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991.
AIM: To study the role of translationally controlled tumor protein (TCTP) in the proliferation, migration and invasion of phosphatase of regenerating liver-3(PRL-3)-promoted colon cancer cells.METHODS: The vectors pAcGFP-C3 and pAcGFP-C3-PRL-3 were constructed and transfected into the colon cancer cell line LoVo.LoVo-PRL-3 cells stably expressing PRL-3 and LoVo-control cells were established. The expression levels of PRL-3 and TCTP in both cells were detected by Western blotting and real-time PCR. The specific siRNA sequence for TCTP mRNA and control-siRNA were synthesized and transfected into the LoVo-PRL-3 cells. TCTP expression at mRNA and protein levels in LoVo-PRL-3 was detected by Western blotting and real-time PCR 24 h, 48 h and 72 h after transfection. The proliferation, migration and invasion abilities of LoVo-control cells, LoVo-PRL-3 cells, TCTP-siRNA and control-siRNA cells were detected by CCK-8 assay and the method of Transwell cell culture chambers.RESULTS: The expression of TCTP at mRNA and protein levels in LoVo cells was significantly increased after PRL-3 transfection (P<0.05). TCTP mRNA was significantly inhibited 24 h, 48 h and 72 h after transfection of TCTP-siRNA (P<0.01). TCTP protein was also significantly inhibited 48 h and 72 h after transfection (P<0.01). Compared with LoVo-control cells, the proliferation, migration and invasion abilities of LoVo-PRL-3 cells were significantly enhanced (P<0.05). However, lowering the up-regulated expression of TCTP in LoVo-PRL-3 cells inhibited the proliferation, migration and invasion abilities (P<0.05). CONCLUSION: PRL-3 promotes proliferation, migration and invasion of colon cancer cells by up-regulating the TCTP expression. siRNA targeting TCTP may be an effective method for prevention and treatment of colon cancer cell metastasis. 相似文献
992.
DENG Yu-jun FU Yong-heng TAN Ning ZENG Hong-ke SHAN Zhi-xin LIN Qiu-xiong LI Xiao-hong DONG Xiao-li YU Xi-yong YANG Min TAN Wei-ping SU Jian 《园艺学报》2011,27(2):412-416
AIM: To establish and evaluate a rat model of heart ischemia-reperfusion injury in vivo. METHODS: Seventy-two male Sprague-Dawley rats weighing(250±50)g were randomly divided into sham operation group(sham), ischemia-reperfusion group(I/R) and normal group. The animals were anesthetized and heparinized. Myocardial ischemia-reperfusion was induced by ligating the left anterior descending coronary artery with "U-shape tube" for 35 min followed by 120 min or 240 min reperfusion in vivo. The heart infarct size was measured by triphenyltetrazolium chloride(TTC) staining. The myocardial cell apoptotic index was determined by the method of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling(TUNEL). Immunohistochemical method was used to detect the expression of Bcl-2 and Bax in rat ischemia myocardium. The blood level of MB isoenzyme of creatine kinase(CK-MB),cardiac troponin I(cTnI),nitric oxide(NO),malondialdehyde(MDA), total superoxide dismutase(T-SOD)and glutathione peroxidase(GSH-Px) were detected after reperfusion for 2 h and 4 h. RESULTS: Compared with normal group and sham group, there were obvious changes of ST-T segment and Q wave in the electrocardiogram of I/R group. The blood level of CK-MB, cTnI, NO, MDA and GSH-Px in I/R group increased(P<0.05,P<0.01) after reperfusion for 2 h and 4 h, and the blood level of T-SOD in I/R group after reperfusion for 2 h and 4 h also increased(P<0.05). The heart infarct size in I/R group was the largest as compared to other groups. Among these groups, the apoptotic index of I/R group was the highest and the Bcl-2/Bax ratio in I/R group decreased(P<0.01).CONCLUSION: The rat model of heart ischemia-reperfusion injury in vivo can be successfully established with the "U-shape tube". There are obviously changes of heart infarct size, blood level of CK-MB, cTnI, NO, MDA, T-SOD and GSH-Px, myocardial apoptotic index and Bcl-2/Bax ratio between I/R rats and control animals. 相似文献
993.
AIM: To investigate the effects of lenalidomide alone or combined with bortezomib on induction of apoptosis in multiple myeloma(MM) KM3 cells.METHODS: The KM3 cells were treated with lenalidomide alone or combined with bortezomib. The number of viable cells was determined by trypan blue exclusion. Apoptotic cells were simultaneously stained with annexin V-FITC and PI and determined by flow cytometry. RT-PCR was used to examine the level of p65 mRNA. Western blotting was used to examine the protein levels of P65, pP65, caspase-3,-8, -9, and poly (ADP-ribose) polymerase (PARP). RESULTS: Lenalidomide-inhibited the cell growth and induced apoptosis of KM3 cells. The mechanism responsible for lenalidomide-mediated inhibition was via NF-κB and activation of caspase-mediated induction of apoptosis. A synergistic effect was observed when combination of lenalidomide with bortezomib was used. CONCLUSION: Lenalidomide inhibits the growth and induces apoptosis in KM3 cells. There is a synergistical effect when combination of lenalidomide with bortezomib is in use. 相似文献
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995.
对云南农垦橡胶产业现状的思考 总被引:1,自引:0,他引:1
报道了对西双版纳农垦天然橡胶产业体制改革中橡胶加工业的现状、问题的观察和思考,进而对农垦橡胶加工业的调整提出建议。 相似文献
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999.
以清水为对照,于颖花开放前对杂交籼稻亲本"特A"、"培矮64S"和"9311"喷施MeJA(茉莉酸甲酯)和MeJA(茉莉酸甲酯) BA(6-苄基腺嘌呤),比较两处理对颖花开放的调控差异。MeJA和MeJA BA对"特A"和"培矮64S"颖花开放的诱导效应明显,提早了花时,提高了颖花开放的集中度,缩短了开花历期,对"9311"花时和花期的调控也有一定效果,两处理在花时和花期的效应上基本一致;MeJA使3个杂交亲本材料颖花开放角度和颖尖距离均有所缩小,MeJA BA则略有增大;MeJA和MeJA BA对杂交亲本材料的株高、剑叶长、外露颈穗长无明显影响。并讨论了MeJA与BA在杂交籼稻制种上的联合应用。 相似文献
1000.
Heavy Metal Accumulation in Plants on Mn Mine Tailings 总被引:9,自引:0,他引:9
The Xiangtan Manganese (Mn) Mine in the middle of Hunan Province, China, has been mined since 1913 with mine tailings including excavated wastes, wastewater, and smelting wastes. A survey was conducted on the Mn mine tailing soils and eight plants on the Mn mine tailings. The concentrations of soil Mn, Pb, and Cd and the metal-enrichment traits of these eight plants were analyzed simultaneously. Exceptionally high concentrations of these three metals were found in the soils, especially on the tailing dam. Each plant investigated in this study accumulated the three heavy metals, but no hyperaccumulator of these metals was found. However, analysis indicated that Poa pratensis Linn., Gnaphalium affine D. Don, Pteris vittata L., Conyza canadensis (L.) Cronq., and Phytolacca acinosa Roxb. possessed specially good metalenrichment and metal-tolerant traits. P. pratensis, G. affine, and P. vittata were Pb-tolerant plants; and C. canadensis, P. pratensis, and G. affine were Cd-tolerant plants. P acinosa had a great tolerance to Mn, and it was a valuable plant for on-site phytoremediation. Phragmites communis Trin. was found to have high metal tolerance and economic benefit as a raw material for paper and should be considered for soil remediation. G. affine and C. canadensis had excessive accumulation of Mn and could be useful in phytoremediation. However, although P. pratensis was a good accumulator, it was not a suitable plant for soil remediation because its biomass was too little. 相似文献