Complementary use of fluorescence and magnetic resonance imaging of metastatic esophageal cancer in a novel orthotopic mouse model.

We describe the development of an aggressive orthotopic metastatic model of esophageal cancer, which is visualized in real time with combined magnetic resonance imaging (MRI) and fluorescence imaging. The aim of the study was to describe the development of a novel model of metastatic tumor disease of esophageal carcinoma and use this model to evaluate fluorescence and MRI in early detection of local and metastatic disease. The human esophageal adenocarcinoma cell line PT1590 was stably transfected with green fluorescent protein (GFP). Nude mice were orthotopically implanted with PT1590-GFP cells. Orthotopic tumor growth as well as metastatic spread was examined by fluorescence imaging and high-resolution MRI at defined intervals after orthotopic implantation. Highly aggressive novel fluorescent cell lines were isolated from metastatic tissues and put into culture. After implantation of these cells, 100% of the animals developed orthotopic primary tumors. In 83% of animals, metastatic spread to liver, lung and lymph nodes was observed. Primary tumor growth could be visualized with fluorescence imaging and with MRI with high correlation between the 2 methods. Fluorescence imaging allows fast, sensitive, and economical imaging of the primary and metastatic tumor without anesthesia. With MRI, anatomical structures are visualized more precisely and tumors can be more accurately localized to specific organs. This model should prove highly useful to understand esophageal carcinoma and to identify novel therapeutics for this treatment-resistant disease.

Alveolar recruitment strategy and high positive end-expiratory pressure levels do not affect hemodynamics in morbidly obese intravascular volume-loaded patients.

We evaluated the effect of the alveolar recruitment strategy and high positive end-expiratory pressure (PEEP) on hemodynamics in 20 morbidly obese (body mass index 50 +/- 9 kg/m2), intravascular volume-loaded patients undergoing laparoscopic surgery. The alveolar recruitment strategy was sequentially performed with and without capnoperitoneum and consisted of an upward PEEP trial, recruitment with 50-60 cm H2O of plateau pressure for 10 breaths, and a downward PEEP trial. Recruitment and high PEEP did not cause significant disturbances in any hemodynamic variable measured by systemic and pulmonary artery catheters. Transesophageal echocardiography revealed no differences in end-diastolic areas or evidence of segmental abnormalities in wall motion.

The role of vascular adhesion molecules PECAM-1 (CD 31), VCAM-1 (CD 106), E-selectin (CD62E) and P-selectin (CD62P) in severe porcine pancreatitis.

Inflammatory cytokines have been shown to mediate organ damage by their action on vascular endothelia and leukocytes, in part by upregulating the expression of adhesion molecules, which in turn convey transmigration of leukocytes into tissue. The upregulation and activation of vascular cell adhesion molecules on the endothelial cells avail firm leukocyte adhesion to the vascular endothelium and enhance their transmigration and consecutive tissue injury. The aim of this study was to evaluate the expression of vascular adhesion molecules CD 31 (PECAM-1), CD 106 (VCAM-1), CD 62E (E-Selectin) and CD 62P (P-Selectin) in the pancreas and distant organs of pigs suffering from acute necrotizing pancreatitis (AP). AP was induced in 13 pigs by a combination of intravenous cerulein and intraductal glycodeoxycholic acid. For immunostaining of vascular adhesion molecules slides of porcine pancreas, lung, kidney and liver tissue were stained with monoclonal antibodies (Ab) against PECAM-1-1, VCAM-1 E- and P- SELECTIN. The endothelial cell expression of CD 31 (PECAM-1), CD 106 (VCAM), CD 62E (E-Selectin) and CD 62P (P-SELECTIN) in severe porcine pancreatitis is detectable and upregulation is partly significantly.