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“Oxygen is essential for life, and cells have therefore developed numerous adaptive responses to oxygen change. Here, we examined the difference in oxygen-control functions of human (HE), mouse (ME), and Syrian hamster embryo (SHE) cells cultured under different oxygen conditions (0.5%, 2% and 20%), and also examined

whether oxygen tensions contributed to cellular lifespan and transformation. HE cells had their replicative lifespan slightly extended under hypoxic (0.5% and 2% oxygen) conditions, but were not immortalized under any of the oxygen concentrations. On the other hand, although ME cells cultured under 20% oxygen tension decreased their proliferation potency temporarily at early stage, all rodent cells were immortalized and acquired anchorage-independency, regardless of oxygen tension. These results suggest that cellular oxygen control function is MK2206 related to sensitivities cellular immortalization and transformation.

To understand intervention of oxygen control ability on cellular immortalization and transformation, we examined the intracellular oxidative level, mitochondria functions and radiation sensitivity. Intracellular oxidative levels of hypoxically cultured rodent cells were significantly enhanced. GSK2879552 solubility dmso Mitochondrial membrane potential wits altered depend on oxygen tensions, but the change was not parallel to mitochondria number

in rodent cells. ME cells were particularly sensitive to oxygen change, and showed 3-Methyladenine cell line a clear oxygen effect on the X-ray survival. However, there was no difference in frequency of radiation-induced micronuclei between HE and ME cells. These results suggest that the response to oxygen change differs markedly in HE and rodent cells.”
“The shock pressure generated by the glass confined regime in laser shock peening and its attenuation in the target material are investigated. First, the particle velocity of the target back free surface induced by laser generated shock pressure of this regime is measured using a photonic Doppler velocimetry system. The temporal profile of the particle velocity at the back free surface, where the elastic precursor is captured, manifests a powerful diagnostic capability of this newly developed photonic Doppler velocimetry system for tracking the velocity on short time scales in shock-wave experiments. Second, a coupling pressure analytical model, in which the material constitutive models of confined layers and target material are considered, is proposed to predict the plasma pressure profile at the surface of target. Furthermore, using the predicted shock pressure profile as the input condition, the dynamic response of the target under the shock pressure is simulated by LS-DYNA.