功能性消化不良患者事件相关电位P300的变化和意义

目的:探讨事件相关电位P300在功能性消化不良患者中的变化和意义。方法:对27例FD患者和27例健康对照者应用汉密尔顿抑郁焦虑量表、FD主要症状评分表评分和脑电生理仪测定事件相关电位P300,对FD组经四周心理介入(小剂量阿米替林和心理疏导)治疗后,应用上述方法再次评测。结果:FD患者事件相关电位P300较健康对照者P3潜伏期延长(P<0.05)、P3波幅降低(P<0.05),FD患者抑郁焦虑量表评分和主要临床症状评分较健康对照组均高并有差异(P<0.05),FD患者焦虑抑郁评分与P3潜伏期、临床症状评分呈正相关(P<0.01)。FD患者焦虑抑郁评分与P3波幅呈负相关(P<0.01)。心理介入治疗后事件相关电位P300、抑郁焦虑量表评分和主要临床症状评分均明显改善。结论:伴有焦虑抑郁FD患者有认知功能障碍,认知功能可能介入FD发病机制。     

注意缺陷多动障碍儿童的事件相关脑电位研究

【目的】探索注意缺陷多动障碍儿童(attention deficit hyperactivity disorder,ADHD)的事件相关脑电位P300的特点。【方法】符合DSM-Ⅳ诊断标准的ADHD患儿组40例,正常对照组22例。对所有对象进行儿童韦氏量表、P300测试。【结果】P300:ADHD组P300各潜伏期与正常对照组相比,靶P2、N2、P3潜伏期延长,差异有显著性(P<0.05),P3波幅下降其差异有显著性(P<0.05)。②P300潜伏期与C-WISC的总智商、操作智商、语言理解智商因子及记忆/注意智商因子具有相关性(P<0.05)。【结论】事件相关脑电位P300可作为临床评价ADHD患儿认知功能的脑电生理指标。     

精神分裂症患者攻击行为与事件相关电位P300的相关性研究

目的探讨P300作为精神分裂症患者攻击行为的脑电生理学预测因子的可行性。方法采用病例对照研究方法，收集30对有或无攻击行为的精神分裂症男性患者。对两组患者的人口学资料、简明精神病量表（BPRs）各因子分、修改版外显攻击行为量表（MOAS）总分和各因子分、冲动量表（BIS-11）总分、敌意量表（BDHI）总分和各因子分、P300潜伏期及P300振幅进行比较和分析。结果①两组在婚姻状况、文化程度、职业、精神分裂症首次发病年龄、病期、治疗情况、自杀史、早年不良家庭环境方面的分布差异均无统计学意义（P〉0．05）。②研究组MOAS总分、MOAS自身及对他人攻击因子分、BIS-11总分、BDHI总分、BDHI躯体攻击因子分及易激惹因子分均高于对照组，差异均有统计学意义（P〈0．01）。③研究组中央顶部（Cz）事件相关电位P300振幅比对照组降低，P300潜伏期比对照组延长，差异有统计学意义（P〉0．05）。结论有攻击行为的男性精神分裂症患者比非攻击对照组事件相关电位P300（CZ）潜伏期延长，振幅降低，提示男性精神分裂症攻击个体可能存在更严重的认知功能障碍。     

Mogrosides extract from Siraitia grosvenori scavenges free radicals in vitro and lowers oxidative stress,serum glucose,and lipid levels in alloxan-induced diabetic mice

This study evaluated the supplementation of a mogrosides extract (MG) from fruits of Siraitia grosvenori on reducing oxidative stress, hyperglycemia, and hyperlipidemia in alloxan-induced diabetic mice. The oxygen free radical scavenging activity of MG was also assessed in vitro. After induction of diabetes, a significant increase in the levels of serum glucose, total cholesterol (TC), triacylglycerol (TG), and hepatic malondialdehyde (MDA) as well as a reduction in the level of hepatic high-density lipoprotein cholesterol (HDL-C) associated with diminution of the corresponding antioxidant enzymes, such as glutathione peroxidase (GSH-Px) and superoxide dismutase, were observed in all diabetic mice. Treatment of diabetic mice with MG (100, 300, and 500 mg/kg ) for 4 weeks significantly decreased serum glucose, TC, TG, and hepatic MDA levels (P < .05), whereas it increased serum HDL-C level and reactivated the hepatic antioxidant enzymes (P < .05) in alloxan-induced diabetic mice (P < .05). The hypoglycemic, hypolipidemic, and antioxidative activities of MG (100 mg/kg treatment) were all higher compared with all other diabetic groups and were similar to that observed for XiaoKeWan-pill (894 mg/kg; Guangzhou Zhongyi Pharmaceutical Co., Ltd., Guangzhou, China), a Chinese traditional antidiabetic drug. Antioxidant capacity evaluated in vitro showed that MG and mogroside V, which was the main component of MG, possessed strong oxygen free radical scavenging activities. These results demonstrate that the extract may have capacity to inhibiting hyperglycemia induced by diabetes, and the data suggest that administration of the extract may be helpful in the prevention of diabetic complications associated with oxidative stress and hyperlipidemia. We conclude that the extract should be evaluated as a candidate for future studies on diabetes mellitus.     

Hyperventilation in head injury: a review

The aim of this review was to consider the effects of induced hypocapnia both on systemic physiology and on the physiology of the intracranial system. Hyperventilation lowers intracranial pressure (ICP) by the induction of cerebral vasoconstriction with a subsequent decrease in cerebral blood volume. The downside of hyperventilation, however, is that cerebral vasoconstriction may decrease cerebral blood flow to ischemic levels. Considering the risk-benefit relation, it would appear to be clear that hyperventilation should only be considered in patients with raised ICP, in a tailored way and under specific monitoring. Controversy exists, for instance, on specific indications, timing, depth of hypocapnia, and duration. This review has specific reference to traumatic brain injury, and is based on an extensive evaluation of the literature and on expert opinion.     

Quadriceps weakness is related to exercise capacity in idiopathic pulmonary fibrosis

STUDY OBJECTIVE: In COPD, it has been shown that peripheral muscle dysfunction is a factor determining exercise intolerance. We examined the hypothesis that exercise capacity of patients with idiopathic pulmonary fibrosis (IPF) is, at least in part, determined by peripheral muscle dysfunction. METHODS: Maximum oxygen uptake (V(O2)max) was evaluated in 41 consecutive patients with IPF, along with potential determinants of exercise capacity, both in the lungs and in the peripheral muscles. RESULTS: Patients had reduced V(O2)max (893 +/- 314 mL, 46.0% predicted) and reduced quadriceps force (QF) [65% predicted]. Significant correlates of V(O2)max reduction were vital capacity (VC) [r = 0.79], total lung capacity (r = 0.64), diffusion capacity (r = 0.64), QF (r = 0.62), maximum expiratory pressure (r = 0.48), and Pa(O2) at rest (r = 0.33). In stepwise multiple regression analysis, VC and QF were independent predictors of V(O2)max. Furthermore, in subgroup analysis, QF was a significant contributing factor for V(O2)max in patients who discontinued exercise because of dyspnea and/or leg fatigue. CONCLUSIONS: We conclude that QF is a predictor of exercise capacity in IPF. Measures that improve muscle function might improve exercise tolerance.     

Expectancy effects on omission evoked potentials in musicians and non-musicians

Abstract An expanded omitted stimulus paradigm was investigated to determine whether expectancy would modulate the amplitude of the omission evoked potentials (OEPs). In addition, we examined the effects of musical expertise on OEPs. Trials started with 3-7 beats randomly and contained 5 omitted beats. Three types of trials (n = 90) were presented with 1, 2, or 3 beats occurring between omissions. A tap response at the end of each trial was used to determine timing accuracy. Clear OEPs were observed over midline sites. We found main omission effects with respect to an N150 and a P400 OEPs component, such that peak amplitudes diminished whenever the occurrence of an omitted stimulus could be expected. In addition, an N600 OEPs component emerged in response to expectedly omitted stimuli toward the end of each trial within the group of musicians. Thus, musical training seems to lead to more efficient and more refined processing of auditory temporal patterns.     

Reduced response-inhibition in obsessive-compulsive disorder measured with topographic evoked potential mapping

Recent neuroimaging studies have suggested that a hyperactivity of the frontal-striate neuronal circuits, including the orbitofrontal cortex and the basal ganglia, mediates the symptomatology of obsessive–compulsive disorder (OCD). However, there is also some evidence that the superior frontal cortex is less activated in OCD, and this local hypoactivity has been shown to be negatively associated with the symptomatology. As the superior frontal cortex is believed to be involved in inhibitory control, this study investigated the brain electrical activity during response inhibition in OCD. Twelve patients with OCD and 12 healthy controls performed a cued Go–NoGo task (continuous performance test), while event-related potentials were registered with 21 electrodes. Patients reacted significantly faster than controls, but did not differ from controls regarding the error rate. As a main result, we found a reduced frontal activity during the NoGo condition in OCD, which was condensed in a reduced anteriorisation of the brain electrical field. We suggest that this inhibitory deficit in OCD has a major contribution to the pathophysiology of OCD, which is underscored by the fact that the anteriorisation during the NoGo condition (NGA) was negatively correlated with the symptomatology as measured by the Yale-Brown Obsessive-Compulsive Scale.     

老年2型糖尿病患者听觉事件相关电位P300的改变

目的探讨2型糖尿病（type2 diabetes mellitus，DM）及其相关因素对老年患者认知功能的影响。方法老年2型糖尿病患者72例，平均（67．8±6．2）岁，经cT检查分为单纯糖尿病组（单纯DM组）38例，平均（67．3±5．8）岁，糖尿病合并缺血性脑损害组（DM并脑缺血组）34例，平均（68．3±6．7）岁，行听觉事件相关电位（P300）及简易智能量表（MMSE）检测，并与正常对照组31例比较；分析性别、年龄、受教育年限、糖尿病病程、糖化血红蛋白（glycosylated hemoglobin，GHB）、缺血性脑损害等因素对听觉事件相关电位（P300）的影响。结果MMSE评分单纯DM组与正常对照组比较差异无统计学意义（P〉0．05）；DM并脑缺血组较正常对照组降低（P〈0．01）。老年2型糖尿病各组P300的N2、P3潜伏期（Lat）较正常对照组延长（P〈0．01），P3波幅（Amp）较对照组降低（P〈0．01）；DM并脑缺血组N2、P3潜伏期较单纯DM组延长（P〈0．01），波幅差异无统计学意义（P〉0．05）。多元线性回归分析显示，老年2型糖尿病患者P3潜伏期与患者年龄、病程、糖化血红蛋白（GHB）及合并缺血性脑损害正相关，P3波幅与患者年龄、病程、GHB负相关，N2潜伏期与患者年龄、病程、合并缺血性脑损害正相关。结论老年2型糖尿病患者有认知功能损害，其中糖尿病病程、GHB及合并缺血性脑损害是认知功能损害的主要影响因素，P300检测可作为老年糖尿病认知损害早期诊断和动态监测的敏感指标。     

P300 and Slow Wave in a Message Consisting of Two Events

This study is concerned with P300 and Slow Wave in an experimental paradigm in which information is transmitted by a combination of two successive events (a ‘message’). Each event delivered essential information for understanding the message, but the meaning of the message could not be determined until occurrence of the second event. The amount of information in each event was varied by varying its perceptual difficulty. Increasing perceptual difficulty causes an information loss, termed equivocation. A positive Slow Wave was elicited by both events. Slow wave was clearly increased in amplitude by equivocation in the eliciting event, and less clearly increased in amplitude by equivocation in the other event. The first event elicited a small P290 component. It could not be determined whether this component corresponded to P300. The second event elicited a large P300. This component was much reduced in amplitude by equivocation in the second event, but was only moderately reduced in amplitude by equivocation in the first event.