Objective To observe the bacteriostatic effect of chitosan lactate with different relative molecular masses in vitro. Methods The MICs of the chitosans lactate with different relative molecular masses against the usual pathogens were detected,and the MBCS against two standard strains were also determined. Levofloxacin hydrochloride was used as a control drug. Results The MIC90 of chitosan lactate with 10,30,50kDa against 50 strains of gram-positive cocci and 50 strains of gram-negative bacilli were 0.5,1~4,0.5~4mg?mL-1 and 1~4,0.5~1 ,0.5~4mg?mL-1,respectively. The MIC90 of levofloxacin hydrochloride against the 50 strains of gram-positive cocci and 50 strains of gram-negative bacilli were 4～8 and 8～16?g?mL-1,respectively. ATCC 25923 strain of S.aureus and ATCC 25922 strain of E.coli could be killed by 10kDa chitosan lactate in the concentration of 4mg?mL-1. The MBCS of levofloxacin hydrochloride against ATCC25923 strain of S.aureus and ATCC 25922 strain of E.coli were 2 and 4?g?mL-1,respectively. Conclusion The 4 species of the experimental bacteria could be inhibited by the chitosan lactate with 10,30 and 50kDa Mr in vitro,but the inhibitory effect of the chitosan lactate with 10kDa Mr was stronger among them. ATCC 25923 strain of S.aureus and ATCC25923 strain of E.coli could be killed only by 10kDa chitosan lactate in vitro,not by others.

Objective To evaluate effect of intensive insulin treatment(IIT)on healthcare-associated infection (HAI)rate in patients with acute stroke and stress hyperglycemia.Methods Databases,including PubMed,Em-base,Cochrane Library,WanFang,and China National Knowledge Infrastructure(CNKI)Data,were electronically searched,relevant journals and references of the included literatures were also searched manually,literatures were selected according to the uniform inclusion and exclusion criteria,incidence of HAI and mean blood glucose in patients who received IIT for acute stroke were assessed systematically.Results A total of 13 randomized controlled trials (RCT)involving 1 032 patients were included in this systematic review.Meta-analysis results showed that 10 studies involving 832 patients were finally enrolled for comparing HAI rate, HAI rates in IIT group and conventional insulin treatment group were 28.3% and 56.1 %,respectively(Z =4.50 ),difference between two groups was statistically significant (RR=0.53 [95 %CI :0.40 to 0.70],P <0.001 );A total of 328 patients in 5 studies were finally included in the comparison of blood glucose,difference in mean blood glucose between two groups was statistically significant(MD =-2.52 [95% CI :-4.30 to -0.74],P =0.006).Funnel plot of HAI rate revealed that there was publication bias.Conclusion IIT is used for the regulation of stress hyperglycemia in acute stroke,it can reduce the incidence of HAI and blood glucose in patients.