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1.
The celiac disease (CD) is an inflammatory condition characterized by injury to the lining of the small-intestine on exposure to the gluten of wheat, barley and rye. The involvement of gluten in the CD syndrome has been studied in detail in bread wheat, where a set of “toxic” and “immunogenic” peptides has been defined. For wheat diploid species, information on CD epitopes is poor. In the present paper, we have adopted a genomic approach in order to understand the potential CD danger represented by storage proteins in diploid wheat and sequenced a sufficiently large number of cDNA clones related to storage protein genes of Triticum monococcum. Four bona fide toxic peptides and 13 immunogenic peptides were found. All the classes of storage proteins were shown to contain harmful sequences. The major conclusion is that einkorn has the full potential to induce the CD syndrome, as already evident for polyploid wheats. In addition, a complete overview of the storage protein gene arsenal in T. monococcum is provided, including a full-length HMW x-type sequence and two partial HMW y-type sequences. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
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Loss of the survival motor neuron gene (SMN1) is responsible for spinal muscular atrophy (SMA), the most common inherited cause of infant mortality. Even though the SMA phenotype is traditionally considered as related to spinal motor neuron loss, it remains debated whether the specific targeting of motor neurons could represent the best therapeutic option for the disease. We here investigated, using stereological quantification methods, the spinal cord and cerebral motor cortex of ∆7 SMA mice during development, to verify extent and selectivity of motor neuron loss. We found progressive post-natal loss of spinal motor neurons, already at pre-symptomatic stages, and a higher vulnerability of motor neurons innervating proximal and axial muscles. Larger motor neurons decreased in the course of disease, either for selective loss or specific developmental impairment. We also found a selective reduction of layer V pyramidal neurons associated with layer V gliosis in the cerebral motor cortex. Our data indicate that in the ∆7 SMA model SMN loss is critical for the spinal cord, particularly for specific motor neuron pools. Neuronal loss, however, is not selective for lower motor neurons. These data further suggest that SMA pathogenesis is likely more complex than previously anticipated. The better knowledge of SMA models might be instrumental in shaping better therapeutic options for affected patients.  相似文献   
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Is progesterone a pre-hormone in the CNS?   总被引:3,自引:0,他引:3  
In this paper, experimental evidences have been presented indicating that progesterone per se appears to be a powerful modulatory steroid of presynaptic striatal dopaminergic terminals of the central nervous system of the rat. This effect of the progesterone signal is concentration as well as infusion mode dependent. Low pulsatile doses of the steroid positively modulate the mechanism by which dopamine terminals respond to amphetamine stimulation and increase tissue dopamine concentration. Whereas, continuous and/or high doses of this steroid negatively modulate the response of the dopamine terminals to amphetamine stimulation and decreases tissue dopamine concentration. This effects occurs through a membrane mediated mechanism either upon the dopamine neuron directly and/or upon an interneuron. Pregnanolone a 5- beta-3 beta-metabolite of progesterone known to activate the hypothalamic LHRH neural apparatus at the level of the hypothalamus of ovariectomized estrogen primed rats in both in vitro as well as in vivo preparations was completely ineffective at the level of the corpus striatum of similar animal preparations. Therefore, it is reasonable to assume that site specific mechanisms exist within the central nervous system which may control differentially the final action of progesterone. In the hypothalamus, pregnanolone appears to be the final signal for its action on the LHRH neural apparatus, whereas in the corpus striatum, the steroid per se, and dependent on the modality and/or the strength of the signal can either directly or indirectly up-regulate (stimulatory component) or down-regulate (inhibitory component) the activity of striatal dopaminergic terminals.  相似文献   
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