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AIM:To investigate whether the bcl-2 antisense oligonucleotide increases the sensitivity of HL60 and K562 cell lines to daunorubicin.METHODS:IC50 for HL60 and K562 was determined with MTT method, the expression levels of Bcl-2 protein were assayed by immunofluorescence using fluoresce isothiocyanate labeling. In addition, apoptosis was detected by morphological observation and flow cytometric analysis of DNA fragmentation.RESULTS:It was found that the two oligonucleotides directed against the coding region and the translation initiation of bcl-2 mRNA, combined respectively with daunorubicin, inhibited expression of bcl-2 protein, increased apoptosis in HL60 and K562 cells, and decreased IC50 of daunorubicin significantly (P<0.05). Compared to the antisense oligonucleotide directed against the translation initiation of bcl-2 mRNA, the antisense oligonucleotide directed against the coding region showed stronger effects in the aspects of increasing the sensitivity of HL60 cells to daunorubicin (P<0.05).CONCLUSIONS:These two antisense sequences in the translation initiation and the coding region of bcl-2 mRNA increased the sensitivity of HL60 and K562 cell lines to daunorubicin in a sequence-specific manner. 相似文献
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CHEN Chun-yan JIA Ji-hui PAN Xiang-lin ZHANG Qi WANG Juan-dong ZHOU Ya-bin 《园艺学报》2004,20(7):1183-1186
AIM: To study the signal transduction pathway of apoptosis initiation induced by homoharringtonine in HL-60 cells. METHODS: After establishing the model of apoptosis initiation induced by homoharringtonine in HL-60 cells, at the point of apoptosis initiation, molecular caspase-3, Bcl-2, Bax and Fas/FasL were measured with flow cytometry and transmission electron microscope. ERK2 and P38 expression in HL-60 cells were detected by using immunohistochemistry. RESULTS: The model of apoptosis initiation induced by homoharringtonine was established in HL-60 cells. At the point of apoptosis initiation, upregulation of caspase-3 and decrease in Bcl-2/Bax were observed. However, the expression of Fas/FasL did not significantly change. ERK2 expression decreased and P38 expression increased. CONCLUSIONS: Caspase-3, Bcl-2, Bax and mitogen activated protein kinase pathways were involved in signal transduction of apoptosis initiation induced by homoharringtonine in HL-60 cells. 相似文献
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IntroductionCystic echinococcosis (CE) is a chronic zoonotic disease caused by the larval stage of Echinococcus granulosus (E. granulosus), which affects domestic and wild carnivores as the definitive host and ungulates as intermediate hosts. In intermediate hosts, both Th1 and Th2 cells are involved in the immune responses to an echinoccocal infection. This study aimed to investigate production of IL-4, IL-10, and IFN-γ cytokines in peripheral blood mononuclear cells (PBMCs) of CE patients before and after surgical treatment.MethodsTo evaluate cytokine production in response to E. granulosus antigens, we investigated IL-4, IL-10, and IFN-γ production in PBMCs of 20 CE patients in response to hydatid cyst fluid antigen (HCF-Ag) before and after surgical treatment using ELISA.ResultsThe mean IL-4 production from HCF-Ag stimulated PBMCs was significantly decreased (p < 0.05), while IFN-γ was significantly increased in HCF-Ag stimulated PBMCs in patients after surgery (p = 0.005).Furthermore, our results showed that there is no significant difference between IL-10 production in patients before and after treatment (p = 0.562).ConclusionsOur data Indicated production of IL-4 in cultured PBMCs of CE patients stimulated with HCF-Ag was decreased significantly. While, production of IFN-γ was increased significantly in responses to HCF Ag after surgery. We concluded that the evaluation of IL-4 and IFN-γ in HCF-Ag stimulated PBMCs of CE patients should be considered as a useful marker in the follow up of patients with cystic echinococcosis. 相似文献
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为探究60Co-γ射线辐射处理种子对大花紫薇生长发育中光合效率的影响,以大花紫薇种子为试验材料,以不同60Co-γ射线辐射剂量(0、20、60、100、140、180 Gy)进行辐射处理,测量不同处理生长发育过程中叶绿素及光合指标的变化,研究其对紫薇光合系统的影响。结果表明:20、60 Gy处理较对照和其他处理叶绿素质量分数更高,更有利于叶片进行光合作用;60、100 Gy处理较对照和其他处理潜在光合速率和最大光合效率更好;各时期光合性能指数与综合性能指数均呈现先上升后下降的趋势,但随时间的增加整体呈现下降的趋势,60 Gy较其他处理性能指数高。由此得出,60 Gy辐射处理有利于大花紫薇光合色素的产生与积累,较好的增加电子传递效率,有利于光合系统的运转和能量的积累。 相似文献
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