Prevailing models postulate that high Ca(2+) selectivity of Ca(2+) release-activated Ca(2+) (CRAC) channels arises from tight Ca(2+) binding to a high affinity site within the pore, thereby blocking monovalent ion flux. Here, we examined the contribution of high affinity Ca(2+) binding for Ca(2+) selectivity in recombinant Orai3 channels, which function as highly Ca(2+)-selective channels when ...

Received 10/11/2004; revised 11/8/2004; accepted 11/12/2004. For correspondence or reprints contact: Guang-Uei Hung, M.D., Department of Nuclear Medicine, Changhua Christian Hospital, 135 Nan-Shiao Street, Changhua 500, Taiwan. Tel: (886)4-7238595 ext. 3091, Fax: (886)4-7232942, E-mail: [email protected] Background: Gated myocardial perfusion single photon emission computed tomography (SPECT) h...

Purpose Many sick adults and children are unable to perform long breath-holds required for conventional, Cartesian phase-contrast (PC) sequences. Using a prospectivelytriggered spiral PCMR sequence accelerated with sensitivity encoding (SENSE), it should be possible to achieve high resolution PCMR data in a short breath-hold. The aim of this study was to compare flow volumes measured using: a) ...

A woman with coronary artery disease underwent a new imaging technique: dobutamine-stress electrocardiography (ECG)-gated tetrofosmin-single photon emission computed tomography (SPECT). Dobutamine-stress ECG-gated tetrofosmin-SPECT with automatic left ventricular function analysis software programs detected improvement and a biphasic response of dysfunctional myocardium during dobutamine infusi...

A method for summing together datasets from gated cardiac PET acquisitions is described. Optical flow techniques are used to accurately model non-rigid motion present during the cardiac cycle so that a one-to-one mapping is found between each voxel of two gated volumes. Using this mapping, image summing can take place, producing a composite dataset with improved statistics and reduced motion-in...

It is of value to determine the amount of viable myocardial tissue in patients suffering from chronic coronary artery disease and ventricular dysfunction. Having the capability of evaluating both myocardial perfusion and function, simultaneously, myocardial scanning by ECG-Gated is an appropriate method for this purpose. The aim of this study was to compare the results of myocardial perfu...

Buthotus schach is one of the dangers scorpion in Iran that belong to the Buthidae family. Toxins are existing in venom scorpion, modulate the ion channels by blocking or opening the pore of the channel or by altering the voltage gating and useful as pharmacological tools. In the present study, we investigated the effect of venom and its obtained fractions by gel filtrations on electrophysiolog...

The M/C/1 queue with multiple vacations and gated service discipline is considered. We first provide an alternative approach to derive the Laplace-Stieltjes transform of the limiting waiting time distribution, which reveals the stochastic structure of the gated vacation system. Next we discuss the regenerative cycle of the gated vacation system. Based on these considerations, we carry our a tim...