bluuebunny/crossref_metadata_2025_split huggingface dataset:
Elastic fiber formation: A dynamic view of extracellular matrix assembly using timer reporters
Authors: Kozel Beth A. , Rongish Brenda J. , Czirok Andras , Zach Julia , Little Charles D. , Davis Elaine C. , Knutsen Russell H. , Wagenseil Jessica E. , Levy Marilyn A. , Mecham Robert P. 
Published: October 2005

AbstractTo study the dynamics of elastic fiber assembly, mammalian cells were transfected with a cDNA construct encoding bovine tropoelastin in frame with the Timer reporter. Timer is a derivative of the DsRed fluorescent protein that changes from green to red over time and, hence, can be used to distinguish new from old elastin. Using dynamic imaging microscopy, we found that the first step in elastic fiber formation is the appearance of small cell surface‐associated elastin globules that increased in size with time (microassembly). The elastin globules are eventually transferred to pre‐existing elastic fibers in the extracellular matrix where they coalesce into larger structures (macroassembly). Mechanical forces associated with cell movement help shape the forming, extracellular elastic fiber network. Time‐lapse imaging combined with the use of Timer constructs provides unique tools for studying the temporal and spatial aspects of extracellular matrix formation by live cells. J. Cell. Physiol. 207: 87–96, 2006. © 2005 Wiley‐Liss, Inc.
Transverse relaxation effect of MRI contrast agents: A crucial issue for quantitative measurements of cerebral perfusion
Authors: Kiselev Valerij G. 
Published: October 2005

AbstractQuantitative cerebral perfusion imaging using dynamic susceptibility contrast (DSC) MRI requires the dynamic measurement of changes in contrast agent concentration in cerebral tissue and its feeding artery. In this work the tracer kinetics approach to general tracer‐based perfusion imaging is reviewed. In the typical practical setting, measurements of change in transverse relaxation (ΔR2) derived from MR signals are assumed to be substitutes for true concentration measurements. The implications and limitations of this assumption are reviewed in the light of various results obtained in theoretical, simulated, and experimental studies. The mechanisms of R2 changes in biological media are discussed. These mechanisms operate over different spatial scales and differentially influence gradient‐echo (GE) and spin‐echo (SE) MRI signals. This differential sensitivity can be used to assess vessel size in the microvasculature. Finally, the need for well controlled experimental data to provide input parameters and/or experimental tests of theoretical models is emphasized. J. Magn. Reson. Imaging 2005. © 2005 Wiley‐Liss, Inc.
Bolus dispersion issues related to the quantification of perfusion MRI data
Authors: Calamante Fernando 
Published: October 2005

AbstractQuantification of cerebral blood flow (CBF) using dynamic‐susceptibility contrast (DSC) MRI relies on the deconvolution of the arterial input function (AIF). The AIF is commonly measured in a major artery (e.g., the middle cerebral artery), and the estimated function is used as a global AIF for the whole slice. However, the presence of bolus delay and dispersion between the artery and the tissue of interest can introduce significant errors in CBF quantification. While several methods have been introduced to minimize or eliminate the effects of bolus delay, the correction of bolus dispersion is more difficult to address because it requires a model for the vascular bed. This article summarizes how this dispersion effect can be incorporated into the model for CBF quantification, and discusses the magnitude of the errors introduced. Furthermore, alternative methods for correcting or minimizing the effects of bolus dispersion in the quantification of CBF are reviewed. J. Magn. Reson. Imaging 2005. © 2005 Wiley‐Liss, Inc.
Principles of cerebral perfusion imaging by bolus tracking
Authors: Østergaard Leif 
Published: October 2005

AbstractThe principles of cerebral perfusion imaging by the method of dynamic susceptibility contrast magnetic resonance imaging (DSC‐MRI) (bolus tracking) are described. The MRI signals underlying DSC‐MRI are discussed. Tracer kinetics procedures are defined to calculate images of cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT). Two general categories of numerical procedures are reviewed for deriving CBF from the residue function. Procedures that involve deconvolution, such as Fourier deconvolution or singular value decomposition (SVD), are classified as model‐independent methods because they do not require a model of the microvascular hemodynamics. Those methods in principle also yield a measure of the tissue impulse response function and the residue function, from which microvascular hemodynamics can be characterized. The second category of methods is the model‐dependent methods, which use models of tracer transport and retention in the microvasculature. These methods do not yield independent measures of the residue function and may introduce bias when the physiology does not follow the model. Statistical methods are sometimes used, which involve treating the residue function as a deconvolution kernel and optimizing (fitting) the kernel from the experimental data using procedures such as maximum likelihood. Finally, other hemodynamic indices that can be measured from DSC‐MRI data are described. J. Magn. Reson. Imaging 2005. © 2005 Wiley‐Liss, Inc.
Quantifying CBF with arterial spin labeling
Authors: Buxton Richard B. 
Published: October 2005

AbstractThe basic principles of measuring cerebral blood flow (CBF) using arterial spin labeling (ASL) are reviewed. The measurement is modeled by treating the ASL method as a magnetic resonance imaging (MRI) version of a microsphere study, rather than a diffusible tracer study. This approach, particularly when applied to pulsed ASL (PASL) experiments, clarifies that absolute calibration of CBF primarily depends on global properties of blood, rather than local tissue properties such as the water partition coefficient or relaxation time. However, transit delays from the tagging region to the image voxel are a potential problem in all standard ASL methods. The key to quantitative CBF measurements that compensate for this systematic error is to create a well‐defined bolus of tagged blood and to ensure that all of the bolus has been delivered to an imaging voxel at the time of measurement. Two practical technical factors considered here are 1) producing a tagged bolus with a well‐defined temporal width and 2) accounting for reduction in magnitude of the tagged magnetization due to relaxation. The ASL approach has the potential to provide a robust estimation of CBF, although the timing of water exchange into tissue and the effects of pulsatile flow require further investigation. J. Magn. Reson. Imaging 2005. © 2005 Wiley‐Liss, Inc.
Facile Surface Superhydrophilic Modification: NVP/MBA Inverse Microemulsion Surface‐Grafting Polymerization Initiated by UV Light
Authors: Wang Yongxin , Deng Jianping , Zhong Wenbin , Kong Lingbing , Yang Wantai 
Published: October 2005

AbstractSummary: Superhydrophilic modification of poly(propylene) and poly(ethylene terephthalate) films' surfaces was realized by the UV‐initiated surface photografting of a N‐vinyl pyrrolidone/N,N′‐methylenebisacrylamide inverse microemulsion. AFM characterization of the treated films' surface revealed that it was the grafted quasi‐bimodal (ca. 45 and 110 nm) particles of cross‐linked poly(N‐vinyl pyrrolidone) that led to superhydrophilicity of the surface. The grafted nanometer‐scale particles showed little influence on the transparency of the substrate's surface, but endowed long‐term stability to the superhydrophilicity.The surface morphology of the PP film grafted with a NVP/MBA inverse microemulsion via a one‐step method. Quasi‐bimodal particles (ca. 45 nm and 110 nm) were tethered on the film's surface, and the corresponding surface water CA fell below 5°.magnified imageThe surface morphology of the PP film grafted with a NVP/MBA inverse microemulsion via a one‐step method. Quasi‐bimodal particles (ca. 45 nm and 110 nm) were tethered on the film's surface, and the corresponding surface water CA fell below 5°.
Vapor‐Based Synthesis of Poly[(4‐formyl‐p‐xylylene)‐co‐(p‐xylylene)] and Its Use for Biomimetic Surface Modifications
Authors: Nandivada Himabindu , Chen Hsien‐Yeh , Lahann Joerg 
Published: October 2005

AbstractSummary: The vapor‐based synthesis and characterization of a reactive polymer, poly[(4‐formyl‐p‐xylylene)‐co‐(p‐xylylene)] (1), have been reported. The reactive polymer coating enables the immobilization of oligosaccharides via the chemoselective aldehyde‐hydrazide coupling reaction.
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Self‐Organizing Alignment of Carbon Nanotubes in Thermoplastic Polyurethane
Authors: Chen Wei , Tao Xiaoming 
Published: October 2005

AbstractSummary: A simple compounding technique for the fabrication of polymer nanocomposites with single‐walled carbon nanotubes having exceptional alignment and improved mechanical properties is described. The aligned‐nanotube composite was prepared by dissolving single‐walled carbon nanotubes in a solution of thermoplastic polyurethane and tetrahydrofuran. Solvent‐polymer interactions that induce the orientation of soft chain segments during the swelling and moisture curing stage are believed to serve as a driving force for the macroscopic alignment of the carbon nanotubes.Alignment of single‐walled carbon nanotubes in thermoplastic polyurethane during polar solvent exposure.magnified imageAlignment of single‐walled carbon nanotubes in thermoplastic polyurethane during polar solvent exposure.
Sensitivity and specificity of a self‐administered questionnaire for familial screening of adult‐onset dystonia
Authors: Aniello Maria Stella , Martino Davide , Masi Gianluca , Livrea Paolo , Defazio Giovanni 
Published: October 2005

AbstractWe developed a self‐administered questionnaire for screening the most common adult‐onset dystonias. It was tested in 90 first‐degree relatives of 22 adult‐onset dystonia patients, yielding 79% sensitivity and 94% specificity. Simulation of a case‐finding procedure based on serial application of the questionnaire and clinical examination of both subjects screening positive and subjects screening negative who had < 8 years of schooling increased sensitivity to 95% and specificity to 100%. This questionnaire may be an important screening resource for familial aggregation studies to be used in the context of a complex case‐finding procedure. © 2005 Movement Disorder Society
Dicondensed indolinobenzospiropyrans as precursors of thermo‐ and photochromic spiropyrans. Part II: assignment of 1H and 13C NMR spectra
Authors: Keum Sam‐Rok , Ahn Su‐Mi , Roh Se‐Jung , Park Su‐Jin , Kim Sung‐Hoon , Koh Kwangnak 
Published: October 2005

AbstractThe 1H and 13C NMR spectra of dicondensed indolinobenzospiropyrans as precursors of thermo‐ and photochromic spiropyrans, DC1–DC5, were completely assigned. Especially, the 1H assignment and coupling characteristics of the diastereotopic protons at the carbon‐3 position of the benzopyran rings were achieved by conducting 1H–1H COSY and nOe experiments. The dihedral angles (θ1, θ2 and θ3) calculated from the experimental values of the vicinal coupling constants (3J) of DC5 are in good agreement with the observed values in the solid state. All of the carbons in the DC dye molecules were investigated through a combination of heteronuclear 2D‐shift correlation spectroscopy (HETCOR) and DEPT135. Copyright © 2005 John Wiley & Sons, Ltd.
Carbon‐13 and proton NMR assignments of a new agathisflavone derivative
Authors: de Carvalho Mario Geraldo , do Rocha Gomes Mario Sergio , Fernandes Pereira André Hilário , de Souza Daniel Juliana Feijó , Schripsema Jan 
Published: October 2005

AbstractThe 1H and 13C NMR spectra of 5‐acetyl‐7,4′‐dimethoxyflavone‐(6–8″)‐5″‐acetyl‐7″,4‴‐dimethoxyflavone, a new agathisflavone derivative, were completely assigned on the basis of 1D and 2D NMR techniques. Copyright © 2005 John Wiley & Sons, Ltd.
Noninvasive monitoring of gene correction in dystrophic muscle
Authors: Walter Glenn , Cordier Laurence , Bloy Dorothy , Lee Sweeney H. 
Published: October 2005

AbstractGene and stem cell transfer have shown tremendous potential in rescuing dystrophic muscle in animal models. However, monitoring of gene transfer efficacy in clinical settings currently requires invasive muscle biopsies. We determined whether 1H‐magnetic resonance spectroscopy (MRS) and imaging (MRI) could be used to noninvasively monitor gene correction in dystrophic skeletal muscle. MRI/MRS measurements were performed in murine models of Limb Girdle (γsg−/−) and Duchenne muscular dystrophy (mdx). Viral delivery of γsg into γsg−/− muscles was achieved using both an adenovirus and an adenoassociated virus. T2‐weighted MRIs consistently revealed hyperintense regions in muscles of dystrophic mice, which agreed well with histologically determined damaged muscle fibers. 1H‐MRS revealed that the increase in T2 in dystrophic muscle is not due to fatty tissue infiltration. Reintroduction of the γsg gene in γsg−/− muscles restored normal muscle histology, membrane stability, and T2 contrast. Expression of γsg also significantly decreased the number of pixels with increased T2 values and MRI contrast agent uptake. Our data demonstrate that therapeutic correction of dystrophic lesions can be noninvasively monitored using endogenous MR contrast. This may be particularly relevant for future interventions in children with muscular dystrophy. Magn Reson Med, 2005. © 2005 Wiley‐Liss, Inc.
Contiguous spread of Mycobacterium ulcerans in Buruli ulcer lesions analysed by histopathology and real‐time PCR quantification of mycobacterial DNA
Authors: Rondini Simona , Horsfield Catherine , Mensah‐Quainoo Ernestina , Junghanss Thomas , Lucas Sebastian , Pluschke Gerd 
Published: October 2005

AbstractThe distribution of M. ulcerans in Buruli ulcer lesions was analysed by IS2404 real‐time PCR quantification of M. ulcerans DNA and by semi‐quantitative microscopic assessment of the number of acid‐fast bacilli (AFB). Mycobacterial burden was compared with histopathological changes. Focal distribution of tissue destruction extending into areas with high and low mycobacterial burden was a feature in all lesions analysed. Even where most of the mycobacteria were washed out of ulcerative lesions, peaks of mycobacterial DNA and AFB in the necrotic base of the ulcers still marked the position of the primary infection focus. Significant amounts of mycobacterial DNA and microcolonies were also present in samples from more peripheral regions and occasionally in excised margins of macroscopically and histologically healthy‐appearing excised tissue margins. Additional peaks of mycobacterial DNA clearly marked sites where satellite lesions were developing. Even when granulomas provided evidence for the development of cell‐mediated immunity, development of satellite lesions by contiguous spreading was not completely prevented. Areas free of mycobacterial DNA were found between primary and secondary infection foci and around scarring tissue of healing lesions. These results demonstrate that IS2404 real‐time PCR analysis is a better tool than the less sensitive and only semi‐quantitative microscopic enumeration of AFB for studying the dynamics of M. ulcerans infection in situ. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Oxidative stress in fibroblasts from patients with pseudoxanthoma elasticum: possible role in the pathogenesis of clinical manifestations
Authors: Pasquali‐Ronchetti Ivonne , Garcia‐Fernandez Maria Inmaculada , Boraldi Federica , Quaglino Daniela , Gheduzzi Dealba , De Vincenzi Paolinelli Chiara , Tiozzo Roberta , Bergamini Stefania , Ceccarelli Daniela , Muscatello Umberto 
Published: October 2005

AbstractPseudoxanthoma elasticum (PXE) is a genetic disease characterized by calcification and fragmentation of elastic fibres of the skin, cardiovascular system and eye, caused by mutations of the ABCC6 gene, which encodes the membrane transporter MRP6. The pathogenesis of the lesions is unknown. Based on studies of similar clinical and histopathological damage present in haemolytic disorders, our working hypothesis is that PXE lesions may result from chronic oxidative stress occurring in PXE cells as a consequence of MRP6 deficiency. Our results show that PXE fibroblasts suffer from mild chronic oxidative stress due to the imbalance between production and degradation of oxidant species. The findings also show that this imbalance results, at least in part, from the loss of mitochondrial membrane potential (ΔΨm) with overproduction of H2O2. Whether mitochondrial dysfunction is the main factor responsible for the oxidative stress in PXE cells remains to be elucidated. However, mild chronic generalized oxidative stress could explain the great majority of structural and biochemical alterations already reported in PXE. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Molecular pathogenesis of anemia of chronic disease
Authors: Ganz Tomas 
Published: October 2005

AbstractMost patients suffering from chronic infections, chronic inflammatory diseases, and some malignancies develop a mild to moderate anemia designated anemia of chronic disease or anemia of inflammation. Patients with this anemia have low serum iron, low to normal transferrin, and high to normal serum ferritin concentration. The anemia is caused by increased inflammatory cytokines, especially IL‐6, inducing increased production of the iron‐regulatory hormone hepcidin by hepatocytes. Hepcidin blocks the release of iron from macrophages, hepatocytes, and enterocytes, causing the characteristic hypoferremia associated with this anemia and iron‐deprivation of the developing erythrocytes. © 2005 Wiley‐Liss, Inc.
Impact of whole‐body MRI and FDG‐PET on staging and assessment of therapy response in a patient with Ewing sarcoma
Authors: Furth C. , Amthauer H. , Denecke T. , Ruf J. , Henze G. , Gutberlet M. 
Published: October 2005

AbstractIn patients with Ewing sarcoma, precise staging is not only crucial for the therapeutic regimen but also for a reliable evaluation of response to therapy. We report on a 15‐year‐old girl with metastatic spread of a Ewing sarcoma who, apart from conventional staging by bone scan, chest X‐ray and CT, was subsidiary examined by FDG‐PET and whole‐body MRI before and after chemotherapy. Both modalities detected more bone lesions than the bone scan, which led to an altered strategy for radiotherapy. Both examinations might be a great asset to stage‐adjusted therapy regimens, ultimately influencing patient outcome. Pediatr Blood Cancer 2006; 47:607–611. © 2005 Wiley‐Liss, Inc.
Ifosfamide neurotoxicity: An atypical presentation with psychiatric manifestations
Authors: Kerdudo C. , Orbach D. , Sarradet J.L. , Doz F. 
Published: October 2005

AbstractIfosfamide can be responsible for acute central neurotoxicity in children and adolescents treated for cancer. The signs of acute encephalopathy most frequently observed are: alteration of consciousness, cerebellar syndrome, asthenia, urinary incontinence, cranial nerve palsy, and seizures. Various combinations of these signs may occur, but disorders of consciousness and drowsiness are common. We describe the case of a young man presenting with reversible acute hypomanic disorder during ifosfamide‐based chemotherapy and discuss the possible mechanisms of this toxicity. © 2005 Wiley‐Liss, Inc.
Viscoelastic properties of ionic polymer composites reinforced by soy protein isolate
Authors: Jong L. 
Published: October 2005

AbstractBoth linear and nonlinear viscoelastic properties of ionic polymer composites reinforced by soy protein isolate (SPI) were studied. Viscoelastic properties were related to the aggregate structure of fillers. The aggregate structure of SPI is consisted of submicron size of globule protein particles that form an open aggregate structure. SPI and carbon black (CB) aggregates characterized by scanning electron microscope and particle size analyzer indicate that CB aggregates have a smaller primary particle and aggregate size than SPI aggregates, but the SPI composites have a slightly greater elastic modulus in the linear viscoelastic region than the CB composites. The composite containing 3–40 wt % of SPI has a transition in the shear elastic modulus between 6 and 8 vol % filler, indicating a percolation threshold. CB composites also showed a modulus transition at <6 vol %. The change of fractional free volume with filler concentration as estimated from WLF fit of frequency shift factor also supports the existence of a percolation threshold. Nonlinear viscoelastic properties of filler, matrix, and composites suggested that the filler‐immobilized rubber network generated a G′ maximum in the modulus‐strain curves and the SPI formed a stronger filler network than the CB in these composites. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3503–3518, 2005
Ionic aggregates in Zn‐ and Na‐neutralized poly(ethylene‐ran‐methacrylic acid) blown films
Authors: Benetatos Nicholas M. , Winey Karen I. 
Published: October 2005

AbstractThe morphology of ionic aggregates in semicrystalline Zn‐ and Na‐neutralized poly(ethylene‐ran‐methacrylic acid) (EMAA) ionomer blown films has been explored with scanning transmission electron microscopy (STEM) and small angle X‐ray scattering. The ionic aggregates of Zn‐EMAA are spherical, monodisperse, and uniformly distributed in as‐extruded pellets and blown films prepared at low and high blow‐up ratio. Thus, although the biaxial stresses of film blowing are sufficient to alter the PE superstructure, the ionic aggregates in Zn‐EMAA are unaffected. In contrast, the morphology of Na‐EMAA as detected by STEM changes from featureless in the as‐extruded pellets to a heterogeneous distribution of Na‐rich aggregates in the blown films. This transformation in Na‐EMAA morphology is consistent with our earlier study of quiescent annealing, suggesting that the morphological change is the result of thermal processing rather than the biaxial stresses of film blowing. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3549–3554, 2005
Morphological characterization of nylon‐6 nanocomposite following a large‐scale simple shear process
Authors: Weon J.‐I. , Xia Z.‐Y. , Sue H.‐J. 
Published: October 2005

AbstractA commercial grade nylon‐6/clay nanocomposite (from Ube industries) is subjected to a large‐scale simple shear orientation process and the resulting morphology is investigated. Both the orientation and aspect ratio of nanoclays, which can be altered by the simple shear process, are studied. The incorporation of well‐dispersed nanoclays into the nylon matrix greatly reduces the nylon chain mobility as well as the percent crystallinity. Two types of lamellar orientation have been found, as revealed by small‐angle X‐ray scattering. One type of lamellae is oriented ∼41° away from the clay surface, whereas the simple shear process induces another weakly preferred lamellar orientation nearly perpendicular to the clay surface. The formation of the above lamellar orientations appears to be related to both orientation of the clay in the nanocomposite and the simple shear process. The possible molecular mechanisms leading to the final morphology of the nylon‐6/clay nanocomposite is discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 3555–3566, 2005