AIM:To observe and analyze the effect of cardiopulmonary bypass ( CPB) for 30 min on surface ultra-structure and mechanical properties of the erythrocyte membrane by atomic force microscopy (AFM).METHODS:Ten cases of elective patients in cardiac surgery were selected in the study and divided into control ( CON) group and CPB group.The central venous blood (2 mL) before surgery and 30 min after CPB was collected with heparin anticoagulation . The non-circular red blood cells were counted under a stand fluorescence microscope .AFM was used to examine the ultra-structure of the membrane surface and measure the force curve of the erythrocytes .RESULTS:The percentage of non-cir-cular red blood cells in CPB group showed no statistically significant differences as compared with CON group .AFM images showed that the significant differences of membrane surface concave and convex , evenness , particle distribution , the sur-face average roughness (Ra), the surface root mean square roughness (Rq) and cell membrane adhesion between CPB group and CON group were observed .However, the membrane deformation resilience and curve slope had no significant difference between the 2 groups.CONCLUSION:Cardiopulmonary bypass for 30 min changes the morphology and ultra-structure of the erythrocyte membrane surface , and increases the adhesion between cells .

Objective To study the clinical effect of leflunomide combined with methotrexate in the treatment of skin lesions caused by psoriatic arthritis .Methods The clinical data of 90 patients with skin lesions caused by psoriatic arthritis were collected ,and they were divided into control group and observation group by simple random method,45 cases in each group.The control group was treated with methotrexate ,and the observation group was given leflunomide combined with methotrexate .Before treatment and after treatment for one month ,two months ,three months ,the skin lesions , psoriatic arthritis symptoms improvement , clinical effects and adverse reactions were observed in the two groups.Results After treatment for one month,two months,three months,the DLQL index scores in the observation group were (8.12 ±2.02)points,(6.55 ±1.47)points,(3.68 ±1.21)points,respectively,which were significantly better than those in the control group (t=2.54,3.92,4.44,P=0.01,0.01,0.01).After treatment for one month,two months,three months,the PASI index scores in the observation group were (7.57 ±3.22)points, (4.61 ±1.86)points,(3.11 ±2.17)points,respectively,which were better than those in the control group (t=3.42, 7.81,4.07,P =0.01,0.01,0.01).The total effective rate of the observation group was 88.89％,which was significantly higher than 68.89％of the control group (χ2 =5.40,P=0.02).No serious adverse reactions occurred in both two groups,and the difference was not statistically significant (11.11％ vs.13.33％,χ2 =0.10,P=0.75). Conclusion Compared with methotrexate alone , leflunomide combined with methotrexate in the treatment of skin lesions caused by psoriatic arthritis has obvious effect , and can significantly improve the symptoms of patients with skin and arthritis symptoms ,and it is more conducive to relieve patients'pain.

Objective To investigate the effect of long-term high-fat diet on cognitive function and hippocampus neurons ultrastructure in obese rats.Methods Forty SD rats were randomly assigned to a high fat diet (HFD) group and a common diet (CD) group.Meanwhile,HFD-induced obese rat model were established.The spatial learning and memory were measured by the Morris water maze,and the neurons ultrastructural changes in rat hippocampus CA1 region at the corresponding period were observed by transmission electron microscopy.Results The average weight of rats was 25％,28％,and 22％ higher in the HFD group than in the CD group at the 12,16,and 20 weeks,respectively;the Lee's indexes were 6％,4％,and 8％ higher;the average swimming latency were 52％,44％,and 40％ longer;the average swimming distance were 85％,45％,and 51％ longer;the average swimming speed were 57％,34％,and 18％ higher;the duration of staying in the target quadrant were 32％,54％,and 63％ shorter;and the average times of crossing the plate form were 30％,34％,and 34％ shorter,respectively (all P ＜0.001).In comparison of ultrastructure in hippocampus CA1 region of rats at corresponding time points,the amounts of degenerated and necrosis neurons,of the deformed and vacuolar mitochondria,and of the less rough endoplasmic reticulum were significantly more at 12,16,and 20 weeks in the HFD group than in the CD group.Conclusions Long-term HFD-induced obesity damages the structure of neurons in the hippocampus,impairs spatial learning and memory function,and accelerates cognitive aging in rats.