bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of the HUPO Brain Proteome reference samples using 2‐D DIGE and 2‐D LC‐MS/MS
Authors: Fröhlich Thomas , Helmstetter Derrick , Zobawa Monica , Crecelius Anna C. , Arzberger Thomas , Kretzschmar Hans A. , Arnold Georg J. 
Published: August 2006

AbstractWithin the Human Proteome Organization (HUPO) Brain Proteome Project, a pilot study was launched with reference samples shipped to nine international laboratories (see Hamacher et al., this Special Issue) to evaluate different proteome approaches in neuroscience and to build up a first version of a brain protein database. One part of the study addresses quantitative proteome alterations between three developmental stages (embryonic day 16; postnatal day 7; 8 weeks) of mouse brains. Five brains per stage were differentially analyzed by 2‐D DIGE using internal standardization and overlapping pH gradients (pH 4–7 and 6–9). In total, 214 protein spots showing stage‐dependent intensity alterations (>two‐fold) were detected, 56 of which were identified. Several of them, e.g. members of the dihydropyrimidinase family, are known to be associated with brain development. To feed the HUPO BPP brain protein database, a robust 2‐D LC‐MS/MS method was applied to murine postnatal day 7 and human post‐mortem brain samples. Using MASCOT and the IPI database, 350 human and 481 mouse proteins could be identified by at least two different peptides. The data are accessible through the PRIDE database (http://www.ebi.ac.uk/pride/).
Examination of 2‐DE in the Human Proteome Organisation Brain Proteome Project pilot studies with the new RAIN gel matching technique
Authors: Dowsey Andrew W. , English Jane , Pennington Kyla , Cotter David , Stuehler Kai , Marcus Katrin , Meyer Helmut E. , Dunn Michael J. , Yang Guang‐Zhong 
Published: August 2006

AbstractThe Human Proteome Organisation (HUPO) Brain Proteome Project (BPP) pilot studies have generated over 200 2‐D gels from eight participating laboratories. This data includes 67 single‐channel and 60 DIGE gels comparing 30 whole frozen C57/BL6 female mouse brains, ten each at embryonic day 16, postnatal day 7 (juvenile) and postnatal day 54–56 (adult); and ten single‐channel and three DIGE gels comparing human epilepsy surgery of the temporal front lobe with a corresponding post‐mortem specimen. The samples were generated centrally and distributed to the participating laboratories, but otherwise no restrictions were placed on sample preparation, running and staining protocols, nor on the 2‐D gel analysis packages used. Spots were characterised by MS and the annotated gel images published on a ProteinScape web server. In order to examine the resultant differential expression and protein identifications, we have reprocessed a large subset of the gels using the newly developed RAIN (Robust Automated Image Normalisation) 2‐D gel matching algorithm. Traditional approaches use symbolic representation of spots at the very early stages of the analysis, which introduces persistent errors due to inaccuracies in spot modelling and matching. With RAIN, image intensity distributions, rather than selected features, are used, where smooth geometric deformation and expression bias are modelled using multi‐resolution image registration and bias‐field correction. The method includes a new approach of volume‐invariant warping which ensures the volume of protein expression under transformation is preserved. An image‐based statistical expression analysis phase is then proposed, where small insignificant expression changes over one gel pair can be revealed when reinforced by the same consistent changes in others. Results of the proposed method as applied to the HUPO BPP data show significant intra‐laboratory improvements in matching accuracy over a previous state‐of‐the‐art technique, Multi‐resolution Image Registration (MIR), and the commercial Progenesis PG240 package.
Kinetic and mechanistic studies on sulfamate esters: models of enzyme inhibitors
Authors: McCaw Cheryl J. A. , Spillane William J. 
Published: August 2006

AbstractMany compounds containing a sulfamate moiety, such as NH2SO2O are now known to be medicinally important. However, very little is known about their mechanisms of reaction even under non‐biological conditions. In this work the various types of elimination mechanisms that may occur have been probed by studying the kinetics of the reactions of model sulfamate substrates with amines (bases) that act as models for the enzymes involved. The principal mechanistic tool employed has been Brönsted plots and both ‘normal’ rectilinear and two types of biphasic plots have been found for the decomposition of the esters in acetonitrile (ACN). The mechanisms operating are seen as being of the E2 and E1cB types. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis, characterization, and electrical properties of a diazodiphenylene‐bridged Cu–phthalocyanine polymer
Authors: Alkan Cemil , Aras Leyla , Gündüz Güngör 
Published: August 2006

AbstractA diazodiphenylene‐bridged Cu–phthalocyanine polymer was synthesized from the diazonium salt of bensidine and the Cu(II) 1,8,15,22‐tetraaminophthalocyanine complex and characterized with Fourier transform infrared, ultraviolet–visible spectroscopy, and elemental analysis. The polymer was partially soluble in organic solvents such as dimethylformamide and tetrahydrofuran. The molecular weight of the soluble part of the polymer was investigated with ebullioscopy and viscosimetry methods in tetrahydrofuran. Both methods showed that the molecular weight of the polymer was much larger than that of the complex. The conductivity of the samples was measured with a four‐prop conductivity measuring device. Iodine and hydrogen chloride were doped to the polymer, and an increase of about 104 S cm−1 in the electrical conductivity was observed. The cyclic voltammogram of the diazodiphenylene‐bridged Cu–phthalocyanine polymer in contact with a LiClO4 electrolyte exhibited two reductions and two reoxidations with high reversibility and electrochemical stability. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5692–5698, 2006
New environmentally responsive fluorescent N‐isopropylacrylamide copolymer and its application to DNA sensing
Authors: Yang Chang‐Chung , Tian Yanqing , Jen Alex K.‐Y. , Chen Wen‐Chang 
Published: August 2006

AbstractWe report two novel multifunctional copolymers consisting of a temperature‐responsive poly(N‐isopropylacrylamide) (PNIPAA) segment and a fluorescent fluorene‐containing acrylic polymer segment with pH responsiveness and/or DNA‐sensing ability. The functional acrylic monomer with a fluorene dimer side group substituted with amino units was synthesized first. Then, it was copolymerized with N‐isopropylacrylamide to result in a new water‐soluble, fluorescent PNIPAA copolymer (P1). The fluorescent properties of P1 under neutral and acidic conditions did not change with the temperature. However, significant variation was observed under basic conditions. The protonation of the amino moiety at a low pH improved the solubility and prevented aggregation for fluorescence quenching, but not under the basic conditions. Although aggregation of the fluorene units was significant at room temperature under basic conditions, the aggregation was resolved at a temperature above the lower critical solution temperature. These findings indicated the pH‐ and temperature‐responsive characteristics of P1. Moreover, after the amino groups were quaternized, the obtained polymer could be used as a biosensor because the fluorescence intensity was quenched with the addition of DNA. This study demonstrates that multifunctional materials with pH‐ and temperature‐sensing characteristics and biological molecules could be realized by the incorporation of a functional fluorene‐containing moiety with PNIPAA. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5495–5504, 2006
ABC‐type hetero‐arm star terpolymers through “Click” chemistry
Authors: Altintas Ozcan , Hizal Gurkan , Tunca Umit 
Published: August 2006

AbstractHetero‐arm star ABC‐type terpolymers, poly(methyl methacrylate)‐polystyrene‐poly(tert‐butyl acrylate) (PMMA‐PS‐PtBA) and PMMA‐PS‐poly(ethylene glycol) (PEG), were prepared by using “Click” chemistry strategy. For this, first, PMMA‐b‐PS with alkyne functional group at the junction point was obtained from successive atom transfer radical polymerization (ATRP) and nitroxide‐mediated radical polymerization (NMP) routes. Furthermore, PtBA obtained from ATRP of tBA and commercially available monohydroxyl PEG were efficiently converted to the azide end‐functionalized polymers. As a second step, the alkyne and azide functional polymers were reacted to give the hetero‐arm star polymers in the presence of CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) in DMF at room temperature for 24 h. The hetero‐arm star polymers were characterized by 1H NMR, GPC, and DSC. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5699–5707, 2006
Effect of excess halide on the palladium‐catalyzed insertion‐triggered radical copolymerization of methyl acrylate and 1‐hexene
Authors: Albéniz Ana C. , Espinet Pablo , López‐Fernández Raquel 
Published: August 2006

Abstract[Pd2(μ‐Cl)2(C6F5)2(tht)2] (1) is a very efficient initiator of the radical polymerization of methyl acrylate, but it is not active in the polymerization of methyl methacrylate or in the copolymerization with 1‐hexene. The addition of an excess of NBu4Cl to solutions of [Pd2(μ‐Cl)2(C6F5)2(tht)2] (1) provides an initiator system that copolymerizes methyl acrylate and 1‐hexene by an insertion‐triggered radical mechanism. Random copolymers are obtained with 11% incorporation of 1‐hexene in moderate yields (about 35%). Studies of the decomposition products obtained after the first insertion of methyl acrylate in the PdC6F5 bond of 1 show that the addition of excess halide in the presence of monomer favors the homolytic cleavage of the PdC bond, and the generation of the radicals that are active species in the polymerization, versus alternative evolution pathways. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5682–5691, 2006
Reversible‐addition fragmentation chain transfer radical emulsion polymerization by a nanoprecipitation process
Authors: Szkurhan Andrea R. , Kasahara Takahito , Georges Michael K. 
Published: August 2006

AbstractPolymerizations of styrene under emulsion reversible‐addition fragmentation chain transfer polymerization conditions are reported. Using a recently developed nanoprecipitaiton process, emulsion particles were formed by the precipitation of an acetone solution of a macroRAFT agent into an aqueous solution of poly(vinyl alcohol). The particles were then swollen with monomer and subsequently polymerized. Emulsion polymerizations were performed at 65 and 75 °C in which either KPS, BPO, or a combination of both was used as an initiating source. Reactions were also performed at temperatures over 100 °C in which the thermal initiation of styrene was used as an initiating source. In all cases, the polymerizations proceeded in a living manner, yielding polymers that showed an incremental increase in molecular weight with time and had narrow molecular weight distributions. Plots of number‐ average molecular weight versus conversion were linear, indicating a controlled polymerization. The resulting latices were colloidally stable and gave particle size distributions with a typical average particle diameter in the 150 nm range. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5708–5718, 2006
α,α‐Dibromotoluene as a monomer for poly (substituted methylene) synthesis: Magnesium‐mediated polycondensation of α,α‐dibromotoluene and magnesium/copper‐mediated copolycondensation of α,α‐dibromotoluene with 1,6‐dibromohexane
Authors: Ihara Eiji , Wake Takao , Mokume Naoki , Itoh Tomomichi , Inoue Kenzo 
Published: August 2006

Abstractα,α‐Dibromotoluene 1 was found to be polymerized by the reaction with excess Mg to give poly(phenylmethylene)s 2, whose main chains were partially dehydrogenated to carbon–carbon double bonds (CC). The CCs in 2 can be brominated by treatment with Br2. The polymerization mechanism was presumed to include the formation of Grignard reagents of various species with benzylic CBr bonds and the nucleophilic attacks of the Grignard reagents to various compounds with benzylic CBr bonds. Copolymerization of 1 with dichlorodimethylsilane successfully proceeded. Mg/Cu‐mediated copolycondensation of 1 with 1,6‐dibromohexane proceeded to give polymers that have similar compositions to those of random copolymers of ethylene and styrene. © 2006Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5661–5671, 2006
Synthesis and characterization of a new disubstituted polyacetylene containing indolylazo moieties in side chains
Authors: Li Zhen , Li Qianqian , Qin Anjun , Dong Yongqiang , Lam Jacky W. Y. , Dong Yuping , Ye Cheng , Qin Jingui , Tang Ben Zhong 
Published: August 2006

AbstractA new disubstituted polyacetylene with indolylazo moieties in its side chains (9) was synthesized by a post functionalization strategy, which was difficult, or perhaps impossible, to obtain from the direct polymerization of its corresponding monomer. The polymer is soluble in common solvents and thermally stable. The polymer shows good optical transparency with an absorption maximum at 393 nm and a band edge at ∼530 nm. Its poled film exhibits a resonant d33 value of 17.9 pm/V and its optical nonlinearity is resistant to thermal decay at up to 147 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5672–5681, 2006
Flame retardant epoxy resins based on diglycidyloxymethylphenylsilane
Authors: Mercado L. A. , Reina J. A. , Galià M. 
Published: August 2006

AbstractSilicon‐containing epoxy resins were prepared from diglycidyloxymethylphenyl silane (DGMPS) and diglycidylether of bisphenol A (DGEBA) by crosslinking with 4,4′‐diaminodiphenylmethane (DDM). Several DGMPS/DGEBA molar ratios were used to obtain materials with different silicon contents. Their thermal, dynamomechanical, and flame‐retardant properties were evaluated and related to the silicon content. The weight loss rate of the silicon‐containing resins is lower than that of the silicon free resin. Char yields under nitrogen and air atmospheres increase with the silicon content. The LOI (limited oxygen index) values increased from 24 for a standard commercial resin to 36 for silicon‐containing resins, demonstrating improved flame retardancy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5580–5587, 2006
Comparison of Atmospheric‐Pressure Plasma versus Low‐Pressure RF Plasma for Surface Functionalization of PTFE for Biomedical Applications
Authors: Sarra‐Bournet Christian , Turgeon Stephane , Mantovani Diego , Laroche Gaetan 
Published: August 2006

AbstractSummary: PTFE surface modifications have been realized using low‐pressure RFGD, DBD and APGD in different atmospheres. Compared to the RFGD NH3 plasma, the DBDs operating in H2/N2 lead to similar surface concentrations of amino groups and similar surface damage, but with a much higher specificity. Both APGDs in H2/N2 and NH3/N2 lead to lower concentrations of amino groups, but with similar specificity, and with lower surface damage than the RFGD treatment. A method is proposed to evaluate the efficiency of the different discharges for amine surface functionalization of PTFE, and it is concluded that the NH3/N2 APGD discharge is the one that give the best results for an effective surface treatment.Experimental setups for the DBD and the APGD plasma systems.magnified imageExperimental setups for the DBD and the APGD plasma systems.
Optimal design of clinical trials comparing several treatments with a control
Authors: Marschner Ian C. 
Published: August 2006

AbstractClinical trials are often designed to compare several treatments with a common control arm in pairwise fashion. In this paper we study optimal designs for such studies, based on minimizing the total number of patients required to achieve a given level of power. A common approach when designing studies to compare several treatments with a control is to achieve the desired power for each individual pairwise treatment comparison. However, it is often more appropriate to characterize power in terms of the family of null hypotheses being tested, and to control the probability of rejecting all, or alternatively any, of these individual hypotheses. While all approaches lead to unbalanced designs with more patients allocated to the control arm, it is found that the optimal design and required number of patients can vary substantially depending on the chosen characterization of power. The methods make allowance for both continuous and binary outcomes and are illustrated with reference to two clinical trials, one involving multiple doses compared to placebo and the other involving combination therapy compared to mono‐therapies. In one example a 55% reduction in sample size is achieved through an optimal design combined with the appropriate characterization of power. Copyright © 2006 John Wiley & Sons, Ltd.
Sample size calculation for the Power Model for dose proportionality studies
Authors: Sethuraman Venkat S. , Leonov Sergei , Squassante Lisa , Mitchell Toni R. , Hale Michael D. 
Published: August 2006

AbstractThere are several approaches to assess or demonstrate pharmacokinetic dose proportionality. One statistical method is the traditional ANOVA model, where dose proportionality is evaluated using the bioequivalence limits. A more informative method is the mixed effects Power Model, where dose proportionality is assessed using a decision rule for the estimated slope. Here we propose analytical derivations of sample sizes for various designs (including crossover, incomplete block and parallel group designs) to be analysed according to the Power Model. Copyright © 2006 John Wiley & Sons, Ltd.
In vitroanthelmintic activity ofMelia azedarachnaturalized in Argentina
Authors: Szewczuk Víctor D. , Mongelli Elena R. , Pomilio Alicia B. 
Published: August 2006

AbstractThe anthelmintic activity of the drupe extracts ofMelia azedarachL. (Meliaceae) growing in Argentina was tested against tapeworms, hookworms, nodular worms and earthworms, and was shown to be better than the standards piperazine phosphate and hexylresorcinol against tapeworms and hookworms, respectively. Copyright © 2006 John Wiley & Sons, Ltd.
Study on the Structure‐Activity Relationship of New Anti‐HIV Nucleoside Derivatives Based on the Support Vector Machine Method
Authors: Wang Jie , Liu Huanxiang , Qin Shen , Yao Xiaojun , Liu Mancang , Hu Zhide , Fan Botao 
Published: August 2006

AbstractSupport Vector Machine (SVM) was used for the classification of the activity of the new anti‐HIV nucleosides derivatives for a large and diverse data set using the twelve descriptors that were calculated from the molecular structure alone. The molecular descriptors were selected by the stepwise Linear Discriminant Analysis (LDA) method implemented in SPSS. The correlation between all the descriptors was lower than 0.85. At the same time, in order to build a nonlinear model to classify the new anti‐HIV drugs according to their activities, the data set was divided into two subgroups: the training set and the testing set. The nonlinear model gives satisfactory results, which can classify correctly 91.5% of the compounds in the training set and 91.4% of the compounds in the testing set. In addition, this paper provides a new and effective method for classifying the new anti‐HIV nucleoside derivatives from their structures according to their activities and gives some insight into structural features related to the activity of the drugs.
Quantitative Structure–Activity Relationships for Enzymatic Activity of Chloroperoxidase on Metabolizing Organophosphorus Pesticides
Authors: Lu Gui‐Ning , Dang Zhi , Tao Xue‐Qin , Chen Xiao‐Peng , Yi Xiao‐Yun , Yang Chen 
Published: August 2006

AbstractQuantitative Structure–Activity Relationship (QSAR) is a powerful approach for predicting activities of organic pollutants with their structure descriptors. This study reports QSAR models for predicting enzymatic activity of chloroperoxidase on metabolizing selected Organophosphorus Pesticides (OPPs). We used ten quantum chemical descriptors computed with ab initio method at HF/6‐31G(d) level and Partial Least Squares (PLS) analysis with optimizing procedure for generating QSAR models. The correlation coefficient of the optimal model was 0.918, and the fitting results showed that it had high fitting precision and good predicting ability. The PLS assistant analysis indicated that the atomic charges of sulfur and phosphorus atoms in the SP bond of an OPP molecule were important in governing the enzymatic activity and the molecular dipole moment also had some effect on the enzymatic activity. It was found that OPPs with high absolute values of atomic charges on the sulfur and phosphorus atoms tended to be metabolized faster, whereas OPPs with stronger polarity tended to be metabolized slower by chloroperoxidase. The optimal model was used to predict the enzymatic activity of two OPPs and the results appeared to be reasonable.
Development and validation of a liquid chromatography/tandem mass spectrometry method for the determination of the novel anticancer agent 17‐DMAG in human plasma
Authors: Moreno‐Farre Javier , Asad Yasmin , Pacey Simon , Workman Paul , Raynaud Florence I. 
Published: August 2006

AbstractAn accurate, sensitive, robust and selective liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the determination of 17‐(dimethylaminoethylamino)‐17‐demethoxygeldanamycin hydrochloride (17‐DMAG) in human plasma has been developed and validated. Plasma samples were prepared by liquid/liquid extraction with ethyl acetate. The chromatographic separation was achieved within 9 min on a Synergy Polar column with a linear gradient and a mobile phase consisting of methanol and 0.1% formic acid in water. Detection of 17‐DMAG and the internal standard (IS), olomoucine, was achieved by MS/MS with electrospray ionisation in positive ion mode. The calibration curve, ranging from 1.89 to 1890 nM, was linear r > 0.994 using a 1/y2 weighted linear regression. The assay showed no significant interferences from endogenous compounds. The lower limit of quantitation (LLOQ) was 1.89 nM, using 250 µL of plasma, with inter‐assay precision (%RSD) and accuracy (%RE) values of 11.6% and −5.8%, respectively. Intra‐assay precision ranged from 7.8–13.6%. The method described here is being used to evaluate the pharmacokinetic profiles of 17‐DMAG given as a once weekly infusion in patients with advanced solid tumours. Copyright © 2006 John Wiley & Sons, Ltd.
Conic S‐procedure and constrained dissipativity for linear systems
Authors: L. Fradkov A. 
Published: August 2006

AbstractA new proof and extension of the recent result of Iwasaki et al. (Systems Control Lett. 2005; 54(7):681–691) concerning equivalence of frequency domain inequality on finite frequency range and constrained dissipativity property for linear systems is given. The results of this paper employ an extended version of S‐procedure based on duality in the space of positive definite matrices and introduction of matrix Lagrange multipliers, proposed by Yakubovich in 1992. Copyright © 2006 John Wiley & Sons, Ltd.
Optimal designs for radiation retention with Poisson correlated response
Authors: López‐Fidalgo J. , Villarroel J. 
Published: August 2006

AbstractIn this paper we describe a non‐linear model with correlated observations which accounts for the elimination rate of radiation in the lung of individuals who have been exposed to an accidental intake at some time. The response is then modelled as a conditional Poisson distribution. When the leak is moderate or the size of the particles is large a theoretical justification of this assumption is given and D‐optimal designs are computed. Copyright © 2006 John Wiley & Sons, Ltd.