bluuebunny/crossref_metadata_2025 huggingface dataset:
Introduction: Williams syndrome
Authors: Morris Colleen A.
Published: April 2010

In the nearly 50 years since the description of Williams syndrome by [Williams et al. (1961); Circulation 24:1311–1318], the focus of scientific inquiry has shifted from identification, definition, and description of the syndrome in small series to genotype–phenotype correlation, pathophysiologic investigation in both humans and in animal models, and therapeutic outcomes in large cohorts. Study of this rare syndrome has provided insight into the structure and function of the extracellular matrix, has contributed to understanding of genomic structure and rearrangement, and is beginning to elucidate genetic underpinnings of learning, language, and behavior. The results of current research not only recommend interventions that can be implemented now, but also identify areas requiring additional investigation, and suggest future therapeutic approaches. © 2010 Wiley‐Liss, Inc.
Initiating levodopa/carbidopa therapy with and without entacapone in early Parkinson disease: The STRIDE‐PD study
Authors: Stocchi Fabrizio , Rascol Olivier , Kieburtz Karl , Poewe Werner , Jankovic Joseph , Tolosa Eduardo , Barone Paulo , Lang Anthony E. , Olanow C. Warren
Published: April 2010

Objective

L‐dopa is the most widely used and most effective therapy for Parkinson disease (PD), but chronic treatment is associated with motor complications in the majority of patients. It has been hypothesized that providing more continuous delivery of L‐dopa to the brain would reduce the risk of motor complications, and that this might be accomplished by combining L‐dopa with entacapone, an inhibitor of catechol‐O‐methyltransferase, to extend its elimination half‐life.

Methods

We performed a prospective 134‐week double‐blind trial comparing the risk of developing dyskinesia in 747 PD patients randomized to initiate L‐dopa therapy with L‐dopa/carbidopa (LC) or L‐dopa/carbidopa/entacapone (LCE), administered 4× daily at 3.5‐hour intervals. The primary endpoint was time to onset of dyskinesia.

Results

In comparison to LC, patients receiving LCE had a shorter time to onset of dyskinesia (hazard ratio, 1.29; p = 0.04) and increased frequency at week 134 (42% vs 32%; p = 0.02). These effects were more pronounced in patients receiving dopamine agonists at baseline. Time to wearing off and motor scores were not significantly different, but trended in favor of LCE treatment. Patients in the LCE group received greater L‐dopa dose equivalents than LC‐treated patients (p < 0.001).

Interpretation

Initiating L‐dopa therapy with LCE failed to delay the time of onset or reduce the frequency of dyskinesia compared to LC. In fact, LCE was associated with a shorter time to onset and increased frequency of dyskinesia compared to LC. These results may reflect that the treatment protocol employed did not provide continuous L‐dopa availability and the higher L‐dopa dose equivalents in the LCE group. ANN NEUROL 2010;68:18–27
Magnetically Separable Nanocatalysts: Bridges between Homogeneous and Heterogeneous Catalysis
Authors: Shylesh Sankaranarayanapillai , Schünemann Volker , Thiel Werner R.
Published: April 2010

Recovery and reuse of expensive catalysts after catalytic reactions are important factors for sustainable process management. The aim of this Review is to highlight the progress in the formation and catalytic applications of magnetic nanoparticles and magnetic nanocomposites. Directed functionalization of the surfaces of nanosized magnetic materials is an elegant way to bridge the gap between heterogeneous and homogeneous catalysis. The introduction of magnetic nanoparticles in a variety of solid matrices allows the combination of well‐known procedures for catalyst heterogenization with techniques for magnetic separation.
Effect of the Photoperiod and Administration of Melatonin on the Pars Tuberalis of Viscacha (Lagostomus maximus maximus): An Ultrastructural Study
Authors: Romera Edith Perez , Mohamed Fabian , Fogal Teresa , Dominguez Susana , Piezzi Ramón , Scardapane Luis
Published: April 2010

The pituitary pars tuberalis (PT) is a glandular zone exhibiting well‐defined structural characteristics. Morphologically, it is formed by specific secretory cells, folliculostellate cells, and migratory cells coming from the pars distalis. The purpose of this work was to investigate differences in specific cellular characteristics in the PT of viscachas captured in summer (long photoperiod) and winter (short photoperiod), as well as the effects of chronic melatonin administration in viscachas captured in summer and kept under long photoperiod. In summer, the PT‐specific cells exhibited cell‐like characteristics with an important secretory activity and a moderate amount of glycogen. In winter, the PT‐specific granulated cells showed ultrastructural variations with signs of a reduced synthesis activity. Also, PT showed a high amount of glycogen and a great number of cells in degeneration. After melatonin administration, the ultrastructural characteristics were similar to those observed in winter, but the amount of glycogen was higher. These results suggest possible functional implications as a result of morphological differences between long and short photoperiods, and are in agreement with the variations of the pituitary‐gonadal axis, probably in response to the natural photoperiod changes through the pineal melatonin. The ultrastructural differences observed in PT, after melatonin administration, were similar to those observed in the short photoperiod, thus supporting the hypothesis that these cytological changes are induced by melatonin. Anat Rec, 293:871–878, 2010. © 2010 Wiley‐Liss, Inc.
Synthesis and Characterization of Novel Gold(III) Complexes of Asymmetrically Aryl‐Substituted 1,2‐Dithiolene Ligands Featuring Potential‐Controlled Spectroscopic Properties
Authors: Ambrosio Lucia , Aragoni M. Carla , Arca Massimiliano , Devillanova Francesco A. , Hursthouse Michael B. , Huth Susanne L. , Isaia Francesco , Lippolis Vito , Mancini Annalisa , Pintus Anna
Published: April 2010

The tetrabutylammonium (TBA+) salts of square‐planar monoanionic gold complexes of the unsymmetrically substituted Ar,H‐edt2− 1,2‐dithiolene ligands (Ar,H‐edt2−=arylethylene‐1,2‐dithiolato; Ar=phenyl (1−), 2‐naphthyl (2−), and 1‐pyrenyl (3−)) were synthesized and characterized by spectroscopic and electrochemical methods and the corresponding neutral species (1, 2, and 3, respectively) were obtained in CH2Cl2 solution at room temperature by diiodine oxidation. The single‐crystal X‐ray diffraction structural data collected for (TBA+)(2−), supported by DFT theoretical calculations, are consistent with the ene‐1,2‐dithiolate form of the ligand and the AuIII oxidation state. All complexes feature intense near‐IR absorptions (at about 1.5 μm) in their neutral states and Vis‐emitting properties in the 400–550 nm range, the energy of which is controlled by the charge of the complex in the case of the 3−/3 couple. The spectroscopic and electrochemical features of 1x− and 2x− (x=0, 1), both in their cis and trans conformations, were investigated by means of DFT and time‐dependent (TD) DFT calculations.
The Chemistry of CH Bond Activation on Diamond
Authors: Zhong Yu Lin , Loh Kian Ping
Published: April 2010

The surface of hydrogen‐terminated diamond resembles a solid hydrocarbon substrate. Interestingly, the CH bonds on the diamond surface are not as unreactive as that of saturated hydrocarbon molecules owing to its unique surface electronic properties. The invention of CH bond activation and CC coupling reactions on the diamond surface allows chemists to develop powerful chemical transistors, biosensors, and photovoltaic cells on the diamond platform.
Über die elektrolytische Bestimmung des Nickels in Nitratlösung und seine Trennung vom Kupfer
Authors: Thiel A.
Published: April 2010

Zusammenfassung der Resultate

1 . Nickel lädt sich aus einer von salpetriger Säure befreiten, ammoniakalischen Nitratlösung bei genügendem Ammoniakgehalte quantitativ abscheiden.

2. Platinanoden werden hierbei) sobald sie nicht mehr von einer schützenden Nickeloxydhaut bedeckt sind, stark angegriffen.

3. Die dadurch bedingten Fehler der Analysenmethode lassen sich durch Verwendung passivierter, gerader Eisendrahte als Anoden praktisch beseitigen.

4. Die Endreaktion auf Nickel mit Schwefelammonium ist in stark ammoniakalischer Lösung unzuverlässig. Münster, Chemisches Institut der Universität)
Bücherschau
Authors: Lottermoser  , Meyer Julius
Published: April 2010

Ahrens' Sammlung chemischer und chemisch‐technischer Vorträge, Bd. XII, 4. bis 6. Heft: Neuere Färbetheorien. Von Dr. Karl Schwalbe. Verlag von F. Enke, Stuttgart. 1908.

Kurzes Lehrbuch der organischen Chemie. Von William A. Noyes. Uebersetzt von Walter Ostwald. XXIV und 722 S. Verlag der Akademischen Verlagsgesellschaft m. b. H., Leipzig. 1907.

Fortschritte der Elektrotechnik. Vierteljährliche Berichte über die neueren Erscheinungen auf dem Gesamtgebiete der angewandten Elektrizitätslehre, mit Einschluss des elektrischen Nachrichten‐ und Signalwesens. Im Auftrage und mit Unterstützung des Elektrotechnischen Vereins, sowie mit Unterstützung hervorragender elektrotechnischer Firmen, unter Mitwirkung von Borns, Breisig, Giebe, Grünbaum, Hartenheim, Nösselt, Schneider, Sprenger und Stade herausgegeben von Dr. Karl Strecker. 21. Jahrgang, das Jahr 1907, Heft 3. Verlag von Julius Springer, Berlin 1908. Preis 10 Mk.
Liquid chromatography tandem mass spectrometry method for the quantification of Sarpogrelate, a selective 5‐HT2Areceptor antagonist, in plasma: application to a pre‐clinical pharmacokinetic study
Authors: Nirogi Ramakrishna , Kandikere Vishwottam , Mudigonda Koteshwara , Ajjala Devender , Suraneni Ramakrishna , Thoddi Parthasarathi
Published: April 2010

A simple LC‐MS/MS method was developed and validated for the estimation of sarpogrelate in 50 µL of rat plasma. The analyte and internal standard (IS) were extracted from rat plasma by acetonitrile precipitation and they were separated on a reversed‐phase C8column with gradient program. The MS acquisition was performed with multiple reaction monitoring mode usingm/z430.2 tom/z135.0 for analyte andm/z448.2 tom/z285.3 for IS. The calibration curves were linear over the range of 1–1000 ng/mL with the correlation coefficient greater than 0.999. With dilution integrity up to 20‐fold, the upper limit of quantification was extendable up to 15,000 ng/mL. The method was successfully applied to the analysis of rat plasma samples after single dose oral administration of sarpogrelate at 5 mg/kg to rats for the determination of its pharmacokinetics. Following oral administration the maximum mean concentration in plasma (Cmax, 11514 ng/mL) was achieved at 0.25 h (Tmax) and the area under curve (AUC0–24) was 11051 ± 3315 ng h/mL. The half‐life (t1/2) and clearance (Cl) were 2.9 ± 1.1 h and 490 ± 171 mL/h/kg, respectively. We believe that development of a method in rodent plasma would facilitate the ease of adaptability of sarpogrelate in human plasma. Copyright © 2010 John Wiley & Sons, Ltd.
Sesquiterpene Synthases Cop4 and Cop6 from Coprinus cinereus: Catalytic Promiscuity and Cyclization of Farnesyl Pyrophosphate Geometric Isomers
Authors: Lopez‐Gallego Fernando , Agger Sean A. , Abate‐Pella Daniel , Distefano Mark D. , Schmidt‐Dannert Claudia
Published: April 2010

Sesquiterpene synthases catalyze with different catalytic fidelity the cyclization of farnesyl pyrophosphate (FPP) into hundreds of known compounds with diverse structures and stereochemistries. Two sesquiterpene synthases, Cop4 and Cop6, were previously isolated from Coprinus cinereus as part of a fungal genome survey. This study investigates the reaction mechanism and catalytic fidelity of the two enzymes. Cyclization of all‐trans‐FPP ((E,E)‐FPP) was compared to the cyclization of the cis–trans isomer of FPP ((Z,E)‐FPP) as a surrogate for the secondary cisoid neryl cation intermediate generated by sesquiterpene synthases, which are capable of isomerizing the C2C3 π bond of all‐trans‐FPP. Cop6 is a “high‐fidelity” α‐cuprenene synthase that retains its fidelity under various conditions tested. Cop4 is a catalytically promiscuous enzyme that cyclizes (E,E)‐FPP into multiple products, including (−)‐germacrene D and cubebol. Changing the pH of the reaction drastically alters the fidelity of Cop4 and makes it a highly selective enzyme. Cyclization of (Z,E)‐FPP by Cop4 and Cop6 yields products that are very different from those obtained with (E,E)‐FPP. Conversion of (E,E)‐FPP proceeds via a (6R)‐β‐bisabolyl carbocation in the case of Cop6 and an (E,E)‐germacradienyl carbocation in the case of Cop4. However, (Z,E)‐FPP is cyclized via a (6S)‐β‐bisabolene carbocation by both enzymes. Structural modeling suggests that differences in the active site and the loop that covers the active site of the two enzymes might explain their different catalytic fidelities.
Cloning, Expression and Purification of Cindoxin, an Unusual Fmn‐Containing Cytochrome P450 Redox Partner
Authors: Hawkes David B. , Slessor Kate E. , Bernhardt Paul V. , De Voss James J.
Published: April 2010

Cytochromes P450 (P450s) belong to a superfamily of haemoproteins that catalyse a remarkable variety of oxidative transformations. P450 catalysis generally requires that cognate redox proteins transfer electrons, derived ultimately from NAD(P)H, to the P450 for oxygen activation. P450cin (CYP176A1) is a bacterial P450 that is postulated to allow Citrobacter braakii to live on cineole as its sole carbon source by initiating cineole biodegradation. Here we report the cloning, expression, purification and characterisation of one of its postulated redox partners, cindoxin (Cdx), which has strong similarity to the FMN domain of cytochrome P450 reductase. Cindoxin reductase (CdR), which displays strong similarity to NADPH‐dependent ferredoxin reductases, was unable to be expressed in a functional form. Mass spectrometric and HPLC analyses confirmed that the flavin cofactor of cindoxin was FMN. Redox potentiometric titrations were performed with cindoxin within the range 6<pH<8; this enabled the quinone/semiquinone (E1) and semiquinone/hydroquinone (E2) redox potentials to be determined. Our results show that cindoxin might be somewhat different to other flavodoxins that interact with P450s, in which generally only one couple is important. Both redox states of cindoxin could be catalytically relevant. A catalytically active system was reconstituted in vitro with E. coli flavodoxin reductase (Fpr) acting as the terminal redox partner in the absence of CdR. Our results show that Cdx and Fpr support regio‐ and stereoselective P450cin‐catalysed cineole oxidation to (1R)‐6β‐hydroxycineole with turnover rates up to 1500 min−1. This system is tightly coupled with 80 % of NADPH reducing equivalents funnelled into substrate oxidation.
Design of a Pipe/Ring Type of Sparger for a Bubble Column Reactor
Authors: Kulkarni A. V.
Published: April 2010

The sparger is an important accessory of bubble column reactors which governs the performance of the reactor. Specifically the sparger design becomes more important when the aspect ratio of the bubble column is low. The maldistribution and design of the sparger are of major concern and both these aspects are described in detail in the present work. Various methods for reducing maldistribution have been discussed and a simple method for its reduction is presented experimentally. Further a step‐wise design procedure for a pipe/ring type of sparger for bubble columns is presented together with a work example.
Coexistence of Two Thermally Induced Intramolecular Electron Transfer Processes in a Series of Metal Complexes [M(Cat‐N‐BQ)(Cat‐N‐SQ)]/[M(Cat‐N‐BQ)2] (M=Co, Fe, and Ni) bearing Non‐Innocent Catechol‐Based Ligands: A Combined Experimental and Theoretical Study
Authors: Evangelio Emi , Bonnet Marie‐Laure , Cabañas Miquel , Nakano Motohiro , Sutter Jean‐Pascal , Dei Andrea , Robert Vincent , Ruiz‐Molina Daniel
Published: April 2010

The different thermally induced intermolecular electron transfer (IET) processes that can take place in the series of complexes [M(Cat‐N‐BQ)(Cat‐N‐SQ)]/[M(Cat‐N‐BQ)2], for which M=Co (2), Fe (3) and Ni(4), and Cat‐N‐BQ and Cat‐N‐SQ denote the mononegative (Cat‐N‐BQ−) or dinegative (Cat‐N‐SQ2−) radical forms of the tridentate Schiff‐base ligand 3,5‐di‐tert‐butyl‐1,2‐quinone‐1‐(2‐hydroxy‐3,5‐di‐tert‐butylphenyl)imine, have been studied by variable‐temperature UV/Vis and NMR spectroscopies. Depending on the metal ion, rather different behaviors are observed. Complex 2 has been found to be one of the few examples so far reported to exhibit the coexistence of two thermally induced electron transfer processes, ligand‐to‐metal (IETLM) and ligand‐to‐ligand (IETLL). IETLL was only found to take place in complex 3, and no IET was observed for complex 4. Such experimental studies have been combined with ab initio wavefunction‐based CASSCF/CASPT2 calculations. Such a strategy allows one to solicit selectively the speculated orbitals and to access the ground states and excited‐spin states, as well as charge‐transfer states giving additional information on the different IET processes.
Peptide Nanofibers Modified with a Protein by Using Designed Anchor Molecules Bearing Hydrophobic and Functional Moieties
Authors: Miyachi Ayaka , Takahashi Tsuyoshi , Matsumura Sachiko , Mihara Hisakazu
Published: April 2010

Self‐assembly of peptides and proteins is a key feature of biological functions. Short amphiphilic peptides designed with a β‐sheet structure can form sophisticated nanofiber structures, and the fibers are available as nanomaterials for arranging biomolecules. Peptide FI (H‐PKFKIIEFEP‐OH) self‐assembles into nanofibers with a coiled fine structure, as reported in our previous work. We have constructed anchor molecules that have both a binding moiety for the fiber structure and a functional unit capable of capturing target molecules, with the purpose of arranging proteins on the designed peptide nanofibers. Designed anchors containing an alkyl chain as a binding unit and biotin as a functional moiety were found to bind to peptide fibers FI and F2i (H‐ALEAKFAAFEAKLA‐NH2). The surface‐exposed biotin moiety on the fibers could capture an anti‐biotin antibody. Moreover, hydrophobic dipeptide anchor units composed of iminodiacetate connected to Phe–Phe or Ile–Ile and a peptide composed of six histidine residues connected to biotin could also connect FI peptide fibers to the anti‐biotin antibody through the chelation of Ni2+ ions. This strategy of using designed anchors opens a novel approach to constructing nanoscale protein arrays on peptide nanomaterials.
Bipyridyl Derivatives as Photomemory Devices: A Comparative Electronic‐Structure Study
Authors: Ortiz‐Sánchez Juan Manuel , Gelabert Ricard , Moreno Miquel , Lluch José M. , Anglada Josep M. , Bofill Josep M.
Published: April 2010

The two isoelectronic bipyridyl derivatives [2,2′‐bipyridyl]‐3,3′‐diamine (BP(NH2)2) and [2,2′‐bipyridyl]‐3,3′‐diol (BP(OH)2) are experimentally known to undergo very different excited‐state double proton transfer processes that result in fluorescence quantum yields that differ by four orders of magnitude. Such differences have been theoretically explained in terms of topographical features in the potential energy surface and the likely presence of conical intersections. The hypothetical hybrid compound [2,2′‐bipyridyl]‐3‐amin‐3′‐ol (BP(OH)(NH2)) presents intermediate photochemical features of its “ancestors”. In this report we analyze the photochemical properties of a whole family of “dark” (not fluorescent) states that can be accessed from each bipyridyl derivative upon irradiation of light of a given wavelength and their potential application as photomemory devices. In the light of our density functional theory (DFT), time‐dependent DFT (TDDFT), and complete active space self‐consistent field (CASSCF) calculations, BP(NH2)2 is the more likely candidate to become a photomemory device.
Ir‐Catalysed Asymmetric Allylic Substitutions with Cyclometalated (Phosphoramidite)Ir Complexes—Resting States, Catalytically Active (π‐Allyl)Ir Complexes and Computational Exploration
Authors: Raskatov Jevgenij A. , Spiess Stephanie , Gnamm Christian , Brödner Kerstin , Rominger Frank , Helmchen Günter
Published: April 2010

Mechanistic aspects of allylic substitutions with iridium catalysts derived from phosphoramidites by cyclometalation were investigated. The determination of resting states by 31P NMR spectroscopy led to the conclusion that the cyclometalation process is reversible. A novel, one‐pot procedure for the preparation of (π‐ allyl)Ir complexes was developed, and these complexes were characterised by X‐ray crystal structure analyses and spectral data. They are fully active catalysts of the allylic substitution reaction. DFT calculations on the allyl complexes, transition states of the allylic substitution and product olefin complexes gave further mechanistic insight.
Methane Activation by Platinum: Critical Role of Edge and Corner Sites of Metal Nanoparticles
Authors: Viñes Francesc , Lykhach Yaroslava , Staudt Thorsten , Lorenz Michael P. A. , Papp Christian , Steinrück Hans‐Peter , Libuda Jörg , Neyman Konstantin M. , Görling Andreas
Published: April 2010

Complete dehydrogenation of methane is studied on model Pt catalysts by means of state‐of‐the‐art DFT methods and by a combination of supersonic molecular beams with high‐resolution photoelectron spectroscopy. The DFT results predict that intermediate species like CH3 and CH2 are specially stabilized at sites located at particles edges and corners by an amount of 50–80 kJ mol−1. This stabilization is caused by an enhanced activity of low‐coordinated sites accompanied by their special flexibility to accommodate adsorbates. The kinetics of the complete dehydrogenation of methane is substantially modified according to the reaction energy profiles when switching from Pt(111) extended surfaces to Pt nanoparticles. The CH3 and CH2 formation steps are endothermic on Pt(111) but markedly exothermic on Pt79. An important decrease of the reaction barriers is observed in the latter case with values of approximately 60 kJ mol−1 for first CH bond scission and 40 kJ mol−1 for methyl decomposition. DFT predictions are experimentally confirmed by methane decomposition on Pt nanoparticles supported on an ordered CeO2 film on Cu(111). It is shown that CH3 generated on the Pt nanoparticles undergoes spontaneous dehydrogenation at 100 K. This is in sharp contrast to previous results on Pt single‐crystal surfaces in which CH3 was stable up to much higher temperatures. This result underlines the critical role of particle edge sites in methane activation and dehydrogenation.
Cross‐Coupling/Cyclization Reactions of Two Different Allenic Moieties
Authors: Alcaide Benito , Almendros Pedro , Martínez del Campo Teresa
Published: April 2010

The allene moiety represents an excellent building block for allene cross‐coupling cyclization reactions, affording heterocyclic skeletons in a single step. This strategy is of particular interest when two different allene derivatives are involved in a series of metal‐catalyzed cross‐coupling heterocyclization processes. This Concept article is focused on the Pd‐catalyzed union of two different allenic moieties, with cyclization of at least one of them by intramolecular cyclometalation. These new, versatile, and highly effective transformations are complex multistep processes leading to potential privileged structures that could find wide applications in related medicinal chemistry.
Nanoparticle transport in a realistic model of the tracheobronchial region
Authors: Comerford A. , Bauer G. , Wall W. A.
Published: April 2010

The transport and deposition of nanoparticles in the human lung has important health consequences for both hazardous and non‐hazardous reasons. Example scenarios are inhalation of toxic pollutants from the surrounding environment and novel targeted drug delivery to the lung epithelial surface. In this paper, we develop a method to simulate the time‐dependent transport of nanoparticles in CT‐based models of the human tracheobronchial region. We consider the transport in a seven generation model based on an Euler–Euler approach for particles ranging from 1.5 to 11 nm, i.e. in a range considered important for the tracheobronchial region. The results indicate that the deposition of smaller particles are affected more by the non‐uniformity of the realistic geometry. In particular, we observe spatial variations in wall deposition directly resulting from the complex air flow patterns. Time‐dependent effects tend to be less significant compared with the geometric effects. Copyright © 2010 John Wiley & Sons, Ltd.
Distributed reachability testing of concurrent programs
Authors: Carver Richard H. , Lei Yu
Published: April 2010

Reachability testing is an approach to verifying concurrent programs. During reachability testing, every partially ordered synchronization sequence of a program with a given input is exercised exactly once. In this paper, we present the design and implementation of a distributed reachability testing algorithm for a cluster of workstations. This algorithm allows different test sequences to be exercised concurrently by different workstations without any synchronization, and without any duplication of sequences among workstations. Dynamic load balancing is performed using a work‐stealing scheme. A novel aspect of this scheme is that work‐stealing requests progress in rounds. This round‐based structure identifies overloaded workstations to target for work stealing. Empirical studies show good speedup for four benchmark Java programs and one Lotos specification. Copyright © 2010 John Wiley & Sons, Ltd.
Global‐scale distributed I/O with ParaMEDIC
Authors: Balaji P. , Feng W. , Lin H. , Archuleta J. , Matsuoka S. , Warren A. , Setubal J. , Lusk Ewing , Thakur R. , Foster I. , Katz D. S. , Jha S. , Shinpaugh K. , Coghlan S. , Reed D.
Published: April 2010

Achieving high performance for distributed I/O on a wide‐area network continues to be an elusive holy grail. Despite enhancements in network hardware as well as software stacks, achieving high‐performance remains a challenge. In this paper, our worldwide team took a completely new and non‐traditional approach to distributed I/O, calledParaMEDIC: Parallel Metadata Environment for Distributed I/O and Computing, by utilizing application‐specifictransformationof data to orders of magnitude smaller metadata before performing the actual I/O. Specifically, this paper details our experiences in deploying a large‐scale system to facilitate the discovery of missing genes and constructing a genome similarity tree by encapsulating the mpiBLAST sequence‐search algorithm into ParaMEDIC. The overall project involved nine computational sites spread across the U.S. and generated more than a petabyte of data that was ‘teleported’ to a large‐scale facility in Tokyo for storage. Copyright © 2010 John Wiley & Sons, Ltd.
Optimization of process parameters by Taguchi method in the recovery of lactose from whey using sonocrystallization
Authors: Patel S. R. , Murthy Z. V. P.
Published: April 2010

Anti‐solvent crystallization of lactose in the presence of ultrasound will reduce crystal size and the level of agglomeration as compared to the commercial cooling crystallization. It offers a potential route to enhance the physical properties as well as the rapid recovery of lactose. Since lactose recovery itself can reduce biological oxygen demand of whey by more then 80%, recovery of lactose from dairy waste stream (whey) solves the problems of dairy industries by improving economics of whey utilization and pollution reduction. In the present study, recovery of lactose from partially deproteinated whey using an anti‐solvent (acetone) by sonocrystallization was optimized for finding the most influencing operating parameters; such as sonication time, anti‐solvent concentration, initial lactose concentration in the whey and initial pH of sample mixture at three levels using L9‐orthogonal method. The responses were analyzed for recovery of lactose from whey. The anti‐solvent concentration and the sonication time were found to be most influencing parameters for the recovery of lactose and the recovery of lactose was found to be 89.03% at the identified optimized level. The crystal size distribution of recovered lactose was found to be narrower (2.5 – 6.5 μm) as compared to the commercial lactose crystals (3.5 – 9.5 μm). (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermal transformations of the mineral component of composite biomaterials based on chitosan and apatite
Authors: Danilchenko S. N. , Kalinkevich O. V. , Kuznetsov V. N. , Kalinkevich A. N. , Kalinichenko T. G. , Poddubny I. N. , Starikov V. V. , Sklyar A. M. , Sukhodub L. F.
Published: April 2010

Composite biomaterials based on chitosan and calcium apatite with different chitosan/apatite ratio were prepared by chemical synthesis of apatite in chitosan solution using one‐step co‐precipitation method. Initial and annealed samples were characterized by X‐ray diffraction, FTIR spectroscopy and scanning electron microscopy coupled to energy‐dispersive electron X‐ray spectroscopy. The data obtained suggest that the formation of the calcium‐phosphate mineral in chitosan solution is substantially modulated by the chemical interaction of the components; apparently, a part of calcium is captured by chitosan and does not participate in the formation of the main mineral phase. The apatite in the composite is calcium‐deficient, carbonate‐substituted and is composed of dispersed nano‐sized crystallites, i.e. has properties that closely resemble those of bone mineral. Varying synthesis, drying and lyophilization conditions, the composite materials can be produced with the desirable chitosan/apatite ratio, both in the dense and porous form. The structural analysis of composite samples after annealing at certain temperatures is examined as an approach to elucidate the mechanism of co‐precipitation by one‐step method. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Altered vascular expression of EphrinB2 and EphB4 in a model of oxygen‐induced retinopathy
Authors: Davies Michael H. , Stempel Andrew J. , Hubert Kristin E. , Powers Michael R.
Published: April 2010

EphrinB2 ligands and EphB4 receptors are expressed on endothelial cells (EC) of arteries and veins, respectively, and are essential for vascular development. To understand how these molecules regulate retinal neovascularization (NV), we evaluated their expression in a model of oxygen‐induced retinopathy (OIR). EphrinB2 and EphB4 were expressed on arterial and venous trunks, respectively, and on a subset of deep capillary vessels. EphB4 expression was reduced following hyperoxia, while ephrinB2 expression remained unaltered. In addition, a subset of EphB4‐positive veins regressed in a caspase‐3‐dependent manner during hyperoxia. Arteriovenous malformations were also observed with loss of arterial‐venous boundaries. Finally, both ephrinB2 and EphB4 were expressed on a subset of neovascular tufts following hyperoxia. These data confirm the contribution of ECs from both venous and arterial origins to the development of retinal NV. Developmental Dynamics 239:1695–1707, 2010. © 2010 Wiley‐Liss, Inc.
Permanent Encapsulation or Host–Guest Behavior of Aromatic Molecules in Hexanuclear Arene Ruthenium Prisms
Authors: Freudenreich Julien , Barry Nicolas P. E. , Süss‐Fink Georg , Therrien Bruno
Published: April 2010

Cationic arene ruthenium metallaprisms of the general formula [Ru6(p‐cymene)6(tpt)2(OO∩OO)3]6+ {tpt = 2,4,6‐tris(4‐pyridyl)‐1,3,5‐triazine; OO∩OO = 9,10‐dioxo‐9,10‐dihydroanthracene‐1,4‐diolato [1]6+, 6,11‐dioxo‐6,11‐dihydronaphthacene‐5,12‐diolato [2]6+} have been obtained from the corresponding dinuclear arene ruthenium complexes [Ru2(p‐cymene)2(OO∩OO)Cl2] by reaction with tpt and silver trifluoromethanesulfonate. Aromatic molecules (phenanthrene, pyrene, triphenylene, coronene) present during the synthesis of these metallaprisms are permanently encapsulated to give carceplex systems. All empty cages ([1]6+ and [2]6+) and carceplex systems ([guest⊂1]6+ and [guest⊂2]6+) were isolated in good yield as trifluoromethanesulfonate salts and characterized by NMR, UV, and IR spectroscopy. The host–guest properties of [1]6+ and [2]6+ were studied in solution in the presence of small aromatic molecules (phenanthrene andpyrene). The stability constant of association (Ka) wasestimated by NMR spectroscopy for the following host–guest systems: [phenanthrene⊂1]6+, [pyrene⊂1]6+ and [phenanthrene⊂2]6+, [pyrene⊂2]6+. All Ka values were found to be larger than 2.0 × 104 M–1 for these host–guest systems ([D3]acetonitrile, 21 °C).
SOFA database temporarily out of order
Authors: Aitzetmüller Kurt
Published: April 2010

Readers are informed about temporary problems with the database “Seed Oil Fatty Acids” (SOFA). Because industrial oil crops with unusual fatty acids are currently a hot research field, many requests for information reached the author, particularly often from ICON‐Partners worldwide (http://icon.slu.se/ICON/Part icon.htm). SOFA should be online again later in 2010. The nature of SOFA and some potential applications of SOFA are briefly discussed.
Evaluation of the performance of single‐walled carbon nanohorns in capillary electrophoresis
Authors: Jiménez‐Soto Juan Manuel , Moliner‐Martínez Yolanda , Cárdenas Soledad , Valcárcel Miguel
Published: April 2010

This paper describes for the first time the use of single‐walled carbon nanohorns (SWNHs) as pseudostationary and stationary phases for EKC and CEC, respectively, taking advantage of their characteristic features, such as conical‐end termination, formation of spherical assemblies dahlia‐flower like superstructure and easy functionalization. The use of SWNHs as pseudostationary phase for EKC required the study of their dispersion in different surfactants as well as their compatibility with the electrophoretic system. The carboxylation and subsequent immobilization of carboxylated SWNHs in fused‐silica capillary to obtain useful, reproducible and stable stationary phases for CEC has also been investigated, with promising results. The electrophoretic separations obtained for water‐soluble vitamins in both modalities (EKC and CEC) have been systematically compared with those obtained with single‐walled carbon nanotubes.
Highly sensitive non‐isotopic restriction endonuclease fingerprinting of nucleotide variability in the gp60 gene within Cryptosporidium species, genotypes and subgenotypes infective to humans, and its implications
Authors: Pangasa Aradhana , Jex Aaron R. , Nolan Matthew J. , Campbell Bronwyn E. , Haydon Shane R. , Stevens Melita A. , Gasser Robin B.
Published: April 2010

The high‐resolution analysis of genetic variation has major implications for the identification of parasites and micro‐organisms to species and subspecies as well as for population genetic and epidemiological studies. In this study, we critically assessed the effectiveness of a PCR‐based restriction endonuclease fingerprinting (REF) method for the detection of mutations in the 60 kDa glycoprotein gene (gp60) of Cryptosporidium, a genus of parasitic protists of major human and animal health importance globally. This gene displays substantial intraspecific variability in sequence, particularly in a TCA (perfect and imperfect) microsatellite region, is present as a single copy in the nuclear genome and is used widely as a marker in molecular epidemiological studies of Cryptosporidium hominis and C. parvum, the two predominant species that infect humans. The results of this study demonstrated an exquisite capacity of REF to detect nucleotide variability in the gp60 gene within each of the two species. The differentiation of genotypes/subgenotypes based on REF analysis was supported by targeted sequencing, allowing the detection of levels of variation as low as a single‐nucleotide transversion for amplicons of ∼1 kb in size. The high‐throughput potential and relatively low‐cost of REF make it a particularly useful tool for large‐scale genetic analyses of C. hominis and C. parvum. REF could also be utilized for comparative surveys of genetic variability across large nuclear genomic regions. Such analyses of Cryptosporidium in clinical and environmental samples by REF have important implications for identifying sources of infection, modes of transmission and/or possible infectivity to humans, thus assisting in the surveillance and control of cryptosporidiosis. Given its excellent mutation detection capacity, REF should find broad applicability to various single‐copy genes as well as a wide range of other protozoan and metazoan parasites. (The nucleotide sequences reported in this article are available in the GenBank database under accession numbers GU214343–GU214371).
Holocene flood histories in south‐western USA
Authors: Harden Tessa , Macklin Mark G. , Baker Victor R.
Published: April 2010

River basins in south‐western USA are some of the most extensively studied arid land fluvial systems in the world. Since the early 1960s their hydro‐climatic histories have been reconstructed from the analysis of alluvial cut‐and‐fill cycles, while from the late 1970s there have been investigations of slackwater deposits and palaeostage indicators for large floods in stable‐boundary bedrock reaches. However, no studies have regionally integrated Holocene fluvial histories from these two different types of fluvial environments. The current study combines the alluvial archive with flood records from bedrock reaches to generate a probability‐based 12,000 year record of flooding in south‐western USA. Using more than 70014C‐dated fluvial units, the analysis produces a high resolution (centennial) flood record. Seven episodes of increased flooding occurred at 11,250–10,400, 8800–8350, 8230–7600, 6700–5700, 5600–4820, 4550–3320 and 2000–0 cal. BP. Bedrock reaches are found to record more frequent floods during the middle to late Holocene, while in alluvial rivers more flood units are dated to the early and middle Holocene. These differences are primarily the result of selective preservation with alluvial reaches tending to erode during periods characterised by very large floods. Episodes of major Holocene flooding recorded in slackwater deposits within bedrock systems correspond with periods of increased precipitation in the region and lower temperatures. In contrast, within alluvial rivers above‐average flooding probabilities, as well as regionally extensive channel entrenchment episodes, match with reduced annual precipitation and lower temperatures. The results of this study clearly demonstrate the value of the Holocene fluvial archive for reconstructing regional, short‐term hydro‐climatic change in south‐western USA. Copyright © 2010 John Wiley & Sons, Ltd.
Mixed‐order interpolation for the Galerkin coarse‐grid approximations in algebraic multigrid solvers
Authors: Webster R.
Published: April 2010

An empirical investigation is made of AMG solver performance for the fully coupled set of Navier–Stokes equations. The investigation focuses on two different FV discretizations for the standard driven cavity test problem. One is a collocated vertex‐based discretization; the other is a cell‐centred staggered‐grid discretization. Both employ otherwise identical orthogonal Cartesian meshes. It is found that if mixed‐order interpolation is used in the construction of the Galerkin coarse‐grid approximation (CGA), a close‐to‐optimum mesh‐independent scaling of the AMG convergence is observed with similar convergence rates for both discretizations.

If, on the other hand, an equal‐order interpolation is used, convergence rates are mesh‐dependent but the scaling differs in each case. For the collocated‐grid case, it depends both on the mesh size, h (or bandwidth Q∼h−1) and on the total number of grids, G, whereas for the staggered‐grid case it depends only on Q. Comparing the two characteristics reveals that the Q‐dependent parts are very similar; it is only in the G‐dependent convergence for the collocated‐grid case that they differ. This takes the form of stepped reductions in the AMG convergence rate (implying step reductions in the quality of the Galerkin CGA that correlate exactly with step increases in G).

These findings reinforce previous evidence that, for optimum mesh‐independent performance, mixed‐order interpolations should be used in forming Galerkin CGAs for coupled Navier–Stokes problems. Copyright © 2010 John Wiley & Sons, Ltd.
Primary human osteoblast culture on 3D porous collagen‐hydroxyapatite scaffolds
Authors: Jones Gemma L. , Walton Robin , Czernuszka Jan , Griffiths Sarah L. , El Haj Alicia J. , Cartmell Sarah H.
Published: April 2010

There is a need in tissue‐engineering for 3D scaffolds that mimic the natural extracellular matrix of bone to enhance cell adhesion, proliferation, and differentiation. The scaffold is also required to be degradable. A highly porous scaffold has been developed to incorporate two of the extracellular components found in bone—collagen and hydroxyapatite (HA). The scaffold's collagen component is an afibrillar monomeric type I atelocollagen extracted from foetal calf's skin. This provided a novel environment for the inclusion of HA powder. Five hundred thousand primary human osteoblasts were seeded onto 4 mm cubed scaffolds that varied in ratio of HA to collagen. Weight ratios of 1:99, 25:75, 50:50, and 75:25 hydroxyapatite:collagen (HA:Collagen) were analysed. The scaffolds plus cells were cultured for 21 days. DNA assays and live/dead viability staining demonstrated that all of the scaffolds supported cell proliferation and viability. An alkaline phosphatase assay showed similar osteoblast phenotype maintenance on all of the 3D scaffolds analysed at 21 days. MicroCT analysis demonstrated an increase in total sample volume (correlating to increase in unmineralised matrix production). An even distribution of HA throughout the collagen matrix was observed using this technique. Also at 3 weeks, reductions in the percentage of the mineralised phase of the constructs were seen. These results indicate that each of the ratios of HA/collagen scaffolds have great potential for bone tissue engineering. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2010.
Fyn promotes phosphorylation of collapsin response mediator protein 1 at tyrosine 504, a novel, isoform‐specific regulatory site
Authors: Buel Gwen R. , Rush John , Ballif Bryan A.
Published: April 2010

In vertebrates the collapsin response mediator proteins (CRMPs) are encoded by five highly related genes. CRMPs are cytosolic phosphoproteins abundantly expressed in developing and mature mammalian brains. CRMPs are best understood as effectors of Semaphorin 3A signaling regulating growth cone collapse in migratory neurons. Phosphorylation in the carboxyl‐terminal regulatory domain of CRMPs by several serine/threonine kinases has been described. These phoshorylation events appear to function, at least in part, to disrupt the interaction of CRMPs with tubulin heterodimers. In a large‐scale phosphoproteomic analysis of murine brain, we recently identified a number of in vivo tyrosine phosphorylation sites on CRMP isoforms. Using biochemical approaches and quantitative mass spectrometry we demonstrate that one of these sites, CRMP1 tyrosine 504 (Y504), is a primary target of the Src family of tyrosine kinases (SFKs), specifically Fyn. Y504 is adjacent to CDK5 and GSK‐3β sites that regulate the interaction of CRMPs with tubulin. Although Y504 is highly conserved among vertebrate CRMP1 orthologs, a residue corresponding to Y504 is absent in CRMP isoforms 2–5. This suggests an isoform‐specific regulatory role for CRMP1 Y504 phosphorylation and may help explain the observation that CRMP1‐deficient mice exhibit neuronal migration defects not compensated for by CRMPs 2–5. J. Cell. Biochem. 111: 20–28, 2010. © 2010 Wiley‐Liss, Inc.
Antagonistic interplay between mechanical forces and glucocorticoids in bone: A tale of kinases
Authors: Bellido Teresita
Published: April 2010

The contrasting actions of mechanical forces and glucocorticoids (GC) on bone have been long recognized. However, the cellular and molecular mechanisms by which these stimuli impact the skeleton remain only partially known. Recent evidence gained from studies on bone cell apoptosis has revealed that mechanical forces and GC exhibit converse effects on osteocyte and osteoblast survival resulting from divergent actions on the focal adhesion kinases FAK and Pyk2, molecules that regulate integrin‐dependent interactions between bone cells and the extracellular matrix (ECM). This prospect reviews these findings and poses the possibility that similar opposing effects on kinase signaling are responsible for other actions of mechanical forces and GC on the skeleton, in particular on bone formation and the Wnt signaling pathway. J. Cell. Biochem. 111: 1–6, 2010. © 2010 Wiley‐Liss, Inc.
Transmembrane 4 L six family member 5 (TM4SF5) enhances migration and invasion of hepatocytes for effective metastasis
Authors: Lee Sin‐Ae , Kim Tae You , Kwak Tae Kyoung , Kim Hyeonjung , Kim Semi , Lee Hyo Jeong , Kim Sung‐Hoon , Park Ki Hun , Kim Hyun Jeong , Cho Moonjae , Lee Jung Weon
Published: April 2010

Overexpression of transmembrane 4 L six family member 5 (TM4SF5), a four‐transmembrane L6 family member, causes aberrant cell proliferation and angiogenesis, but the roles of TM4SF5 in migration, invasion, and tumor metastasis remain unknown. Using in vitro hepatocarcinoma cells that ectopically or endogenously express TM4SF5 and in vivo mouse systems, roles of TM4SF5 in metastatic potentials were examined. We found that TM4SF5 expression facilitated migration, invadopodia formation, MMP activation, invasion, and eventually lung metastasis in nude mice, but suppression of TM4SF5 with its shRNA blocked the effects. Altogether, TM4SF5‐mediated migration and invasion suggest that TM4SF5 may be therapeutically targeted to deal with TM4SF5‐mediated hepatocellular cancers. J. Cell. Biochem. 111: 59–66, 2010. © 2010 Wiley‐Liss, Inc.
Localization of nucleophosmin in nuclear matrix and changes in its expression during the differentiation of human neuroblastoma induced by retinoic acid
Authors: Shi Song‐Lin , Liang Ying , Li Qi‐Fu , Liu Qing‐Rong , Jing Guang‐Jun , Wang San‐Ying , Zhang Xiu‐Yan , Wu Fu‐Yun
Published: April 2010

In this article, we selectively extracted the nuclear matrix and intermediate filament system of human neuroblastoma SK‐N‐SH cells pre‐ and post‐treated with retinoic acid (RA). The distribution of nucleophosmin (NPM) in the nuclear matrix and its colocalization with several products of related genes were investigated. Results from two‐dimensional gel electrophoresis and MALDI‐TOF showed that NPM was a component of the nuclear matrix and its expression in SK‐N‐SH cells post‐treated with RA was down‐regulated. Immunofluorescent microscopy observations further showed that NPM was localized in the nuclear matrix of SK‐N‐SH cells, and its expression level and distribution were altered after treatment with RA. The colocalization of NPM with c‐myc, c‐fos, p53, and Rb in SK‐N‐SH cells was observed under a laser scanning confocal microscope, but the colocalization region was changed by RA. Our results prove that NPM is a nuclear matrix protein, which is localized in nuclear matrix fibers. The colocalization of NPM with its related genes and oncogenes affect the differentiation of SK‐N‐SH cells. The expression of NPM and its distribution in the process of cell differentiation deserve more intensive investigation. J. Cell. Biochem. 111: 67–74, 2010. © 2010 Wiley‐Liss, Inc.