胎鼠神经干细胞局部注射移植大鼠高位脊髓损伤缺损处:体感及运动诱发电位与后肢运动功能评价

背景:如何促进脊髓损伤后的神经再生和功能恢复始终是医学界一大难题,胚胎神经干细胞有利于神经元的存活,并能促进轴突再生.目的:观察胚胎鼠神经干细胞局部注射移植治疗高位脊髓损伤大鼠的可行性,以神经电生理及后肢运动功能评分评价其效果.设计、时间及地点:细胞学体内实验,于2007-06/2008-06在哈尔滨医科大学动物实验中心完成.材料:健康成年雌性SD大鼠40只,随机分为生理盐水组、细胞移植组,20只/组.另取孕14 d的SD大鼠5只用于制备胚胎神经干细胞.方法:生理盐水组、细胞移植组大鼠均建立高位脊髓损伤模型,取双侧第8-10对肋间神经各2 cm,交叉植入脊髓缺损处(近端白质与远端灰质、远端白质与近端灰质),细胞移植组局部注射鼠胚胎神经干细胞2×10~6个,生理盐水组局部注射等量无菌生理盐水.主要观察指标:通过体感诱发电位和运动诱发电位的检测,观察神经电生理恢复情况;通过BDA顺行神经示踪,观察运动传导束恢复情况:BBB后肢运动功能评分结果.结果:细胞移植组大鼠体感诱发电位及运动诱发电位的潜伏期、波幅明显优于生理盐水组(P<0.01);细胞移植组大鼠在损伤区有较多BDA标记阳性神经纤维通过,而生理盐水组未见BDA标记阳性神经纤维;细胞移植组大鼠BBB后肢运动功能评分较生理盐水组明显提高(P<0.01).结论:胎鼠神经干细胞局部注射可以较好地恢复高位脊髓损伤后的神经电生理及后肢运动功能.     

组织工程化干细胞移植治疗大鼠急性脊髓损伤的研究

目的：探讨自体骨髓间充质干细胞（BMSCs）移植对脊髓损伤（SCI）大鼠功能恢复的影响。方法：54只成年Wistar大鼠随机分成实验组（干细胞移植组）、DMEM组、空白对照组。用按 Bregman 法方法制作脊髓损伤模型。7d后干细胞移植组注入经体外传代培养诱导的骨髓间充质干细胞悬液,DMEM组在脊髓损伤处注入DMEM培养液,空白对照组只做损伤模型不做任何处理。处理后第1、4、8、12 周分别对两组大鼠进行动物BBB评分、斜板试验、后肢运动功能检测和运动诱发电位(MEP)检测。动物处死后做组织学观察。结果：处理后1 周时,两组动物脊髓神经功能均无明显恢复;第4、8、12周时移植组大鼠运动诱发电位潜伏期和波幅明显恢复, 斜板试验角度和BBB 评分及后肢运动功能检测评分均高于对照组大鼠（P<0.01）;DMEM组与对照组间P>0.05。与前一时间点比较,运动诱发电位潜伏期和波幅均有明显恢复,（P<0.01）;斜板试验角度和BBB 评分以及后肢运动功能检测评分在第8周与第12周间无显著差异（P>0.05）。结论：BMSCs移植可以促进大鼠损伤脊髓功能的恢复。     

高压氧联合神经干细胞移植治疗大鼠脊髓损伤

背景:单纯神经干细胞移植已应用于对受损脊髓组织的修复。目的:以神经干细胞移植同时应用高压氧治疗大鼠脊髓损伤,观察联合作用对脊髓损伤大鼠运动功能恢复的影响。方法:雌性SD大鼠60只,以半切法制成胸段脊髓半横断大鼠模型。随机分成单纯损伤组、神经干细胞移植组及高压氧治疗组,每组20只。伤后第4周取材行病理切片苏木精-伊红染色及BrdU免疫组织化学染色,第8周取材行辣根过氧化物酶示踪,透射电镜观察轴突的再生情况,通过体感诱发电位观察神经电生理恢复情况。造模后1,2,4,6,8周进行BBB评分和斜板实验等运动功能检测。结果与结论:观察伤后4周病理切片,单纯损伤组未见神经轴索通过,神经干细胞移植组可见少量神经轴索样结构,高压氧治疗组可见较多神经轴索样结构。BrdU的阳性细胞数及辣根过氧化物酶阳性神经纤维数,高压氧治疗组最多,神经干细胞移植组次之,单纯损伤组最少,且各组之间差异有显著性意义(P<0.05)。透射电镜下神经干细胞移植组、高压氧治疗组正中横断面可见新生的无髓及有髓神经纤维。高压氧治疗组大鼠体感诱发电位的潜伏期短于神经干细胞移植组,波幅高于神经干细胞移植组(P<0.05),明显优于单纯损伤组(P<0.01)。伤后4周神经干细胞移植组、高压氧治疗组大鼠后肢运动功能均有较明显恢复,高压氧治疗组较神经干细胞移植组恢复快(P<0.05);单纯损伤组亦有所恢复,但程度较轻。提示神经干细胞移植对于脊髓损伤大鼠后肢功能的恢复有促进作用,联合应用高压氧有协同效果。     

基质细胞衍生因子-1对神经干细胞移植治疗脊髓损伤大鼠疗效的影响

目的观察基质细胞衍生因子-1(SDF-1)对神经干细胞移植治疗脊髓损伤大鼠疗效的影响。 方法共选取96只成年健康雄性SD大鼠,应用改良Allen′s打击法制成脊髓损伤大鼠模型,采用随机数字表法将其分为4组,分别是A组（于制模后7d时给予磷酸盐缓冲液注射）、B组（于制模后7d时给予神经干细胞移植）、C组（于制模后7d时联合给予SDF-1注射及神经干细胞移植）及D组（于制模后7d时给予AMD3100及神经干细胞移植）。于制模后7d、14d、21d及28d时分别采用BBB运动功能评分对各组大鼠后肢运动功能进行评定,并于上述时间点对各组大鼠受损脊髓进行HE染色及CM-Dil荧光观察。 结果在制模后14d、21d及28d时B组及C组大鼠受损脊髓区均能见到荧光标记阳性细胞聚集,上述时间点C组脊髓损伤区域阳性细胞数量［分别为（27.4±4.7）个、（20.4±5.2）个、（18.3±3.9）个］较B组细胞数量［分别为（23.6±3.7）个、（18.9±5.6）个、（15.2±4.3）个］显著增多（P<0.05）。在制模后14d、21d及28d时B组BBB运动功能评分［分别为（4.18±0.87）分、（6.18±1.25）分、（9.27±0.91）分］及C组BBB运动功能评分［分别为（5.09±1.30）分、（8.18±0.75）分、（11.82±0.87）分］均较A组及D组显著改善（P<0.05）,并且C组大鼠上述时间点BBB运动功能评分亦显著优于B组水平（P<0.05）。 结论移植的神经干细胞能向大鼠受损脊髓部位迁移、存活并分化,能促进大鼠后肢运动功能恢复;SDF-1能诱导神经干细胞增殖并向脊髓损伤部位迁移,CXCR4受体阻断剂AMD3100能显著阻断神经干细胞向大鼠受损脊髓部位迁移。     

神经干细胞-施万细胞-聚乳酸-羟基乙酸共聚物支架移植对脊髓损伤大鼠的影响

目的探讨种植神经干细胞(NSCs)与施万细胞(SCs)的聚乳酸-羟基乙酸共聚物(PLGA)支架移植促进脊髓损伤大鼠神经功能恢复的作用及机制。方法体外培养NSCs 和SCs,以PLGA 为支架移植入大鼠T8 半横断脊髓损伤处。实验动物随机分为PLGA组、PLGA+NSCs 组和PLGA+NSCs+SCs 组。术前和术后进行皮层运动诱发电位(CMEPs)检查及BBB评分;然后在同侧或对侧进行T6再次半横断,并进行CMEPs 检测及BBB 评分。结果CMEPs 的恢复率及波幅在PLGA+NSCs+SCs 组最高。移植后,大鼠BBB 评分逐渐改善;在移植后第2 周及以后,PLGA+NSCs 组和PLGA+NSCs+SCs 组的BBB 评分显著高于PLGA 组(P<0.001)。同侧再次半横断后,CMEPs 消失, BBB 评分快速恢复;对侧再次半横断后,大鼠双下肢完全瘫痪。结论种植NSCs 和SCs 的PLGA支架移植有利于脊髓损伤功能重建,再生轴突可能形成了功能性连接;但是同侧再生轴突对脊髓功能的恢复作用有限。     

自体富血小板血浆对大鼠脊髓损伤后神经功能的影响

目的 研究自体富血小板血浆对大鼠脊髓损伤后神经功能恢复的影响。方法 SD大鼠30只,随机分为PRP组(A组)和对照组(B组)各15只。采用改良Nystr?m法后路压迫大鼠胸段脊髓模型,A组予自体富血小板血浆灌注于损伤脊髓处,B组予自体血浆灌注于损伤脊髓处。术后第3、7、14天采用斜板试验和BBB运动功能评分观察大鼠后肢运动功能恢复情况、检测体感诱发单位(SSEP)检测神经传导功能。结果 大鼠脊髓损伤后7、14天,A组后肢运动功能评分明显高于B组,两者间差别有统计学意义(p<0.05)。SSEP潜伏期及波幅值变化：术后14天A组潜伏期12.37±1.689ms、波幅0.54±0.056mv；B组潜伏期14.14±1.553ms、波幅0.32±0.031mv,两组差别有统计学意义(P<0.05)。结论 自体富血小板血浆能促进大鼠神经功能的早期恢复。     

骨髓间质干细胞源性神经元样细胞与控释神经营养因子移植治疗猴脊髓损伤:电生理评价

背景:临床研究表明诱发电位监测能准确监测脊髓的损伤,因此通过对电生理的监测来评估干细胞移植治疗脊髓损伤的效果具有重要意义.目的:通过电牛理监测评估骨髓间质干细胞源件神经元样细胞与控释神经营养因子移植治疗猴脊髓损伤的疗效.设计、时间及地点:随机对照动物实验,于2004-06/2005-11在中山大学附属二院骨外科实验室完成.材料:健康雄性恒河猴8只,随机分为移植组、模型组,4只,组.方法:两组猴均建立急性脊髓损伤模型.造模后第10天,取体外分离培养的猴骨髓间质干细胞源性神经元样细胞3.0×106cells/kg,与含1 μg胶质细胞源性神经营养因子的控释生物材料用200 μL PBS制成悬液,分5点沣射到移植组脊髓损伤部位;模型组同法给予等量磷酸盐缓冲液.主要观察指标:皮质体感诱发电位检查结果,运动诱发电位检查结果,行为学Tarlov分级.结果:①造模前两组动物均检测到正常皮质体感诱发电位信号,造模后两组动物皮质体感诱发电位波幅消失.移植后四五个月,移植组3只恒河猴皮质体感诱发电位波幅有明显恢复,但波幅仍明显低于造模前(P＜0.01),且潜伏期也延迟(P＜0.01);模型组动物末见有皮质体感诱发电位波幅恢复.②造模后两组动物运动诱发电位缺失.移植后4～5个月,移植组运动诱发电位波型有轻微恢复,但潜时期平均延长3.1 ms,波幅下降超过50%;模型组运动诱发电位仍然缺失.③移植后四五个月,移植组行为学Tadov分级为1或2级,模型组为0级.结论:电牛理评估结果表明,骨髓间质干细胞源性神经元样细胞与胶质细胞源性神经营养因子控释材料联合移植可以促进损伤脊髓的一定程度恢复.     

减重步行训练对脊髓损伤大鼠干细胞移植后神经细胞诱导分化的影响

目的探讨骨髓间充质干细胞(BMSCs）移植联合减重步行训练对脊髓损伤(SCI)大鼠神经功能恢复的影响。 方法选取Sprague-Dawley(SD)雄性大鼠,采用改良的简易打击装置制作T11完全性SCI模型,将SCI造模成功的40只大鼠根据干预方法的不同按随机数字表法分为干细胞移植组、减重步行训练组、联合治疗组(干细胞移植联合减重步行训练)和对照组(不做任何干预处理),每组10只大鼠。SCI手术1周后,对干细胞移植组及联合治疗组大鼠进行干细胞移植。取传至第3代的BMSCs,移植前1天用5-乙炔基-2′脱氧尿嘧啶核苷(Edu)标记,移植后减重步行训练组及联合治疗组进行减重步行训练,其余2组进行自由活动。分别于SCI后第1、2、3、4和5周,通过BBB(Basso-Beattie-Bresnahan)运动功能评分来判断运动功能恢复情况;于SCI第5周,应用免疫组化染色及免疫荧光染色的方法检测神经特异性标志物神经元特异性烯醇化酶(NSE)、微管相关蛋白(MAP-1β)及波形蛋白(VIM)的阳性表达,观察移植细胞的存活、分化及损伤部位神经纤维的恢复情况。 结果①BBB运动功能评分显示,SCI手术第2周联合治疗组BBB评分为［(6.60±0.97)］分,明显高于其余3组;干细胞移植组和减重步行训练组的BBB运动功能评分分别为［(5.00±0.67)和(4.80±0.63)］分,均高于对照组,但组间差异无统计学意义(P&rt;0.05)。术后第3周,干细胞移植组的BBB运动功评分为［(8.00±0.67)］分,高于减重步行训练组［(6.80±0.79)分］,组间差异有统计学意义(P<0.05)。②免疫组化染色法显示,有不同程度的神经特异性标志物(NSE、MAP-1β、VIM)阳性细胞充填于各组大鼠的SCI组织中,通过半定量分析法读取各组大鼠脊髓组织中阳性表达半定量值,联合治疗组分别为［(4.72±0.19)、(4.50±0.22)和(4.62±0.27)］分,明显高于其余3组,组间差异有统计学意义(P<0.05)。③免疫荧光染色法显示,联合治疗组神经特异性标志物(NSE、MAP-1β、VIM)荧光表达明显强于其余3组,同时可见明显的神经纤维增生和分化。 结论干细胞移植结合减重步行训练可有效促进SCI大鼠神经功能的恢复,且效果明显优于单纯干细胞移植组和减重步行训练组。     

乙交酯-丙交酯共聚物-细胞复合体移植治疗脊髓损伤

目的:观察神经干细胞、许旺细胞和组织工程支架材料乙交酯-丙交酯共聚物于大鼠髓内共移植后的生物相容性,及其对大鼠损伤脊髓形态和功能的修复作用。方法:实验于2005-05/2006-09在首都医科大学附属北京市神经外科研究所损伤修复实验室完成。①实验材料:健康成年雌性Wistar大鼠36只,随机数字表法分为单纯支架组、神经干细胞 支架复合体组、神经干细胞 许旺细胞 支架复合体组,12只/组。乙交酯-丙交酯共聚物由中科院化学研究所医用高分子材料中心提供。②实验方法:各组大鼠均建立脊髓T9半横断损伤模型。神经干细胞 许旺细胞 支架复合体组取2×1010L-1的许旺细胞、神经干细胞各10μL接种于乙交酯-丙交酯共聚物支架内,神经干细胞 支架复合体组取2×1010L-1的神经干细胞10μL接种于乙交酯-丙交酯共聚物支架内,单纯支架组取10μLDMEM培养液置于乙交酯-丙交酯共聚物支架内,于脊髓缺损处分别植入对应的复合物。③实验评估:应用电镜观察乙交酯-丙交酯共聚物支架的降解及轴突的再生状况;应用BBB评分和电生理技术检测大鼠脊髓功能性的恢复情况。结果:36只Wistar大鼠均进入结果分析。①行为学观察结果:移植术后4,12周,神经干细胞 支架复合体组、神经干细胞 许旺细胞 支架复合体组大鼠的后肢运动功能BBB评分均好于单纯支架组(P<0.01),其中神经干细胞 许旺细胞 支架复合体组尤为明显。②神经电生理检查结果:在脊髓半横断损伤后即刻,所有动物的体感诱发电位和运动诱发电位波幅都明显减低甚至消失。移植术后4周,神经干细胞 支架复合体组、神经干细胞 许旺细胞 支架复合体组大鼠的体感诱发电位和运动诱发电位波幅均有所恢复;至移植术后12周恢复明显。单纯支架组移植术后4,12周体感诱发电位和运动诱发电位波幅无明显变化。③电镜观察结果:扫描电镜下,随着时间的延长各组植入的乙交酯-丙交酯共聚物逐渐降解。透射电镜下,各组植入材料正中横断面可见新生的无髓及有髓神经纤维,至12周时神经干细胞 许旺细胞 支架复合体组最明显。结论:乙交酯-丙交酯共聚物在大鼠损伤的脊髓内具有良好的生物相容性;其与神经干细胞、许旺细胞共移植能够明显促进脊髓半横断损伤大鼠的脊髓轴突再生,并改善肢体的运动功能。     

骨髓间充质干细胞静脉移植治疗大鼠脊髓损伤

背景:干细胞移植可以重建中枢神经系统的结构和功能,近年来引起了广泛的关注。目的:尾静脉移植骨髓间充质干细胞观察其对大鼠脊髓损伤修复的影响并探讨其机制。方法:密度梯度离心法结合贴壁筛选法分离骨髓间充质干细胞。将成年雌性Wistar大鼠以动脉瘤夹钳夹法制备大鼠脊髓损伤模型后随机分为细胞移植组和对照组,分别干预。结果与结论:细胞移植组大鼠BBB后肢功能评分恢复优于对照组(P<0.05)。自损伤后第30天开始,细胞移植组大鼠运动诱发电位潜伏期及体感诱发电位P1波潜伏期的恢复均优于对照组(P<0.05),并持续至实验结束。细胞移植组大鼠脊髓内在损伤中心及头、尾端距离脊髓损伤中心1cm处均可见阳性细胞。说明尾静脉注射移植骨髓间充质干细胞可以促进脊髓损伤大鼠神经功能恢复,其机制可能与移植细胞迁移到损伤部位,分化为神经元样和神经胶质细胞样细胞,并分泌或促进宿主分泌神经营养因子有关。     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Modified micro-superior percutaneously-assisted total hip: early experiences & case reports

Because of the extensile nature and familiarity of the standard posterior-lateral approach to the hip, a family of "micro-posterior" approaches has been developed. This family includes the Percutaneously-Assisted Total Hip (PATH) approach, the Supercapsular (SuperCap) approach and a newer hybrid approach, the Supercapsular Percutaneously-Assisted Total Hip (SuperPATH) approach. Such approaches should ideally provide a continuum for the surgeon: from a "micro" (external rotator sparing) posterior approach, to a "mini" (external rotator sacrificing) posterior approach, to a standard posterior approach. This could keep a surgeon within his comfort zone during the learning curve of the procedure, while leaving options for complicated reconstructions for the more practiced micro-posterior surgeons. This paper details one author's experiences utilizing this combined approach, as well as permutations of this entire micro-posterior family of approaches as applied to more complex hip reconstructions.     

Structure and function of "metalloantibiotics"

Although most antibiotics do not need metal ions for their biological activities, there are a number of antibiotics that require metal ions to function properly, such as bleomycin (BLM), streptonigrin (SN), and bacitracin. The coordinated metal ions in these antibiotics play an important role in maintaining proper structure and/or function of these antibiotics. Removal of the metal ions from these antibiotics can cause changes in structure and/or function of these antibiotics. Similar to the case of "metalloproteins," these antibiotics are dubbed "metalloantibiotics" which are the title subjects of this review. Metalloantibiotics can interact with several different kinds of biomolecules, including DNA, RNA, proteins, receptors, and lipids, rendering their unique and specific bioactivities. In addition to the microbial-originated metalloantibiotics, many metalloantibiotic derivatives and metal complexes of synthetic ligands also show antibacterial, antiviral, and anti-neoplastic activities which are also briefly discussed to provide a broad sense of the term "metalloantibiotics."