定量评估64层螺旋CT血管成像与DSA显示冠状动脉狭窄的能力和可靠性

目的定量评估64层螺旋CT（MSCT）与DSA2种成像方法显示冠状动脉狭窄及支架内再狭窄的能力和可靠性。方法应用心脏动态体模，设定心率为0、50、70、90次／min，对内径3mm的模拟冠状动脉（内设25％、50％、75％3段狭窄）及内径4mm的模拟带支架冠状动脉（支架段内设50％、75％2段狭窄）分别进行MSCT与DSA成像，将MSCT与DSA对应数据进行分析。结果（1）MSCT对25％、50％、75％3段狭窄的平均测量值为（30．0±1．4）％、（49．5±1．3）％、（72．9±3．9）％（P值分别为0．005、0．531、0．369）；DSA分别为（24．8±2．0）％、（48．2±2．1）％、（75．3±2．4）％（P值分别为0．883、0．180、0．796）。（2）MSCT图像伪影随心率增快而增加，心率≥70次／min影响变明显；DSA不受心率影响，所有心率下都可清晰地显示狭窄程度，无伪影。（3）MSCT与DSA测量血管狭窄程度有较好的相关性（r=0．995，P=0．000）。（4）MSCT可同时显示支架及支架内狭窄，但显示支架内狭窄能力有限，对50％狭窄分别显示为（46．4±4．5）％（心率为0）和（43．6±5．7）％（心率为50次／min），与标准值（50％）相比，差异有统计学意义（P〈0．05）。DSA可清晰显示支架内狭窄，但不能很好显示支架形态。结论（1）MSCT与DSA评价冠状动脉狭窄结果可靠，MSCT受心率的影响大，时间分辨率有待提高，作为排除性诊断有很高的临床应用价值；MSCT对于支架内再狭窄的判断尚有一定局限性，但在管径较粗和低心率条件下评价支架内再狭窄有一定价值。     

Spinal Cord Stimulation in a Mouse Chronic Neuropathic Pain Model

Objective. Development of a spinal cord stimulation (SCS) system in a mouse model of chronic neuropathic pain. Materials and Methods. Male C57BL/6 mice (N = 6) underwent a partial ligation of the sciatic nerve. Development of mechanical hyperalgesia was tested using the withdrawal response to tactile stimuli with the von Frey test. An SCS system was implanted on day 14. On day 16, the mice were stimulated for 30 min (f = 50 Hz; pulse width 0.2 msec and stimulation at 2/3 of motor threshold). Repeated measure analysis of variance (anova ) and paired Student's t‐test with Bonferroni correction were used to evaluate the development of mechanical hyperalgesia and the therapeutic effect of SCS. Results. Five out of six mice developed marked mechanical hyperalgesia in the nerve‐lesioned paw that persisted for the duration of the study (16 days). No changes contralateral to the injury were observed. In four out of five mice, a successful implantation of the electrodes followed by stimulation was achieved. Then, SCS resulted in a fast and robust increase of withdrawal threshold back to pre‐injury levels. After termination of the SCS, the withdrawal threshold of the ipsilateral paw slowly decreased. No effect of SCS on the contralateral paw was noted. Conclusion. The development of a mouse SCS system is described that is practical in use, is reproducible, and shows a comparative therapeutic effect in treatment of chronic neuropathic pain as reported in rat.     

角蛋白人工腱膜预防全椎板切除术后硬脊膜黏连

[目的]探讨角蛋白（keratinsubstance，KS）人工腱膜材料用于预防全椎板切除术后硬脊膜黏连的效果。[方法]Wistar大白鼠60只，随机分3组，每组20只，咬除T。：全椎板，造成2rnrnX8rnlffl大小的椎板缺损，加入不同处理因素，A组：空白对照组；B组：人工腱膜组；C组：白体腱膜组。术后2、4、8，12周处死动物，各时间点大体观察采用Rydell瘢痕黏连程度评级标准评分。完整取出T。：节段，包括椎旁肌。经HE染色后，镜下组织学观察采用改良Nussbaum标准行评分。同时切取2，4、8、12周人工腱膜组硬膜外瘢痕组织进行透射电镜观察。所测数据行Kruskal—Wallis秩和检验，取a〈0．05作为统计显著差异的标准。[结果]KS人工腱膜材料无毒性和排异反应：A组的Rydell评分，改良Nussbaum评分高于B、C组（P〈0．05），B组C组比较无差别（P〉0．05）。B、C组与对照组比较，均能够明显减少椎板切除术后的硬膜外瘢痕形成。[结论]硬膜外瘢痕黏连主要来自硬膜后方的血肿和成纤维细胞（fibroblast，FB）的增殖。KS人工腱膜具有良好的组织相容性，无局部及全身的不良反应，具有良好物理屏障作用。将l（S人工腱膜放置在椎板缺损处，能够有效的防止纤维组织侵入椎管，预防硬膜外瘢痕黏连。在动物实验中，KS人工腱膜能够安全有效的预防椎板切除术后硬膜外瘢痕黏连。     

大剂量甲基强的松龙在胸椎管狭窄症围手术期应用的效果观察

目的:探讨大剂量甲基强的松龙(MP)在胸椎管狭窄症患者围手术期应用的效果。方法:84例胸椎管狭窄症患者均行椎板切除减压术,并将其分为2组,A组,围手术期应用大剂量MP组,36例,术中进椎管前静脉给予MP 30mg/kg,15min滴完;术后静脉应用MP(80mg/d)3d。B组,围手术期应用氟美松治疗组,48例,术后静脉应用氟美松(10mg/d)3d。比较两组患者手术前后的神经功能变化情况(JOA评分17分法),并对计量资料行t检验。结果:术前JOA评分A组为8.58±2.62分,B组为9.12±2.81分,两组间无显著性差异(P>0.05)。术后1周时A组为13.65±2.16分,B组为11.12±2.36分;术后3个月时A组为14.11±2.21分,B组为12.62±2.35分,两组间比较均有显著性差异(P<0.05)。B组有9例患者术后即刻出现神经功能障碍加重,而A组未出现类似病例。结论:围手术期应用大剂量MP对胸椎管狭窄症患者的脊髓功能有保护作用。     

腰椎间盘突出症患者腰腿痛的血循环障碍因素与推拿手法的促循环作用机制

推拿手法长期以来被广泛用于腰椎间盘突出症的治疗．但其疗效机制却不甚明了。腰椎间盘突出症最具特征性的临床症状是不同程度的腰腿痛，其发病机制主要是机械压迫、无菌性炎症刺激以及循环与营养障碍等因素导致受累神经根传导功能的障碍，其中血循环与营养障碍是腰腿痛发病的重要环节。手法治疗对患者腰腿痛的缓解与消除作用应与改善患者的血循环和营养障碍有直接或间接的关系。     

Neuroprotective effect of estrogen after chronic spinal cord injury in ovariectomized rats

BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries. OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats. DESIGN: A randomized controlled animal trial. SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University. MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point. METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days. MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively. RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05). CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury.     

Engineering angiogenesis following spinal cord injury: a coculture of neural progenitor and endothelial cells in a degradable polymer implant leads to an increase in vessel density and formation of the blood–spinal cord barrier

Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair.     

一期后、前路手术治疗发育性颈椎管狭窄症合并巨大椎间盘突出

目的：评价一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出的特点及疗效。方法：回顾分析2002年2月至2006年1月接受该术式的21例患者的临床资料,对手术前后临床表现、JOA评分、MRI影像变化以及术后神经功能改善率及并发症进行总结分析。结果：术后未发生神经系统症状加重、感染及内固定失效等并发症。获得1年以上随访者21例,平均随访时间为29.2个月,术后3个月、12个月时神经功能改善率分别为：58%、66%;16例获得2年以上随访者神经功能改善率为71%。结论：一期后、前路手术治疗发育性颈椎管狭窄合并巨大椎间盘突出可缩短治疗周期,相对节省治疗费用,同时解除了硬膜囊前、后方的压迫,减压彻底,疗效满意。     

Role of proteasomes in the formation of neurofilamentous inclusions in spinal motor neurons of aluminum‐treated rabbits

We examined the role of the 20S proteasome in pathologic changes, including abnormal aggregation of phosphorylated neurofilaments, of spinal motor nerve cells from aluminum‐treated rabbits. Immunohistochemistry for the 20S proteasome revealed that many lumbar spinal motor neurons without intracytoplasmic neurofilamentous inclusions or with small inclusions were more intensely stained in aluminum‐treated rabbits than in controls, whereas the immunoreactivity was greatly decreased in some enlarged neurons containing large neurofilamentous inclusions. Proteasome activity in whole spinal cord extracts was significantly increased in aluminum‐treated rabbits compared with controls. Furthermore, Western blot analysis indicated that the 20S proteasome degraded non‐phosphorylated high molecular weight neurofilament (neurofilament‐H) protein in vitro. These results suggest that aluminum does not inhibit 20S proteasome activity, and the 20S proteasome degrades neurofilament‐H protein. We propose that abnormal aggregation of phosphorylated neurofilaments is induced directly by aluminum, and is not induced by the proteasome inhibition in the aluminum‐treated rabbits. Proteasome activation might be involved in intracellular proteolysis, especially in the earlier stages of motor neuron degeneration in aluminum‐treated rabbits.