Interactional expertise through the looking glass: a peek at mirror neurons

Interactional expertise is here to stay. Undoubtedly, in some sense of the word, one can attain a linguistic expert level within a field without full scale practical immersion. In the context of the idea of embodied cognition, the claim is provocative. How can an interactional expert acquire full linguistic competence without the simultaneous bodily engagement and real life interaction needed to get the language right? How can one understand the concept of hammering if one has never seen a hammer or felt the weight of the iron head on a fragile thumb? Here I will explore a strange and second-hand way in which bodily engagement could have an impact on our linguistic abilities; this is via the so called mirror neuron system. Since the mirror neuron system blurs the distinction between first and third person activity it can help us understand some of the enigmatic aspects of interactional expertise and pose further questions for research.     

Effect of thrombin on the apoptosis of hippocampal neurons in vitro

Hippocampal neurons were treated by thrombin and thrombin receptor activating peptides (TRAP). Cell survival rate was decreased in a dose-dependent manner by MTT assay. The numbers of apoptotic cell and apoptotic rate of hippocampal neurons treated by different concentrations of thrombin were increased in a dose-dependent manner by terminal deoxynucleotidyl transferase (TdT) mediated dUTP-biotin nick end-labeling (TUNEL) method and Flow Cytometry. When the concentration of thrombin is 40 U/mL, TUNEL positive cells and apoptotic rate of hippocampal neurons reached peak value, were 27.3±4.0 and (29.333±4.633)%, respectively. Immunocytochemistry assay show that Bcl-2 protein expression was down-regulated and Bax protein expression was up-regulated with the concentration of thrombin increased. TRAP can mimic the effect of thrombin to induce apoptosis on hippocampal neurons. These data demonstrated that thrombin induced hippocampal neuron apoptosis in a dose-dependent manner through activating protease-activated protein-1 (PAR-1). The change in expression of Bcl-2 and Bax was related with the effect of high concentration thrombin induced apoptosis on hippocampal neurons. Foundation item: Supported by the Natural Science Foundation of Hainan Province (N30215) Biography: YANG Wen-qiong (1968-), female, Ph.D. candidate, research direction: cerebrovascular disease.     

鸣禽前脑鸣啭控制核团内胆碱能神经元的分布

高级发声中枢（HVC）和古纹状体粗核（RA）是位于鸣禽前脑的两个主要鸣啭控制核团，以中国北方地区常见的两种鸣禽栗鹂（Emberiza rutila)和燕雀（Fingilla montifringilla）为材料，应用免疫组化方法，对两种鸣禽HVC和RA内胆碱能神经元的胞体大小和密度进行了观察、发现ChAT样免疫反应具有性别差异。这一结果提示胆碱能神经元可能在鸣啭的产生和学习过程中发挥着重要的作用。     

血竭对大鼠背根神经节细胞钠通道电流的影响

研究血竭对大鼠背根神经节细胞电压门控性钠通道电流的影响。方法：采用全细胞膜片钳记录法，在新鲜分离的大鼠背根神经节细胞上观察血竭对钠通道电流幅值的影响。结果：血竭剂量依赖地抑制单个DRG细胞电压门控性钠通道电流，高剂量的血竭抑制作用不可逆。结论：血竭对背根神经节细胞钠通道电流的这种抑制作用，可能是其产生躯体镇痛作用的药理机制之一。     

低信噪比神经元锋电位信号的分类方法

基于离散序列小波变换和主元分析，对低信噪比的神经元锋电位信号提出了新的分类方法。通过对原始信号进行尖峰检测，获得尖峰信号样本，对每个样本进行离散序列小波变换之后，再对小波变换系数进行主元分析，选取主元进行聚类，实现对原始信号的分类。将该方法应用于多电极细胞外记录的小鸡视网膜神经节细胞电活动信号分析，并据此推断出某电极附近的神经节细胞的个数。仿真结果表明，在低信噪比情况下，该方法比单纯通过小波变换进行分类的方法更有效。     

多不饱和脂肪酸对谷氨酸诱导的大鼠海马神经细胞损伤的双重影响

通过测定原代培养的谷氨酸诱导的受损海马神经的细胞存活率,谷胱甘肽过氧化物酶活性,以及谷胱甘肽和一氧化氮的水平,研究多不饱和脂肪酸,如二十二碳六烯酸(docosahexaenoic acid,DHA)、花生四烯酸(arachidonic acid,AA),对大鼠海马神经细胞损伤的影响.海马神经元用神经特异性烯醇化酶进行鉴定.研究发现:(1)DHA 5～50 mg/L能有效的对抗谷氨酸诱导的海马神经细胞的损害作用.表现在细胞存活率、谷胱甘肽过氧化物酶的活性较谷氨酸处理组明显提高,NO水平降低,谷胱甘肽含量与对照组相比变化不大.(2)5 mg/LAA对损伤没有影响,而30和50 mg/LAA对损伤具有加重作用,其细胞存活率、GSH-Px活性、GSH水平较谷氨酸处理组明显降低.结果表明,多不饱和脂肪酸对谷氨酸诱导的神经细胞损伤具有双重作用.     

Effect of New O-Superfamily Conotoxin on Voltage-Activated Currents of Hippocampal Neurons

The effects of a new O-superfamily conotoxin, SO3, on sodium current (INa), transient A-type potassium currents (IA), and delayed rectified potassium currents (IK), were examined in cultured rat hippocampal neurons using the whole-cell patch clamp technique. Addition of SO3 caused a concentration-dependent, rapidly developing, and reversible inhibition of voltage-activated currents. The IC50 values for the blockage of INa, IA, and IK were calculated as 0.49, 33.9, and 7.6 μmol/L, respectively. The determined Hill coefficients were 1.7, 0.6, and 1.2, respectively. These results indicate that SO3 can selectively inhibit neuronal sodium and potassium currents.     

双稳反应扩散系统的棱锥形行波解

研究了双稳型反应扩散系统在空间Rm (m4)中的棱锥形行波解的存在性.主要的方法是使用比较原理和构造适当的上下解.     

卡尔曼滤波器在海马场电位ripple节律分析中的应用

利用自适应自回归(adaptive autoregressive,AAR)模型和卡尔曼滤波器算法,分析小鼠海马CA1区场电位ripple高频振荡的时频特性.研究发现,与传统的基于短时傅立叶变换的实时频谱分析方法相比,利用AAR模型以及卡尔曼滤波器算法的参数化方法在对ripple高频振荡信号进行实时频谱分析时,具有更高的...