bluuebunny/crossref_metadata_2025_split huggingface dataset:
Disruption of mating in codling moth (Lepidoptera: Tortricidae) by chlorantranilipole, an anthranilic diamide insecticide
Authors: Knight Alan L , Flexner Lindsey 
Published: November 2006

AbstractThe influence of the anthranilic diamide insecticide chlorantranilipole (DPX‐E2Y45; Rynaxypyr™) against the adult stage of codling moth, Cydia pomonella L., was examined. Insecticide residues in plastic cups sprayed with 56 mg AI L−1 (equivalent to the recommended field rate) had a minimal effect on adult survival or fecundity, but significantly fewer female moths were mated in treated than in untreated cups. Similar results were found in field studies with adults placed in screened cages on treated apple foliage for up to 3 weeks. Mating was disrupted when either sex was topically dosed with technical material (0.01–0.1 µg). Males were more sensitive to the disruptive effects of chlorantranilipole than females. A 2 h exposure significantly reduced male activity (walking and wing fanning), but not female calling. A 25 h exposure significantly reduced the activity of both sexes. The proportion of males landing near a sex pheromone source in a flight tunnel was significantly reduced following exposures of 2–4 h and completely eliminated following a 17 h exposure. Male moths partially recovered from either topical or residual exposure to chlorantranilipole, but the extent of their recovery was dose and time dependent. Male response to sex pheromone recovered within 2 h following a 4 h exposure, but following a 17 h exposure only a partial recovery occurred after 48 h. Mating by moth pairs exposed to chlorantranilipole residues for 24 h did not significantly increase during recovery periods of 24–96 h, except in cups treated with 10% of the standard concentration. The proportion of field‐collected female codling moths caught in pear ester‐baited traps that were mated was significantly lower in apple orchards treated season‐long with chlorantranilipole compared with females caught in either untreated orchards or those treated with sex pheromones to cause mating disruption. Copyright © 2006 Society of Chemical Industry
Molecular dynamics study of amyloid formation of two Abl‐SH3 domain peptides
Authors: Liepina Inta , Ventura Salvador , Czaplewski Cezary , Liwo Adam 
Published: November 2006

AbstractMolecular dynamics (MD) simulations were carried out for two‐strand and ten‐strand β‐sheets constructed from two peptides corresponding to the diverging turn of two homologous Abl‐SH3 domains, DLSFMKGE (MK; from Drosophila) and DLSFKKGE (KK; from man), in explicit water at the temperatures of 30, 170/190 and 300 K. It was found that the 2 × MK β‐sheet is more stable than the 2 × KK β‐sheet, and that the 10 × MK β‐sheet is more stable than the 10 × KK β‐sheet; this suggests that the MK systems are fibril‐creating and the KK systems are not. These results might explain why most SH3 domains possess two conserved basic residues at the diverging turn, which may act as gatekeepers in order to avoid aggregation. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
Comparison of the stability of glutathione and related synthetic tetrapeptides by HPLC and capillary electrophoresis
Authors: Mahlapuu Riina , Vaher Merike , Ehrlich Kersti , Kaljurand Mihkel , Soomets Ursel 
Published: November 2006

AbstractGlutathione and related peptides are interesting targets as protectors of biological systems against an oxidative injury. Two novel glutathione analogues, UPF1 and UPF15, have been designed and synthesised. As a result of different reactions taking place, the thiol‐containing compounds oxidise to disulfides. In this study, the stability of UPF1, UPF15 and glutathione in various solutions was investigated by using HPLC and CE. The results showed that UPF1 and UPF15 are powerful hydroxyl radical scavengers and their dimerisation process velocity is higher than that of glutathione. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
‘Click peptide’: a novel ‘O‐acyl isopeptide method’ for peptide synthesis and chemical biology‐oriented synthesis of amyloid β peptide analogues
Authors: Sohma Youhei , Taniguchi Atsuhiko , Yoshiya Taku , Chiyomori Yousuke , Fukao Fukue , Nakamura Setsuko , Skwarczynski Mariusz , Okada Takuma , Ikeda Keisuke , Hayashi Yoshio , Kimura Tooru , Hirota Shun , Matsuzaki Katsumi , Kiso Yoshiaki 
Published: November 2006

AbstractAfter over a decade of studies on aspartic protease inhibitors and water‐soluble prodrugs, we have been developing a novel method, since 2003, called ‘O‐acyl isopeptide method’, for the synthesis of peptides containing difficult sequences. With our recent discoveries of ‘O‐acyl isodipeptide unit’ and the ‘racemization‐free segment condensation method’, this method has further evolved as a general synthetic method for peptides. Moreover, ‘Click Peptide’, which could be a powerful tool for identifying the pathological functions of amyloid β peptides in Alzheimer's disease, represents a valuable use of the isopeptide method in Chemical Biology‐oriented research. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
Effect of salts on the structural behavior of hPrP α2‐helix‐derived analogues: the counterion perspective
Authors: Ronga Luisa , Palladino Pasquale , Tizzano Barbara , Marasco Daniela , Benedetti Ettore , Ragone Raffaele , Rossi Filomena 
Published: November 2006

AbstractBoth theoretical studies and direct experimental evidence have emphasized the importance of electrostatic interactions in the general phenomenon of spontaneous amyloid fibril formation. A number of observations have recently spurred interest in the contribution of these interactions to the conformational behavior of the prion protein. In this paper, we show how salt addition and pH change can modify the conformation of two peptide analogues derived from the human prion protein helix 2 according to a Hofmeister‐series‐type dependence. Employment of various sodium salts allowed us to highlight the fact that chaotropic anions favor unstructured conformation, whereas kosmotropic anions promote the formation of compact structures like α‐helix and β‐sheet, which may ultimately facilitate fibril formation. This finding should warn people engaged in ion‐based research on prion and derived peptides about cation‐bound effects, which have been almost exclusively investigated to date, being easily confounded with modifications that are actually caused by anion activity, thus leading researchers into misunderstand ion‐specific effects. To avoid the common complication of ion confounding, it is highly desirable that experiments be designed so that the species causing the modification can be unequivocally perceived. Copyright © 2006 European Peptide Society and John Wiley & Sons, Ltd.
Electronic structure of tellurium under high pressure
Authors: Nishikawa Atsushi 
Published: November 2006

AbstractWe have investigated the electronic structure and the structural stability of tellurium under pressure by using the full‐potential linearized APW method. Te‐II and Te‐III have triclinic structure and incomensurate monoclinic structure respectively and we have shown that a tripling of monoclinic Te‐III unit cell along b‐axis yields a large dip in the density of states of the 5p‐band and this yields the lowering of the band structure energy to make these structures with low symmetry stable. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Resistivity relaxation of ammonium halides near high‐pressure induced phase transitions
Authors: Tikhomirova Galina , Babushkin Alexey 
Published: November 2006

AbstractComparative studies of high‐pressure effect on the resistivity of ammonium halides NH4X (X = F, Cl, Br) at the temperatures of 77 to 400 K are presented. High‐pressure phase transitions are found being apparent in a sharp change of the resistance by orders of magnitude at some critical pressures and a hysteresis typical for first‐order phase transitions. The critical pressure values correlate with the material density being approximately 40, 27 and 15 GPa for NH4F, NH4Cl and NH4Br, respectively. Relaxation times of resistivity at changing pressure are determined. The relaxation of resistivity obeys the exponential law at the pressures far enough from the critical ones; the relaxation times are tenths seconds to minutes. Near the critical pressures, the resistivity relaxation becomes highly non‐exponential; the time delay of hours to days appears before the phase transition (the resistance jump). (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of phenylboronic acid modified hydrogel affinity chips for high‐throughput mass spectrometric analysis of glycated proteins
Authors: Gontarev Sergey , Shmanai Vadim , Frey Simone K. , Kvach Maksim , Schweigert Florian J. 
Published: November 2006

AbstractThe complexity of the human plasma proteome is greatly increased by post‐translational modifications. Besides physiological modifications, pathological conditions such as diabetes are responsible for adding to this complexity by producing advanced glycation endproducts (AGEs). When searching for specific biomarkers it is a prerequisite to reduce this complexity prior to analysis. To do this, agarose hydrogel was used to create a high‐capacity affinity layer on the modified aluminum surface of MALDI (matrix‐assisted laser desorption/ionization) targets. 3‐Aminophenylboronic acid was immobilized via cyanogen bromide activation as a ligand for affinity sorption of glycated proteins, followed by their direct detection by MALDI. High protein capacity of prepared MALDI chips, efficient separation and low non‐specific protein binding were demonstrated. The results show that phenylboronic acid modified hydrogels are very suitable for creating affinity surfaces for the high‐throughput analysis of AGEs. Copyright © 2006 John Wiley & Sons, Ltd.
A simple purification protocol for the detection of peptide hormones in the hemolymph of individual insects by matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry
Authors: Fastner Sandy , Predel Reinhard , Kahnt Jörg , Schachtner Joachim , Wegener Christian 
Published: November 2006

AbstractThe endocrine system of insects is largely based on peptide hormones. Nevertheless, an unequivocal chemical demonstration of the occurence in the hemolymph (the ‘insect blood’) is still lacking for most if not all insect peptide hormones, although this is the only way to prove their hormonal status. Focusing on peptides released during ecdysis behavior of the tobacco hornworm Manduca sexta, we developed a purification protocol based on ultrafiltration and a single reversed‐phase high‐performance liquid chromatography (RP‐HPLC) step that for the first time allowed the mass spectrometric and chemical identification of a peptide hormone in the hemolymph of single specimens. Since this method is simple, relatively cheap and fast, it should be useful for routine endocrinological analyses and for monitoring peptide release during different physiological conditions and behaviors in insects. Copyright © 2006 John Wiley & Sons, Ltd.
Consensus control for a class of networks of dynamic agents
Authors: Xie Guangming , Wang Long 
Published: November 2006

AbstractIn this paper, the consensus problems for networks of dynamic agents are investigated. The agent dynamics is adopted as a typical point mass model based on the Newton's law. The average‐consensus problem is proposed for such class of networks, which includes two aspects, the agreement of the states of the agents and the convergence to zero of the speeds of the agents. A linear consensus protocol for such networks is established for solving such a consensus problem that includes two parts, a local speed feedback controller and the interactions from the finite neighbours. Two kinds of topology are discussed: one is fixed topology, the other is switching one. The convergence analysis is proved and the protocol performance is discussed as well. The simulation results are presented that are consistent with our theoretical results. Copyright © 2006 John Wiley & Sons, Ltd.
Studies on the role of phospholipids in the triglyceride cycle: I. Phospholipid synthesis in liver and plasma of ethionine‐treated rats
Authors: Olmsted C. A. 
Published: November 2006

AbstractA single administration ofdl‐ethionine to rats was found to initiate a rapid accumulation of triglyceride in the liver while plasma and liver phospholipid (PL) levels decreased. As measured by the incorporation of intravenous NaH2P32O4 at several time intervals after a single administration of ethionine, the drug decreased the specific activity (SA) of liver and plasma phospholipid phosphorus (PLP). At early time intervals after the injection of ethionine this occurred to a greater extent in the plasma than in the liver. Hence, the relative specific activity (RSA) of plasma to liver PLP was decreased initially by ethionine. As a measure of the exchange of PL between plasma and liver, this change in the RSA indicates decreased mobilization of PL from the liver to the plasma following ethionine inhibition of PL synthesis by the liver. Subsequently, the RSA increased, that is, an increased mobilization of PL occurred under conditions of fasting several hours after ethionine administration. Thus, it appeared that remobilization of liver PL tends to occur following the hepatic triglyceride accumulation brought about by inhibition of PL synthesis in the liver. However, remobilization of liver PL occurred also in male rats given ethionine and in fasted rats which did not show accumulation of hepatic triglyceride. These data suggest that phospholipid turnover and transport play an active role in the triglyceride cycle which is activated by fasting and during the recovery phase following ethionine administration.
Endocrine control of fat mobilization in the isolated fat cells of cold‐exposed rats
Authors: Therriault Donald G. , Hubbard Roger W. , Mellin Donald B. 
Published: November 2006

AbstractAdipose tissue in rats maintained at normal ambient temperature grows by a mixture of cell proliferation and lipid deposition in the early growth stage of the rat. In the mature rat, the tissue grows primarily by lipid deposition, mitotic activity being significantly decreased. When the rat is acclimated to 5 C, growth of adipose tissue is less than that of rats maintained at normal ambient temperature. Furthermore, growth of adipose tissue in the 5 C rat occurs through a mixture of cell proliferation and lipid deposition throughout the body weight range studied. The differences in tissue growth were taken into consideration in measuring the stimulatory effect of norepinephrine on lipolysis and reesterification of isolated fat cells. The results indicate that the cell size affects the lipolytic response; the larger the cell the less sensitive it is. Fat cells from cold‐acclimated rats are more sensitive to the lipolytic action of norepinephrine, independent of differences in cell size. On the other hand, reesterification is not affected by cell size, nor by exposure of the rat to cold
Stereospecific analysis of the major triglyceride species in the monounsaturated fraction of cocoa butter
Authors: Sampugna J. , Jensen R. G. 
Published: November 2006

AbstractA stereospecific analysis employing pancreatic lipase,Geotrichum candidum lipase and phospholipase A was applied to the monounsaturated triglyceride fraction of cocoa butter. Diacid triglycerides required additional analyses involving the gas liquid chromatographic determination of the proportions of digly ceride acetates produced by separately acetylating the α,α and α,β‐digly cerides obtained from aG. candidum digestion mixture. Results indicated that the major triacid triglyceride in cocoa butter wasrac glyceryl‐l‐palmitate‐2‐oleate‐3‐stearate. Approximately 5% of cocoa butter was comprised of triglycerides which were solely or predominantly of one enantiomer, containing oleic acid in the 3 position.
New sources of 9‐d‐hydroxy‐cis‐12‐octadecenoic acid
Authors: Powell R. G. , Kleiman R. , Smith C. R. 
Published: November 2006

Abstract9‐d‐Hydroxy‐cis‐12‐octadecenoic acid has been isolated from 3 seed oils of the family Apocynaceae:Holarrhena antidysenterica (73%),Nerium oleander (11%) andNerium indicum (8%). The known occurrence of this acid was previously limited to the genusStrophanthus (9–15%). A mixture of unusual tetra‐acid glycerides was isolated fromN. oleander oil by thin layer chromatography. Pancreatic lipase hydrolysis of the glyceride mixture showed that 9‐d‐acetoxy‐cis‐12‐octadecenoic acid is esterified exclusively at an α‐glycerol position and that normal fatty acids occupy the remaining 2 glycerol positions. A portion of the hydroxy acid inN. indicum oil was also acetylated, however, no acetate was found in eitherH. antidysenterica orStrophanthus hispidus oils.
Molecular species of phosphatidyl ethanolamine from egg yolk
Authors: Holub B. J. , Kuksis A. 
Published: November 2006

AbstractPhosphatidyl ethanolamine was isolated from total egg yolk lipids by preparative thin layer chromatography (TLC). The purified phosphatide contained 3% of the alkoxy derivative. It was degraded to diglycerides in the presence of purified sphingomyelin by phospholipase C fromClostridium welchii. The diglycerides were acetylated and resolved on the basis of unsaturation by argentation TLC. The fatty acid composition of the original phosphatidyl ethanolamine and the derived acetates was determined by gas chromatography, as was the molecular weight distribution of the diglyceride acetates. The placement of the fatty acids in the parent phosphatide was deduced by hydrolysis with phospholipase A fromCrotalus atrox, and in the acetates with pancreatic lipase. Some 33 major species of phosphatidyl ethanolamine were identified and compared to those for egg yolk lecithins.
Bio‐oxidation of linoleic acid via methylmalonyl‐CoA
Authors: Dupont Jacqueline , Mathias Melvin M. 
Published: November 2006

AbstractUnsaturated long‐chain fatty acids are oxidized more rapidly than are saturated fatty acids of similar chain length in intact animals and isolated mitochondria. Gamma‐oxidation of the 3‐dodecenoic acid intermediate in beta‐oxidation of oleate would yield propionate which is metabolized via methylmalonate.14C‐labeled fatty acids were administered to intact rats, muscle homogenates and lysed mitochondria. Methylmalonate, succinate and CO2 were isolated and14C determined. Incorporation of U‐14C‐linoleate into methylmalonate in vitro was 20 times greater than from U‐14C‐palmitate. Rats fed 20% corn oil grew more slowly on B12 deficient than B12 sufficient diets. Biotin and vitamin B12 deficiencies were found to decrease the in vivo metabolism of linoleate. These data suggest that one pathway of linoleate oxidation has methylmalonate as an intermediate.
A comparative study of gangliosides from the brains of various species
Authors: Schengrund C. ‐L. , Garrigan O. W. 
Published: November 2006

AbstractA comparison is made of the sialic acid and hexose content of crude gangliosides from the brains of 13 species, including mammals, a bird, and amphibian, a reptile and fish. The sialic acid content is relatively constant from species to species. Gangliosides are less abundant in tissues other than the brain. Four species (cat, dog, pig and sheep) were selected for the determination of their major ganglioside subfractions. The ganglioside subfractions were isolated (after extraction and partition dialysis) using descending thin layer chromatography. The population of ganglioside molecules varied from species to species. From dog and sheep a mono‐, a di‐ and a trisialoganglioside were obtained; from cat a mono‐, a di‐ and two trisialogangliosides; and from pig a mono‐ and two disialogangliosides. Each ganglioside subfraction was found to contain glucose, galactose and galactosamine in the ratio of approximately 1∶2∶1. The fatty acid moieties consisted of more than 80% stearic acid with lesser amounts of arachidic, palmitic and behenic acid. Sphingosine analyses indicated ratios of sphingosine to icosisphingosine of 7∶3 for the monosialo‐, 1∶1 for the disialo‐ and 3∶7 for the trisialogangliosides.
Essential fatty acid‐deficient rats: II. On the fatty acid composition of partially hydrogenated arachis, soybean and herring oils and of normal, refined arachis oil
Authors: Hølmer G. , Aaes‐Jørgensen E. 
Published: November 2006

AbstractThe fatty acid composition of partially hydrogenated arachis (HAO), partially hydrogenated soybean (HSO) and partially hydrogenated herring (HHO) oils and of a normal, refined arachis oil (AO) was studied in detail by means of direct gas liquid chromatography, ultraviolet and infrared spectrophotometry and by thin layer chromatography fractionation on silver nitrate‐silica gel plates followed by gas liquid chromatography. It was shown that the partially hydrogenated oils all contained fatty acids withtrans double bonds. In the plant oils, thetrans acids were present mainly as elaidic acid. The HHO showed an almost equal distribution betweentrans 18∶1 ω9,trans 20∶1 ω>9 andtrans 22∶1 ω>9. Sometrans configuration was also found in the C20‐and C22‐dienes and trienes of the HHO. In all the oils, conjugated fatty acids were present in minor amounts only (<0.5%). Special attention was given to the ω‐acids known to be of specific nutritional value. The HSO contained about 32% linoleic acid, whereas the content ofcis, trans+trans, cis andtrans, trans octadecadienoic isomers was 1.7% and 0.5%, respectively. The amount of linoleic acid in the HSO was even higher than that of AO (29%). The HAO contained only 0.8% 18∶2 ω6 (linoleic acid). Further, two 18∶2 fatty acids with ω>6, acis, cis and atrans, trans isomer, were present in small amounts. The HHO contained 0.5% 18∶2 ω6 (linoleic acid). Isomers of 18∶2 ω>6 were also found in the HHO. They may be hydrogenation products of higher unsaturated C18‐acids orginally present. All the C20‐ and C22‐dienes and trienes were shown to have an ω‐chain greater than 6. Fatty acids with ω6‐structure were not formed during partial hydrogenation of the oils studied.
Differential incorporation of acetate and glucose in maturing douglas fir seeds
Authors: Te Ching May , Fang S. C. 
Published: November 2006

AbstractIn order to discern the synthetic pathways of lipids in coniferous seeds, decoated maturing Douglas fir seeds were incubated with 2‐14C‐acetate and ul‐14C‐glucose for 3 hr in phosphate buffer at pH 6.0. About 52% of incorporated acetate was found in lipids, but only 9% of the absorbed glucose was converted to lipids. Distribution of incorporated radioactivity in lipid classes was similar for both substrates, 45% in polar lipids, 22% in diglycerides, 15% in triglcerides, 7% in sterol esters, 4% in each of fatty acids and monoglycerides, and 3% in sterols. High specific activity was found in free fatty acids, diglycerides, monoglycerides and polar lipids indicating a rapid turnover of the intermediates for reserve triglycerides and structural polar lipids. Degradation analyses showed that 50% of incorporated acetate and glucose in lipids were in fatty acid moiety. Acetate contributed more in sterols and other unsaponifiables than in glycerol, and the reverse was true for glucose. All the data indicated that acetate is the direct precursor of fatty acids and sterols. General synthetic pathways prevail in fir seeds. Methods for complete analysis of chemical and radio‐chemical composition were presented and results discussed.