海马神经元兴奋性毒性模型的建立及其意义

目的探讨不同浓度谷氨酸对海马神经元的损伤作用,流式细胞仪在建立理想的兴奋性毒性模型中的应用。方法在体外原代培养10d的海马神经元中分别加入不同浓度的谷氨酸(100、200、400、600、800μmol/L),24h后相差显微镜下观察细胞形态变化,用MTT法检测存活率和流式细胞仪检测凋亡率以评定谷氨酸对海马神经元的损伤程度。结果不同浓度的谷氨酸组与对照组的细胞存活率差异有显著性(P<0.01),并呈浓度依赖性,随着谷氨酸浓度的升高,神经元的存活率降低;谷氨酸终浓度(100、200、400μmol/L)组的细胞凋亡率与对照组比较差异有显著性(P<0.01);600和800μmol/L谷氨酸组的细胞凋亡率与对照组比较差异无显著性(P>0.05),但细胞凋亡率随着谷氨酸浓度的增加而降低。结论过高浓度的谷氨酸导致细胞急性坏死而非迟发性凋亡,运用流式细胞仪检测体外培养海马神经元凋亡率是一种特异性高的检测方法,值得推广。     

重组Bcl-2腺病毒对损伤运动神经元的保护作用

目的:观察携带Bcl-2基因的重组腺病毒(Ad/s-Bcl-2)对损伤运动神经元的保护作用.方法:采用培养脊髓运动神经元的谷氨酸损伤模型,评价重组Bcl-2腺病毒对损伤运动神经元的影响.指标是Bcl-2原位杂交和Bcl-2免疫组化染色、TUNEL阳性神经元计数、运动神经元[Ga2+]i的检测以及台盼蓝拒染法检测培养神经元存活.结果:①Ad/s-Bcl-2可转染原代培养的脊髓运动神经元并使其过表达Bcl-2.②过表达Bcl-2可延长培养神经元的生存时间.③过表达Bcl-2可显著减少谷氨酸诱导的原代培养脊髓运动神经元的凋亡,并显著降低谷氨酸诱导的神经元[ca2+]i的增高.结论:腺病毒中介Bcl-2基因过表达对神经毒性损伤的运动神经元具有保护作用.     

谷胱甘肽与N-乙酰半胱氨酸对谷氨酸诱导海马神经元损伤的影响

目的观察还原型谷胱甘肽(reducedglutathione,GSH)与N-乙酰半胱氨酸(N-Acetylcysteine,N-NAC)对不同浓度谷氨酸(glutamate,Glu)诱导的海马神经元损害的影响。方法选用新生Wistar大鼠原代培养海马神经元谷氨酸细胞毒性模型,采用台盼蓝活细胞拒染及TUNEL细胞凋亡原位检测等方法比较GSH与NAC对100μmol/L及500μmol/LGlu细胞毒性损伤的影响,并与MK-801比较。结果GSH与NAC能够降低100μmol/LGlu作用下神经元死亡率与凋亡率,NAC组细胞存活率高于同条件下GSH组,其中1mmol/LNAC组神经元存活率达到90.4%±5.2%,与10μmol/LMK-801组相比,差异无统计学意义;在500μmol/LGlu作用下,GSH与NAC则不能增加神经元的存活率,但1mmol/LNAC抗500μmol/LGlu诱导调亡的作用与MK-801相比无明显差异。结论GSH及NAC对轻度Glu细胞毒性神经损伤有保护作用。     

重组腺病毒载体转导的脑源性神经生长因子在大鼠体外培养海马神经元谷氨酸损伤模型中的保护作用

近年来研究表明,脑缺血缺氧损伤机制与兴奋性氨基酸兴奋毒性、钙超载和细胞凋亡等有关。谷氨酸具有毒性损伤作用,但其是否能够引起细胞凋亡尚不确定。大量文献报道,在细胞培养液中加入谷氨酸可模拟体内兴奋性氨基酸损伤状态,但这种损伤与细胞凋亡的关系尚未完全明了。脑源性神经生长因子(BDNF)是神经营养因子之一,这类因子可促进神经元分化生长,对应激状态也有保护作用,但机制尚不完全明了。我们利用体外培养海马神经元观察谷氨酸损伤作用及其与凋亡的关系;以腺病毒为载体转导BDNF(Ad BDNF)观察BDNF蛋白表达;观察Ad BDNF对正常生长…     

刺五加皂甙对谷氨酸毒性神经元凋亡的保护作用

目的观察神经元在谷氨酸毒性损伤时一氧化氮(NO)的动态变化及其与凋亡的关系,探讨刺五加皂甙(ASS)的有效保护浓度。方法采用谷氨酸(Glu)诱导的皮质神经元凋亡模型。随机分成Glu组、正常对照组及ASS3组;用流式细胞仪检测神经元凋亡率,用硝酸还原酶法测定细胞培养上清液中NO的含量,用MTT法测定神经元存活率并在电镜下观察细胞形态学变化。结果(1)Glu呈剂量和时间依赖性增加神经元培养液中NO含量,ASS能不同程度地减少NO含量;(2)与Glu共培养的神经元,其存活率呈剂量和时间依赖性下降,ASS能增加神经元存活率;(3)经Glu处理的神经元发生凋亡,细胞超微结构呈现凋亡样改变,其凋亡率与正常对照组比较有显著性差异(P<0.01)。ASS能减少Glu毒性神经元凋亡。结论NO介导了Glu毒性神经元凋亡,ASS可能通过抑制NO的释放及其神经毒性作用,拮抗Glu引起的神经元凋亡。     

重组Bcl—2腺病毒对损伤运动神经元的保护作用

目的：观察携带Bcl-2基因的重组腺病毒（Ad/s-Bcl-2）对损伤运动神经元的保护作用，方法：采用培养脊髓运动神经元的谷氨酸损伤模型，评价重组Bcl-2腺病毒对损伤运动神经元的影响。指标是Bcl-2原位杂交和Bcl-2免疫组化染色，TUNEL阳性神经元计数，运动神经元[Ca^2 ]i的检测以及台盼蓝拒染法检测培养神经元存在。结果：（1）Ad/s-Bcl-2可转染原代培养的脊髓运动神经元并使其过表达Bcl-2。2）过表达Bcl-2可延长培养神经元的生存时间。（3）过表达Bcl-2可显著减少谷氨酸诱导的原代培养脊髓运动神经元的凋亡，并显著降低谷氨酸诱导的神经元[Ca^2 ]i的增高，结论：腺病毒中介Bcl-2基因表达对神经毒性损伤的运动神经元具有保护作用。     

鼠骨髓间充质干细胞对神经元凋亡的影响

目的探讨体外培养鼠骨髓间充质干细胞对谷氨酸诱导大脑皮质神经元凋亡的影响。方法分离、培养、传代Wistar大鼠骨髓间充质干细胞，细胞融合达90％时更换培养基，继续培养24h，收集细胞培养液即为骨髓间充质干细胞条件培养基；培养新生Wistar大鼠大脑皮质神经元，第8d随机分为对照组、谷氨酸损伤组和骨髓间充质干细胞条件培养基处理组。采用台盼蓝染色计算神经元存活率，同时用流式细胞仪和透射电镜技术检测各组神经元凋亡情况。结果谷氨酸（0．8mmol／L）可诱导细胞凋亡，骨髓间充质干细胞条件培养基处理组较谷氨酸损伤组细胞成活率明显升高（P〈0．001）；流式细胞仪检测见骨髓间充质干细胞条件培养基处理组细胞凋亡率明显降低（P〈0．001）；而电镜检测发现对照组无明显的凋亡细胞，谷氦酸组有典型凋亡神经元，骨髓间充质干细胞条件培养基处理组凋亡细胞数明显减少。结论骨髓间充质干细胞条件培养基对谷氨酸神经元毒性具有拮抗作用。     

血小板活化因子通过N-甲基-D-天(门)冬氨酸/突触后密度蛋白93途径致神经元损伤

目的探讨血小板活化因子(PAF)所致的神经元损伤是否涉及N-甲基-D-天(门)冬氨酸／突触后密度蛋白93(NMDA／PSD93)信号通路。方法细胞培养系统培养原代野生型和PSD93基因敲除型小鼠皮质神经元;0．3umol／LPAF处理神经元24h或5umol／LPAF受体拮抗剂(BN52021),10umol／L非竞争性NMDA受体拈抗剂(MK-801)和60umol／L神经性一氧化氮合成酶(nNOS)抑制剂(L—NAMA)预处理,碘化物／钙黄绿素染色检测细胞凋亡;免疫印迹检测野生型和基因敲除型小鼠皮质神经元中的多种蛋白表达;细胞免疫组化和共聚焦显微镜观察在同一神经轴突上共同表达多种蛋白;放免法测定神经元细胞蛋白中环鸟苷磷酸(cGMP)活性。结果(1)PSD93基因敲除型神经元不表达PSD93外,与野生型一样表达PSD93N-甲基-D-天(门)冬氨酸受体(NR2A)和nNOS。(2)神经轴突共同表达PSD93、NR2A和nNOS。(3)PSD93基因敲除型小鼠皮质神经元减少PAF对神经的毒性作用,并降低其cGMP活性。结论PAF通过NMDA／PSD93途径致神经细胞损伤。     

高钾诱导培养的小脑颗粒神经元凋亡

采用四唑盐比色、琼脂糖凝胶电泳、乙二酸荧光素染色和Hoechst33258 染色等方法研究高钾对原代培养的大鼠小脑颗粒神经元的毒性作用及其机制。结果发现：①高钾诱导神经元死亡呈剂量（50－100mmol/L）和时间依赖性;②神经元死亡呈现明显的凋亡特征：胞体缩小,染色质浓缩,DNA“梯形”条带形成和蛋白质合成抑制剂（cycloheximide,1.0mg/L)可阻断其毒性等;③MK－801（2μmol/L)、尼莫地平（10μmol/L）、硫酸镁（20μmol/L）可阻断高钾的大部分毒性作用。结果提示：高钾可能通过刺激内源性谷氨酸释放从而诱导小脑颗料神经元凋亡。     

N-乙酰半胱氨酸抗谷氨酸诱导海马神经元损伤的研究

目的　观察N-乙酰半胱氨酸(N- acetylcysteine,NAC)对不同浓度谷氨酸(Glutamte,Glu)诱导海马神经元损伤的影响,探讨其作用机制,评价毒性作用。方法　采用台盼蓝活细胞拒染与TUNEL法比较不同浓度NAC预处理3d给药与细胞毒性暴露后快速给药对10 0μmol/ L、5 0 0μm ol/ L Glu诱导体外培养海马神经元损伤的影响,并与MK- 80 1比较;利用激光扫描共聚焦显微镜(L SCM)观测细胞内Ca2 浓度变化;采用台盼蓝活细胞拒染、原子力显微镜(AFM)及细胞内酯酶活性判定方法评价NAC毒性。结果　NAC可降低10 0μmol/ L Glu诱导的海马神经元死亡率,以预处理组为佳,1m mol/ L NAC预处理保护效果类似于10μmol/ L MK - 80 1;NAC对5 0 0μm ol/ L Glu诱导的海马神经元损伤无保护作用。1mm ol/ L NAC预处理抑制Glu诱导的神经元Ca2 内流。经10 0 mmol/ L NAC作用的细胞虽然形态完整,但台盼蓝染色蓝染,失去对Glu毒性的反应性;AFM扫描见神经元细胞膜皱缩;培养基Ca2 经Fluo- 3(AM)标记后L SCM下无激发荧光。结论　NAC对轻度Glu细胞毒性损伤有保护作用,预防性用药效果更优越。认为抑制Glu诱导的神经元Ca2 内流为其保护机制之一。高浓度NAC具有固定作用     

The effect of age of onset of PD on risk of dementia

Background Dementia occurs in the majority of patients with Parkinson’s disease (PD). Late onset of PD has been reported to be associated with a higher risk for dementia. However, age at onset (AAO) and age at baseline assessment are often correlated. The aim of this study was to explore whether AAO of PD symptoms is a risk factor for dementia independent of the general effect of age. Methods Two community-based studies of PD in New York (n = 281) and Rogaland county, Norway (n = 227) and two population-based groups of healthy elderly from New York (n = 180) and Odense, Denmark (n = 2414) were followed prospectively for 3–4 years and assessed for dementia according to DSM-IIIR. All PD and control cases underwent neurological examination and were followed with neurological and neuropsychological assessments. We used Cox proportional hazards regression based on three different time scales to explore the effect of AAO of PD on risk of dementia, adjusting for age at baseline and other demographic and clinical variables. Findings In both PD groups and in the pooled analyses, there was a significant effect of age at baseline assessment on the time to develop dementia, but there was no effect of AAO independent of age itself. Consistent with these results, there was no increased relative effect of age on the time to develop dementia in PD cases compared with controls. Interpretation This study shows that it is the general effect of age, rather than AAO that is associated with incident dementia in subjects with PD. Received in revised form: 22 December 2005     

帕金森病运动症状进展分析

目的分析帕金森病(PD)患者运动症状进展特点。方法采用PD统一评分量表(UPDRS)Ⅲ对912例PD患者进行评估。结果与病程1年的患者比较,除病程1~2年的患者外,其他病程患者的UPDRSⅢ评分、强直分、姿势或步态异常分、轴性症状总分、言语分、步态分显著升高(均P0.05),病程5~6年及14年患者的震颤分,病程5~6年、7~8年、9~13年、14年患者的运动迟缓分、姿势分显著升高(P0.05~0.01)。轴性症状进展速度高于UPDRSⅢ评分。结论 PD患者病程早期UPDRSⅢ评分进展快,震颤症状进展独立于其他症状,轴性症状评分较UPDRSⅢ更敏感地反映疾病加重趋势。     

Frequency of accumulation of filaments in adaxonal cytoplasm of Schwann cells of myelinated fibers of rat spinal roots

Summary The frequency of accumulation of 6-nm filaments in the adaxonal cytoplasm of Schwann cells in the 6th lumbar dorsal and ventral roots was evaluated in 4-, 8-, 26- and 45-week-old Sprague-Dawley rats. The frequency was higher in 4- and 8-week-old (growing) rats than in 26- and 45-week old (mature) rats, and also higher in ventral than in dorsal roots in 4-, 8- and 26-week old rats. There were no clusters on certain groups of myelinated fibers according to the size of transverse axonal area, in both the ventral and dorsal roots. Therefore, this accumulation may reflect certain functions of the adaxonal cytoplasm of Schwann cell during natural growth and maturation of the axon and myelin sheath.     

Function of circle of Willis

Nearly 400 years ago, Thomas Willis described the arterial ring at the base of the brain (the circle of Willis, CW) and recognized it as a compensatory system in the case of arterial occlusion. This theory is still accepted. We present several arguments that via negativa should discard the compensatory theory. (1) Current theory is anthropocentric; it ignores other species and their analog structures. (2) Arterial pathologies are diseases of old age, appearing after gene propagation. (3) According to the current theory, evolution has foresight. (4) Its commonness among animals indicates that it is probably a convergent evolutionary structure. (5) It was observed that communicating arteries are too small for effective blood flow, and (6) missing or hypoplastic in the majority of the population. We infer that CW, under physiologic conditions, serves as a passive pressure dissipating system; without considerable blood flow, pressure is transferred from the high to low pressure end, the latter being another arterial component of CW. Pressure gradient exists because pulse wave and blood flow arrive into the skull through different cerebral arteries asynchronously, due to arterial tree asymmetry. Therefore, CW and its communicating arteries protect cerebral artery and blood–brain barrier from hemodynamic stress.     

Effects of prevention of afferentation of the development of the chick optic lobe

BONDY, S. C., M. E. HARRINGTON AND C. L. ANDERSON. Effects of prevention of afferentation on the developmentof the chick optic lobe. BRAIN RES. BULL. 3(5) 411–413, 1978.—The effects of unilateral extirpation of the right optic cup of the three-day incubated chick embryo upon the rate of synthesis and the stability of DNA in the non-innervated optic lobe, have been studied. This surgical procedure prevents innervation of the optic lobe contralateral to the removed eye, while the other optic lobe is normally innervated by retinal ganglion cells of the remaining eye. At the 20th day of incubation, the DNA content of the non-innervated lobe was below that of the paired lobe receiving normal innervation. This deficiency of cell number was caused by two events; death of an excess number of neurons formed early in embryogenesis and a reduced rate of glial proliferation in the later stages of incubation.     

Modelling of movement of the lamprey: Control of oscillators

This article discusses the control methods of the central pattern generator (CPG). First a control model of the CPG is presented using 2 oscillators, and we suggest that phasic modulation to the CPG by means of phasic information is effective for controlling the phase difference between oscillators. Next, two models for controlling the CPG of a lamprey are proposed. One model describes a control system from the brain stem, in which the reticulospinal neurons control the CPG by receiving feedback signals and sending control signals to the neck region of the CPG. The other is a model for learning an localized control system to generate a desired motor pattern. By means of these models, a role of the efference copy is suggested.     

腺垂体功能减退症临床特征变化分析

目的探讨腺垂体功能减退症患者的病因结构变化及临床表现。方法回顾性分析我院2013-01—2016-12住院及门诊78例腺垂体功能减退症患者的临床资料。结果男32例(41.03%),女46例(58.97%);诊断时年龄11~89岁,平均62.5岁;鞍区占位(包括术前及术后)52例(66.67%),席汉综合征8例(10.26%),空泡蝶鞍9例(11.65%),病因不明8例(10.26%),垂体-下丘脑发育不良1例(1.28%)。首次就诊科室:纳差厌食、恶心呕吐就诊于消化内科36例(46.15%)最常见。ACTH+TSH+Gn+G激素缺乏为19例最多,占24.36%,ACTH+TSH+Gn缺乏15例,占19.23%。结论腺垂体功能减退症病因结构发生变化,发病人群、首发症状及受累激素也不同,患者女性多于男性,发病年龄偏高,症状不典型,分布于临床多个科室,其中以低钠血症为首发临床表现就诊消化内科最多。     

Standards of instrumentation of EMG

Standardization of Electromyography (EMG) instrumentation is of particular importance to ensure high quality recordings. This consensus report on “Standards of Instrumentation of EMG” is an update and extension of the earlier IFCN Guidelines published in 1999. First, a panel of experts in different fields from different geographical distributions was invited to submit a section on their particular interest and expertise. Then, the merged document was circulated for comments and edits until a consensus emerged.The first sections in this document cover technical aspects such as instrumentation, EMG hardware and software including amplifiers and filters, digital signal analysis and instrumentation settings. Other sections cover the topics such as temporary storage, trigger and delay line, averaging, electrode types, stimulation techniques for optimal and standardised EMG examinations, and the artefacts electromyographers may face and safety rules they should follow. Finally, storage of data and databases, report generators and external communication are summarized.     

利培酮对精神分裂症患者生活质量的影响

目的：比较利培酮与氟哌啶醇对精神分裂症患者生活质量的影响。方法：对门诊72例服用氟哌啶醇及74例服用利培酮的精神分裂症患者用生活质量综合评定问卷（GQOLI）、阳性与阴性症状量表（PANSS）、副反应量表（TESS）进行评定。结果：利培酮组患者治疗后生活质量有所提高,而氟哌啶醇组患者生活质量有所下降。结论：利培酮治疗有利于患者提高生活质量。     

Effect of high simple dose of cisplatinum and of radiation on the brain of rabbit

Abstract

In former studies of intracarotid and intravenous administration of cisplatinum, separate and combined with brain irradiation, we found no cerebral damage. In this study! gradually increasing high doses (above the therapeutic ones) of cisplatinum were administered intravenously to one series of rabbits arid increasing high amounts of irradiation (above the therapeutic amounts) were given to another series. Although the rabbits that received highest doses of irradiation developed areas of alopecia and skin ulcers on the head! the general clinical and histopathologic examination of the rabbits brains in both series was normal. The purpose of this study was to establish the effects of high doses of intravenous cisplatinum and irradiation on the rabbits brains. [Neural Res 1997; 19: 216–218]