慢性压迫性脊髓损伤细胞凋亡的实验研究

目的：观察慢性压迫性脊髓损伤的细胞凋亡现象,方法：45只2个月龄Wistar大鼠,置入后路渐进压迫装置,根据脊髓压迫程度分为轻,中,重3组,应用Feulgen染色,末端脱氧核苷酸转移酶介导生物素化dUTP缺口末端标记（TUNEL）技术,观察不同和蔼慢必压迫性脊髓损伤后各种细胞凋亡的特点,结果：不同程度损伤直接受压段中,中度损伤的凋亡现象是了为显著,与轻度,重度损伤的凋亡率比较,差异有显才性产意义（P＜0．01）,凋亡细胞主要分布在白质纵向传导束上髓的区域,主要为少突胶质细胞,神经元存在少量凋亡现象,分布在III－IX板层,主要在后角,结论：细胞凋亡是慢性脊髓损继发病理变化的重要级成部分,神经元和胶质细胞凋亡是损伤后细胞死亡的主要原因之一,少突胶质细胞凋亡可能是白质脱髓鞘的主要原因。     

大鼠脊髓缺血再灌注损伤中Ire1α、caspase-12的表达与细胞凋亡

目的 观察在大鼠脊髓缺血再灌注损伤过程中Ire1α与caspase-12的表达变化规律及其与神经细胞凋亡的关系. 方法 健康成年SD大鼠55只,用随机数字表法分为2组:(1)脊髓压迫缺血再灌注组(手术组,50只大鼠),每个时相点10只,采用自制压迫装置制备脊髓压迫缺血再灌注模型;(2)假手术对照组(手术组,5只大鼠),只做全椎板切除不做脊髓压迫.用TUNEL、免疫组化、Western blot和免疫荧光标记等方法 ,分别于缺血再灌注后1,4,8,16和24 h检测压迫段脊髓组织中细胞凋亡以及lre1α,caspase-12的表达变化情况. 结果 细胞凋亡数量随着缺血再灌注时间的延长而增加.手术组Ire1α、caspase-12的阳性细胞数及蛋白量于再灌注1 h开始增加,16 h达峰值,24 h开始减少,但仍然高于假手术对照组(P＜0.05). 结论 Ire1α与caspase-12共同参与了内质网应激介导的神经细胞凋亡.     

骨髓间充质干细胞移植促进脊髓损伤修复的机制

目的 研究骨髓间充质干细胞(BMSCs)移植对损伤脊髓神经功能恢复的影响及其机制.方法 采用纽约大学脊髓重物坠落仪制作大鼠脊髓损伤模型.脊髓损伤后7d,在损伤中心周围移植BMSCs( BMSCs组)或注射PBS( PBS组).采用BBB评分评价大鼠脊髓功能.测定脊髓空洞体积,透射电镜观察脊髓损伤中心轴突的数量.采用绿色荧光蛋白(GFP)转基因大鼠的BMSCs示踪移植细胞,观察BMSCs移植后在脊髓中的存活及向神经细胞分化的情况.采用脊髓埋管模型,研究BMSCs移植对损伤脊髓轴突再生的影响.结果 BMSCs组BBB评分显著高于PBS组,而其脊髓空洞体积明显小于PBS组.电镜下可见,在脊髓损伤中心BMSCs组的轴突数量明显多于PBS组.细胞移植后4周,在脊髓损伤中心周围可见大量BMSCs - GFP细胞.免疫荧光染色结果表明,脊髓移植的BMSCs并不表达神经元、星形胶质细胞和少突胶质细胞的表面标志性蛋白.脊髓埋管实验发现,在种有BMSCs的导管内可见有NF阳性的神经纤维的长入,而未种有BMSCs组的导管内未见神经纤维的生长.结论 脊髓损伤后进行BMSCs移植可促进损伤脊髓功能的恢复,其机制与BMSCs移植促进神经元轴突再生的作用有关.     

脊髓损伤的细胞凋亡及其调控

脊髓损伤后 ,除神经细胞坏死外 ,还存在细胞凋亡 ,并在继发性脊髓损伤中起重要作用。笔者对近年来脊髓损伤后细胞凋亡及其分子调控机制作如下综述。一、细胞凋亡在继发性脊髓损伤中起重要作用脊髓损伤包括原发性损伤和继发性损伤 ,而神经细胞的凋亡是继发性脊髓损伤的重要组成部分。在不同脊髓损伤模型中的许多研究证实 ,继发性脊髓损伤广泛存在着神经细胞凋亡[1～ 1 0 ] 。Ｌｉ等[1 ,4] 观察大鼠脊髓压迫损伤后 4～ 9ｄ ,在损伤部位 (Ｔ8,9)及相邻节段 (Ｔ7、Ｔ1 0 )白质有大量的胶质细胞凋亡 ,细胞主要是少突胶质细胞 ,而灰质的神经元不表…     

少突胶质前体细胞移植对大鼠脊髓损伤神经功能恢复的影响

目的 研究少突胶质前体细胞移植对大鼠脊髓损伤神经功能恢复的影响.方法 采用Allen's打击法制作大鼠脊髓损伤(T10)模型.96只SD大鼠随机分为移植组、对照组、单纯损伤组及假手术组,每组24只.脊髓损伤后第7天时移植组进行少突胶质前体细胞移植治疗,对照组给予等量生理盐水,单纯损伤组未予任何治疗.通过运动功能评分及运动诱发电位、体感诱发电位检测评价少突胶质前体细胞移植对神经功能恢复的影响.结果 脊髓损伤后大鼠脊神经功能明显障碍,运动功能评分、运动诱发电位及体感诱发电位检测结果明显低于假手术组.随伤后时间延长,脊髓损伤大鼠神经功能均有不同程度的恢复,但运动功能评分、运动诱发电位及体感诱发电位检测结果显示,少突胶质前体细胞移植治疗组大鼠的神经功能恢复情况明显优于对照组.结论 少突胶质前体细胞移植治疗能够促进大鼠脊髓损伤神经功能的恢复.     

慢性压迫性脊髓损伤后神经前体细胞的增殖情况

目的　通过分析成年大鼠慢性压迫性脊髓损伤后及减压后巢蛋白表达的变化 ,探讨神经前体细胞的增殖。　方法　选用健康Wistar大鼠 5 0只 ,体重 2 80～ 32 0g。制备慢性压迫性脊髓中度、重度损伤及重度压迫损伤减压后 3,10d模型 ,自距压迫边缘至 5mm段脊髓组织切片。正常成年健康大鼠作为正常对照组。巢蛋白、胶质纤维酸性蛋白采用免疫组织化学染色 ,计算机图像分析仪定量分析 ,观察神经前体细胞的增殖情况。　结果　成年大鼠慢性压迫性脊髓中、重度损伤及重度压迫损伤减压后 3d ,巢蛋白在白质、灰质及脊髓中央管的室管膜细胞和减压后 10d组白质中均有明显表达 (P <0 .0 5 ) ,以重度压迫组最为显著 (P <0 .0 1)。减压后 10d组灰质与正常对照组比较 ,差异无显著性意义 (P >0 .0 5 )。与正常对照组相比 ,各损伤组脊髓内胶质纤维酸性蛋白表达增强 ;胶质纤维酸性蛋白阳性细胞数目增多 ,胞体肥大 ,突起增粗、增长。　结论　成年大鼠慢性压迫性脊髓损伤及减压后早期存在神经前体细胞增殖。星形胶质细胞参与神经前体细胞的增殖与迁移 ,对脊髓具有重要的营养修复作用。     

人脑少突胶质细胞的培养与鉴定

少突胶质细胞是中枢神经的成髓鞘神经胶质细胞，它包绕神经纤维的轴突形成髓鞘，对轴突正常的电传导功能有重要作用。将少突胶质细胞移植人髓鞘形成障碍或脱髓鞘的中枢神经系统内，可揭示髓鞘形成和再生机制。由于体外培养的少突胶质细胞与其在体内的特性相关,因此通过体外培养研究可了解少突胶质细胞的存活、增殖、分化和发育过程中的细胞生物学变化。然而中枢神经系统具有细胞多样性，它包括神经元、星形胶质细胞、少突胶质细胞和小胶质细胞，所以必须对少突胶质细胞进行体外纯化。     

银杏叶提取物对大鼠脊髓损伤后神经细胞凋亡和一氧化氮合酶表达的影响

目的 探讨银杏叶提取物(extract of Ginkgo biloba,Egb)对脊髓损伤后神经细胞的保护作用及其机制.方法 雌性SD大鼠48只,体重200～230 g,用随机数字表法把大鼠分为等渗盐水组(NS组)24只,银杏叶提取物组(Egb组)24只.在T9椎板水平半切脊髓.术后NS组大鼠每天给予2 ml等渗盐水灌胃,EGb761组大鼠每天给予2 ml(20mg)Egb灌胃.分别于术后1,7,14,21 d取材,行髓鞘染色、焦油紫染色、诱生型一氧化氮合酶(iNOS)免疫组化和TUNEL法标记凋亡细胞.结果 术后各时相点Egb组大鼠脊髓损伤周围邻近区脱髓鞘明显减轻,坏死囊腔明显减小,损伤侧与正常侧脊髓前角神经元数目比率明显高于NS组(P<0.05),神经细胞凋亡指数和iNOS表达阳性细胞率低于Ns组(P<0.01或P<0.05);而且,iNOS阳性细胞率与细胞凋亡指数间呈正相关(r=0.729,P<0.01).结论 Egb能减少脊髓损伤后神经细胞的凋亡,其机制可能与抑制iNOS表达有关.     

大鼠脊髓急性损伤后神经细胞的凋亡

目的 研究脊髓急性损伤后神经细胞的凋亡及其分布特点。方法 44只大鼠分为对照组（4只）和损伤组（40只）。损伤组脊髓（T8．9）经中度压迫致伤后,分别在伤后30min、2,4,8,24,48,72h和7,14,21d处死取材（每时相点鼠数＝4只）。应用HE、尼氏染色及凋亡细胞原位末端标记法对脊髓组织进行细胞检测。结果 伤后4h,损伤段及邻近段可见末端标记阳性神经细胞;伤后8h,损伤段灰质中阳性细胞数达高峰;伤后24h,白质中阳性胶质细胞数达高峰;伤后72h,相邻节段阳性细胞数达高峰。阳性细胞以白质中胶质细胞为主,主要分布于相邻手段。结论 脊髓损伤后神经细胞凋亡是继发损伤期的重要病理变化。     

雌激素影响急性大鼠脊髓损伤后细胞凋亡的相关性实验研究

目的在建立大鼠脊髓损伤模型基础上,观察不同时间点雌激素对脊髓胶质细胞,神经元凋亡的影响,以期为临床急性脊髓损伤的治疗提供理论依据。方法健康成年大鼠72只,随机分为两组,其中单纯损伤组（单纯打击损伤）36只,雌激素组（手术加雌激素）36只。脊髓损伤动物模型的制备：用自制Allen打击器25gcm致伤力撞击脊髓,制成脊髓损伤动物模型。雌激素组每日肌注雌激素（100μg／kg）直至处死,单纯损伤组仍每日肌注生理盐水0．5ml直至处死。组织切片的制备：脊髓损伤后1d、3d、5d、8d、14d、21d共6个时间段分批处死动物。4％多聚甲醛心肌灌注固定24h,切取每只大鼠T5～T13节段脊髓组织,常规制成切片,给于Bcl－2检测,TUNEL原位末端标记,检测大鼠脊髓损伤后细胞凋亡的情况。脊髓损伤后2周给予Gale评分及斜板维持试验。结果Bcl－2蛋白检测：在脊髓损伤后的第1天,脊髓组织即开始较高表达Bel－2蛋白。单纯损伤组Bcl－2高峰发生在损伤后3天,而雌激素组伤后8天达到高峰,此时Bcl－2蛋白不仅表达在神经细胞中,更多的在胶质细胞中大量表达,且此状态一直维持到伤后14天才开始下降,伤后21天仅少量表达（P〈0．05）。TUNEL原位标记检测：单纯损伤组24小时已出现不少阳性细胞,以胶质细胞为主．3～8天达到高峰,此后逐渐回落,但21天时仍有阳性细胞,应用雌激素治疗后,凋亡细胞明显减少（P〈0．05）。脊髓损伤后2周Gale评分及斜板维持率雌激素组优于单纯损伤组（P〈0．01）。结论雌激素在脊髓损伤中通过改善微循环,促进Bcl－2蛋白的表达,清除氧自由基,抗氧化作用能够抑制脊髓损伤早期神经细胞和胶质细胞的凋亡,从而减轻脊髓继发性损伤．促进脊髓神经功能的恢复。所以脊髓损伤后早期应用雌激素配合其它药物阻止神经细胞和胶质细胞的凋亡可能有助于减轻脊髓损伤的损害程度,促进脊髓神经功能的恢复,为SCI的治疗提供一个新的途径。     

Knee injury and Osteoarthritis Outcome Score (KOOS) - validation of a Swedish version

The Knee injury and Osteoarthritis Outcome Score (KOOS) is a self-administered instrument measuring outcome after knee injury at impairment, disability, and handicap level in five subscales. Reliability, validity, and responsiveness of a Swedish version was assessed in 142 patients who underwent arthroscopy because of injury to the menisci, anterior cruciate ligament, or cartilage of the knee. The clinimetric properties were found to be good and comparable to the American version of the KOOS. Comparison to the Short Form-36 and the Lysholm knee scoring scale revealed expected correlations and construct validity. Item by item, symptoms and functional limitations were compared between diagnostic groups. High responsiveness was found three months after arthroscopic partial meniscectomy for all subscales but Activities of Daily Living.     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

The role of interventional radiology in trauma

Introduction Interventional Radiology has evolved into a specialty having enormous input into the care of the traumatized patient.In all hospitals,regardless of size,the Interventional Radiologist must consider their relationships with the trauma service in order to     

The acutely limping child

Acute limping may be the result of multiple pathologies in children. The differential diagnosis varies based on the age of the child. Irrespective of age, the initial imaging work-up includes AP and frog leg radiographs of the pelvis and ultrasound; MRI may sometimes be helpful. In children less than 3 years, infections and trauma are most frequent. MRI is the imaging modality of choice when osteomyelitis is clinically suspected. Between the ages of 3 and 10 years, transient synovitis of the hip and Legg-Calvé-Perthes disease are main considerations but infection, inflammation and focal bony lesions are also considered. In children over 10 years, slipped capital femoral epiphysis also is considered.     

Diagnóstico ecográfico del neumotórax

The ultrasonographic diagnosis of pneumothorax is based on the analysis of artifacts. It is possible to confirm or rule out pneumothorax by combining the following signs: lung sliding, the A and B lines, and the lung point. One fundamental advantage of lung ultrasonography is its easy access in any critical situation, especially in patients in the intensive care unit. For this reason, chest ultrasonography can be used as an alternative to plain-film X-rays and computed tomography in critical patients and in patients with normal plain films in whom pneumothorax is strongly suspected, as well as to evaluate the extent of the pneumothorax and monitor its evolution.     

Carbohydrate Supplementation during Exercise: Does It Help? How Much is Too Much?

KEY POINTS· Carbohydrate intake during exercise can delay the onset of fatigue and improve performance of prolonged exercise as well as exercise of shorter duration and greater intensity (e.g., continuous exercise lasting about 1h and intermittent high-intensity exercise), but the mechanisms by which performance is improved are different.