcriptional response to syringolin A was considerably weaker in infected plants as compared to uninfected plants. The results lead to the working hypothesis that cell death observed at infection sites may result from a parasite-induced suppression of the transcriptional response and thus to insufficient production of protective proteins necessary for the recovery of these cells from whatever insult is imposed by syringolin
Vocally disruptive behavior in the elderly: a systematic review
Background: Vocally disruptive behavior (VDB) in the elderly is a common condition, especially in people with dementia, but difficult to treat. It may occur in as many as 40% of nursing home residents. This study is a review of the existing literature on this condition. Method: The literature review was conducted using PubMed (particularly Medline and the Cochrane database) and reference lists from relevant publications in English, French, and German. Results: Most studies are small and no conclusive prevalence data are available. Many biological and psychosocial treatments have been advocated, but most studies are little more than anecdotal case reports. It is evident that VDB can have deleterious consequences on others and the patients themselves, although no studies specifically examine the range or the pervasiveness of VDB. Etiopathogenic research on VDB is still in its infancy. Conclusions: Most aspects surrounding VDB are insufficiently understood. The heterogeneity and multiple contributive factors regarding VDB suggest quite convincingly that a panoply of different interventions tailored to the individual's needs will be required to overcome VDB and the suffering related to i
An integrative genetic linkage map of winter wheat ( Triticum aestivum L.)
We constructed a genetic linkage map based on a cross between two Swiss winter wheat (Triticum aestivum L.) varieties, Arina and Forno. Two-hundred and forty F5 single-seed descent (SSD)-derived lines were analysed with 112 restriction fragment length polymorphism (RFLP) anonymous probes, 18 wheat cDNA clones coding for putative stress or defence-related proteins and 179 simple-sequence repeat (SSR) primer-pairs. The 309 markers revealed 396 segregating loci. Linkage analysis defined 27 linkage groups that could all be assigned to chromosomes or chromosome arms. The resulting genetic map comprises 380 loci and spans 3,086cM with 1,131cM for the A genome, 920cM for the B genome and 1,036cM for the D genome. Seventeen percent of the loci showed a significant (P < 0.05) deviation from a 1:1 ratio, most of them in favour of the Arina alleles. This map enabled the mapping of QTLs for resistance against several fungal diseases such as Stagonospora glume blotch, leaf rust and Fusarium head blight. It will also be very useful for wheat genetic mapping, as it combines RFLP and SSR markers that were previously located on separate map
An Interview with Adolf Muschg
Adolf Muschg, a popular writer, teacher and aesthetician, is one of the comparatively few contemporary Swiss writers who has been able to establish himself firmly in Germany. In recent years, he has begun to attract the attention of American critics and Germanists as well. In the interview, Adolf Muschg deals with a wide spectrum of issues. He identifies the authors and works that mean most to him. He traces, for instance, his changing relationship to Goethe, whom he recently rediscovered. In Goethe\u27s works, above all in his scientific studies, Muschg finds issues that are of central importance to the survival of our planet. He detects a kinship between Goethe and the Greens of the seventies and looks back critically on the turbulent sixties. He provides an analysis of the current tensions between the USA and Western Europe, while confirming his keen and very personal involvement with the USA. But at the core of the interview are his extensive comments on the creative processes and the perils inherent in writing fiction. There he deals with the complex relationship between literature and therapy, the therapeutic potential of literature for the writer and the reader. By describing the novelist\u27s difficult journey on the narrow path between self-revelation and indiscretion, he also reflects upon the related issue of literary narcissism
The influence of a systematic risk assessment and a training course in aggression management on seclusion rates in Switzerland: a multi center study
Graduate Recital: Stefanie Abderhalden, Flute; Patricia Foltz, Piano; March 30, 2010
Kemp Recital HallMarch 30, 2010Tuesday Evening6:00 p.m
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