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101.
Fukunaga M 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2000,108(4):287-292
A case of a rare vascular tumor, intravenous tufted angioma, is described. A 51-year-old Japanese man presented with a 12x8 mm solitary reddish nodule on the right foot, which had been found at birth. Histologically, the tumor was confined to a malformed vein and was characterized by nodular aggregates of plump cells. The aggregates showed a compact proliferation of round cells, including capillary-forming cells. Venous angiomatous areas were also observed. No multinucleated giant cells were seen. Immunohistochemically, the capillary-forming cells in the aggregates and the endothelial cells in the angiomatous areas were positive for endothelial markers (factor VIII-related antigen, CD31, CD34). Pericyte-like cells expressing alpha-smooth muscle actin and muscle actin, and macrophage-like cells, which stained for factor XIIIa, were intermingled in the cellular aggregates. Flow cytometric analysis showed diploidy. The tumor may be a hamartomatous lesion modified by secondary reactive changes, and it may represent a distinctive clinicopathological entity that is closely related histogenetically and perhaps pathologically to tufted angioma and the recently described "giant cell angioblastoma". 相似文献
102.
银杏叶提取物对血管性痴呆大鼠海马突触素表达的影响 总被引:4,自引:2,他引:4
目的:研究银杏叶提取物(EGb761)对血管性痴呆模型大鼠海马突触素表达的影响。方法:以双侧颈总动脉反复夹闭再通同时腹腔注射硝普钠建立血管性痴呆模型大鼠,采用Morris 水迷宫和免疫组化方法分别观察大鼠空间学习记忆能力及海马突触素(SYN)表达情况。结果:模型组大鼠在1月、2月和4月不同时点测得的Morris水迷宫逃避潜伏期(EL)均较假手术组明显延长(P<0.01),药物组EL均显著短于模型组,但仍长于假手术组(P<0.05或P<0.01);模型组海马SYN表达弱于假手术组,而药物组海马SYN表达高于模型组(P<0.01)。结论:EGb761增加海马结构SYN表达可能是其改善VD大鼠学习记忆障碍的重要机制。 相似文献
103.
Honecker F Kersemaekers AM Molier M Van Weeren PC Stoop H De Krijger RR Wolffenbuttel KP Oosterhuis W Bokemeyer C Looijenga LH 《The Journal of pathology》2004,204(2):167-174
Intercellular contacts, mediated by E-cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E-cadherin correlates with tumour progression and invasive behaviour. beta-catenin is involved in a number of different processes, including cell--cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal-transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E-cadherin and beta-catenin by immunohistochemistry. E-cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ/intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non-seminoma cells. beta-catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post-pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non-seminoma cells were frequently found to express beta-catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E-cadherin or beta-catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E-cadherin expression did not correlate with vascular invasion. E-cadherin and beta-catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs. 相似文献
104.
Ken Dewitte Marc Claeys Emeline Van Craenenbroeck Koen Monsieurs Hein Heidbuchel Vicky Hoymans Tibor Stoop 《Pathophysiology》2019,26(1):53-59
Aims
We explored the effect of remote ischaemic conditioning (RIC) on endothelial function and on circulating mediators.Methods and results
In 20 healthy male volunteers (mean age 31?±?10 years), flow-mediated dilation (FMD) was measured before and after 20?min of arm ischaemia, followed by reperfusion. Remote ischaemic conditioning (RIC) was performed by applying 3 cycles of 5?min of ischaemia of the leg at the onset of index arm ischaemia. Each volunteer underwent the IR-induced vascular injury protocol with and without RIC in a crossover study design.In the control group, IR significantly reduced FMD (5.9?±?2.9% before IR vs. 2.2?±?3.7% after IR; p?<?0.001). This effect was significantly attenuated by performing RIC (FMD of 5.5?±?3.1% before IR vs. 4.0?±?3.4% % after IR; p for interaction?=?0.01). Serum levels of SOD and ADMA increased significantly whereas MCP-1 and VEGF levels decreased significantly.Only changes in SOD levels were significantly related to the degree of RIC induced protection (r²?=?0.34; p?=?0.018).Conclusion
RIC has protective effects against endothelial IR injury. Our biomarker study suggests that anti-oxidative stress mediators, such as SOD, seem to be more involved in the pathogenesis of RIC-induced protection in humans than angiogenesis factors or chemo-attractant cytokines. 相似文献105.
一氧化氮诱导大鼠肺动脉平滑肌细胞凋亡机制研究 总被引:3,自引:3,他引:3
目的:研究一氧化氮(NO)诱导大鼠肺动脉平滑肌细胞(PASMC)凋亡的作用机制。方法:体外培养Wistar大鼠PASMC,加入NO供体硝普钠(SNP)于常氧和低氧条件下孵育12h或24h,通过流式细胞术碘化丙啶染色法观察PASMC细胞周期时段及凋亡亚二倍体峰变化,应用细胞免疫化学法检测PASMCcaspase-3和NF-κB的表达,同时行DNA断裂琼脂糖凝胶电泳。结果:SNP作用后PASMC出现剂量-依赖性促凋亡作用(P<0.01),表现为凋亡指数与caspase-3表达的不同程度的增强。随凋亡的进展,出现PASMC凋亡核小体DNAladder,同时PASMCNF-κB阳性核表达较对照组少(P<0.01)。结论:外源性NO诱导大鼠PASMC凋亡,caspase-3与NF-κB可能涉及PASMC凋亡的调控信号途径。 相似文献
106.
超短波治疗慢性肺源性心脏病患者的初步探讨 总被引:1,自引:0,他引:1
目的:探讨超短波对慢性肺心病CCP患者的临床应用价值。方法:急性发作期CCP患者87例分为超短波治疗组45例和对照组42例,治疗组在常规治疗的基础上给予超短波治疗,对照组行常规治疗。治疗前后分别测定两组患者血浆中血管内皮生长因子VEGF、内皮素(ET-1)含量,动脉血氧分压(PaO2)和平均肺动脉压(mPAP)水平。结果:与对照组比较治疗组治疗后PaO2显著升高(P<0.01),VEGF、ET-1、mPAP明显降低(P<0.01)。VEGF、ET-1与PaO2呈负相关(P<0.01)、与mPAP呈正相关(P<0.01)。结论:超短波可以通过降低肺动脉高压对CCP患者起治疗作用。 相似文献
107.
108.
109.
Yuji Narita Hideaki Kagami Hiroshi Matsunuma Yosuke Murase Minoru Ueda Yuichi Ueda 《Journal of artificial organs》2008,11(2):91-99
Previous attempts to create small-caliber vascular prostheses have been limited. The aim of this study was to generate tissue-engineered small-diameter vascular grafts using decellularized ureters (DUs). Canine ureters were decellularized using one of four different chemical agents [Triton-X 100 (Tx), deoxycholate (DCA), trypsin, or sodium dodecyl sulfate (SDS)] and the histology, residual DNA contents, and immunogenicity of the resulting DUs were compared. The mechanical properties of the DUs were evaluated in terms of water permeability, burst strength, tensile strength, and compliance. Cultured canine endothelial cells (ECs) and myofibroblasts were seeded onto DUs and evaluated histologically. Canine carotid arteries were replaced with the EC-seeded DUs (n = 4). As controls, nonseeded DUs (n = 5) and PTFE prostheses (n = 4) were also used to replace carotid arteries. The degree of decellularization and the maintenance of the matrix were best in the Tx-treated DUs. Tx-treated and DCA-treated DUs had lower remnant DNA contents and immunogenicity than the others. The burst strength of the DUs was more than 500 mmHg and the maximum tensile strength of the DUs was not different to that of native ureters. DU compliance was similar to that of native carotid artery. The cell seeding test resulted in monolayered ECs and multilayered alpha-smooth muscle actin-positive cells on the DUs. The animal implantation model showed that the EC-seeded DUs were patent for at least 6 months after the operation, whereas the nonseeded DUs and PTFE grafts become occluded within a week. These results suggest that tissue-engineered DUs may be a potential alternative conduit for bypass surgery. 相似文献
110.
具有三层管壁结构组织工程血管支架的生物力学性能 总被引:2,自引:0,他引:2
目的针对组织工程血管的体内培养技术路线,对所制备的具有三层管壁结构的组织工程血管支架的生物力学性能进行测试,并研究了壁厚对支架力学性能的影响,以保证后续的动物体内移植实验能顺利进行。方法采用涂敷,喷涂.滤沥的方法制备了具有三层管壁结构(多孔PLGA层.致密PU层.多孔PLGA层)的可降解组织工程血管支架,用自制的设备测试了其爆破强度和径向顺应性,并对血管支架进行了缝合强度的测试。结果所制备的厚度为0.295mm-0.432mm的三层结构血管支架的径向顺应性为3.80%/100mmHg-0.57%/100mmHg,爆破强度为160kPa~183kPa,缝合强度为0.63N/针~1.52N/针。结论支架的管壁厚度,尤其是中间层厚度,对支架的力学性能有重要影响。增大壁厚可导致径向顺应性急剧下降,爆破强度和缝合强度线性提高。在所制备的样品中,管壁厚度为0.295mm的支架其综合力学性能最优,可满足血管组织工程体内植入的力学性能要求。 相似文献