bluuebunny/crossref_metadata_2025_split huggingface dataset:
An efficient solubilization buffer for plant proteins focused in immobilized pH gradients
Authors: Méchin Valérie , Consoli Luciano , Le Guilloux Martine , Damerval Catherine 
Published: July 2003

AbstractThe solubilization of a large array of proteins before electrophoresis itself is a very critical point for proteomic analyses. We compared the efficiency of several different solubilization buffers. From this work, we defined a very efficient solubilization buffer, including two chaotropes, two reducing agents (R2), two detergents (D2), and two kinds of carrier ampholytes in combination. This so‐called R2D2 buffer (5 M urea, 2 M thiourea, 2% 3‐[(3‐cholamidopropyl) dimethyl‐ammonio]‐1‐propane‐sulfonate, 2% N‐decyl‐N,N‐dimethyl‐3‐ammonio‐1‐propane‐sulfonate, 20 mM dithiothreitol, 5 mM Tris(2‐carboxyethyl) phosphine, 0.5% carrier ampholytes 4–6.5, 0.25% carrier ampholytes 3‐10) proved to be very efficient for a large range of different samples and allowed us to obtain two‐dimensional gels of high resolution and quality.
Enhanced resolution of glycosylphosphatidylinositol‐anchored and transmembrane proteins from the lipid‐rich myelin membrane by two‐dimensional gel electrophoresis
Authors: Taylor Christopher M. , Pfeiffer Steven E. 
Published: July 2003

AbstractTwo‐dimensional gel electrophoresis (2‐DE) has become a powerful and widely used technique for proteomic analyses. However, the limited ability of 2‐DE to resolve transmembrane and glycosylphosphatidylinositol (GPI)‐anchored proteins has slowed the identification of proteins from membrane‐rich biological samples. Myelin is an unusually lipid‐rich membrane with relatively few major proteins but many quantitatively minor proteins, most of which have an unknown identity and/or function. The goal of this study was to identify the optimal conditions of 2‐DE for the separation of myelin proteins. We have identified two detergents, the nonionic n‐dodecyl β‐D‐maltoside and the zwitterionic amidosulfobetaine ASB‐14, that are more effective in solubilizing myelin proteins than the commonly used zwitterionic detergent 3‐[(3‐cholamidopropyl)‐ dimethylammonio]‐1‐propanesulfonate (CHAPS). These detergents significantly enhance the solubility of both transmembrane (e.g., the highly hydrophobic and multiply acylated myelin proteolipid protein) and GPI‐anchored (e.g., contactin and neuronal cell adhesion molecule) myelin proteins and enable their resolution by 2‐DE. We conclude that these detergents are effective tools for the 2‐DE analysis of myelin, and that they may be more generally useful for the analysis of membrane‐rich biological samples.
Unmatched masses in peptide mass fingerprints caused by cross‐contamination: An updated statistical result
Authors: Ding Qinxue , Xiao Lin , Xiong Shaoxiang , Jia Yufeng , Que Haiping , Guo Yaojun , Liu Shaojun 
Published: July 2003

AbstractUnmatched masses are often observed in the experimental peptide mass spectra when database searching is performed with the ProFound program. Comparison between theoretical and experimental mass spectra of standard proteins shows that contamination accounts for most of the unmatched masses. In this retrospective analysis, the top 100 most probable contaminating masses, as listed in order of their probability, are statistically filtered out from 118 different experimental peptide mass fingerprinting (PMF) maps. Most of the interfering masses originate from trypsin autolysis and human keratins. Subtraction of known contaminants from raw data and using cleaner masses for searching can enhance protein identification by PMF.
Innate differences in protein expression in the nucleus accumbens and hippocampus of inbred alcohol‐preferring and ‐nonpreferring rats
Authors: Witzmann Frank A. , Li Junyu , Strother Wendy N. , McBride William J. , Hunter Lawrence , Crabb David W. , Lumeng Lawrence , Li Ting‐Kai 
Published: July 2003

AbstractTwo‐dimensional gel electrophoresis (2‐DE) was used to separate protein samples solubilized from the nucleus accumbens and hippocampus of alcohol‐naïve, adult, male inbred alcohol‐preferring (iP) and alcohol‐nonpreferring (iNP) rats. Several protein spots were excised from the gel, destained, digested with trypsin, and analyzed by mass spectrometry. In the hippocampus, 1629 protein spots were matched to the reference pattern, and in the nucleus accumbens, 1390 protein spots were matched. Approximately 70 proteins were identified in both regions. In the hippocampus, only 8 of the 1629 matched protein spots differed in abundance between the iP and iNP rats. In the nucleus accumbens, 32 of the 1390 matched protein spots differed in abundance between the iP and iNP rats. In the hippocampus, the abundances of all 8 proteins were higher in the iNP than iP rat. In the nucleus accumbens, the abundances of 31 of 32 proteins were higher in the iNP than iP rat. In the hippocampus, only 2 of the 8 proteins that differed could be identified, whereas in the nucleus accumbens 21 of the 32 proteins that differed were identified. Higher abundances of cellular retinoic acid‐binding protein 1 and a calmodulin‐dependent protein kinase (both of which are involved in cellular signaling pathways) were found in both regions of the iNP than iP rat. In the nucleus accumbens, additional differences in the abundances of proteins involved in (i) metabolism (e.g., calpain, parkin, glucokinase, apolipoprotein E, sorbitol dehydrogenase), (ii) cyto‐skeletal and intracellular protein transport (e.g., β‐actin), (iii) molecular chaperoning (e.g., grp 78, hsc70, hsc 60, grp75, prohibitin), (iv) cellular signaling pathways (e.g., protein kinase C‐binding protein), (v) synaptic function (e.g., complexin I, γ‐enolase, syndapin IIbb), (vi) reduction of oxidative stress (thioredoxin peroxidase), and (vii) growth and differentiation (hippocampal cholinergic neurostimulating peptide) were found. The results of this study indicate that selective breeding for disparate alcohol drinking behaviors produced innate alterations in the expression of several proteins that could influence neuronal function within the nucleus accumbens and hippocampus.
Study of human laryngeal muscle protein using two‐dimensional electrophoresis and mass spectrometry
Authors: Li Zhao‐Bo , Lehar Mohamed , Braga Natasha , Westra William , Liu Li‐Hong , Flint Paul W. 
Published: July 2003

AbstractProteomic analysis was performed to construct a protein database for human laryngeal muscle. Thyroarytenoid (TA) muscle specimens were obtained from six post mortem cases within 24 h of death. Isoelectric focusing was performed by using immobilized pH gradient strips followed by 12% sodium dodecyl sulfate‐polyacrylamide gel electrophoresis. Silver stained gels were then analyzed using PDQuest software to locate, quantify and match spots. Proteins were identified by matrix‐assisted laser desorption/ionization‐mass spectrometry on the basis of peptide mass fingerprinting following in‐gel digestion with trypsin. Comparison of protein distribution between broad and narrow pH range gels demonstrated that 75% of all protein spots from human TA muscle were located within the pH range 5–8, and between mass 15–120 kDa. Based on peptide mass fingerprinting, 75 proteins were identified and classified into six functional groups. These include membrane proteins (8.5%), cytoskeletal and myofibrillar proteins (14.6%), energy production proteins (28%), proteins associated with stress responses (8.5%), and protein associated with transcription regulation (10.9%). Approximately one‐third (29%) were categorized as “other proteins”. This data provides an initial reference map for comparative studies of protein expression in human and laryngeal muscle. Further development of this database will provide a valuable resource for molecular analysis of normal and pathologic conditions affecting human striated muscle.
The Proteomics Standards Initiative
Authors: Orchard Sandra , Hermjakob Henning , Apweiler Rolf 
Published: July 2003

AbstractThe Proteomics Standards Initiative (PSI) aims to define community standards for data representation in proteomics and to facilitate data comparison, exchange and verification. Progress has been made in the development of common standards for data exchange in the fields of both mass spectrometry and protein‐protein interaction. A proteomics‐specific extension is being created for the emerging American Society for Tests and Measurements mass spectrometry standard, which will be supported by manufacturers of both hardware and software. A data model for proteomics experimentation is under development and discussions on a public repository for published proteomics data are underway. The Protein‐Protein Interactions group expects to publish the Level 1 PSI data exchange format for protein‐protein interactions soon and discussions as to the content of Level 2 have been initiated.
Interfacial fracture toughness between glassy polymer networks
Authors: Perez‐Salas U. , Briber R. M. , Rafailovich M. H. , Sokolov J. 
Published: July 2003

AbstractThe interfacial fracture energy, Gc, between glassy crosslinked polystyrene samples was studied with the symmetric double‐cantilever beam test. Compression‐molded polystyrene slabs were crosslinked by γ irradiation in vacuo. The fracture samples were prepared by the welding of two crosslinked polystyrene slabs under contact pressure for 1 h at 150 °C, which was above the glass‐transition temperature for polystyrene (≅104 °C). The fracture toughness tests were performed at room temperature. The interfacial fracture energy was studied as a function of the crosslink density of the slabs. It was found that the interfacial fracture energy decreased with increasing crosslink density. A least‐squares fit of the data showed that the interfacial fracture energy scaled as N, where Nc is the weight‐average chain length between crosslinks (in number of monomer units). A comparison with the predictions made by different models on weak interfaces was made. It was found that if the loops of the network were identified as the connectors responsible for adhesion at the glassy network‐network interfaces, the model by Xu et al. predicted that Gc would scale as N, consistent with the trends in the data. Using the expression for Gc from this model to fit the data the value for the static friction constant per monomer for polystyrene was found to be fmono = 3.5 ± 0.7 × 10−12 N/monomer, in good agreement with the values found in the literature. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1902–1908, 2003
Viscoelastic relaxation mechanisms of conventional polypropylene toughened by a plastomer
Authors: Prieto Óscar , Pereña José M. , Benavente Rosario , Pérez Ernesto , Cerrada María L. 
Published: July 2003

AbstractPlastomers are new alternatives that provide a higher impact strength in polypropylene synthesized by conventional methods. This study presents an analysis of the structure and thermal characterization of two sets of polypropylene/plastomer blends. The difference between the two polypropylene samples is their molecular weight. With the structural knowledge obtained, a comprehensive analysis of the different relaxation processes has been performed. Neither component is miscible. The area under the loss tangent curves provides preliminary information about how the toughness is enhanced with this type of impact modifier. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1878–1888, 2003
Enhanced soil sorption of methidathion using sewage sludge and surfactants
Authors: Sánchez Lourdes , Romero Esperanza , Sánchez‐Rasero Francisco , Dios Gonzalo , Peña Aránzazu 
Published: July 2003

AbstractBatch experiments were carried out to examine the partitioning of an organophosphorus insecticide, methidathion, in non‐amended agricultural soil and soil amended with urban sewage sludge and/or different types of surfactant. Kinetic data showed that sewage sludge significantly reduced adsorption rate, whereas amendment of the soil with the cationic surfactant tetradecyltrimethylammonium bromide (TDTMA) at 10× CMC (critical micellar concentration) increased the adsorption rate by a factor of 10. The adsorption isotherms were evaluated using the Freundlich model. The soil adsorption capacity for methidathion was enhanced by amendment with sewage sludge and even more significantly with TDTMA at 10× CMC or combined with sewage sludge. TDTMA conferred a high hydrophobic character to the soil, enhancing the adsorption capacity of the rather hydrophobic methidathion. The amendment of soil both with sewage sludge and TDTMA combines the increased hydrophobicity with a higher surfactant retention by organic matter, due to an increase in cation exchange capacity, which promotes even more the adsorption capacity for the insecticide. An anionic surfactant, linear alkylbenzene sulfonate, and the non‐ionic Tween 80 only induced a slight modification in the kinetics and adsorption of methidathion. Copyright © 2003 Society of Chemical Industry
Insecticide resistance in Egyptian populations of the cotton whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae)
Authors: Kady Hafez El , Devine Gregor J 
Published: July 2003

AbstractThree collections of Bemisia tabaci were taken from cotton and vegetable crops at the beginning of the growing season in Egypt. These displayed marked resistance to the carbamates carbosulfan (ca 20‐ to 50‐fold) and aldicarb (ca 40‐ to 80‐fold) and moderate resistance to the pyrethroids cypermethrin (ca 10‐ to 30‐fold) and lambda‐cyhalothrin (ca 10‐ to 25‐fold). They displayed no resistance to the organophosphates profenofos and pirimiphos‐methyl, or to imidacloprid. Another population, collected at the end of the growing season, differed markedly in its response. In this population, resistance to carbosulfan remained high (ca 40‐fold), resistance to profenofos and cypermethrin was increased (ca 20‐ and 50‐fold respectively) and a slight resistance to imidacloprid was detected (ca 6‐fold). Resistance to cypermethrin and profenofos was shown to be similar among adults and nymphs. Irrespective of collection date, none of the populations showed resistance to pyriproxyfen. These Egyptian populations were compared with two representative Israeli populations. The differences between their resistance profiles is discussed in terms of their collection date, their geographical proximity and the patterns of insecticide use at their sites of collection. Copyright © 2003 Society of Chemical Industry
Isolation and in vitro and in vivo activity against Phytophthora capsici and Colletotrichum orbiculare of phenazine‐1‐carboxylic acid from Pseudomonas aeruginosa strain GC‐B26
Authors: Lee Jung Yeop , Moon Surk Sik , Hwang Byung Kook 
Published: July 2003

AbstractThe bacterial strain GC‐B26, which showed strong antifungal and anti‐oomycete activity against some plant pathogens, was isolated from a grassland soil in Korea. Based on morphological, physiological and biochemical characteristics, GC‐B26 was identical to Pseudomonas aeruginosa (Schroeter) Migula. The antibiotic G26A, active against Phytophthora capsici Leonian and Colletotrichum orbiculare (Berk & Mont) van Arx, was isolated from the culture filtrates of Ps aeruginosa strain GC‐B26 using various chromatographic procedures. The EI mass and UV spectral results indicated that G26A is an analogue of phenazines, having molecular formula C13H8N2O2 (M+, m/z 224.0664). On the basis of NMR spectral data, G26A was confirmed as phenazine‐1‐carboxylic acid. C orbiculare, P capsici and Pythium ultimum Trow were most sensitive to G26A, with MIC values of approximately 5 µg ml−1. However, no antimicrobial activity was found against yeasts and bacteria, even at a concentration of over 100 µg ml−1. Treatment with the antibiotic gave highly significant protective activity against the development of Phytophthora disease on pepper and anthracnose on cucumber plants. The disease control efficacy was only slightly less than that of the commercial fungicides metalaxyl and chlorothalonil. Copyright © 2003 Society of Chemical Industry
The cyclization transformation of the sulfonylurea herbicide flupyrsulfuron in the soil of winter wheat crops
Authors: Rouchaud Jean , Neus Olivier , Moulard Claude 
Published: July 2003

AbstractThe synthesis of 1‐(4,6‐dimethoxypyrimidine‐2‐yl)‐7‐trifluoromethyl‐1,2,3,4‐tetrahydropyrido[2,3‐d]pyrimidin‐2,4‐dione has been carried out in such a way that the dimethoxypyrimidine substituent was unambiguously in position 1 of the pyrido[2,3‐d]pyrimidine ring. This regioisomer was obtained by cyclization with phosgene of 2‐(4,6‐dimethoxypyrimidin‐2‐ylamino)‐6‐trifluoromethylnicotinamide which had previously been ionized with sodium hydride. It was shown to be identical to the metabolite generated in the soil of winter wheat crops treated previously with the sulfonylurea herbicide flupyrsulfuron‐methyl [(methyl 2‐(4,6‐dimethoxypyrimidin‐2‐ylcarbamoylsulfamoyl)‐6‐trifluoromethylnicotinate]. The position of the dimethoxypyrimidine substituent had not previously been assigned unambiguously to positions 1 or 3 of the pyrido[2,3‐d]pyrimidine ring. The regioisomer was also identical to the cyclization compound generated chemically from flupyrsulfuron in a sterile water buffer at pH 9. The metabolism pathways of flupyrsulfuron in soil are discussed in the light these structure determinations and compared with the soil metabolism pathways frequently observed with other sulfonylurea herbicides. Copyright © 2003 Society of Chemical Industry
Evaluation of chemical and integrated strategies as alternatives to methyl bromide for the control of root‐knot nematodes in Greece
Authors: Giannakou Ioannis O , Karpouzas Dimitrios G 
Published: July 2003

AbstractCurrent environmental awareness has led to a greater demand for alternative nematode control strategies. Three field experiments were established to compare management tactics on cucumber in commercial greenhouses naturally infested with root‐knot nematodes (Meloidogyne spp). Cucumber rootstocks which have shown resistance to soil‐borne diseases were tested to reveal any resistance/tolerance to root‐knot nematodes, and integration of these rootstocks with nematicides was investigated. Metham‐sodium and 1,3‐dichloropropene (1,3‐D) provided good control of nematode populations when their application was followed by the application of a non‐fumigant nematicide such as cadusafos or oxamyl. Neither fumigant could provide season‐long control of nematode populations, and a further application of cadusafos was required for satisfactory control. The efficacy of metham‐sodium was significantly increased when injected into soil in comparison with its application through the drip irrigation system. The use of rootstocks resistant to soil‐borne fungal pathogens used together with chemical means of nematode control provided promising results for their further use in integrated strategies as alternatives to methyl bromide. However, the latter was the superior treatment for the control of root‐knot nematodes in soil infested with residues of galled roots. Dazomet, metham‐sodium nor the non‐fumigant nematicides oxamyl and fenamiphos could reduce nematode population as efficiently as methyl bromide. None of the chemicals tested except methyl bromide could enter galled roots and kill surviving nematodes. Copyright © 2003 Society of Chemical Industry
Spatial variability of atrazine dissipation in an allophanic soil
Authors: Müller Karin , Smith Roger E , James Trevor K , Holland Patrick T , Rahman Anis 
Published: July 2003

AbstractThe small‐scale variability (0.5 m) of atrazine (6‐chloro‐N2‐ethyl‐N4‐isopropyl‐1,3,5‐triazine‐2,4‐diamine) concentrations and soil water contents in a volcanic silt loam soil (Haplic Andosol, FAO system) was studied in an area of 0.1 ha. Descriptive and spatial statistics were used to analyse the data. On average we recovered 102% of the applied atrazine 2 h after the herbicide application (CV = 35%). An increase in the CV of the concentrations with depth could be ascribed to a combination of extrinsic and intrinsic factors. Both variables, atrazine concentrations and soil water content, showed a high horizontal variability. The semivariograms of the atrazine concentrations exhibited the pure nugget effect, no pattern could be determined along the 15.5‐m long transects on any of the seven sampling days over a 55‐day period. Soil water content had a weak spatial autocorrelation with a range of 6–10 m. The dissipation of atrazine analysed using a high vertical sampling resolution of 0.02 m to 0.2 m showed that 70% of the applied atrazine persisted in the upper 0.02‐m layer of the soil for 12 days. After 55 days and 410 mm of rainfall the centre of the pesticide mass was still at a soil depth of 0.021 m. The special characteristics of the soil (high organic carbon content, allophanic clay) had a strong influence on atrazine sorption and mobility. The mass recovery after 55 days was low. The laboratory degradation rate for atrazine, determined in a complementary incubation study and corrected for the actual field temperature using the Arrhenius equation, only accounted for about 35% of the losses that occurred in the field. Results suggest field degradation rates to be more changeable in time and much faster than under controlled conditions. Preferential flow is discussed as a component of the field transport process. Copyright © 2003 Society of Chemical Industry
Effects of a juvenile hormone analog, pyriproxyfen, on Thrips tabaci (Thysanoptera: Thripidae)
Authors: Liu Tong‐Xian 
Published: July 2003

AbstractEffects of a juvenile hormone analog, pyriproxyfen, on various developmental stadia of the onion thrips, Thrips tabaci Lindeman, were determined on cabbage leaves in the laboratory. Pyriproxyfen was applied at 0.064 or 0.128 g AI liter−1 on leaves (residual contact–ingestion), thrips (direct contact) and leaf–thrips (residue contact–ingestion–direct contact). Pyriproxyfen did not have any significant lethal effects on thrips pupae in any treatment. Lethal effects on thrips larvae varied depending on application method and dosage. In the leaf and the leaf–thrips treatments, few larvae and pre‐pupae molted to the next stage, and none developed to adults. In contrast, in the thrips‐only treatment, pyriproxyfen did not show any significant lethal effects. The developmental times of larvae and pre‐pupae were prolonged when larvae were treated with pyriproxyfen, and those of pre‐pupae and pupae were shortened when pre‐pupae and pupae were treated. The longevity and survival rates of thrips adults were generally shorter when they contacted and ingested pyriproxyfen‐treated leaves than those in water control. Significantly fewer progeny (0.22–1.15 larvae per female) were produced by females that had fed on and been in contact with the pyriproxyfen‐treated leaves than by those in the water control (11.94 larvae per female). However, the number of progeny produced by the thrips females increased significantly (3.32–7.28 larvae per female) when the females were transferred to untreated leaves after feeding on treated leaves for 5 days; the daily larval hatching pattern was similar to those in water control, indicating that female adults were able to produce viable eggs when untreated food was offered. Copyright © 2003 Society of Chemical Industry