Cellular proliferation in the cerebral cortex following neural excitation in rats

Cortical spreading depression (SD) is characterized by propagation of neuronal/glial membrane depolarization throughout the unilateral cerebral cortex and has been linked to several neurological disorders, including migraine aura and epilepsy. SD induction resulted in a dramatic increase in BrdU-incorporated cells in the ipsilateral cortical hemisphere that was dependent on the number of elicited SD. Immunohistochemical studies revealed that 53% of the BrdU-labeled cells in the SD-generated cortex were NG2 immunopositive and 25% were OX-42 immunopositive. The remaining 22% of BrdU-incorporated cells showed no immunoreactivity to GST-rr, GFAP, NeuN, NG2 or OX-42.These data indicate that functional excitation of the cerebral cortex induces proliferative response in cortical cells, which may subsequently differentiate into glial progenitor or microglia within 3 days after stimulation.     

A novel bioactive 31-amino acid ET-1 peptide stimulates eosinophil recruitment and increases the levels of eotaxin and IL-5

OBJECTIVE AND DESIGN: Investigation of the role of a novel inflammatory mediator 31-amino acid endothelin-1 [ET-1 (1-31)], a major ET derivative in granulocytes, in eosinophil recruitment after its subcutaneous administration to mice. METHODS: Various ET-1 derivatives (100 pmol), with or without ET receptor antagonists (200 pmol), were administered subcutaneously to mice, and then the eosinophil migration into and chemokine levels in the injected loci were analyzed. RESULTS: ET-1 (1-31) and a 21-amino acid endothelin-1 (ET-1), but not big ET-1, induced eosinophil migration into the injected loci with a peak after administration for 12 h, and increased the levels of eotaxin and interleukin-5 with peaks at 6 and 24 h, respectively. These effects of ET-1(1-31) and ET-1 were significantly inhibited by an ETA receptor antagonist, BQ-123, but not by an ETB receptor antagonist, BQ-788. CONCLUSION: Novel bioactive ET-1 (1-31) induces local eosinophil migration, and increases in eotaxin and interleukin-5 through an ETA or ETA-like receptor.     

Retinal ganglion cell neurotrophin receptor levels and trophic requirements following target ablation in the neonatal rat

Superior colliculus (SC) ablation in neonatal rats results in a rapid increase in retinal ganglion cell (RGC) death. This injury-induced death is reduced by exogenous brain-derived neurotrophic factor or neurotrophin-4/5 (NT-4/5), but the protective effect of these molecules is transient, delaying but not preventing neuronal loss. We sought to discover why neurotrophins only temporarily reduce RGC death after target ablation, focusing on changes in neurotrophin receptor expression and possible changes in growth factor dependency. In unlesioned rats, receptor tyrosine kinase B (trkB) immunohistochemistry revealed no change in the number of trkB positive cells in the RGC layer 24 h after intraocular NT-4/5 injection. However, after SC lesions there were significantly less immunoreactive cells and, surprisingly, even fewer immunoreactive cells in NT-4/5 injected eyes. Semi-quantitative confocal analysis of immunofluorescence intensity revealed an increase in trkB staining in the RGC layer in unlesioned rats 24 h after NT-4/5 injection, whereas in SC-lesioned animals exposed to NT-4/5 there was a significant decrease in staining. To determine whether injured neonatal RGCs can switch their trophic requirements, different doses of ciliary neurotrophic factor were given intraocularly, either alone or combined with NT-4/5. We also tested an SC-derived chondroitin sulfate proteoglycan that has been reported to promote neonatal RGC survival. None of these interventions reduced lesion-induced RGC death 24 or 36 h after SC ablation. In summary, we show that developing RGCs do not shift their trophic dependence to other survival factors following injury; rather, the application of neurotrophins causes a down-regulation of the cognate trkB receptor, presumably altering the long-term responsiveness of neonatal RGCs to exogenous neurotrophins. These data highlight the difficulty in promoting long-term neuronal survival when using one-off administration of recombinant growth factors.     

咀嚼肌的应用解剖学研究——I.咬肌的动脉与神经

在30具(男23.女7)共60例成人尸体上观察与测量了咬肌的动脉与神经来源、咬肌神经的分支以及肌内构筑、咬肌由上颌动脉咬肌支和邻近动脉肌支供血,面动脉与面横动脉的咬肌支为其主要营养动脉.咬肌神经在肌内可分成单干和双干两型,前者居多,两型中其肌内分支间均有吻合.就结果对有关颌面外科应用问题进行了探讨.     

心肌炎患者高频心电图QRS波群的功率谱分析

本文选取６９名心肌炎患者，９４名正常人做为对照。依其年龄不同，共分６组：幼儿心肌炎组，正常幼儿组，学龄心肌炎组，正常学龄组，成人心肌炎组，正常成人组。分别对这６组的Ⅱ导、ａＶＦ导、Ｖ２导、Ｖ５导ＱＲＳ波群０－１０００Ｈｚ、８０－３００Ｈｚ、１００－１０００Ｈｚ３个频段的功率谱（用绝对能量表示）进行了分析。结果提示，不同年龄的心肌炎患者，其心电信号高频频段的能量变化规律不一致。     

N-氨基-D-门冬氨酸诱导大鼠下丘脑视上核、室旁核和弓状核内c-fos基因表达

实验用foS蛋白免疫组织化学方法,研究了中枢神经系统兴奋性介质N-氨基-D-门冬氨酸诱导大鼠下丘脑内c-fos的表达.N-氨基-D-门冬氨酸注射大鼠皮下后,观察了fos阳性细胞在下丘脑内开始出现与消失的时程相关以及在下丘脑内的分布.结果表明:给N-氨基-D-门冬氨酸后30分开始出现fos阳性细胞,1～2小时达高峰,4～8小时消失.fos阳性细胞主要分布于视上核、室旁核和弓状核,视上核和室旁核中fos阳性细胞分别占细胞总数的57.8%和63.6%,在弓状核中占细胞总数的60.6%.     

Human granulocyte-macrophage colony-stimulating factor (hGM-CSF): identification of a binding site for a neutralizing antibody.

One approach to the localization of functionally active regions of human granulocyte-macrophage colony-stimulating factor (hGM-CSF) is to map the epitopes recognized by neutralizing anti-hGM-CSF monoclonal antibodies. We have defined the epitope recognized by one neutralizing antibody (LMM102) using proteolytic fragments obtained by enzymic digestion of bacterially synthesized hGM-CSF. RP-HPLC fractionation of a tryptic digest resulted in the identification of an immunoreactive "tryptic core" peptide containing 66 amino acids (52% of the protein). Further digestion of this "tryptic core" with S. aureus V8 protease produced a unique immunoreactive hGM-CSF product comprising two peptides, residues 86-93 and 112-127, linked by a disulfide bond between residues 88 and 121. The individual peptides, generated by reduction with dithiothreitol, were not recognized by the antibody. An analog of this peptide has been synthesized chemically and shown to have similar immunoreactivity to the epitope obtained by enzymic digestion. A series of modified peptides has also been synthesized to identify further the region required for antibody recognition.     

经单侧穿刺椎体后凸成形术治疗侧方椎体压缩性骨折

目的研究经单侧椎弓根穿刺椎体后凸成形术治疗侧方骨质疏松性椎体压缩骨折(osteoporotic vertebral compression fractures,OVCF)的疗效。方法选择我院2009年10月~2011年10月收治的30例侧方OVCF患者,随机行凹侧或双侧球囊撑开椎体后凸成形术治疗,分别在术后1、6、12个月进行随访,对椎体高度恢复、脊柱后凸、侧凸Cobb角及并发症进行评价。结果术后1、6、12个月的随访结果比较发现,凹侧撑开及双侧撑开组患者椎体高度均较术前明显恢复(P0.05),脊柱后凸、侧凸Cobb角均较术前明显纠正(P0.05)。术后定期随访无丢失。凹侧撑开组与双侧撑开组之间比较,上述指标差异无统计学意义(P0.05)。结论经凹侧球囊撑开椎体成形治疗侧方OVCF,与双侧撑开相比疗效相当,可简化手术、缩短手术时间、减小创伤、减少费用,是治疗侧方OVCF的有效方式。