EuFishBioMed (COST Action BM0804): a European network to promote the use of small fishes in biomedical research.

Small fresh water fishes such as the zebrafish (Danio rerio) have become important model organisms for biomedical research. They currently represent the best vertebrate embryo models in which it is possible to derive quantitative data on gene expression, signaling events, and cell behavior in real time in the living animal. Relevant phenotypes in fish mutants are similar to those of other vertebrate models and human diseases.

Microstructured scaffolds for liver tissue cultures of high cell density: morphological and biochemical characterization of tissue aggregates.

Very high cell densities and optimal vascularization characterize among others organs and tissues in vivo. In order to study organ-specific functions in vitro or to make use of them in medical devices/treatments in the future, this natural architecture should be rebuilt. An important aspect in this context is the appropriate ratio of medium to cell volume being so far not optimally reestablished in most of the currently available in vitro systems.

Further development of microstructured culture systems and their use in tissue engineering.

The Forschungszentrum Karlsruhe aims at improving its CellChip. Its main feature is the 1 cm2 core, subdivided into 900 cubic microcontainers (300 x 300 x 300 microns). It is manufactured by injection molding using biodegradable (polylactide) as well as non-degradable (PMMA or PC) polymers.

A tissue-like culture system using microstructures: influence of extracellular matrix material on cell adhesion and aggregation.

Special microenvironmental conditions are required to induce and/or maintain specific qualities of differentiated cells. An important parameter is the three-dimensional tissue architecture that cannot be reproduced in conventional monolayer systems. Advanced tissue culture systems will meet many of these demands, but may reach their limits, especially when gradients of specific substances over distinct tissue layers must be established for long-term culture.

Cyclic AMP response in cells exposed to electric fields of different frequencies and intensities.

The action on intracellular cyclic AMP (cAMP) of therapeutically used 4000-Hz electric fields was investigated and compared with 50-Hz data. Cultured mouse fibroblasts were exposed for 5 minutes to 4000-Hz sine wave internal electric fields between 3 mV/m and 30 V/m applied within culture medium. A statistically significant decrease in cellular cAMP concentration relative to unexposed cells was observed for fields higher than 10 mV/m.