Background-Data on the clinical presentation and genotype-phenotype correlation of patients with congenital long-QT syndrome (LQTS) diagnosed at perinatal through infantile period are limited. A nationwide survey was conducted to characterize how LQTS detected during those periods is different from that in childhood or adolescence. Methods and Results-Using questionnaires, 58 cases were registered from 33 institutions. Diagnosis (or suspicion) of LQTS was made during fetal life (nϭ18), the neonatal period (nϭ31, 18 of them at 0 to 2 days of life), and beyond the neonatal period (nϭ9). Clinical presentation of LQTS included sinus bradycardia (nϭ37), ventricular tachycardia/torsades de pointes (nϭ27), atrioventricular block (nϭ23), family history of LQTS (nϭ21), sudden cardiac death/aborted cardiac arrest (nϭ14), convulsion (nϭ5), syncope (nϭ5), and others. Genetic testing was available in 41 (71%) cases, and the genotype was confirmed in 29 (71%) cases, consisting of LQT1 (nϭ11), LQT2 (nϭ11), LQT3 (nϭ6), and LQT8 (nϭ1). Ventricular tachycardia/torsades de pointes and atrioventricular block were almost exclusively observed in patients with LQT2, LQT3, and LQT8, as well as in those with no known mutation. In LQT1 patients, clues to diagnosis were mostly sinus bradycardia or family history of LQTS. Sudden cardiac death/aborted cardiac arrest (nϭ14) was noted in 4 cases with no known mutations as well as in 4 genotyped cases, although the remaining 6 did not undergo genotyping. Their subsequent clinical course after aborted cardiac arrest was favorable with administration of -blockers and mexiletine and with pacemaker implantation/implantable cardioverter-defibrillator. Conclusions-Patients with LQTS who showed life-threatening arrhythmias at perinatal periods were mostly those with LQT2, LQT3, or no known mutations. Independent of the genotype, aggressive intervention resulted in effective suppression of arrhythmias, with only 7 deaths recorded. (Circ Arrhythm Electrophysiol. 2010;3:10-17.)
The novel organic ion-complex crystal composed of protonated merocyanine and p-toluenesulfonate anion, i.e., 1-methyl-4-(2-(4-hydroxyphenyl)vinyl)pyridinium 4-toluenesulfonate (MC-PTS), was synthesized for second-order nonlinear optics. Crystal structure analysis revealed that MC-PTS crystallized in the space group of P1, i.e., the most desired space group for waveguide applications where molecular dipoles are perfectly aligned in one direction. It was also pointed out that the tetrahedral sulfonate anion plays the role of a chiral handle to give noncentrosymmetric space groups.
Full-color recording is technologically important not only for the storage and reproduction of color information but also for the enhancement of recording density without a reduction in the size of one unit area by utilizing the spectrum of light for recording and reading memories, as in photochemical hole burning. Although full-color "writeonce" recording media (e.g., photographs and photocopiers) or rewritable "on-and-off" recording media (e.g., magnetic, opto-magnetic, and thermo-optic recordings) are well developed, rewritable full-color recording has still not been realized. This can be attributed mainly to the difficulty of finding thermally stable materials that change color reversibly under the action of external stimuli. Here we present a cholesteric low-molecular-weight compound that, in the form of a thin solid film, shows stable iridescent colors in the visible region. The color of the compound is totally, partially, or in an imagewise manner changed into selected colors by thermal treatment above 87°C. Compounds with this property should find applications as highdensity memory media that use the spectrum of light or as thermo-sensitive full-color recording materials.Cholesteric color has fascinated people since the discovery of liquid crystals.''] The ability to change the cholesteric colors over the whole visible region by stimuli such as temperature, pressure, and electric field is important from not only a scientific but also a practical point of view. On the other hand, fixing of specific colors, namely colors insensitive to stimuli, is also attracting much attention in connection with the iridescent colors of a jewel beetle''] and for applications such as optical filters for selective reflection or large optical rotation. Polymeric materials have already been used to obtain thermally insensitive solid films with cholesteric str~cture.[~-~] High viscosity or three-dimensional networks of polymer chains practically fixes the pitch of the helical configuration of polymers, which determines the colors of cholesteric liquid crystalline compounds, providing a thermally insensitive cholesteric color. Although it is also possible to tune the color, by changing the monomer ratio in copolymer^,[^'^] by changing the temperature during photopolymerization of cholesteric monom e r~, '~] or by changing the ratio between polymerizing solution and lyotropic reversible and fast switching of the cholesteric color, which is desired for applica-tions as rewritable memory or recording media, is impossible to achieve with these polymeric materials. A low-molecular-weight cholesteric compound that we recently synthesized shows, in the solid state, changeable iridescent colors that can be selected from the whole visible region by thermal treatment.The cholesteryl derivative 1 (Scheme 1) was synthesized by condensation of cholesterol and the corresponding diacid in the presence of dicyclohexyl carbodiimide and 4-dimethylamiriopyridine in dichloromethane. This compound, 0 Scheme 1. Chemical structure of cholesteryl deriv...
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