Automated culture system experiments hardware: developing test results and design solutions.

The experiment proposed by Prof. Ricci University of Milan is funded by ASI with Laben as industrial Prime Contractor. ACS-EH (Automated Culture System-Experiment Hardware) will support the multigenerational experiment on weightlessness with rotifers and nematodes within four Experiment Containers (ECs) located inside the European Modular Cultivation System (EMCS) facility..Actually the Phase B is in progress and a concept design solution has been defined. The most challenging aspects for the design of such hardware are, from biological point of view the provision of an environment which permits animal's survival and to maintain desiccated generations separated and from the technical point of view, the miniaturisation of the hardware itself due to the reduce EC provided volume (160mmx60mmx60mm). The miniaturisation will allow a better use of the available EMCS Facility resources (e.g. volume. power etc.) and to fulfil the experiment requirements. ACS-EH, will be ready to fly in the year 2005 on boar the ISS.

Bone as an ion exchange system: evidence for a link between mechanotransduction and metabolic needs.

To detect whether the mutual interaction occurring between the osteocytes-bone lining cells system (OBLCS) and the bone extracellular fluid (BECF) is affected by load through a modification of the BECF-extracellular fluid (ECF; systemic extracellular fluid) gradient, mice metatarsal bones immersed in ECF were subjected ex vivo to a 2-min cyclic axial load of different amplitudes and frequencies. The electric (ionic) currents at the bone surface were measured by a vibrating probe after having exposed BECF to ECF through a transcortical hole. The application of different loads and different frequencies increased the ionic current in a dose-dependent manner. The postload current density subsequently decayed following an exponential pattern. Postload increment's amplitude and decay were dependent on bone viability. Dummy and static loads did not induce current density modifications. Because BECF is perturbed by loading, it is conceivable that OBLCS tends to restore BECF preload conditions by controlling ion fluxes at the bone-plasma interface to fulfill metabolic needs. Because the electric current reflects the integrated activity of OBLCS, its evaluation in transgenic mice engineered to possess genetic lesions in channels or matrix constituents could be helpful in the characterization of the mechanical and metabolic functions of bone.