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91.
Background and aim: Lung cancer is one of leading malignant tumor worldwide with a high mortality rate. A new therapy target, enhancer of polycomb1 (EPC1) knocked down by short hairpin RNA (shRNA) interference technology, for lung cancer was established to investigate its effects on lung cancer in present study. Methods: RNA interference technology was applied to down-regulate the expression of EPC1 by specific-shRNA with lentivirus vector in neoplastic human alveolar basal epithelial cells (A549 cells). The survival rate and apoptosis were respectively measured by MTT and Flow Cytometry to evaluate the effects of shRNA EPC1 on cells. Mice xenografts of HCT116 cells with shRNA EPC1 were also established to assess the effect on tumor growth. The levels of AKT and p65 were detected by western blotting. Results: The down-regulation of EPC1 by specific-shRNA with lentivirus vector was significantly decreased the survival rate and apoptosis of A549 cells, and the tumors in EPC1 shRNA transfection group had a significant lower size and weight compared with the ones with control shRNA. The protein expression of p-AKT and p65 was reduced by EPC1 shRNA in both in vitro and in vivo experiments. Conclusion: Silencing EPC1 by shRNA technology had the inhibition effects on cell proliferation and tumor growth in lung cancer, which provided a new potential target for treatment of cancers.  相似文献   
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Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans.  相似文献   
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目的研究嗜酸乳杆菌对人舌癌细胞Tca8113增殖及细胞周期的影响。方法体外培养Tca8113细胞,分别将不同稀释度(原液和4、16倍稀释)的嗜酸乳杆菌上清液、灭活菌液和无细胞提取物与Tca8113细胞共培养,采用倒置显微镜观察细胞形态并行细胞计数,磺酰罗丹明B(SRB)法测定细胞增殖率,流式细胞术分析嗜酸乳杆菌各组分对Tca8113细胞增殖及细胞周期的影响,激光扫描共聚焦显微镜(CLSM)检测细胞内自由基和Ca2+含量。结果嗜酸乳杆菌各组分作用于Tca8113细胞48 h后,在倒置显微镜下观察,细胞由菱形、多角形、铺路石状变为细长形。细胞计数与SRB实验分析:在不同稀释度同一培养时间与不同培养时间同一稀释度培养条件下,嗜酸乳杆菌各组分均可明显抑制Tca8113细胞增殖,抑制力随稀释度增加而降低,随培养时间延长而增强。流式细胞术分析:嗜酸乳杆菌各组分作用Tca8113细胞48 h后,细胞增殖指数降低(P<0.01)。CLSM检测:嗜酸乳杆菌各组分作用Tca8113细胞48 h后细胞内自由基和Ca2+含量均升高(P<0.01)。结论嗜酸乳杆菌代谢产物、灭活菌液、无细胞提取物均可抑制Tca8113细胞增殖,可能与菌体及其代谢产物引起细胞内自由基含量增多、Ca2+超载有关。  相似文献   
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Purpose

Docetaxel plus capecitabine, a commonly used chemotherapeutic regimen for metastatic breast cancer (MBC), is highly variable in its effectiveness. We aimed to investigate whether allelic variants of cytochrome P450 (CYP450) affected objective response, progression-free survival (PFS), and overall survival (OS) in MBC.

Patients and methods

79 SNPs in CYP450, whose minor allele frequency were ≥10%, were genotyped in 69 MBC patients who were treated with docetaxel plus capecitabine. Pearson’s χ2 test or Fisher’s exact test was used to investigate the influence of SNPs on objective response as appropriate. Log-rank test was used to assess the association between SNPs and survival outcomes.

Results

There is no significant association between polymorphisms and both objective response and OS. Only one SNP, CYP1A1 rs1048943 A>G (Ile462Val), was significantly associated with PFS (P?=?0.0003). Multivariate analysis confirmed its prognostic significance for PFS (P?=?0.004).

Conclusion

CYP1A1 rs1048943 A>G (Ile462Val) polymorphism is a potential prognostic marker for survival outcome after docetaxel plus capecitabine chemotherapy in MBC patients. However, confirmatory study is needed to validate this finding.  相似文献   
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