bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optical Properties of Zinc Oxide Nanoparticles and Nanorods Synthesized Using an Organometallic Method
Authors: Kahn Myrtil L. , Cardinal Thierry , Bousquet Bruno , Monge Miguel , Jubera Véronique , Chaudret Bruno 
Published: October 2006

AbstractThe emission properties of nanocrystalline ZnO particles prepared following an organometallic synthetic method are investigated. Spherical particles and nanorods are studied. The shape of the particles and the ligands used are shown to influence the luminescence properties in the visible domain. Two different emissions are observed at 440 nm (≈2.82 eV) and at 580 nm (≈2.14 eV) that are associated with the presence of surface defects on the particles. The first emission corresponds to the well‐known yellow emission located at 580 nm (≈2.14 eV) with a lifetime of 1850 ns for 4.0 nm size ZnO nanoparticles. The second emission at 440 nm (≈2.82 eV) is observed when amine functions are present. This strong blue emission is associated with an excitation energy less than that associated with the yellow emission displaying a lifetime of nine nanoseconds. A possible hole trapping effect by the amine groups on the surface of the ZnO particles is discussed as the origin of this emission. The modification of the intensities between the two visible emissions for different particle shapes is proposed to be related to a specific location of the amine ligands on the surface of the particles.
Designer T cells by T cell receptor replacement
Authors: Sommermeyer Daniel , Neudorfer Julia , Weinhold Monika , Leisegang Matthias , Engels Boris , Noessner Elfriede , Heemskerk Mirjam H. M. , Charo Jehad , Schendel Dolores J. , Blankenstein Thomas , Bernhard Helga , Uckert Wolfgang 
Published: October 2006

AbstractT cell receptor (TCR) gene transfer is a convenient method to produce antigen‐specific T cells for adoptive therapy. However, the expression of two TCR in T cells could impair their function or cause unwanted effects by mixed TCR heterodimers. With five different TCR and four different T cells, either mouse or human, we show that some TCR are strong – in terms of cell surface expression – and replace weak TCR on the cell surface, resulting in exchange of antigen specificity. Two strong TCR are co‐expressed. A mouse TCR replaces human TCR on human T cells. Even though it is still poorly understood why some TCRα/β combinations are preferentially expressed on T cells, our data suggest that, in the future, designer T cells with exclusive tumor reactivity can be generated by T cell engineering.
Coordination Chemistry of 3‐Mercapto‐2‐(mercaptomethyl)propanoic Acid (Dihydroasparagusic Acid) with Iron and Nickel
Authors: Volkers Phillip I. , Rauchfuss Thomas B. , Wilson Scott R. 
Published: October 2006

AbstractThe first transition‐metal complexes bearing the natural product dihydroasparagusic acid, (HSCH2)2CHCO2H, as a ligand are reported. Various coordination modes and nuclearities are demonstrated for the chelating ligand by a series of iron and nickel complexes. Fe2[(SCH2)2CHCO2H](CO)6 retains carbonyl substitution reactivity typical of Fe2(SR)2(CO)6 complexes, yet carboxy coordination to FeI was unobserved. Coupling of the carboxylic acid with amines yields the corresponding amides Fe2[(SCH2)2CHC(O)NHR](CO)6 (R = Et, gly–O–tBu). Fe2[(SCH2)2CHCO2H](CO)4(PMe3)2 catalyzes H2 production, but no better than unfunctionalized alkyl dithiolate analogs. Reactions of the ligand with NiCl2(dppe) afforded mono‐, di‐, and trinuclear complexes. Noteworthy is Ni3[(SCH2)2CHCO2]2(dppe)2, which features an octahedrally coordinated NiII center linked to a pair of square‐planar NiII centers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A DFT Study on the Electronic and Redox Properties of [PW11O39(ReN)]n–(n = 3, 4, 5) and [PW11O39(OsN)]2–
Authors: Yan Li‐Kai , Dou Zhuo , Guan Wei , Shi Shao‐Qing , Su Zhong‐Min 
Published: October 2006

AbstractDFT calculations were carried out to investigate the electronic and redox properties of nitrido‐functionalized polyoxometalate species, [PW11O39(ReN)]n– (n = 3, 4, 5) and [PW11O39(OsN)]2–. The rhenium‐ and osmium‐nitrido effectively modify the electronic properties. The LUMOs in fully oxidized [PW11O39(ReN)]3– and [PW11O39(OsN)]2– are mainly concentrated on the Re and Os centers. The high‐valent transition metals Re and Os modify the components and energies of the LUMO. The LUMO energies of [PW11O39(ReN)]3– and [PW11O39(OsN)]2– are lower than that of related Keggin [PW12O40]3–. In addition, Re centers will prefer to accept the electrons in the first and second reduced process of fully oxidized [PW11O39(ReN)]3–. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Diastereoselective Synthesis of Conformationally Restricted Dinucleotides Featuring Canonical and Noncanonical α/β Torsion Angle Combinations(α,β‐D‐CNA)
Authors: Dupouy Christelle , Le Clézio Ingrid , Lavedan Pierre , Gornitzka Heinz , Escudier Jean‐Marc , Vigroux Alain 
Published: October 2006

AbstractThe synthesis of the four possible diastereoisomers of α,β‐D‐CNA 5′‐XT (X = A, T, G and C) building units of nucleic acids, in which the α and β torsional angles are stereocontrolled by a dioxaphosphorinane ring structure (D‐CNA family) is described. The crystal structure analysis of the (RC5′,SP)‐configured α,β‐D‐CNA TT dimer demonstrates that the α and β torsional angles are restricted to the canonical {gauche(–),trans} conformation typically observed in DNA duplexes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Voltammetric Behavior of Antileukemia Drug Glivec. Part III: In Situ DNA Oxidative Damage by the Glivec Electrochemical Metabolite
Authors: Diculescu Victor Constantin , Vivan Marilene , Brett Ana Maria Oliveira 
Published: October 2006

AbstractGlivec is a relatively small molecule with activity against the protein tyrosine kinase, a protein expressed by all patients with chronic myelogenous leukemia (CML). Based on its activity on CML, glivec is undergoing extensive evaluation of its activity against other types of tumor. As a result, there is an ongoing need for clarification of glivec pharmacokinetics so that issues such as drug‐biomolecular complex interactions can be understood.
Electrochemical Detection of Short DNA Oligomer Hybridization Using the CombiMatrix ElectraSense Microarray Reader
Authors: Roth Kristian M. , Peyvan Kia , Schwarzkopf Kevin R. , Ghindilis Andrei 
Published: October 2006

AbstractA microarray reader named ElectraSense using an electrochemical detection technique has been developed for the CombiMatrix CustomArray 12 544 electrode semiconductor DNA microarray. The detection is based on electrochemical reduction of the enzymatic oxidization product of 3,3′,5,5′‐tetramethylbenzidene (TMB). TMB oxidation is catalyzed by a horseradish peroxidase (HRP) biomarker linked to a DNA target molecule through biotin‐avidin chemistry. Electrochemical signal collection is performed by a computer controlled combinatorial semiconductor addressing instrument. Electrode to electrode switching can be accomplished in hundreds of microseconds and a detection time for each electrode is less than 5 ms. The whole array detection requires less than 60 s. Numerous parameters of the measurement procedure have been optimized and assay performance has been studied and a method for array quality control has been developed. Application of electrochemical detection of Combimatrix microarrays has been demonstrated for DNA detection over 4 orders of magnitude of target concentrations and detection of avian influenza subtype H5N1.
Electrochemical and Sensorial Behavior of SOD Mutants Immobilized on Gold Electrodes in Aqueous/Organic Solvent Mixtures
Authors: Kapp A. , Beissenhirtz M. K. , Geyer F. , Scheller F. , Viezzoli M. S. , Lisdat F. 
Published: October 2006

AbstractA cysteine mutant of a monomeric human Cu, Zn‐SOD (Glycine 61, Serine 142) has been immobilized directly on gold electrodes using the thiol groups introduced. The electrochemical behavior of the surface confined protein was studied in mixtures of aqueous buffer and DMSO up to an organic solvent content of 60%. The formal potential was found to be rather independent of the DMSO content. However, half peak width increased and the redoxactive amount clearly decreased with raising DMSO content. In addition, the kinetics of the heterogeneous electron transfer became slower; but still a quasireversible electrochemical conversion of the mutant SOD was feasible. Thus, the electrodes were applied for sensorial superoxide detection. At a potential of +220 mV vs. Ag/AgCl advantage was taken of the partial oxidation reaction of the enzyme. A defined superoxide signal was obtained in solutions up to 40% DMSO. The sensitivity of the mutant electrodes decreased linearly with the organic solvent content in solution but was still higher compared to conventional cyt.c based sensors. At DMSO concentrations higher than 40% no sensor response was detected.
Miniature Biofuel Cells with Improved Stability Under Continuous Operation
Authors: Fischback Michael B. , Youn Jong Kyu , Zhao Xueyan , Wang Ping , Park Hyun Gyu , Chang Ho Nam , Kim Jungbae , Ha Su 
Published: October 2006

AbstractWe have developed miniature biofuel cells (BFCs) with dimensions as small as 12×12×9 mm by adopting the design of stackable proton exchange membrane (PEM) fuel cells. The enzymatic anodes were constructed by using stabilized glucose oxidase (GOx) in the form of crosslinked enzyme clusters (CECs) on the surface of carbon nanotubes (CNTs). The combination of stabilized GOx and unbuffered fuel solution resulted in stabilized performance of miniature BFCs under continuous operation for more than 16 hours. This unprecedentedly high operational stability of miniature BFCs opens up new possibilities for many BFC applications.
Dielectrophoretic investigation of plant virus particles: Cow Pea Mosaic Virus and Tobacco Mosaic Virus
Authors: Ermolina Irina , Milner Joel , Morgan Hywel 
Published: October 2006

AbstractThis paper reports experimental results on the dielectrophoretic (DEP) behaviour on two nonenveloped plant viruses of different geometrical shapes, namely Cow Pea Mosaic Virus (CPMV) and Tobacco Mosaic Virus (TMV). The DEP properties of carboxy‐modified latex beads of the same size are also reported. The DEP properties of single particles were obtained from measurement of the frequency at which the DEP force on a particle goes to zero (the crossover frequency). The DEP behaviour of particle ensembles was also measured using image processing. The dielectric properties of the particles were evaluated from the DEP data. The surface conductance was found to be 0.3 nS for CPMV, 0.38 nS for TMV, and 0.52 nS for 27 nm diameter carboxy–latex beads. Data analysis has shown that the optimal condition for separation of TMV and CPMV is a low‐conductivity suspending medium – below 1 mS/m.
Divide and conquer: Rat liver tissue proteomics based on the analysis of purified constituents
Authors: Teufelhofer Olga , Parzefall Wolfram , Elbling Leonilla , Kainzbauer Eveline , Grasl‐Kraupp Bettina , Zielinski Christoph , Schulte‐Hermann Rolf , Gerner Christopher 
Published: October 2006

AbstractComparative proteome data of normal and diseased tissue samples are difficult to interpret. Proteins detected in tissues are derived from different cell types and blood constituents. Pathologic or toxicant‐induced aberrations may affect the proteome profile of tissues in several ways since different cell types may respond in very different and highly specific manners. The aim of this study was to analyze the proteome profiles of purified rat liver primary cells and of blood plasma in comparison to liver whole tissue. Moreover, we investigated alterations of these profiles induced by the liver toxicant N‐nitrosomorpholine (NNM) used as a model compound. Whole liver samples, pure hepatocytes and Kupffer cells as well as blood plasma were obtained from saline‐ or NNM‐treated rats. Proteins were separated by 2‐D PAGE and their amounts were estimated by fluorography. Selected proteins were identified by MS analysis of tryptic digests. Among them we identified proteins exclusively expressed in the analysed constituents. Several of these proteins were assigned in the proteome profile of whole‐tissue homogenates. Furthermore, we identified several proteins that were modified, up‐regulated or down‐regulated due to NNM treatment in total liver homogenates. Some of these protein alterations were specifically detected in primary cells isolated from NNM‐treated rats. Thus, we demonstrated the successful assignment of NNM‐induced proteome alterations in rat liver to the cell type of origin. The currently applied approach may help to better understand pathologic processes at a whole‐tissue level.
Estimation of the composition of recombinant human erythropoietin mixtures using capillary electrophoresis and multivariate calibration methods
Authors: Benavente Fernando , Giménez Estela , Olivieri Alejandro C. , Barbosa José , Sanz‐Nebot Victoria 
Published: October 2006

AbstractA multivariate calibration method using partial least‐squares (PLS) is proposed in order to characterize binary mixtures of two types of recombinant human erythropoietin (epoetin alpha and beta), based on the analysis of the highly overlapped UV‐electrophoretic profiles obtained with the CE methodology recommended by the European Pharmacopoeia (EurPh). A two‐factor PLS‐1 model was developed and validated using mixtures of alpha and beta epoetins. Glycoforms were identified according to their effective electrophoretic mobility values and the normalized area values of each glycoform peak were used as multivariate data. Calibration and validation results were satisfactory. The PLS‐1 model was successfully used for determination of epoetin alpha and beta contents in the rHuEPO provided by the EurPh as a biological reference product.
A methodology for the graphical determination of operating conditions of chromatographic sequences incorporating the trade‐offs between purity and yield
Authors: Salisbury Rebecca S. , Bracewell Daniel G , Titchener‐Hooker Nigel J 
Published: October 2006

AbstractMultiple‐step chromatography sequences are necessary in biopharmaceutical downstream processing to achieve the desired levels of purity for products such as therapeutic proteins. Traditional methods of process design deal with each step individually, but this can result in a sequence that does not achieve best overall performance. This paper proposes a graphical methodology for the identification of operating conditions for a two‐step chromatography sequence. The method uses windows of operation to incorporate the trade‐offs between yield, purity and productivity. A tie‐line procedure is developed that separates the window of operation for the first chromatographic step into two zones. One zone contains those operating conditions that combine to produce a material which can be purified successfully by the second step to produce a product that meets the desired specifications. The second zone consists of operating conditions which will not yield a material that can be adequately purified by a second chromatographic stage to yield a product of the predetermined specifications. The methodology is valuable in that it helps in achieving the rapid design of a two‐step chromatography sequence, and aids in choosing the optimum operating conditions for the first step that are highly dependent upon the operation and specifications of the second chromatographic step. Simulations carried out using a software package based on the general rate model depict the construction and use of the method applied to a sequence of ion exchange and hydrophobic interaction chromatography separating a three‐component protein mixture. Copyright © 2006 Society of Chemical Industry
An OriP/EBNA‐1‐based baculovirus vector with prolonged and enhanced transgene expression
Authors: Shan Liang , Wang Leyao , Yin Juan , Zhong Peng , Zhong Jiang 
Published: October 2006

AbstractBackgroundThe baculovirus Autographa californica multiple nucleopolyhedrovirus (AcMNPV) has been explored as a gene delivery vehicle for a variety of mammalian cell lines. However, the transient expression nature due to its incapability to replicate in mammalian cells and insufficient transduction efficiency limit its application.MethodsRecombinant baculovirus vectors containing genetic elements from Epstein‐Barr virus (EBV), OriP and EBNA‐1, which are essential for the episomal maintenance of the EBV genome in latently infected cells, were constructed and tested for their ability to sustain and express transgene (enhanced green fluorescence protein (egfp)) in mammalian cells.ResultsThe recombinant baculovirus containing OriP and EBNA‐1 genes driven by the cytomegalovirus (CMV) promoter was capable of persisting in a significant proportion of infected mammalian cells, HEK293, Vero, Cos‐7, and Hone‐1, without any selective pressure. In HEK293, the expression of EGFP lasted for 60 days with markedly enhanced expression level. The persistence of baculovirus genome correlated with the expression of EBNA‐1.ConclusionsThe improved baculovirus vector could mediate prolonged and enhanced foreign gene expression in some mammalian cells. Furthermore, an adequate level of the EBNA‐1 protein was essential for the maintenance of the OriP‐containing baculovirus genome. The new vector has potential for use in gene therapy. Copyright © 2006 John Wiley & Sons, Ltd.
In vitro study comparing two collageneous membranes in view of their clinical application for rotator cuff tendon regeneration
Authors: Fini Milena , Torricelli Paola , Giavaresi Gianluca , Rotini Roberto , Castagna Alessandro , Giardino Roberto 
Published: October 2006

AbstractTenocytes were isolated from the rotator cuff tendons of healthy (HT) and glucocorticoid (GC)‐treated rats (GCT) and were cultured on polystyrene wells (TCP) as control, and on 2 de‐cellularized collagen matrices: porcine small intestinal submucosa (SIS), and human dermal matrix (Graftjacket®, GJ). At 3 and 7 days cell proliferation and synthesis were evaluated. Proliferation of HT tenocytes increased between experimental times for both tested membranes, but already at 3 days, HT tenocytes cultured on GJ showed the highest WST‐1 value. The collagen‐I (CICP) synthesis on GJ membrane did not change between experimental times and was significantly higher than TCP and SIS at 7 days. Proteoglycans (PG), and fibronectin (FBN) synthesis increased when HT were cultured on GJ, between experimental times, and both PG and FBN synthesis on GJ membrane were higher than TCP and SIS at 7 days. GC determined decreases in cell proliferation, CICP and PG syntheses at 3 days of culture on TCP when compared to HT tenocytes while a decrease in WST‐1 was maintained at 7 days. CICP, PG and FBN (only at 3 days) syntheses were significantly higher in GCT tenocytes cultured on GJ. The negative effects on GC on GCT tenocytes cultured on membrane were particularly evident on SIS for CICP (−18%) and FBN (−67%) synthesis. The obtained results support the conclusion that GJ is more suitable than SIS as a scaffold for in situ tissue engineering and for the in vitro bioengineering of tendons to heal massive tears of the rotator cuff tendon. © 2006 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:98–107, 2007
Hypocholesterolaemic and antioxidant effects of Glycyrrhiza glabra (Linn) in rats
Authors: Visavadiya Nishant P. , Narasimhacharya Amaravadi V. R. L. 
Published: October 2006

AbstractThe hypocholesterolaemic and antioxidant effects of Glycyrrhiza glabra (GG) root powder were examined in hypercholesterolaemic male albino rats. A 4‐week administration of GG root powder (5 and 10 gm% in diet) to hypercholesterolaemic rats resulted in significant reduction in plasma, hepatic total lipids, cholesterol, triglycerides and plasma low‐density lipoprotein and VLDL‐cholesterol accompanied by significant increases in HDL‐cholesterol levels. Furthermore, significant increases in fecal cholesterol, neutral sterols and bile acid excretion along with an increase in hepatic HMG‐CoA reductase activity and bile acid production were observed in these animals. The root powder administration to hypercholesterolaemic rats also decreased hepatic lipid peroxidation with a concomitant increase in superoxide dismutase (SOD) and catalase activities and total ascorbic acid content. Thus, the hypocholesterolaemic and antioxidant effects of GG root appeared to be mediated via (i) accelerated cholesterol, neutral sterol and bile acid elimination through fecal matter with an increased hepatic bile acid production and (ii) improving the activities of hepatic SOD, catalase and increasing the ascorbic acid content. The normo‐cholesterolaemic animals when fed with GG root powder at 10 gm% level, registered a significant decline in plasma lipid profiles and an increase in HDL‐cholesterol content. The antioxidant status of these animals also was improved upon treatment.
Analysis of the complex thermal behavior of poly(L‐lactic acid) film. II. Samples crystallized from the melt
Authors: Ling Xiaoyun , Spruiell Joseph E. 
Published: October 2006

AbstractThe complex thermal behavior of poly(l‐lactic acid) films crystallized from the melt, either isothermally or nonisothermally, was studied by differential scanning calorimetry (DSC), wide angle X‐ray diffraction, and small angle X‐ray scattering. The variation of the thermal behavior with crystallization temperature, time, and cooling rate was documented and analyzed. After nonisothermal crystallization at low cooling rates that develop high crystallinity, an obvious double melting peak appears at modest heating rates (e.g., 10 °C/min). At higher heating rates, these samples exhibit only single melting. However, an unusual form of double melting occurs under the majority of the conditions studied under either isothermal or nonisothermal conditions. In this case, double melting is marked by the appearance of a recrystallization exotherm just prior to the final melting that obscures the observation of the melting of the crystals formed during the initial crystallization process. The occurrence of double melting in melt‐crystallized samples was concluded to be the result of a melt‐recrystallization process occurring during the subsequent DSC heating scan; it is a function of crystalline perfection, not the initial crystallinity, nor whether or not the crystallization reached completion at the crystallization temperature. Many other very interesting observations are also discussed. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 3378–3391, 2006
Harmonised pesticide risk trend indicator for food (HAPERITIF): the methodological approach
Authors: Calliera Maura , Finizio Antonio , Azimonti Giovanna , Benfenati Emilio , Trevisan Marco 
Published: October 2006

AbstractTo provide a harmonised European approach for pesticide risk indicators, the Sixth EU Framework Programme recently financed the HAIR (HArmonised environmental Indicators for pesticide Risk) project. This paper illustrates the methodology underlying a new indicator—HAPERITIF (HArmonised PEsticide RIsk Trend Indicator for Food), developed in HAIR, for tracking acute and chronic pesticide risk trends for consumers. The acute indicator, HAPERITIFac, is based on the ratio between an estimated short‐term intake (ESTI), calculated as recommended by the World Health Organisation (WHO), and the acute reference dose (ARfD); the chronic indicator HAPERITIFchr is based on the ratio between an estimated daily intake (EDI) and the admissible daily intake (ADI). HAPERITIF can be applied at different levels of aggregation. Each level gives information for proper risk management of pesticides to reduce the risk associated with food consumption. An example of application using realistic scenarios of pesticide treatments on a potato crop in central‐northern Italy is reported to illustrate the different steps of HAPERITIF. Copyright © 2006 Society of Chemical Industry