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1.
晚发性抑郁患者情绪调节机制的ERPs研究 总被引:4,自引:0,他引:4
目的采用事件相关电位探讨晚发性抑郁患者情绪调节障碍的神经生理机制。方法被试者包括16例晚发性抑郁患者(发病年龄≥60岁)与16名健康老年人。采用Go/Nogo实验范式,要求被试者对刺激序列中双个三角形进行按键反应(Go),单个三角形不反应(Nogo)。记录32导脑电。结果健康老年人中,Nogo刺激产生了明显的额中央区分布的N2Nogo和P3Nogo;与对照组相比,病例组的N2Nogo。波幅明显增高,而P3Nogo波幅显著降低,两者潜伏期无显著差异。结论晚发抑郁患者存在情绪调节障碍,其电生理学指标为N2Nogo明显增高和P3Nogo的显著降低,为晚发性抑郁的诊断和治疗提供了一定的客观评价指标。 相似文献
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Nakata H Inui K Wasaka T Tamura Y Kida T Kakigi R 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,162(3):293-299
The present study investigated the characteristics of the middle-latency negative potential of event-related potentials (ERPs) using somatosensory go/nogo tasks. We manipulated interstimulus interval (ISI) in Experiment 1 and stimulus probability in Experiment 2 and analyzed the subtracted difference waveform resulting from subtraction of the ERP evoked by the go stimulation from that evoked by the nogo stimulation. In Experiment 1, the peak latency of negativity became significantly longer as the ISI increased, but the peak amplitude was unchanged. The reaction time (RT) was longer with increasing ISI. In Experiment 2, manipulation of the stimulus probability yielded an increase in peak amplitude with decreasing probability of the nogo stimulus, but did not affect the latency. The RT increased as the probability of a nogo stimulus rose. Because manipulation of the ISI and stimulus probability elicited different brain activities, we hypothesized that manipulation of the ISI elicited a delay of the stimulus evaluation process including response inhibition, and that stimulus probability significantly affected the strength of the response inhibition process. 相似文献
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目的:构建大鼠Nogo受体(Nogo receptor,NgR)基因RNA干扰慢病毒表达载体,并观察其对293T细胞感染效率.方法: 应用基因工程技术,首先构建携带目的基因siNgR199的慢病毒穿梭质粒表达载体,然后使用慢病毒包装质粒混合物和构建好的慢病毒穿梭质粒共转染293T细胞,转染48 h后收集上清离心过滤后冰浴保存,最后进行病毒滴度测定,与标准病毒液分别感染293T细胞,按MOI值分为5个梯度:1、3、5、10、20,以确定病毒滴度及适合感染的MOI值.其中采用PCR方法对重组载体进行鉴定,利用绿色荧光蛋白作为报告基因,对病毒滴度和感染效率进行检测.结果: 酶切鉴定及PCR结果与病毒载体的预期结果一致,病毒滴度达1×108 ifu/m1,适合感染的MOI值为3.结论: 应用基因工程技术,成功构建了大鼠siNgR199慢病毒表达载体,为应用于治疗脊髓损伤后轴突再生创造了条件. 相似文献
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目的观察电针对脊髓损伤大鼠Nogo/NgR信号通路相关因子基因表达变化,探讨电针治疗脊髓损伤的可能作用机制。方法大鼠随机分为模型组、电针组、阻断剂组、电针+阻断剂组、假手术组,用改良Allen’s撞击法制备T10脊髓损伤模型,分别于治疗后1、7、14 d对各组大鼠进行BBB功能评分;在7、14 d于损伤处提取脊髓组织,以蛋白印迹法(Western blot)测定各组大鼠脊髓组织中Nogo-A、NgR、LINGO-1蛋白的表达变化,实时荧光定量PCR测定Nogo-A、NgR、LINGO-1 mRNA的表达变化。结果脊髓损伤后,造模大鼠1 d后BBB评分均为0分;治疗7、14 d后,各治疗组BBB评分均明显高于模型组(P0.05),且电针+阻断剂组优于电针组、阻断剂组(P0.05)。与假手术组比较,同时间点模型组各基因表达均明显提高(P0.05);与模型组比较,各治疗组基因表达明显下降(P0.05);电针+阻断剂阻组与电针组比较,同时间点LINGO-1基因表达有显著差异(P0.05)。结论 Nogo/NgR信号通路在脊髓损伤后神经的再生与修复过程中起着关键作用,电针通过抑制Nogo/NgR信号通路而对脊髓损伤大鼠起治疗作用。 相似文献
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Katarzyna Drożdż Irmina Grzegorek Magdalena Chmielewska Agnieszka Gomułkiewicz Karolina Jabłońska Aleksandra Piotrowska Maciej Karczewski Dariusz Janczak Dariusz Patrzałek Piotr Dzięgiel Andrzej Szuba 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2014,122(9):742-749
Nogo‐B (Reticulon 4B) is considered to be a novel vascular marker, which may have a protective role in injury‐induced neointima formation and atherosclerosis. Nogo A/B is found to be crucial for monocyte/macrophage recruitment in acute inflammation and it is expressed in CD68 + macrophages. We hypothesize that macrophage infiltration in atherosclerosis is not dependent on Nogo‐B expression in arterial wall. We have assessed Nogo‐B expression and macrophage accumulation in the iliac arteries of healthy organ donors and organ donors with cardiovascular risk factors. Paraffin sections of 66 iliac arteries, from 44 deceased organ donors (17 women and 27 men), were studied. The healthy and cardiovascular risk (CVR) subgroups were created. With regard to staging of the atherosclerotic process, the thickness of arterial intima was measured in digitalized images of H+E stained tissue sections. Immunohistochemical reactions (Nogo‐B and CD68) were carried out in all arteries (66 samples). Western blotting (WB‐19 samples) and real‐time PCR (27 samples) were performed on selected arteries. Significantly higher Nogo‐B expression was demonstrated in the intima of the healthy subjects' subgroup, using immunohistochemistry. WB and real‐time PCR revealed a trend toward lower Nogo‐B expression in the adventitia of the CVR subgroup. Furthermore, the thickness of the intima was found to negatively correlate with the expression of Nogo‐B in the intima and media (r = ?0.32; p < 0.05; r = ?0.32; p < 0.05). Macrophage infiltrates were more prominent in intima of CVR subjects (0.65 vs 3.52 a.u.; p < 0.01). Macrophage density in intima increased with atherosclerosis progression (r = 0.37; p < 0.01). CD68 macrophages density in adventitia was lower in CVR arteries than in healthy arteries. The expression of Nogo‐B, in arterial intima, is impeded in the early stages of atherosclerosis. Accumulation of arterial intimal CD68 macrophages has been shown to progress; however, the overall macrophage density in the adventitia is reduced in arteries shown to have intimal thickening. Macrophage infiltration is not accompanied by Nogo‐B expression in atherosclerotic arteries. 相似文献
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Background: The mammalian central nervous system is incapable of substantial axon regeneration after injury partially due to the presence of myelin‐associated inhibitory molecules including Nogo‐A and myelin associated glycoprotein (MAG). In contrast, axolotl salamanders are capable of considerable axon regrowth during spinal cord regeneration. Results: Here, we show that Nogo‐A and MAG, and their receptor, Nogo receptor (NgR), are present in the axolotl genome and are broadly expressed in the central nervous system (CNS) during development, adulthood, and importantly, during regeneration. Furthermore, we show that Nogo‐A and NgR are co‐expressed in Sox2 positive neural progenitor cells. Conclusions: These expression patterns suggest myelin‐associated proteins are permissive for neural development and regeneration in axolotls. Developmental Dynamics 242:847–860, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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Neuronal Nogo‐A in New‐born Retinal Ganglion Cells: Implication for the Formation of the Age‐related Fiber Order in the Optic Tract
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Nogo‐A is highly expressed in oligodendrocytes in the adult central nervous system (CNS). Recently it was found that Nogo‐A is also expressed in some neuronal types during development. Here, we examined the expression pattern of Nogo‐A in both the retina and optic tract (OT) of mouse embryos from E12 to E15. After perturbation of its function in the OT for 5 hr in the brain slice culture system using a Nogo‐A specific antibody or antagonist of its receptor (NEP1‐40), the optic nerve fibers and growth cones were traced with DiI. We showed that most Tuj‐1 positive new‐born neurons at E12 were Nogo‐A positive. At E15, retinal neurons reduced the Nogo‐A expression. It was worth noting that some projecting axons expressed Nogo‐A along the retinofugal pathway. On the basis of their specific locations within the superficial half of the OT and the colocalization with GAP‐43 (a marker for the newly born growth cones and axons), we concluded that those Nogo‐A positive axons were the newly arrived retinal fibers. Blocking the function of Nogo‐A with Nogo‐A antibody or NEP1‐40 resulted in the shift of DiI labeled axons and growth cones from the superficial half to the whole depth of the OT. These results indicate that Nogo‐A in the newly born retinal ganglion cells (RGCs) and their axons are involved in sorting out the newly arrived axons to the subpial region of the OT. Anat Rec, 299:1027–1036, 2016. © 2016 Wiley Periodicals, Inc. 相似文献