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Aims. We aimed to investigate whether LCZ696 protects against pathological cardiac hypertrophy by regulating the Sirt3/MnSOD pathway. Methods. In vivo, we established a transverse aortic constriction animal model to establish pressure overload-induced heart failure. Subsequently, the mice were given LCZ696 by oral gavage for 4 weeks. After that, the mice underwent transthoracic echocardiography before they were sacrificed. In vitro, we introduced phenylephrine to prime neonatal rat cardiomyocytes and small-interfering RNA to knock down Sirt3 expression. Results. Pathological hypertrophic stimuli caused cardiac hypertrophy and fibrosis and reduced the expression levels of Sirt3 and MnSOD. LCZ696 alleviated the accumulation of oxidative reactive oxygen species (ROS) and cardiomyocyte apoptosis. Furthermore, Sirt3 deficiency abolished the protective effect of LCZ696 on cardiomyocyte hypertrophy, indicating that LCZ696 induced the upregulation of MnSOD and phosphorylation of AMPK through a Sirt3-dependent pathway. Conclusions. LCZ696 may mitigate myocardium oxidative stress and apoptosis in pressure overload-induced heart failure by regulating the Sirt3/MnSOD pathway.

The performance of manganin resistance gauges under high static pressure is evaluated. The accuracy of several interpolation- (or extrapolation-) based mathematical-models is compared. It is shown that if the gauges used at pressures below 1 GPa are calibrated at a given constant temperature and used at that temperature, the complete mathematical-model is unnecessary. However, a complete model for the variation of resistance with both pressure and temperature is required in the pressure range from 1 GPa up to 20 GPa, because the temperature changes due to compression or expansion of the pressure-transmitting medium can be quite pronounced. >

The high-static-pressure metrological characteristics of 1-GPa manganin resistance gauges are investigated. Nonlinearity is measured by means of a secondary standard-free piston gauge. A second-order mathematical-model is established, with an interpolation accuracy reaching 0.07%, as verified by calibration tests. The results obtained indicate that manganin resistance gauges exhibit very good stability, repeatability, and reproducibility. >

A new high temperature transducer is described. The transducer employs NiCr-NiSi thermocouple as a sensing-element and can directly measure flash surface temperature at 1230/spl deg/C under high pressure up to 400 MPa. It can be reused by abrading the hot-junction after it ablated. The response time constant is less than 1 /spl mu/s which was verified by theoretical calculation and by a calibrated test. This paper relates to the features of the transducer and the technology keys to the design of high-pressure-withstand poles, micrometer-order clearance between poles and high-resistance insulation. The theoretical analysis and calibration test are presented. The measurement results and curves of the inner-barrel surface temperature for a certain gun are given. >

A new type of high temperature withstanding high pressure transducer is described. The transducer uses Manganin wire as sensing-element and can measure pressure up to 250 MPa under condition of high temperature up to 200/spl deg/C for a long time. The expanded uncertainty in measurement of the transducer is less than 1.0% verified by calibration and practical use. This paper discusses the key technology issues, such as high pressure sealing and linearity correction under the temperature range from 0/spl deg/C to 200/spl deg/C, etc. The calibration test under high temperature condition is carried out against a free piston gauge having an uncertainty of 0.1%. Measured results in practical use on high-pressure cauldrons for growing man-made crystals are given.