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Objective: To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide (G4PAMAMNEGFASODN) compound on the expressions of vascular endothelial growth factor (VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods: We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability, in vitro transfection efficiency and toxicity, and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results: The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10, it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%, significantly higher than that of the liposome group (P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion: With a low toxicity, high safety, and high transfection rate, G4PAMAMNEGFASODN could be a promising gene vector. Specifically, it inhibits VEGF gene expression efficiently, laying a basis for further in vivo animal studies.  相似文献   

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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   

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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   

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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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血管内皮生长因子家族及其受体   总被引:1,自引:0,他引:1  
血管内皮生长因子(VEGF)家族包括VEGF—A,-B,—C,—D,—E和胎盘生长因子(PIGF),都与同型的酪氨酸激酶受体VEGFR—1(Fltl),VEGFR—2(KDR/Flk1)和/或VEGFR—3(Flt4)结合。本文综述血管内皮生长因子家族及其受体在肿瘤血管生成、淋巴管生成及肿瘤转移中的作用。  相似文献   

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In this study, we examined the expression of inducible nitric oxide synthase (iNOS) and vascular endothelial growth factor (VEGF) by immunohistochemical staining in 76 tissue sections collected from hepatocellular carcinoma (HCC) patients undergoing hepatectomy. Microvascular density (MVD) was determined by counting endothelial cells immunostained using anti-CD34 antibody. We performed DNA-flow cytometric analyses to elucidate the impact of iNOS and VEGF expression on the cell cycle of HCC. Most of the HCC cells that invaded stroma were markedly immunostained by iNOS antibody. The iNOS stain intensity of the liver tissue close to the tumor edge was stronger than that of HCC tissue, and the strongest was the hepatocytes closer to the tumor tissue. However, iNOS expression in 10 normal hepatic samples was undetectable. VEGF positive expression ratio was 84.8% in iNOS positive expression cases, and the ratio was 35.3% in negative cases. There was significant correlation (P=0.000) between iNOS and VEGF expression. Moreover, iNOS expression was significantly associated with bcl-2 and MVD, but without p53 expression. DNA-flow cytometric analyses showed that combined expression of iNOS and VEGF had significant impact on the cell cycle in HCC. PI (Proliferating Index) and SPF (S-phase fraction) in the combined positive expression of iNOS and VEGF group was significantly higher than that in the combined negative group. The present findings suggested that iNOS expression was significantly associated with angiogenesis, bcl-2 and cell proliferation of HCC. Project supported in part by the National Ninth-Five-Years Project Fund (No. 96909121), China  相似文献   

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INTRODUCTIONNitricoxide (NO) ,ashorthalf liferadical,ishighlyreactive ,andisinvolvedinmanybio logicalprocesses,Itseemstoplayanimporta  相似文献   

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近代湖丝外贸的回顾与思考   总被引:1,自引:0,他引:1  
近代湖丝外贸迅速崛起于中国五口通商之时,急剧衰落于第一次世界大战之后。通过对近代湖丝外贸盛衰的考察,得出以下结论:对外贸易要持续发展,国家的强大繁荣是关键;只有把握机遇,适应形势才能求得生存与发展;要在激烈的市场竞争中不被淘汰,必须跟上时代的步伐,进行技术革新,不断提高产品质量。  相似文献   

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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   

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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   

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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   

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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   

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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   

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Vascular endothelial growth factor (VEGF) is the main regulator of physiological angiogenesis during embryonic development, bone growth, and reproductive function, and it also participates in a series of pathological changes. Traditional Chinese medicine (TCM), with a history of more than 2000 years, has been widely used in clinical practice, while the exploration of its mechanisms has only begun. This review summarizes the research of recent years on the influence of TCM on VEGF. It is found that many Chinese medicines and recipes have a regulatory effect on VEGF, indicating that Chinese medicine has broad prospects as a complementary and alternative therapy, providing new treatment ideas for clinical applications and the theoretical basis for research on the mechanisms of TCM.  相似文献   

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INTRODUCTION Transgenic technology developed over the 20years, has become a common tool widely applied tolivestock species because it is technically quitesimple, requiring only the injection of ‘naked’DNA into the nucleus of a fertilized eggs (Hammeret al., 1985; Suraokar and Bradley, 2000). Howeverthis technique has limitations in that the injectedDNA integrates randomly into the genome and thuscould not be expressed in the desired tissue or at theappropriate level. More impor…  相似文献   

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The long-arm and short-arm genes of fibroin light chain (L-chain) of silkworm, Bombyx Mori L., and the gene of human acidic fibroblast growth factor were cloned respectively and subsequently inserted into a transfer vector pVL1392 used as a tool to target the L-chain region of the silkworm genome. Genomic DNA from their offsprings was extracted and the expected targeting was detected using polymerase chain reaction and DNA sequencing, as well as protein analysis. The results showed that positive events occurred and that the FGF gene was integrated into the L-chain locus through homologous recombination.  相似文献   

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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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