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Biol. Chem., Vol. 381, pp. 113–119, February 2000 · Copyright © by Walter de Gruyter · Berlin · New York Effects of the Active Aldehyde Group Generated by RNA N-Glycosidase in the Sarcin/Ricin Domain of Rat 28S Ribosomal RNA on Peptide Elongation Yong-Zhen Xu and Wang-Yi Liu* Shanghai Institute of Biochemistry, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China * Corresponding author Effects of the active aldehyde group of ribose C1 at position 4324 of rat 28S rRNA, in the inactivated ribo- some generated by RNA N-glycosidases (trichosan- thin

222 I. Kilpeläinen und G. Brunow: Polymer Supported Lignin Model Compounds. 2. Holzforschung 48 (1994) 222-225 Synthesis of Polymer Supported Lignin Model Compounds Part 2. Use of the Wittig reaction in Attaching of Aldehyde Group Containing Lignin Model Compounds to Polystyrene By Ilkka Kilpeläinen1 and Gösta Brunow2 'Institute of Biotechnology and 2 Dept. of Chemistry, University of Helsinki, Helsinki, Finland Keywonds Lignin model compounds Polymer support ß-Aryl ether Wittig reaction Functional polymer Aldehyde 13C NMR Summary The Wittig reaction was used to


In this study, the salicylaldehyde hydrazone was bonded onto the side chains of poly (styrene-co-butyl acrylate), firstly obtaining a series of novel Schiff base-functionalized polymers. and using the base-containing polymers as macromolecular ligands through further reaction with EuCl3/YbCl3·6H2O, a series of polymer-rare earth complexes based on Eu(III)/Yb(III) ion were successfully prepared. The structures of the schiff base-containing polymers and their corresponding complexes were characterized by means of infrared spectra and UV spectra. The thermal properties of the functionalized polymers and complexes were investigated by TGA, and the fluorescence properties of the complexes were also researched by fluorescence spectrum. The experimental results show that the complexes have fine thermal stability likely because of the bidentate chelate effect of base-containing polymer and the conjugative effect of salicylaldehyde hydrazone group on the side chain of poly (styrene-co-butyl acrylate). More important, the salicylaldehyde hydrazone group on the side chains of poly(styrene-co-butyl acrylate) can efficaciously sensitize the fluorescence emission of the center ion due to effective intramolecular energy transfer. All the Eu(III)/Yb(III) complexes exhibit characteristic photoluminescence peaks in the visible region. The fluorescence excitation spectra of the complexes were obtained by monitoring the emission of Eu3+/Yb3+ ion at 497 nm, and the peak at 433 nm was found to be the optimal excitation peak. The concentration of salicylaldehyde hydrazone group was changed gradually with the variation of the molar ratio between the butyl acrylate and styrene (1:0.5; 1:1; 1:1.5; 1:2; 1:2.5), and the differences in their fluorescent intensity were followed, and the fluorescence intensity was very weak when the molar ratio of the butyl acrylate to styrene is equal to 1:2.5, while the fluorescence intensity reached a maximum value in the molar ratio of 1:1.

Unconventional strength additives Makhlouf Laleg and Zvan I. Pikulik, Pulp and Paper Research Institute of Canada, Pointe Claire, Quebec, Canada Keywords: Additives. Wet webs, Wet strength, Dry strength, Cationic compounds, Aldehyde groups, Starch. Zirconium compounds. Bisulfite pulps. Kraft pulps. Thermomechanical pulps. SUMMARY: Unconventional additives for increasing the strength of never-dried wet webs, dry paper and rewetted paper were investigated. It was found that handsheets made from bisulphite pulps or kraft pulps can be reinforced by cationic

exist already in unbleached pulps, but chlorine dioxide bleaching was also found to gen- erate new aldehyde groups. The reactive groups were con- cluded to originate both from carbohydrates and lignin. Keywords: aldehyde; chlorine dioxide bleaching; chlorite; chlorous acid. Introduction Chlorite is formed as an intermediate species in chlorine dioxide (ClO2) bleaching. The amount of chlorite first increases rapidly in the course of a D-stage after which the chlorite is consumed in various reactions (Kolar et al. 1983; Svenson et al. 2005). In aqueous solution

of protein amino groups with aldehyde groups on the surface of the microspheres) was entrapped/adsorbed onto electro- chemically prepared conducting PPY-PVS films deposited on ITO. Potentiometric measurements undertaken on these conducting polymer electrodes using an ammonium ion analyzer reveal that they can be used for estimating the urea concentration in solutions from 5·10-3 mol/l to 6·10-2 mol/l. Introduction Estimation of blood urea nitrogen (BUN) is highly relevant to determine the state of kidney functions. Though laboratory methods are available

under alka- line conditions was used as a diagnostic tool to address the regioselectivity of the oxidation at low degrees of conversion. The oxidation proceeded by random oxidant attack; cluster-like or isolated oxidation patterns were excluded. The beta-alkoxy-elimination proceeded as a competitive process during reduction of DAC by sodium borohydride. Reduction was thus inevitably accompa- nied by a significant loss in molecular weight. The boro- hydride treatment decompacted the molecules by reducing the aldehyde groups and destroying hemiacetal crosslinks. As a

activities of 47 saponins pu- rified from medicinal and food plants were examined. The compounds showed various levels of both adju- vant and haemolytic activities. Soyasaponins and lablabosides showed strong adjuvant activity but little haemolytic activity. Jujubosides showed strong adju- vant and haemolytic activities. Escins showed weaker adjuvant activity than the adjuvant-control, but strong haemolytic activity. Comparison of the functional groups of each saponin revealed that the acyl residue in saponin, the aldehyde group at carbon 4 in agly- cone, and branched

been coupled by imino coupling to the free aldehyde groups of that network. ε-Aminocaproic acid has been used as an agent to block unspecific binding sites. The ELISA was run in a competitive mode, where the immobilized ELISA hapten and the solute terbuthylazine as a target analyte compete for the solute anti- body. Key words: Indirect Format ELISA, Graphite, Triazines Introduction Today enzyme-linked immuno-sorbent assays (ELISAs) are commonly applied to trace level analyses in aqueous systems. Competitive systems are by far dominating for the determination of low

investigated. The reaction proceeds under mild aqueous conditions (sodium citrate buffer pH 6, 308C) and introduces primarily aldehyde groups into cellu- lose so that carboxyl groups amount to one-third to one-fifth of the carbonyl groups only. LMS treatment caused uniform oxidation of the material, also in the high-molecular weight area, which is a non-typical behavior compared to other chemical oxidations of cellulose. Treatment of the pulp only with TEMPO or only with laccase caused no changes what- soever, whereas treatment with the TEMPO-derived oxoam- monium ion (in