Lie algebra contractions on two-dimensional hyperboloid

Abstract

Brugada syndrome has been linked to mutations in SCN5A. Agents that dissociate slowly from the sodium channel such as flecainide and ajmaline unmask the Brugada syndrome electrocardiogram and precipitate ventricular tachycardia/fibrillation. Lidocaine, an agent with rapid dissociation kinetics, has previously been shown to exert no effect in patients with Brugada syndrome. We characterized a novel double mutation of SCN5A (V232I in DI-S4+L1308F in DIII-S4) identified in a rare case of lidocaine (1 mg/kg)-induced Brugada syndrome. We studied lidocaine blockade of INa generated by wild-type and V232I+L1308F mutant cardiac sodium channels expressed in mammalian TSA201 cells using patch clamp techniques. Despite no significant difference in steady-state gating parameters between V232I+L1308F and wild-type sodium currents at baseline, use-dependent inhibition of INa by lidocaine was more pronounced in V232I+L1308F versus wild-type (73.0±0.1% versus 18.23±0.04% at 10 ?mol/L measured at 10 Hz, respectively). A dose of 10 ?mol/L lidocaine also caused a more negative shift of steady-state inactivation in V232I+L1308F versus wild-type (-14.1±0.3 mV and -4.8±0.3 mV, respectively). The individual mutations produced a much less accentuated effect. We report the first case of lidocaine-induced Brugada electrocardiogram phenotype. The double mutation in SCN5A, V232I, and L1308F alters the affinity of the cardiac sodium channel for lidocaine such that the drug assumes Class IC characteristics with potent use-dependent block of the sodium channel. Our results demonstrate an additive effect of the 2 missense mutations to sensitize the sodium channel to lidocaine. These findings suggest caution when treating patients carrying such genetic variations with Class I antiarrhythmic drugs. " 2008 American Heart Association, Inc.",,,,,,"10.1161/CIRCRESAHA.108.172619",,,"http://hdl.handle.net/20.500.12104/42550","http://www.scopus.com/inward/record.url?eid=2-s2.0-50949092654&partnerID=40&md5=44df12f00203be4d16925ea516e0938c",,,,,,"4",,"Circulation Research",,"396

404",,"103",,"Scopus

WOS",,,,,,"Arrhythmia (mechanisms); Brugada syndrome; Ion channels; Na channels; Sudden death",,,,,,"Lidocaine-induced brugada syndrome phenotype linked to a novel double mutation in the cardiac sodium channel",,"Article" "38282","123456789/35008",,"Villalvazo Naranjo, Juan Universidad de Guadalajara",,"Villalvazo Naranjo, Juan Universidad de Guadalajara",,"1994",,,,,,,,,,"0185-0849","http://hdl.handle.net/20.500.12104/36503",,,"Español",,,,"232",,"Economía informa",,"14-19",,,,"CLASE",,,,,,,,"Empresas",,,,"Las incubadoras de empresas y los mecanismos de vinculación. El caso de la Universidad de Guadalajara",,"journalArticle" "44330","123456789/35008",,"Senashov, S.I., Siberian State Aerospace University, Krasnoyarskiy Rabochiy Avenue 31, Krasnoyarsk, Russian Federation; Yakhno, A., University of Guadalajara, Department of Mathematics, Blvd. García Barragan 1451, 44430 Guadalajara, Mexico; Yakhno, L., University of Guadalajara, Department of Mathematics, Blvd. García Barragan 1451, 44430 Guadalajara, Mexico",,"Senashov, S.I.

Yakhno, A.

Yakhno, L.",,"2007",,"The framework of generalized (Lie-Backlund) symmetries is used to analyze a general homogeneous hyperbolic system of bi-dimensional quasilinear equations. The symmetries of the first order are constructed and the theorem of the existence of the generalized symmetries is formulated. As example, we consider the spatially one-dimensional time dependent system of equations, which describes the gravity-driven free surface flow of granular avalanches.",,,,,,,,,"http://hdl.handle.net/20.500.12104/42551","http://www.scopus.com/inward/record.url?eid=2-s2.0-33751580306&partnerID=40&md5=07ada945294d1fca2ebbaaaf7e3fae5b",,,,,,"1",,"WSEAS Transactions on Mathematics",,"16

21",,"6",,"Scopus",,,,,,"Generalized symmetries; Highest symmetries; Lie - Backlund transformations; Partial differential equations",,,,,,"Lie - Backlund symmetries of homogeneous system of bi-dimensional equations",,"Article" "38283","123456789/35008",,,"Sánchez Ruiz, Enrique E.",,"2000",,,,,,,,,,"0187-8190",,"http://hdl.handle.net/20.500.12104/36504",,"Español",,,,"64",,"Revista mexicana de comunicación",,"40-43",,"12",,"CLASE",,,,,,,,"Medios de comunicación masiva",,"Las industrias culturales latinoamericanas en tiempo de la globalización. Polarización entre países pobres y ricos",,,,"journalArticle", "44331","123456789/35008",,"Pogosyan, G.S., Departamento de Matematicas, CUCEI, Universidad de Guadalajara, Jalisco, Mexico, Joint Institute for Nuclear Research, Dubna, Russian Federation, Physics Department, Yerevan State University, Yerevan, Armenia; Yakhno, A., Departamento de Matematicas, CUCEI, Universidad de Guadalajara, Jalisco, Mexico",,"Pogosyan, G.S.

Yakhno, A.",,"2010",,"The Inönü-Wigner contraction from the SO(2, 1) group to the Euclidean E(2) and E(1, 1) group is used to relate the separation of variables in Laplace-Beltrami (Helmholtz) equations for the four corresponding two-dimensional homogeneous spaces: two-dimensional hyperboloids and two-dimensional Euclidean and pseudo-Euclidean spaces. We show how the nine systems of coordinates on the two-dimensional hyperboloids contracted to the four systems of coordinates on E2 and eight on E1,1. The text was submitted by the authors in English. " 2010 Pleiades Publishing, Ltd.