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61.
目的 研究异硫氰酸苄酯对人胶质瘤U87MG细胞体外侵袭和凋亡的影响,并初步探讨其作用机制。方法 采用MTS实验考察异硫氰酸苄酯对肿瘤细胞体外增殖的抑制作用;2,5 μmol·L-1异硫氰酸苄酯作用24 h后,采用Transwell实验、黏附实验和划痕实验观察异硫氰酸苄酯对人胶质瘤细胞侵袭、黏附和迁移能力的影响;应用Real-time-PCR和Western blot法检测相应浓度异硫氰酸酯处理后人胶质瘤U87MG细胞中MMP-2、MMP-9、CD44、Survivin、Bcl-2、Net1、RohA、caspase-3、caspase-8和p-AKT的表达变化;应用报告基因技术检测NF-κB转录活性的变化;采用ELISA法测定胞内8-OH-dG含量;10,20 μmol·L-1异硫氰酸酯作用24 h后,采用流式细胞术观察其对细胞凋亡的作用。结果 异硫氰酸苄酯可显著抑制人胶质瘤U87MG细胞体外增殖;与0 μmol·L-1组相比,2,5 μmol·L-1异硫氰酸苄酯对人胶质瘤细胞U87MG侵袭、黏附和迁移能力有明显的抑制作用;不同浓度异硫氰酸苄酯处理后,肿瘤细胞MMP-2、MMP-9、CD44、Survivin、Bcl-2、NET1和RhoA的mRNA和蛋白表达、AKT磷酸化水平和NF-κB转录活性明显下调,caspase-3和caspase-8表达以及8-OH-dG含量显著上调;10,20 μmol·L-1异硫氰酸苄酯可显著诱导细胞凋亡。结论 异硫氰酸苄酯抑制人胶质瘤细胞U87MG的侵袭能力,诱导细胞凋亡,其机制可能与抑制AKT/NF-κB信号转导途径,进而调节侵袭和凋亡相关基因表达有关。 相似文献
62.
目的:探讨解剖Y型钢板的临床应用价值。方法:报告36例解剖Y型钢板内固定肱骨远端粉碎性骨折,进行临床分析讨论,其中列,女8例,平均年龄36.8岁。36例中均行肘后标准切口尽骨鹰嘴截骨暴整个肱骨远端,Y型钢板、螺钉内固定。结果:本组随访1~5年,其中优良率86.2%。结论:解剖Y型钢板治疗治疗肱骨远端粉碎骨折,效果确切,术后有利早期活动关节,减少并发症。 相似文献
63.
64.
目的 研究cyclinD1/p16-pRB路径在脑胶质瘤中的异常情况,并对其意义进行分析。方法 用免疫且化对23例脑胶质瘤(包括14例星形细胞瘤和9例胶质母细胞瘤)及6例正常脑组织中3种因子的表达进行检测,并分析了实验结果与肿瘤分型的关系以及各个因子在此路径中的作用。结果 23例肿瘤中有17例cyclin D1过度表达(73.9%),13p16和8例pRB缺失(56.5%和34.8%),3种因子的 相似文献
65.
C Daumas-Duport V Monsaigneon S Blond C Munari A Musolino J P Chodkiewicz O Missir 《Journal of neuro-oncology》1987,4(4):317-328
Histologic features of 100 supra-tentorial astrocytomas, oligodendrogliomas and oligo-astrocytomas obtained from serial stereotactic biopsies were compared with the corresponding CT scans. Topographic comparisons provided by visualization of the biopsy trajectories on post-biopsy CT scans were available in 24 cases. Areas of contrast enhancement and low attenuation were compared with the histologic grade of malignancy, tumor delimitation and structural type. The latter was determined as follows: Type I-solid tumor tissue without significant peripheral isolated tumor cells; Type II-solid tumor tissue associated with peripheral isolated tumor cells; Type III-isolated tumor cells only.There was a strong correlation between areas of contrast enhancement and tumor microvascularity. In addition, contrast enhancement occurred only in the solid tumor tissue component of the neoplasm. This correlation accounted for the relationship observed between CT images and the structural type of glioma. Contrast enhancement was constant in structural type I gliomas, inconstant in structural type II, and absent in structural type III. No correlation was found between malignancy and contrast enhancement. Contrast enhancement occurred in all grades of malignancy but was a constant feature of grade 4 gliomas. The volume of the tumors could not be reliably determined from CT images alone. Areas of low attenuation on contrast CT scans could correspond to either peritumoral edema or to edematous parenchyma infiltrated by isolated tumor cells.Serial stereotactic biopsies combined with calculations based on the CT scan provided a more precise definition of the tumor volume and identification of structural type. Such classification may prove useful in prospective analysis of various modes of therapy. 相似文献
66.
Parvathy D Kurup Thomas F Pajak James S Nelson JoAnne Mansell Frank R Hendrickson Lionel Cohen Thomas W Griffin 《Journal of neuro-oncology》1986,4(2):123-129
The treatment of supratentorial malignant gliomas has continued to be a major problem for neurosurgeons and oncologists. Post-operative conventional radiotherapy is known to prolong survival and to enhance the quality of life. Local persistence of tumor kills the majority of patients. Fast neutron irradiation is being utilized to treat malignant gliomas based on its reputed radiobiological advantages for treatment of large tumors and the encouraging preliminary reports showing tumor eradication in post-radiation biopsy and autopsy specimens. This paper reviews the results of fast neutron irradiation alone and in combination with photons and hypoxic cell sensitizers. Survival comparisons do not show any superiority for neutrons compared to conventional radiation. However, post-neutron radiation tissue samples have shown less agressive and minimal residual tumor in many instances. At the same time radiation necrosis has emerged as a significant problem. In summary, even though neutron irradiation can eradicate malignant gliomas a therapeutic window has yet to be identified.
Address for offprints: Neutron Therapy Facility, MS-301, P.O. Box 500, Batavia, IL 60510, USA 相似文献
67.
Francine J. Vriesendorp Joseph F. Pasternak Dennis R. Groothuis 《Journal of neuro-oncology》1987,5(4):289-297
Systemic arterial hypertension was induced with epinephrine in 15 rats with 39 transplanted RG-2 brain tumors in an attempt to increase blood-to-tissue transport of a water-soluble compound. In 4 rats, hypertension was induced acutely (< 5 sec), and in 11 hypertension was induced more slowly (over 5 min). Regional values of the unidirectional blood-to-tissue transfer constant (K) of alpha aminoisobutyric acid were measured with quantitative autoradiography. Mean arterial blood pressure (BP) over the experimental period increased from 117 ± 17 mmHg (SD) to 168 ± 18 mmHg in the rats with slowly induced hypertension, and from 124 ± 4 to 142 ± 5 mmHg in the acute hypertension group. Peak BP was 208 ± 16 in the first group and 216 ± 13 mmHg in the second. Intracerebral hemorrhage occurred in 10/15 animals, and there was disruption of BBB in tumor-free brain in 10/15 animals. Averaged mean whole tumor K of AIB in all hypertensive rats was 0.052 ± 0.022 ml/g/min, compared to 0.037 ± 0.015 ml/g/min in normotensive controls; there was no difference in mean tumor K between the two hypertensive groups. However, in intraparenchymal tumors without hemorrhage, K was only 0.039 ± 0.013 ml/g/min. Although the mean K of AIB was higher in brain tumors of the hypertensive rats, the increase is unlikely to be meaningful in terms of augmented delivery of watersoluble drugs to brain tumors, and the high incidence of intracerebral hemorrhage countermands any clinical use of this approach. 相似文献
68.
H. Kroh 《Acta neuropathologica》1987,73(1):92-98
Summary The histology and ultrastructure of ten spinal cord gliomas, mainly oligodendrogliomas, induced transplacentally in rat with ethylnitrosourea were studied. The characteristic feature of seven spinal tumours was distinct delineation of neoplastic tissue from the edematous surrounding zone by a ring of irregular, proliferating capillaries, among which immature capillary buds prevailed. The alterations were proliferation of endothelium with endothelial overlapping, elongation of interendothelial junctions and enhancement of pinocytotic vesicles on luminal and abluminal surfaces. The basal membranes, besides other changes, were often replaced by some floccular condensations. In the edematous zone the capillary walls were deprived of contact with glial processes. The lack of contact between astrocytic processes and vascular wall may contribute to the persistent immature state of peripheral capillaries. 相似文献
69.
Immunocytochemistry has been applied extensively to the diagnosis of intracranial tumours, but meningiomas still present a diagnostic problem. However, desmosomes have been shown by electron microscopy to be present in meningiomas, and this distinguishes them from gliomas. This paper describes a new monoclonal antibody, 11-5F, against desmosomal proteins 1 and 2 (desmoplakins) and assesses its usefulness in the diagnosis of meningiomas and other intracranial tumours. A total of 74 surgically removed intracranial tumours were examined by fluorescent antibody staining with 11-5F on frozen sections. In addition, a panel of antibodies against cytokeratin, vimentin, glial fibrillary acidic protein, and S100 protein was used. 11-5F stained 30/30 meningiomas and 14/14 metastatic carcinomas but 0/30 gliomas, thus distinguishing meningiomas and metastatic carcinomas from gliomas. The distinction between meningiomas and metastatic carcinomas on the basis of intermediate filaments staining was more difficult because neither the anticytokeratin nor the antivimentin antibody was specific for either tumour type. This study emphasizes the value of antidesmosomal antibodies as an important adjunct to the diagnosis of intracranial tumours. 相似文献
70.
Intracranial ependymomas: Prognostic aspects 总被引:2,自引:0,他引:2
According to the grading of brain tumors as proposed by the WHO in 1976, out of 128 ependymomas 83 tumors could be classified as grade II and 38 as grade III Only seven subependymomas were benign and could be assigned to grade I.In contrast to most series known from the literature, 73 ependymomas were located above the tentorium and only 55 in the posterior cranial fossa. The grade of malignancy rised with an increased distance from the ventricular level.Macroscopically complete exstirpations were usually possible in hemispheric ependymomas, whereas tumors arising from the floor of the fourth ventricle often allowed only a partial removal. The operative mortality in the infratentorial group was more than twice as that in the supratentorial group.Postoperative survival was predominantly dependent on the histologic grade of malignancy. The five year survival rate without recurrence was 57.4% in grade II ependymomas as compared to 24.1% in grade III ependymomas. It could be improved by postoperative radiation therapy in both groups of malignancy. The almost identical longterm results indicate that even in less malignant ependymomas new tumor growth will occur later on. 相似文献