Fate of the glucose degradation products 3-deoxyglucosone and glyoxal during peritoneal dialysis

Conventional fluids for peritoneal dialysis (PD) contain reactive glucose degradation products (GDPs) as a result of glucose breakdown during heat-sterilization. GDPs in PD fluids (PDFs) have been associated with the progressive alteration of the peritoneal membrane during long-term PD by cytotoxic effects and formation of advanced glycation endproducts (AGEs). In this study, we investigated the possible fate of two characteristic GDPs, 3-deoxyglucosone (3-DG) and glyoxal, during PD. In vivo, 3-DG and glyoxal concentrations, which were analyzed by high-performance liquid chromatography (HPLC), decreased in PDFs by 78% and 88% during 4 h of dwell time. The PDFs were then incubated in vitro in the presence of the most important reaction partners of GDPs in the peritoneal cavity. Neither human peritoneal mesothelial cells, human peritoneal fibroblasts, soluble protein, an insoluble collagen surface, nor components of spent dialysate led to a significant reduction of 3-DG or glyoxal after 6 h. Only after long-term incubation, a noticeable decrease of 3-DG was observed (-37% after three weeks), more likely due to spontaneous degradation reaction than formation of advanced glycation endproducts. These results suggest that in the course of PD, 3-DG, and glyoxal are absorbed into the organism and thus might contribute to the systemic pool of reactive carbonyl compounds.     

DNA and chemical analyses of commercial fly agaric-related products

Since June 6, 2002, psilocin and psilocybin-containing fungi (commonly called "magic mushrooms") have been regulated by the Narcotics and Psychotropics Control Law in Japan. However, various fly agaric-related products are now entering the Japanese market via the internet. In this study, fly agaric-related products available in this way were investigated for raw materials by DNA analysis and for additives by chemical analysis. Nucleotide sequence analysis of the mitochondrial 12S rDNA region suggested that these fly agaric-related products originate from A. muscaria or A. muscaria var. persicina. Furthermore, they were classified into three strains based on the ITS2-LSU nucleotide sequence. Harmine derivatives and/or tryptamine derivatives were detected in some of these products by LC/MS analysis. In accordance with this, the matK gene of Peganum harmala was found in all of the harmine derivative-containing samples.     

A novel spread slotted Aloha system with channel load sensingprotocol

This paper presents a novel spread slotted Aloha system with channel load sensing protocol (CLSP). CLSP is an effective scheme to improve the throughput performance in spread unslotted Aloha systems. In spread slotted Aloha systems, however, it does not make sense to utilize CLSP because the slot size is usually the same as the packet size. The slot size of the proposed system is set less than the packet size, thereby enabling the authors to apply CLSP and improving the throughput performance. Another feature of the proposed system is that the system is not likely affected by the time difference between channel load sensing and timing of packet access, which they call the access timing delay. Throughput performance of the proposed system is evaluated in the presence of the access timing delay and a significant increase of the throughput is shown compared with that of spread unslotted Aloha with CLSP     

The use of various metal carbonyls as catalyst precursors for coal hydroliquefaction

The catalytic activity of metal carbonyl complexes of chromium, molybdenum, tungsten, manganese, iron, cobalt, and nickel in the liquefaction of coal (Illinois No. 6, Wandoan and Mi-ike) was investigated. The carbonyl compounds of molybdenum, tungsten, iron, cobalt, and nickel acted as highly active catalysts for the liquefaction of Illinois No. 6 coal, resulting in high coal conversion (>90%) and high oil yield (>32%), under hydrogen pressure of 50 kg cm^?1 in a nonhydrogen-donating solvent at 425°C for 60 min. Among the catalysts surveyed, Mo(CO)₆ gave the highest oil yield (57.7%) and the largest amount of hydrogen transferred to coal (3.1 wt.% of d.a.f. coal). However, the molybdenum and tungsten carbonyls did not exhibit high catalytic activity for low sulfur Wandoan coal in the absence of added sulfur. On the other hand, cobalt and nickel carbonyls showed high catalytic activity irrespective of the amount of sulfur in the reaction system. Fe(CO)₅Mo(CO)₆ binary catalyst promoted hydroliquefaction of Wandoan coal, resulting in increases in oil yield and transfer of hydrogen to coal in the presence of sulfur.     

Catalytic steam gasification of Yallourn coal using sodium hydridotetracarbonyl ferrate

Catalytic steam gasification of Yallourn coal using sodium hydridotetracarbonyl ferrate was carried out in a semi-flow-type fixed-bed reactor at 873 and 973 K at atmospheric and high pressures. With Na[HFe(CO)₄] (Fe 1.67 wt%, Na 0.68 wt%), the steam gasification of the coal was more highly promoted than with Na₂CO₃ (Na 2.17%) and the coal was almost completely burnt out. The gasification rate decreased with increasing carbon burnoff with or without catalyst at 873 K, but increased in the presence of the catalyst at 973 K. Under pressurized steam (0.4 MPa), the catalyst exhibited higher activity. The char, obtained from Yallourn coal under argon at 823 K for 2 h, gasified under steam partial pressures of 0.4 and 0.8 MPa behaved the same as the original coal and no increase in gasification rate with steam pressure was observed. X-ray diffraction analysis showed that Na[HFe(CO)₄] was converted to Fe₃O₄ and Na₂CO₃ during the reaction.     

Influence of dielectric fluctuation on light-scattering properties of random copolymers in bulk

Polarized light scattering in bulk polymers is positively correlated with the intensity of dielectric fluctuation and the size of the heterogeneous structure, which is expressed by a correlation length. In this study, the influence of dielectric fluctuation was independently investigated for the first time on the basis of the difference in the light-scattering properties between two random copolymers – methyl methacrylate (MMA)/pentafluorophenyl methacrylate (PFPMA) and MMA/phenyl methacrylate (PMA). These copolymers have similar correlation lengths but show different intensities of dielectric fluctuation. When the difference of the mean-square average of the fluctuations of all dielectric constants between the copolymers was 105 × 10⁻¹⁰, the difference in isotropic light-scattering loss was 425 dB/km at 633 nm.     

Dehydrogenation of light alkanes over oxidized diamond-supported catalysts in the presence of carbon dioxide

Oxidized diamond demonstrated excellent support for the dehydrogenation of light alkanes to alkenes in the presence of CO₂. Oxidized diamond-supported Cr₂O₃ and V₂O₅ catalysts exhibited comparatively higher catalytic activities in the dehydrogenation of lower alkanes in the presence of CO₂. In the dehydrogenation of propane, the oxidized diamond-supported Cr₂O₃ and V₂O₅ catalysts in the presence of CO₂ afforded nearly twofold higher activities than that in the absence of CO₂. The activity of the oxidized diamond-supported V₂O₅ catalyst in the dehydrogenation of propane increased with increasing reaction temperatures. Furthermore, in the dehydrogenation of n-butane and iso-butane, a promoting effect of CO₂ on butane conversion and butenes yields was observed over the oxidized diamond-supported Cr₂O₃ and V₂O₅ catalysts, though the promotion effect was small.

UV-Vis analyses of the fresh and the reacted catalysts in the presence and absence of CO₂ revealed that CO₂ kept the surface V₂O₅ and Cr₂O₃ in a state of oxidation slightly higher than that in the absence of CO₂.     

Effects of End Groups on the Tribochemical Reactions of Lubricants at Head-Disk Interface

Mass spectrometry was used to monitor in-situ gaseous species that were generated at the head-disk interface (HDI) in a high vacuum. It was found that the end groups of the lubricants significantly affected the wear durability at the HDI; piperonyl (–CH₂-phe = (O)₂ = CH₂) terminated Fomblin AM3001 lubricant exhibited longer life than hydroxyl (–OH) terminated Fomblin ZDOL lubricant. The continuous removal of the lubricants resulted in a continuously increasing friction coefficient. Further, the characteristics of tribochemical reactions of the lubricants (Fomblin Z series) with different end groups was investigated in details using Time-of-Flight Secondary Ion Mass Spectroscopy (TOF-SIMS) just after the sliding tests. It was found that the decomposition of the end groups was more significant than that of the backbone. The lubricants terminated with the following groups showed the following order of increasing decomposition: –CH₂O-CH₂-phe = (O)₂ = CH₂ (AM3001), –CH₂OH (ZDOL) < –CH₂OCH₂CH(OH)CH₂OH (Z Tetraol) < –CH₂(OCH₂CH₂)_nOH (ZDOL-TX), –COOH (Z Diac). The decomposition of the lubricants appeared to start from the end groups.     

In vitro and in vivo antioxidant properties of ferulic acid: A comparative study with other natural oxidation inhibitors

Ferulic acid exhibits a wide range of therapeutic effects that are attributed to its potent antioxidant capacity. However, in vitro antioxidant properties of ferulic acid have not been elucidated in detail. Evidence that polyphenols, including ferulic acid, act as antioxidants in vivo is also limited. In order to elucidate in more detail the scientific background of antioxidant activities of ferulic acid, we carried out in vitro and in vivo experiments. We focused on superoxide anion scavenging activity, xanthine oxidase inhibition activity, and chain-breaking activity. The combined antioxidant activity from radical scavenging and xanthine oxidase inhibition of ferulic acid was much weaker than that of (−)-epigallocatechin gallate (EGCG) and ascorbic acid. On the other hand, EGCG, ascorbic acid and ferulic acid exhibited chain-breaking activity and prevented ischaemia-reperfusion-associated intestinal injury. Chain-breaking activity may play a contributory role in the protective effect of ferulic acid on oxidative injury in humans and in in vivo studies.