胎鼠神经干细胞超顺磁性氧化铁颗粒标记移植后MRI研究

目的:探讨超顺磁性氧化铁颗粒(SPIO)标记神经干细胞的方法,以及标记细胞正常大鼠脑内移植后MR成像的方法学研究。方法:多聚左旋赖氨酸介导的SPIO标记胎鼠神经干细胞,进行台盼兰染色和普鲁士兰染色分别检测标记细胞的存活率和标记率。选取SD大鼠15只,简单随机法分为3组:第1组于大鼠右侧尾状核移植未标记的NSCs,第2组于大鼠右侧尾状核移植标记的NSCs,第3组右侧尾状核移植游离的SPIO颗粒,移植后第1、4、8周进行MRI。8周后处死大鼠,行组织切片普鲁士兰染色。结果:体外标记的神经干细胞普鲁士兰染色发现铁颗粒聚集于细胞浆内,标记率为100%;标记细胞与未标记细胞的台盼兰染色结果无显著差异。移植后MRI,第1组注射点未见低信号影;第2组注射点T2WI及GRE序列均可见类圆形低信号影;第3组大鼠注射后1周注射点可见低信号影,4周后低信号影变淡且边缘变模糊,8周后低信号影T2WI已不明显。与T2WI序列比较,GRE序列显示标记细胞更清晰,但显示范围较扩散。脑组织切片的普鲁士兰染色显示,第1组大鼠脑组织切片未见异常蓝染细胞,第2组注射点可见蓝染细胞,第3组注射点可见稍许散在蓝色颗粒状物质。结论:多聚左旋赖氨酸介导下SPIO可用于标记神经干细胞,标记细胞移植后MRI可以无创性观察移植神经干细胞的位置及分布情况。     

超顺磁性氧化铁标记大鼠骨髓基质细胞经门静脉移植MRI活体示踪的研究

目的观察1．5T场强MRI联合动物专用线圈是否可以活体示踪经门静脉移植的纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞（bone marrow stromal cells BMSCs），为介人性门静脉骨髓基质细胞移植治疗终末期肝脏疾病的研究提供进一步的依据。方法供体大鼠5只，梯度密度离心分离BMSCs，纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，体外经普鲁士蓝染色和HE染色确定细胞标记率。受体大鼠15只，分为5组，分别为对照组和纳米级超顺磁性氧化铁颗粒标记的骨髓基质细胞经门静脉移植人正常大鼠肝脏后2h、3d、7d及2周组。1．5T场强MRI联合动物专用线圈行T1W、T2W和T2＊序列扫描，观察肝脏信号改变情况，与对照组比较，并且与组织切片对照。结果纳米级超顺磁性氧化铁颗粒和脂质体转染BMSCs，细胞标记率〉95％。经门静脉移植人正常大鼠肝脏后，T2＊序列扫描显示经标记的BMSCs在肝内显示弥漫性的结节性低信号影，移植后2h到2周均可见到细胞在受体肝脏内存在，组织学切片显示信号缺失部位与铁颗粒标记细胞相一致。结论纳米级超顺磁性铁氧体颗粒标记的大鼠BMSCs经门静脉移植后可以通过1、5T场强行MRI活体示踪，为临床干细胞移植的应用提供可行的示踪方法。     

经脾移植SPIO-PLL标记的诱导后大鼠胰岛素分泌细胞及MR示踪研究

目的 超顺磁性氧化铁颗粒及多聚左旋赖氨酸复合体(SPIO-PLL)标记诱导后的大鼠胰岛素分泌细胞,移植入正常大鼠脾,应用1.5 T MR仪进行活体成像,为胰岛素分泌细咆移植后的活体示踪提供依据.材料与方法将大鼠骨髓间质干细胞(BMSCs)体外诱导成胰岛素分泌细胞,SPIO-PLL标记细胞.10只受体大鼠分二组,每组5只.将标记后的胰岛素分泌细胞(标记组)和未标记的胰岛素分泌细胞(未标记组)分别移植入脾.各组分别于移植前、移植后5天、10天、14天及21天对脾进行T1WI、T2WI、T2*WI三个序列MR扫描,观察脾信号改变情况,在T2*WI序列测量移植部位脾信噪比(SNR),与各时间点脾组织切片普鲁士蓝染色对照.结果 与移植前相比,标记组脾移植部位SNR值明显降低,差异有统计学意义(F=182.92,P<0.05),但移植后各时间点SNR值差异无统计学意义(Bonferroni法,P>0.05).未标记组脾移植前后SNR值差异无统计学意义(F=0.98,P>0.05).脾组织切片普鲁士蓝染色显示标记组染色阳性部位沿注射针道分布,与MRI信号降低区域基本一致.结论 SPIO-PLL可以有效标记诱导后大鼠胰岛素分泌细胞.临床应用型1.5 T MR仪可对经脾移植的标记细胞进行活体示踪.     

肾功能衰竭大鼠超顺磁性氧化铁标记骨髓间充质干细胞肾脏移植MR活体示踪的研究

目的应用磁性氧化铁纳米粒子和多聚左旋赖氨酸（poly-L-lysine，PLL）的偶联物Fe2O3-PLL标记大鼠骨髓间充质干细胞（MSCs），MR活体示踪经肾动脉移植入肾功能衰竭（简称肾衰）大鼠肾脏的标记细胞。方法制备Fe2O3-PLL，分离、纯化并培养大鼠骨髓MSCs，Fe2O3-PLL标记细胞，普鲁士蓝染色显示细胞内铁。肌内注射甘油所致肾衰的大鼠分为2组，分别经左肾动脉移植入标记细胞（6只）和未标记细胞（5只），移植后即刻及第1、3、5、8天应用MRI对移植细胞进行活体示踪，并与肾脏组织切片普鲁士蓝染色和HE染色对照。结果MSCs的Fe2O3-PLL标记率近100％，普鲁士蓝染色显示蓝色铁颗粒位于MSCs胞质内。标记细胞移植后肾衰大鼠肾脏皮质区信号强度明显下降，T2＊WI信号改变最明显，而肾髓质及肾盂信号较细胞移植前无明显变化，信号改变随着时间的延长逐渐减轻一直持续到移植后第8天。组织学分析见绝大多数标记细胞分布于肾皮质肾小球内，与MRI信号改变区域基本一致。未标记细胞移植后未见肾脏信号改变。结论Fe2O3-PLL可以有效标记大鼠骨髓MSCs，临床应用型1．5T磁共振仪可对经肾动脉移植入肾衰大鼠肾脏的标记细胞进行初步活体示踪。     

SHU555A标记大鼠骨髓间充质干细胞的磁敏感加权成像

目的 探讨超顺磁性氧化铁颗粒体外标记大鼠骨髓间充质干细胞(bone marrow stem cells,BMSC)后磁敏感加权成像序列显示移植细胞的可行性.方法 使用不同终浓度(7 μg/ml、14 μg/ml、28 μg/ml和56 μg/ml)的SHU555A标记大鼠骨髓间充质干细胞,标记后进行普鲁士蓝染色、细胞内铁颗粒的透射电镜观察及体外磁敏感加权序列成像,并将标记后的BMSC移植入正常大鼠脑内,移植后第1、3周和7周进行3.0T MRI磁敏感加权序列成像.结果 细胞普鲁士蓝染色及透射电镜显示铁颗粒散在分布于细胞胞质内.标记细胞的Ependoff管在SWI序列图像上呈明显低信号,且随SHU555A标记浓度的增高,标记细胞的Ependoff管信号强度在SWI序列幅值图及磁敏感加权图像上依次降低.标记后的BMSC移植入正常大鼠脑内1周后,SWI序列图像可见正常脑组织背景上团块状类圆形局限性极低信号影;移植7周后局部仍可显示低信号.结论 MRI磁敏感加权序列图像不仅可在体外明确显示SHU555A标记所致的低信号,且标记细胞移植入正常大鼠脑内最长达7周后仍可在磁敏感加权序列图像上显示.     

体外磁标记骨髓基质细胞移植治疗大鼠创伤性脑损伤的在体磁敏感加权成像研究

目的 采用磁敏感加权成像(susceptibility weighted imaging,SWI)序列在体监测超顺磁性氧化铁颗粒(su perparamagnetic iron oxide,SPIO)标记大鼠骨髓基质细胞(bone marrow stromal cells,BMSCs)在创伤性脑损伤(trau matic brain injury,TBI)模型大鼠腩内的分布及移行.材料与方法首先进行BMSCs体外培养,然后采用SPIO体外标记BMSCs;TBI采用Feeney法制作,TBI 24 h后于损伤区周围立体定向移植BMSCs,并于移植后1天、1周及3周行MR检查.结果 标记BMSCs普鲁士蓝染色显示胞质内存在较多蓝染颗粒,电镜下胞浆内可见散在分布的铁颗粒.细胞移植后MRI可见移植部位在SWI各图像上均呈团块状低信号.结论 SWI序列能够连续无创性活体示踪移植SPIO标记BMSCs在TBI模型大鼠脑内的形态和分布.     

GFP转基因胎鼠神经干细胞的体外磁标记及MRI

目的 探讨超顺磁性氧化铁颗粒(superparamagnetic iron oxide, SPIO)标记绿色荧光蛋白(green fluorescent protein, GFP)转基因胎鼠神经干细胞(neural stem cells, NSCs)后对其生物学特性的影响及标记后MR成像效果.方法 采用多聚赖氨酸PLL(0.75 μg/ml)介导SPIO(25 μg Fe/ml)的方法标记GFP转基因胎鼠NSCs,用普鲁士蓝染色观察标记后NSCs内铁,比较标记和未标记NSCs的GFP表达、活力、增殖、凋亡及多向分化能力,并对标记的NSCs行MRI.结果 普鲁士蓝染色示标记NSCs胞质内见大量蓝色颗粒.标记与未标记细胞的活力、增殖、凋亡及多向分化能力经单因素方差分析后均显示2组细胞间无统计学差异(P值均＞0.05).MRI示1×105个/0.5 ml细胞管在T2*WI中可见明显低信号改变.结论 用PLL介导SPIO标记GFP转基因胎鼠NSCs是一种可行、安全、有效的细胞内标记方法.1.5T MR仪能够在体外观察到标记后的细胞,以T2*WI序列最为敏感.     

低浓度超顺磁性氧化铁标记兔骨髓间充质干细胞的体外磁共振成像研究

目的:以浓度为25μg Fe/ml的超顺磁性氧化铁纳米粒子(SPIO)体外标记兔骨髓间充质干细胞(BMSCs),并探讨1.5 T核磁共振仪成像的特征和成像所需最低标记细胞浓度,以及在标记后1 d、1周、2周、3周、4周的信号变化特征。方法:分离、纯化、培养兔BMSCs并以25μg Fe/ml的SPIO培养液浓度标记,对标记后不同时间的细胞行普鲁士蓝染色和台盼蓝拒染后显微镜观察,并进行MR成像,测量不同序列下不同浓度标记细胞管的信号强度,以确定扫描敏感序列及成像所需最低标记细胞浓度;再测量不同细胞浓度不同时相信号强度,来观察信号强度随时间变化的规律,并进行统计学分析。结果:浓度为25μg Fe/ml的超顺磁性氧化铁纳米粒子标记BMSCs的有效率接近100%,普鲁士蓝染色见细胞浆内有大小不等的蓝染铁颗粒,且在标记后4周内细胞仍具有活力,标记后的BMSCs在T2WI、尤其是GRE(T2*WI)序列信号明显降低;并且细胞浓度越高信号降低越明显,GRE序列MR成像的最低细胞浓度为5×104/ml。当标记细胞浓度为5×104/ml时,信号在T2*WI序列的降低2周后失去统计学意义;而在细胞浓度为5×105/ml时,标记3周后,信号在T2*WI序列的降低才失去统计学意义。结论:25μg/ml铁浓度标记干细胞不仅标记效率高,而且对细胞生长及增殖活力无明显影响,标记后MR信号改变与干细胞数目及标记时间相关。     

超顺磁性氧化铁标记鼠骨髓间充质干细胞的体外MR成像研究

目的: 探讨不同浓度超顺磁性氧化铁(SPIO)颗粒标记鼠骨髓间充质干细胞(MSCs)的标记率和对细胞活力的影响,以及MR成像显示磁标记干细胞的可行性.材料和方法: 将不同浓度的SPIO-PLL复合物与培养基混合,行普鲁士蓝染色观察细胞内铁和检测细胞活力.应用1.5T MR仪,以T1WI和T2WI行磁标记干细胞成像.结果: SPIO可有效标记MSCs,标记后的铁颗粒位于细胞质内.SPIO标记的MSCs可引起T2WI信号降低,50、100、150较25μg Fe /ml的信号强度降低明显.结论: SPIO可以简便标记MSCs,并在适当浓度下对细胞活力没有影响,此技术为干细胞移植的MR活体内示踪奠定基础.     

超小超顺磁性氧化铁微粒对神经干细胞生物学活性的影响

目的应用超小超顺磁性氧化铁微粒Sinerem标记大鼠骨髓源性神经干细胞（NSCs），探讨Sinerem的安全性及合适的标记浓度。方法分离、培养大鼠骨髓源性NSCs。制备Sinerem多聚赖氨酸复合物，以不同浓度Sinerem对细胞进行标记。普鲁士蓝染色和电镜观察细胞内铁，CCK-8法检测细胞生长增殖情况，AnnexinV—PI法检测细胞凋亡及死亡情况。结果普鲁士蓝染色显示细胞质内大量铁颗粒存在，标记率在99％以上。电镜观察见Sinerem标记干细胞内含纳米铁颗粒。CCK-8法检测结果表明，25～1500μg/ml不同浓度范围的Sinerem对细胞增殖的影响差异无统计学意义。AnnexinV—PI检测结果显示，Sinerem在25～200μg/ml范围内的不同浓度对细胞凋亡和死亡的影响差异无统计学意义。结论超小超顺磁性氧化铁微粒Sinerem可以有效标记大鼠骨髓源性NSCs，可以应用25～200μg／ml浓度范围的Sinerem标记细胞。     

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 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.     

Do Balance Board Training Programs Reduce the Risk of Ankle Sprains in Athletes?

Introduction Ankle sprains are the most common musculo-skeletal injury that occurs in athletes,particularly in sports that require jumping and landing on one foot such as soccer,and basketball(1-4).These injuries often result in significant time loss from participation,long-term disability,and have a major impact on health care costs and resources(5-8).     

High Intensity Interval Training:New Insights

KEY POINTS ·High-intensity interval training(HIT)is characterized by repeated sessions of relatively brief，intermittent exercise.often performed with an“a11 out”effort or at an intensity close to that which elicits peak oxygen uptake(i.e.，≥90%of VO2 peak).     

Developmental validation of the PowerPlex(®) ESI 16 and PowerPlex(®) ESI 17 Systems: STR multiplexes for the new European standard

In response to the ENFSI and EDNAP groups’ call for new STR multiplexes for Europe, Promega^® developed a suite of four new DNA profiling kits. This paper describes the developmental validation study performed on the PowerPlex^® ESI 16 (European Standard Investigator 16) and the PowerPlex^® ESI 17 Systems. The PowerPlex^® ESI 16 System combines the 11 loci compatible with the UK National DNA Database^®, contained within the AmpFlSTR^® SGM Plus^® PCR Amplification Kit, with five additional loci: D2S441, D10S1248, D22S1045, D1S1656 and D12S391. The multiplex was designed to reduce the amplicon size of the loci found in the AmpFlSTR^® SGM Plus^® kit. This design facilitates increased robustness and amplification success for the loci used in the national DNA databases created in many countries, when analyzing degraded DNA samples. The PowerPlex^® ESI 17 System amplifies the same loci as the PowerPlex^® ESI 16 System, but with the addition of a primer pair for the SE33 locus. Tests were designed to address the developmental validation guidelines issued by the Scientific Working Group on DNA Analysis Methods (SWGDAM), and those of the DNA Advisory Board (DAB). Samples processed include DNA mixtures, PCR reactions spiked with inhibitors, a sensitivity series, and 306 United Kingdom donor samples to determine concordance with data generated with the AmpFlSTR^® SGM Plus^® kit. Allele frequencies from 242 white Caucasian samples collected in the United Kingdom are also presented. The PowerPlex^® ESI 16 and ESI 17 Systems are robust and sensitive tools, suitable for the analysis of forensic DNA samples. Full profiles were routinely observed with 62.5 pg of a fully heterozygous single source DNA template. This high level of sensitivity was found to impact on mixture analyses, where 54–86% of unique minor contributor alleles were routinely observed in a 1:19 mixture ratio. Improved sensitivity combined with the robustness afforded by smaller amplicons has substantially improved the quantity of data obtained from degraded samples, and the improved chemistry confers exceptional tolerance to high levels of laboratory prepared inhibitors.