In order to study the relationship between Staphylococcal nuclease(SNase) and diabetes mellitus,genetic engineering bacteria E.coli BL21/pET28a-His-SNase was constructed,the expression of soluble extracellular protein SNase was induced and the a preliminary research was made on it.An expression vector pET28a-His-SNase plasmid containing the His-SNase gene was constructed and transformed into E.coli BL21 (DE3) competent cells.The protein was induced by lactose and purified by ultrasound destruction and Ni-affinity chromatography,respectively.It was then analyzed by SDS-PAGE and Western blot.The enzymatic properties for SNase has been preliminary studied as well.Results indicated that the purity of the correctly expressed fusion protein HisSNase was over 85％.SNase showed good activity within a wide range of pH and good heat resistance.This experiment might be a foundation work for the further study on the relationship between SNase and with diabetes.

Objective To investigate the relationship of alcohol exposure during pregnancy and non-compaction cardiomyopathy (NCC) in offspring mice.Methods Pregnant mice of ED3.5-ED18.5 were given 56％ alcohol by gavage at a dose of 5 mL/kg.The ED19.5 mice were sacrificed,and the heart of the fetal mice was harvested.Transmission electron microscopy (filaments,mitochondria and sarcoplasmic reticulum) and HE staining were used to verify the changes of structure and ultrastructure of the obtained myocardial tissues.Echocardiography was used to evaluate the cardiac function and ventricular myometrium of the offspring mice after growing up.Results Alcohol exposure during pregnancy caused the disorganized and dissolved myofilaments in the fetal mice.Some offspring mice (31.25％,5/16) had NCC.The ratio of non-compacted myocardium to compact myocardium at the end of systole (N/C) was 2.49 ± 0.6 in the offspring mice of the alcohol exposure group,significantly higher than that in the control offspring mice (0.62 ± 0.23,t =10.397,P =0.000).The volume of heart was decreased in the offspring mice of the alcohol exposure group while the left ventricule was enlarged.Echocardiography showed cardiac dysfunction and thickened ventricular septal/left ventricular posterior walls in the grown-up mice of the exposure group.Conclusion Large dose of alcohol exposure during pregnancy cause trabeculations and non-compaction in ventricular myocardium,and it might be one of causers for NCC in the offspring.