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Chemical derivatization into larger molecules has generated a monoclonal antibody that enables group-specific immunochemical detection of potent methamphetamine and amphetamine enantiomers.

Solar cells composed of silicon (Si) and polymer films have attracted much attention because of their high performance and facile preparation using aqueous solutions. Although a large amount of research has been carried out to further improve their performance, the factors required to achieve this are not yet fully understood from the perspective of physical chemistry. Here, we show the effect of additives on the performance of Si/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) solar cells using six different additives. The relationships among the solar cell performance, electrical properties, and the structure of the polymer film are examined by changing the additive and conducting cyclic voltammetry, electric conductivity, and two-dimensional grazing incidence angle X-ray diffraction measurements. The dipole moment of the additive molecule was determined to be a key factor for improving the performance of Si/PEDOT:PSS solar cells. In particular, an additive with a higher dipole momen...

Vitronectin (VN), one of the extracellular matrix proteins, controls the maturation of cerebellar granule cells (CGCs) through the promotion of the initial differentiation stage progress. However, the receptors of VN in the initial differentiation stage of CGC precursors (CGCPs) have not been clarified. In this study, we characterized the receptor candidates for VN in CGCPs. First, we confirmed that αvβ3 and αvβ5 integrins, which are receptor candidates for VN, were co-localized with VN in the developing cerebellum and primary cultured CGCPs. Next, the knockdown (KD) of αv, β3, and β5 integrins with small interference RNA (siRNA) for each integrin reduced the ratio of Tuj1, a final differentiation marker, -positive CGCPs. We further studied whether αvβ3 and αvβ5 integrins control the initial differentiation stage. The KD of αv and β5, but not β3, integrins significantly increased the ratio of transient axonal glycoprotein 1 (TAG1), an initial differentiation marker, -positive CGCPs, whereas the KD of αv and β3 integrins, not β5 integrin, stimulated the proliferation of CGCPs. Overexpression of β5 integrin stimulated the progress of the initial differentiation stage as well. To confirm the interaction between αvβ5 integrin and VN, VN was added to β5 integrin-KD CGCPs. The promotion of the progress of initial differentiation by VN was abrogated by β5 integrin KD using small hairpin RNA (shRNA). Taken together, our results indicated that αvβ5 integrin, as the very receptor of VN, is responsible for the progress of the initial differentiation stage in mouse CGCPs.

A hybrid solar cell composed of a crystalline semiconductor and polymer film has attracted much attention due to numerous advantages, such as high mobility, long lifetime, and the aqueous solution processing. Recently, the power conversion efficiency (PCE) of the hybrid solar cell of silicon (Si) wafer and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is reported to be higher than that of a commercial amorphous Si solar cell. Here in the Si/PEDOT:PSS hybrid solar cell was prepared using dimethyl sulfoxide (DMSO) as an additive to the PEDOT:PSS solution. The PCE was increased up to 10-fold by the addition of DMSO at a concentration of 5 wt%. Results from grazing-incidence X-ray diffraction, atomic force microscopy, and Raman spectroscopy indicated the 10-fold enhancement was controlled by the nanostructure of the PEDOT:PSS film. The enhanced performance was attributed to (i) an increase of π–π stacking, (ii) shortened distances between π–π planes, (iii) an increase in the quinoid stru...

Vitronectin (VN), which is an extracellular matrix protein, is known to be involved in the proliferation and differentiation of primary cultured cerebellar granule cell precursors (CGCPs); however, the effect of VN is not fully understood. In this study, we analyzed the effects of VN loss on the proliferation and differentiation of CGCPs in VN knockout (VNKO) mice in vivo. First, immunohistochemistry showed that VN was distributed in the region from the inner external granule layer (iEGL) through the internal granule layer (IGL) in wild-type (WT) mice. Next, we observed the formation of the cerebellar cortex using sagittal sections of VNKO mice at postnatal days (P) 5, 8 and 11. Loss of VN suppressed the ratio of NeuN, a neuronal differentiation marker, to positive cerebellar granule cells (CGCs) in the external granule layer (EGL) and the ratio of CGCs in the IGL at P8, indicating that the loss of VN suppresses the differentiation into CGCs. However, the loss of VN did not significantly affect the proliferation of CGCPs. Next, the effect of VN loss on the initial differentiation stage of CGCPs was examined. The loss of VN increased the expression levels of Transient axonal glycoprotein 1 (TAG1), a marker of neurons in the initial differentiation stage, in the cerebella of VNKO mice at P5 and 8 and increased the ratio of TAG1-positive cells in the primary culture of VNKO-derived CGCPs, indicating that the loss of VN accumulates the CGCPs in the initial differentiation stage. Taken together, these results demonstrate that VN promotes the progress of the initial differentiation stage of CGCPs.

An efficient chromium(II)-mediated reductive coupling reaction of various CBrF2-containing molecules and aldehydes has been developed. This reaction proceeds presumably via the monofluorinated dichromium(III) intermediate generated by the carbon–fluorine bond activation, and provides a general and straightforward access to synthesize a variety of (E)- or (Z)-β-fluoroallylic alcohols in a highly stereoselective manner. Based on the novel reductive coupling, four types of fluoroalkene dipeptide analogues could be stereoselectively prepared.

Treatment of β-fluoroalkylated α,β-unsaturated ketones with 10.2 equiv of triethylsilane in the presence of 3 mol% of Co 2 (CO) 8 in dichloroethane at the reflux temperature for 4 h gave 1,4-hydrosilylated adducts in a highly regio- and stereoselective manner. Thus-obtained silyl enol ethers underwent a smooth Mukaiyama aldol reaction with benzaldehyde in the presence of 1.2 equiv of TiCl 4 in CH 2 Cl 2 at −78 °C for 1 h, affording the corresponding α-(2,2,2-trifluoroethyl)-β-hydroxy ketones with high syn stereoselectivity in good yields.

We have identified novel CE conditions for the separation of 7-amino-4-methylcoumarin-labeled monosaccharides and oligosaccharides from glycoproteins. Using a neutrally coated capillary and alkaline borate buffer containing hydroxypropylcellulose and ACN, saccharide derivatives form anionic borate complexes, which move from the cathode to the anode in an electric field and are detected near the anodic end. Excess labeling reagents and other fluorescent products remain at the cathodic end. Fluorimetric detection using an LED as a light source enables determination of monosaccharide derivatives with good linearity between at least 0.4 and 400 μM, may correspond to 140 amol to 140 fmol. The lower LOD (S/N = 5) is only 80 nM in the sample solution (ca. 28 amol). The results were comparable to reported values using fluorometric detection LC. The method was also applied to the analysis of oligosaccharides that were enzymatically released from glycoproteins. Fine resolution enables profiling of glycans in glycoproteins. The applicability of the method was examined by applying it to other derivatives labeled with nonacidic tags such as ethyl p-aminobenzoate- and 2-aminoacridone-labeled saccharides.

An efficient chromium(II)-mediated reductive coupling reaction of various CBrF2-containing molecules and aldehydes has been developed. This reaction proceeds presumably via the monofluorinated dichromium(III) intermediate generated by the carbon–fluorine bond activation, and provides a general and straightforward access to synthesize a variety of (E)- or (Z)-β-fluoroallylic alcohols in a highly stereoselective manner. Based on the novel reductive coupling, four types of fluoroalkene dipeptide analogues could be stereoselectively prepared.

We achieved the purification of three alpha-keto ester reductases (Streptomyces avermitilis keto ester reductase, SAKERs-I, -II, and -III) from Streptomyces avermitilis NBRC14893 whole cells. The molecular masses of the native SAKERs-I, -II, and -III were estimated to be 72, 38, and 36 kDa, respectively, by gel filtration chromatography. The subunit molecular masses of SAKERs-I, -II, and -III were also estimated to be 32, 32, and 34 kDa, respectively, by SDS-polyacrylamide gel electrophoresis. The purified SAKERs-II and -III showed a reducing activity for alpha-keto esters (in particular, for ethyl pyruvate). SAKER-I showed a high reducing activity not only toward the alpha- and beta-keto esters, but also toward alpha-keto acid. The N-terminal region amino acid sequences of SAKERs-I, -II, and -III were identical to that of a putative oxidoreductase, SAV2750, a putative oxidoreductase, SAV1849, and a putative oxidoreductase, SAV4117, respectively, hypothetical proteins coded on the S. avermitilis genome.

We investigated postural sway in young subjects who were asked to rotate the head in the direction of visual targets. Thirteen subjects wore a helmet and stood on a force plate. They were asked to look at the targets quickly by directing the laser spot attached to the helmet on the target. Every subject showed consistent changes in the ground reaction force (Fx, Fy, Fz) and in the center of pressure (COP) associated with head movements. In 31% of all trials, force changes in Fx, Fy and Fz preceded head movements. During downward head movements, the anterior-posterior component of COP (COPx) exhibited the largest changes and the shortest latency. Ground reaction force in the anterior-posterior direction (Fx) also showed changes before the onset of downward head movements in 85% of the subjects (mean latency=-20 ms). However, the mean latency in other movements lagged behind the head movement onset. Electromyographic activities (EMGs) of the biceps femoris preceded the initiation of downward head movements by 22-54 ms in 2 subjects. These results indicate that goal-directed rotational head movements elicit COP changes. In addition, the COP changes preceding downward head movement suggest preparatory reactions related to anticipatory postural adjustments (APAs).

Co-catalyzed hydrosilylation of β-fluoroalkylated unsaturated ketones (I) affords the hydrosilylated adducts (III) in a highly regio- and stereoselective fashion.

We previously developed antioxidative heat-processed (HP)-koji via two-step heating (55 °C/2days → 75 °C/3 days) of white-koji. In this study, we isolated antioxidants in HP-koji and investigated their formation mechanisms. The antioxidants were identified to be 5-hydroxymethyl furfural (HMF) and 5-(α-D-glucopyranosyloxymethyl)-2-furfural (GMF) based on nuclear magnetic resonance spectral analysis. HMF and GMF were not present in intact koji, but were formed by heating at 75 °C. As production of these antioxidants was more effective by two-step heating than by constant heating at 55 °C or 75 °C, we presumed that the antioxidant precursors are derived enzymatically at 55°C and that the antioxidants are formed subsequently by thermal reaction at 75 °C. The heating assay of saccharide solutions revealed glucose and isomaltose as HMF and GMF precursors, respectively, and thus the novel finding of GMF formation from isomaltose. Finally, HMF and GMF were effectively formed by two-step heating from glucose and isomaltose present in koji.