No abstract

The clinostat was originally used to find out why plant roots appear to grow predominantly toward the center of the Earth. Over the last 2-3 decades, slow- and fast-rotating 2D and 3D clinostats have been used to assess cellular adaptation to this environment. A cell culture is placed in a spin module of the clinostat platform and its rotation is set empirically (2-3 rpm). The machine is then allowed to run for a specified period (hours to days) after which the cultures are removed and assayed for specific properties, such as cell growth, size and shape, distribution of receptors, integrity of the cytoskeleton or gene expression. A 3D clinostat was developed by the Microgravity Laboratory/IPCT-PUCRS group and validated by the Stem Cell Group of Kingston University London, which used 4 different types of human cancer cells and cord blood stem cells (CBSC). After rotation for 19h at 37degC, 5%CO2 humidified atmosphere, the 3D clinostat significantly improved proliferation potential of all tested cell populations when compared to static cultures. After only 5 days, high definition microscopic analysis revealed that all CBSC adhered and expanded onto the BDtrade 3D collagen composite scaffolds, and cross-developed into hepatocyte-like cells upon stimulation.

No abstract

Preservation of astronaut crew health during an exploration mission to the Moon or Mars will be crucial to mission success. The likelihood of a life-threatening medical condition occuring during a mission to Mars has been estimated by NASA to be 1% per year (Johnston, 1998; Johnston, Campbell, Billica, & Gilmore, 2004). Since basic life support is a vital skill in critical care medicine, plans must be in place for cardiopulmonary resuscitation in both microgravity and hypogravity (i.e., on the surface of the Moon or Mars). Following the design of a body suspension device to simulate a hypogravity environment, subjects performed external chest compressions in 1G, 0.17G (Lunar), 0.38G (Mars), and 0.7G (Planet X). Chest compression adequacy was assessed by means of rate and depth. Heart rate immediately before and after three minutes of chest compression gave a measure of rescuer fatigue. Elbow flexion was measured using an electrogoniometer in order to assess the use of arm muscles to achieve chest compressions. This study found that the mean depth (Lunar and Mars) and rate (Mars) of chest compression was below American Heart Association recommendations during hypogravity simulation in the female group. Furthermore, elbow flexion proved to be significantly greater during Lunar and Mars hypogravity simulation than that of the 1G control condition, suggesting that upper arm force may be used to counter the loss of body weight in an attempt to maintain adequate chest compression under these conditions.

Preservation of astronaut crew health during an exploration mission to the Moon or Mars will be crucial to mission success. The likelyhood of a life threatening medical condition occurring during a mission to Mars has been estimated by NASA to be 1% per year. Since basic life support is a vital skill in critical care medicine, plans must be in place for cardiopulmonary resuscitation in both microgravity and hypogravity (i.e. on the surface of the Moon or Mars). Following the design of a body suspension device to simulate a hypogravity environment, subjects performed external chest compressions in 1G, 0.17G (Lunar), 0.38G (Mars) and 0.7G ('Planet X'). Chest compression adequacy was assessed by means of rate and depth. Heart rate immediately before and after 3 minutes of chest compression gave a measure of rescuer fatigue. Elbow flexion was measured using an electrogoniometer in order to assess the use of arm muscles to achieve chest compressions. This study found that depth (Lunar and Mars) and rate (Mars) of chest compression was below American Heart Association recommendations during hypogravity simulation in the female group. Furthermore, elbow flexion proved to be significantly greater during Lunar and Mars hypogravity simulation than that of the 1G control condition, suggesting that upper arm force may be used to counter the loss of body weight in an attempt to maintain adequate chest compression under these conditions.