P物质及其受体在胰腺癌细胞中的表达

目的 了解P物质(SP)、神经激肽-1受体(NK-1R)及中性肽链内切酶(NEP)在胰腺癌细胞中表达。方法应用实时定量逆转录-聚合酶链反应(RQ-RT-PCR)技术,检测正常胰腺、胰腺癌组织和7株胰腺癌细胞中前速激肽原A(PPT-A)、NK-1R和NEP的mRNA表达,应用Westernblot检测NK-1R和NEP的蛋白水平。结果正常胰腺组织PPT-A的mRNA表达水平为0.430 0±0.464 7,胰腺癌组织中为1.790 0±1.833 1(P<0.05);正常胰腺NK-1R的mRNA表达水平为0.088 2±0.086 8,胰腺癌组织中为2.154 5±2.103 1(P<0.01);正常胰腺组织NEP的mRNA表达水平为3.234 7±6.301 0,胰腺癌为8.606 9±8.703 2(P>0.05)。Western Blot结果发现,胰腺癌组织中NK-1R蛋白也过度表达,而NEP的蛋白水平未相应上调。结论 胰腺癌组织中SP和NK-1R都明显上调,而SP的降解酶——NEP未相应上调,这表明胰腺癌组织中SP的产生与灭活的平衡被打破,产生过多的SP,发挥过度的生物学效应。     

胰腺癌细胞株对氟尿嘧啶存在固有不敏感性

目的 研究胰腺癌细胞株是否对氟尿嘧啶（5-FU）具有固有或获得性不敏感。方法 用SRB方法检测5-FU对胰腺癌细胞株AsPC-1,Capan-1,Mia-PaCa-2,Panc-1和T3M4的毒性作用。结果 5-FU对所有胰腺癌细胞株的IC50都很高，其中Mia-PaCa-2和Panc-1细胞株对5-FU最不敏感（IC50=12，13nmol/L)。即使是在5-F鄣敏感的Capan-1细胞株，其IC50仍相当高（473pmol/L)。这些细胞株对5-FU的IC50甚至高出其临床常用剂量给药时血浆药物浓度的1-56倍。结论 大多数胰腺癌细胞株对5-FU固有不敏感，这些发现也许能作为临床上5-FU对胰腺癌疗效差的解释之一。     

AIRFIX: the first digital postoperative chest tube airflowmetry—a novel method to quantify air leakage after lung resection

Objective: Prolonged air leak after pulmonary resection is a common complication and a major limiting factor for early discharge from hospital. Currently there is little consensus on its management. The aim of this study was to develop and evaluate a measuring device which allows a simple digital bed-side quantification of air-leaks compatible to standard thoracic drainage systems. Patients and methods: The measuring device (AIRFIX^®) is based upon a ‘mass airflow’ sensor with a specially designed software package that is connected to a thoracic suction drainage system. Its efficacy in detecting pulmonary air-leaks was evaluated in a series of 204 patients; all postoperative measurements were done under standardized conditions; the patients were asked to cough, to take a deep breath, to breathe out against the resistance of a flutter valve, to keep breath and to breathe normally. As standard parameters, the leakage per breath or cough (ml/b) as well as the leakage per minute (ml/min) were displayed and recorded on the computer. Results: Air-leaks within a range of 0.25–45 ml/b and 5–900 ml/min were found. Removal of the chest tubes was done when leakage volume on Heimlich valve was less than 1.0 ml/b or 20 ml/min. After drain removal based upon the data from chest tube airflowmetry none of the patients needed re-drainage due to pneumothorax. Conclusion: The AIRFIX^® device for bed-side quantification of air-leaks has proved to be very simple and helpful in diagnosis and management of air-leaks after lung surgery, permitting drain removal without tentative clamping.