Objectives: Visualizing myocardium with near field ultrasound (NFUS) transducers in the tip of the catheter might provide an image of the evolving pathological lesion during energy delivery.
Background: Radiofrequency (RF) catheter ablation has been effective in arrhythmia treatment, but no technology has allowed lesion formation to be visualized in real time in vivo.
Methods: RF catheter ablations were performed in vivo with the goal to create transmural atrial lesions and large ventricular lesions.
Background: Safe and successful radiofrequency catheter ablation depends on creation of transmural lesions without collateral injury to contiguous structures. Near-field ultrasound (NFUS) imaging through transducers in the tip of an ablation catheter may provide important information about catheter contact, wall thickness, and ablation lesion formation.
Methods And Results: NFUS imaging was performed using a specially designed open-irrigated radiofrequency ablation catheter incorporating 4 ultrasound transducers.
Identification of singleton P2X7 inhibitor 1 from HTS gave a pharmacophore that eventually turned into potential clinical candidates 17 and 19. During development, a number of issues were successfully addressed, such as metabolic stability, plasma stability, GSH adduct formation, and aniline mutagenicity. Thus, careful modification of the molecule, such as conversion of the 1,4-dihydropyridinone to the 1,2-dihydropyridinone system, proper substitution at C-5″, and in some cases addition of fluorine atoms to the aniline ring allowed for the identification of a novel class of potent P2X7 inhibitors suitable for evaluating the role of P2X7 in inflammatory, immune, neurologic, or musculoskeletal disorders.
View Article and Find Full Text PDFIn the cochlea, Reissner's membrane separates the scala media endolymphatic compartment that sustains the positive endocochlear potential and ion composition necessary for sound transduction, from the scala vestibuli perilymphatic compartment. It is known that with sustained elevated sound levels, adenosine 5'-triphosphate (ATP) is released into the endolymph and ATP-gated ion channels on the epithelial cells lining the endolymphatic compartment shunt the electrochemical driving force, contributing to protective purinergic hearing adaptation. This study characterises the properties of epithelial cell P2X(2)-type ATP-activated membrane conductance in the mouse Reissner's membrane, which forms a substantial fraction of the scale media surface.
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