Spinal cord tau pathology in cervical spondylotic myelopathy

We conducted an immunohistochemical and ultrastructural examination of the spinal cords from 11 cases of cervical spondylotic myelopathy (CSM), together with those from 11 age- and sex-matched control subjects. Immunostaining with AT8 antibody revealed various numbers of tau-positive neuropil thread-like structures (NTSs), often demonstrating a conspicuous astrocytic foot-like perivascular or subpial arrangement, and glial cells with short and thick processes, so-called thorn-shaped astrocytes (TSAs), in the affected cervical cords in 8 of the 11 CSM cases (73%). A number of tau-positive neuronal cytoplasmic pretangles/tangles were also found in the gray matter in all the CSM cases (100%). No such astrocytic or neuronal tau lesions were found in the control subjects. The tau deposited in the NTSs and TSAs was predominantly 4-repeat tau, whereas the neuronal cytoplasmic pretangles/tangles contained both 3-repeat and 4-repeat tau. Ultrastructurally, paired helical filaments about 20 nm wide, together with glial filaments, were detected occasionally in the astrocytic processes. In conclusion, the present findings indicate that astrocytic and neuronal tau lesions appear in the affected cervical cord during the disease process of CSM.     

Three-dimensional structure of Alzheimer's neurofibrillary tangles of the aged human brain revealed by the quick-freeze,deep-etch and replica method

Summary The three-dimensional structure of Alzheimer's neurofibrillary tangles in the pyramidal cells of the hippocampus and in the nerve cells of the parahippocampal gyrus was examined by the quick-freeze, deep-etch and replica method. The tangles consisted of either parallel bundles of or randomly arranged paired helical filaments (PHF), occupying the perikaryotic cytoplasm and extending to the dendritic processes. On the stereophotographs the PHF, measuring 28 to 36 nm in width, had two component filaments of 14 to 18 nm in diameter which were coiled anti-clockwise (left-handed) around each other with periodicity of 70 to 90 nm. The PHF in compact parallel bundles were cross-linked to each other with thin filaments, of about 6 nm in diameter, at relatively regular intervals. Randomly arranged PHF had no cross-bridges or side arms. Straight-type tangles of about 24 nm in diameter were rarely found in the dendritic processes. There were no discernible differences between the PHF of the patients with senile dementia of Alzheimer type and those of nondemented brains.     

多层螺旋CT对胰腺癌转移淋巴结的诊断能力初步分析

目的:分析多层螺旋CT对胰腺癌转移淋巴结的诊断能力。方法:自2005年11月～2007年3月对87例临床疑诊为胰腺肿瘤的患者行多层螺旋CT薄层扫描,根据三维重建影像学结果确定腹部淋巴结肿大情况;17例行胰腺肿瘤根治手术,其中13例确诊为胰腺腺癌;切除标本由病理科医师确定淋巴结位置及是否转移,将影像学数据与病理结果对照分析。结果:按照外形特征及淋巴结位置,CT图像中共有41枚淋巴结可与病理结果对应,其中16枚(39.0%)转移阳性,短轴直径与非转移组淋巴结比较无统计意义(P=0.27)。分别以淋巴结短轴直径大于3mm、10mm及淋巴结长短轴直径比小于2为淋巴结转移阳性诊断标准,敏感度分别为93.8%、18.8%及50%,特异度分别为40%、88%及72%,阳性预测值分别为38.5%、50%及53.3%,阴性预测值分别为50%、62.9%及69.2%,准确度分别为39%、61%及63.4%。结论:使用多层螺旋CT以适当标准判断胰腺癌淋巴结有无转移,可以获得较高的敏感度或特异度,为选择恰当的治疗方案提供依据。     

胃肠道螺旋CT仿真内窥镜检查及临床应用评价

目的：探讨胃肠道螺旋CT仿真内窥镜检查方法及临床应用评价并与纤维电子内窥镜相比较。方法：通过对39例病人进行螺旋CT仿真内窥镜检查，采用实时螺旋扫描，GEAW4．0工作站后处理，设定CT阈值和进行图像切割，分别获得胃肠道的仿真内窥镜及立体剖面等3D图像，并与纤维电子内窥镜图像相比较。结果：螺旋CT仿真内窥镜对于胃肠道腔内结构显示与纤维电子内窥镜近似，在观察胃肠道腔外情况如：有无侵犯和转移等方面，优于纤维电子内窥镜。结论：胃肠道螺旋CT仿真内窥镜检查具有无痛、无创、快速、准确的优点，临床应用广泛。与纤维电子内窥镜检查是相辅相成的，是CT横断面图像的重要补充。     

Induction of epitopes associated with neurofibrillary tangles in clonal mouse neuroblastoma (S20Y) cells

Summary Accumulation of paired helical filaments (PHF) in neurofibrillary tangles is a key neuropathological hallmark in Alzheimer's disease (AD). To date, PHF have been found primarily in humans. Cultured murine cholinergic neuroblastoma (S20Y) cells, following exposure to a serum-free medium or a differentiation medium, developed immunoreactivity to anti-PHF antibodies, and to the Alz-50 by immunocytochemical and immunoblot analyses. Electron microscopic examination revealed abundant fascicles of 10-nm filaments coursing tortuously amongst organelles, such as mitochondria, endoplasmic reticulum and dense-core vesicles, in perikarya and in neuritic extensions. However, subcellular structures identical or similar to PHF could not be found in these non-human cells. This convenient cell culture model may prove to be useful for studying certain aspects of the mechanisms underlying the abnormal cytoskeletal alterations which are characteristic of AD and related neurodegenerative disorders.Supported by grants from the Overbrook Foundation, the Will Rogers Institute, the Dr. I. Fund Foundation, the Winifred Masterson Burke Relief Foundation, the Alzheimer's Disease Research Program of the American Health Assistance Foundation and the National Institute of Aging (AG03853)     

螺旋CT髋关节骨折三维成像技术的应用

目的 探讨螺旋CT髋关节三维成像技术的临床应用。方法 将76例髋关节外伤患者行螺旋CT三维成像，层厚2—5mm，重建间隔1．3mm，1．7mm，函数30，扫描范围包括全骨盆。结果 髋臼粉碎性骨折并碎骨块分离16例，全骨盆多处骨折并错位21例，股骨粗隆纵型骨折17例，股骨头粉碎性骨折22例，全部病例均获得较高质量的三维图像。结论 髋关节骨折行螺旋CT三维成像，能从不同的方向不同角度来立体观察骨折移位，髋臼损伤情况及髋关节脱位程度，对患者术前制定手术方案有较大帮助。     

螺旋CT多平面重建诊断输尿管结石的临床价值

目的 :探讨螺旋CT扫描结合多平面重建 (MPR)在输尿管结石诊断中的应用价值。材料和方法 :对 42例输尿管结石的患者行螺旋CT扫描并行多平面重建 (MPR) ,其中 4例行增强延时扫描。结果 :CT确诊输尿管结石 95 .3 % ( 4 0 /4 2 ) ;MPR图像质量分为好、较好、差 ,分别为 66.7% ( 2 8/4 2 )、2 3 .8% ( 10 /4 2 )、9.5 % ( 4 /4 2 )。结论 :螺旋CT结合MPR可全面、立体、直观地显示输尿管结石及梗阻扩张的程度 ,在诊断和鉴别诊断方面具有重要的临床价值。     

螺旋CT三维重建诊断上颌埋伏牙的临床价值

目的:探讨螺旋CT三维(3D)重建技术对上颌埋伏牙诊断中的临床应用价值.材料和方法:41例牙齿正畸的患者行螺旋CT轴位扫描,其中上颌埋伏牙20例,男13例,女7例.年龄8～18岁,平均12.5岁.对CT扫描采集的信息利用3D软件行最大密度(MIP)和多层面重建(MPR)二种方式的图象重建.结果:螺旋CT三维重建能清楚显示牙齿形态.其中20例共有27颗上颌埋伏牙,可显示其异常结构,埋伏牙与牙列的关系,位于牙列唇侧或腭侧.结论:螺旋CT三维重建是一种能展示牙齿立体形态影像的新技术.轴位图像、MPR和MIP联合应用能立体、直观、多方位提供临床医师所需信息,有利于治疗方案的选择.     

多层螺旋CT对中耳及内耳结构的三维立体重建

目的探讨多层螺旋CT对听神经瘤患者中耳、内耳立体影像的术前重建。方法利用多层螺旋CT对8例自愿者进行了扫描及中耳、内耳结构的立体重建。结果扫描及重建的速度快,重建出清晰的中耳、内耳的结构。结论多层螺旋CT的容积重建技术可以清楚地显示听小骨、内听道神经及膜迷路。