The title compound of a lantern-type rhodium(II) dinuclear complex, cis-[Rh₂^II(

--pf )₂(O₂CCMe₃)₂(py)₂] (--pf⁻ = N,N′-di-p-tolylformamidinate anion; py = pyridine), was isolated and the crystal structure was determined by the single-crystal X-ray diffraction method at 150 K. It crystallizes in the monoclinc space group P2₁/c with a = 17.4169(2)Å, b = 12.7032(2)Å, c = 21.4293(3)Å, β = 92.311(1)°, V = 4737.38(11)ų, D_x = 1.420 g/cm³, and Z = 4. The R₁ [I > 2σ(I)] and wR₂ (all data) values are 0.0245 and 0.0664, respectively, for all 7864 independent reflections. Two Rh^II atoms are bridged by two --pf⁻ and two pivalato ligands in the cis-(2:2) fashion. The axial sites of the dinuclear core are occupied by py ligands with distances of Rh-N_ax = 2.2816(18) and 2.3458(19)Å. The Rh–Rh distance is 2.4630(2)Å, of which value is in the range of those for the other lantern-type dirhodium complexes with formamidinato ligands.

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The title polymer compound with chlorobenzene as crystal solvents [Rh₂^II(

--pf )₂(O₂CCMe₃)₂(1,4-dib)]_n·n(chlorobenzene) (--pf⁻ = N,N′-di-p-tolylformamidinate; 1,4-dib = 1,4-diisocyanobenzene) was isolated and the crystal structure was determined by the single-crystal X-ray diffraction method at 150 K. It crystallizes in the triclinc space group P1 with a = 10.6491(8)Å, b = 12.5796(11)Å, c = 19.3388(15)Å, α = 85.901(5)°, β = 77.146(5)°, γ = 85.792(5)°, V = 2514.9(4) ų, D_x = 1.446 g/cm³, and Z = 2. The R₁ [I > 2σ(I)] and wR₂ (all data) values are 0.0555 and 0.1563, respectively, for all 8757 independent reflections. Two Rh^II atoms are bridged by two --pf⁻ and two pivalato ligands in the cis-(2:2) fashion. The axial sites of the dinuclear core are occupied by 1,4-dib ligands with distances of Rh–C_ax = 2.129(6) and 2.129(7)Å to form a chain structure with alternated arrangement of cis-[Rh₂^II(--pf )₂(O₂CCMe₃)₂] and 1,4-dib. The Rh–Rh distance is 2.4845(6)Å, which is longer than the observed range for those of the lantern-type dirhodium(II) complexes with formamidinato and pivalato bridges and axially coordinating nitorgen atoms, reflecting the strong donor properies of the 1,4-dib carbon atoms. The diffuse reflectance spectra and adsorption properties for N₂ were also examined.

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In the presence of Me₃SiCl or MgCl₂, Ti(OR)₄ was reduced by Mg powder in THF to gradually generate a specific low-valent titanium species, which mediated or catalyzed several synthetic reactions such as C-O bond-cleavage of allyl and propargyl ethers and esters, intra- and intermolecular cyclotrimerization of alkynes, reduction of epoxides and oxetanes via homolytic ring-opening, McMurry coupling reaction of aryl aldehydes, imino-pinacol coupling and reductive N-S or O-S bond-cleavage of sulfonamides or sulfonyl esters.

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Successful cloning requires reprogramming of epigenetic information of the somatic nucleus to an embryonic state. However, the molecular mechanisms regarding epigenetic reprogramming of the somatic chromatin are unclear. Herein, we transferred NIH3T3 cell nuclei into enucleated mouse oocytes and evaluated the histone H3 dimethyl-lysine 4 (H3K2) dynamics by immunocytochemistry. A low level of H3K2 in the somatic chromatin was maintained in pseudo-pronuclei. Unlike in vitro fertilized (IVF) embryos, the methylation level of nuclear transfer (NT) embryos was significantly increased at the 8-cell stage. NT embryos showed lower H3K2 intensity than IVF embryos at the 2-cell stage, which is when the mouse embryonic genome is activated. Moreover, the H3K2 signal was weak in the recloned embryos derived from single blastomeres of the NT embryos, whereas it was intense in those from IVF embryos. Two imprinted genes, U2afbp-rs and Xist, were abnormally transcribed in cloned embryos compared with IVF embryos, and this was partly correlated to the H3K2 level. Our results suggest that abnormal reprogramming of epigenetic markers such as histone acetylation and methylation may lead to dysregualtion of gene expression in cloned embryos.

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The morphology and magnetic properties of ultrafine Me_1-xZn_xFe₂O₄ particles (Me=Mn²⁺, Co²⁺, Ni²⁺, Cu²⁺) prepared by a chemical coprecipitation with no subsequent heating method have been explored. The X-ray diffraction data and TEM observations indicate that cubic-structured spinel particles are formed in granular shape in the entire region of Zn2+ concentration for every case only except for a case at X=0 of Me=Ni²⁺. An incremental linear relation between the lattice parameter and Zn²⁺ concentration is also observed for Me=Co²⁺, Ni²⁺ and Cu²⁺, but not for Me=Mn²⁺ with no simple relations, while the crystallite size (D₃₁₁) obtained from X-ray line broadening, which is consistent with TEM observations as well, decreases with the higher Zn²⁺ concentration for all cases, nevertheless the coercivity (1Hc) decreases, in other words the magnetic property is softened as is verified with mossbauer measurements.
Although the trend in enhanced variation of the saturation magnetization with Zn²⁺ contents is similar to one for bulk materials for X=0-0.6 regions, the values are always small compared to bulk values, for more than X=0.6 the effect of high magnetic moment of ultrafine ZnFe₂O₄ plays a role. To interpret the low magnetization, by assuming a core model and a presence of magnetically inactive surface layer in a particle, the thickness of the layer is obtained for each sample. A correlation of the larger thickness with the larger magnetical softness of the relevant materials has been suggested.

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Lysine-specific demethylase 1 (LSD1/KDM1A), a histone-modifying enzyme, is upregulated in many cancers, especially in neuroblastoma, breast cancer and hepatoma. We have established a simple method to measure LSD1 activity using a synthetic N-terminal 21-mer peptide of histone H3, which is dimethylated at Lys-4 (H3K2). After the enzyme reaction, a substrate of H3K2 and two demethylated products, H3K1 and H3K0, were quantitatively determined by flow injection time-of-flight mass spectrometry (FI-TOF/MS). By using recombinant human LSD1, a nonlinear fitting simulation of the data obtained by FI-TOF/MS produced typical consecutive-reaction kinetics. Apparent K_m and k_cat values of hLSD1 for the first and second demethylation reactions were found to be in the range of reported values. Tranylcypromine was shown to inhibit LSD1 activity with an IC₅₀ of 6.9 µM for the first demethylation reaction and 5.8 µM for the second demethylation reaction. The FI-TOF/MS assay revealed that the endogenous LSD1 activity was higher in the nuclear extracts of SH-SY5Y cells than in HeLa or PC-3 cells, and this is in accordance with the immunoblotting data using an anti-LSD1 antibody. A simple, straightforward FI-TOF/MS assay is described to efficiently measure LSD1 activity in the nuclear extracts of cultured cells.

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A β-glucuronidase purified from a commercial pectolytic enzyme preparation of Aspergillus niger hydrolyzed about half of the 4-O-methyl-glucuronic acid (--GlcA) residues located at the nonreducing terminals of (1→6)-linked β-galactosyl side chains of the carbohydrate portion of a radish arabinogalactan-protein (AGP) modified by treatment with fungal α-L-arabinosidase. Digestion of the α-L-arabinosidase-treated AGP with exo-β-(1→3)-galactanase released, by exo-fission of β-(1→3)-galactosidic bonds in the backbone chains of the AGP, neutral β-(1→6)-galactooligosaccharides with various chain lengths and their acidic derivatives substituted at their nonreducing terminals with --β-GlcA groups. In contrast, successive digestion of the α-L-arabinosidase-treated AGP with β-glucuronidase followed by exo-β-(1→3)-galactanase liberated much higher amounts of β-(1→6)-galactooligomers together with a small portion of short acidic oligomers, mainly --β-GlcA-(1→6)-Gal and --β-GlcA-(1→6)-β-Gal-(1→6)-Gal. These results indicate that β-glucuronidase acts upon --β-GlcA residues in long (1→6)-linked β-galactosyl side chains of the AGP, whereas short acidic side chains survive the attack of the enzyme.

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Previously, we identified four metabolites of (−)-epicatechin in blood and urine: (−)-epicatechin-3'-O-glucuronide (E3'G), 4'-O-methyl-(−)-epicatechin-3'-O-glucuronide ('3'G), (−)-epicatechin-7-O-glucuronide (E7G), and 3'-O-methyl-(−)-epicatechin-7-O-glucuronide (3'ME7G) (Natsume et al. Free Radical Biol. Med. 34, 840-849, 2003). The aim of the current study was to compare the antioxidative activities of these metabolites with that of their parent compound. After oral administration of (−)-epicatechin, E3'G and '3'G were isolated from human urine, and E7G and 3'ME7G isolated from rat urine. We found that these compounds inhibited peroxynitrite-mediated tyrosine nitration, in the following order of potency: E3'G > (−)-epicatechin > E7G = 3'ME7G. = '3'G. These results demonstrate that the metabolites of (−)-epicatechin retain antioxidative activity on peroxynitrite-induced oxidative damages to some extent.

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(−)-Epigallocatechin-3-O-(3-O-methyl)gallate (EGCG3″Me) and (−)-epigallocatechin-3-O-(4-O-methyl)gallate (EGCG″) are O-methyl derivatives of (−)-epigallocatechin-3-O-gallate (EGCG) present in tea cultivars such as Benifuuki. Although O-methyl EGCGs have various bioactivities, their bioavailabilities have not been determined. In this study, we compared the bioavailability of EGCG and O-methyl EGCGs in rats, and clarified the pharmacokinetics of O-methyl EGCGs. Following oral administration (100 mg/kg), the areas under the concentration–time curves (AUCs) for EGCG, EGCG3″Me, and EGCG″ were 39.6±14.2 µg·h/L, 317.2±43.7 µg·h/L, and 51.9±11.0 µg·h/L, respectively. The AUC after intravenous administration (10 mg/kg) was 2772±480 µg·h/L for EGCG, 8209±549 µg·h/L for EGCG3″Me, and 2465±262 µg·h/L for EGCG″. The bioavailability of EGCG3″Me (0.38%) was the highest (EGCG: 0.14% and EGCG″: 0.21%). The distribution volume of EGCG3″Me (0.26±0.02 L/kg) was the lowest (EGCG: 0.94±0.16 L/kg and EGCG″: 0.93±0.14 L/kg). These results suggested that the higher AUC of EGCG3″Me after oral administration was related to its high bioavailability and low distribution volume. These findings supported the stronger bioactivity of EGCG3″Me in vivo.

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The molecular structure of the title compound, [Fe(oep)(2,-)] (where oep is dianion of octaethylporphyrin and 2,- is 2,4-dimethylphenylcyanamide), was determined by single-crystal X-ray diffraction. Crystal data: crystal system, triclinic; space group, P1 and Z = 2, a = 12.3969(8)Å, b = 13.8021(9)Å, c = 14.1594(9)Å, α = 61.093(3)°, β = 68.734(3)°, γ = 71.950(4)°, R₁ = 0.046; wR₂ = 0.094 for all data.

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We have established the preparation process of hexagonal U-type ferrites (Me=Co, Ni, Mg) and investigated their crystal structure and magnetic properties. The U-type ferrite single phase was not fabricated by using a conventional ceramic synthesis process which comprises two-steps: calcination and sintering. We have found that the U-type ferrites single phase can be obtained by a one-step sintering method that skips the calcination process. The single phase of the U-type ferrite was formed at a very narrow temperature at about 1250°C. The values of saturation magnetization and the Curie temperature of Co₂U ferrite were higher than those of Co₂Z ferrite. Initial permeability of Co₂U ferrite has a higher value than those of Ni₂U and Mg₂U ferrites. The U-type ferrite has a great potential for high frequency magnetic materials.

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【目的】初期胚を取り巻く環境要因によるエピゲノムの変容は，初期胚発生のみならず胎子発育，出生後の成長や健康にも長期にわたって影響しうる。初期胚期のエピジェネティック修飾の長期影響を解析する前段階として，初期胚と成長後の体組織の修飾の特異性と共通性を明らかにすることは重要と考えられる。本研究では，産業動物として重要なウシにおいて，胚盤胞のヒストンメチル化情報を代表的な修飾であるH3K

3について明らかにし，既存の肝臓のデータと比較解析することにより，両者の特異性と共通性を明らかにすることを試みた。特に初期胚期の環境による長期影響に大きく関与するインプリント遺伝子に着目した。【方法】食肉市場由来ウシ卵巣から卵母細胞を採取し，体外受精により胚盤胞を作製した。胚盤胞約10個からなる3群についてH3K3抗体を用いてChIP-seq解析を行った。肝臓についてはVillar et al., (Cell, 2015）によるE-MTAB-2633に登録されている若齢雄牛のデータの内2頭を用いた。【結果】胚盤胞と肝臓について，それぞれ約20,000および14,000のH3K3ピークを得た。胚盤胞と肝臓で重複しない組織特異的ピークは，7,901および1,899ピークであった。これらのピーク近傍の遺伝子の内，転写開始点の上下3 kbのピーク被覆率が大きいものから上位100遺伝子でオントロジー解析を行うと，肝臓では肝臓の代表的機能に関わるターム，胚盤胞では胚発生に関わるタームが上位に濃縮された。胚盤胞と肝臓で共通のピークを転写開始点付近に持つ29個のインプリント遺伝子のピークの面積について主成分分析を行ったところ，第一主成分方向では共通の修飾でありながらも組織特異性が強い成分，第二主成分方向では個体差や条件差を反映していると考えられる成分が抽出された。これらのことからゲノムワイドなH3K3修飾の解析により，胚盤胞の作製条件の特徴づけや体組織と比較した場合の特異性や共通性の抽出が可能であると考えられた。

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モノチオテノイルトリフルオロアセトン(STTA=Hstta)と1,10-フェナントロリン(phen)による亜鉛(II)とカドミウム(II)の協同抽出系へのピリジン塩基,すなわちピリジン(py)又は4-メチルピリジン(--py)の添加効果を検討した.pyと--pyは,カドミウムに対して抽出率を増大させる効果を示し,その効果は--pyを用いた場合のほうが大きかった.一方,亜鉛に対してはそれらの添加効果は認められなかった.又,上記金属イオンの半抽出pHの差は,ピリジン塩基の添加により増大し,両金属イオンの相互分離の度合いが改善されることが示された.

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Anodic oxidations of benzenesulfenanilides (4'-OMe (I), '- (II), 4'-Cl (III), 4'-H (IV) ) and 2-nitrobenzenesulfenanilides (4'-OMe (V), '- (VI), 4'-Cl (VII), 4'-H (VIII) ) were carried out in acetonitrile containing 0.1 M NaClO₄. electrolyses of I, II, V, VI, and VII gave the corresponding 2, 7-disubstituted phenazines, whereas those of III, IV, and VIII did not. The R-N. intermediates are suggested for the formation of the phenazines.

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【背景】LHサージによる顆粒膜細胞（GCs）の黄体化過程では劇的な細胞の機能的変化が起こる。そこで，黄体化における遺伝子発現とヒストン修飾の経時的変化をゲノムワイドに調べた。【方法】3週齢マウスにeCG 4 IU投与，48 h後にhCG 5 IU投与前，投与後4 h，12 hのGCsを回収した。RNAシークエンスとH3K

3のChIPシークエンスを行った。【結果】 4 hで発現増加した遺伝子は2077遺伝子，減少した遺伝子は1728遺伝子であった。4 hから12 hで発現増加した遺伝子は1494遺伝子，減少した遺伝子は1778遺伝子であった。H3K3が4 hで増加した領域は6223領域，減少した領域は3999領域，4 hから12 hで増加した領域は3228領域，減少した領域は6563領域であった。mRNA発現変化とH3K3変化のパターンが一致する遺伝子群について，それぞれgene ontology解析，pathway解析を行った。①H3K3とmRNA発現が4 hで増加した後，12 hまで変化しない遺伝子は細胞の形態制御に関与していた。②4 hで減少した後12 hまで変化しない遺伝子は細胞の成長抑制に関与していた。この2群の結果から，黄体化GCsの形態やサイズの増大にH3K3による発現制御が関与していたことがわかった。③4 hで増加した後12 hで減少した遺伝子はステロイドホルモン合成に関与していた。④4 hで変化せず12 hで増加した遺伝子は酸化ストレスへの反応に関与し，酸化ストレス防御にH3K3による発現制御が関与していた。⑤4 hで変化せず12 hで減少した遺伝子はエンドサイトーシスに関与していた。⑥4 hで減少した後，12 hで増加した遺伝子は代謝やオートファジーに関与していた。H3K3による発現制御が代謝を調節し，GCsの分化に関与すると考えられた。【結論】顆粒膜細胞の黄体化過程において，ヒストン修飾変化は遺伝子発現をゲノムワイドに制御し，細胞機能を調節することで黄体化に寄与することが示された。

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Histone modification has been implicated in the regulation of mammalian spermatogenesis. However, the association of differently modified histone H3 with a specific stage of germ cells during spermatogenesis is not fully understood. In this study, we examined the localization of variously modified histone H3 in paraffin-embedded sections of adult mouse testis immunohistochemically, focusing on acetylation at lysine 9 (H3K9ac), lysine 18 (H3K18ac), and lysine 23 (H3K23ac); tri-methylation at lysine 4 (H3K3) and lysine 27 (H3K27me3); and phosphorylation at serine 10 (H3S10phos). As a result, we found that there was a significant fluctuation in the modifications; in spermatogonia, the stainings for H3K9ac, H3K18ac, and H3K23ac were strong while that for H3K3 was weak. In spermatocytes, the stainings for H3K9ac, H3K18ac, H3K23ac, and H3K3 were reduced in the preleptotene to pachytene stage, but in diplotene stage the stainings for H3K18ac, H3K23ac, and H3K3 seemed to become intense again. The staining for H3K27me3 was nearly constant throughout these stages. In the ensuing spermiogenesis, a dramatic acetylation and methylation of histone H3 was found in the early elongated spermatids and then almost all signals disappeared in the late elongated spermatids, in parallel with the replacement from histones to protamines. In addition, we confirmed that the staining of histone H3S10phos was exclusively associated with mitotic and meiotic cell division. Based upon the above results, we indicated that the modification pattern of histone H3 is subject to dynamic change and specific to a certain stage of germ cell differentiation during mouse spermatogenesis.

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配位子上の置換基の異なるキレートビスアリロキソ（アルコキソ）アミン配位子、[(O-2,4-R2C6H2-6-CH2)2{OCH2(CH2)n}]N3-、を有する各種チタン錯体を合成・同定・構造決定した。同錯体とAlMe3との反応ではヘテロ２核錯体が定量的な収率で合成でき、その構造をX線構造解析で決定することが出来た。この手法で合成したヘテロ2核錯体は、エチレン重合において、助触媒がない条件下でも触媒活性を示した。

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-はシダのカニクサ（Lygodium japonicum）原糸体上に造精器の形成を誘導する。我々はこの造精器誘導作用が動物ステロイドホルモンであるプロゲステロンおよびアロプレグナノロンにより阻害されることを報告している。今回は、合成プロゲスチン、合成女性ホルモンおよびプロゲステロン受容阻害剤が、カニクサの造精器形成に与える影響を検討した。その結果、100％造精器を誘導する条件下で、合成プロゲスチンの5α-estran-17α-ethynyl-17β-ol-3-oneと5α-estran-17α-ethynyl-3α,17β-diolを与えると、10 μMで造精器形成がそれぞれ10%、0%に低下することが示された。一方、4-pregnen-6α-methyl-17-ol-3,20-dione acetateと4-pregnen-6α-methyl-17-ol-3,20-dioneは、-の造精器誘導作用を著しく促進した。以上の結果から、カニクサはプロゲスチンを受容する部位をもつことが示唆された。また、ヒトのプロゲステロン受容阻害剤は、カニクサの造精器形成に影響しなかったため、カニクサのプロゲステロン受容体はヒトの受容体とは異なった受容特性を示すものと考えられた。

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