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摘要:目的 探讨白花蛇舌草-半枝莲药对组分对结肠腺癌Lovo细胞增殖、侵袭、迁移和凋亡的影响及作用机制。方法 将白花蛇舌草、半枝莲按质量1∶1进行3次煎煮,获得水提物,后取适量浸膏用石油醚回流脱脂,再以乙酸乙酯进行多次萃取,获得白花蛇舌草-半枝莲药对组分,并计算得率。实验分为对照组(正常培养Lovo细胞)、白花蛇舌草-半枝莲药对组分低剂量组(10 mg/L)、中剂量组(30 mg/L)及高剂量组(50 mg/L)。通过噻唑蓝比色法(MTT)检测各组细胞培养24、48、72 h后的增殖抑制率。各组细胞培养48 h后,流式细胞仪检测细胞周期分布;Transwell实验检测细胞侵袭能力;划痕实验检测细胞迁移能力;TUNEL法检测细胞凋亡情况;Western blot法检测Grb2相关结合蛋白1(Gab1)、血管内皮生长因子受体2(VEGFR-2)、磷脂酰肌醇3-激酶(PI3K)、苏氨酸激酶(Akt)、基质金属蛋白酶-9(MMP-9)、B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)蛋白表达情况。结果 化学萃取后的白花蛇舌草-半枝莲药对中主要含有对羟基苯乙酮、野黄芩苷、木犀草素和芹菜素4种化合物,组分得率为0.61%。与对照组相比,低、中、高剂量组细胞增殖抑制率升高,G1期肿瘤细胞比例增加,细胞凋亡指数增高,侵袭细胞数和划痕闭合率明显减小(均P<0.05),细胞中Gab1、VEGFR-2、PI3K、Akt、MMP-9、Bcl-2蛋白表达降低,Bax表达升高(均P<0.05),且存在剂量依赖性。结论 白花蛇舌草-半枝莲药对组分可抑制结肠腺癌Lovo细胞的增殖,降低其迁移和侵袭能力,诱导细胞凋亡,其机制可能与抑制Gab1/VEGFR-2/PI3K/Akt信号通路活化有关。  相似文献   
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Over the past years, the multidisciplinary character of the international Computer-Aided Surgery around the Head (CAS-H) symposium has advanced many medical technologies, which were often adopted by industry. In Bern, the synergetic effects of the CAS-H symposium have enabled many experiences and developments in the area of computer-aided surgery. Planning and simulation methods in the areas of craniomaxillofacial surgery and otorhinolaryngology were developed and tested in clinical settings. In the future, further CAS-H symposia should follow, in order to promote the possibilities and applications of computer-assisted surgery around the head.  相似文献   
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BACKGROUND: Approximately 3% of patients exposed to iodinated contrast media develop delayed hypersensitivity reactions. OBJECTIVE: We wanted to better understand the molecular basis of contrast media cross-reactivity. METHODS: Cross-reactivity was assessed by skin testing and measurement of T-cell activation (CD69 upregulation) and proliferation ((3)H-thymidine uptake, 5,6-carboxyfluorescein diacetate succinimidyl ester staining) of PBMCs, T-cell lines, and T-cell clones of 2 patients with delayed hypersensitivity reactions to iohexol and iomeprol, respectively. Thirteen different contrast media and potassium iodide were compared. RESULTS: Skin testing and analyses of PBMCs, T-cell lines, and clones showed broad cross-reactivity in both patients. Broad as well as more restricted cross-reactivity patterns were found in iohexol-specific and iomeprol-specific CD4(+) T-cell clones, whereas 1 iomeprol-specific CD8(+) T-cell clone showed no cross-reactivity at all. The reactivity to equimolar concentrations of iohexol and its dimer iodixanol was very similar, suggesting that the dimer was not more stimulatory than its monomer. Consistently low reactivity to iobitridol was found in both patients, but never to iodide. A frequency analysis of contrast medium-specific peripheral T cells gave values between 0.6 % (iomeprol) and 0.05 % (iobitridol). CONCLUSION: Clinically observed cross-reactivity between different contrast media is a result of the presence of contrast media-specific T cells, some of which show a broad cross-reactivity pattern. Iodide ions, known to be present at low concentration in contrast media solutions, do not seem to be the causative moiety. CLINICAL IMPLICATIONS: Detailed in vitro analysis might help identify noncross-reactive contrast media.  相似文献   
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ObjectiveTo evaluate the association between bezafibrate, a drug used to treat hypertriglyceridemia, and long-term cancer incidence in patients with coronary artery disease (CAD).Patients and MethodsThe study comprised 2980 patients with CAD (mean age, 60 years; 2729 [91.6%] men) who were free of cancer and were enrolled in the Bezafibrate Infarction Prevention study, a double-blind trial conducted between May 1, 1990, and January 31, 1993, in 18 cardiology departments in Israel. Patients randomized to receive 400 mg of bezafibrate (n=1486) or placebo (n=1494) daily for a median of 6.2 years (range, 4.7-7.6 years) were followed up for incidence of cancer through the Israeli National Cancer Registry and all-cause death through the Population Registry of the State of Israel until December 31, 2013. Cox proportional hazards and Fine and Gray survival models were used to assess the bezafibrate-cancer association.ResultsClinical characteristics and laboratory values were well balanced between the 2 groups at the study entry. Over a median follow-up of 22.5 years (range, 21.2-23.9 years), cancer developed in 753 patients. With death considered a competing event, the cumulative incidence of cancer at the end of the follow-up was lower in the bezafibrate vs the placebo group (23.9%; 95 CI, 21.9%-26.1% vs 27.2%; 95 CI, 25.1%-29.4%; P=.04). The hazard ratio for cancer in the bezafibrate vs placebo groups was 0.86 (95% CI, 0.74-0.99). In mediation analysis, the association between bezafibrate treatment and cancer incidence was not sensitive to adjustment for on-trial lipid levels but was attenuated on adjustment for on-trial fibrinogen levels.ConclusionBezafibrate treatment is associated with reduced risk of cancer among patients with CAD. Fibrinogen, but not lipid lowering, is linked to this association.  相似文献   
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