A new in vitro model to study cellular responses after thermomechanical damage in monolayer cultures.

Although electrosurgical instruments are widely used in surgery to cut tissue layers or to achieve hemostasis by coagulation (electrocautery), only little information is available concerning the inflammatory or immune response towards the debris generated. Given the elevated local temperatures required for successful electrocautery, the remaining debris is likely to contain a plethora of compounds entirely novel to the intracorporal setting. A very common in vitro method to study cell migration after mechanical damage is the scratch assay, however, there is no established model for thermomechanical damage to characterise cellular reactions.

Rationale, bench testing and in vivo evaluation of a novel 5 mm laparoscopic vessel sealing device with homogeneous pressure distribution in long instrument jaws.

Background: In 1998, an electrothermal bipolar vessel sealing (EBVS) system was introduced and quickly became an integral component of the surgical armamentarium in various surgical specialties. Currently available EBVS instruments use a scissor-like jaw configuration and closing mechanism, which causes decreasing compression pressure from the proximal to the distal end of the jaws. A new EBVS system is described here which utilizes a different instrument jaw configuration and closing mechanism to enable a more homogeneous pressure distribution despite longer instrument jaws.

Light induced stimulation and delay of cardiac activity.

This article shows the combination of light activatable ion channels and microelectrode array (MEA) technology for bidirectionally interfacing cells. HL-1 cultures, a mouse derived cardiomyocyte-like cell line, transfected with channelrhodopsin were stimulated with a microscope coupled 473 nm laser and recorded with custom built 64 electrode MEAs. Channelrhodopsin induced depolarization of the cell can evoke action potentials (APs) in single cells.

Iridium oxide microelectrode arrays for in vitro stimulation of individual rat neurons from dissociated cultures.

We present the first in vitro extracellular stimulation of individual neurons from dissociated cultures with iridium oxide (IrO(x)) electrodes. Microelectrode arrays with sputtered IrO(x) films (SIROF) were developed for electrophysiological investigations with electrogenic cells. The microelectrodes were characterized with scanning electron and atomic force microscopy, revealing rough and porous electrodes with enlarged surface areas.