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A 67‐year‐old male presented with a left ventricular ejection fraction of 21% and an atrial septal defect (ASD), the closure of which carries a risk of worsening the patients' clinical situation. The ASD contributed significantly to heart failure according to NYHA class III to IV, on the other hand. Preconditioning, echocardiographic testing, and test closure were carried out in order to minimize the risk and to finally close the defect successfully in behoof of the patient. © 2012 Wiley Periodicals, Inc.  相似文献   
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Spinocerebellar ataxia type 7 (SCA7) is an autosomal‐dominant neurodegenerative disorder characterized by progressive ataxia and retinal dystrophy. It is caused by a CAG trinucleotide expansion in the ataxin7 gene. Anatomical studies have shown severe cerebellar degeneration and region‐specific neocortical atrophy in SCA7 patients. However, the impact of the neurodegeneration on the functional integration of the remaining tissue is still unknown. The aim of this study was to examine functional connectivity abnormalities in areas with significant gray matter atrophy in SCA7 patients and their relationship with number of CAG repeats. Using a combination of voxel‐based morphometry and resting‐state fMRI, we studied 26 genetically confirmed SCA7 patients and aged‐matched healthy controls. In SCA7 patients we found reduced functional interaction between the cerebellum and the middle and superior frontal gyri, disrupted functional connectivity between the visual and motor cortices, and increased functional coordination between atrophied areas of the cerebellum and a range of visual cortical areas compared with healthy controls. The degree of mutation expansion showed a negative effect on both the functional interaction between the right anterior cerebellum and the left superior frontal gyrus and the connectivity between the right anterior cerebellum and left parahippocampal gyrus. We found abnormal functional connectivity patterns, including both hypo‐ and hyperconnectivity, compared with controls. These abnormal patterns show reasonable association with the severity of gene mutation. Our findings suggest that aberrant changes are prevalent in both motor and visual systems, adding significantly to our understanding of the pathophysiology of SCA7. © 2013 International Parkinson and Movement Disorder Society  相似文献   
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Synchronization of circadian rhythms to the 24‐h light/dark (L/D) cycle is associated with daily rearrangements of the neuronal‐glial network of the suprachiasmatic nucleus of the hypothalamus (SCN), the central master clock orchestrating biological functions in mammals. These anatomical plastic events involve neurons synthesizing vasoactive intestinal peptide (VIP), known as major integrators of photic signals in the retinorecipient region of the SCN. Using an analog‐sensitive kinase allele murine model (TrkBF616A), we presently show that the pharmacological blockade of the tropomyosin‐related kinase receptor type B (TrkB), the high‐affinity receptor of brain‐derived neurotrophic factor (BDNF), abolished day/night changes in the dendrite enwrapping of VIP neurons by astrocytic processes (glial coverage), used as an index of SCN plasticity on electron‐microscopic sections. Therefore, the BDNF/TrkB signaling pathway exerts a permissive role on the ultrastructural rearrangements that occur in SCN under L/D alternance, an action that could be a critical determinant of the well‐established role played by BDNF in the photic regulation of the SCN. In contrast, the extent of glial coverage of non‐VIP neighboring dendrites was not different at daytime and nighttime in TrkBF616A mice submitted to TrkB inactivation or not receiving any pharmacological treatment. These data not only show that BDNF regulates SCN structural plasticity across the 24‐h cycle but also reinforce the view that the daily changes in SCN architecture subserve the light synchronization process.  相似文献   
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Brain responses evoked by transcranial magnetic stimulation (TMS) in task‐free experimental contexts are known to depend on psychophysiological states such as sleep, vegetative state and caffeine‐induced arousal. Much less is known about how TMS‐evoked responses depend on task‐irrelevant steady perceptual input. Here, we examined ongoing alpha activity and the mean amplitude of EEG potentials in response to occipitally applied TMS as a function of task‐irrelevant visual backgrounds. Responses to TMS were robustly modulated by photographs of natural scenes and man‐made environments. These effects began as early as during the N100 and continued for several hundred milliseconds after the stimulation. There was also a more general effect of background along with other stimuli, such as blank backgrounds, sinusoidal gratings and moving dot‐patterns. This effect was observable from ongoing alpha activity as well. Based on these results we conclude that different types of steady perceptual input modulate visual cortex reactivity and/or connectivity and it is possible to measure these modulations by combining TMS with electroencephalography.  相似文献   
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目的 采用静息态功能连接(FC)与低频振幅(ALFF)技术,结合注意网络测试(ANT),探讨高温下人脑静息态神经活动变化及意义。方法 令18名被试按随机交叉顺序在高温(50℃)与常温(25℃)下暴露1 h后,采集fMRI数据,扫描结束后进行ANT测试。采用FC与ALFF分析fMRI数据,得到全脑FC网络与ALFF图,分别对其进行配对t检验,并对额-顶区ALFF与FC变化与注意网络效应值进行相关分析。结果 额眶区与颞叶、顶叶和枕叶等脑区连接显著降低,颞叶与额眶区、对侧颞叶、顶叶和枕叶连接显著降低,而脑岛、基底核区和丘脑以及额顶躯体感觉运动区等连接显著升高。前额叶背外侧、额眶区、颞叶等区域神经活动降低,而右侧躯体感觉运动区、丘脑及周围神经核团神经活动大幅度增强。执行控制效应降低与ALFF及FC改变显著相关。结论 高温下人脑静息态成像模式的变化可能反映了高温下认知功能改变的神经学基础与中枢神经系统自主调节与行为调节机制。  相似文献   
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