bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of CNTO 530, an erythropoietin mimetic‐IgG4 fusion protein, on embryofetal development in rats and rabbits
Authors: Martin Pauline L. , Sachs Clifford , Hoberman Alan , Jiao Qun , Bugelski Peter J. 
Published: January 2010

AbstractBACKGROUND: CNTO 530is a biopharmaceutical consisting of a novel peptide that mimics the actions of erythropoietin, fused to the Fc fragment of human IgG4. Pharmacokinetic and pharmacodynamic studies showed that CNTO 530 produced sustained increases in red blood cell parameters in rats and rabbits and that the serum half life of CNTO 530 was 2 days in rabbits and 3 days in rats. METHODS: For the evaluation of embryofetal development, CNTO 530 was injected at loading doses of 0, 0.9/1, 6, or 60 mg/kg subcutaneously (SC) on gestation day (GD)7 followed by maintenance doses of 0, 0.3, 2, or 20 mg/kg SC every 3 days through GD16 in rats and every 2 days through GD19 in rabbits (GD0 was the day of mating). Rats were Caesarean sectioned on GD21, rabbits on GD29. RESULTS: Administration of CNTO 530 was associated with an increase in hematocrit at all dose levels and a decrease in maternal body weight gains. Fetuses exhibited reduced body weight and delayed ossification. Soft tissue changes were limited to cardiovascular alterations in the high‐dose rabbits only. Rat and rabbit fetuses were exposed to CNTO 530 in all dose groups. CONCLUSIONS: These studies show that the embryo/fetal development effects observed following CNTO 530 treatment during organogenesis are qualitatively similar to those seen with other erythropoietin agonists and are likely a secondary consequence of increased hematocrit in the dams. Unlike other erythropoietin receptor agonists, CNTO 530 was able to cross the placental barrier, which was considered likely the result of FcRn‐mediated transcytosis. Birth Defects Res (Part B) 89:87–96, 2010. © 2010 Wiley‐Liss, Inc.
Functional comparison of hemoglobin purified by different methods and their biophysical implications
Authors: Elmer Jacob , Buehler Paul W. , Jia Yiping , Wood Francine , Harris David R. , Alayash Abdu I. , Palmer Andre F. 
Published: January 2010

AbstractHemoglobin (Hb) that is purified from red blood cells (RBCs) is commonly subjected to harsh processing conditions, such as high temperatures and extensive column separation, which may damage the Hb by altering the heme prosthetic group and/or the Hb protein structure. In this study, bovine and human Hb purified by tangential flow filtration (TFF) was compared to commercial preparations of human Hb (Hemosol, Inc., Toronto, Canada) and bovine Hb (Biopure, Inc., Cambridge, MA). Purified Hbs were characterized by measuring their overall purity (SDS–PAGE, SEC, and ESI‐MS), susceptibility to oxidation (kox), responses to physiological conditions (pH, [Cl−], [IHP], and T), and ligand binding kinetics (O2, NO, and CO). All Hbs evaluated possessed comparable biophysical properties, however, a small amount of catalase was detected in the TFF‐purified Hbs that reduced the rate of autoxidation. Mass changes observed by mass spectrometry suggest that structural alterations may be introduced into Hbs that are purified by extensive chromatographic separations. These results demonstrate that TFF is a suitable process for the purification of Hb from RBCs with a quality equivalent to that of commercial Hb preparations that employ more extensive purification strategies. This work also shows that TFF can yield highly pure Hb which can be used for Hb‐based O2 carrier synthesis. Biotechnol. Bioeng. 2010; 106: 76–85. © 2010 Wiley Periodicals, Inc.
TCR‐β repertoire analysis of antigen‐specific single T cells using a high‐density microcavity array
Authors: Arakaki Atsushi , Ooya Kaori , Akiyama Yasuto , Hosokawa Masahito , Komiyama Masaru , Iizuka Akira , Yamaguchi Ken , Matsunaga Tadashi 
Published: January 2010

AbstractThe antigen specificity of cytotoxic T cells, provided by T‐cell receptors (TCRs), plays a central role in human autoimmune diseases, infection, and cancer. As the TCR repertoire is unique in individual cytotoxic T cells, a strategy to analyze its gene rearrangement at the single‐cell level is required. In this study, we applied a high‐density microcavity array enabling target cell screening of several thousands of single cells for identification of functional TCR‐β gene repertoires specific to melanoma (gp100) and cytomegalovirus (CMV) antigens. T cells expressing TCRs with the ability to recognize fluorescent‐labeled antigen peptide tetramers were isolated by using a micromanipulator under microscopy. Regularly arranged cells on the microcavity array eased detection and isolation of target single cells from a polyclonal T‐cell population. The isolated single cells were then directly utilized for RT‐PCR. By sequencing the amplified PCR products, antigen‐specific TCR‐β repertoires for gp100 and human cytomegalovirus antigens were successfully identified at the single‐cell level. This simple, accurate, and cost‐effective technique for single‐cell analysis has further potential as a valuable and widely applicable tool for studies on gene screening and expression analyses of various kinds of cells. Biotechnol. Bioeng. 2010;106: 311–318. © 2010 Wiley Periodicals, Inc.
Insulin-like growth factor 1-coated sutures improve anastomotic healing in an experimental model of colitis
Authors: Rijcken E , Fuchs T , Sachs L , Kersting C M , Bruewer M , Krieglstein C F 
Published: January 2010

Abstract

Background
Exogenously applied insulin-like growth factor (rhIGF-1) may improve normal intestinal healing. This study examined the effect of rhIGF-1-coated sutures on anastomotic healing in experimental colitis.

Methods
Acute colitis was induced in rats by dextran sodium sulphate (DSS). Inflammation was assessed by clinical Disease Activity Index (DAI), myeloperoxidase (MPO) measurement and histological examination. A distal colonic anastomosis was performed using sutures coated with rhIGF-1 dissolved in poly(d,l-lactide) (PDLLA) under general anaesthetic. Anastomotic healing was evaluated histologically, and by hydroxyproline measurement and bursting parameters after 1, 3 and 7 days, and compared with healthy, DSS and DSS + PDLLA controls.

Results
DAI, MPO and histological inflammation scores were significantly increased in all animals treated with DSS. Bursting occurred less often within the anastomotic line on day 3 in the IGF group than in DSS controls (three versus eight of ten). On day 7, the IGF group had significantly increased histological healing scores (mean(s.e.m.) 12·5(0·7) versus 9·2(0·8) (P &lt; 0·050)) and hydroxyproline content (4·6(0·3) versus 3·6(0·1) mg/g tissue; P &lt; 0·050) compared with DSS controls.

Conclusion
IGF-1-coated sutures improve important aspects of anastomotic healing in rats with experimental colitis.
New protocol to obtain spirolides from Alexandrium ostenfeldii cultures with high recovery and purity
Authors: Otero Paz , Alfonso Amparo , Alfonso Carmen , Vieytes Mercedes R. , Louzao M. Carmen , Botana Ana M. , Botana Luis M. 
Published: January 2010

AbstractThe aim of this work was to develop a method to purify large amounts of spirolide toxins from cultures of Alexandrium ostenfeldii. The dinoflagellates grew in batches under controlled conditions of salinity, light and temperature. Analysis of the cultures demonstrated the existence of neurotoxins associated with paralytic shellfish poisoning toxins and two spirolides, 13‐desmethyl spirolide C and 13,19‐didesmethyl spirolide C. The protocol designed presents several stages of extraction, separation between spirolides and paralytic shellfish poisoning toxins, and cleanup in solid‐phase extraction. Finally, the purification of spirolides was conducted by a preparative high‐performance liquid chromatography system coupled to a mass spectrometer detector. The purity and the amount of both toxins in each step was monitored by analytical liquid chromatographic–mass spectrometry. Large amounts of 13‐desMeC, 97% pure, and 13,19‐didesMeC, 99% pure, were obtained. A novel and efficient method to separate and purify spirolide toxins from large amounts of phytoplankton is provided. The protocol proposed shows, for the first time, a complete and detailed methodology to separate and purify spirolide toxins with high purity, recovery, repeatability and stability. Copyright © 2010 John Wiley & Sons, Ltd.
A Quadruplex‐Based, Label‐Free, and Real‐Time Fluorescence Assay for RNase H Activity and Inhibition
Authors: Hu Dan , Pu Fang , Huang Zhenzhen , Ren Jinsong , Qu Xiaogang 
Published: January 2010

AbstractWe demonstrate a unique quadruplex‐based fluorescence assay for sensitive, facile, real‐time, and label‐free detection of RNase H activity and inhibition by using a G‐quadruplex formation strategy. In our approach, a RNA–DNA substrate was prepared, with the DNA strand designed as a quadruplex‐forming oligomer. Upon cleavage of the RNA strand by RNase H, the released G‐rich DNA strand folds into a quadruplex in the presence of monovalent ions and interacts with a specific G‐quadruplex binder, N‐methyl mesoporphyrin IX (NMM); this gives a dramatic increase in fluorescence and serves as a reporter of the reaction. This novel assay is simple in design, fast in operation, and is more convenient and promising than other methods. It takes less than 30 min to finish and the detection limit is much better or at least comparable to previous reports. No sophisticated experimental techniques or chemical modification for either RNA or DNA are required. The assay can be accomplished by using a common spectrophotometer and obviates possible interference with the kinetic behavior of the catalysts. Our approach offers an ideal system for high‐throughput screening of enzyme inhibitors and demonstrates that the structure of the G‐quadruplex can be used as a functional tool in specific fields in the future.
Attachment of a Hydrogen‐Bonding Carboxylate Side Chain to an [FeFe]‐Hydrogenase Model Complex: Influence on the Catalytic Mechanism
Authors: Gao Weiming , Sun Junliang , Åkermark Torbjörn , Li Mingrun , Eriksson Lars , Sun Licheng , Åkermark Björn 
Published: January 2010

AbstractAzapropanedithiolate (adt)‐bridged model complexes of [FeFe]‐hydrogenase bearing a carboxylic acid functionality have been designed with the aim of decreasing the potential for reduction of protons to hydrogen. Protonation of the bisphosphine complexes 4–6 has been studied by in situ IR and NMR spectroscopy, which revealed that protonation with triflic acid most likely takes place first at the N‐bridge for complex 4 but at the FeFe bond for complexes 5 and 6. Using an excess of acid, the diprotonated species could also be observed, but none of the protonated species was sufficiently stable to be isolated in a pure state. Electrochemical studies have provided an insight into the catalytic mechanisms under strongly acidic conditions, and have also shown that complexes 3 and 6 are electro‐active in aqueous solution even in the absence of acid, presumably due to hydrogen bonding. Hydrogen evolution, driven by visible light, has been observed for three‐component systems consisting of [Ru(bpy)3]2+, complex 1, 2, or 3, and ascorbic acid in CH3CN/D2O solution by on‐line mass spectrometry.
Determination of the Absolute Configuration of Pentacoordinate Chiral Phosphorus Compounds in Solution by Using Vibrational Circular Dichroism Spectroscopy and Density Functional Theory
Authors: Yang Guochun , Xu Yunjie , Hou Jianbo , Zhang Hui , Zhao Yufen 
Published: January 2010

AbstractVibrational circular dichroism (VCD) spectroscopic measurements and density functional theory (DFT) calculations have been used to obtain the absolute structural information about four sets of diastereomers of pentacoordinate spirophosphoranes derived separately from l‐ (or d‐) valine and l‐ (or d‐) leucine for the first time. Each compound contains three stereogenic centers: one at the phosphorus center and two at the amino acid ligands. Extensive conformational searches for the compounds have been carried out and their vibrational absorption (VA) and VCD spectra have been simulated at the B3LYP/6‐311++G** level. Although both VA and VCD spectra are highly sensitive to the structural variation of the apical axis, that is, the OPO or NPO arrangement, the rotamers generated by the aliphatic amino side chains show little effect on both. The dominant experimental VCD features in the 1100–1500 cm−1 region were found to be controlled by the chirality at the phosphorus center, whereas those at the CO stretching region are determined by the chirality of the amino acid ligands. The good agreement between the experimental VA and VCD spectra in CDCl3 solution and the simulated ones allows us to assign the absolute configurations of these pentacoordinate phosphorus compounds with high confidence. This study shows that the VCD spectroscopy complemented with DFT calculations is a powerful and reliable method for determining the absolute configurations and dominating conformers of synthetic phosphorus coordination complexes in solution.
Aggregation and Contingent Metal/Surface Reactivity of 1,3,8,10‐Tetraazaperopyrene (TAPP) on Cu(111)
Authors: Matena Manfred , Stöhr Meike , Riehm Till , Björk Jonas , Martens Susanne , Dyer Matthew S. , Persson Mats , Lobo‐Checa Jorge , Müller Kathrin , Enache Mihaela , Wadepohl Hubert , Zegenhagen Jörg , Jung Thomas A. , Gade Lutz H. 
Published: January 2010

AbstractThe structural chemistry and reactivity of 1,3,8,10‐tetraazaperopyrene (TAPP) on Cu(111) under ultra‐high‐vacuum (UHV) conditions has been studied by a combination of experimental techniques (scanning tunneling microscopy (STM) and X‐ray photoelectron spectroscopy, XPS) and DFT calculations. Depending on the deposition conditions, TAPP forms three main assemblies, which result from initial submonolayer coverages based on different intermolecular interactions: a close‐packed assembly similar to a projection of the bulk structure of TAPP, in which the molecules interact mainly through van der Waals (vDW) forces and weak hydrogen bonds; a porous copper surface coordination network; and covalently linked molecular chains. The Cu substrate is of crucial importance in determining the structures of the aggregates and available reaction channels on the surface, both in the formation of the porous network for which it provides the Cu atoms for surface metal coordination and in the covalent coupling of the TAPP molecules at elevated temperature. Apart from their role in the kinetics of surface transformations, the available metal adatoms may also profoundly influence the thermodynamics of transformations by coordination to the reaction product, as shown in this work for the case of the Cu‐decorated covalent poly(TAPPCu) chains.
Vectorial Electron Transfer in Donor–Photosensitizer–Acceptor Triads Based on Novel Bis‐tridentate Ruthenium Polypyridyl Complexes
Authors: Kumar Rohan J. , Karlsson Susanne , Streich Daniel , Rolandini Jensen Alice , Jäger Michael , Becker Hans‐Christian , Bergquist Jonas , Johansson Olof , Hammarström Leif 
Published: January 2010

AbstractThe first examples of rodlike donor–photosensitizer–acceptor arrays based on bis‐2,6‐di(quinolin‐8‐yl)pyridine RuII complexes 1 a and 3 a for photoinduced electron transfer have been synthesized and investigated. The complexes are synthesized in a convergent manner and are isolated as linear, single isomers. Time‐resolved absorption spectroscopy reveals long‐lived, photoinduced charge‐separated states (τCSS (1 a)=140 ns, τCSS (3 a)=200 ns) formed by stepwise electron transfer. The overall yields of charge separation (≥50 % for complex 1 a and ≥95 % for complex 3 a) are unprecedented for bis‐tridentate RuII polypyridyl complexes. This is attributed to the long‐lived excited state of the [Ru(dqp)2]2+ complex combined with fast electron transfer from the donor moiety following the initial charge separation. The rodlike arrangement of donor and acceptor gives controlled, vectorial electron transfer, free from the complications of stereoisomeric diversity. Thus, such arrays provide an excellent system for the study of photoinduced electron transfer and, ultimately, the harvesting of solar energy.
Tertiary Carbinamine Synthesis by Rhodium‐Catalyzed [3+2] Annulation of N‐Unsubstituted Aromatic Ketimines and Alkynes
Authors: Sun Zhong‐Ming , Chen Shuo‐Ping , Zhao Pinjing 
Published: January 2010

AbstractA convenient and waste‐free synthesis of indene‐based tertiary carbinamines by rhodium‐catalyzed imine/alkyne [3+2] annulation is described. Under the optimized conditions of 0.5–2.5 mol % [{(cod)Rh(OH)}2] (cod=1,5‐cyclooctadiene) catalyst, 1,3‐bis(diphenylphosphanyl)propane (DPPP) ligand, in toluene at 120 °C, N‐unsubstituted aromatic ketimines and internal alkynes were coupled in a 1:1 ratio to form tertiary 1H‐inden‐1‐amines in good yields and with high selectivities over isoquinoline products. A plausible catalytic cycle involves sequential imine‐directed aromatic CH bond activation, alkyne insertion, and a rare example of intramolecular ketimine insertion into a RhI–alkenyl linkage.
Step‐by‐Step Synthesis of the Endohedral Stannaspherene [Ir@Sn12]3− via the Capped Cluster Anion [Sn9Ir(cod)]3−
Authors: Wang Jian‐Qiang , Stegmaier Saskia , Wahl Bernhard , Fässler Thomas F. 
Published: January 2010

AbstractThe endohedral stannaspherene cluster anion [Ir@Sn12]3− was synthesized in two steps. The reaction of K4Sn9 with [IrCl(cod)]2 (cod: 1,5‐cyclooctadienyl) in ethylenediamine (en) solution first yielded the [K(2,2,2‐crypt)]+ salt (2,2,2‐crypt: 4,7,13,16,21,24‐hexaoxa‐1,10‐diazabicyclo[8.8.8]hexacosane) of the capped cluster anion [Sn9Ir(cod)]3−. Subsequently, crystals of this compound were dissolved in en, followed by the addition of triphenylphosphine or 1,2‐bis(diphenylphosphino)ethane and treatment at elevated temperatures. [Ir@Sn12]3− was obtained and characterized as the [K(2,2,2‐crypt)]+ salt. The isolation of [Sn9Ir(cod)]3− as an intermediate product establishes that the formation of the stannaspherene [Ir@Sn12]3− occurs through the oxidation of [Sn9Ir(cod)]3−. Among the structurally characterized tetrel cluster anions, [Ir@Sn12]3− is a unique example of a stannaspherene, and one of the rare spherical clusters encapsulating a metal atom that is not a member of Group 10. Single‐crystal structure determination shows that the novel Zintl ion cluster has nearly perfect icosahedral Ih point symmetry.
Catalytic Asymmetric Formation of δ‐Lactones from Unsaturated Acyl Halides
Authors: Tiseni Paolo S. , Peters René 
Published: January 2010

AbstractPreviously unexplored enantiopure zwitterionic ammonium dienolates have been utilized in this work as reactive intermediates that act as diene components in hetero‐Diels–Alder reactions (HDAs) with aldehydes to produce optically active δ‐lactones, subunits of numerous bioactive products. The dienolates were generated in situ from E/Z mixtures of α,β‐unsaturated acid chlorides by use of a nucleophilic quinidine derivative and Sn(OTf)2 as co‐catalyst. The latter component was not directly involved in the cycloaddition step with aldehydes and simply facilitated the formation of the reactive dienolate species. The scope of the cycloaddition was considerably improved by use of a complex formed from Er(OTf)3 and a simple commercially available norephedrine‐derived ligand that tolerated a broad range of aromatic and heteroaromatic aldehydes for a cooperative bifunctional Lewis‐acid‐/Lewis‐base‐catalyzed reaction, providing α,β‐unsaturated δ‐lactones with excellent enantioselectivities. Mechanistic studies confirmed the formation of the dienolate intermediates for both catalytic systems. The active ErIII complex is most likely a monomeric species. Interestingly, all lanthanides can catalyze the title reaction, but the efficiency in terms of yield and enantioselectivity depends directly on the radius of the LnIII ion. Similarly, use of the pseudolanthanides ScIII and YIII also resulted in product formation, whereas the larger LaIII and other transition metal salts, as well as main group metal salts, proved to be inefficient. In addition, various synthetic transformations of 6‐CCl3‐ or 4‐silyl‐substituted α,β‐unsaturated δ‐lactones, giving access to a number of valuable δ‐lactone building blocks, were investigated.
Dye binary mixture formulation by means of derivative ratio spectra of the Kubelka–Munk function
Authors: Nateri A. Shams , Ekrami Ehsan 
Published: January 2010

AbstractIn this study, a new method is introduced for the determination of dye concentration in fabrics dyed with bicomponent dye mixtures. The reflectance spectra of the samples dyed with different binary mixtures of dyes were recorded between 400 and 700 nm. The obtained $ \left ({K\over S}\right )$ spectra were divided by a standard $ \left({K\over S}\right) $ spectrum of each of the components in the mixtures and the derivative spectra were calculated. The amounts of dyes were determined by measurements in suitably selected wavelengths in the acquired derivative ratio spectra. The obtained results indicate that the developed derivative ratio $ \left ({K\over S}\right ) $ spectra method is more accurate than the normal Kubelka–Munk method. The proposed derivative method is simple, accurate, and suitable for quantitative analysis of samples dyed with binary mixed shades. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010
Colour category foci of Munsell colour spectra revealed by two computational methods
Authors: Raisanen Elina , Hauta‐Kasari Markku 
Published: January 2010

AbstractColour names and psychophysical colour categories play an important role on human communication. For several application areas from computer vision to Internet shopping, it would be useful to manage colour information using methods of computational colour naming in a similar manner as people do in their everyday life. In this study, we applied two computational methods, the nonnegative matrix factorization and self‐organizing maps, to derive basic colours from a spectral database of Munsell colours, and a subset of it. The subset was generated to include only the most saturated samples of each Munsell Hue and Munsell Value pair of the original database. Using both the methods and both the databases, we calculated the sets of 3, 4, 6, and 8 basis vectors to represent the focal colours of colour categories. Colour names of the calculated focal colours were investigated using the results by Sturges and Whitfield as a reference. Nonnegative matrix factorization yields calculated colours more compatible with human basic colours, but the spectra generated by self‐organizing maps are more similar to natural spectra as their shape is smoother. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010
Two new von Kries based chromatic adaptation transforms found by numerical optimization
Authors: Bianco S. , Schettini R. 
Published: January 2010

AbstractIn this article, two new von Kries based chromatic adaptation transforms are proposed. The numerical optimization procedure adopted for deriving them simultaneously exploits the whole sets of data available and the existing chromatic adaptation transforms. Experimental results report several statistics to prove the effectiveness of our proposals with respect to the state‐of‐the‐art. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2010
Hemodialysis Adequacy: A Review
Authors: Mehta Ankit N. , Fenves Andrew Z. 
Published: January 2010

Abstract“Adequate dialysis” is interpreted as the amount of dialysis required to keep a patient alive and relatively asymptomatic. Since the inception of hemodialysis, there have been numerous approaches to quantify the delivered dialysis dose in a reproducible manner, and to link the dialysis dose with clinical outcomes.