Baicalein (BAI) is an effective bactericide. The antibacterial activity and mechanism experiments were carried out by determining conductivity and content of macromolecules of membrane penetrability, the oxidative respiratory metabolism and protein synthesis changes and the inhibition of DNA topoisomerase activities. Electrical conductivity and the number of large molecules of BAI increased 2.48% and 1.8%, respectively, than that of the control. However, the membrane integrity did not destroyed by BAI directly. With BAI treatment, inhibition rates of activities for SDH and MDH were 56.2% and 57.4%, respectively, demonstrating that BAI could inhibit cell respiratory. After treated with BAI for 20 h, the total soluble content of proteins decreased by 42.83%. Moreover, the activities of DNA topoisomerase I and II were inhibited completely by 0.2 mmol x L(-1) BAI. These results indicated that BAI had obvious antibacterial activity on Staphylococcus aureus. The mechanism is that it could affect bacterial membrane penetrability, inhibit protein synthesis and influence SDH, MDH and DNA topoisomerase I and II activities to exert its antibacterial functions.

objective To investigate the ability of insulin sensitivity index HOMA2-%S and secretion function index HOMA2-%B calculated by HOMA2,the new homeostasis model assessment,in clinical application. Methods Eighty female volunteers with polycystic ovary syndrome in Chongqing area [50 subjects with normal glucose tolerance(NGT group)and 30 subjects with impaired glucose regulation(IGR group)]were involved in this study.Thev underwent a 75 g oral glucose tolerance test(OGTF)and the Botnia clamp test. From the data of faming blood samples in OGTF,insulin sensitivity index HOMAI-ISI,secretion function index HOMAl-β and disposal index DI-HOMA1 were calculated by the old homeostasis model assessment(HOMA I),meanwhile insulin sensitivity index HOMA2-%S,secretion function index HOMA2-%B and disposal index(DI-HOMA2) were caleulated by the new homeostasis model assessment (HOMA2).Correlation coefficients between insulin sensitivity index and GIR (the glucose infusion rate at steady state of Botnia clamp test),and between insulin secretion function index and AIR(the acute insulin response in Botnia clamp test),were studied.Results The Pearson's linear correlation coefficient between HOMA2-%S and GIR(r=0.503),HOMA1-ISI and HOMA2-%S (r= 0.990).HOMA2-%B and AIR(r=0.382),HOMA1-B and HOMA2-%B(r=0.976) were all statistically significant(a11 P<0.01).The glucose disposal indexes calculated from the HOMA2 and HOMA1 of 1GR group were significantly lower than those from the NGT group(t=2.825,P<0.Ol;t=2.222,P<0.05). Conclusion The HOMA2 is a better model in evaluating the insulin sensitivity and secretion function and is recommended to be widely used in clinical evaluation.

Sixty-six volunteers,including 24 subjects with normal glucose tolerance(NGT),18 patients with impaired glucose regulation (IGR),and 24 patients with type 2 diabetes mellitus ( T2DM ),underwent a test of continuous glucose monitoring.The data of continuous glucose monitoring were embedded into two-dimension Euclid space by Takens' embedding theory.Glycemic phase diagram was drawn by MATLAB.The area and center distance of glycemic phase diagram were calculated by computer.The distinction of glycemic variability and average glycemic level among different glucose regulation populations were analyzed.The results showed that there existed significant differences in body mass index,systolic blood pressure,diastolic blood pressure,low density lipoprotein-cholesterol,high density lipoprotein-cholesterol,triglyceride,total cholesterol,creatinine,and alanine aminotransferase among three groups( all P＜0.05 ).The levels of HbAIC,fasting plasma glucose( FPG ),postprandial 2 h plasma glucse (2hPG),area and center distance of glycemic phase diagram in T2DM group were higher than those in NGT and IGR groups( P＜0.01 ),and the levels of FPG,2hPG,area and center distance of glycemic phase diagram in IGR group were higher than those in NGT group( P＜0.01 ).The levels of FPG and 2hPG were correlated with area and center distance of glycemic phase diagram ( all P＜0.01 ).These results suggest that measuring the area and center distance of glycemic phase diagram is a good method to assess glycemic variability and average glycemic level during continuous glucose monitoring.