Exposure of fully differentiated L6 myotubes to a crude monokine preparation from endotoxin-stimulated RAW 264.7 cells resulted in a rapid and substantial (70%) increase in fructose 2,6-bisphosphate ...concentration coincident with a depletion of cellular glycogen and an increased lactate production. During the time required for glycogen depletion (3 hr), stimulation of 3-O-methyl-D-glucose and 2-deoxy-D-glucose uptake was initiated and observed to reach a maximum enhancement of 200% 12-15 hr later. The monokine had no effect on the Kmvalue for 2-deoxy-D-glucose uptake (1.1 mM), while Vmaxwas increased from 912 to 2400 pmol/min per mg of protein. The increase was cytochalasin B inhibitable and was dependent on protein synthesis. Photoaffinity labeling and equilibrium binding studies with 3Hcytochalasin B support the hypothesis that this increase in hexose transport was due to an increase in hexose transporters present in the plasma membrane. Purified recombinant interleukin-1α had no effect on hexose transport, whereas purified recombinant cachectin/tumor necrosis factor did stimulate hexose uptake, with half-maximal stimulation occurring at 36 nM. Although cachetin accounts for most of the biological activity associated with the crude monokine preparations, it is not the only monokine capable of inducing glucose transport in L6 cells. Specific immunoabsorption of cachectin/tumor necrosis factor from the crude monokine preparation revealed a monokine that had a similar bioactivity at extremely low concentrations on L6 cells.
Atlas is a facility being designed at Los Alamos National Laboratory (LANL) to perform high-energy-density experiments in support of weapon physics and basic research programs. It is designed to be ...an international user facility, providing experimental opportunities to researchers from national laboratories and academic institutions. For hydrodynamic experiments, it will be capable of achieving a pressure exceeding 30 Mbar in a several cubic centimeter volume. With the development of a suitable opening switch, it will be capable of producing more than 3 MJ of soft X-rays. The capacitor bank design consists of a 36 MJ array of 240 kV Marx modules. The system is designed to deliver a peak current of 45-50 MA with a 4-5-/spl mu/s rise time. The Marx modules are designed to be reconfigured to a 480-kV configuration for opening switch development. The capacitor bank is resistively damped to limit fault currents and capacitor voltage reversal. An experimental program for testing and certifying prototype components is currently under way. The capacitor bank design contains 300 closing switches. These switches are a modified version of a railgap switch originally designed for the DNA-ACE machines. Because of the large number of switches in the system, individual switch prefire rates must be less than 10/sup -4/ to protect the expensive target assemblies. Experiments are under way to determine if the switch-prefire probability can be reduced with rapid capacitor charging.
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