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In this study, we cloned the ATP-binding cassette (ABC) subfamily G member 2 gene (Abcg2 gene; breast cancer resistance protein) from the liver of the marine pufferfish Takifugu rubripes, and examined its tissue distribution and gene structure. The full-length complementary DNA (cDNA) was 1977 base pairs (bp), comprising 15 exons in chromosome 17, and was assigned to the teleost Abcg2b paralogue. The open reading frame was 1839 bp in length, and encodes 612 amino acids constituting Walker A, Q-loop, C motif, Walker B, D-loop, and H-loop sequences in the first half and six transmembrane domains in the second half. Gene expression of Abcg2 was predominantly found in the intestines, followed by the liver and kidneys. The Kozak motif and the polyadenylation signal sequences were at respective ends of the transcript. The putative core promoter sequences including the transcription factor II B recognition elements, the TATA box, the initiator element, and the downstream core promoter element were found in the transcript and its upstream genomic DNA sequence. The hypoxia response element and the estrogen response element were located in the upstream genomic DNA sequence, suggesting that the pufferfish Abcg2 gene possesses the same regulation mechanism of transcription as the human ABCG2 gene.

Both hexachlorobenzene and hexabromobenzene were successfully hydrodehalogenated to the monohalogenated derivative and ultimately to benzene (which was subsequently reduced to cyclohexane) using a mixture of metallic Ca, ethanol, and Rh/C, by simple stirring in diethyl ether, at room or mild temperature (60 °C). Various experiments were performed in order to assess the role of the solvent and Rh/C catalyst, as well as for elucidating the reaction pathway.

A photochemical solar cell sensitized with a lignophenol, which has been directly synthesized from lignocellulosics through the phase-separation system, on a nano-porous TiO2 film electrode was developed and improved by stirring, reflux and saturation in an acetone solution. Hinoki (Chamaecyparis obtusa)-lignophenol (p-cresol type, HKLC), Beech (Fagus crenata)-lignophenol (p-cresol type, BCLC), second derivatives-I of HKLC and BCLC (HKLC413, BCLC413) and second derivatives-II of HKLC and BCLC (HKLC443, BCLC443) were used as photo-sensitizers. The conversion of visible light from 150-W Xe lamp through a L41 UV cut filter into electricity was achieved with a sandwich-type cell consisted of FTO-glass-TiO2 film-lignophenol-electrolytes-Pt coated FTO. The open circuit photovoltage (Voc), the short-circuit photocurrent density (Isc), the fill factor (FF) and the photo-electricity conversion efficiency (η) for the cell with HKLC413 saturated on TiO2 electrode were estimated under 85.0 mW cm−2 visible light irradiation for 0.51 V, 10.23 mA cm−2, 0.59 and 3.61% respectively. On the other hand, the cell with HKLC saturated only on the surface of TiO2 electrode was estimated for η = 0.81%. Moreover, the amounts of HKLC413 and HKLC443 on the electrodes extracted by 1.0 M NaOH were larger than the amount of HKLC evaluated by UV–vis spectroscopy. After the extractions were carried out in NaOH, only both HKLC413 and HKLC443 were remained in electrodes with slight yellow appearances. These results indicated that lignophenols were adsorbed on the inner part of porous TiO2 electrodes. Consequently, the performances of these cells were strongly influenced by the molecular sizes and the structures of lignophenols.

溶媒可溶で分子設計が可能な森林資源由来の天然リグニン誘導体ポリマーであるリグノフェノール (LP) とナノ多孔質酸化チタン電極を組合せた光電変換デバイスは, 可視光照射下, 安定した光電変換能力を示した. UV-vis分光の結果, 各LPはそれぞれ可視光領域で固有の波長を吸収し, ヒドロキシル基が重要な役割を果たした. LP二次誘導体は可視光吸収が大幅に増大した. LPは光照射により一重項励起し, 蛍光を発した. 分子内に複雑な内部変換などの緩和機構を有し, 導入フェノールによっては項間交差も見られた. CV分析の結果, 比較的安定なカチオンラジカルを生じる構造を有し, 電荷分離が可能な物質であった. さまざまなLPを用いて比較した結果, LP/酸化チタン錯体が重要な電子注入ルートであり, ヒドロキシル基以外にも1, 1-ビス (アリル) プロパン型ユニットが重要な相互作用をしていることが示唆された. ヒノキリグノ-p-クレゾール二次誘導体-I (HKLC413) を用いたセルで0.5V, 4.0mAcm-2, η=0.8%の光電変換能力を示した. 天然に豊富に存在する未利用炭素資源誘導体ポリマーと酸化チタンを組合せることで光励起による電荷分離が生じ, 色素増感太陽電池として機能した.

A series of new lignin derivatives (lignophenols) containing phenol, p -cresol, catechol, resorcinol and pyrogallol synthesized from Hinoki ( Chamaecyparis obtusa ) and Douglas fir ( Pseudotsuga menziessi ) as softwood and beech ( Fagas crenata ) as hardwood was investigated as sensitizers for a dye-sensitized solar cell (DSSCs) of porous TiO 2 under the irradiation of 150 W Xe lamp. For example, LPs–DSSCs of hinoki-ligno- p -cresol, directly derived from hinoki native lignin showed V oc =0.34 V, I sc =0.65 mA cm −2 , ff=0.49 and η =0.11% under AM 1.5 (100 W m −2 ). The strong interactions between lignophenols and TiO 2 surface were estimated by UV-Vis and FT-IR spectra. The importance of interactions between phenolic hydroxyl groups and TiO 2 surface was discussed by FT-IR, solid UV-Vis spectra and 1 H NMR. The effects of chemical modifications were discussed using acethylated lignophenols (LPsOAc) or re-cycled lignophenols, treated by 0.5 M NaOH at 413 K (LPs–SF413) or 443 K (LPs–SF443). These results implied interactions between LPs and TiO 2 were consisted of anchors and stacking on TiO 2 .

This study examined the urinary excretion of tetrodotoxin (TTX) modeled in a porcine renal proximal tubule epithelial cell line, LLC-PK1. Time course profiles of TTX excretion and reabsorption across the cell monolayers at 37 °C showed that the amount of TTX transported increased linearly for 60 min. However, at 4 °C, the amount of TTX transported was approximately 20% of the value at 37 °C. These results indicate that TTX transport is both a transcellular and carrier-mediated process. Using a transport inhibition assay in which cell monolayers were incubated with 50 µM TTX and 5 mM of a transport inhibitor at 37 °C for 30 min, urinary excretion was significantly reduced by probenecid, tetraethylammonium (TEA), l-carnitine, and cimetidine, slightly reduced by p-aminohippuric acid (PAH), and unaffected by 1-methyl-4-phenylpyridinium (MPP+), oxaliplatin, and cefalexin. Renal reabsorption was significantly reduced by PAH, but was unaffected by probenecid, TEA and l-carnitine. These findings indicate that TTX is primarily excreted by organic cation transporters (OCTs) and organic cation/carnitine transporters (OCTNs), partially transported by organic anion transporters (OATs) and multidrug resistance-associated proteins (MRPs), and negligibly transported by multidrug and toxic compound extrusion transporters (MATEs).