Objective To explore and evaluate the efficiency of the leucocyte depletion filter on eliminating tumor cells from blood, and its influence on the morphology and function of red blood cells. Methods Blood from operation field was collected, filtered, centrifuged and washed. Intestinal cancer cells (LOVO) and gastric cancer cells (SGC) were cultured in vitro and mixed with the collected blood. Blood contaminated with known number of tumor cells was then centrifuged and washed with cell retriever, and then the mixture was filtered with leucocyte depletion filter. The amount of residual tumor cells in filtered blood was counted after trypan blue staining before and after culturing. Unwashed and unfiltered blood containing tumor cells were used as control and were also cultured. The morphology and Na+-K+-ATPase activity of treated red blood cells was assessed. Results Tumor cells were detectable after only being washed with cell retriever and grew well after culturing for two weeks. No tumor cells were found after both washed with cell retriever and filtered with leucocyte depletion filter, and no tumor cell grew two weeks after culturing. No change was found in morphology and Na+-K+-ATPase activity of red blood cells after being washed and filtered. Conclusion Cell retriever is not able to eliminate tumor cells from blood completely. Further filtration with leucocyte depletion filter is capable of completely eliminating the residual tumor cells in blood. The morphology and Na+-K+-ATPase of red blood cells do not change after being washed with cell retriever and being filtered with leucocyte depletion filter.

Objective To investigate the effect of isolated carotid sinus perfusion with propofol on plasma endothelin and nitric oxide levels in diabetic rats.Methods Healthy adult Wistar rats weighing 180-220 g were used in this study.Diabetes mellitus was induced by intraperitoneal streptozotocin 30 mg/kg and confirmed by blood glucose ≥ 16.7 mmol/L.Thirty-six rats in which diabetes mellitus model was successfully established were randomly divided into 3 groups ( n =12):control group (group DC) ;low dose propofol group (group DP1 ) and high dose propofol group (group DP2 ).Another 36 non-diabetic rats were also randomly divided into 3 group ( n =12 each):control group (group NC) ; low dose propofol group group (group NP1 ) and high dose propofol (group NP2 ).After 30 min isolated carotic sinus perfusion with K-H solution (control groups),50 μmol/L propofol in K-H solution (low dose propofol groups) or 100 μmol/L propofol in K-H solution (high dose propofol groups),blood samples were taken for determination of plasma endothelin and nitric oxide concentrations.Results The plasma endothelin concentration was lower and nitric oxide concentration higher in groups DP1 and DP2 than in group DC,and in group DP1 than in group DP2 ( P ＜ 0.05).The plasma endothelin concentration was higher and nitric oxide concentration lower in group NPi than in group DP1,and in group NP2 than in group DP2 ( P ＜ 0.05 ).Conclusion Propofol can decrease endothelin level and increase nitric oxide level in diabetic or non-diabetic rats through local effect on carotid sinus,and the effect is stronger in diabetic rats than in non-diabetic rats.

Objective To investigate the effects of sevoflurane pretreatment on the myocardial injury in patients undergoing cardiac valve replacement with cardiopulmonary bypass (CPB).Methods Twenty NYHA class Ⅱ or Ⅲ patients,aged ＜ 60 yr,undergoing cardiac valve replacement with CPB,were randomly divided into 2 groups (n =10 each):sevoflurane group (group S) and control group (group C).The patients were premeditated with intramuscular morphine and scopolamine.Anesthesia was induced with iv injection of midazolam 0.05-0.08 mg/kg,fentanyl 10-15 μg/kg and pipecuronium 0.08-0.10 mg/kg.Anesthesia was maintained with intermittent iv boluses of midazolam,fentanyl and pipecuronium and in addition sevoflurane was inhaled before aortic clamping and the end-tidal concentration was rapidly increased to 1.0％ and maintained at the level for 5 min in group S.Blood samples were taken from the central vein before skin incision (T1),immediately after aortic clamping (T2 ),at 0 and 30 min after aortic unclamping (T3-4),and at 2,6,12 and 24 h after operation (T5-8) for determination of the concentration of serum cardiac troponin Ⅰ (cTnI) and activities of creatine kinase (CK) and creatine kinase isoenzyme-MB (CK-MB).Myocardial specimens were taken from right auricle before aortic clamping and at 10 min after aortic unclamping for electron microscopic examination.Results The concentration of serum cTnI and activities of CK and CK-MB were significantly increased at T4-8 in both groups ( P ＜ 0.05).The serum cTnI concentration at T4-8 and the activities of CK and CK-MB at T8 were significantly lower in group S than in group C ( P ＜0.05).Different degrees of mitochondrial swelling were observed after aortic unclamping in both groups,but the changes were milder in group S than in group C.Conclusion Sevoflurane pretreatment can attenuate the myocardial injury in patients undergoing cardiac valve replacement with CPB.