[Vinegar processing attenuates toxicity on IEC-6 cells caused by chloroform extraction of Daphne genkwa].

To screen the toxic polar fractions of Daphne genkwa, compare the toxicity of D. genkwa on crypts epithelial cells IEC-6 before and after vinegar processing, and preliminarily investigate the mechanism of D. genkwa vinegar processing on toxicity reducing. The proliferation of IEC-6 cells was observed by MTT. The levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), lactate dehydrogenase (LDH), as well as the enzyme activity of Na⁺-K⁺-ATPase and Ca²âº-Mg²âº-ATPase were determined in IEC-6 cells to evaluate the oxidative damages degree of IEC-6 cells. The apoptosis and cell cycle were analyzed by Flow Cytometry. The results showed that the dichloromethane extraction was the toxic polar fraction of D. genkwa, and after vinegar processing, the toxicity of dichloromethane fraction was significantly reduced (P<0.01). As compared with the blank control group, the dichloromethane fraction of D. genkwa can obviously decrease the levels of SOD, Na⁺-K⁺-ATPase, Ca²âº-Mg²âº-ATPase (P<0.01) and content of GSH, but increase the level of LDH and MDA in cell supernatant (P<0.01). Besides, it obviously increased the early and late apoptotic rate of IEC-6 cells, obviously decreased the proportion of G1stage cells, increased the ratio of S stage cells and M stage cells (P<0.01). After vinegar processing, as compared with D. genkwa groups of various doses, it can significantly increase the levels of SOD, Na⁺-K⁺-ATPase, Ca²âº-Mg²âº-ATPase (P<0.01) and content of GSH, decrease the level of LDH, MDA(P<0.01), significantly decrease the early and late apoptosis rate of IEC-6 cells (P<0.01), increase the proportion of G1stage cells, and decrease the ratio of S stage cells and M stage cells (P<0.01). Vinegar processing can reduce the toxicity of dichloromethane fraction of D. genkwa, and its mechanism may be associated with improving the activity of antioxidant enzymes and permeability in IEC-6 cells, and decreasing the oxidative damage.

[Isolation and identification of arboviruses from mosquito pools in some regions of Liaoning province, China].

OBJECTIVE: To isolate and identify arboviruses from mosquito pools in some regions of Liaoning province. METHODS: Mosquitoes were collected from Shenyang, Yingkou, Panjin, Jinzhou and Dandong cities of Liaoning province in 2006. Viruses were isolated by inoculating the specimens onto C6/ 36 and BHK-21cells. The new isolates were identified using serological and molecular biological methods. RESULTS: 5410 mosquitoes were collected from the five cities in total. Three isolates produced CPE in C6/ 36 cell and five isolates produced CPE in both C6/36 and BHK-21 cell. Three isolates (LN0684, LN0688 and LN0689) were identified as Banna virus and one isolate (LN0636) was identified as Getah virus. Phylogenetic analysis showed that the three Banna virus strains were clustered into the same evolution branch as the other Chinese isolates. The identity of nucleotide sequence was between 91.2% and 94.7%, compared with other Banna virus strains. The new isolated Getah virus was clustered into the same branch with the strain of South Korea (swine). The identity of nucleotide sequence was 99.2%, when comparing with the strain of South Korea and was 95% to 99% with the strains from Russia, mainland of China and Taiwan region. Conclusion Eight virus isolates, including three Banna virus, one Getah virus and four unknown virus strains were isolated from mosquitoes in Liaoning province. Banna virus and Getah virus were reported for the first time in Liaoning province, while Getah virus showed the highest nucleotide homology with the South Korea strains.