AIM: To synthesize three small-interference RNAs (siRNAs) by T7 RNA polymerase-catalyzed reaction, and to investigate their efficacy on modulating the expression of serine/threonine kinase Pim-2 in human colon cancer ...AIM: To synthesize three small-interference RNAs (siRNAs) by T7 RNA polymerase-catalyzed reaction, and to investigate their efficacy on modulating the expression of serine/threonine kinase Pim-2 in human colon cancer cell line.METHODS: siRNA Ⅰ,Ⅱ and Ⅲ were synthesized by T7 RNA polymerase-directed in vitro transcription, then transfected into human colon cancer cells SW-480. After incubation for 6 h at 37℃, 100 mL/L FBS in RPMI 1640 was substituted in each well. After the transfection was repeated twice to three times in each kind of siRNA, hPim-2 mRNA and protein expression were measured by RT-PCR and Western blotting, respectively.RESULTS: Compared to the control group, after transfected for 48 h with hPim-2 siRNA Ⅰ, Ⅱ and Ⅲ, the relative inhibition rates of hPim-2 mRNA expression in colon cancer cell swere 65.4% (P<0.05), 46.2% (P<0.05) and 56.1% (P<0.05),respectively. The protein level of hPim-2 was decreased at 72 h compared to the untransfected cells. The relative inhibition percentages of hPim-2 protein by siRNA Ⅰ, Ⅱ, Ⅲ were 61.6% (P<0.05), 45.8% (P<0.05) and 55.6% (P<0.05),respectively.CONCLUSION: The in vitro transcribed siRNAs can be useful for silencing oncogene hPim-2 expression specifically and efficiently. This may open a new path toward the use of siRNAs as a gene-specific therapeutic tool.展开更多
Elemental carbon?EC) is a C-rich, O-H-S-N-depleted substance that is necessarily produced in the process of combustion. Due to the logn-term use of fire by cave-inhabiting ape-men, considerable amounts of 揺lemen-tal ...Elemental carbon?EC) is a C-rich, O-H-S-N-depleted substance that is necessarily produced in the process of combustion. Due to the logn-term use of fire by cave-inhabiting ape-men, considerable amounts of 揺lemen-tal carbon?would be necessarily left behind in the corre-sponding strata inside the cave. The sepaation of EC was effected by the chemical method and the contents of carbon were determined on an element analyser and a self-made measuring system. The concentration of Ec in the hearth,the exhibited ash samples collected from near the hearth un-earthed in the 1930s, and the three samples of accumulated material collected from the tenth bed are 43.74%, 1.77%,3.88%,1.87% and 1.11%,respectively; those of the equivalent samples from the tenth bed outside the cave and samples from the fourth and seventh beds are at least one order of magnitude lower than the former抯. The above re-sults show that the sampling location of the tenth bed may be close to the hearth. Sampling over a wider range may lead to the finding of a location where the concentrations of EC are corresponding to the maximum values of EC in the hearth. The determination and study of EC may provide new evi-dence for the use of fire by Peking Man.展开更多
文摘AIM: To synthesize three small-interference RNAs (siRNAs) by T7 RNA polymerase-catalyzed reaction, and to investigate their efficacy on modulating the expression of serine/threonine kinase Pim-2 in human colon cancer cell line.METHODS: siRNA Ⅰ,Ⅱ and Ⅲ were synthesized by T7 RNA polymerase-directed in vitro transcription, then transfected into human colon cancer cells SW-480. After incubation for 6 h at 37℃, 100 mL/L FBS in RPMI 1640 was substituted in each well. After the transfection was repeated twice to three times in each kind of siRNA, hPim-2 mRNA and protein expression were measured by RT-PCR and Western blotting, respectively.RESULTS: Compared to the control group, after transfected for 48 h with hPim-2 siRNA Ⅰ, Ⅱ and Ⅲ, the relative inhibition rates of hPim-2 mRNA expression in colon cancer cell swere 65.4% (P<0.05), 46.2% (P<0.05) and 56.1% (P<0.05),respectively. The protein level of hPim-2 was decreased at 72 h compared to the untransfected cells. The relative inhibition percentages of hPim-2 protein by siRNA Ⅰ, Ⅱ, Ⅲ were 61.6% (P<0.05), 45.8% (P<0.05) and 55.6% (P<0.05),respectively.CONCLUSION: The in vitro transcribed siRNAs can be useful for silencing oncogene hPim-2 expression specifically and efficiently. This may open a new path toward the use of siRNAs as a gene-specific therapeutic tool.
文摘Elemental carbon?EC) is a C-rich, O-H-S-N-depleted substance that is necessarily produced in the process of combustion. Due to the logn-term use of fire by cave-inhabiting ape-men, considerable amounts of 揺lemen-tal carbon?would be necessarily left behind in the corre-sponding strata inside the cave. The sepaation of EC was effected by the chemical method and the contents of carbon were determined on an element analyser and a self-made measuring system. The concentration of Ec in the hearth,the exhibited ash samples collected from near the hearth un-earthed in the 1930s, and the three samples of accumulated material collected from the tenth bed are 43.74%, 1.77%,3.88%,1.87% and 1.11%,respectively; those of the equivalent samples from the tenth bed outside the cave and samples from the fourth and seventh beds are at least one order of magnitude lower than the former抯. The above re-sults show that the sampling location of the tenth bed may be close to the hearth. Sampling over a wider range may lead to the finding of a location where the concentrations of EC are corresponding to the maximum values of EC in the hearth. The determination and study of EC may provide new evi-dence for the use of fire by Peking Man.
