Background-Apoptosis repressor with caspase recruitment domain (ARC) is abundantly expressed in cardiomyocytes.Protein kinase CK2 can phosphorylate ARC at threonine-149, thereby enabling ARC to antagonize apoptosis. ARC phosphorylation occurs in a constitutive manner. Nevertheless, cardiomyocytes still undergo apoptosis that is related to cardiac diseases such as myocardial infarction and heart failure. Whether the occurrence of apoptosis is related to the loss of protection by ARC under pathological conditions remains unknown. Methods and Results-ARC phosphorylation levels are decreased in cardiomyocytes treated with isoproterenol or aldosterone. We explored the molecular mechanism by which ARC phosphorylation levels are decreased. Our results reveal that either direct incubation or coexpression with calcineurin leads to a decrease in ARC phosphorylation levels. Inhibition of calcineurin can attenuate the reduction in ARC phosphorylation levels on treatment with isoproterenol or aldosterone. These data indicate that the reduction in ARC phosphorylation levels is related to its dephosphorylation by calcineurin. Our results further reveal that ARC can prevent isoproterenol-and aldosterone-induced apoptosis, but this function depends on its phosphorylation status. Isoproterenol and aldosterone upregulate Fas ligand expression, and Fas ligand and caspase-8 are required for isoproterenol and aldosterone to induce apoptosis. However, phosphorylated but not dephosphorylated ARC is able to inhibit caspase-8 -mediated apoptosis. Phosphorylated ARC exerts its effects against caspase-8 by directly associating with procaspase-8 and inhibiting its interaction with Fas-associated protein with death domain. Conclusions-Our study identifies a novel cardiac apoptotic pathway in which ARC is dephosphorylated by calcineurin.This pathway could be a component in the cardiac apoptotic machinery. (Circulation. 2008;118:2268-2276.)

Vertically-aligned carbon nanotube forests (VACNTs) with excellent axial heat dissipation properties were formed on aluminum foil to dissipate heat. In addition, the heat dissipation efficiency of aluminum–VACNTs composites in this work was compared with that of commercially available mainstream thermal sheets under the same natural cooling conditions. Chemical vapor deposition (CVD) was employed as a synthesis method using a three-segment high-temperature furnace. Subsequently, the temperature changes in a heating body with the aluminum–VACNTs composites was measured over time subject to natural cooling. In addition, the performance was compared with copper and pyrolytic graphite sheets. The experimental results revealed that the heat dissipation efficiency of the flexible aluminum–VACNTs composites was higher than that of clean aluminum foil, a copper sheet, and a pyrolytic graphite sheet by up to 56%, 40%, and 20%, respectively. Moreover, this work also verified the height of the carbon nanotube (CNT) did not influence the heat dissipation efficiency, indicating that the time cost of synthesis could be reduced.

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During dental sinus lift surgery, it is important to monitor the thickness of the remaining maxilla to avoid perforating the sinus membrane. Therefore, a sensor should be integrated into ultrasonic dental tools to prevent undesirable damage. This paper presents a piezoelectric (PZT) sensor installed in an ultrasonic transducer to measure the stiffness of high and low materials. Four design types using three PZT ring materials and a split PZT for actuator and sensor ring materials were studied. Three sensor locations were also examined. The voltage signals of the sensor and the displacement of the actuator were analyzed to distinguish the low and high stiffness. Using sensor type T1 made of the PZT-1 material and the front location A1 provided a high sensitivity of 2.47 Vm/kN. The experimental results demonstrated that our design can measure soft and hard stiffness.