Bioluminescence of ()-Cypridina Luciferin with Luciferase.

Cypridina luciferin (CypL) is a marine natural product that functions as the luminous substrate for the enzyme luciferase (CypLase). CypL has two enantiomers, ()- and ()-CypL, due to its one chiral center at the -butyl moiety. Previous studies reported that ()-CypL or racemic CypL with CypLase produced light, but the luminescence of ()-CypL with CypLase has not been investigated.

Structural designing of ZnSiO:Mn nanocrystals by co-doping of alkali metal ions in mesoporous silica channels for enhanced emission efficiency with short decay time.

High purity ZnSiO:Mn crystals were synthesized by impregnating a precursor solution into mesoporous silica followed by sintering process. The effects of doping alkali metal ions (Li, Na, K) on the structural, morphological and photoluminescence properties were investigated. Formation of single phase α-ZnSiO:Mn crystals was confirmed from X-ray diffraction.

Human metaphase chromosome consists of randomly arranged chromatin fibres with up to 30-nm diameter.

During cell division, mitotic chromosomes assemble and are equally distributed into two new daughter cells. The chromosome organisation of the two chromatids is essential for even distribution of genetic materials. Although the 11-nm fibre or nucleosome structure is well-understood as a fundamental fibrous structure of chromosomes, the reports on organisation of 30-nm basic chromatin fibres have been controversial, with debates on the contribution of 30-nm or thicker fibres to the higher order inner structure of chromosomes.

Development and efficacy of a clinician-targeted refresher course for treating nonpneumonia respiratory tract infections.

Background: In 2017, the Japanese government published an evidence-based manual describing the appropriate use of antibiotics in outpatient settings to tackle the problem of antimicrobial resistance. To fill the evidence-practice gap, we developed a clinician-targeted course aimed at improving clinician skills in the daily clinical practice of treating acute respiratory tract infections (RTIs) based on the manual. The aim of this study was to evaluate the efficacy of the course.

Topological Control of Columnar Stacking Made of Liquid-Crystalline Thiophene-Fused Metallonaphthalocyanines.

The spontaneous organization of two-dimensional polyaromatic molecules into well-defined nanostructures through noncovalent interactions is important in the development of organic-based electronic and optoelectronic devices. Two regioisomers of thiophene-fused zinc naphthalocyanines ZnTNcendo and ZnTNcexo have been designed and synthesized to obtain photo- and electroactive liquid crystalline materials. Both compounds exhibited liquid crystalline behavior over a wide temperature range through intermolecular π-π interactions and local phase segregation between the aromatic cores and peripheral side chains.

Photo Induced Membrane Separation for Water Purification and Desalination Using Azobenzene Modified Anodized Alumina Membranes.

Water purification and desalination to produce end-use water are important agendas in 21st century, because the global water shortage is becoming increasingly serious. Those processes using light energy, especially solar energy, without the consumption of fossil fuels are desired for creating sustainable society. For these earth-friendly water treatments, nanoporous materials and membranes are expected to provide new technologies.

Temperature control of light transmission using mixed system of silica hollow particles with nanoparticle shell and organic components.

We reported before that a silica hollow particle whose shell consists of silica nanoparticle (SHP-NP) has a high light reflection ability to prevent light transmission through the particle, which is caused from the intensive light diffusion by the hollow structure and the nanoparticle of the shell. Since the difference in the refractive indices between silica and air is responsible for the strong light reflection, the mixing of the particle with organic components having refractive indices close to that of silica such as tetradecane produced transparent mixtures by suppression of the light reflection. The transparency of the mixtures thus prepared could be controlled by temperature variation.

Speed of mental addition in an abacus expert, estimated by eye movements and neural activities.

A grand expert of abacus looked at a display on which three-digit numbers were aligned vertically with constant spacing, for sequentially adding the numbers mentally. His eye regularly moved downward by alternating a fixation to one of the numbers with a saccade to another below it, with the average period of the alternations at 271 msec. His magnetoencephalogram averaged with respect to start of the fixations revealed activity in the right superior parietal cortex.

Preparation of hierarchical architectures of silica particles with hollow structure and nanoparticle shells: a material for the high reflectivity of UV and visible light.

Silica microcapsules (silica hollow particles) are readily prepared by a single step of the interfacial reaction method, where a W/O/W emulsion is employed effectively. This is a simple (one-step process), inexpensive approach (silica source is sodium silicate) to producing hollow silicas. The addition of NaCl to the sodium silicate solution as the inner water phase of the W/O/W emulsion plainly influenced the shell structure of the silica hollow particles.

Proteomic characterization of the striatum and midbrain treated with 6-hydroxydopamine: alteration of 58-kDa glucose-regulated protein and C/EBP homologous protein.

The present study performed proteomic analysis of the midbrain and striatum of 6-hydroxydopamine (6-OHDA)-treated neonatal rats--a model of attention-deficit hyperactivity disorder (ADHD). Proteomic analysis revealed that a 58-kDa glucose-regulated protein (Grp58) was temporarily phosphorylated and its level was elevated by 6-OHDA. Furthermore, 6-OHDA increased the expression level of C/EBP homologous protein (CHOP), a mediator of endoplasmic reticulum (ER) stress response, in the midbrain and striatum.

Photoinduced acceleration of the effluent rate of developing solvents in azobenzene-tethered silica gel.

The switching of a molecular length of azobenzene between its trans and cis forms by photoirradiation originates various photoresponsive systems in the molecular level and/or nanolevel. Recently, we and another group separately reported that some azobenzene-modified mesoporous silicas remarkably promote the release of molecules from the inside of the mesopore to the outside, when the lights, both UV and visible lights, were irradiated simultaneously. In these cases, the release rates of molecules were enhanced by the impeller-like effect of molecular motion of azobenzene moiety attributed to the continuous photoisomerization between the trans and cis isomers.

Blue-emitting small silica particles incorporating ZnSe-based nanocrystals prepared by reverse micelle method.

ZnSe-based nanocrystals (ca. 4-5 nm in diameter) emitting in blue region (ca. 445 nm) were incorporated in spherical small silica particles (20-40 nm in diameter) by a reverse micelle method.

Drastic enhancement of discotic mesomorphism induced by fluorination of the peripheral phenyl groups in triphenylene mesogens.

Four derivatives of hexakis(4-alkoxybenzoyloxy)triphenylene, for which peripheral phenylene groups are fluorinated at the inner and the outer positions were studied for their mesomorphic behaviour to reveal that the alteration of fluorinated positions in the phenyl rings leads to a drastic change of the mesomorphism involving the thermal stability.

Molecular mechanisms of 6-hydroxydopamine-induced cytotoxicity in PC12 cells: involvement of hydrogen peroxide-dependent and -independent action.

The neurotoxin 6-hydroxydopamine (6-OHDA) has been widely used to generate an experimental model of Parkinson's disease. It has been reported that reactive oxygen species (ROS), such as the superoxide anion and hydrogen peroxide (H2O2), generated from 6-OHDA are involved in its cytotoxicity; however, the contribution and role of ROS in 6-OHDA-induced cell death have not been fully elucidated. In the present study using PC12 cells, we observed the generation of 50 microM H2O2 from a lethal concentration of 100 microM 6-OHDA within a few minutes, and compared the sole effect of H2O2 with 6-OHDA.

Silica hollow spheres with nano-macroholes like diatomaceous earth.

Artificial synthesis of hollow cell walls of diatoms is an ultimate target of nanomaterial science. The addition of some water-soluble polymers such as sodium polymethacrylate to a solution of water/oil/water emulsion system, which is an essential step of the simple synthetic procedure of silica hollow spheres (microcapsules), led to the formation of silica hollow spheres with nano-macroholes (>100 nm) in their shell walls, the morphologies of which are analogous to those of diatom earth.

Direct encapsulation of BSA and DNA into silica microcapsules (hollow spheres).

We reported before that silica hollow spheres (microcapsules) are prepared by interfacial reaction method that W/O emulsion with the aqueous solution of sodium silicate and n-hexane solution of Tween 80 and Span 80 is combined with another aqueous solution of silica precipitant such as NH(4)HCO(3) and NH(4)Cl. This procedure using W/O/W emulsion fabricates the hollow structures of silica particles directly, and additional steps such as the removal of core parts, that are often essential for the preparation of hollow particles via core-shell materials, are not required. When biomacromolecules such as protein and nucleic acid are mixed in the aqueous solution of sodium silicate, these macromolecules can be encapsulated into the microcapsules.

Switching catalytic reaction conducted in pore void of mesoporous material by redox gate control.

A molecular gate attached on the pore outlet of a mesoporous material, which is opened and closed by redox system of thiol groups, effectively switched the progress of a catalytic reaction promoted by the acidic site in the pore void.

Adsorption of duplex DNA on mesoporous silicas: possibility of inclusion of DNA into their mesopores.

It is well known that a silica surface cannot adsorb duplex DNA in common aqueous solution (not chaotropic solution) because of the electrostatic repulsion of the silica surface and polyanionic DNA. However, we recently found that when duplex DNA in phosphoric acid form (or in acidic solution) was used, DNA was successfully adsorbed into mesoporous silicas even in low-salt aqueous solution. The adsorption behaviors of DNA into mesoporous silicas were influenced by the pore diameter sizes.

Synthesis of organic-inorganic hybrid mesoporous tin oxophosphate in the presence of anionic surfactant.

Synthesis of novel mesoporous hybrid tin oxophosphate is reported from phenylphosphonic acid as the only precursor of phosphorus in the presence of anionic surfactant (SDS), which possesses a wormhole mesoporous structure and is stable even after calcination at 550 degrees C.

Quantum effect on the internal proton transfer and structural fluctuation in the H+ 5 cluster.

The thermal equilibrium state of H+(5) is investigated by means of an ab initio path integral molecular dynamics (PIMD) method, in which degrees of freedom of both nuclei and electrons at finite temperature are quantized within the adiabatic approximation. The second-order Moller-Plesset force field has been employed for the present ab initio PIMD. At 5-200 K, H+(5) is shown to have the structure that the proton is surrounded by the two H(2) units without any exchange of an atom between the central proton and the H(2) unit.

Interconversion behavior of the C-H bond in the CH4+ radical cation: ab initio molecular dynamics study.

Thermal motion of CH4+ is investigated by performing an ab initio molecular dynamics method with the second-order Møller-Plesset (MP2)/6-311G** force field. In the trajectories obtained at 400 K, we have observed rapid interconversion behavior of the geometrical parameters of CH4+ with the frequency of 0.6/ps, where the C-H pair forming the small angle around 55 degrees is switched to another pair on subpicosecond time scale.

A sol-gel method using acetic anhydride in the presence of cholesterol in organic solution media: preparation of silicas that recognize steroid hormones.

Silicas were prepared by a sol-gel method from tetraethoxysilane and acetic anhydride in the presence of cholesterol in organic solution media. Some silicas had higher pore volumes than silicas obtained in the absence of cholesterol. The adsorption abilities by these silicas were compared using various compounds in benzene solution.

Photocontrolled reversible release of guest molecules from coumarin-modified mesoporous silica.

Since the discovery of MCM-41 more than ten years ago, many investigations have explored the suitability of hexagonal mesoporous silicas for potential practical applications. These range from catalysis and optically active materials to polymerization science, separation technology and drug delivery, with recent successes in the fabrication of hybrid mesoporous organosilicas expected to open up further application possibilities. Because the pore voids of this class of materials exhibit relatively narrow pore size distributions in the range of 2-4 nm in diameter, mesoporous silicas can selectively include organic compounds and release them continuously at a later stage.