Tatsuaki Yamaguchi

Effect of Chitosan on Renal Function in Patients with Chronic Renal Failure

The effects of chitosan have been investigated on eighty patients with renal failure undergoing long‐term stable haemodialysis treatment.

Selective synthesis of acetylene from methane by microwave plasma reactions

Abstract Non-catalytic microwave plasma technology was applied to the synthesis of acetylene from methane. Microwaves of 2.45 GHz were irradiated into a cylindrical quartz reactor connected to a vacuum line for successive supply of feed gas (pure methane). Acetylene was mainly produced with a selectivity of >90%, accompanied by

Inhibitory Effect of Fulvic Acid Extracted from Canadian Sphagnum Peat on Chemical Mediator Release by RBL-2H3 and KU812 Cells

Fulvic acid (FA) was extracted and purified from Canadian Sphagnum peat (CP-FA) and characterized by using an element analysis meter, Fourier transform infrared (FT-IR) spectroscopy, electron spin resonance (ESR) spectroscopy, and 13C-nuclear magnetic resonance (13C-NMR) spectroscopy. To investigate the antiallergic effect of CP-FA, we incubated rat basophilic leukemia (RBL-2H3) cells with 0.001–10.0 μg/ml of CP-FA and determined the β-hexosaminidase release inhibition at different response stages. The intracellular calcium [Ca2+] i level was also determined by using Fluo 3-AM, a calcium-specific fluorescent probe, and the cytotoxicity of CP-FA was determined by the 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay. The results revealed that RBL-2H3 cells incubated for 48 h with 0.001–10.0 μg/ml of CP-FA did not show any decreased viability. CP-FA inhibited the β-hexosaminidase release by IgE-sensitized, antigen-stimulated RBL-2H3 cells at the antigen-antibody binding stage and the antibody-receptor binding stage. CP-FA also inhibited histamine release from A23187 plus PMA- or compound 48/80-stimulated KU812 cells. Furthermore, there was a decrease in the intracellular [Ca2+] i level in IgE-sensitized cells incubated with CP-FA and stimulated with antigen. Our results show that CP-FA may be useful for the treatment or prevention of allergic diseases.

Brown coal conversion by microwave plasma reactions under successive supply of methane

Abstract To develop an innovative method for directly converting brown coal to relatively important fuels and synthesis gases in a single step, while simultaneously upgrading the carbon content of the residue, microwave plasma technology was applied to the direct conversion of brown coal (Yallourn). Methane under reduced pressure was supplied through a quartz reactor into the irradiation zone and reacted with the coal bed placed downstream. Both the coal conversion and the carbon content of the residue were increased with an increase of irradiation time. The yield of oily products showed a maximum value (18 wt.%) at 2 min irradiation, and the fuels were composed mainly of aliphatic hydrocarbons in the range from C 13 to C 34 . Furthermore, carbon monoxide and hydrogen accompanied by a molar fraction of

Structural Analysis of an Extracellular Polysaccharide Bioflocculant of Klebsiella pneumoniae

The glycoside composition and sequence of an extracellular polysaccharide flocculant of Klebsiella pneumoniae H12 was analyzed. GC and HPLC analysis of the acid-hydrolysate identified its constituent monosaccharides as D-Glc, D-Man, D-Gal, and D-GlcA in an approximate molar ratio of 3.9:1.0:2.3:3.6. To analyze the glycoside sequence, the polysaccharide was partially hydrolyzed by acid and enzyme treatment. GC, HPLC, TLC, MALDI-TOF/MS, and 1H- and 13C- NMR spectroscopy characterized the obtained oligosaccharides. The results clarified the partial structure of H12 polysaccharide as a linear polymer of a unit of pentasaccharide with a side chain of one D-GlcA to D-Glc moiety (see below). Although the existence of other sequences or other constituent glycosides could not be fully excluded, H12 polysaccharide must be a novel types as such a complicated unit for a polymer has not so far been reported. The partial structure of a H12 polysaccharide flocculant is also discussed in this report. →4)- α-D-Glcp-(1→2)-α-D-Manp-(1→3)-4,6-Pyr-β-D- 3 Galp-(1→4)-β-D-Galp-(1→ ↓ 1 β-D-GlcpA

Effect of iron(III) chitosan intake on the reduction of serum phosphorus in rats

Because of the widespread use of aluminium‐ and calcium‐containing phosphate binders for the control of hyperphosphataemia in patients with end‐stage renal failure, an iron(III) chitosan complex was synthesised and fed to rats to measure its effect on serum phosphorus and calcium, intestinal phosphate binding and phosphate absorption.

Theoretical Studies on Structures and Electronic State of Alkyl-Substituted Ethyl Cations

This paper describes the gas phase structural details for a series of alkyl-substituted ethyl cations 1–11 by mainly natural bond orbital (NBO) analysis. For the simplest ethyl cation, two kinds of optimized structures (nonclassical 1 and classical 2) were found to have minima on the potential surface, and the nonclassical 1 was more stable than the corresponding classical 2 by 1.19 kcal/moL at Moller-Plesset (MP) level calculations in the gas phase. The calculated values of Wiberg’s bond index revealed that the central ethylic C1–C2 bonds of the nonclassical cations 1, 6, 7, and 10 have 1.10–1.46 bond multiplicities. The compliance constant () values indicated that the cation center C1 of nonclassical 2-butyl cation 6 (0.209 A/mdyn) acquires stronger hyperconjugative stabilization from C2–R3 (C–H) bond than that of the nonclassical ethyl cation 1 (0.388 A/mdyn). Moreover, the gas phase stabilities for the alkyl-substituted ethyl cations 1–11 were also estimated by the hydride affinities based on isodesmic equations.

One-step synthesis of N,N′-dialkyl-p-phenylenediamines

Condensation of 1,4-cyclohexanedione with primary alkylamines in the presence of air afforded N,N′-dialkyl-p-phenylenediamines. Reactions occurred at room temperature and were complete within a few hours, in high atom economy and with water as the major by-product.

Nuclear magnetic resonance spectroscopic studies on the tautomerism in tetramic acid analogues and their anilides. Part 4. Interpretation of carbon-13 spectra by molecular orbital calculations

The tautomeric structures of 3-acetyltetramic acid (I), 3-acetylterionic acid (III), and their anilides (Ia)–(IIIa) in CDCl3 have been studied by Fourier-transform 13C spectroscopy. On the basis of electronic theory, 1H-partial and gated decoupling techniques allowed the assignment of all signals in the spectra. Unusual features of the spectra were the large up-field shifts of the olefinic carbon signals, and the appearance of signals for the thiol-lactone carbonyl carbons of (III) and (IIIa) at lower field than those for the amide and lactone carbonyl carbons. These features are explained in terms of the electron densities on the carbons calculated by CNDO/2 or INDO methods.

Effect of Coexistent Hydrogen on the Selective Production of Ethane by Dehydrogenative Methane Coupling through Dielectric-Barrier Discharge under Ordinary Pressure at an Ambient Temperature

The effect of coexistence of hydrogen on the product selectivity to ethane from methane by dielectric-barrier discharge (DBD) reactor was examined experimentally under ordinary pressure without use of catalyst and external heating. By the dilution of methane with hydrogen, both the increase of methane conversion and the decrease of alkene production were observed, improving the selectivities to ethane by ca. 70%.