bluuebunny/crossref_metadata_2025_split huggingface dataset:
Proteomic changes in the pressure overloaded right ventricle after 6 weeks in young rats: Correlations with the degree of hypertrophy
Authors: Faber Matthijs J. , Dalinghaus Michiel , Lankhuizen Inge M. , Bezstarosti Karel , Dekkers Dick H. W. , Duncker Dirk J. , Helbing Willem A. , Lamers Jos M. J. 
Published: May 2005

AbstractRight ventricular (RV) hypertrophy is an important problem in congenital heart disease. We determined the alterations in phenotype that occur in the initial phase of RV hypertrophy and their possible correlations with the degree of hypertrophy. Therefore, we performed a differential proteomic profiling study on RV hypertrophy using an animal model of pulmonary artery banding (PAB) in parallel with hemodynamic characterization. The RV homogenates were subfractionated in myofilament and cytoplasmic proteins, which subsequently were separated by two‐dimensional gel electrophoresis (2‐DE), excised, and analyzed by mass spectrometry (MS). The cytoplasmic fraction showed expression changes in metabolic proteins, indicative of a shift from fatty acid to glucose as a substrate for energy supply. Up‐regulation of three HSP‐27s (1.9‐, 1.7‐, and 3.5‐fold) indicated an altered stress response in RV hypertrophy. Detailed analysis by immunoblotting and MS showed that two of these HSP‐27s were at least phosphorylated on Ser15. The myofilament fraction showed up‐regulation of desmin and α‐B‐crystallin (1.4‐and 1.3‐fold, respectively). This alteration in desmin was confirmed by 1‐DE immunoblots. Certain differentially expressed proteins, such as HSP‐27, showed a significant correlation with the RV weight to the body weight ratio in the PAB rats, suggesting an association with the degree of hypertrophy.
Effect of solvent on cis‐to‐trans isomerization of 4‐hydroxyazobenzene aggregated through intermolecular hydrogen bonds
Authors: Kojima Masanobu , Nebashi Satomi , Ogawa Keiichiro , Kurita Noriyuki 
Published: May 2005

AbstractThe half‐life (τ1/2) for thermal isomerization of cis‐4‐hydroxyazobenzene (c‐HOAB) to its trans isomer is highly dependent on the solvent used. For non‐aromatic solvents, the cis isomer is extremely unstable at 293 K (τ1/2 < 1 min in methanol and acetonitrile and 6 min in cyclohexane), whereas the cis isomer is surprisingly stable in benzene (τ1/2 = 125 min). However, addition of hydrogen chloride and triethylamine in benzene causes a remarkable decrease in τ1/2. On the basis of ab initio molecular orbital calculations of the binding energies and the optimum structures of c‐HOAB–solvent complexes, a mechanism for the thermal cis‐to‐trans isomerization reaction involving hydrogen‐bonded dimers and complexes is suggested. Copyright © 2005 John Wiley & Sons, Ltd.
Vinyl or isopropenyl substituents as experimental and theoretical probes for diamagnetic anisotropies of aromatic hydrocarbons
Authors: Haefelinger Guenter , Knapp Wolfgang , Zuschneid Thomas , Dietrich Frank Peter 
Published: May 2005

AbstractVinyl or isopropenyl substituents can be used to indicate anisotropy effects in the surroundings of benzenoid hydrocarbons by experiments together with APUDI model and ab initio GIAO MO calculations from the difference in geminal proton splittings of the olefinic substituents. Geometry optimizations as a function of the torsional angle between substituents and aromatic planes were performed in two polarized basis sets for the HF, B3LYP and MP2 methods. Calculated splittings range between −0.70 and 0.48 ppm. Comparison with experimental 1H NMR shifts does not lead precisely to the determination of the experimentally apparent effective torsional angle. Copyright © 2005 John Wiley & Sons, Ltd.
Metabolic mechanisms of insecticide resistance in the western flower thrips, Frankliniella occidentalis (Pergande)
Authors: Espinosa Pedro J , Contreras Josefina , Quinto Vicente , Grávalos Carolina , Fernández Esther , Bielza Pablo 
Published: May 2005

AbstractThe interactions between six insecticides (methiocarb, formetanate, acrinathrin, deltamethrin, methamidophos and endosulfan) and three potential synergists (piperonyl butoxide (PBO), S,S,S‐tributyl phosphorotrithioate (DEF) and diethyl maleate (DEM)) were studied by topical exposure in strains selected for resistance to each insecticide, and in a susceptible strain of Frankliniella occidentalis (Pergande). In the susceptible strain PBO produced appreciable synergism only of formetanate, methiocarb and methamidophos. Except for endosulfan, PBO synergized all the insecticides to varying degrees in the resistant strains. A very high level of synergism by PBO was found with acrinathrin, which reduced the resistance level from 3344‐ to 36‐fold. PBO slightly synergized the carbamates formetanate (4.6‐fold) and methiocarb (3.3‐fold). PBO also produced a high synergism of deltamethrin (12.5‐fold) and methamidophos (14.3‐fold) and completely restored susceptibility to both insecticides. DEF did not produce synergism with any insecticide in the resistant strains and DEM was slightly synergistic to endosulfan (3‐fold). These studies indicate that an enhanced detoxification, mediated by cytochrome P‐450 monooxygenases, is the major mechanism imparting resistance to different insecticides in F occidentalis. Implications of different mechanisms in insecticide resistance in F occidentalis are discussed. Copyright © 2005 Society of Chemical Industry
The intrinsic toxicity of several neonicotinoids to Lygus lineolaris and Hyaliodes vitripennis, a phytophagous and a predacious mirid
Authors: Bostanian Noubar J , Hardman John M , Ventard Estelle , Racette Gaétan 
Published: May 2005

AbstractThe tarnished plant bug Lygus lineolaris (Palisot de Beauvois) is a key pest of apples in eastern Canada and, currently, chemical control is the only way to manage this pest. Hyaliodes vitripennis (Say) is a univoltine indigenous predacious mirid and an integral part of biological control programs for apples in certain regions of Quebec. In worst‐case laboratory conditions, thiamethoxam, thiacloprid and acetamiprid were exceptionally toxic to this predacious mirid. The adults were more susceptible than the nymphs. However, the residual toxicity of these neonicotinoids to L lineolaris in orchards was very short‐lived. Because of the short residual toxicity, neonicotinoids should be applied when L lineolaris is at maximum abundance and well before eggs of H vitripennis hatch in late June. Copyright © 2005 Society of Chemical Industry
Singlet oxygen formation by porous Si in solution
Authors: Fujii Minoru , Usui Motofumi , Hayashi Shinji , Gross Egon , Kovalev Dmitri , Künzner Nicolei , Diener Joachim , Timoshenko Victor Yu. 
Published: May 2005

AbstractSinglet oxygen formation by porous Si in solution has been demonstrated. It has been shown that the absorption band of 1,3‐diphenylisobenzofuran (DPBF) in benzene becomes smaller, i.e., DPBF is degraded, by irradiating green or red light if the powder of fresh porous Si is dispersed in the solution. The effect was drastically suppressed by the formation of a monolayer of backbonded oxide at the surface of nanocrystals. The degradation was accelerated when the solution was bubbled with oxygen gas. These results indicate that electronic excitation of Si nanocrystals is transferred to molecular oxygen dissolved in solution, resulting in the formation of singlet oxygen. Generated singlet oxygen reacts with DPBF, forming endoperoxides, which in turn decompose to yield irreversible products. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhanced control of porous silicon morphology from macropore to mesopore formation
Authors: Ouyang Huimin , Christophersen Marc , Fauchet Philippe M. 
Published: May 2005

AbstractPorous silicon (PSi) is a versatile material that possesses a wide range of morphologies. There are two main types of microstructures that are widely used and well studied: branchy mesoporous silicon with pore sizes from 10 nm to 50 nm and classical macroporous silicon with pore sizes from 500 nm to 20 µm. Much less work has been done on structures with intermediate pore sizes from 100 nm to 300 nm. Applications such as immunoassays biosensing can greatly benefit from the intermediate morphology due to the larger pore openings compared to mesopores, and increased internal surface compared to classical macropores. In this work we demonstrate well‐defined macropore of 150 nm diameter in average and precise control of the porous silicon morphology transition from smooth macropores to branchy mesopores on one substrate with one electrolyte. A multilayer structure (microcavity) consisting of both mesopores and macropores is presented. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stain etching of silicon pillars and macropores
Authors: Mills David , Nahidi Mona , Kolasinski Kurt W. 
Published: May 2005

AbstractWe used a XeCl excimer laser (308 nm, ∼3 J cm–2) and chemically enhanced laser ablation in the presence of SF6 to create arrays of silicon pillars. Etching of these pillars with KOH leads to arrays of macropores whose morphology depends on surface crystallography. Several new stain etchants – containing some combination of HF, NH4HF2, HCl, HNO3, Fe(III), Mn(VII) and water – have been used to cover these structures with a layer of microporous silicon. Both pillars and macropores are black, i.e., exhibit low reflectivity across the visible spectrum. When porosified, pillars exhibit visible photoluminescence whose angular distribution differs from that of planar porous silicon with significantly more intensity at high angles. The peak photoluminescence wavelength depends on the stain etchant composition and exposure to air. The use of metal ions in place of HNO3 in the stain etchant ameliorates the production of gas bubbles and leads to more uniform films. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A three‐dimensional waveguide substrate for DNA‐microarrays based on macroporous silicon
Authors: Dertinger Stephan K. , Klühr Marco , Sauermann Alexander , Thein Kerstin 
Published: May 2005

AbstractIn this paper we present a three‐dimensional waveguide structure with unique optical and fluidic properties and demonstrate its application as a substrate for DNA microarrays. The structure is fabricated by thermal oxidation of a macroporous silicon membrane with a periodic pattern of discrete microchannels running perpendicular through the substrate. Partial oxidation generates compartments with channel walls that are completely converted into SiO2 but leaves a rectangular grid of silicon walls separating the SiO2 compartments. We demonstrate that the SiO2 walls act as optical waveguides and the opaque silicon walls divide the substrate into optically isolated compartments. In DNA microarray experiments, we show that the silicon walls of the compartments prevent cross talk between adjacent DNA spots. The structure is compatible with all conventional read‐out techniques such as fluorescence, chemiluminescence, and precipitation staining. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Possible model of protein nucleation and crystallization on porous silicon
Authors: Stolyarova S. , Baskin E. , Chayen N. E. , Nemirovsky Y. 
Published: May 2005

AbstractThe problem of macromolecular nucleation and crystallization on porous silicon surface is investigated theoretically. The fractality of the porous silicon layer is exploited. It is shown that the effective surface density of adsorbed particles on a fractal self‐similar surface significantly exceeds that on a flat surface. The resulting local supersaturation explains enhanced nucleation phenomena associated with porous silicon. In addition, the self‐affine fractal surface exhibits quasi‐periodicity that can facilitate long‐range ordering of the nucleated molecules, i.e. the crystallization process. Moreover, small elastic constants of porous silicon are favorable for the surface periodicity tuning to different lattice parameters of growing crystals. The anomalous large scaling range (from silicon interatomic distance up to 100 nm) is favorable for the crystallization of wide range of big macromolecules such as proteins. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of porous silicon formation on stiction in surface micromachined MEMS structures
Authors: Bhattacharya Enakshi , Rani Helen Anitha , Venu Babu U. , Rao P. R. S. , Bhat K. N. , Martin J. 
Published: May 2005

AbstractStiction, or adhesion of components to one another, is a major failure mechanism in surface micromachined MEMS. In this paper we discuss roughening of the surface of polysilicon, which forms the structural layer in surface micromachining, by the formation of porous silicon and its effect on stiction. The adhesivity of the surface is investigated by measurements of contact angle and the roughness is measured by a surface profiler. Measurements to estimate stiction on surface micromachined cantilevers and accelerometers are reported. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structural and light‐emission modification in chemically‐etched porous silicon
Authors: Navarro‐Urrios D. , Pérez‐Padrón C. , Lorenzo E. , Capuj N. E. , Gaburro Z. , Oton C. J. , Pavesi L. 
Published: May 2005

AbstractAfter electrochemical etching, we have made a study of the effects generated on p+‐type porous silicon layers when they are left in presence of the electrolyte for different post‐etching times. Using an interferometric technique, we have monitored the change of its porosity during the post‐etch process due to a chemical dissolution mechanism. These data are complemented with a study of photoluminescence and transmission electron microscopy measurements for different post‐etching times. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Si/SiO2 nanocomposite by CVD infiltration of porous SiO2
Authors: Amato G. , Borini S. , Rossi A. M. , Boarino L. , Rocchia M. 
Published: May 2005

AbstractThe aim of the present paper is to report first results on an innovative method for producing Si/SiO2 nanocomposites. Starting from a porous oxide structure, we infiltrated Si by Chemical Vapour Deposition of SiH4, under controlled conditions. In this way, we succeeded in infiltrating Si into the SiO2 template. Porous oxide is obtained by dry oxidation of mesoporous Si. By means of the electrochemical process used for producing porous Si, an interconnected pore structure is obtained. This allows for Si infiltration, giving rise, in principle, to an interconnected network of Si crystallites, in which electrical carriers are easily driven. Efficient charge injection in Si nanocrystals is of crucial importance for several applications, from electroluminescence to memory devices. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of the experimental procedure in the specific surface measurement by chemical dissolution of n+ nanoporous silicon
Authors: Descamps Y. , Dufour‐Gergam E. , Halimaoui A. 
Published: May 2005

AbstractIn this paper, we used the chemical dissolution of porous silicon (PS) to determine the specific surface area of PS obtained from n+ substrate. Two initial porosity values (62 and 39% with 1 µm and 0.5 µm thickness respectively) and two dissolution etchants were used. It is shown that the dissolution experimental procedure influences the extracted specific surface value. Under good dissolution conditions, we calculed 90 m2/cm3 and 130 m2/cm3 surface area value respectively. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Integrating packaging suppliers into the supply/demand chain
Authors: Dominic Chris 
Published: May 2005

AbstractThis paper presents the results from qualitative studies done on leading‐edge companies in supply/demand chain management in Sweden. The aim of the study was to create a knowledge base, identify the network integrators and, with reference to previous studies conducted in the packaging industry, analyse the development for packaging suppliers. Copyright © 2005 John Wiley & Sons, Ltd.
Assay of rotenone in river water by high‐throughput tandem mass spectrometry and multiple‐reaction monitoring methodology
Authors: Di Donna Leonardo , Mazzotti Fabio , Sindona Giovanni , Tagarelli Antonio 
Published: May 2005

AbstractThe high‐throughput analytical approach proposed for the assay of rotenone in lake and river waters presented here is based on atmospheric pressure chemical ionization (APCI) multiple‐reaction monitoring (MRM) methodology whereby the analyte and internal standard solutions are directly analyzed, without any previous chromatographic separation. The very good accuracy is obtained by the critical choice of a reference compound that shows gas‐phase chemistry similar to that of the analyte, by producing the same product ions selected for the MRM‐based assay. Copyright © 2005 John Wiley & Sons, Ltd.
Ion‐pairing reversed‐phase liquid chromatography/electrospray ionization mass spectrometric analysis of 76 underivatized amino acids of biological interest: a new tool for the diagnosis of inherited disorders of amino acid metabolism
Authors: Piraud Monique , Vianey‐Saban Christine , Petritis Konstantinos , Elfakir Claire , Steghens Jean‐Paul , Bouchu Denis 
Published: May 2005

AbstractSeventy‐six molecules of biological interest for the diagnosis of inherited disorders of amino acids (AA) metabolism have previously been demonstrated to be detectable in electrospray ionization tandem mass spectrometry (ESI‐MS/MS) positive mode without derivatization. Reversed‐phase liquid chromatography (RPLC) separation on different C18 columns using various perfluorinated carboxylic acids as ion‐pairing agents has been found suitable for coupling with MS/MS, and for the separation of AA. A new procedure was optimized in order to replace the usual ion‐exchange chromatographic, post‐column ninhydrin derivatization, time‐consuming routine method. This procedure allowed an adequate separation of all the molecules from other known interfering compounds, and a throughput of two samples per hour. Quantification limits for each molecule were found to be compatible with their measurement in plasma and urine. We validated the qualitative part of the method by analyzing plasma and urine samples from patients affected with several inherited disorders of AA metabolism. We validated the quantification of 16 AA using their stable isotopes as internal standard. The calibration curves were linear over the range 0–3 mM. The quantitative results obtained with the new method on 105 plasma and 99 urine samples were in good agreement with those obtained by the established routine method. Spiking experiments and precision results were also satisfactory. Copyright © 2005 John Wiley & Sons, Ltd.
Single run measurements of drug‐protein binding by high‐performance frontal analysis capillary electrophoresis and mass spectrometry
Authors: Wan Hong , Östlund Åsa , Jönsson Stefan , Lindberg Walter 
Published: May 2005

AbstractA novel drug‐protein binding measurement method based on high‐performance frontal analysis and capillary electrophoresis (HPFA/CE) is presented. A single run measurement approach is proposed to circumvent utilization of a calibration curve that is often performed with HPFA. A sensitive mass spectrometer is applied as a detector enabling the measurement of in vitro protein binding at lower drug concentrations. Unbound free fraction and binding constants can be determined by a single run measurement by consecutive injections of an internal drug standard, a buffer plug and a drug‐protein mixture. Effects of injection volumes on peak height and plateau profile were investigated in two different separation systems, non‐volatile buffer and volatile buffer, with UV and mass spectrometry detection, respectively. A simplified one‐to‐one binding model is employed to evaluate the proposed method by using both single and multiple drug concentrations to measure the unbound free fraction and calculate the binding constants of some selected compounds. The method is suitable for rapid and direct screening of the binding of a drug to a specific protein or drug‐plasma protein binding. Copyright © 2005 John Wiley & Sons, Ltd.
Quantitative analysis of 23‐hydroxybetulinic acid in mouse plasma using electrospray liquid chromatography/mass spectrometry
Authors: Yang Min , Wang Guang Ji , Wang Su Jun , Li Xiao Tian , Xu Yu Ping , Wang Song Pei , Xiang Jing De , Pan Shang Ren , Cao Guo Xian , Ye Wen Cai 
Published: May 2005

Abstract23‐Hydroxybetulinic acid is a newly isolated derivative of betulinic acid. The agent exhibits potential anti‐tumor activity and functions in this regard via apoptosis. In support of pharmacokinetic and toxicological evaluations, a new assay based on liquid chromatography/mass spectrometry (LC/MS) was developed for the quantitative analysis of 23‐hydroxybetulinic acid. Sample preparation consisted of extraction of the plasma by the addition of methylene chloride followed by centrifugation. Aliquots of the supernatant were analyzed using an isocratic reversed‐phase high‐performance liquid chromatography (HPLC) system coupled to a negative ion electrospray mass spectrometer. Molecules of 23‐hydroxybetulinic acid and the internal standard limonin were detected using selected ion monitoring at m/z 471 and 469, respectively. The limit of detection of 23‐hydroxybetulinic acid was 0.05 pg (0.11 fmol) injected on‐column (10 pg/mL, 5 μL injection volume), and the limit of quantitation was 10 pg (21.19 fmol, 2 ng/mL, 5 μL injection volume). 23‐Hydroxybetulinic acid was stable in plasma samples at –20°C for at least 3 weeks. The intra‐day and inter‐day coefficients of variation of the assay were 3.0 and 4.8%, respectively. The utility of the assay was demonstrated by measuring 23‐hydroxybetulinicacid in mouse plasma following intragastric administration (IG) in vivo. Pharmacokinetic parameters were calculated using the 3P97 pharmacokinetic software package. A two‐compartment, first‐order model was selected for pharmacokinetic modeling. The result showed that after IG of 200 mg/kg 23‐hydroxybetulinic acid, the plasma concentrations reached peaks at 2 h with Cmax of 3.1 μg/mL. The 200 mg/kg 23‐hydroxybetulinic acid suspension IG doses were found to have long elimination half‐lives of 25.6 h and low bioavailability of 2.3%. No interference was noted due to endogenous substances. These analytical methods should be of value in future studies related to the development and characterization of 23‐hydroxybetulinic acid. Copyright © 2005 John Wiley & Sons, Ltd.