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31.
K. Nishiyama S. Murayama Y. Nishimura K. Asayama I. Kanazawa 《Acta neuropathologica》1996,93(1):19-23
Iron accumulation in the basal ganglia and spheroid formation are pathological hallmarks of Hallervorden-Spatz disease (HS).
Since an overaccumulation of iron (iron thesaurosis) that exceeds the binding capacity of ferritin could cause oxidative damage,
we studied the possible role of oxidative stress in the pathogenesis of HS. The basal ganglia and spinal cord from patients
with HS were investigated at autopsy, using histochemistry for iron and immunohistochemistry for Cu/Zn superoxide dismutase
(SOD1), Mn superoxide dismutase (SOD2) and ferritin. SOD1-like immunoreactivity (IR), SOD2-IR and ferritin-IR occurred frequently
in spheroids observed in the basal ganglia, and associated iron accumulation indicated the possible existence of increased
oxidative stress in HS patients. Spheroids in the spinal cord showed intense SOD1-IR and SOD2-IR in HS, in sharp contrast
with the occasional weak SOD1-IR and SOD2-IR observed in spheroids from patients with amyotrophic lateral sclerosis (ALS).
Neither increased ferritin-IR nor iron accumulation were observed in spinal spheroids from HS and ALS patients. These data
may suggest that, at least in the spinal cord, SOD1-IR and SOD2-IR in spheroids in HS patients do not result from oxidative
stress directly related to iron accumulation.
Received: 15 March 1996 / Revised accepted: 15 July 1996 相似文献
32.
Shoichi Sasaki 《Neuropathology》1993,13(3):185-192
I briefly review spheroids observed in the anterior horns of the spinal cord in amyotrophic lateral sclerosis (ALS). Spheroids are argentophilic bodies more than 20 μm in diameter. Recently, some connections between the proximal axonal swellings including spheroids and the perikarya have been reported in some ALS patients with a short clinical course or mild depletion of anterior horn neurons. Most of the cell bodies directly connected with the axonal swellings appear normal, and spheroids are considered to be one of the hallmarks of the early histological changes in this disorder. Spheroids are strongly positive with anti-phosphorylated neurofilament antibody, and are also positive with calcitonin gene-related peptide and anti-peripherin antibody. Some spheroids are immunostained with anti-synaptophysin antibody and anti-ubiquitin antibody. Spheroids are not immunostained with anti-phosphorylated tau antibody, or high molecular weight microtubule associated proteins. Electron microscopically, spheroids are usually composed of densely packed accumulation of 10 nm neurofilaments with a variety of orientations, plus vesicles, dense bodies and mitochondria. When the swellings of the initial segment is relatively pronounced, the undercoating is obscured and the neurofilaments become interwoven in some parts. In the first internode of the myelinated axons, as the swellings become larger, the neurofilaments lose their parallel orientation and become intermingled. Large accumulation of neurofilaments resembling spheroids in the perikarya of large anterior horn cells suggests that spheroids could be derived not only from the axon including the proximal portion, but also from the perikarya. Structures apparently identical to axonal spheroids are observed at the light and electron microscopic levels in the proximal portion of axons of anterior horn cells in animal models intoxicated with β, β'-iminodipropionitrile (IDPN), or with aluminum, in hereditary canine spinal muscular atrophy (HCSMA). The pathogenetic mechanism is probably associated with an impairment in slow axonal transport which particularly affects the neurofilaments in IDPN and aluminum intoxication. Impairment of slow axonal transport of neurofilaments also plays an important role in the pathogenesis of ALS. The average diameter of even normalappearing initial segment is larger in ALS than in the controls. The perikarya connected with the swollen proximal axons and their dendrites almost always appear normal. These findings suggest that the slow axonal transport of neurofilaments is probably impaired in this portion of the axon at an early stage in ALS as well as animal models for human ALS. However, techniques to analyze slow axonal transport in humans still remain tobe developed. Recently, overexpression of neurofilament subunits in transgenic mice produces a condition resembling ALS. The transgenic model may offer an interesting perspective not only for testing therapeutic strategies but also for investigating in a systematic way the various genetic and environment factors controlling the onset and progression of the disease and might yield new insights on the etiology of ALS. 相似文献
33.
从1985年起,应用胫骨骨条植骨结合多根克氏针内固定治疗股骨颈骨折21例,经随访7个月—48个月,优17例、良3例、差1例。通过临床观察,用自体胫骨骨条植骨提供活的骨细胞及诱导成骨,能促进加速骨折愈合。本手术方法简单、安全 相似文献
34.
Summary A new modification of microvenous anastomosis, which has increased patency rates while simultaneously decreasing the difficulty of the procedure, is presented in this paper. The primary purpose of this study was to compare the classical and the temporary stent techniques of microvenous anastomosis. Because of problems such as mixing and tangling of strings during insertion and tying of the last four sutures while applying the temporary stent technique, we decided to modify the procedure. The silastic tube was removed through an incision (venotomy), distant from the actual suture line. This modified technique and the other above mentioned techniques were carried out on rat femoral veins. The results indicate that this modification has increased patency rates, shortened the time of anastomosis and facilitated the procedure. 相似文献
35.
O. GAROFALO P. G. E. KENNEDY M. SWASH† J. E. MARTIN† P. LUTHERT B. H. ANDERTON P. N. LEIGH 《Neuropathology and applied neurobiology》1991,17(1):39-45
The expression of two heat shock proteins, HSP72 and p57, in addition to ubiquitin, has been studied immunocytochemically in nine amyotrophic lateral sclerosis (ALS) cases and 10 age-matched controls. HSP72 and p57 antibodies did not identify the characteristic ubiquitin-immunoreactive inclusions present in anterior horn cells in ALS spinal cord. Antibodies to HSP72, but not to p57 or ubiquitin, strongly labelled structures corresponding to polyglucosan bodies in spinal grey matter. Such immunoreactive profiles were more abundant in ALS cases, although they were also present in control material. They were sometimes identified by haematoxylin and eosin and periodic acid Schiff reaction, but were not labeled by phosphotungstic acid haematoxylin or by antibodies to glial fibrillary acidic protein. Although ubiquitin, HSP72 and p57 are stress-induced proteins, they are expressed differently and might therefore have different significance in neuronal degeneration. 相似文献
36.
Summary This study evaluates healing fractures of the femoral neck in dogs by using standard radiography, intraosseous venography, India ink staining and histology.The 45 animals were divided into three groups, one of which was not treated, but in the other two the fracture was fixed with a screw or two Kirschner wires.Our results suggest that, when intraosseous venography was positive, India ink injection was also positive, and the late phase of fracture healing was reached.
Résumé Etude de la consolidation des fractures du col fémoral chez le chien à l'aide des radiographies standard, de la phlébographie osseuse, de la coloration par l'encre de Chine et de l'examen anatomopathologique. Les animaux ont été divisés en trois groupes, dans l'un la fracture n'a pas été traitée, dans les deux autres elle a été fixée soit par une vis, soit par deux broches de Kirschner. Les résultats tendent à montrer que lorsque la phlébographie est positive, la coloration par l'encre de Chine l'est également et que la phase ultime de la consolidation est atteinte.相似文献
37.
38.
39.
目的:探求上唇外侧组织瓣在修复较大面积下唇缺损中的作用。方法:根据患者下唇缺损情况,设计上唇外侧组织瓣,旋转后插入缺损组织,同时在缺损吻合处,将上层外侧旋转瓣内侧粘膜肌肉向外牵拉形成部分新的红唇,然后逐层相对缝合,修复缺损。结果:自2003年1月应用此方法修复患者6例,术后随访1~2年,唇部外形好,无流涎,无口闭合不全,效果满意。 相似文献
40.
目的:探讨超声引导下压迫法修复冠脉介入术后假性动脉瘤的可行性和方法。方法:4例冠脉介入术后腹股沟搏动性肿块患者,经彩色多普勒超声确诊股动脉假性动脉瘤,采用实时超声定位及监测下直接压迫法修复股动脉破裂口。结果:3例股动脉假性动脉瘤在超声引导下压迫修复成功,1例失败,未出现并发症。结论:早期超声引导下压迫法结合绷带加压包扎是治疗冠脉介入术后假性动脉瘤的有效方法,简便安全,值得推广。 相似文献