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The most frequent and most dangerous complication of the duodenopancreatectomy is pancreatic fistula due to dehiscence of the pancreatic anastomosis. A technique that uses a separate Roux en Y loop for pancreatic anastomosis, to reduce the fatal risks of the pancreatic fistula, has been initially reported more than 50 years ago. With the development of the pancreaticogastrostomy, it seems interesting to present a procedure using an isolated loop for the pancreas; this technique is derived from those previously published, allowing a good intussuception of the pancreas in the intestinal loop. This method has been performed in 35 duodenopancreatectomy (malignant pancreatic disease: 32 patients, benign pancreatic disease: 3 patients). The mean age of the patients was 64 years (range 34-74). There were four operative deaths unrelated to the pancreaticojejunal anastomosis and two pancreatic fistulas with spontaneous healing. The pancreatico-jejunostomy using a separate Roux en Y loop represented in this short experience a safe procedure to prevent pancreatic fistula.

Representation of cardiac tissue by a continuous electrical cable provides a simple tool to explain impulse propagation and to make a comparison between heart, skeletal muscle and nerve. Recent experimental and theoretical studies have shown, however, that the process of electrical impulse propagation in heart is complex, due to the presence of cell borders and septa of connective tissue. At sites where propagation deviates from a linear profile, action potential generation gets delayed, and in cases of decreased excitability, unidirectional block may occur. At such sites, propagation is carried by the slow Ca++ inward current, in addition to the rapid Na+ inward current. As a consequence, local propagation may become sensitive to inhibition of Ca++ channels. Moreover, computer simulations have shown that electrical cell-to-cell uncoupling an gap junctions can reverse unidirectional block at such sites to bidirectional conduction. This complex interaction between function and structure which is likely to play a major role in remodeled tissue (hypertrophy, chronic infarction) has to be taken into account in the evaluation of the mechanisms of action of antiarrhythmic drugs.

The development of a high-density active microelectrode array for in vitro electrophysiology is reported. Based on the Active Pixel Sensor (APS) concept, the array integrates 4096 gold microelectrodes (electrode separation 20 μm) on a surface of 2.5 mm x 2.5 mm as well as a high-speed random addressing logic allowing the sequential selection of the measuring pixels. Following the electrical characterization in a phosphate solution, the functional evaluation has been carried out by recording the spontaneous electrical activity of neonatal rat cardiomyocytes. Signals with amplitudes from 130 μV p-p to 300 μVp-p could be recorded from different pixels. The results demonstrate the suitability of the APS concept for developing a new generation of high-resolution extracellular recording devices for in vitro electrophysiology. © 2004 Elsevier B.V. All rights reserved.

A new bio-interface for active MEAs is presented in this paper. Unlike standard approaches that deposit MEA electrodes using post-processing of the integrated circuit, the proposed structure is based on Ti/Pt microelectrodes inserted by microfabrication into a glass interface, which is then connected to CMOS amplifiers by high density indium bumps. The concept permits construction of high density microelectrode arrays displaying high biocompatibility and, furthermore, offers the possibility to co-implement other types of detectors on the same substrate thereby allowing multiparameter, long-term measurements of biological process.