Post-transcriptional downregulation of sarcolipin mRNA by triiodothyronine in the atrial myocardium.

Thyroid hormone-mediated positive cardiotropic effects are differently regulated between the atria and ventricles. This regulation is, at least in part, dependent on sarcoplasmic reticulum (SR) proteins. Sarcolipin, a homologue of phospholamban, has been recently identified as an atrium-specific SR protein. The expression of sarcolipin mRNA was significantly decreased in the atria of mice with hyperthyroidism and in 3,5,3'-triiodo-l-thyronine-treated neonatal rat atrial myocytes. Promoter activity and mRNA stability analyses revealed that thyroid hormone post-transcriptionally down regulated the expression of sarcolipin mRNA. The atrium-specific effect of thyroid hormone may occur in part through the regulation of atrial sarcolipin gene expression.

Peracetic acid-ionic liquid pretreatment to enhance enzymatic saccharification of lignocellulosic biomass.

To enhance enzymatic saccharification of pine biomass, the pretreatment reagents peracetic acid (PAA) and ionic liquid (IL) were validated in single reagent pretreatments or combination pretreatments with different sequences. In a 1h saccharification, 5-25% cellulose conversion was obtained from the single pretreatment of PAA or IL. In contrast, a marked enhancement in conversion rates was achieved by PAA-IL combination pretreatments (45-70%). The PAA followed by IL (PAA+IL) pretreatment sequence was the most effective for preparing an enzymatic digestible regenerated biomass with 250-fold higher glucose formation rates than untreated biomass and 2- to 12-fold higher than single pretreatments with PAA or IL alone. Structural analysis confirmed that this pretreatment resulted in biomass with highly porous structural fibers associated with the reduction of lignin content and acetyl groups. Using the PAA+IL sequence, biomass loading in the pretreatment step can be increased from 5% to 15% without significant decrease in cellulose conversion.

Multiple transcripts of Ca2+ channel alpha1-subunits and a novel spliced variant of the alpha1C-subunit in rat ductus arteriosus.

Voltage-dependent Ca(2+) channels (VDCCs), which consist of multiple subtypes, regulate vascular tone in developing arterial smooth muscle, including the ductus arteriosus (DA). First, we examined the expression of VDCC subunits in the Wistar rat DA during development. Among alpha(1)-subunits, alpha(1C) and alpha(1G) were the most predominant isoforms. Maternal administration of vitamin A significantly increased alpha(1C)- and alpha(1G)-transcripts. Second, we examined the effect of VDCC subunits on proliferation of DA smooth muscle cells. We found that 1 microM nitrendipine (an L-type Ca(2+) channel blocker) and kurtoxin (a T-type Ca(2+) channel blocker) significantly decreased [(3)H]thymidine incorporation and that 3 microM efonidipine (an L- and T-type Ca(2+) channel blocker) further decreased [(3)H]thymidine incorporation, suggesting that L- and T-type Ca(2+) channels are involved in smooth muscle cell proliferation in the DA. Third, we found that a novel alternatively spliced variant of the alpha(1C)-isoform was highly expressed in the neointimal cushion of the DA, where proliferating and migrating smooth muscle cells are abundant. The basic channel properties of the spliced variant did not differ from those of the conventional alpha(1C)-subunit. We conclude that multiple VDCC subunits were identified in the DA, and, in particular, alpha(1C)- and alpha(1G)-subunits were predominant in the DA. A novel spliced variant of the alpha(1C)-subunit gene may play a distinct role in neointimal cushion formation in the DA.

Simultaneous stratospheric gas and aerosol retrievals from broadband infrared occultation measurements.

The inversion method for simultaneous gas (O3, NO2, HNO3, N2O, CH4, H2O, CFC-11, CFC-12, N2O5, and ClONO2) and aerosol retrievals from broadband continuous IR spectra of occultation measurements is described. Both gas and aerosol physical modeling with consideration of the multicomponent character of aerosol and polar stratospheric clouds (PSCs) are used to minimize the difference between measured and modeled transmittance spectra under smoothness constraints imposed on particle-size distributions for each PSC component and positive constraints on all gas and aerosol parameters. The method is tested by numerical simulations in which synthetic occultation measurements inherent to the improved limb atmospheric spectrometer are used. The study reveals that the method has significant advantages over other approaches based on offset or gas-window-channel aerosol correction for accurate gas retrievals and provides additional information on the particle-size composition, volume density, and chemical component character of PSCs.

Retrieval of trace gases from aerosol-influenced infrared transmission spectra observed by low-spectral-resolution Fourier-transform spectrometers.

A method for the simultaneous retrieval of gas concentrations and an extinction spectrum of aerosols and polar stratospheric clouds from infrared transmission spectra observed in the solar occultation geometry is described. It is particularly suited to measurements by Fourier-transform spectrometers with relatively low spectral resolution (0.1-1 cm(-1)). The method does not require a priori assumptions on aerosol properties; it utilizes only the fact that the wave-number dependence of aerosol extinction is much weaker than that of gas absorption. In this method, an aerosol extinction spectrum is approximated by a straight line within a relatively wide spectral range defined as mediumwindow.

Restrictive cardiomyopathy with right-sided dominant heart failure after sinus conversion from atrial fibrillation: case report.

A 44-year-old woman with restrictive cardiomyopathy showed right-sided dominant heart failure after conversion to sinus rhythm from paroxysmal atrial fibrillation (AF). During cardiac catheterization, the hemodynamics were compared before and after cardioversion; that is, with AF and with sinus rhythm. The hemodynamic parameters worsened after conversion to sinus rhythm, with a significant decrease in heart rate, but improved with atrial pacing. Pacemaker implantation was performed to avoid bradycardia while keeping the sinus rhythm with amiodarone. As a result, the patient has been free from symptoms of heart failure for almost 1 year and her serum brain natriuretic peptide level also improved remarkably.