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1.
377例双向分化恶性肿瘤血管生成拟态临床意义分析   总被引:1,自引:0,他引:1  
目的:探讨双向分化恶性肿瘤组织中血管生成拟态的临床意义.方法:收集1955~2000年间我院病理科石蜡包埋双向分化恶性肿瘤样本887例,其中临床和病理资料完整的377例作为研究对象,分为有血管生成拟态组和无血管生成拟态组,分析具有血管生成拟态肿瘤的临床意义.结果:除滑膜肉瘤外(P=0.759),恶性黑色素瘤(P=0.038 2)、间皮肉瘤(P=0.035 6)、横纹肌肉瘤(P=0.028 2)中具有血管生成拟态的肿瘤患者生存时间明显低于无血管生成拟态肿瘤患者,两者比较差异有显著性.结论:具有血管生成拟态的双向分化恶性肿瘤恶性度高、血道转移早、临床预后差.  相似文献   
2.
Adjuvant arthritis (AA) is a T cell mediated disease which can be induced in genetically susceptible rats by immunization with heat-killed Mycobacterium tuberculosis ( Mt ) suspended in incomplete Freund's adjuvant. The critical mycobacterial T cell epitope for the induction of AA was previously identified as residues 178-186 of the mycobacterial 65 kDa heat shock protein ( Mt. hsp65 178-186 ). It was suggested that the development of AA was due to molecular mimicry between a mycobacterial epitope and a cartilage-associated self-antigen. However, until now such cartilage-associated mimicry epitope has not been identified. In this study we designed a computer search profile to predict mimicry self-epitopes, and investigated whether one or more of these self-epitopes could serve as mimicry epitopes in AA. Although several of these self-epitopes were recognized by arthritogenic T cells, no cross-reactivity was found between T cells specific for these self-epitopes and Mt. hsp65 178-186 specific T cells.  相似文献   
3.
《Social neuroscience》2013,8(4):393-400
Tendency to mimic others' emotional facial expressions predicts empathy and may represent a physiological marker of psychopathy. Anatomical connectivity between amygdala, cingulate motor cortex (M3, M4), and facial nucleus demonstrates a potential neuroanatomical substrate for mimicry, though pharmacological influences are largely unknown. Norepinephrine modulation selectively impairs negative emotion recognition, reflecting a potential role in processing empathy-eliciting facial expressions. We examined effects of single doses of propranolol (beta-adrenoceptor blocker) and reboxetine (selective norepinephrine reuptake inhibitor) on automatic facial mimicry of sadness, anger, and happiness, and the relationship between mimicry and empathy. Forty-five healthy volunteers were randomized to 40 mg propranolol or 4 mg reboxetine. Two hours after drug subjects viewed and rated facial expressions of sadness, anger, and happiness, while corrugator, zygomatic, and mentalis EMG were recorded. Trait emotional empathy was measured using the Balanced Emotional Empathy Scale. EMG confirmed emotion-specific mimicry and the relationship between corrugator mimicry and empathy. Norepinephrine modulation did not alter mimicry to any expression or influence the relationship between mimicry and empathy. Corrugator but not zygomaticus mimicry predicts trait empathy, consistent with greater anatomical connectivity between amygdala and M3 coding upper facial muscle representations. Although influencing emotion perception, norepinephrine does not influence emotional facial mimicry or its relationship with trait empathy.  相似文献   
4.
Vasculogenic mimicry (VM) has been found in prostate cancer (PCa) as an independent marker of poor prognosis. To investigate the correlation between VM and bone metastasis in PCa, a total of 80 cases were analyzed by CD31 and PAS dual-staining as well as the follow-up data. All cases were divided into two groups: VM-positive and VM-negative (VM-pos/VM-neg). Immunohistochemical staining for investigating the expression of Casepase-3, Bcl-2/Bax, and SA-β-gal was performed. 28 of the 80 PCa cases exhibited VM structure (35.0%). The incidence of bone metastasis in the VM-pos and VM-neg was 67.9% (19/28) and 38.5% (20/52), respectively. The positive rate of Casepase-3 and Bcl-2 expression was significantly different of the two groups (Caspases-3: VM-pos 71.4%, 20/28 vs VM-neg 42.3%, 22/52; Bcl-2: VM-pos 35.7%, 10/28 vs VM-neg 65.4%, 34/52). Bcl-2/Bax ratio of the VM-pos (0.71 ± 0.22) was lower than that of the VM-pos (0.89 ± 0.13). In addition, a higher frequency of SA-β-gal was detected in VM-pos (64.29 ± 86.42) than in VM-neg (25.37 ± 72.21). Taken together, our findings demonstrate that PCa with VM has the tendency to develop bone metastasis. Activations of cell apoptosis and senescence regulation pathways may play important roles in the formation process of VM structure.  相似文献   
5.
魏子龙  黄强  储亮  刁艺  董军  王爱东  兰青 《肿瘤》2007,27(6):437-440
目的:探讨干细胞标志物ABCG2与肿瘤血管生成相关蛋白VEGF、CD34、VLA-2α在荷人脑胶质瘤裸小鼠移植瘤中的表达,同时运用CD34-PAS双染法观察移植瘤中的血供模式。方法:建立人脑胶质瘤裸小鼠皮下移植瘤模型30例。所有标本同时行HE染色和免疫组化检测,以正常人脑组织6例作为对照。光镜下检测上述基因的表达率和表达部位,并观察移植瘤中的血管生成模式。结果:ABCG2、VEGF、VLA-2α在移植瘤组织中阳性表达率均为100%,平均阳性细胞占有率分别为(3.93±1.438)%、(34.84±6.212)%、(30.33±4.428)%;CD34标记的微血管密度(MVD)计数平均达29.78±5.88个;内皮细胞被覆的血管、马赛克血管及拟态血管三种血供模式在移植瘤组织中均存在。结论:ABCG2高表达的细胞有亲血管分布趋向,VEGF、VLA-2α在移植瘤血管生成中起重要作用;恶性程度较高的移植瘤组织中存在着三种不同的血供模式。  相似文献   
6.
双向分化肿瘤血管生成拟态的组织微阵列研究   总被引:28,自引:1,他引:27  
Hao X  Sun B  Zhang S  Zhao X 《中华医学杂志》2002,82(19):1298-1302
目的 探讨在双向分化肿瘤中是否存在肿瘤细胞通过自身变形并模拟产生血管样通道而达到自身血液供应的方式 ,即血管生成拟态 (VM )。方法 采用免疫组化和PAS双重染色技术研究双向分化肿瘤内血管的生成模式 ,收集双向分化肿瘤恶性黑色素瘤 (高度恶性 30例、低度恶性 30例 ) ,滑膜肉瘤 (高度恶性 2 3例、低度恶性 13例 ) ,间皮肉瘤 (2 6例 ) ,上皮样肉瘤 (4例 )及具有双向分化倾向的腺泡型横纹肌肉瘤 (高度恶性 16例、低度恶性 16例 )共 15 8例 ,制作成组织芯片 ,进行CD31和PAS双重染色 ,通过网格计数法比较这些肿瘤中CD31和PAS阳性图案围成的管道面积 ,以其差异研究血管生成拟态。并且比较高度恶性肿瘤和低度恶性肿瘤血管生成拟态的差异。结果 双向分化肿瘤中CD31和PAS阳性图案围成的管道面积差异具有统计学意义 (P <0 .0 1)。同时观察到细胞异型性小的双向分化肿瘤形成血管生成拟态的例数明显少于瘤细胞异型性大的双向分化肿瘤形成血管生成拟态例数 ,其差异具有统计学意义 (P <0 .0 5 )。在明显具有血管生成拟态的点阵中见PAS阳性的血管样图案内无内皮细胞衬覆但有红细胞存在 ,并可见双向分化肿瘤的瘤细胞可表达CD31抗原和PAS阳性物质。结论 双向分化肿瘤内的肿瘤细胞可通过自身变形并且与细胞外基质  相似文献   
7.
目的 探讨三维彩色能量血管造影成像在中老年阳痿患者诊断中的实用价值。方法 应用三维彩色能量血管造影成像于注射前列腺素E1前及注药后5min,对398例中老年阳痿患者及15例正常对照者的阴茎动脉进行检查。结果 注射药物后5min对照组阴茎动脉走行较直,空间结构清楚;阳痿患者的阴茎动脉走行纡曲,增宽,呈串珠状,且空间结构紊乱。结论 三维彩色能量血管造影成像能较清楚地显示阴茎动脉的走行情况,立体反映阴茎动脉分布特点,对阳痿的诊断及鉴别诊断有益。  相似文献   
8.
肿瘤血管生成拟态研究新进展   总被引:1,自引:1,他引:0  
血管生成拟态是指具有可塑性、侵袭性的肿瘤细胞所形成的非内皮细胞衬覆的微血管通道,其在体内显示为过碘酸席夫染色阳性和CD31染色阴性的图案,在体外三维培养体系中显示为管状或图案样的网络,其可能与肿瘤的侵袭转移潜能以及较差的临床预后有关。  相似文献   
9.
王丹 《医学综述》2010,16(14):2143-2145
近几年,人们先后在黑素瘤、肝细胞癌等恶性肿瘤中发现了血管生成拟态。血管生成拟态是肿瘤细胞自身形成的,参与肿瘤的微循环。血管生成拟态的调节与基因、血管上皮钙黏素、Twist1细胞核的表达等相关。血管生成拟态是预后不良的标志,预测低分化、高浸润、高转移和低生存率。因而抗肿瘤治疗时,经典抗血管治疗联合抗血管生成拟态治疗成为必要。  相似文献   
10.
Objective: To investigate the vasculogenic mimicry formation induced by hypoxia in Ⅱ-Ⅲ human glioma cell and the effect of alphastatin peptide suppressing the hypoxia-induced vasculogenic mimicry formation and the mechanism. Methods: MTT, Transwell and three- dimentional culture were used to detect the proliferation, migration and tubule formation of SHG44. The expression of vascular endothelial growth factor-α(VEGF-α, erythropoietin-producing hepatocellular carcinoma-A2 (EphA2) and matrix metalloproteinases 2 (MMP2) was detected by RT-PCR and Western blotting analysis. Results: The OD490 in hypoxia group was 0.60±0.06 and in control group was 0.46±0.05. The number of cell migration was 178.71±18.81 in hypoxia group and 85.86±17.92 in control group. The tubule formation was 56.80±12.21 in hypoxia group and 4.20±2.62 in control group. The proliferation, migration and tubule formation in hypoxia group were significantly higher than that in control group. The expression of VEGF-α, EphA2 and MMP2 was upregulated in hypoxia. When various concentrations of alphastatin (100, 1 000, 10 000 nmol/L) were added to hypoxia group, the numbers of cell migration were 142.57±12.12, 92.71±17.68, 30.00±7.72 and the tubule formation were 47.71±10.58, 18.86±8.40, 8.43±5.62. The cell migration and tubule formation were significantly suppressed by alphastatin in a dose-dependent manner. In alphastatin group, the phosphorylation of EphA2 protein (P=0.037, F=4,629) and activation of MMP2 protein (P=0.005, F=9.331) were significantly suppressed but there was no change in VEGF-α protein. Conclusion: Ⅱ-Ⅲ human glioma cell is able to form vasculogenic mimicry induced by hypoxia and alphastatin peptide can suppress the hypoxia-induced vasculogenic mimicry. VEGF-α induced EphA2 phospharilation and MMP2 activation maybe the key pathway to form vasculogenic mimicry.  相似文献   
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