The renin-angiotensin system plays an important role in the pathogenesis of cardiac hypertrophy and chronic heart failure as angiotensin II has been shown to induce cardiac hypertrophy and fibrosis. ...Besides these structural alterations, functional effects on cardiomyocytes have been reported in different mammalian species. Angiotensin II is known to produce a positive inotropic effect in some species, and differences in atrial and ventricular myocardium have been described. So far, the molecular events which govern angiotensin II-mediated changes in cardiac contractility are not completely understood. In order to study the dependency of the angiotensin II-induced positive inotropic effect on receptor density, we examined the effect of angiotensin II on cardiac function in atria, papillary muscles and isolated ventricular cardiomyocytes from adult Sprague-Dawley rats and TGR(αMHC-hAT
1) transgenic rats, which expressed the human angiotensin AT
1 receptor (hAT
1) specifically in the heart. In atrial myocardium from adult Sprague-Dawley rats, angiotensin II (30 μmol/l) produced an AT
1-mediated positive inotropic effect (38.5% of control), whereas in papillary muscles and isolated ventricular myocytes, no inotropic response was observed. As shown by polymerase chain reaction (PCR) and radioligand binding, the human angiotensin AT
1 receptor was exclusively expressed in transgenic animals, which markedly overexpressed the angiotensin AT
1 receptor. However, in transgenic rats the positive inotropic effect in atrial preparations was similar to the controls, and neither in papillary muscles nor in isolated cardiomyocytes the increase in receptor density led to an inotropic effect induced by angiotensin II. These data suggest that the existence of functionally uncoupled receptors rather than the low density of receptors at the ventricular site is responsible for the inability of ventricular myocardium to respond to angiotensin II.
Many years of research on dependable, fault-tolerant software systems yielded a myriad of tool implementations for vulnerability analysis and experimental validation of resilience measures. Trace ...recording and fault injection are among the core functionalities these tools provide for hardware debuggers or system simulators, partially including some means to automate larger experiment campaigns. We argue that current fault-injection tools are too highly specialized for specific hardware devices or simulators, and are developed in poorly modularized implementations impeding evolution and maintenance. In this article, we present a novel design approach for a fault-injection infrastructure that allows experimenting researchers to switch simulator or hardware back ends with little effort, fosters experiment code reuse, and retains a high level of maintainability.
The Free Electron Laser in Hamburg (FLASH) is a large scale user facility, providing highly stable and brilliant laser pulses down to a wavelength of 4.1 nm. Essential for stable and reproducible ...photon beam is the precision control of the electron bunch parameters. The acceleration principle of the electron bunches at FLASH is based on superconducting RF technology (SRF), in which the RF fields are controlled by a digital low level RF (LLRF) system. This system has been recently upgraded to the Micro Telecommunication Computing Architecture (MicroTCA.4) to improve the performance of the field regulation. This paper presents the first measurements and operation experiences using this new electronic crate standard at a large scale research facility. RF field regulation is carried out by real time fast digital processing on several boards in a MicroTCA.4 crate, and slow automation routines running on a dual core i7 front-end CPU. Scalability and modularity of this system is one of the key parameters to meet the next steps, namely being the platform standard for the European X-ray free electron laser currently build at DESY.
Seven protein kinase CK2 a clones were isolated from a murine genomic DNA library. They were assigned to four different genomic loci (A,B,C,D). Locus D was previously identified as a processed ...pseudogene (Boldyreff et al. (1992) Biochem. Biophys. Res. Commun. 186, 723–730). Here we present sequences of genomic loci B and C and the murine CK2 α cDNA. Loci B and C are like locus D processed pseudogenes, however, with considerable differences among each other and to the cDNA, especially with respect to the lengths of the putative gene products. Genomic locus D would code for a protein of 82 amino acids, locus B for a protein of 132 amino acids and locus C product for the full length product of 391 amino acids as the murine cDNA.
PDF
