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Asthma is a common respiratory disorder characterized by recurrent episodes of coughing, wheezing and breathlessness. Although environmental factors such as allergen exposure are risk factors in the development of asthma, both twin and family studies point to a strong genetic component. To date, linkage studies have identified more than a dozen genomic regions linked to asthma. In this study, we performed a genome-wide scan on 460 Caucasian families and identified a locus on chromosome 20p13 that was linked to asthma (log(10) of the likelihood ratio (LOD), 2.94) and bronchial hyperresponsiveness (LOD, 3.93). A survey of 135 polymorphisms in 23 genes identified the ADAM33 gene as being significantly associated with asthma using case-control, transmission disequilibrium and haplotype analyses (P = 0.04 0.000003). ADAM proteins are membrane-anchored metalloproteases with diverse functions, which include the shedding of cell-surface proteins such as cytokines and cytokine receptors. The identification and characterization of ADAM33, a putative asthma susceptibility gene identified by positional cloning in an outbred population, should provide insights into the pathogenesis and natural history of this common disease.  相似文献   
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选用C57BL/6小鼠,随机分为两组.实验组小鼠通过匹罗卡品(PILO)腹腔注射,诱发癫痫持续状态(SE);对照组给予等容量生理盐水.SE后4周测试小鼠听力,SE后6~7周播放莫扎特K.448,探究莫扎特K.448对颞叶癫痫模型鼠自发发作期高频脑电(EEG)活性的影响.数据显示,PILO注射未明显影响小鼠的听力,给予莫扎特K.448使对照组与SE模型鼠在55~145 Hz区间的功率谱显著升高.结果表明,短时期给予莫扎特K.448音乐治疗能导致小鼠EEG高频活性增强.  相似文献   
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Choanoflagellates are the closest known relatives of metazoans. To discover potential molecular mechanisms underlying the evolution of metazoan multicellularity, we sequenced and analysed the genome of the unicellular choanoflagellate Monosiga brevicollis. The genome contains approximately 9,200 intron-rich genes, including a number that encode cell adhesion and signalling protein domains that are otherwise restricted to metazoans. Here we show that the physical linkages among protein domains often differ between M. brevicollis and metazoans, suggesting that abundant domain shuffling followed the separation of the choanoflagellate and metazoan lineages. The completion of the M. brevicollis genome allows us to reconstruct with increasing resolution the genomic changes that accompanied the origin of metazoans.  相似文献   
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Retinoblastoma is an aggressive childhood cancer of the developing retina that is initiated by the biallelic loss of RB1. Tumours progress very quickly following RB1 inactivation but the underlying mechanism is not known. Here we show that the retinoblastoma genome is stable, but that multiple cancer pathways can be epigenetically deregulated. To identify the mutations that cooperate with RB1 loss, we performed whole-genome sequencing of retinoblastomas. The overall mutational rate was very low; RB1 was the only known cancer gene mutated. We then evaluated the role of RB1 in genome stability and considered non-genetic mechanisms of cancer pathway deregulation. For example, the proto-oncogene SYK is upregulated in retinoblastoma and is required for tumour cell survival. Targeting SYK with a small-molecule inhibitor induced retinoblastoma tumour cell death in vitro and in vivo. Thus, retinoblastomas may develop quickly as a result of the epigenetic deregulation of key cancer pathways as a direct or indirect result of RB1 loss.  相似文献   
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Substitution of arginine for glutamine in the 4-position of a vasopressin V1 antagonist has been reported to turn it into an agonist. We resynthesized this 4-arginine analog and synthesized additional cyclic and linear vasopressin antagonists containing a 4-arginine. The presence of a 4-arginine in the resynthesized and new analogs had relatively minor effects on their antivasopressin V1 and V2 antagonistic potencies.  相似文献   
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