Objective To investigate the inhibitory effect of cryptotanshinone on different maturation stages of Staphylococcus epidermidis (S.epidermidis) biofilm.Methods The biofilm model of S.epidermidis was constructed in vitro, the timing of adhesion, accumulating, and maturation was determined;matrix quantity, bacterial metabolism, microstructure of biofilm were detected with semi-quantitative adhesion test, XTT assay, and scanning electron microscope(SEM) respectively.Results The timing of adhesion, accumulating, and maturation of S.epidermidis biofilm were 6h, 24h,and 48h respectively;in adhesion period, cryptotanshinone at the concentration of 128μg/mL and 32μg/mL could both obviously reduce the matrix and kill bacteria inside biofilm, difference was statistically significant(P<0.05),inhibitory effect of 128μg/mL cryptotanshinone was better than 32μg/mL (P<0.05), the microstructure was destroyed by both concentrations.During accumulating and mature period, only cryptotanshinone at 128μg/mL could reduce the matrix of biofilm and kill bacteria inside biofilm (P<0.05), the microstructure was damaged by cryptotanshinone at concentration of 128μg/mL, while 32g/mL of cryptotanshinone had no obvious inhibitory effect(P>0.05).Conclusion Cryptotanshinone has a certain inhibitory effect on different stages of S.epidermidis biofilm, and there is a certain dose effect.

Objective To understand the distribution and drug resistance of pathogens causing catheter related bloodstream in‐fection (CRBSI) to provide reference for clinical treatment .Methods The distribution and drug resistance of pathogens isolated from the central venous catheter from January 2011 to June 2015 were retrospectively analyzed .Results Among 731 submitted samples ,38 cases were CRBSI ,with the positive rate of 5 .3% ,in which ,the Gram‐positive cocci accouted for 26 .3% of isolated bacteria and dominated by Staphylococcus epidermidis (13 .2% ) ,moreover which was MRSE .MRSA and VRE were not detected . Gram‐negative bacilli accounted for 73 .7% of isolated bacteria and dominated by Acinetobacter baumannii (42 .1% ) ,which was most sensitive to amikacin with the sensitivity rate of 87 .5% .Conclusion Acinetobacter baumannii is most common pathogen in CRBSI with serious drug resistance ,therefore the operating should be standardized in clinical work for controlling infection .