We recently showed that lovastatin attenuates cyclosporin A (CsA)-induced damage of cortical collecting duct (CCD) principal cells by reducing intracellular cholesterol. Previous studies showed that, in cell expression models or artificial membranes, exogenous cholesterol directly inhibits inward rectifier potassium channels, including Kir1.1 (Kcnj1; the gene locus for renal outer medullary K + [ROMK1] channels). Therefore, we hypothesized that lovastatin might stimulate ROMK1 by reducing cholesterol in CCD cells. Western blots showed that mpkCCD c14 cells express ROMK1 channels with molecular masses that approximate the molecular masses of ROMK1 in renal tubules detected before and after treatment with DTT. Confocal microscopy showed that ROMK1 channels were not in the microvilli, where cholesterolrich lipid rafts are located, but rather, the planar regions of the apical membrane of mpkCCD c14 cells. Furthermore, phosphatidylinositol-4,5-bisphosphate [PI(4,5)P 2 ], an activator of ROMK channels, was detected mainly in the microvilli under resting conditions along with the kinase responsible for PI(4,5) P 2 synthesis, phosphatidylinositol-4-phosphate 5-kinase, type I g [PI(4)P5K I g], which may explain the low basal open probability and increased sensitivity to tetraethylammonium observed here for this channel. Notably, lovastatin induced PI(4)P5K I g diffusion into planar regions and elevated PI(4,5)P 2 and ROMK1 open probability in these regions through a cholesterol-associated mechanism. However, exogenous cholesterol alone did not induce these effects. These results suggest that lovastatin stimulates ROMK1 channels, at least in part, by inducing PI(4,5)P 2 synthesis in planar regions of the renal CCD cell apical membrane, suggesting that lovastatin could reduce cyclosporin-induced nephropathy and associated hyperkalemia.

A novel plasma jet driven by an alternating current voltage is developed to generate atmospheric pressure non-equilibrium plasma plumes in the downstream region and in the upstream one of the argon flow. The angle between the rod electrode and the gas flow can be changed easily, and the plume lengths in the downstream and upstream regions are investigated as a function of the angle and the peak voltage. With increasing the peak voltage, the discharge pulse number tends to increase for every half voltage cycle. Using an intensified charge-coupled device camera, the dynamics of the plasma plumes is also investigated in the downstream and upstream regions. The dynamics of the plumes is qualitatively explained by the streamer propagations influenced by residual charges.

Appling a high voltage to the dielectric barrier discharge device in a coaxial geometry in flowing argon, a uniform plasma plume is generated at one atmospheric pressure. The waveforms of discharge current and the applied voltage are investigated and results indicate that both the intensity and duration width of the discharge current pulse increase with increasing the applied voltage. The gas temperature of the plasma plume is investigated by using an infrared thermometer. The gas temperature of the plasma plume are functions of gas flow rate, peak value and the frequency of the applied voltage. Results show that the gas temperature increases with increasing the applied voltage or its frequency, while it decreases with increasing the gas flow rate. A qualitative explanation is given for the variance of gas temperature as functions of the experimental parameters by analyzing the waveforms of the discharge current and the applied voltage.

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This paper reports on a new clad technology that is protective coating cladding. The method is that the Ni60 alloy was prepared on 0.45%C steel and high temperature powder paste brushed on the outside. Then the sample after being dried was heated in the high temperature resistance electric furnace. The Ni60 alloy powder on the substrate steel was melted at the appropriate temperature, and a uniform, adherent and non-dilution clad coating was obtained after optimizing the cladding parameters. The coating microstructures, compositions and microhardness were analyzed by OPM, XRD, EPMA, and microhardness testing. The experimental results show that the protective coating cladding is an efficient and economic method in cladding technologies