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1.

Background

Arousal and sleep represent basic domains of behavior, and alterations are of high clinical importance.

Objective/hypothesis

The aim of this study was to further elucidate the neurobiology of insomnia disorder (ID) and the potential for new treatment developments, based on the modulation of cortical activity through the non-invasive brain stimulation technique transcranial direct current stimulation (tDCS). Specifically, we tested the hypotheses that bi-frontal anodal tDCS shortens and cathodal tDCS prolongs total sleep time in patients with ID, compared to sham stimulation. Furthermore, we tested for differences in indices of arousal between ID patients and healthy controls and explored their potential impact on tDCS effects.

Methods

Nineteen ID patients underwent a within-subject repeated-measures sleep laboratory study with adaptation, baseline and three experimental nights. Bifrontal anodal, cathodal and sham tDCS was delivered in a counterbalanced order immediately prior to sleep. Wake EEG was recorded prior to and after tDCS as well as on the following morning. Subsequently, we compared patients with ID to a healthy control group from an earlier dataset.

Results

Against our hypothesis, we did not observe any tDCS effects on sleep continuity or sleep architecture in patients with ID. Further analyses of nights without stimulation demonstrated significantly increased levels of arousal in ID patients compared to healthy controls, as indexed by subjective reports, reduced total sleep time, increased wake after sleep onset and increased high frequency EEG power during wakefulness and NREM sleep. Of note, indices of increased arousal predicted the lack of effect of tDCS in ID patients.

Conclusions

Our study characterizes for the first time differential effects of tDCS on sleep in patients with ID and healthy controls, presumably related to persistent hyperarousal in ID. These findings suggest that adapted tDCS protocols need to be developed to modulate arousal and sleep dependent on baseline arousal levels.  相似文献   
2.
The current study was designed to further clarify the influence of brain morphology, sleep oscillatory activity and age on memory consolidation. Specifically, we hypothesized, that a smaller volume of hippocampus, parahippocampal and medial prefrontal cortex negatively impacts declarative, but not procedural, memory consolidation. Explorative analyses were conducted to demonstrate whether a decrease in slow‐wave activity negatively impacts declarative memory consolidation, and whether these factors mediate age effects on memory consolidation. Thirty‐eight healthy participants underwent an acquisition session in the evening and a retrieval session in the morning after night‐time sleep with polysomnographic monitoring. Declarative memory was assessed with the paired‐associate word list task, while procedural memory was tested using the mirror‐tracing task. All participants underwent high‐resolution magnetic resonance imaging. Participants with smaller hippocampal, parahippocampal and medial prefrontal cortex volumes displayed a reduced overnight declarative, but not procedural memory consolidation. Mediation analyses showed significant age effects on overnight declarative memory consolidation, but no significant mediation effects of brain morphology on this association. Further mediation analyses showed that the effects of age and brain morphology on overnight declarative memory consolidation were not mediated by polysomnographic variables or sleep electroencephalogram spectral power variables. Thus, the results suggest that the association between age, specific brain area volume and overnight memory consolidation is highly relevant, but does not necessarily depend on slow‐wave sleep as previously conceptualized.  相似文献   
3.
JB Ma  SX Yao  H  Li  Q  Pei JF  Yao 《美中国际创伤杂志》2014,(1):1-4,9
In this case, a male patient presented with a clinically and radiographieally unstable slipped capital femoral epiphysis (SCFE) as well as slipped calcaneal epiphysis years. Subsequent thorough at the age of 23 work-up revealed that he had some features of rickets and labo- ratory test demonstrated he had hypophos- phatemia (2.3mg/dl), normocalcemia, normal vi- tamin D metabolite levels, and secondary hy- perparathyroidism.  相似文献   
4.
OBJECTIVES: Unsedated colonoscopy is an uncomfortable procedure for most patients. Discomfort during colonoscopy is largely related to looping of the colonoscope, which displaces the colon from its native configuration and stretches attachments to the mesentery. A novel computer-assisted colonoscope utilizes a fully articulated, computer-controlled insertion tube. On manual insertion of the colonoscope, the position and angle of the scope's tip are encoded into a computer algorithm. As the colonoscope is advanced, the computer directs each successive segment to take the same shape that the tip had at a given insertion depth. The insertion tube thus changes its shape at different insertion depths in a "follow-the-leader" manner. METHODS: This initial clinical trial with this novel colonoscopy system was designed as a prospective, nonrandomized, unblinded, feasibility study. Three physicians of varying levels of experience participated in the study. RESULTS: Eleven consecutive patients (seven men, four women, age range 19-80) meeting inclusion criteria for screening or diagnostic colonoscopy were enrolled in the study. The cecum was reached in 10 consecutive patients (100%). Findings included diverticular disease in two cases and multiple colonic polyps in two cases. Postprocedure assessment at discharge, 48 h, and 30 days revealed no complications or adverse effects. Physician satisfaction and patient acceptance of this new technique were high. CONCLUSIONS: In this limited, first of its kind feasibility study, the computer-assisted colonoscope was shown to perform colonoscopy safely and effectively. The colonoscope's unique design limited loop formation during colonoscopy. Large-scale clinical trials are indicated.  相似文献   
5.
Follow-up after endoscopic snare resection of duodenal adenomas   总被引:2,自引:0,他引:2  
BACKGROUND AND STUDY AIMS: Premalignant duodenal polyps are considered to be rare. Recurrence after local excision is reported to be frequent, so many authors propose radical surgical treatment of these tumors. The aim of this study was to determine the long-term outcome after endoscopic resection of duodenal adenomas. PATIENTS AND METHODS: Between January 1990 and April 2003 we retrospectively evaluated a group of patients who presented with nonampullary duodenal villous tumors but who did not have a polyposis syndrome. RESULTS: Duodenal polyps were diagnosed in 21 patients during routine endoscopy during the study period. Of these, 18 patients (6 men, 12 women; median age 67, range 50 - 81), with a total of 20 duodenal adenomas, were enrolled into the study. The median size +/- SD of the tumors was 27.5 +/- 12 mm (range 8 - 50 mm). Of these 20 tumors, 18 adenomas were tubulovillous, one was tubulous and one was villous. Nineteen polyps were treated by snare excision and one adenoma was treated with argon plasma coagulation alone. Argon plasma coagulation was applied to polyps in six patients after snare excision during this initial treatment phase. The success rate for endoscopic adenoma removal after a 3-month interval was 55 %. After a median follow-up period of 71 months (range 22 - 151 months), 12 patients remained in remission. Local recurrences of the lesion occurred in five patients (25 %) and these were re-treated. None of the patients developed carcinoma during the follow-up period. CONCLUSIONS: Endoscopic snare excision of duodenal adenomas is an effective mode of treatment but an endoscopic surveillance program is mandatory in order to detect and treat recurrence.  相似文献   
6.
目的:间充质干细胞具有强大的增殖能力和多向分化潜能,文章对其主要的来源途径予以综述。资料来源:应用计算机检索Medline1991-01/2006-01期间的相关文章,检索词为“mesenchyma stem cells,origin,research progress”,并限定文章语言种类为English。同时计算机检索中国期刊全文数据库1998-01/2006-10期间的相关文章,检索词为“间充质干细胞,来源,研究进展”,并限定文章语言种类为中文。资料选择:对资料进行初审,并查看每篇文献后的引文。纳入标准:①间充质干细胞的起源。②间充质干细胞研究进展、干细胞的分离及鉴定。排除标准:重复研究、个案报告或Meta分析类文章。资料提炼:共收集到96篇相关文献,40篇文献符合纳入标准,排除的56篇文献为内容陈旧或重复。符合纳入标准的40篇文献中,分别涉及骨髓、肌肉、脐血、胎盘、外周血、脂肪组织、血管及其他来源的间充质干细胞。资料综合:间充质干细胞是属于中胚层的一类多能干细胞,具有强大的增殖能力和多向分化潜能,动物模型试验和临床应用研究也取得了一定的效果。间充质干细胞来源广泛,易于获得,临床上为神经损伤及其他系统的损伤修复提供了更为广泛的途径。结论:间充质干细胞主要来源于骨髓、肌肉、脐血、外周血、胎盘等组织,具有广阔的应用前景。  相似文献   
7.
颈动脉血管重构特征在自发性高血压大鼠体内的表现   总被引:2,自引:0,他引:2  
目的:血管重构是高血压的重要病理变化,是高血压导致器官损害的结构基础。实验观察自发性高血压大鼠颈动脉中层组织学的相关变化,以验证血管重构的特点。方法:实验于2006-06/2007-03在福建医科大学附属协和医院心血管内科实验室完成。①实验材料及分组:12周龄雄性自发性高血压大鼠10只,同性别周龄的WKY大鼠10只为对照,喂养18周后终止实验。②实验过程及评估:开始及每2周测鼠尾收缩压。实验结束后,麻醉后取颈动脉,行苏木精-伊红、苦味酸-天狼星红、弹力纤维和胶原纤维的双重染色(P/VB法),利用计算机辅助成像系统测算颈动脉中膜厚度、腔径、血管中膜厚/腔径、中膜横截面积、中膜细胞平均核面积及中膜的胶原面积百分比、弹性纤维面积百分比、弹性纤维面积与胶原面积的比值。SP免疫组织化学染色检测α-平滑肌肌动蛋白、增殖细胞核抗原、纤维粘连蛋白、层粘连蛋白等抗原在颈动脉壁的表达,并计算颈动脉中膜细胞增殖指数;以原位末端标记法标记血管壁的凋亡细胞,计算颈动脉中膜细胞凋亡指数。结果:20只大鼠全部进入结果分析。①自发性高血压大鼠实验开始和结束前的收缩压均>150mmHg,高于WKY大鼠(P<0.01)。②自发性高血压大鼠颈动脉中膜厚度、腔径、中膜厚度/腔径、中膜横截面积、中膜胶原面积百分比均高于WKY大鼠(P<0.01),而中膜弹性纤维面积百分比、弹性纤维面积与胶原面积比值均低于WKY大鼠(P<0.01)。③α-平滑肌肌动蛋白在两组大鼠颈动脉中膜均可表达,提示中膜细胞为血管平滑肌细胞。④自发性高血压大鼠中膜血管平滑肌细胞平均核面积大于WKY大鼠(P<0.01),中膜细胞增殖指数与WKY大鼠差异无显著性(P>0.05),中膜细胞凋亡指数显著低于WKY大鼠(P<0.01)。⑤自发性高血压大鼠颈动脉中膜纤维粘连蛋白、层粘连蛋白的光密度值(IA值)及染色阳性面积百分比高于WKY大鼠(P<0.01)。⑥颈动脉中膜血管平滑肌细胞凋亡指数与中膜横截面积呈显著负相关(r=-0.872,P<0.01);纤维连接蛋白表达的吸光度值与中膜横截面积呈显著正相关(r=0.954,P<0.01)。结论:自发性高血压大鼠颈动脉存在明显的重构,其特点为中膜肥厚、平滑肌细胞肥大、凋亡减少及胶原、纤维粘连蛋白、层粘连蛋白的过度沉积。  相似文献   
8.
Mood disorders are amongst the most prevalent and severe disorders worldwide, with a tendency to be recurrent and disabling. Although multiple mechanisms have been hypothesized to be involved in their pathogenesis, just a few integrative theoretical frameworks have been proposed and have yet to integrate comprehensively all available findings. As such, a comprehensive framework would be quite useful from a clinical and therapeutic point of view in order to identify elements to evaluate and target in the clinical practice. Because conditions of sleep loss, which include reduced sleep duration and insomnia, are constant alterations in mood disorders, the aim of this paper was to review the literature on their potential role in the pathogenesis of mood disorders and to propose a novel theoretical model. According to this hypothesis, sleep should be considered the main regulator of several systems and processes whose dysregulation is involved in the pathogenesis of mood disorders. The model may help explain why sleep disturbances are so strikingly linked to mood disorders, and underscores the need to evaluate, assess and target sleep disturbances in clinical practice, as a priority, in order to prevent and treat mood disorders.  相似文献   
9.
Cognitive-behavioral models of obsessive–compulsive disorder (OCD) propose that erroneous beliefs about the importance and need to control thoughts lead individuals with OCD to overuse maladaptive thought control strategies such as worry and self-punishment. These strategies are thought to backfire, leading to obsessional symptoms. Whereas previous studies have examined predictors of the use of thought control strategies, none have investigated these strategies as mediators in the prediction of OCD symptom severity. An additional gap in the literature is the lack of attention to OCD symptom dimensions. The present study, therefore, extended existing work by examining thought control strategies as mediators of the relationship between obsessive beliefs and OCD symptom dimensions in a treatment-seeking sample of 102 adults with OCD. In line with our hypotheses, the use of punishment (but not worry) as a thought control tactic mediated the relationship between dysfunctional beliefs about the importance/control of thoughts and unacceptable obsessions. These findings are discussed in terms of the conceptualization and treatment of OCD. Future research should investigate the extent to which these various thought control strategies may be helpful versus harmful using idiographic measures of thought control and employing experimental designs.  相似文献   
10.
Obsessive–compulsive disorder (OCD) is the 10th leading cause of disability among health conditions; yet, relatively little research has focused on quality of life (QOL) and functional impairment in OCD. The present study extended existing work by examining correlates and predictors of QOL and functional impairment in 96 treatment-seeking OCD patients (in intensive outpatient and residential settings). In a model including OCD symptoms and related phenomena, and symptoms of depression and anxiety, two main findings emerged: (a) depressive symptoms predicted both QOL and functional impairment, and (b) contamination symptoms predicted functional impairment. These findings are discussed in terms of the implications for studying QOL and functional impairment in OCD. Future research should investigate the factors that predict changes in QOL and functional impairment following treatment.  相似文献   
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