bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of human muscle stem cells reveals a differentiation‐resistant progenitor cell population expressing Pax7 capable of self‐renewal
Authors: Pawlikowski Bradley , Lee Laimeng , Zuo Jianhong , Kramer Randall H. 
Published: December 2008

AbstractStudies using mouse models have established a critical role for resident satellite stem cells in skeletal muscle development and regeneration, but little is known about this paradigm in human muscle. Here, using human muscle stem cells, we address their lineage progression, differentiation, migration, and self‐renewal. Isolated human satellite cells expressed α7‐integrin and other definitive muscle markers, were highly motile on laminin substrates and could undergo efficient myotube differentiation and myofibrillogenesis. However, only a subpopulation of the myoblasts expressed Pax7 and displayed a variable lineage progression as measured by desmin and MyoD expression. Analysis identified a differentiation‐resistant progenitor cell population that was Pax7+/desmin− and capable of self‐renewal. This study extends our understanding of the role of Pax7 in regulating human satellite stem cell differentiation and self‐renewal. Developmental Dynamics 238:138–149, 2009. © 2008 Wiley‐Liss, Inc.
Indenylidene Complexes of Ruthenium Bearing NHC Ligands – Structure Elucidation and Performance as Catalysts for Olefin Metathesis
Authors: Monsaert Stijn , De Canck Els , Drozdzak Renata , Van Der Voort Pascal , Verpoort Francis , Martins José C. , Hendrickx Pieter M. S. 
Published: December 2008

AbstractSecond‐generation catalysts of the general formula Cl2Ru(SIMes)(L)(3‐phenylinden‐1‐ylidene), 3a (L = PCy3), 3b (L = PPh3), 3c (L = py), and Cl2Ru(SIMe)(L)(3‐phenylinden‐1‐ylidene), 4a (L = PCy3), 4b (L = PPh3), 4c (L = py) were found to be of interest in various metathesis transformations. The catalysts containing SIMe ligands showed improved initiation compared to the more robust SIMes substituted catalysts. A strong temperature effect was noted on all of the reactions tested. Interestingly, complex 3a, showing the lowest initiation rate at room temperature, emerged as the most productive of all systems examined at elevated temperature. It is shown that complexes containing the SIMe ligand display higher initiation efficiency than their corresponding SIMes analogues. Since the higher initiation is related to the ease of phosphane dissociation while phosphane dissociation also promotes catalyst decomposition, complexes bearing the SIMe ligand decompose faster. The complete 1H, 13C and 31P resonance assignment and the procedure applied to obtain these from a combination of 1D and 2D NMR techniques, is also reported. Combined with the ROESY technique, these enabled to investigate several conformational processes involving rotations around N–phenyl and C–Ru bonds on the millisecond to second timescale. A clear correlation is demonstrated between the bulkiness of the axial ligand (L) and the rotational freedom of the SIMe(s) ligand. A qualitative analysis also suggests that the extra para‐methyl of SIMes leads to additional steric interactions with the 3‐phenylinden‐1‐ylidene ligand. The data reported in this paper demonstrates that substitution patterns of the N‐aryl have a significant influence on the activity of the second‐generation indenylidene catalysts for a given metathesis reaction.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Photoelectrocatalytic Oxidation of NADH at a Graphite Electrode Modified with a New Polymeric Phenothiazine
Authors: Gligor Delia , Dilgin Yusuf , Popescu Ionel Catalin , Gorton Lo 
Published: December 2008

AbstractA new approach for photoelectrocatalytic oxidation of NADH is described, based on a graphite electrode (G) modified with a new phenothiazine derivative, polyphenothiazine formaldehyde (PPF). Electrochemical measurements reveal that G/PPF presents a quasireversible voltammetric response, corresponding to a 2e−/2H+ transfer and that G/PPF modified electrodes show electrocatalytic activity for NADH oxidation. When the surface of the G/PPF modified electrode was irradiated with a light source (250 W Halogen lamp), a significant increase in the electrocatalytic current was observed. The second order electrocatalytic rate constant (kobs, [NADH]=0=3.9×103 M−1 s−1, pH 7.0) was calculated from rotating disk electrode experiments, performed at various NADH concentrations. From amperometric measurements, it was noticed that, in the presence of light irradiation, the sensitivity of NADH detection (calculated as Imax/KM ratio) increased ca. 3 times.
An M&A lesson: Should money always talk?
Authors: Tokic Stijepko , Beyea Genevieve 
Published: December 2008

AbstractThe recent economic downturn has caused a shake‐up in the private equity markets—with important implications for mergers and acquisitions (M&As). One recent merger agreement—once lauded as exemplary—has disintegrated into four separate, contentious lawsuits. What went wrong there? And what lessons does it hold to prevent similar disasters in the future? © 2009 Wiley Periodicals, Inc.
Merging financial and managerial accounting: Strategic cost management and enterprise risk assessment under SOX
Authors: Shank John K. , Miguel Joseph G. San 
Published: December 2008

AbstractThe spate of accounting and financial reporting scandals in recent years has challenged businesses, auditors, directors, and accounting regulators to take a much broader perspective in evaluating and reporting on risk. The Sarbanes‐Oxley (SOX) legislation in the United States was an attempt to address the problems by requiring enterprises to assess their risks. This article examines the eventful life of an entrepreneurial, publicly traded U.S. telecom venture, including its efforts to support the “strategic enterprise” perspective. It points out the dangers when this perspective is ignored. © 2009 Wiley Periodicals, Inc.
Role‐reversal of gender‐associated mitochondrial DNA affects mitochondrial function in Mytilus edulis (Bivalvia: Mytilidae)
Authors: Breton Sophie , Stewart Donald T. , Blier Pierre U. 
Published: December 2008

AbstractMussel species of the genus Mytilus possess an unusual system of mitochondrial DNA (mtDNA) transmission termed doubly uniparental inheritance. They are characterized by the presence of two highly divergent gender‐associated mtDNA genomes (often with>20 and>10% divergences in DNA and amino acid sequences, respectively) that are inherited either maternally (F mtDNA) or paternally (M mtDNA). Females are typically homoplasmic for the F mtDNA and males are heteroplasmic with the F mtDNA being most common in all tissues except the gonad that is dominated by the M mtDNA. Collectively, males are polymorphic for two classes of M mtDNAs known as the “standard male” and “recently masculinized” M types (SM and RM, respectively). The coding portions of the RM mtDNA genome differ from the SM mtDNA by as much as the maternally inherited F mtDNA genome differs from the SM type. Because the SM and RM types exhibit considerable amino acid sequence divergence, we hypothesized that these differences could affect mitochondrial respiratory chain complex enzyme activities. To test this hypothesis, the activity of the major mitochondrial respiratory chain complexes (complexes II, I+III and IV) as well as the activity of citrate synthase were measured on gonad samples from males containing either the SM or RM mtDNA. Our data demonstrate that the mitochondrial subunits encoded by the RM mtDNA are associated with higher enzymatic activities than the gene products of the SM mtDNA. J. Exp. Zool. (Mol. Dev. Evol.) 312B:108–117, 2009. © 2008 Wiley‐Liss, Inc.
Temporal analysis of ectopic enamel production in incisors from sprouty mutant mice
Authors: Boran Tomas , Peterkova Renata , Lesot Herve , Lyons David B. , Peterka Miroslav , Klein Ophir D. 
Published: December 2008

AbstractThe mouse incisor has two unusual features: it grows continuously and it is covered by enamel exclusively on the labial side. The continuous growth is driven in part by epithelial stem cells in the cervical loop region that can both self‐renew and give rise to ameloblasts. We have previously reported that ectopic enamel is found on the lingual side of the incisor in mice with loss‐of‐function of sprouty (spry) genes. Spry2+/−; Spry4−/− mice, in which three sprouty alleles have been inactivated, have ectopic enamel as a result of upregulation of epithelial‐mesenchymal FGF signaling in the lingual part of the cervical loop. Interestingly, lingual enamel is also present in the early postnatal period in Spry4−/− mice, in which only two sprouty alleles have been inactivated, but ectopic enamel is not found in adults of this genotype. To explore the mechanisms underlying the disappearance of lingual enamel in Spry4−/− adults, we studied the fate of the lingual enamel in Spry4−/− mice by comparing the morphology and growth of their lower incisors with wild type and Spry2+/−; Spry4−/− mice at several timepoints between the perinatal period and adulthood. Ameloblasts and enamel were detected on the lingual side in postnatal Spry2+/−; Spry4+/− incisors. By contrast, new ectopic ameloblasts ceased to differentiate after postnatal day 3 in Spry4−/− incisors, which was followed by a progressive loss of lingual enamel. Both the posterior extent of lingual enamel and the time of its last deposition were variable early postnatally in Spry4−/− incisors, but in all Spry4−/− adult incisors the lingual enamel was ultimately lost through continuous growth and abrasion of the incisor. J. Exp. Zool. (Mol. Dev. Evol.) 312B:473–485, 2009. © 2009 Wiley‐Liss, Inc.
Vibrational spectra and potential energy distributions for 1‐benzyl‐1H‐imidazole by normal coordinate analysis
Authors: James C. , Ravikumar C. , Jayakumar V. S. , Hubert Joe I. 
Published: December 2008

AbstractThe Fourier‐transform (FT) Raman and infrared (IR) spectra of the crystallized novel pharmaceutical molecule 1‐benzyl‐1H‐imidazole (BI) were recorded and analyzed. The geometry, intermolecular hydrogen bond, and harmonic vibrational wavenumbers of BI were investigated with the help of B3PW91 density functional theory (DFT) methods. The detailed interpretation of the vibrational spectra was carried out with the aid of normal coordinate analysis (NCA) following the scaled quantum mechanical force field methodology (SQMFF). The aromaticities of the imidazole and phenyl rings were studied using the standard harmonic oscillator model of aromaticity (HOMA) index. Natural bond orbital (NBO) analysis on BI was carried out to demonstrate the various intramolecular interactions that are responsible for the stabilization of this molecule leading to its medicinal activity. The potential energy profile corresponding to the torsion around the bridge bonds connecting the two rings was drawn to explain the steric and/or electronic effects using potential energy surface (PES) scan studies. The pronounced double‐bond localization in the imidazole ring upon intermolecular H‐bonding appears to be the cause for its enhanced aromaticity. Copyright © 2008 John Wiley & Sons, Ltd.
Quantitative capillary electrophoresis and its application in analysis of alkaloids in tea, coffee, coca cola, and theophylline tablets
Authors: Li Mengjia , Zhou Junyi , Gu Xue , Wang Yan , Huang Xiaojing , Yan Chao 
Published: December 2008

AbstractA quantitative CE (qCE) system with high precision has been developed, in which a 4‐port nano‐valve was isolated from the electric field and served as sample injector. The accurate amount of sample was introduced into the CE system with high reproducibility. Based on this system, consecutive injections and separations were performed without voltage interruption. Reproducibilities in terms of RSD lower than 0.8% for retention time and 1.7% for peak area were achieved. The effectiveness of the system was demonstrated by the quantitative analysis of caffeine, theobromine, and theophylline in real samples, such as tea leaf, roasted coffee, coca cola, and theophylline tablets.
Fast Synthesis of Nanostructured Microspheres of a Bridged Silsesquioxane via Ultrasound‐Assisted Sol–Gel Processing
Authors: Romeo Hernán E. , Fanovich María A. , Williams Roberto J. J. , Matějka Libor , Pleštil Josef , Brus Jiří 
Published: December 2008

AbstractMicrospheres of a nanostructured bridged silsesquioxane were synthesized by employing ultrasound‐assisted self‐assembly of a bridged monomer via sol–gel processing. The bridged precursor was synthesized from glycidoxypropyl(trimethoxysilane) (GPMS) (2 mol) and cyclohexylamine (1 mol). The main factor controlling the generation of a stable dispersion of microspheres was the time at which the phase separation of the silsesquioxane was produced during the hydrolytic condensation. An appropriate blend of THF/n‐hexane as a solvent enabled to rapidly generate a stable dispersion exhibiting a low polydispersity. The mild reaction conditions produced the nanostructuring of the silsesquioxane characterized by a fine structure in SAXS spectrum. Inorganic domains were arranged in a two‐dimensional hexagonal system leading to the formation of cavities in the microspheres which could be employed as host–guest systems in advanced technologies.magnified image
Rasch analysis of the hospital anxiety and depression scale in Parkinson's disease
Authors: Forjaz Maria João , Rodriguez‐Blázquez Carmen , Martinez‐Martin Pablo ,   on behalf of the Longitudinal Parkinson's Disease Patient Study (Estudio Longitudinal de Pacientes con Enfermedad de Parkinson—ELEP) Group
Published: December 2008

AbstractThe hospital anxiety and depression scale (HADS) is commonly used to assess mood in Parkinson's disease (PD) patients. Very few studies analyze the scale from the standpoint of item response theory. This article sought to analyze how the HADS fits the Rasch model in PD. The HADS was administered to 387 PD patients. Three sets of Rasch analyses were performed for the HADS total score, and anxiety and depression subscales (HADS‐T, ‐A, and ‐D, respectively). Although the HADS‐T and HADS‐A displayed a good fit, with little threshold disordering and no differential item functioning, the HADS‐D failed to fit the model. The person separation index, a reliability measure, was 0.87 (HADS‐T) and 0.80 (HADS‐A). Both HADS‐T and HADS‐A showed unidimensionality. Our results supported the use of HADS‐T as a measure of psychological distress in PD patients. Moreover, the HADS‐A was also an adequate anxiety measure. Further research is required to address the use of HADS‐D in PD. © 2008 Movement Disorder Society
Resurfacing of a complex upper extremity injury: An excellent indication for the dorsal thoracic fascial flap
Authors: Hazani Ron , Brooks Darrell , Buntic Rudolf F. 
Published: December 2008

AbstractWe report a case of a 24‐year‐old patient who sustained a mutilating crush injury to the left forearm. After thorough debridement and stabilization of the skeletal injury, the dorsal thoracic fascial flap was used to resurface the circumferential wound, protect the underlying structures, and provide a gliding surface for the exposed tendons. The flap was safely transected during revision surgery, and at 6‐months follow‐up, excellent functional and cosmetic results were achieved. The dorsal thoracic fascia is a thin, durable, and pliable tissue that is based on a long vascular pedicle. We consider the dorsal thoracic fascial flap as a valuable option for coverage of complex upper extremity injuries and highly recommend its use. © 2008 Wiley‐Liss, Inc. Microsurgery, 2009.
Whole‐body imaging at 7T: Preliminary results
Authors: Vaughan J. Thomas , Snyder Carl J. , DelaBarre Lance J. , Bolan Patrick J. , Tian Jinfeng , Bolinger Lizann , Adriany Gregor , Andersen Peter , Strupp John , Ugurbil Kamil 
Published: December 2008

AbstractThe objective of this study was to investigate the feasibility of whole‐body imaging at 7T. To achieve this objective, new technology and methods were developed. Radio frequency (RF) field distribution and specific absorption rate (SAR) were first explored through numerical modeling. A body coil was then designed and built. Multichannel transmit and receive coils were also developed and implemented. With this new technology in hand, an imaging survey of the “landscape” of the human body at 7T was conducted. Cardiac imaging at 7T appeared to be possible. The potential for breast imaging and spectroscopy was demonstrated. Preliminary results of the first human body imaging at 7T suggest both promise and directions for further development. Magn Reson Med 61:244–248, 2009. © 2008 Wiley‐Liss, Inc.
Implementation of three‐dimensional wavelet encoding spectroscopic imaging: In vivo application and method comparison
Authors: Young Richard , Serrai Hacene 
Published: December 2008

AbstractWe have recently proposed a two‐dimensional Wavelet Encoding‐Spectroscopic Imaging (WE‐SI) technique as an alternative to Chemical Shift Imaging (CSI), to reduce acquisition time and crossvoxel contamination in magnetic resonance spectroscopic imaging (MRSI). In this article we describe the extension of the WE‐SI technique to three dimensions and its implementation on a clinical 1.5 T General Electric (GE) scanner. Phantom and in vivo studies are carried out to demonstrate the usefulness of this technique for further acquisition time reduction with low voxel contamination. In wavelet encoding, a set of dilated and translated prototype functions called wavelets are used to span a localized space by dividing it into a set of subspaces with predetermined sizes and locations. In spectroscopic imaging, this process is achieved using radiofrequency (RF) pulses with profiles resembling the wavelet shapes. Slice selective excitation and refocusing RF pulses, with single‐band and dual‐band profiles similar to Haar wavelets, are used in a modified PRESS sequence to acquire 3D WE‐SI data. Wavelet dilation and translation are achieved by changing the strength of the localization gradients and frequency shift of the RF pulses, respectively. The desired spatial resolution in each direction sets the corresponding number of dilations (increases in the localization gradients), and consequently, the number of translations (frequency shift) of the Haar wavelets (RF pulses), which are used to collect magnetic resonance (MR) signals from the corresponding subspaces. Data acquisition time is reduced by using the minimum recovery time (TRmin), also called effective time, when successive MR signals from adjacent subspaces are collected. Inverse wavelet transform is performed on the acquired data to produce metabolite maps. The proposed WE‐SI method is compared in terms of acquisition time, pixel bleed, and signal‐to‐noise ratio to the CSI technique. The study outcome shows that 3D WE‐SI provides accurate results while reducing both acquisition time and voxel contamination. Magn Reson Med 61:6–15, 2009. © 2008 Wiley‐Liss, Inc.
Mechanical model of neural tissue displacement during Lorentz effect imaging
Authors: Roth Bradley J. , Basser Peter J. 
Published: December 2008

AbstractAllen Song and coworkers recently proposed a method for MRI detection of biocurrents in nerves called “Lorentz effect imaging.” When exposed to a magnetic field, neural currents are subjected to a Lorentz force that moves the nerve. If the displacement is large enough, an artifact is predicted in the MR signal. In this work, the displacement of a nerve of radius a in a surrounding tissue of radius b and shear modulus μ is analyzed. The nerve carries a current density J and lies in a magnetic field B. The solution to the resulting elasticity problem indicates that the nerve moves a distance
$BJ/4|gm$a2ln($b/a$). Using realistic parameters for a human median nerve in a 4T field, this calculated displacement is 0.013 μm or less. The distribution of displacement is widespread throughout the tissue, and is not localized near the nerve. This displacement is orders of magnitude too small to be detected by conventional MRI methods. Magn Reson Med 61:59–64, 2009. © 2008 Wiley‐Liss, Inc.
Influence of RF spoiling on the stability and accuracy of T1 mapping based on spoiled FLASH with varying flip angles
Authors: Preibisch C. , Deichmann R. 
Published: December 2008

AbstractThere is increasing interest in quantitative T1 mapping techniques for a variety of applications. Several methods for T1 quantification have been described. The acquisition of two spoiled gradient‐echo data sets with different flip angles allows for the calculation of T1 maps with a high spatial resolution and a relatively short experimental duration. However, the method requires complete spoiling of transverse magnetization. To achieve this goal, RF spoiling has to be applied. In this work it is investigated whether common RF spoiling techniques are sufficiently effective to allow for accurate T1 quantification. It is shown that for most phase increments the apparent T1 can deviate considerably from the true value. Correct results may be achieved with phase increments of 118.2° or 121.8°. However, for these values the method suffers from instabilities. In contrast, stable results are obtained with a phase increment of 50°. An algorithm is presented that allows for the calculation of corrected T1 maps from the apparent values. The method is tested both in phantom experiments and in vivo by acquiring whole‐brain T1 maps of the human brain. Magn Reson Med 61:125–135, 2009. © 2008 Wiley‐Liss, Inc.
Efficient multiple acquisitions by skipped phase encoding and edge deghosting (SPEED) using shared spatial information
Authors: Chang Zheng , Xiang Qing‐San , Ji Jim , Yin Fang‐Fang 
Published: December 2008

AbstractThe fast MRI method of Skipped Phase Encoding and Edge Deghosting (SPEED) is further developed to accelerate multiple acquisitions. In a single acquisition, SPEED first acquires three sparse ghosted edge maps with an undersampling factor of N/3, which are modeled with a double‐layer structure and described by three equations with two unknown ghosts, each with a unique ghost order index. By minimizing least‐square‐error, a pair of ghost order indexes is determined. Based on them, the two corresponding ghosts are resolved, leading to a deghosted image. In this case, three equations are needed to determine the ghost order index, while only two equations are required to resolve the two ghosts. This shows both inefficiency and potential. Multiple acquisitions often contain similar spatial information. The similarities can be used to improve efficiency by sharing the ghost order index among different acquisitions, leading to acceleration factors greater than that achievable with single acquisition. Magn Reson Med 61:229–233, 2009. © 2008 Wiley‐Liss, Inc.