The process of production of lactide from butyl lactate was investigated. The process consists of two stages： oligomerisation of butyl lactatean and depolymerisation of oligomers. The type catalysts of the series of ...The process of production of lactide from butyl lactate was investigated. The process consists of two stages： oligomerisation of butyl lactatean and depolymerisation of oligomers. The type catalysts of the series of Lewis acid were tested. It was found that SnCI4 is the most efficient catalyst for both stages.展开更多
Objective:To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide(G4PAMAM/VEGFASODN) compound on the expressions of vascular endothelial growth factor(...Objective:To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide(G4PAMAM/VEGFASODN) compound on the expressions of vascular endothelial growth factor(VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods:We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability,in vitro transfection efficiency and toxicity,and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results:The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10,it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%,significantly higher than that of the liposome group(P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion:With a low toxicity,high safety,and high transfection rate,G4PAMAM/VEGFASODN could be a promising gene vector. Specifically,it inhibits VEGF gene expression efficiently,laying a basis for further in vivo animal studies.展开更多
文摘The process of production of lactide from butyl lactate was investigated. The process consists of two stages： oligomerisation of butyl lactatean and depolymerisation of oligomers. The type catalysts of the series of Lewis acid were tested. It was found that SnCI4 is the most efficient catalyst for both stages.
基金Project (No. 30572140) supported by the National Natural Science Foundation of China
文摘Objective:To study the effects of the generation 4 polyamidoamine/vascular endothelial growth factor antisense oligodeoxynucleotide(G4PAMAM/VEGFASODN) compound on the expressions of vascular endothelial growth factor(VEGF) and its mRNA of breast cancer cells and on the inhibition of vascular endothelial cells. Methods:We examined the morphology of G4PAMAM/VEGFASODN compound and its pH stability,in vitro transfection efficiency and toxicity,and the expressions of VEGF and its mRNA. Methyl thiazolyl tetrazolium assay was used to detect the inhibitory function of the compound on vascular endothelial cells. Results:The compound was about 10 nm in diameter and was homogeneously netlike. From pH 5 to 10,it showed quite a buffered ability. The 48-h transfection rate in the charge ratio of 1:40 was 98.76%,significantly higher than that of the liposome group(P<0.05). None of the transfection products showed obvious toxicity on the cells. The expressions of both VEGF protein and its mRNA after G4PAMAM/VEGFASODN transfection decreased markedly. Conclusion:With a low toxicity,high safety,and high transfection rate,G4PAMAM/VEGFASODN could be a promising gene vector. Specifically,it inhibits VEGF gene expression efficiently,laying a basis for further in vivo animal studies.
