Cherry blossom flowers are familiar to the Japanese, and some species of the flowers soaked in salty vinegar are used as processed foods. The constituents of aqueous ethanol extract from cherry blossom (Prunus lannesiana) flowers (CBE) were examined and cinnamoyl and flavonol glucosides were isolated. To elucidate the pharmacological functions of CBE and its constituents, their effects on the production of advanced glycation end products (AGEs) and on AGE-induced fibroblast damage were examined. CBE and 1-O-(E)-caffeoyl-β-D-glucopyranoside (CaG), a principal compound in CBE, significantly suppressed the production of AGEs derived from glucose and albumin at 100 μg/mL. Among the flavonol glucosides, quercetin 3-O-β-D-glucopyranoside (QG) exhibited potent suppressive activity (IC50 : 30 μg/mL). CBE and CaG suppressed glyoxal-induced AGE production in fibroblasts at 10 μg/mL, but QG did not. In addition, CBE and CaG recovered collagen lattice formation consisting of collagen and glycated fibroblasts at 10 μg/mL. Moreover, CBE and its constituents, except kaempferol 3-O-(6″-malony)-β-D-glucopyranoside, significantly suppressed fibroblast apoptosis induced by carboxymethyl lysine-collagen at 10 μg/mL. These results show that cinnamoyl and flavonol glucosides of cherry blossom flowers suppress AGE production and AGE-induced fibroblast apoptosis. Cherry blossom flowers may be effective against skin AGE production and fibroblast damage by AGEs.

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A new two-dimensional electron gas (2DEG) field-effect transistor (FET) which operates in an MOS transistor-like mode is fabricated on undoped AlGaAs–GaAs heterostructures grown by both molecular beam epitaxy and organometallic vapour phase epitaxy. This device with very simple structure is expected to have performance comparable to those of selectively doped heterostructure FETs and can easily be integrated.

The influence of N2O gas addition on the properties of zinc oxide (ZnO) films grown on a-plane (11–20) sapphire (a-Al2O3) substrates was investigated, using a chemical vapor deposition method based on the reaction between dimethylzinc and high-temperature H2O produced by a catalytic H2-O2 reaction on platinum (Pt) nanoparticles. The addition of N2O was found to increase the size of the crystalline facets and to improve the crystal orientation along the c-axis. The electron mobility at 290 K was also increased to 234 cm2/Vs following the addition of N2O gas at a pressure of 3.2 × 10−3 Pa. In addition, the minimum full width at half maximum of the most intense photoluminescence peak derived from neutral donor bound excitons at 10 K decreased to 0.6 meV by the addition of N2O gas at a pressure of 3.1 × 10−2 Pa.