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1.
Objective: To investigate the relationship between the expression of endothelial nitric oxide synthase (eNOS), vascular endothelial growth factor (VEGF) and angiogenesis in primary astrocytoma. Methods: Thirty-seven primary astrocytomas and 4 astrocytic hyperplasia samples were collected and divided into three groups according to histological grade. The expression of eNOS, VEGF and factorⅧrelated antigen (FⅧRAg) were assayed by immunohistochemistry. Microvascular density was assessed by FⅧRAg immunoreactivity. The intensity of immunoreactivity was graded according to the percentage of positive tumor cells. Results: No eNOS and VEGF were expressed in the astrocytes and vascular endothelium in astrocytic hyperplasia. The expression of eNOS or VEGF was light in low-grade astrocytoma and strong in glioblastoma. eNOS expression in astrocytoma was very positively correlated with VEGF. eNOS and VEGF expression in anaplastic astrocytoma was median in contrast to the low grade astrocytoma and glioblastoma. Lower microvascular density was found in low grade astrocytoma than that in higher grade malignant ones. The expressions of eNOS and VEGF were correlated with microvascular density and tumor malignancy. Conclusion: This finding suggests that eNOS and VEGF may have cooperative effect in tumor angiogenesis and play an important role in the pathogenesis of primary astrocytoma.  相似文献   

2.
Objective： To investigate whether vascular endothelial growth factor （VEGF） gene plasmid carried by polytetrafluoroethylene （PTFE） vascular graft materials could transfect endothelial cells （ECs） and promote their growth. Methods： PTFE vascular graft materials carried with pCDI-hVEGF121, pCDI or pEGFP were incubated in Tris-buffer solution and the values of optical density of 260 nm at different time were plotted, then the DNA controlled release curve was made. ECs derived from human umbilical vein were seeded on the pCDI-hVEGF121/pCDI/pEGFP-PTFE materials or tissue culture plates, ECs numbers were counted and VEGF protein concentrations at different time were measured by enzyme-linked immunoadsorbent assay method. Green fluorescent protein （GFP） expression in ECs on pEGFP-PTFE materials was examined with fluorescence mi- croscopy. Results： The controlled release curve showed that the gene released from PTFE materials was rapid within 8 h, then slowed down and that the gene released continuously even after 72 h. At 24, 72 and 120 h, ECs number and proliferation rate of pCDI-hVEGFI21-PTFE materials were higher than those ofpCDI or pEGFP-PTFE materials （P〈0.05）. VEGF protein concentration of pCDI-hVEGF121-PTFE materials was higher than that of pC DI or pEGFP-PTFE materials at 6, 24, 72 and 120 h （P〈0.01）. GFP expression in ECs on the pEGFP-PTFE materials could be detected by fluorescence microscopy. Conclusion： PTFE graft can be used as a carrier of VEGF gene plasmid, VEGF gene carried by PTFE can transfect ECs and promote ECs growth.  相似文献   

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Ds-echinoside A (DSEA), a non-sulfated triterpene glycoside, was isolated from the sea cucumber Pearsonothuria graeffei. In vitro and in vivo investigations were conducted on the effects of DSEA on tumor cell adhesion, migration, invasion, and angiogenesis. In this study, we found that DSEA inhibited the proliferation of human hepatocellular liver carcinoma cells Hep G2, with a half-maximal inhibitory concentration (IC50) of 2.65 μmol/L, and suppressed Hep G2 cell adhesion, migration, and invasion in a dose-dependent manner. DSEA also reduced tube formation of human endothelial cells ECV-304 on matrigel in vitro and attenuated neovascularization in the chick embryo chorioallantoic membrane (CAM) assay in vivo. Immunocytochemical analysis revealed that DSEA significantly decreased the expression of matrix metalloproteinase-9 (MMP-9), which plays an important role in the degradation of basement membrane in tumor metastasis and angiogenesis. DSEA also increased the protein expression level of tissue inhibitor of metalloproteinase-1 (TIMP-1), an important regulator of MMP-9 activation. From the results of Western blotting, the expressions of nuclear factor-kappa B (NF-κB) and vascular endothelial growth factor (VEGF) were found to be remarkably reduced by DSEA. These findings suggest that DSEA exhibits a significant antimetastatic activity through the specific inhibition of NF-κB-dependent MMP-9 and VEGF expressions.  相似文献   

5.
Homoharringtonine (HHT) has currently been used successfully in the treatment of acute and chronic myeloid leukemias and has been shown to induce apoptosis of different types of leukemic cells in vitro. Emerging evidence suggests that angiogenesis may play an important role in hematological malignancies, such as leukemia. How ever, whether HHT can relieve leukemia by anti-angiogenesis is still unknown. We investigated the anti-angiogenesis potential of HHT with the human umbilical vein endothelial cell line (ECV304) and leukemic cell line (K562) in vitro. Cellular proliferation was determined by MTT assay and apoptosis was analyzed by flow cytometry. The mRNA expression of vascular endothelial growth factor (VEGF) was assessed by RT-PCR and VEGF protein production was detected by Western blot. Inhibition of cell proliferation and induction of apoptosis by HHT were discovered in ECV304 cells, and appeared in a dose- and time-dependent manner. Also, treatment with HHT caused down-regulation of VEGF mRNA expression in K562 cells in similar dose- and time-dependent manner and inhibition of VEGF protein production in K562 cells in response to the enhancing concentration of HHT. The results demonstrated that HHT could also induce apoptosis in endothelium and down-regulate VEGF expression in K562 cells. In conclusion, we believe HHT has anti-angiogenesis potential and speculate that HHT might exert its anti-leukemia effects via reduction of angiogenesis.  相似文献   

6.
INTRODUCTION Homoharringtonine (HHT) is a cephalotoxin alkaloid with anti-leukemic activity and had been used successfully in the treatment of acute and chronic myeloid leukemias (O払rien et al., 1995; 1999; Feldman et al., 1992). The principal mecha-nism of action by HHT is the inhibition of protein synthesis in a dose- and time-dependent manner by binding to ribosome and inhibiting polypeptide chain elongation (Tujebajeva et al., 1989; Zhou et al., 1995). HHT had been shown to indu…  相似文献   

7.
以4.5 G PAMAM（4.5代聚酰胺-胺型）树状大分子为保护剂,利用微波法还原HAuCl4溶液制备金纳米粒子。考察了在同一照射条件下,4.5 G PAMAM与HAuCl4不同物质的量比对金纳米粒子大小及形状的影响。利用紫外可见分光光度计、透射电子显微镜以及X射线衍射分析对其进行了表征。结果表明,照射时间相同时,以30 s为例,当4.5 G PAMAM与HAuCl4物质的量比为5时,得到的金纳米粒子最小;随着4.5 G PAMAM与HAuCl4物质的量比值的减小,金纳米粒子变大,且发生了不同程度的聚集。  相似文献   

8.
Angiogenesis is required for solid tumor growth and facilitates tumor progression and metastasis. The inhibition effects of O-（chloroacetyl-carbamoyl） fumagillol （TNP-470）, an angiogenesis inhibitor, and gemcitabine, a chemotherapeutic agent, on expression of growth factors were investigated using human pulmonary adenocarcinoma cell line, A549. The A549 cells were divided into four groups： control group, 10^-6 mg/ml gemcitabine treated group, 10^-4 mg/ml TNP-470 treated group and gemcitabine＋TNP-470 treated group. The mRNA and protein expression of vascular endothelial growth factor （VEGF） and its receptors, FMS-like tyrosine kinase-l （FLT-1） and kinase insert domain-containing receptor （KDR）, in different groups were measured. The growth of A549 cell cultured with gemcitabine or TNP-470 was inhibited in an almost dose-dependent manner. Although gemcitabine （10^-6 mg/ml） alone and TNP-470 （10^-4 mg/ml） alone had no effect on the mRNA and protein expression of VEGF and its receptors （FLT-1, KDR） in A549 cells compared to the control （P〉0.05）, 10^-6 mg/ml gemcitabine in combination with 10^-4 mg/ml TNP-470 had significant effect （P〈0.01）. Moreover, combination of the two drugs significantly inhibited the mRNA expression of VEGF, FLT-1 and KDR compared to either drug alone （P〈0.05）. This study suggests that combined treatment with TNP-470 plus gemcitabine may augment the antiangiogenic and antineoplastic effects in lung cancer cells in vitro.  相似文献   

9.
目的：探讨血管内皮生长因子（VEGF）在膀胱移行细胞癌中的表达及临床意义。方法：采用免疫组化、ELISA方法对45例膀胱移行细胞癌组织、血浆和10例正常膀胱黏膜组织、30例正常成人血浆中VEGF进行检测分析。结果：VEGF在膀胱移行细胞癌患者中呈高表达，且随分期、分级的增高而增高；膀胱癌手术前患者血浆中VEGF的浓度高于手术后。结论：1．VEGF的表达与膀胱移行细胞癌的病理分级、临床分期及生物学行为有密切关系；2．血浆中VEGF水平可有助于预测膀胱癌患者手术疗效。  相似文献   

10.
Objective:To determine the effect of steroidogenic acute regulatory protein(StAR) overexpression on the levels of adenosine triphosphate(ATP)-binding cassette transporter A1(ABCA1) and ATP-binding cassette transporter G1(ABCG1) in an endothelial cell line(bEnd.3).Methods:The StAR gene was induced in bEnd.3 cells with adenovirus infection.The infection efficiency was detected by fluorescence activated cell sorter(FACS) and fluorescence microscopy.The expressions of StAR gene and protein levels were detected ...  相似文献   

11.
Objective: Large segmental bone defect repair remains a clinical and scientific challenge with increasing interest focusing on combining gene transfection with tissue engineering techniques. The aim of this study is to investigate the effect of connective tissue growth factor (CTGF) on the proliferation and osteogenic differentiation of the bone marrow mesenchymal stem cells (MSCs). Methods: A CTGF-expressing plasmid (pCTGF) was constructed and transfected into MSCs. Then expressions of bone morphogenesis-related genes, proliferation rate, alkaline phosphatase activity, and mineralization were examined to evaluate the osteogenic potential of the CTGF gene-modified MSCs. Results: Overexpression of CTGF was confirmed in pCTGF-MSCs. pCTGF transfection significantly enhanced the proliferation rates of pCTGF-MSCs (P<0.05). CTGF induced a 7.5-fold increase in cell migration over control (P<0.05). pCTGF transfection enhanced the expression of bone matrix proteins, such as bone sialo-protein, osteocalcin, and collagen type I in MSCs. The levels of alkaline phosphatase (ALP) activities of pCTGF-MSCs at the 1st and 2nd weeks were 4.0- and 3.0-fold higher than those of MSCs cultured in OS-medium, significantly higher than those of mock-MSCs and normal control MSCs (P<0.05). Overexpression of CTGF in MSCs enhanced the capability to form mineralized nodules. Conclusion: Overexpression of CTGF could improve the osteogenic differentiation ability of MSCs, and the CTGF gene-modified MSCs are potential as novel cell resources of bone tissue engineering.  相似文献   

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13.
Background:Bone marrow mesenehymal stem cell(MSC)transplantation is a promising strategy in the treatment of myocardial infarction(MI).However,the time for transplanting cells remains controversial.The aim of this study was to find an optimal time point for cell transplantation.Methods:MSCs were isolated and cultured from Sprague-Dawley(SD) rats.MI model was set up in SD rats by permanent ligation of left anterior descending coronary artery.MSCs were directly injected into the infarct berder zone at 1 h,1 week and 2 weeks after MI,respectively.Sham-operated and MI centrel groups received equal volume of phosphate buffered saline(PBS).At 4 weeks after MI,cardiac function Was assessed by echocardiography;vessel density Was analyzed on hematoxylin-eosin stained slides by light microscopy;the apoptosis of cardiomyocytes Was evaluated by terminal deoxynucleotidy1 transferase-mediated dUTP nick end-labeling(TUNEL) assay;the expressions of proteins were analyzed by Western blot.Results:MSC transplantation improved cardiac function.reduced the apoptosis of cardiomyocytes and increased vessel density.These benefits were more obvious in l-week group than in 1-h and 2-week groups.There are more obvious increases in the ratio of bc1-2/bax and the expression of vascular endothelial growth factor(VEGF)and more obvious decreases in the expression of cleaved-caspase-3 in 1-week group than those in other two groups.Conclusion:MSC transplantation was beneficial for the recovery of cardiac function.MSC transplantation at l week post-MI exerted the best effects on increases of cardiac function,anti-apoptosis and angiogenesis.  相似文献   

14.
应用免疫组化方法,比较性地研究了大肠癌组织及其同一患者形态正常大肠粘膜组织中血管内皮细胞生长因子的表达,分析血管内皮细胞生长因子表达与大肠癌发生的年龄、性别、病理分期等因素的关系。结果显示,癌组织与正常大肠粘膜的血管内皮细胞生长因子表达存在明显差异,血管内皮细胞生长因子的表达与大肠癌患者年龄、性别、分化程度等因素不存在相关性,而与Ducks分期存在明显相关性。表明肿瘤血管的生成在大肠癌的生长发展方面起着至关重要的作用,血管内皮细胞生长因子的检测可以作为大肠癌诊断的重要参考指标。  相似文献   

15.
Objective:To explore the feasibility of using regenerated silk fibroin membrane to construct artificial skin substitutes for wound healing, it is necessary to evaluate its cytocompatibility. Methods:The effects of regenerated silk fibroin film on cytotoxicity, adhesion, cell cycle, and apoptosis of L929 cells, growth and vascular endothelial growth factor (VEGF) expression of ECV304 cells, and VEGF, angiopoietin-1 (Ang-1), platelet-derived growth factor (PDGF) and fibroblast growth factor 2 (FGF2) expressio...  相似文献   

16.
Objective： Study blood vessel injury and gene expression indicating vascular endothelial cell apoptosis induced by mannitol with and without administration of anti-oxidative vitamins. Methods： Healthy rabbits were randomly divided into four groups. Mannitol was injected into the vein of the rabbit ear in each animal. Pre-treatment prior to mannitol injection was per- formed with normal saline （group B）, vitamin C （group C） and vitamin E （group D）. Blood vessel injury was assessed under electron and light microscopy. In a second experiment, cell culture specimen of human umbilical vein endothelial cells were treated with mannitol. Pre-treatment was done with normal saline （sample B）, vitamin C （sample C） and vitamin E （sample D）. Total RNA was extracted with the original single step procedure, followed by hybridisation and analysis of gene expression. Results： In the animal experiment, serious blood vessel injury was seen in group A and group B. Group D showed light injury only, and normal tissue without pathological changes was seen in group C. Of all 330 apoptosis-related genes analysed in human cell culture specimen, no significant difference was seen after pre-treatment with normal saline, compared with the gene chip without pre-treatment. On the gene chip pre-treated with vitamin C, 45 apoptosis genes were down-regulated and 34 anti-apoptosis genes were up-regulated. Pre-treatment with vitamin E resulted in the down-regulation of 3 apoptosis genes. Conclusion： Vitamin C can protect vascular endothelial cells from mannitol-induced injury.  相似文献   

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18.
目的：通过康脑液干预观察其对脑缺血再灌注损伤大鼠血管内皮生长因子（vascular endothelial growth factor,VEGF）、脑源性神经生长因子（brain derived neurotrophic factor,BDNF）、基质金属蛋白酶（matrix metalloproteinase-9,MMP-9）表达的影响,探讨康脑液对脑缺血再灌注损伤的保护机制.方法：将雄性SD大鼠随机分为假手术组、脑缺血再灌注模型组及康脑液28.6、14.3、7.15 g·kg-1·d-1剂量组（灌胃给药7 d）,改进Longa等线栓法制备大鼠右侧大脑中动脉阻塞（middle cerebral artery occlusion,MCAO）再灌注模型.于缺血2h后再灌注（分别于再灌注后6h、12h、24 h、72 h、7d处死大鼠）;采用TTC染色法观察大鼠的脑梗死面积;免疫组织化学法观察大鼠脑组织VEGF、BDNF、MMP-9的表达.结果：比较各组缺血再灌注24 h大鼠脑梗死灶面积,发现28.6、14.3 g·kg--1·d-1剂量组较脑缺血再灌注模型组明显减小（P＜0.05）;与脑缺血再灌注模型组相比,28.6、14.3 g·kg--1·d-1剂量组各时间点的VEGF、BDNF表达量明显上调（P＜0.01）,MMP-9表达的阳性细胞明显减少（P＜0.01）,差异有统计学意义.结论：康脑液可促进大鼠局灶性脑缺血后脑组织中VEGF,BDNF的表达,同时抑制脑内MMP-9的表达,缩小脑梗死面积,发挥对神经血管单元（neurovascular unit,NVU）的保护作用,减轻脑缺血再灌注损伤.  相似文献   

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目的：探讨血管内皮生长因子（VEGF）在乳癌中过表达的临床意义。方法：取乳腺腺瘤47例,乳腺癌95例,利用SABC法检测VEGF阳性率。结果：VEGF在腺瘤中阳性率为25.53%（12/47）,在乳癌中阳性率为54.75%（52/95）;在浸润性癌和有淋巴结转移组阳性率明显高于非浸润性组和无淋巴结转移组（P〈0.05）。结论：VEGF过表达提示患者预后不良,检测VEGF对化疗方案选择有指导意义。  相似文献   

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