Herein we demonstrate how nanojunctions between lysosomes and sarcoplasmic reticulum (L-SR junctions) serve to couple lysosomal activation to regenerative, ryanodine receptor-mediated cellular Ca (2+) waves. In pulmonary artery smooth muscle cells (PASMCs) it has been proposed that nicotinic acid adenine dinucleotide phosphate (NAADP) triggers increases in cytoplasmic Ca (2+) via L-SR junctions...

In an article of a few years ago [2] Kerékjartó obtained interesting results about certain types of transformations which he called similitudes. With a few modifications and extensions his methods can be used to gain information about the structure of measure preserving transformations at fixed points. For simplicity the results are formulated for Euclidean w-space although they could easily be...

Let { n} be a system of monic polynomials orthogonal on the unit circle with respect to a positive Borel measure p.. It is shown that under .fairly mild conditions on the reflection coefficients, n(O), the zeros of a subsequence of { n} are asymptotically uniformly distributed on some circle. The radius of this circle can be found using a Cauchy-Hadamard-type formula. We also character...

Calcium plays two pivotal roles in cardiac excitationcontraction (E-C) coupling.1 Ca drives myofilament activation and carries or regulates ionic currents that are responsible for normal electrical rhythms2 as well as life-threatening arrhythmias.3 In this editorial, I will focus on Ca and pacemaker activity and arrhythmogenesis. Ca entry via Ca current (ICa) triggers sarcoplasmic reticulum (SR...

Let Q denote the rationals, P the irrationals, C the Cantor set and L the space C {p} (where p e C). Let / : X —> Y be a perfect continuous surjection. We show: (1) If X G { Q , P, QxP} , or if / is irreducible and Xe{C, L}, then Y is homeomorphic to X if Y is zero-dimensional. (2) If X G {P, C, L} and / is irreducible, then there is a dense subset S of Y such that / | /*~[S] is a homeomorphism...

OBJECTIVES The drug K201 (JTV-519) increases inotropy and suppresses arrhythmias in failing hearts, but the effects of K201 on normal hearts is unknown. METHODS The effect of K201 on excitation-contraction (E-C) coupling in normal myocardium was studied by using voltage-clamp and intracellular Ca(2+) measurements in intact cells. Sarcoplasmic reticulum (SR) function was assessed using permeab...

The concepts of L-fuzzy ideal generated by a L-fuzzy subset, L-fuzzy prime and completely prime ideal where L is a complete lattice are considered and some results are proved

Objective: After-depolarization associated arrhythmias are frequently observed in heart failure and associated with spontaneous calcium release from sarcoplasmic reticulum (SR), calcium after-transients. We hypothesize that disturbed SR calcium handling underlies calcium after-transients in heart failure (HF). Methods: We measured the stimulation rate dependence (0.2–3 Hz) of diastolic calcium,...

Bondarenko, Vladimir E., Glenna C. L. Bett, and Randall L. Rasmusson. A model of graded calcium release and L-type Ca channel inactivation in cardiac muscle. Am J Physiol Heart Circ Physiol 286: H1154–H1169, 2004;10.1152/ajpheart.00168.2003.—We have developed a model of Ca handling in ferret ventricular myocytes. This model includes a novel L-type Ca channel, detailed intracellular Ca movements...