Adult onset cardiac dilatation in a transgenic mouse line with Galβ1,3GalNAc α2,3-sialyltransferase II (ST3Gal-II) transgenes: a new model for dilated cardiomyopathy

Sugar chain abnormalities in glycolipids and glycoproteins are associated with various diseases. Here, we report an adult onset cardiac dilatation in a transgenic mouse line with Galβ1,3GalNAc α2,3-sialyltransferase II (ST3Gal-II) transgenes. The transgenic hearts at the end-stage, at around 7 months old, were enlarged, with enlarged cavities and thin, low-tensile walls, typical of dilated cardiomyopathy. Although no apparent change was found in heart gangliosides, glycosylation of heart proteins was altered. Interestingly, sugar moieties not directly related to the ST3Gal-II catalytic reaction were also changed. Significant increases in calreticulin and calnexin were observed in hearts of the transgenic mice. These results suggest that expression of ST3Gal-II transgenes induces abnormal protein glycosylation, which disorganizes the endoplasmic/sarcoplasmic reticulum quality control system and elevates the calreticulin/calnexin level, resulting in suppression of cardiac function. The transgenic mice showed 100% incidence of adult onset cardiac dilatation, suggesting great potential as a new model for dilated cardiomyopathy.     

Purity for Hodge-Tate representations

We prove that a kind of purity holds for Hodge-Tate representations of the fundamental group of the generic fiber of a semi-stable scheme over a complete discrete valuation ring of mixed characteristic with perfect residue field. As an application, we see that the relative p-adic étale cohomology with proper support of a scheme separated of finite type over the generic fiber is Hodge-Tate if it is locally constant.     

Distribution and metabolism of selenohomolanthionine labeled with a stable isotope

The distribution and metabolism of selenohomolanthionine (4,4′-selenobis[2-aminobutanoic acid], SeHLan), a newly identified selenoamino acid in selenized Japanese pungent radish, were evaluated by administering ⁷⁷Se-labeled SeHLan at a dose of 25 μg/kg body weight in rats. Exogenous ⁷⁷Se of SeHLan was preferably distributed to the kidneys and remained in the intact form for up to 6 h after dosing. The accumulation in the kidneys is one of the specific characteristics of SeHLan, differing from other selenoamino acids, such as selenomethionine and Se-methylselenocysteine, which preferably accumulate in the pancreas. The intact form of SeHLan was detected in the serum and kidney supernatant but not in the urine, suggesting that the amount of exogenous Se that was distributed to the kidneys was within metabolic capacity. Indeed, the exogenous Se was converted into two urinary metabolites, Se-methylseleno-N-acetyl-galactosamine and trimethylselenonium. Exogenous Se was also detected in several selenoproteins, including selenoprotein P and extracellular glutathione peroxidase. SeHLan is expected to be a potential supplemental source of Se because its distribution differs from that of selenomethionine and Se-methylselenocysteine.     

Multilayered ordering of the metal nanoparticles in polymer thin films under photoirradiation

Interference light-induced photogeneration of metal nanoparticle in polymer films was explored. The nanoparticle was obtained from metal complex homogeneously dispersed in the film. Standing waves resulting from light interference were generated by irradiating nearly monochromatic light to the sample placed on a reflective substrate. During irradiation metal nanoparticles were developed by photoreduction of the metal complexes forming layers rich with particles. These nanoparticle-enriched layers were found to align in parallel to the reflective substrate, and they were separated from each other by a constant spacing. This layer spacing was varied by changing the wavelength and/or the incident angle of the irradiating light. The observed results show that the spatial distribution of the nanoparticles is determined by the optical interference within the film. Surprisingly, regions exist between the nanoparticle-enriched layers where the metal species are not detected. Such regions extends for distances larger than tens of nanometers. This means that the metal complexes initially homogeneously dispersed within the polymer were transported away from certain regions upon photoirradiation. The metal precursors are preferentially photoreduced into the metal nanoparticles at the constructive interference regions. The spatially varying consumption rates of the precursors are considered to lead a concentration gradient, thereby causing a directional diffusion of the unreduced precursors toward the regions where constructive interference occurs.     

High-energy diode-pumped picosecond regenerative amplification at 999 nm in wavelength with a cryogenically cooled Yb:LuLiF(4) crystal

A diode-pumped, cryogenically cooled Yb:LuLiF(4) regenerative amplifier has been developed for the first time to our knowledge. A chirped-seed pulse was amplified and compressed in the regenerative amplifier, simultaneously, which generated approximately 6 mJ, 13 ps pulses at 999 nm in wavelength without a pulse compressor. Simultaneous lasing at 999 and 1024 nm, respectively, was demonstrated, which could be used for different frequency generation in the terahertz region.     

Application of FDTD Method to the Analysis and Design of Leaky-Wave Antennas at Microwaves and Millimeter Waves

The Finite-Difference Time-Domain (FDTD) method, though rather heavy from the computational point of view, allows a complete characterization of a radiating structure, permitting also the accuracy evaluation of the other available solutions. Numerical results have been derived for a broad class of leaky-wave antennas proposed in the literature, always revealing a very good agreement with the methods previously employed. By the FDTD technique it is possible to easily determine the propagation and radiation characteristics of such structures, to obtain the radiation pattern in the far field, and to simulate the longitudinal tapering, necessary to satisfy the design requirements usually imposed to reduce sidelobes in the radiation diagram.     

Preparation of Polymer-Supported Chiral 1,2-Diamine as an Efficient Ligand for Asymmetric Hydrogenation Catalyst

An enantiopure 1,2-diamine having two phenolic hydroxy groups was synthesized, and attached to chloromethylated poly(styrene) through a benzyl ether linkage. The polymer-supported Ru precatalysts were prepared from the polymeric chiral 1,2-diamine and RuCl₂/BINAP complex. In the presence of t-BuOK the polymeric catalyst system worked well in asymmetric hydrogenation of aromatic ketones in a mixed solvent of 2-propanol and DMF. The insoluble polymeric catalyst was readily separated from the reaction mixture and reused at least several times without loss of the catalytic activity.