Combined Exposure to Simulated Microgravity and Acute or Chronic Radiation Reduces Neuronal Network Integrity and Survival.

During orbital or interplanetary space flights, astronauts are exposed to cosmic radiations and microgravity. However, most earth-based studies on the potential health risks of space conditions have investigated the effects of these two conditions separately. This study aimed at assessing the combined effect of radiation exposure and microgravity on neuronal morphology and survival in vitro.

MorphoNeuroNet: an automated method for dense neurite network analysis.

High content cell-based screens are rapidly gaining popularity in the context of neuronal regeneration studies. To analyze neuronal morphology, automatic image analysis pipelines have been conceived, which accurately quantify the shape changes of neurons in cell cultures with non-dense neurite networks. However, most existing methods show poor performance for well-connected and differentiated neuronal networks, which may serve as valuable models for inter alia synaptogenesis.

Morphological and physiological changes in mature in vitro neuronal networks towards exposure to short-, middle- or long-term simulated microgravity.

One of the objectives of the current international space programmes is to investigate the possible effects of the space environment on the crew health. The aim of this work was to assess the particular effects of simulated microgravity on mature primary neuronal networks and specially their plasticity and connectivity. For this purpose, primary mouse neurons were first grown for 10 days as a dense network before being placed in the Random Positioning Machine (RPM), simulating microgravity.

Non-conventional apoptotic response to ionising radiation mediated by N-methyl D-aspartate receptors in immature neuronal cells.

During cortical development, N-methyl D-aspartate (NMDA) receptors are highly involved in neuronal maturation and synapse establishment. Their implication in the phenomenon of excitotoxicity has been extensively described in several neurodegenerative diseases due to the permissive entry of Ca2+ ions and massive accumulation in the intracellular compartment, which is highly toxic to cells. Ionising radiation is also a source of stress to the cells, particularly immature neurons.

Different responsiveness of endothelial cells to vascular endothelial growth factor and basic fibroblast growth factor added to culture media under gravity and simulated microgravity.

When incubated under simulated microgravity (s-microg), endothelial cells (EC) form tubular structures that resemble vascular intimas. This delayed formation of 3D EC structures begins between the 5th and 7th day of culturing EC under conditions of s-microg, when double-row cell assemblies become visible. With the aim of learning about this initial phase of tubular structure formation, we found that NFkappaBp65 protein content was similar in all cell populations, but gene and protein expression of phosphokinase A catalytic subunit, phosphokinase Calpha, and extracellular signal-regulated kinases 1 and 2 was altered in cells cultured under s-microg.

Mitigation of a radon-rich Belgian dwelling using active subslab depressurization.

In a radon prone area in Belgium, a dwelling with high indoor radon concentrations was identified through a passive measurement. Next, a continuous, active radon monitoring device was installed for one month. A 20-a retrospective radon assessment was also performed.

Developmental abnormalities induced by X-irradiation in p53 deficient mice.

In order to assess the influence of p53 inactivation on radiation-induced developmental effects, male mice heterozygous for the wild-type p53 allele (mimicking the human Li-Fraumeni syndrome) were crossed with C57BL females, and their heterozygous p53+/- progeny were mated with each other to obtain p53+/-, p53-/- and p53+/+ embryos. Pregnant females were X-irradiated with 0.5 Gy on days 1 (pre-implantation period), 8 or 11 (organogenesis period) of gestation.