Nonesterified fatty acids such as oleate and palmitate acutely potentiate insulin secretion from pancreatic islets in a glucose-dependent manner. In addition, recent studies show that fatty acids elevate intracellular free Ca(2+) and increase voltage-gated Ca(2+) current in mouse beta-cells, although the mechanisms involved are poorly understood. Here we utilized a heterologous system to expres...

Within cardiomyocytes, endothelial nitric oxide synthase (eNOS) and neuronal nitric oxide synthase (nNOS) are thought to modulate L-type calcium channel (LTCC) function and sarcoplasmic reticulum calcium cycling, respectively. However, divergent results from mostly invasive prior studies suggest more complex roles. To elucidate the roles of nNOS and eNOS in vivo, we applied noninvasive cardiac ...

Cardiac diseases persistently increase the contractility demands of cardiac myocytes, which require activation of the sympathetic nervous system and subsequent increases in myocyte Ca(2+) transients. Persistent exposure to sympathetic and/or Ca(2+) stress is associated with myocyte death. This study examined the respective roles of persistent beta-adrenergic receptor (beta-AR) agonist exposure ...

It is well established that L-type calcium channels (LTCCs) are expressed in astroglia. However, their functional role is still speculative, especially under pathologic conditions. We recently showed that the α1 subunit-like immunoreactivity of the CaV1.2 channel is strongly expressed in reactive astrocytes around beta-amyloid plaques in 11-month-old Alzheimer transgenic (tg) mice with the amyl...

Hypertension is nearly universal yet poorly controlled in the elderly despite proven benefits of intensive treatment. Mice lacking mineralocorticoid receptors in smooth muscle cells (SMC-MR-KO) are protected from rising blood pressure (BP) with aging, despite normal renal function. Vasoconstriction is attenuated in aged SMC-MR-KO mice, thus they were used to explore vascular mechanisms that may...

This paper presents a novel approach to design a parametric RF stop band pass filter based on Low Temperature Co-fired Ceramic (LTCC) Technology. The LTCC technology enables to miniaturize and development compact structures using not only the standard xy-planar circuit dimensions but also the zheight dimension. The proposed filters topologies are based on a stripline loaded with one or several ...

Electronics packaging evolution involves both architectural and technology considerations. In this paper, we present the design and measurements of Single-Input-SingleOutput (SISO) dual-band filters operating at ISM 2.4-2.5 GHz and UNII 5.15-5.85 GHz frequency bands, using the novel ”dual behavior resonators” technique. The filters have been fabricated using Low Temperature Co-fired Ceramic (LT...

The concept of localized signalling in the coupling between L-type Ca2+ channels, LTCC, in the sarcolemma and ryanodine receptors, RyR, in the sarcoplasmic reticulum was introduced in the late 1980s to address one of the conundrums of excitation–contraction coupling. The tightly regulated Ca2+ signals observed in isolated cardiac myocytes under voltage clamp conditions, or in skinned myocytes, ...

Abnormal L-type Ca(2+) channel (LTCC, also named Cav1.2) density and regulation are important contributors to depressed contractility in failing hearts. The LTCC agonist BAY K 8644 (BAY K) has reduced inotropic effects on failing myocardium. We hypothesized that BAY K effects on the LTCC current (I(CaL)) in failing myocytes would be reduced because of increased basal activity. Since support of ...

The thesis describes the development of a novel LTCC material system for RF and microwave telecommunication purposes. The work has been divided into three parts. In the first section, the compositional and firing properties of this novel LTCC dielectric have been studied as well as its thermomechanical and dielectric properties. The second section describes the multilayer component preparation ...