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Winding vine-shaped bithiophene was synthesized through the nosyl (2-nitrobenzenesulfonyl) cyclization protocol. The reaction of bithiophene bearing bromomethyl groups at the 3,3′-positions with nosylated 1,2-ethylenediamine in the presence of potassium carbonate afforded the annulated product in excellent yield. The obtained bithiophene was found to contain a 10-membered ring, which was confirmed by X-ray analysis. The related nosyldiamine bearing a tri- or tetramethylene group also reacted in a similar manner, affording an 11- or 12-membered macrocycle, respectively.

A simple and ubiquitous nickel(II) complex NiCl2(PPh3)2 catalyzes polymerization of oligothiophenes. Treatment of chlorobithiophene with chloromagnesium 2,2,6,6-tetramethylpiperidin-1-yl lithium chloride salt (TMPMgCl·LiCl) followed by addition of 2.0 mol % NiCl2(PPh3)2 undergoes deprotonative polymerization leading to poly(3-hexylthiophene) (P3HT) with Mn = 13000 and Mw/Mn = 1.67 (74% yield). The related terthiophene and quaterthiophene also polymerize to afford the corresponding polythiophene while little polymerization takes place with 2-chloro-3-hexylthiophene under similar conditions.

The synthesis, structures, and reactivity of dinuclear Fe0 complexes of N-heterocyclic carbenes (NHCs, denoted as L) are reported. The NHC adducts of ferric chloride (L)FeCl3 were prepared from the reactions of FeCl3 with L in toluene. The reduction of (L)FeCl3 with KC8 resulted in the formation of the dinuclear Fe0 complexes Fe2{μ-η1(C):η6(arene)-L}2 (2a, L = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes); 2b, L = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene (IPr)), in which NHC ligands bridge two iron atoms using one of the arene rings as an η6 ligand. Their magnetic properties are different: 2a is paramagnetic and 2b is diamagnetic. The dinuclear complexes 2a,b serve as precursors for monomeric (NHC)Fe0 species, and treatment of 2a,b with 1 atm of CO led to the formation of (L)Fe(CO)4. Complex 2a was found to react with 1-azidoadamantane, giving rise to the dinuclear tetrazene complex (IMes)Fe(μ-NAd)2Fe(AdNNNNAd) (4).

A diamine-bridged bis-N-heterocyclic carbene ligand was synthesized as imidazolium salts with chloride or triflate counteranions. Deprotonation of the chloride salt by an iron bis-amide complex or addition of the free diamine-bis-carbene ligand to FeCl2 led to the formation of an Fe(II) dichloride complex having a diamine-bis-carbene ligand, in which the iron atom is in a highly distorted octahedral geometry with weak Fe-N interactions. This iron complex was found to catalyze the hydrosilylation of acetophenone.

N-heterocyclic carbene (NHC) adducts of iron dichloride, (IMes)2FeCl2 (1a; IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene) and (IEtPh*)2FeCl2 (1b; IEtPh* = 1,3-bis((R)-1′-phenylethyl)imidazol-2-ylidene), were prepared in good yields from the reactions of Fe{N(SiMe3)2}2 with imidazolium salts. While the iron atom of 1a has a tetrahedral geometry, replacement of the chlorides by methyl groups via treatment of 1a with MeLi led to the formation of the square-planar complex trans-(IMes)2FeMe2 (2). The molecular structures of complexes 1a,b and 2 were identified by means of single-crystal X-ray diffraction analysis. Complexes 1a,b and 2 are good catalyst precursors in the transfer hydrogenation of 2′-acetonaphthone, and complex 2 also efficiently catalyzes the hydrosilylation of 2′-acetonaphthone.

Cellobiose is produced from cellulose using specific bacterial enzymes, and is hydrolyzed into glucose by the enzymes cellobiosidase and cellulase. In this study, we examined the effects of cellobiose on colonic mucosal damage in a dextran sulfate sodium (DSS) colitis model. BALB/c mice were divided into two groups. In the first group, the mice were fed 3.5% DSS mixed with normal chow. In the second group, the mice were fed 3.5% DSS plus 6.0 or 9.0% (weight/weight) cellobiose mixed with normal chow. The development of colitis was assessed on day 21. Mucosal cytokine expression was analyzed by RT-PCR. Body weight loss was significantly attenuated in the 9.0% cellobiose-fed DSS mice as compared to the DSS mice. Colonic weight/length ratio, a maker of tissue edema, was significantly higher in the DSS mice than in the 9.0% cellobiose-fed DSS mice. The disease activity index and histological colitis score were also significantly higher in the DSS mice than in the 9.0% cellobiose-fed DSS mice. Mucosal mRNA expression for IL-1beta, TNF-alpha, IL-17 and IP-10 were markedly reduced in the 9.0% cellobiose-fed DSS mice. In conclusion, a preventive effect of cellobiose against DSS colitis suggests its clinical use for inflammatory bowel diseases patients.

There have been no reports on 6-thioguanine nucleotide (6-TGN) concentrations in Japanese patients with inflammatory bowel disease (IBD) undergoing azathioprine (AZA) or 6-mercaptopurine (6-MP) therapy. The aim of this study was to assess 6-TGN concentrations in Japanese IBD patients.Eighty-three patients with Crohn's disease (n = 42) and ulcerative colitis (n = 41) were enrolled. In 69 patients, AZA was prescribed at 50 mg/day, and seven patients were given 75 (n = 5) or 100 mg/day (n = 2). 6-MP was administered at 30 mg/day (n = 7). The 6-TGN concentrations were then assayed by high-performance liquid chromatography.The mean 6-TGN concentrations of the entire study population (n = 83) were 277.9 +/- 179.8 pmol/8 x 10(8) red blood cells (RBC). The mean 6-TGN concentrations in those patients with active disease (n = 38) and those in remission (n = 45) were 232.9 +/- 159.7(mean +/- SD) and 342.8 +/- 184.6 pmol/8 x 10(8) RBC, respectively (P0.05). The odds ratio of being in remission and having a 6-TGN value235 pmol/8 x 10(8) RBC was 2.6 (95% CI 1.05-6.2). A significant inverse correlation was found between the white blood cell (WBC) counts and 6-TGN concentrations (r = -0.301, P0.05, n = 83); the mean WBC counts of the active patients (6780 +/- 2412) were significantly higher than the patients in clinical remission (5468 +/- 1920, P0.05). Three patients with severe leukopenia and 10 patients with high 6-TGN concentrations had no thiopurine S-methyl transferase mutations.The 6-TGN concentrations in Japanese patients with IBD on low-dose AZA and 6-MP therapy were comparable to those reported from Western countries. The monitoring of 6-TGN concentrations may be helpful for developing a therapeutic strategy for Japanese IBD patients.

Background and Aims Short-chain fatty acids (SCFAs), such as acetate, propionate and butyrate, are the major by-product of bacterial fermentation of dietary fiber in the colon. In this report, we investigated how SCFAs modulate matrix metalloproteinase (MMP) secretion from human colonic subepithelial myofibroblasts (SEMFs). Materials and Methods SEMFs were identified by expression of α-smooth muscle actin and vimentin. Cytokine-induced MMP-1 and MMP-3 levels were determined by enzyme-linked immunosorbent assay. Cytokine-induced MMP mRNA expression was analyzed by RT-PCR and real-time PCR methods. Results Acetate had no effect on MMP secretion. Propionate and butyrate significantly attenuated IL-1β- and TNF-α-induced MMP-1 and MMP-3 secretion. Similar responses were also observed at the mRNA levels. Propionate and butyrate did not modulate IL-1β- and TNF-α-induced activation of mitogen-activated protein kinases (MAPKs), which play a crucial role in MMP induction. Trichostatin A, a histone-deacetylase inhibitor, reduced IL-1β-induced MMP-1 and MMP-3 mRNA expression, and suppressed TNF-α-induced MMP-3 mRNA expression. Conclusion SCFAs play an anti-inflammatory role through suppression of MMP secretion in the colon. Inhibitory effects of SCFAs on MMP secretion might be associated with their action of histone hyperacetylation.

A silicon-containing apatite layer was prepared on a metallic titanium substrate coated with a silica layer. The silica layer on a titanium substrate was derived from water glass through heat-treatment at 300 °C for 2 hr and subsequent acid-treatment using 0.1 N-HCl at 50 °C for 2 hr. The silica layer was homogeneously coated with nano-sized vaterite powders (~ 0.5 μm in diameter). The vaterite coating was achieved by utilizing the interaction of surface potentials between the positively charged vaterite and the negatively charged silica layer. After soaking the sample in simulated body fluid at 37 °C for 3 days, hydroxyapatite (HA) formed on the surface of the silica-coated titanium. The HA layer was found to include a trace amount of releasable silicon, which may enhance the osteoblast proliferation.

We investigated the electrochemical behavior on the boron-doped conductive diamond electrode in HNO3 aqueous solution containing Pb2+ ions. The anodic oxidation led to the formation of a PbO2 deposit on the diamond electrode. In HNO3 solution containing less than 10 μM (M=mol/l) Pb2+ ions, a clear cathodic current peak was observed on the diamond electrode in the cathodic potential scan after holding the potential at 1.80 V vs. SCE. On both the platinum and glassy carbon electrodes, it was difficult to detect a cathodic current peak exactly in the same solution because of the large background current of these electrodes. The proportional relation between the magnitude of the cathodic current peak and the concentration of Pb2+ ions (1-10 μM) in coexistence of Cu2+ and Fe3+ ions was obtained by use of diamond electrodes pretreated with cathodic reduction and anodic oxidation in HNO3 solution. The diamond electrode also showed high ability to scavenge Pb2+ ions from the solution.

Boron-doped conductive diamond electrode showed a high response to Pb2+/PbO2 redox system in HNO3 aqueous solution. A cathodic current peak due to the reduction of PbO2 to Pb2+ was clearly observed on the diamond electrode in the cathodic potential scan after the anodic oxidation at 1.80V vs. saturated calomel electrode (SCE) for 10min in the solution containing Pb2+ ions. A linear relation between the magnitude of cathodic current peak and the concentration of Pb2+ (1-10μmo·dm-3) was obtained without interference of other metal ions (Cu2+, Fe3+, Ni2+, Mn2+) coexisting.

An oxygen-encapsulated iron sulfido cluster, [(DmpS)Fe(4)S(3)O][(DmpS)Fe(4)S(3)](μ-SDmp)(2)(μ-OCPh(3)) (2; Dmp = 2,6-(mesityl)(2)C(6)H(3)), has been synthesized by the reaction of the preformed dinuclear iron thiolate/alkoxide [(Ph(3)CO)Fe](2)(μ-SDmp)(2) (1) with (1/8)S(8) and (1/4)H(2)O in toluene. In the [Fe(8)S(6)O] core, the oxygen atom bridges unsymmetrically two incomplete Fe(4)S(3) cubes, and two coordinatively unsaturated iron atoms are weakly bound to mesityl rings. Relevance of the cluster structure of 2 to the nitrogenase FeMo cofactor and its substrate binding mode is discussed.

A novel chiral coordination polymer, [Cu(C(6)H(5)CH(OH)COO)(μ-C(6)H(5)CH(OH)COO)] (1-L and 1-D), was synthesized through a reaction of copper acetate with L-mandelic acid at room temperature. Although previously reported copper mandelate prepared by hydrothermal reaction was a centrosymmetric coordination polymer because of the racemization of mandelic acid, the current coordination polymer shows noncentrosymmetry and a completely different structure from that previously reported. The X-ray crystallography for 1-L revealed that the copper center of the compound showed a highly distorted octahedral structure bridged by a chiral mandelate ligand in the unusual coordination mode to construct a one-dimensional (1D) zigzag chain structure. These 1D chains interdigitated each other to give a layered structure as a result of the formation of multiple aromatic interactions and hydrogen bonds between hydroxyl and carboxylate moieties at mandelate ligands. The coordination polymer 1-L belongs to the noncentrosymmetric space group of C2 to show piezoelectric properties and second harmonic generation (SHG) activity.

The reactions of Fe(2)Mes(4) (1; Mes = mesityl) with bulky thiols, namely, HSDmp (Dmp = 2,6-dimesitylphenyl), HSDxp (Dxp = 2,6-dixylylphenyl), and HSBtip [Btip = 2,6-(2,4,6-(i)Pr(3)C(6)H(2))(2)C(6)H(3)], provided a series of iron(II) mesityl complexes bearing bulky thiolate ligands. These iron complexes are the thiolate-bridged dinuclear complexes Fe(2)Mes(2)(mu-SAr)(mu-Mes) (2a, Ar = Dmp; 2b, Ar = Dxp), the 1,2-dimethoxyethane (DME) adducts (DME)Fe(SAr)(Mes) (3a, Ar = Dmp; 3b, Ar = Dxp), the mixed-valence Fe(I)-Fe(II) dinuclear complexes (Mes)Fe(mu-SAr)(mu-S Ar) Fe (4a, Ar = Dmp; 4b, Ar = Dxp), and a low-coordinate mononuclear complex (B tipS) Fe(Mes) (5). An [Fe(8)S(7)] cluster [Fe(4)S(3)(SDmp)](2)(mu-SDmp)(2)(mu-SMes)(mu(6)-S) (6), the core structure of which is topologically relevant to that of the FeMo-cofactor of nitrogenase, was obtained from the reaction of 3a or 4a with S(8). The mu-SMes ligand in 6 is formed via insertion of a sulfur atom into the Fe-C(Mes) bond. The formation of cluster 6 from 3a or 4a demonstrates that organoiron complexes are applicable as precursors for iron-sulfur clusters.

Interleukin (IL)-31 is mainly produced by CD4+ T cells, in particular T cells skewed toward a Th2 phenotype. Here we report for the first time that IL-31 stimulates secretion of proinflammatory cytokines, chemokines and matrix metalloproteinases (MMPs) from human colonic subepithelial myofibroblasts (SEMFs). The effects of IL-31 were investigated by cDNA microarrays, enzyme-linked immunosorbent assay, and real-time PCR. IL-31 effectively induced chemokines [IL-8, GRO-alpha (growth-related oncogene-alpha), MCP-3 (monocyte chemoattractant protein-3), CXCL3, CCL13 and CCL15], proinflammatory cytokines (IL-6, IL-16 and IL-32) and matrix metalloproteinases (MMP-1, MMP-3, MMP-25 and MMP-7). IL-31 dose-dependently induced secretion of IL-6, IL-8, GRO-alpha, MCP-3, MMP-1 and MMP-3. The effects of IL-31 were comparable to the effects of IL-17A. IL-31 and IL-17A showed additive effects on IL-6, IL-8, GRO-alpha, MCP-3, MMP-1 and MMP-3 secretion. In conclusion, we demonstrated that IL-31 is a potent inducer of proinflammatory mediators in human colonic SEMFs. IL-31 may function as a proinflammatory cytokine derived from Th2 cells.

Many switching converters use soft-switching techniques with active-clamp snubber in order to reduce switching surge and common-mode noise. In low-voltage and large-current DC-DC converters, synchronous-rectifier circuits are used to improve the power efficiency. Self-driven synchronous-rectifier circuits are generally used because of isolation and easy control. Recently, it has been noticed that abnormal phenomenon occurs under some conditions in the DC-DC converter with both active-clamp snubber circuit and synchronous-rectifier circuit. This phenomenon occurs in both the ordinary forward converter with active-clamp snubber and common-source type forward converter. This paper describes the analysis of this abnormal phenomenon and clarifies the conditions of the abnormal phenomenon by using common-source type forward converter with self-driven synchronous rectifier circuit.

Many switching converters use soft-switching techniques with an active-clamp snubber so as to reduce switching surge and common-mode noise. In particular, the common-source type active-clamped forward converter is known as an effective circuit topology for common-mode noise reduction. On the other hand, replacing the output rectifying diodes with synchronous rectifier circuits, the power efficiency can be improved in the DC-DC converter with low-voltage and large-current output. Furthermore, the self-driven synchronous-rectifier circuits are generally used because of isolation and simple structure of their gate-driving circuits. However, for this common-source type active-clamped forward converter with self-driven synchronous rectifiers, it has been recently noticed that an abnormal phenomenon such as the inductor-current oscillation and the acoustic noise generation in the transformer occur in some conditions. This paper discusses the above-mentioned abnormal phenomenon. The cause of the abnormal phenomenon is examined and its occurrence condition is clarified.

Many DC-DC converters use soft-switching techniques with active-clamp snubber in order to reduce switching surge and common-mode noise. In particular, common-source type active-clamped DC-DC converter is one of the most useful circuit topology for reduction of common-mode noise. Furthermore, in low-voltage and large-current DC-DC converters, synchronous rectifier circuits are used to improve the power efficiency. self-driven synchronous rectifier circuits are generally used because of isolation and easy control. Recently, it has been noticed that an abnormal phenomenon occurs under some conditions in the common-source type forward converter with self-driven synchronous rectifier circuit. This paper describes the analysis of this abnormal phenomenon and clarifies the conditions of the abnormal phenomenon with experimental results.

A parallel-resonant converter featuring zero-voltage-switching and control by pulse-width-modulation is proposed. Similar to a previously proposed series-resonant counterpart, it has a simple structure and can be controlled at a constant switching frequency using an active-clamp technique. The nearly constant current output characteristic of the parallel-resonant converter lends itself beneficially to precisely controlled constant current power supply applications. An experimental breadboard featured an output-current accuracy of /spl plusmn/0.6% at 1 A over a range of input voltages from 34 to 46 V and output voltages from 2 to 20 V. A maximum efficiency of 80% was observed.

High precision and high reliability are of course required in ultra-precision machining. Today however, unmanned operation and high productivity are also required, not only in conventional precision machining but also in ultra-precision machining. In addition, surface integrity is required in ultra-precision machining. The authors think that a new concept of “Intelligent manufacturing” can satisfy these requirements. As an applied example of intelligent manufacturing, the in-process inspection system in cutting a photoconductor drum is discussed in this paper. In-process inspection in cutting a photoconductor drum is realized by detecting the average and the fluctuation of the cutting force. And the best setting angle of a diamond tool is presumably recognized by detecting the ratio between the average and the fluctuation of the principal cutting force. By this system, the requirements of high precision and high productivity may be realized simultaneously.

Reactions of manganese(II) dichlorides bearing a N-heterocyclic carbene ligand (L), [MnCl(μ-Cl)(L)]2 (1a, L = 1,3-diisopropyl-4,5-dimethylimidazole-2-ylidene (IiPr); 1b, L = 1,3-bis(2,4,6-trimethylphenyl)imidazole-2-ylidene (IMes); 1c, L = 1,3-bis(2,6-diisopropylphenyl)imidazole-2-ylidene (IPr)) with MeLi afford the dinuclear dimethylmanganese(II) complexes, [MnMe(μ-Me)(L)]2 (2a, L = IiPr; 2b, L = IMes; 2c, L = IPr). Complexes 2a-c achieve nucleophilic substitution of Si(OEt)4 to selectively form MeSi(OEt)3. Related arylmanganese(II) complexes analogously react with Si(OEt)4 to afford ArSi(OEt)3 and Ar2Si(OEt)2 (Ar = Ph, 2,6-Me2(C6H3)). Kinetic studies support an associative mechanism for the observed transformation of Si(OEt)4, in which both the manganese species and Si(OEt)4 are involved in the rate-limiting step.