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1.
Microglia, as the resident immune cells in the central nervous system, play important roles in regulating neuronal processes, such as neural excitability, synaptic activity, and apoptotic cell clearance. Growth factors can activate multiple signaling pathways in central nervous system microglia and can regulate their immune effects, but whether growth factors can affect the morphological characteristics and ultrastructure of microglia has not been reported. After microinjecting 300 nL of a growth factor cocktail, including 10 μg/mL epidermal growth factor, 10 μg/mL basic fibroblast growth factor, 10 μg/mL hepatocyte growth factor and 10 μg/mL insulin-like growth factor into adult rat cortex, we found that the number of IBA1-positive microglia around the injection area increased significantly, indicating local activation of microglia. All CD68-positive labeling co-localized with IBA1 in microglia. Cell bodies and protrusions of CD68-positive cells were strongly attached to or were engulfing neurons. Characteristic huge phagosomes were observed in activated phagocytes by electron microscopy. The phagosomes generally included non-degraded neuronal protrusions and mitochondria, yet they contained no myelin membrane or remnants, which might indicate selective phagocytosis by the phagocytes. The remnant myelin sheath after phagocytosis still had regenerative ability and formed "myelin-like" structures around phagocytes. These results show that microinjection of a growth factor cocktail into the cerebral cortex of rodents can locally activate microglia and induce selective phagocytosis of neural structures by phagocytes. The study was approved by the Institute of Laboratory Animal Science, Beijing Institute of Basic Medical Sciences(approval No. IACUC-AMMS-2014-501) on June 30, 2014. 相似文献
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妥泰对海人酸致癎大鼠海马神经元线粒体损伤的保护作用 总被引:1,自引:0,他引:1
目的观察海人酸(KA)诱导的癫痫持续状态(SE)、大鼠海马CA3区神经元线粒体超微结构的损伤及妥泰(TPM)的保护作用。方法用TPM干预。用KA诱导大鼠SE2h,并于癫痫终止后3h制作脑切片,用光镜观察神经元的大体损伤,并用电镜进一步观察线粒体的超微结构。结果KA组和TPM组大鼠均出现了线粒体超微结构的损伤,TPM组大鼠的损伤明显减轻。结论KA诱导的SE可导致海马神经元线粒体损伤,妥泰对此具有保护作用。 相似文献
4.
Since the role of cutaneous nerves in the pathogenesis of cutaneous diseases associated with diabetes mellitus is not well defined, cutaneous nerves in ten patients with severe diabetic neuropathy were electron microscopically investigated as a preliminary study. The specimens were taken from normal-appearing skin of their lower extremities. Cutaneous nerves were seen as axon-Schwann cell complexes in which variously degenerated axons and Schwann cells coexisted with normal ones. The degenerative changes were not, however, specific for diabetes mellitus. 相似文献
5.
K. Dorovini-Zis A. P. Zis 《Journal of neural transmission (Vienna, Austria : 1996)》1991,84(1-2):75-84
Summary Autonomic innervation of the adrenal cortex has been demonstrated in several species. Detailed ultrastructural studies on the innervation of the zona fasciculata of the normal human adrenal cortex are lacking. We report herein our observations on the pattern of innervation of the cells of the zona fasciculata of the normal adult human cortex at both the light and electron microscope levels. Postganglionic unmyelinated fibers were observed to descend from a dense capsular meshwork and to be distributed as delicate branches among the columns of endocrine cells. Immunoperoxidase staining confirmed the presence of nerve fibers in the zona fasciculata in a distribution similar to that observed after staining with silver impregnation methods. Ultrastructural findings lent further support to these observations by the demonstration of bundles of unmyelinated fibers with focal enlargements containing terminal boutons with both clear and dense core vesicles in close approximation with the endocrine cells. 相似文献
6.
子宫内膜异位症并发不孕患者子宫内膜超微结构观察 总被引:6,自引:0,他引:6
目的:探讨子宫内膜异位症(EM)并发不孕患者围着床期子宫内膜的超微结构。方法:选择轻度子宫内膜异位症并不孕患者10例为研究组,已生育妇女7例作为对照组,选择在月经周期第19-22天刮取少量子宫内膜,进行扫描及透射电镜观察。结果:异位症患者围着床期子宫内膜出现超微结构改变,内膜表面腺体开口数少,纤毛再生不全,分泌细胞表面微绒毛极少,子宫内膜着床窗的形态学标记-细胞表面胞饮小泡减少 或缺失;胞质肿胀疏松,有的细胞出现核固醇,结论:异位症患者围着床期在位子宫内膜出现超微结构改变,细胞出现轻度变性,可能是其不孕的原因之一。 相似文献
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妇女妊娠期及分娩前后子宫肌层的超微结构研究 总被引:2,自引:0,他引:2
扫描电镜(SEM)和透射电镜(TEM)观察证明,妇女非妊娠期子宫肌层内存在有胶原纤维网(CFN)。妊娠中期和晚期及分后CFN出现以时相性崩解和重建为主要特征的改建过程以适应子宫生理性能的巨大变化和功能需要。平滑肌细胞,成纤维细胞,肌纤维母细胞,巨噬细胞,中性白细胞及肥大细胞参与改建过程。它们既参与CFN的溶解和吸收,又参与其重新形成,显示双重形态和功能。还对CFN改建的机理,参与细胞间的相互作用, 相似文献
9.
A case of a 14 month old Japanese female infant presenting with nasal glioma Is reported. The tumor had been noticed at the nasal radix since birth and had slowly and progressively enlarged. There was no communication between the tumor and the cranial cavity on radiological examination. The tumor was macroscopically anchored to the nasal septum by a fibrous stalk, and histologically consisted of nests or trabeculae of either polygonal or spindle cells with plump eosinophilic cytoplasm and oval nuclei, separated by vascular-rich connective tissue intermingled with multinu-cleated giant cells. These tumor cells were immunohisto-chemically positive for glial fibrillary acidic protein as well as for S-100 protein and vimentin. An electron microscopic examination revealed collagen fibers and basal lamina between the tumor cells and the fibroblasts. Tumor cells possessed abundant intermediate filaments, which showed occasional Rosenthal fiber-like structures, in their cytoplasm and processes. A few oligodendrocytes and cilia of 9 micro-tubule doublets either with or without 2 central microtubules were also noted. These clinicopathological findings suggested that this tumor was once an encephalo(meningo)cele, which probably degenerated as a result of the loss of intracranial communication and then appeared to be isolated from the intracranial tissue. 相似文献
10.
Satoshi Abe 《Journal of orthopaedic science》1997,2(2):75-83
The purpose of this study was to validate the hypothesis of neural histogenesis of Ewing's sarcoma of bone and related tumors
by light microscopic, electron microscopic, and immunohistochemical analysis. We studied 32 round-cell sarcomas (19 cases
of Ewing's sarcoma of bone, 3 extraskeletal Ewing's sarcomas, 5 peripheral primitive neuroectodermal tumors (PNET) and 5 cases
of unclassified small round-cell type of neurogenic sarcoma (NS). Immunoreactivity for MIC2 was observed in all cases of Ewing's
sarcoma and PNET, and in 1 cases of NS. Positive immunoreactivity for neural markers (NSE, synaptophysin, S-100) was found
frequently in some tumors. Ultrastructurally, some specific features of neural differentiation, such as a fragmented basal
lamina and neurosecretory granule-like particles, were found even in typical cases of Ewing's sarcoma of bone, which presented
without a rosette arrangement and were almost negative for neural immuno-markers, but positive for MIC2. These ultrastructural
neural features were observed less frequently in Ewing's sarcoma of bone than in PNET and NS. However, no significant correlation
was demonstrated between the immunoreactivity for neural markers and the ultrastructural and histological neural features.
These results support the hypothesis of a neural origin of Ewing's sarcoma and related neoplasms, and suggest that some overlapping
entity could persist in PNET and Ewing's sarcoma and that this entity could be seen in histological and immunohistochemical
studies of both tumors. 相似文献