BACKGROUND Percutaneous cryoballoon ablation is a commonly used procedure to treat atrial fibrillation. One of the major limitations of the procedure is the inability to directly visualize tissue damage and functional gaps between the lesions. We seek to develop an approach that will enable real-time visualization of tissue necrosis during cryo- or radiofrequency ablation procedures. METHODS ...

The ability of cholinergic agonists to activate phospholipase C in bovine adrenal chromaffin cells was examined by assaying the production of inositol phosphates in cells prelabeled with [3H]inositol. We found that both nicotinic and muscarinic agonists increased the accumulation of [3H]inositol phosphates (mainly inositol monophosphate) and that the effects mediated by the two types of recepto...

The level of inositol phosphates was measured in rat hepatocytes treated with 2-methyl-1,4-naphthoquinone (menadione) or tert-butyl hydroperoxide, which cause Ca2+ mobilization from intracellular stores and an increase in cytosolic free Ca2+ concentration. Although neither agent produced any apparent changes in the resting level of inositol phosphates, pretreatment of hepatocytes with either me...

Polyprenyl phosphates, as well as polyprenyl alcohols bearing different isopentenyl C(5) units, have been synthesized. The pH range of spontaneous vesicle formation of polyprenyl phosphates with or without polyprenyl alcohols was defined by fluorescence microscopy. A variety of the acyclic or monocyclic polyprenyl phosphates studied formed stable vesicles in water over a wide range of pHs, and ...

Molecular complexes in the ratio 1:1 were formed in aqueous solution between various methoxysubstituted phenylisopropylamine (amphetamine) hydrochloride or oxalate salts and riboflavin deri­ vatives (flavin mononucleotide and flavin adenine dinucleotide). The association constants for these complexes were determined by the fluorescence quenching method as well as by the absorption method. The n...

CD spectroscopy and PAGE were used to cooperatively analyze melting conformers of DNA strands containing GA and TA dinucleotide repeats. The 20mer (GA)10 formed a homoduplex in neutral solutions containing physiological concentrations of salts and this homoduplex was not destabilized even in the terminal (GA)3 hexamers of (GA)3(TA)4(GA)3, although the central (TA)4 portion of this oligonucleoti...

The interest in electrocrystallization of calcium phosphates (CaP) in general, and of hydroxyapatite (HAp) specifically, results from the promising industrial benefits, unique microstructures, and properties of the deposits produced by this process, and the possible similarity to bone mineralization in vivo. In this paper, our work on electrocrystallization of HAp and octacalcium phosphate (OCP...

Coupled enzyme assays are described for measuring inorganic phosphates, organic phosphates and phosphate-liberating enzymes in biological material. The assays all determine Pi by its reaction with inosine, catalysed by nucleoside phosphorylase; this yields ribose 1-phosphate and hypoxanthine. The hypoxanthine is oxidized to uric acid by xanthine oxidase, and may be measured either by the absorb...