Objective: To investigate the action of low level soybean isoflavones (genistin, genistein and daidzein) on the oxidative modification of lipoproteins in serum. Methods: After a system of lipoprotein oxidation mediated by Cu 2+ was established in a dilute serum, the effects of soybean isoflavones on the course and the end of lipoprotein oxidation could be reflected by monitoring the production of conjugated dienes and thiobarbituric acid-reactive substances (TBARS) respectively when isoflavones were added. Results: After 0.5-10 ?mol/L genistein, daidzein, genistin or ?-tocopherol was added into the lipoprotein system respectively before the oxidation initiated by Cu 2+ , the production of conjugated dienes or TBARS in the system was significantly reduced with a dose-dependent relationship. When the lipoprotein oxidation was initiated by Cu 2+ at 37 ℃ for 1 h or 1.5 h, soybean isoflavones also revealed strong inhibition on the oxidation in a weakening way. In comparison with soy isoflavones, ?-tocopherol had smaller inhibition on the production of conjugated dienes, but had promotion on the increase of TBARS. Conclusion: Lipoprotein oxidative modification in serum was weakened by low level soybean isoflavones, and its action after the oxidation initiated was more effective than that of ?-tocopherol.

Objective To observe the effect and safety of low dose milrinone used in patients suffering from refractory heart failure and renal dysfunction. Methods Forty-two patients with refractory heart failure and renal dysfunction were divided into treatment group(21 cases ) and control group(21 cases )by random digits table. All the patients accepted a therapy of cardiac booster, diuretics and vasodilators, and treatment group also accepted the therapy of milrinone [0.375 μ g/( kg· min), 10 mg/d, for 7 days]. And then the symptom, signs, blood pressure, heart rate, heart function and renal function before and after the treatment were observed. Results The total effective rate in treatment group was 85.7%( 18/21 ) ,significantly higher than that in control group [57.1% (12/21)] (P ＜0.05＝. After treatment,the heart rate,systolic blood pressure,diastolic blood pressure,stroke volume,cardiac output and left ventricular ejection fraction in treatment group and control group improved significantly than those before treatment, and these index improved better in treatment group [(79.3 ± 12.4) beats/min vs. (85.4 ± 10.2) beats/min, ( 107.6 ± 15.4)mm Hg ( 1 mm Hg = 0.133 kPa) vs.( 119.1 ± 13.5 ) mm Hg, (60.8 ± 9.4) mm Hg vs. (65.8 ± 8.5 ) mm Hg,(66.3 ± 10.2 ) ml vs. (61.2 ± 9.3 ) ml, (5.3 ± 0.6 ) L/min vs. (4.8 ± 0.9) L/min, (56.6 ± 8.4 )% vs. (48.9 ±7.3)% ,P ＜ 0.05＝. In two groups,there were no statistical difference in renal function. Conclusions Low dose of milrinone can improve the heart function of the patients with refractory heart failure and renal dysfunction and has good renal safety.

Objective To establish a stable and reliable model of brain death in swine, and to provide a more stable model for investigating pathomorphology in brain tissue and for studying transplantation immunology during brain death. Methods Base on the classic methodology of increasing epidural intracranial pressure, Codman intracranial pressure moni-toring probes were implanted in landrace pigs invasively. According to the relationship between ICP and MAP, brain death models were established by increasing intracranial pressure slowly and intermittently, with real-time monitoring of the intra-cranial pressure. Results Among twelve experimental landrace pigs, one died from anesthetic accident, while the rest elev-en were successfully established as brain death models. With effective respiratory and circulatory support, those brain death models can be maintained for (31.3 ± 4.7) h. Brain death model establishement is a stable and reliable process demonstrated by transcranial Doppler, EEG, ECG, mean arterial blood pressure and other monitoring methods. After brain death is con-firmed, animal models can be maintained for a long time. Conclusion Our methodology of inducing brain death model un-der ICP monitoring is stable and easy to be standardized. It can also provide a more stable model for studying brain tissue pathomorphology and transplantation immunology.

Objective To reproduce a stable animal model of brain death in pigs, observe the change regularity of cerebral oxygen metabolism during the process of brain death, and to evaluate the significance and value of cerebral oxygen metabolism parameters for the diagnosis of brain death. Methods Twelve landrace pigs were used to create the brain death models using modified method of increasing epidural intracranial pressure (ICP). The mean arterial pressure (MAP) and ICP were monitored continuously during the process. The pigs were divided into four groups according to cerebral perfusion pressure (CPP) decreasing degree during brain death, namely CPP normal group and CPP decreasing 0%-30%, 30%-70%, and 70%-100% groups. Blood gas analysis of the external carotid artery and internal jugular vein were monitored discontinuously. The changes in cerebral oxygen metabolism parameters, including external carotid artery-internal jugular vein bulb oxygen content difference (AJDO2), internal jugular bulb-external carotid artery carbon dioxide partial pressure difference (DPCO2) and DPCO2/AJDO2 ratio, were observed. Results Brain death model were successfully reproduced in 12 experimental pigs. With MAP and ICP monitoring, the models at different stages of CPP could be repeatedly induced. The levels of AJDO2 and DPCO2 were increased gradually and then decreased, while the ratio of DPCO2/AJDO2 was constantly increased with the decrease of CPP. The level of AJDO2 in CPP decreasing 0%-30%group was significantly higher than that in CPP normal group [(5.86±1.21)% vs. (3.92±0.64)%], the levels of DPCO2 in CPP decreasing 0%-30% and CPP decreasing 30%-70% groups were significantly higher than those in CPP normal group [mmHg (1 mmHg = 0.133 kPa): 10.33±1.83, 11.48±2.32 vs. 6.11±1.43], and the ratios of DPCO2/AJDO2 in CPP decreasing 30%-70% and CPP decreasing 70%-100% groups were significantly higher than those in CPP normal group and CPP decreasing 0%-30% group (2.81±0.53, 4.12±1.07 vs. 1.57±0.64, 1.62±0.81). All the differences above were statistically significant (all P < 0.05). Conclusions With the decrease of CPP, cerebral oxygen metabolism showed a regular change during brain death. DPCO2 combined with DPCO2/AJDO2 is a reliable blood gas analysis index indicating intracranial hypoperfusion, which has certain reference value for the determination of brain death.