目的:应用原子力显微镜(AFM)观察和分析体外循环(又称心肺分流术,CPB)30 min对红细胞膜表面的超微结构和生物力学性能的影响。方法:择期行体外循环心脏手术患者10例,分别取手术前和体外循环转机30 min的中心静脉血各2 m L,分为对照(CON...目的:应用原子力显微镜(AFM)观察和分析体外循环(又称心肺分流术,CPB)30 min对红细胞膜表面的超微结构和生物力学性能的影响。方法:择期行体外循环心脏手术患者10例,分别取手术前和体外循环转机30 min的中心静脉血各2 m L,分为对照(CON)组和CPB组,肝素抗凝。正立荧光显微镜观察计数2组非圆红细胞;AFM观察红细胞膜表面超微结构并进行力曲线测定。结果:与CON组比较,CPB组非圆红细胞比例差异无统计学意义;与CON组比较,CPB组细胞膜表面隆起呈紊乱排列,凹凸性增强,均匀度下降,膜表面颗粒分布有差异(P<0.05),平均粗糙度(Ra)和均方根粗糙度(Rq)增大(P<0.05),细胞膜黏附力升高(P<0.05),但膜形变恢复力和力曲线斜率差异无统计学意义。结论:体外循环转机30 min可以引起红细胞膜的表面形貌和超微结构改变,黏附性增大。展开更多
Objective: To evaluate the use of near-infrared spectroscopy for monitoring cerebral oxygenation under different cardiopulmonary bypass models. Method: Twenty-four patients with ventricular septal defect and pulmonary...Objective: To evaluate the use of near-infrared spectroscopy for monitoring cerebral oxygenation under different cardiopulmonary bypass models. Method: Twenty-four patients with ventricular septal defect and pulmonary hypertension undergoing open-heart surgery were assigned eight each to three groups, with respect to different cardiopulmonary bypass models: moderate hypothermia cardiopulmonary bypass, deep hypothermia low flow and deep hypothermia circulatory arrest. For each patient, cerebral oxygenation with near-infrared spectroscopy were monitored and the relative concentration changes in cerebral oxygenated hemoglobin, deoxygenated hemoglobin and oxidized cytochrome aa3 were calculated. Electroencephalography, biochemical indicators such as neuron-specific enolase and lactate, and performed correlation analyses for near-infrared spectroscopy data and biochemical indicators were also measured. Results: Near-infrared spectroscopy data and biochemical indicators for moderate hypothermia cardiopulmonary bypass and deep hypothermia low flow group showed no correlation. For deep hypothermia circulatory arrest group, oxygenated hemoglobin signal declined to a plateau （nadir） during the circulatory arrest period. The duration from reaching nadir until reperfusion “oxygenated hemoglobin signal nadir-time", and the minimum values of oxygenated hemoglobin, and oxidized cytochrome aa3 were closely correlated with increasing neuron-specific enolase and lactate. And, all patients whose oxygenated hemoglobin signal nadir-time was less than 35 min were free from behavioral evidence of brain injury. Conclusion: Near-infrared spectroscopy data including oxygenated hemoglobin signal nadir-time and the minimum of oxygenated hemoglobin and oxidized cytochrome aa3 showed strong correlation with other cerebral function assessment for deep hypothermia circulatory arrest. Oxygenated hemoglobin signal nadir-time determined by near-infrared spectroscopy can be useful in predicting the safe duration of circulatory arrest.展开更多
AIM： To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass （CPB） in rats. METHODS： Thirty anesthetized rats were randomly divided into two gr...AIM： To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass （CPB） in rats. METHODS： Thirty anesthetized rats were randomly divided into two groups： Group S （n = 10） served as sham operation and group C （n = 20） served as CPB which underwent CPB for 1 h. Expression of occludin and zonula occludens-1 （ZO-1） were determined by Western blotting and immunotochemistry, respectively. Plasma levels of diamine oxidase （DAO） and d-lactate were determined using an enzymatic spectrophotometry. RESULTS： Immunohistochemical localization of occludin and ZO-1 showed disruption of the tight junctions in enterocytes lining villi at the end of CPB and 2 h after CPB. The intensities of the occludin and ZO-i at the end of CPB were lower than those of control group （76.4% ± 22.5% vs 96.5% ± 28.5% and 62.4% ± 10.1% vs 85.5% ±25.6%, P 〈 0.05） and were further lower at 2 h after CPB （50.5% ± 10.5% and 45.3% ± 9.5%, P 〈 0.05）. Plasma d-lactate and DAO levels increased significantly （8.688 ± 0.704 vs 5.745 ± 0.364 and 0.898 ± 0.062 vs 0.562 ± 0.035, P 〈 0.05） at the end of CPB compared with control group and were significantly higher at 2 h after CPB than those at the end of CPB （9.377 ± 0.769 and 1.038 ± 0.252, P 〈 0.05）. There were significant negative correlations between occludin or ZO-1 expression and DAO （r^2 = 0.5629,r^2 = 0.5424, P 〈 0.05） or d-lactate levels （r^2 = 0.6512,r^2 = 0.7073, P 〈 0.05） both at the end of CPB and 2 h after CPB. CONCLUSION： CPB markedly down-regulates the expression of occludin and ZO-1 proteins in intestinal mucosa of rats. The close correlation between expression of tight junctions （TJs） and plasma levels of DAO or d-lactate supports the hypothesis that intestinal permeability increases during and after CPB because of decreases in the expressions of TJs.展开更多
文摘Objective: To evaluate the use of near-infrared spectroscopy for monitoring cerebral oxygenation under different cardiopulmonary bypass models. Method: Twenty-four patients with ventricular septal defect and pulmonary hypertension undergoing open-heart surgery were assigned eight each to three groups, with respect to different cardiopulmonary bypass models: moderate hypothermia cardiopulmonary bypass, deep hypothermia low flow and deep hypothermia circulatory arrest. For each patient, cerebral oxygenation with near-infrared spectroscopy were monitored and the relative concentration changes in cerebral oxygenated hemoglobin, deoxygenated hemoglobin and oxidized cytochrome aa3 were calculated. Electroencephalography, biochemical indicators such as neuron-specific enolase and lactate, and performed correlation analyses for near-infrared spectroscopy data and biochemical indicators were also measured. Results: Near-infrared spectroscopy data and biochemical indicators for moderate hypothermia cardiopulmonary bypass and deep hypothermia low flow group showed no correlation. For deep hypothermia circulatory arrest group, oxygenated hemoglobin signal declined to a plateau （nadir） during the circulatory arrest period. The duration from reaching nadir until reperfusion “oxygenated hemoglobin signal nadir-time", and the minimum values of oxygenated hemoglobin, and oxidized cytochrome aa3 were closely correlated with increasing neuron-specific enolase and lactate. And, all patients whose oxygenated hemoglobin signal nadir-time was less than 35 min were free from behavioral evidence of brain injury. Conclusion: Near-infrared spectroscopy data including oxygenated hemoglobin signal nadir-time and the minimum of oxygenated hemoglobin and oxidized cytochrome aa3 showed strong correlation with other cerebral function assessment for deep hypothermia circulatory arrest. Oxygenated hemoglobin signal nadir-time determined by near-infrared spectroscopy can be useful in predicting the safe duration of circulatory arrest.
文摘AIM： To investigate the tight junction protein expressions of intestinal mucosa in an experimental model of cardiopulmonary bypass （CPB） in rats. METHODS： Thirty anesthetized rats were randomly divided into two groups： Group S （n = 10） served as sham operation and group C （n = 20） served as CPB which underwent CPB for 1 h. Expression of occludin and zonula occludens-1 （ZO-1） were determined by Western blotting and immunotochemistry, respectively. Plasma levels of diamine oxidase （DAO） and d-lactate were determined using an enzymatic spectrophotometry. RESULTS： Immunohistochemical localization of occludin and ZO-1 showed disruption of the tight junctions in enterocytes lining villi at the end of CPB and 2 h after CPB. The intensities of the occludin and ZO-i at the end of CPB were lower than those of control group （76.4% ± 22.5% vs 96.5% ± 28.5% and 62.4% ± 10.1% vs 85.5% ±25.6%, P 〈 0.05） and were further lower at 2 h after CPB （50.5% ± 10.5% and 45.3% ± 9.5%, P 〈 0.05）. Plasma d-lactate and DAO levels increased significantly （8.688 ± 0.704 vs 5.745 ± 0.364 and 0.898 ± 0.062 vs 0.562 ± 0.035, P 〈 0.05） at the end of CPB compared with control group and were significantly higher at 2 h after CPB than those at the end of CPB （9.377 ± 0.769 and 1.038 ± 0.252, P 〈 0.05）. There were significant negative correlations between occludin or ZO-1 expression and DAO （r^2 = 0.5629,r^2 = 0.5424, P 〈 0.05） or d-lactate levels （r^2 = 0.6512,r^2 = 0.7073, P 〈 0.05） both at the end of CPB and 2 h after CPB. CONCLUSION： CPB markedly down-regulates the expression of occludin and ZO-1 proteins in intestinal mucosa of rats. The close correlation between expression of tight junctions （TJs） and plasma levels of DAO or d-lactate supports the hypothesis that intestinal permeability increases during and after CPB because of decreases in the expressions of TJs.
