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91.
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Objective: To investigate the cell cycle changes of hepatoma cells and the role of antisense oligonucleotide targeting bFGF. Methods: Inhibition of bFGF protein expression was investigated by confocal microscopy analysis and Western blot in the best condition of transfecting antisense oligonucleotide targeting bFGF. Cell cycle and apoptosis were detected with flow cytometry analysis. Results: Treatment with antisense oligonucleotide of bFGF not only reduced the expression of bFGF by confocal microscopy and Western blot analysises, but also increased the apoptosis of HepG2 cells ( P 〈 0.01). Conclusion: bFGF may take part in apoptosis regulation of hepatoma cells and be used as a target of hepatocellular carcinoma therapy.  相似文献   
94.

Background

Motherwort has been used as medicinal herb for many years in both China and Europe. In particular, Chinese motherwort has been commonly used to treat disorders of mammary gland in Chinese traditional medicine (TCM). Chinese motherwort aqueous extract (MAE) was previously reported to have anti-cancer activity in breast cancer cells with low potency (IC50s in a range of 8–40 mg/mL). However, treatment of motherwort ethanol extract in vivo markedly suppressed the development of uterine adenomyosis and mammary cancers in mice. Therefore, anti-cancer activity of Chinese motherwort, especially in a form of ethanol extract, needs to be confirmed further at cellular level.

Materials and methods

Aerial part of Chinese motherwort (Leonurus japonicus Houtt) dry powder is extracted with 70% ethanol and the chemical components were characterized with HPLC finger print as well as mass spectrometry. Cytotoxicity of the motherwort aqueous ethanol extract (MAEE) was analyzed with MTT assay on ER negative MDA-MB-231 and ER positive MCF-7 human breast cancer cell lines. Hoechst 33342 staining and flow cytometry were used to verify whether the cell death induced by MAEE is apoptosis in nature. Cell cycle status of MAEE treated cells were analyzed with flow cytometry.

Results

Our results showed that MAEE caused cell death in a dose-dependent and time-dependent fashion in both ER positive and negative breast cancer cells. Morphology, Hoechst 33342 staining and flow cytometry evidence all indicated the cell death is not in an apoptotic nature. Furthermore, low concentrations of MAEE caused cell cycle arrest at G2/M phase.

Conclusions

These data suggest that Chinese motherwort aqueous ethanol extract may effectively inhibit the proliferation of breast cancer cells through mechanisms of both cytotoxicity and cell cycle arrest. The cellular effects of MAEE are non-apoptotic and ER independent on breast cancer cells.  相似文献   
95.
直视下尿道内切开术后再次狭窄20例分析   总被引:2,自引:0,他引:2  
目的对直视下尿道内切开术(DVIU)的术后疗效进行分析,重新认识DVIU的手术适应证,探索降低DVIU术后再次狭窄的方法。方法回顾性分析2004年1月至2009年4月78例尿道狭窄行DVIU术临床资料,对DVIU术后再次尿道狭窄病例进行分析,术前狭窄长度≤1.0㎝15例,1.1~2㎝42例2,~2.5㎝15例,≥2.5㎝6例,狭窄部位后尿道42例、前尿道36例,尿道球部2例。结果 DVIU1次成功70例,2次成功8例,术中加用电切12例,术后留置尿管时间3天~3月。术后随访1年,再次发生尿道狭窄20例,其中术后3月9例,术后半年11例。结论选择≤1㎝的尿道狭窄作为手术适应证,术中轻柔操作,合理选择留置尿管时间等,能降低DVIU术后再次尿道狭窄的复发率,应当有选择性地应用DVIU。  相似文献   
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97.
The amyloid precursor protein (APP) metabolism is central to pathogenesis of Alzheimer's disease (AD). Parenchymal amyloid deposits, a neuropathological hallmark of AD, are composed of amyloid-beta peptides (Abeta). Abeta derives from the amyloid precursor protein (APP) by sequential cleavages by beta- and gamma-secretases. Gamma-secretase cleavage releases the APP intracellular domain (AICD), suggested to mediate a nuclear signaling. Physiologically, AICD is seldom detected and thus supposed to be rapidly degraded. The mechanisms responsible of its degradation remain unknown. We used a pharmacological approach and showed that several alkalizing drugs induce the accumulation of AICD in neuroblastoma SY5Y cell lines stably expressing APP constructs. Moreover, alkalizing drugs induce AICD accumulation in naive SY5Y, HEK and COS cells. This accumulation is not mediated by the proteasome or metallopeptidases and is not the result of an increased gamma-secretase activity since the gamma-secretase cleavage of Notch1 and N-Cadherin is not affected by alkalizing drug treatments. Altogether, our data demonstrate for the first time that alkalizing drugs induce the accumulation of AICD, a mechanism likely mediated by the endosome/lysosome pathway.  相似文献   
98.
目的 探讨CyclinD1,P16在胶质瘤复发前后表达改变及其意义。方法 采用免疫组织化学LsABC法对 4 5例复发胶质瘤瘤组织、瘤旁脑组织和 10例正常脑组织CyclinD1,P16蛋白表达进行检测 ,统计分析CyclinD1,P16表达水平与胶质瘤分级、肿瘤复发的关系。结果 正常脑组织 ,瘤旁脑组织和胶质瘤组织CyclinD1表达依次升高 ,而P16的表达依次下降 ;肿瘤复发CyclinD1表达增强 ,P16的表达减弱。结论 CyclinD1与P16的表达与胶质瘤恶性进程和复发密切相关。  相似文献   
99.
Several epidemiological investigations indicate that cancer survivors have a lower risk for Alzheimer’s disease (AD) and vice versa. However, the associations between plasma amyloid-beta (Aβ) levels with cancer remain largely unknown. In this case–control study, 110 cancer patients, 70 AD patients, and 70 age- and gender-matched normal controls were recruited. The cancer types include esophagus cancer, colorectal cancer, hepatic cancer, and lung cancer, all of which were reported to be associated with a lower risk for AD. Plasma levels of Aβ40, Aβ42, common pro-inflammatory cytokines, IL-1β, IL-6, TNF-α, IFN-γ, anti-inflammatory IL-4, chemokines, and cytokines MCP-1 were measured with enzyme-linked immunosorbent assay (ELISA) kits. Plasma levels of Aβ40 and Aβ42 in all cancer patients were higher than that in normal controls. More specifically, hepatic cancer patients exhibited significantly higher plasma Aβ levels. No significant difference in plasma Aβ levels was found between chemotherapy and no chemotherapy subgroups. Plasma Aβ levels were not significantly correlated with pro-inflammatory cytokines, anti-inflammatory, chemokines, and cytokines. Peripheral Aβ levels increased in cancer patients, especially in patients with hepatic cancer, independent of chemotherapy and inflammation. Further verification is required for the association between plasma Aβ and cancer.  相似文献   
100.
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