QCM-D技术在不同润湿性表面蛋白吸附研究中的应用

目的:利用石英晶体微平衡-分散(QCM-D)技术研究白蛋白在高度亲水和高度疏水表面的吸附情况.方法:利用等离子聚合技术在8片圆形石英传感器上形成六甲基二硅氧烷薄膜聚合体薄膜,将4片上述试样采用低温氧等离子体轰击80 s,这两种表面分别代表高度疏水及高度亲水表面.将处理后的两种传感器装人QCM-D检测仪,将400mg/L的牛血白蛋白溶液引入传感检测室,观察共振频率和离散因子随时间的变化,计算出蛋白的吸附量.结果:白蛋白在两种表面的吸附主要在早期10 s中完成,此后吸附变慢,在30 min左右达到吸附-离散平衡,30 min时白蛋白在高度疏水表面的平均吸附量为294.6 ng/cm2,而在高度亲水表面平均吸附量为235.1 g/cm2,两者有显著性差异.结论:QCM-D可以用来精确测定蛋白质在石英传感器表面的吸附,高度疏水性表面对白蛋白有较高的吸附能力.     

Effect of nicardipine versus enalapril on plasma endothelin-1 in hypertensive patients with type 2 diabetes mellitus

We compared the effects of dihydropyridine type Ca channel blocker slow-release nicardipine and angiotensin converting enzyme inhibitor enalapril on plasma endothelin-1 (ET-1) levels in hypertensive type 2 diabetic patients (n=20). Nicardipine or enalapril was administered for 6 months by a crossover design. Nicardipine and enalapril comparably lowered blood pressure. Enalapril significantly reduced urinary albumin excretion in microalbuminuric patients, whereas nicardipine did not. Urinary beta2-microglobulin excretion was significantly increased during nicardipine treatment. However, both drugs significantly reduced plasma ET-1 as compared with pretreatment levels, close to that in healthy control (2.9 +/- 0.3 pg/ml in control, 4.8 +/- 0.3 pg/ml before treatment, 3.2 +/- 0.3 pg/ml during nicardipine vs before treatment p<0.05, 2.9 +/- 0.4 pg/ml during enalapril vs before treatment p<0.01). The decrease in plasma ET-1 was significantly correlated with the increase in natriuresis in normoalbuminuric patients treated with enalapril ( r= -0.82, p<0.01) but not in those treated with nicardipine. Although nicardipine and enalapril had different renal effects, both drugs equally suppressed plasma ET-1 levels in hypertensive patients with type 2 diabetes.     

Resection of a mediastinal mature teratoma diagnosed owing to sudden chest pain with elevated preoperative serum CA19-9

Mediastinal teratomas are typically benign and asymptomatic, but they undergo sudden enlargement or rupture into neighboring organs in some patients owing to intratumoral hemorrhage, leading to serious complications. We report the case of a mediastinal mature teratoma that was discovered because of the sudden onset of chest pain accompanied by elevated preoperative serum CA19-9 levels. The patient was a 43-year-old man who experienced sudden chest pain and was brought to hospital in an ambulance. Chest radiography and computed tomography revealed a mediastinal tumor and a serum CA19-9 level that was elevated to 4377 U/ml. The tumor comprised soft tissue, fluid, and cystic components. The histological diagnosis was mature teratoma with peritumoral bleeding. Most epithelial components, including squamous epithelium and similar components in the bronchi, showed positive results for CA19-9 on immunohistological examination. The postoperative course was uneventful, and serum CA19-9 levels normalized.     

Small Cell Carcinoma of the Gallbladder Arising in a Patient with Pancreaticobiliary Maljunction without Bile Duct Dilatation

We report a 36–year-old female patient with small cell carcinoma of the gallbladder with liver metastasis, that was associated with pancreaticobiliary maljunction (PBM) without bile duct dilatation. On admission, a gallbladder mass and multiple liver tumors were detected by US, CT and ERCP. Moreover, ERCP clearly demonstrated an abnormally long common channel between the pancreatic and bile ducts, indicating PBMwithout choledochal dilatation. US-guided biopsy of the tumor histopathologically confirmed small cell carcinoma. The serum neuron-specific enolase (NSE) level was very high. Transarterial chemo-embolization followed by systemic chemotherapy resulted in marked tumor reduction, but this was followed by rapid exacerbation. The patient died of the tumor 145 days after admission. The proposed mechanism of the car-cinogenesis of this rare gallbladder malignancy under the preexisting condition of PBM was discussed. (Dig Endosc 1999, 11: 246–249)     

Aortic pressure augmentation as a marker of cardiovascular risk in obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is associated with increases in cardiovascular morbidity and mortality. Vascular changes in individuals with OSAS have not been fully elucidated, however. The possible impact of OSAS on the extent of aortic pressure augmentation (AG), an indicator of cardiovascular risk, was investigated. Forty-five consecutive male patients aged 35 to 78 years (56.0+/-9.6 years) who were referred to the sleep clinic of Nagoya University Hospital for screening and treatment of OSAS and 71 age-matched healthy men were enrolled in the study. AG was derived from the pressure waveform measured at the radial artery by applanation tonometry. The number of apnea and hypopnea episodes per hour (apnea-hypopnea index [AHI]) was determined by standard polysomnography. AG was significantly greater in OSAS patients than in controls (9.0+/-4.1 vs. 6.4+/-3.4 mmHg, p<0.001), and it was significantly reduced in 19 OSAS patients treated with continuous positive airway pressure. AG was also significantly correlated with the AHI (r=0.562, p<0.001) and age (r=0.356, p=0.016) but not with the serum concentrations of low and high density lipoprotein-cholesterol, triglyceride, or glycosylated hemoglobin. Stepwise multiple regression analysis revealed that the AHI was the most significant contributing factor to the increased AG in OSAS patients (beta=0.109, r=0.530, p<0.001). OSAS may thus have an adverse effect on vascular function that can be ameliorated by appropriate treatment.     

The effect of surfactant therapy associated with high frequency jet ventilation on oxygenation in canine lavaged lungs

The effects of exogenous surfactant (SF) replacement therapy associated with high frequency jet ventilation (HFJV) on blood gas changes, pulmonary and hemodynamic variables were studied in canine lavaged lungs. The lungs were lavaged repeatedly with physiological saline until PaO2 decreased to 100 mmHg under intravenous pentobarbital anesthesia with 100% oxygen. SF (50 mg.kg-1) in the experimental group (n = 12) and saline in the control group (n = 8) were administered to the trachea using HFJV with a duration of 10 min. HFJV was further continued for 1 hour to make surfactant distribute evenly. Then respiration was controlled by the conventional mechanical ventilator for 3 hrs. During the administration of SF (10 min). PaCO2 was not altered. In the surfactant group, PaO2 improved significantly (200 mmHg) at the end of HFJV and was maintained for the next 3 hrs at this level, but it did not improve in the saline group. Therefore, we suggest that HFJV can be used safely for the treatment of acute respiratory failure and is an effective method for the administration of the pulmonary surfactant into the alveoli.     

Effect of forphenicinol on the production of Ia-positive macrophages in mice with or without L1210 leukemia and on the growth of L1210 in immunized mice

Oral administration of forphenicinol, S-2-(3-hydroxy-4-hydroxymethylphenyl)glycine, increased the production of Ia-positive peritoneal macrophages in healthy mice. Moreover, forphenicinol increased Ia-positive macrophages in L1210-bearing mice. Though forphenicinol was ineffective against mouse leukemia L1210 when administered alone, in combination with L1210 vaccine it prolonged the survival time of L1210-bearing mice and the increase in the number of Ia-positive macrophages in peritoneal cavity coincided with the prolongation of the survival time. These results suggest that the initial action of forphenicinol is the preferential induction of Ia-positive macrophages, which play a role in the subsequent activation of various immune responses including macrophage activation.