Preparation of Porous Glass-Ceramics with a Skeleton of NASICON-Type Crystal CuTi2(PO4)3

A novel porous glass-ceramic with a skeleton of CuTi₂(PO₄)₃ was prepared by controlled crystallization of a glass and subsequent chemical leaching of the resulting dense glass-ceramic. A volume-crystallized dense glass-ceramic composed of CuTi₂(PO₄)₃ and Cu₃(PO₄)₂ whose surface was covered by a CuO thin layer was prepared by reheating a glass with a nominal composition of 50CuO·20TiO₂30P₂O₅ (in mol%) glass in air. When the resultant glass-ceramic was leached with dilute H₂SO₄, Cu₃(PO₄)₂ and CuO phases were dissolved out selectively, leaving a crystalline CuTi₂(PO₄)₃ skeleton. The specific surface area and the average pore radius of the porous glass-ceramic obtained were approximately 45 m₂g_-1 and 9 nm, respectively. The porous glass-ceramic showed catalytic activity in the conversion reaction of propene into acrolein.     

Mechanism‐Based Inhibitor of DNA Cytosine‐5 Methyltransferase by a SNAr Reaction with an Oligodeoxyribonucleotide Containing a 2‐Amino‐4‐Halopyridine‐C‐Nucleoside

In chromatin, 5‐methylcytosine (mC), which represents the fifth nucleobase in genomic DNA, plays a role as an inducer of epigenetic changes. Tumor cells exhibit aberrant DNA methylation patterns, and inhibition of human DNA cytosine‐5 methyltransferase (DNMT), which is responsible for generating mC in CpG sequences, is an effective strategy to treat various cancers. Here, we describe the design, synthesis, and evaluation of the properties of 2‐amino‐4‐halopyridine‐C‐nucleosides (d^XP) and oligodeoxyribonucleotides (ODNs) containing d^XP as a novel mechanism‐based inhibitor of DNMTs. The designed ODN containing ^XPpG forms a complex with DNMTs by covalent bonding through a nucleophilic aromatic substitution (S_NAr) reaction, and its cell proliferation activity is investigated. This study suggests that d^XP in a CpG sequence of DNA could serve as a potential nucleic acid drug lead in cancer chemotherapy and a useful chemical probe for studies of epigenetics. Our molecular design using a S_NAr reaction would be useful for DNMTs and other protein–DNA interactions.     

Induction of Heat Shock Protein 70 Ameliorates Ultraviolet-Induced Photokeratitis in Mice

Acute ultraviolet (UV) B exposure causes photokeratitis and induces apoptosis in corneal cells. Geranylgeranylacetone (GGA) is an acyclic polyisoprenoid that induces expression of heat shock protein (HSP)70, a soluble intracellular chaperone protein expressed in various tissues, protecting cells against stress conditions. We examined whether induction of HSP70 has therapeutic effects on UV-photokeratitis in mice. C57 BL/6 mice were divided into four groups, GGA-treated (500 mg/kg/mouse) and UVB-exposed (400 mJ/cm²), GGA-untreated UVB-exposed (400 mJ/cm²), GGA-treated (500 mg/kg/mouse) but not exposed and naive controls. Eyeballs were collected 24 h after irradiation, and corneas were stained with hematoxylin and eosin (H&E) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL). HSP70, reactive oxygen species (ROS) production, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and protein kinase B (Akt) expression were also evaluated. Irradiated corneal epithelium was significantly thicker in the eyes of mice treated with GGA compared with those given the vehicle alone (p < 0.01). Significantly fewer TUNEL-positive cells were observed in the eyes of GGA-treated mice than controls after irradiation (p < 0.01). Corneal HSP70 levels were significantly elevated in corneas of mice treated with GGA (p < 0.05). ROS signal was not affected by GGA. NF-κB activation was reduced but phospho-(Ser/Ther) Akt substrate expression was increased in corneas after irradiation when treated with GGA. GGA-treatment induced HSP70 expression and ameliorated UV-induced corneal damage through the reduced NF-κB activation and possibly increased Akt phosphorilation.     

Comparative Analysis of Serum microRNA in Diagnosed Ocular Sarcoidosis versus Idiopathic Uveitis with Ocular Manifestations of Sarcoidosis

“Idiopathic” is the most common category of uveitis, representing cases in which a specific diagnosis has not been established despite work-up. Sarcoidosis is a systemic granulomatous disorder affecting multiple organs including the lungs, skin, kidneys, and eyes. We used microRNA (miRNA) microarrays to investigate serum miRNA profiles of patients with ocular sarcoidosis as diagnosed by specific criteria (diagnosed ocular sarcoidosis), and patients with idiopathic uveitis characterized by ocular manifestations of sarcoidosis (suspected ocular sarcoidosis). Principal component analysis (PCA) and hierarchical clustering showed that serum miRNA profiles of diagnosed ocular sarcoidosis and suspected ocular sarcoidosis were both clearly distinguishable from healthy controls. Furthermore, comparative analysis of the miRNA profiles showed highly similar patterns between diagnosed ocular sarcoidosis and suspected ocular sarcoidosis. Pathway analysis revealed common pathways were involved in the two groups, including those of WNT signaling and TGF-beta signaling. Our study demonstrated a high overlap of differentially expressed serum miRNAs in patients with diagnosed ocular sarcoidosis and suspected ocular sarcoidosis, suggesting that these groups share a similar underlying pathology and may represent possible variants of the disease. Characterization of serum miRNA profiles may provide an opportunity for earlier diagnosis and treatment, and may inform more accurate clinical prognosis in patients with an ocular sarcoidosis phenotype.     

Preparation of diblock copolymer based on poly(4-n-butyltriphenylamine) via palladium coupling polymerization

A self-condensing monomer 4-(4′-bromophenyl)-4″-n-butyldiphenylamine (1) was synthesized, and successfully converted to poly(4-n-butyltriphenylamine) (PBTPA) by arylamination using palladium catalyst. PBTPAs can be functionalized at both terminals separately by adding an aryl bromide or arylamine derivatives as a terminator, which enabled us to prepare the diblock copolymer PBTPA-block-PEO. Polymer characterization was performed by ¹H NMR, ¹³C NMR, and DSC, which confirmed that the PEO segment was successfully introduced at the terminal of PBTPA. The surface morphology in a thin film of PBTPA-block-PEO was examined by AFM, revealing that a microphase-separated structure or cup-shaped structure with PEO sphere domains formed when the film was spin-cast from 1,1,2,2-tetrachloroethane solutions of different concentrations.     

Synthesis and luminescent properties of block copolymers based on polyfluorene and polytriphenylamine

For the preparation of block copolymers containing polyfluorene (PF) and hole transporting segment, PF homopolymers with diphenylamine terminals were synthesized by Suzuki coupling polymerization. The terminals of PF were converted to polytriphenylamine (PTPA) block by C–N coupling polymerization to give PTPA-block-PF-block-PTPA (PF-PTPA) triblock copolymers with different PTPA chain lengths. These polymers were soluble in common organic solvents and readily formed thin films by solution processing. All of the polymers exhibited similar UV absorption and PL emission properties both in chloroform solution and in film state. PF-PTPA block copolymers showed relatively high HOMO compared with that of PF by cyclic voltammetry. Compared with corresponding PF homopolymers, the EL devices based on PF-PTPA block copolymers showed higher luminance and current efficiency than those of PF homopolymers because of the improvement of hole injection by the introduction of PTPA segment.     

Data analysis on solar irradiance and performance characteristics of solar modules with a test facility of various tilted angles and directions

We examined and evaluated the output characteristics and the deterioration lowering factors of modules installed under various conditions (module directions and tilted angles) based on the data collected at the multi-position test facility, which was produced and installed in order to conduct evaluation using design parameters (correction coefficient). This report introduces example data and the results of our evaluation.     

Compact sensor for measuring two-dimensional tilt using a two-dimensional transmission grating and the Talbot effect

This paper proposes a tilt sensor that measures the small two-dimensional tilt of a plane reflective object using the Talbot effect. It is an extension of a previously proposed one-dimensional tilt sensor. The light beam reflected from the object impinges on a hexagonal grating, and the intensity of the diffracted wave is detected on an image sensor located at a Talbot distance from the grating. The diffraction intensity displaces due to the tilt of the object. The displacement is calculated by the Fourier transform method to obtain the two-dimensional tilt. This sensor is very simple and compact. The principle of the sensor is explained for a grating with a general pattern. An experiment using a hexagonal grating shows its validity. Discussions are given for making it more practical.     

Terahertz Imaging System for Medical Applications and Related High Efficiency Terahertz Devices

A terahertz (THz) imaging system and high efficient terahertz sources and detectors for medical applications were developed. A fiber laser based compact time domain terahertz tomography system was developed with a high depth resolution of less than 20 μm. Three-dimensional images of porcine skin were obtained including some physical properties such as applied skin creams. The discrimination between healthy human tissue and tumor tissue has been achieved using reflection spectra. To improve the THz imaging system, a ridge waveguide LiNbO₃ based nonlinear terahertz generator was studied to achieve high output power. A ridge waveguide with 5-7 μm width was designed for high efficiency emission from the LiNbO₃ crystal by the electro-optic Cherenkov effect. Terahertz electronic sources and detectors were also realized for future imaging systems. As electronic source devices, resonant tunneling diode (RTD) oscillators with a patch antenna were fabricated using an InGaAs/InAlAs/AlAs triple barrier structure. On the other side, Schottky barrier diode (SBD) detectors with a log-periodic antenna were fabricated by thin-film technology on a Si substrate. Both devices operate above 1 THz at room temperature. This electronic THz device set could provide a future high performance imaging system.