bluuebunny/crossref_metadata_2025_split huggingface dataset:
Upregulation of the stress‐associated gene p8 in mouse models of demyelination and in multiple sclerosis tissues
Authors: Plant Sheila R. , Wang Ying , Vasseur Sophie , Thrash J. Cameron , Mcmahon Eileen J. , Bergstralh Daniel T. , Arnett Heather A. , Miller Stephen D. , Carson Monica J. , Iovanna Juan L. , Ting Jenny P‐Y. 
Published: December 2005

AbstractCuprizone‐induced demyelination is a mouse model of multiple sclerosis (MS) as cuprizone‐fed mice exhibit neuroinflammation and demyelination in the brain. Upon removal of cuprizone from the diet, inflammation is resolved and reparative remyelination occurs. In an Affymetrix GeneChip analysis, the stress‐associated gene p8 was strongly upregulated (>10×) during cuprizone‐induced demyelination but not remyelination. We verified this upregulation (>15×) of p8 in the CNS during demyelination by real‐time polymerase chain reaction (PCR). This upregulation is brain‐specific, as p8 is not elevated in the liver, lung, kidney, spleen, and heart of cuprizone‐treated mice. We also localized the cellular source of p8 during cuprizone treatment, and further found elevated expression during embryogenesis but not in normal adult brain. Compared with wild‐type controls, the death of oligodendrocytes in p8−/− mice is delayed, as is microglial recruitment to areas of demyelination. The corpus callosum of p8−/− mice demyelinates at a slower rate than wild‐type mice, suggesting that p8 exacerbates CNS inflammation and demyelination. Enhanced expression of p8 is also observed in the spinal cords of mice with acute experimental autoimmune encephalomyelitis (EAE) induced by PLP139‐151 peptide (10×). Increased expression is detected during disease onset and expression wanes during the remission phase. Finally, p8 is found upregulated (8×) in post‐mortem tissue from MS patients and is higher in the plaque tissue compared with adjacent normal‐appearing white and gray matter. Thus, p8 is an excellent candidate as a novel biomarker of demyelination. © 2005 Wiley‐Liss, Inc.
Non‐PKC DAG/Phorbol‐Ester receptor(s) inhibit complement receptor‐3 and nPKC inhibit scavenger receptor‐AI/II‐mediated myelin phagocytosis but cPKC, PI3k, and PLCγ activate myelin phagocytosis by both
Authors: Cohen Goni , Makranz Chen , Spira Maya , Kodama Tatsuhiko , Reichert Fanny , Rotshenker Shlomo 
Published: December 2005

AbstractComplement‐receptor‐3 (CR3/MAC‐1), scavenger‐receptor‐AI/II (SRAI/II), and Fcγ‐receptor (FcγR) can mediate myelin phagocytosis in macrophages and microglia. Paradoxically, after injury to CNS axons these receptors are expressed but myelin is not phagocytosed, suggesting that phagocytosis is subject to regulation between efficient and inefficient states. In the present work, we focus on CR3/MAC‐1 and SRAI/II‐mediated myelin phagocytosis. Phagocytosis by CR3/MAC‐1 and SRAI/II was inhibited by cPKC inhibitor Go‐6976, general‐PKC inhibitors Ro‐318220 and calphostin‐C, and BAPTA/AM, which chelates intracellular Ca2+ required for cPKC activation. Signaling/activation by cPKC are thus suggested. PMA, which mimics diacylglycerol (DAG) as an activator of cPKC, novel‐PKC (nPKC), and non‐PKC DAG‐driven molecule(s), produced a dose‐dependent dual effect on phagocytosis by CR3/MAC‐1 and SRAI/II, i.e., augmentation at low concentrations and inhibition at high concentrations. Inhibition of phagocytosis by CR3/MAC‐1 was enhanced by combining inhibiting concentrations of PMA with PKC inhibitors Go‐6976 or Ro‐318220, suggesting inhibition by PMA/DAG‐driven non‐PKC molecule(s). In contrast, inhibition of phagocytosis by SRAI/II was enhanced by combining inhibiting concentrations of PMA with cPKC inhibitor Go‐6976 but not with general‐PKC inhibitor Ro‐318220, suggesting inhibition by nPKC. Phagocytosis by CR3/MAC‐1 and SRAI/II was further inhibited by PI3K inhibitors wortmannin and LY‐294002 and PLCγ inhibitor U‐73122. Altogether, our observations suggest that CR3/MAC‐1 and SRAI/II‐mediated myelin phagocytosis share activation by PI3K, PLCγ and cPKC. The two differ, however, in that non‐PKC DAG‐driven molecule(s) inhibit CR3/MAC‐1‐mediated phagocytosis, whereas nPKC inhibit SRAI/II‐mediated phagocytosis. Each of these signaling steps may be targeted for regulating CR3/MAC‐1 and/or SRAI/II‐mediated phagocytosis between efficient and inefficient states. © 2005 Wiley‐Liss, Inc.
Selectively increased expression of the astrocytic/endothelial glucose transporter protein GLUT1 in acute liver failure
Authors: Bélanger Mireille , Desjardins Paul , Chatauret Nicolas , Butterworth Roger F. 
Published: December 2005

AbstractAcute liver failure (ALF) is consistently accompanied by alterations in brain energy metabolites and recent nuclear magnetic resonance (NMR) studies suggest disturbances in brain oxidative metabolism in experimental ALF. Glucose transport across the blood‐brain barrier is essential to sustain brain energy metabolism and is accomplished by the facilitative glucose transporter GLUT1. To investigate alterations in brain glucose uptake in acute liver failure further, GLUT1 expression and [14C]‐2‐deoxy‐D‐glucose uptake were measured in the brains of rats with hepatic devascularization. RT‐PCR and Western blot analyses showed significant increases in steady‐state levels of GLUT1 mRNA and protein in frontal cortex as early as 6 h following hepatic devascularization, (prior to the onset of brain edema and encephalopathy) which remained elevated at coma stages of encephalopathy. Expression of the astrocytic (45‐kDa) and endothelial (55‐kDa) forms of GLUT1 was increased as a result of hepatic devascularization. Exposure of cultured astrocytes to pathophysiologically relevant concentrations of ammonia resulted in increased GLUT1 expression, suggesting that elevated ammonia levels are responsible for GLUT1 upregulation in ALF. Increased GLUT1 expression in ALF was selective, since expression of the neuronal glucose transporter GLUT3 and other glucose‐regulated proteins (GRP‐78 and GRP‐94) was unaltered. [14C]‐2‐deoxy‐D‐glucose autoradiography revealed increases in cerebral glucose uptake following the induction of GLUT1 in ALF. These results suggest that ammonia‐induced increases of GLUT1 expression resulting in increased cerebral glucose uptake occur in ALF and could contribute to the pathophysiological mechanisms responsible for the neurological complications of this condition. © 2005 Wiley‐Liss, Inc.
Synthesis of multi‐labeled [14C]Aripiprazole
Authors: Bonacorsi Samuel J. , Waller Stephen C. , Kent Rinehart J. 
Published: December 2005

AbstractDevelopment of Aripiprazole as an oral treatment of schizophrenia required the synthesis of a suitably labeled drug product for use in human metabolism and pharmacokinetic studies. Due to the potential metabolic degradation of the molecule, a multi‐labeled approach utilizing 14C was adopted. The synthesis of [14C]Aripiprazole was accomplished in separate syntheses from 2,3‐dichloro[U‐14C]aniline and [3‐14C]‐cinnamic acid, respectively. Labeled versions were combined on the basis of molar radioactivity giving a final product with a radiochemical purity of 99.9% and a specific activity of 15.5 µCi/mg. Copyright © 2005 John Wiley & Sons, Ltd.
The no‐carrier‐added synthesis of bromine‐76 labeled alkenyl and alkynyl bromides using organotrifluoroborates
Authors: Kabalka George W. , Mereddy Arjun R. , Green James F. 
Published: December 2005

AbstractA straightforward radiobromination procedure has been developed for the construction of radiobrominated alkenyl and alkynyl bromides. The organotrifluoroborates used as the reactive intermediates are unique in that they are quite polar and thus readily separated from the desired products. Copyright © 2005 John Wiley & Sons, Ltd.
Syntheses and radiofluorination of two derivatives of 5‐cyano‐indole as selective ligands for the dopamine subtype‐4 receptor
Authors: Tietze Rainer , Hocke Carsten , Löber Stefan , Hübner Harald , Kuwert Torsten , Gmeiner Peter , Prante Olaf 
Published: December 2005

AbstractTwo fluoroethoxy substituted derivatives, namely 2‐[4‐(2‐(2‐fluoroethoxy)phenyl)‐piperazin‐1‐ylmethyl]indole‐5‐carbonitrile (5a) and 2‐[4‐(4‐(2‐fluoroethoxy)‐phenyl)piperazin‐1‐ylmethyl]indole‐5‐carbonitrile (5b) were synthesized as analogs of the selective D4receptor ligand 2‐[4‐(4‐fluorophenyl)piperazin‐1‐ylmethyl]indole‐5‐carbonitrile (FAUC 316).In vitrocharacterization using CHO‐cells expressing different dopamine receptor subtypes gaveKivalues of 2.1 (5a) and 9.9 nM (5b) for the dopamine D4subtype and displayed a 420‐fold D4‐selectivity over D2receptors for5b. The para‐fluoroethoxy substituted candidate5brevealed substantially reducedα1and serotoninergic binding affinities in comparison to the ortho‐fluoroethoxy substituted compound. In order to provide potential positron emission tomography (PET) imaging probes for the dopamine D4receptor,18F‐labelling conditions using [18F]fluoroethyl tosylate were optimized and led to radiochemical yields of 81 ± 5% ([18F]5a) and 47 ± 4% ([18F]5b) (n= 3, decay‐corrected and referred to labelling agent), respectively. Thus,18F‐fluoroethylation favourably at the para position of the phenylpiperazine moiety of the 5‐cyano‐indole framework proved to be tolerated by D4receptors and could also be applied to alternative scaffolds in order to develop D4radioligand candidates for PET with improved D4receptor affinity and selectivity. Copyright © 2005 John Wiley & Sons, Ltd.
Homogenous Synthesis of Hydroxyethylcellulose in NaOH/Urea Aqueous Solution
Authors: Zhou Jinping , Qin Ye , Liu Shilin , Zhang Lina 
Published: December 2005

AbstractSummary: Hydroxyethylcellulose (HEC) was synthesized by a fully homogenous method from cellulose in 7.5 wt.‐% NaOH/11 wt.‐% urea aqueous solutions under mild conditions. HEC samples were characterized with NMR, SEC‐LLS, solubility, and viscosity measurements. The MS and DS values of the obtained HEC samples are in the range from 0.54 to 1.44 and 0.45 to 1.14, respectively, and the relative DS values at C‐2 and C‐6 hydroxyl groups are slightly higher than those at C‐3 hydroxyl groups. HEC samples are soluble in water starting from a MS of 0.57 and DS of 0.49, which display high viscosity in aqueous solutions. Moreover, a NaOH/urea aqueous solution is a stable system for cellulose etherification. In this way, we could provide a simple, pollution‐free, and homogeneous aqueous solution system for synthesizing cellulose ethers.13C NMR spectra of acetylated HEC (a) in CDCl3 at 40 °C and (b) in DMSO‐d6 at 100 °C.magnified image13C NMR spectra of acetylated HEC (a) in CDCl3 at 40 °C and (b) in DMSO‐d6 at 100 °C.
Preparation and Characterization of Novel Bone Scaffolds Based on Electrospun Polycaprolactone Fibers Filled with Nanoparticles
Authors: Wutticharoenmongkol Patcharaporn , Sanchavanakit Neeracha , Pavasant Prasit , Supaphol Pitt 
Published: December 2005

AbstractSummary: Novel bone‐scaffolding materials were successfully fabricated by electrospinning from polycaprolactone (PCL) solutions containing nanoparticles of calcium carbonate (CaCO3) or hydroxyapatite (HA). The diameters of the as‐spun fibers were found to increase with the addition and increasing amounts of the nanoparticles. The observed increase in the diameters of the as‐spun fibers with the addition and increasing amounts of the nanoparticulate fillers was responsible for the observed increase in the tensile strength of the obtained fiber mats. An increase in the concentration of the base PCL solution caused the average diameter of the as‐spun PCL/HA composite fibers to increase. Increasing applied electrical potential also resulted in an increase in the diameters of the obtained PCL/HA composite fibers. Lastly, indirect cytotoxicity evaluation of the electrospun mats of PCL, PCL/CaCO3, and PCL/HA fibers based on human osteoblasts (SaOS2) and mouse fibroblasts (L929) revealed that these as‐spun mats posed no threat to the cells, a result that implied their potential for utilization as bone‐scaffolding materials.
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Materials for Peripheral Nerve Regeneration
Authors: Ciardelli Gianluca , Chiono Valeria 
Published: December 2005

AbstractSummary: Recent efforts in scientific research in the field of peripheral nerve regeneration have been directed towards the development of artificial nerve guides. We have studied various materials with the aim of obtaining a biocompatible and biodegradable two layer guide for nerve repair. The candidate materials for use as an external layer for the nerve guides were poly(caprolactone) (PCL), a biosynthetic blend between PCL and chitosan (CS) and a synthesised poly(ester‐urethane) (PU). Blending PCL, which is a biocompatible synthetic polymer, with a natural polymer enhanced the system biocompatibility and biomimetics, fastened the degradation rates and reduced the production costs. Various novel block poly(ester‐urethane)s are being synthesised by our group with tailored properties for specific tissue engineering applications. One of these poly(ester‐urethane)s, based on a low molecular weight poly(caprolactone) as the macrodiol, cycloesandimethanol as the chain extender and hexamethylene diisocyanate as the chain linker, was investigated for the production of melt extruded nerve guides. We studied natural polymers such as gelatin (G), poly(L‐lysine) (PL) and blends between chitosan and gelatin (CS/G) as internal coatings for nerve guides. In vitro and in vivo tests were performed on PCL guides internally coated either with G or PL to determine the differences in the quality of nerve regeneration associated with the type of adhesion protein. CS/G natural blends combined the good cell adhesion properties of the protein phase with the ability to promote nerve regeneration of the polysaccharide phase. Natural blends were crosslinked both by physical and chemical crosslinking methods. In vitro neuroblast adhesion tests were performed on CS/G film samples, PCL/CS and PU guides internally coated with G to evaluate the ability of such materials towards nerve repair.SEM image of a fractured section of a PCL melt extruded guide.magnified imageSEM image of a fractured section of a PCL melt extruded guide.
Adsorption of Biopolyester Depolymerase on Silicon Wafer and Poly[(R)‐3‐hydroxybutyric acid] Single Crystal Revealed by Real‐Time AFM
Authors: Numata Keiji , Kikkawa Yoshihiro , Tsuge Takeharu , Iwata Tadahisa , Doi Yoshiharu , Abe Hideki 
Published: December 2005

AbstractSummary: The adsorption behavior of PHB depolymerase from R. pickettii T1 on a silicon wafer and on P(3HB) single crystals has been studied by real‐time and AFM in air and a buffer solution. First, the morphology of PHB depolymerase adsorbed on a silicon wafer was characterized to show that one molecule of PHB depolymerase has dimensions of 2.2 ± 0.7 nm height and 16 ± 5 nm width. The observation of PHB depolymerase adsorbed on a P(3HB) single crystal indicated that the dimensions of enzyme on the crystalline surface in air were 1.2 ± 0.5 nm high and 28 ± 7 nm wide, while enzyme molecules with dimensions of 2.1 ± 0.6 nm height and 16 ± 7 nm width were detected in a buffer solution. Comparison of the dimensions of PHB depolymerase in air with those in a buffer solution showed that the enzyme was squashed in air, but not in a buffer solution. In addition, the influence of enzymatic adsorption on the molecular state of the P(3HB) crystalline surface was investigated. The AFM images of P(3HB) single crystals after enzymatic adsorption and washing with ethanol indicated that the adhesion of PHB depolymerase changed the molecular state and generated holes on the crystalline surface.Illustration and AFM images of the adsorption process of PHB depolymerase on PHB single crystals.magnified imageIllustration and AFM images of the adsorption process of PHB depolymerase on PHB single crystals.
Preparation of Nano‐Structured Polyaniline Composite Film via “Carbon Nanotubes Seeding” Approach and its Gas‐Response Studies
Authors: Ma Xingfa , Zhang Xiaobin , Li Yu , Li Guang , Wang Mang , Chen Hongzheng , Mi Yuhong 
Published: December 2005

AbstractSummary: Polyaniline composite film with nano‐structure was prepared through a chemical oxidation method by adding carbon nanotubes (CNTs) as nano‐fiber seeds. Spin‐coating or casting method was employed on the interdigital electrodes of carbon and the composite film was formed with an in‐situ polymerization approach. The gas‐response to trimethylamine was also examined at room temperature. It was found that the difference was not only in the morphology, but also in the value of gas‐sensitivity. Comparing with films without the CNTs, the value of gas‐sensitivity decreased dramatically, while the baseline current of the sensor increased remarkably. This method can be an effective way to adjust the gas‐sensitivity of sensors made from polyaniline composite film by adding a small amount of carbon nanotube. XRD data showed that the degree of orientation of polyaniline was increased greatly with the addition of CNTs.Morphology and reproducibility (inset) of polyaniline composite film containing carbon nanotubes.magnified imageMorphology and reproducibility (inset) of polyaniline composite film containing carbon nanotubes.
Mechanical and Thermal Properties of Flexible Poly(propylene) Composites
Authors: Houshyar Shadi , Shanks Robert A. 
Published: December 2005

AbstractSummary: The melting temperature difference between poly(propylene) (PP) fibre and random poly(propylene‐co‐ethylene) (PPE) was exploited to establish processing conditions for all‐PP composite. Under these conditions, the matrix must be liquid to ensure good wetting and impregnation of fibres, though temperatures must be low enough to avoid melting of fibres. The high chemical compatibility of the two components allowed creation of strong physico‐chemical interactions, favouring strong interfacial adhesion. Static and dynamic mechanical properties and morphology of all‐PP composites were investigated according to method of preparation and compared with the behaviour of hot compacted composites, prepared under different moulding conditions. The composites were compacted with varying pressure and time, and mechanical and thermal properties of the resulting sheets were measured. With increased moulding time, more fibres melted or their original properties deteriorated. Fast cooling or quenching caused imperfect morphology. Moulding pressure played an important role. Morphology of the optimum hot compacted composite was investigated using scanning electron microscopy before and after tensile testing. Tensile fracture surfaces showed a melted phase epitaxially crystallised onto the remaining orientated phase. Compacted composites showed fibre shapes under a thin layer of PPE with all of the gaps between fibres filled by melted PPE matrix.SEM of compacted all‐PP composite without quenching.magnified imageSEM of compacted all‐PP composite without quenching.
Multipass membrane protein structure prediction using Rosetta
Authors: Yarov‐Yarovoy Vladimir , Schonbrun Jack , Baker David 
Published: December 2005

AbstractWe describe the adaptation of the Rosetta de novo structure prediction method for prediction of helical transmembrane protein structures. The membrane environment is modeled by embedding the protein chain into a model membrane represented by parallel planes defining hydrophobic, interface, and polar membrane layers for each energy evaluation. The optimal embedding is determined by maximizing the exposure of surface hydrophobic residues within the membrane and minimizing hydrophobic exposure outside of the membrane. Protein conformations are built up using the Rosetta fragment assembly method and evaluated using a new membrane‐specific version of the Rosetta low‐resolution energy function in which residue–residue and residue–environment interactions are functions of the membrane layer in addition to amino acid identity, distance, and density. We find that lower energy and more native‐like structures are achieved by sequential addition of helices to a growing chain, which may mimic some aspects of helical protein biogenesis after translocation, rather than folding the whole chain simultaneously as in the Rosetta soluble protein prediction method. In tests on 12 membrane proteins for which the structure is known, between 51 and 145 residues were predicted with root‐mean‐square deviation <4 Å from the native structure. Proteins 2006. © 2005 Wiley‐Liss, Inc.
Pressure perturbation calorimetry of helical peptides
Authors: Barrett Devin G. , Minder C. Michael , Mian Michelle U. , Whittington Shelly J. , Cooper W. John , Fuchs Kristin M. , Tripathy Ashutosh , Waters Marcey L. , Creamer Trevor P. , Pielak Gary J. 
Published: December 2005

AbstractPressure perturbation calorimetry quantifies the temperature dependence of a solute's thermal expansion coefficient, providing information about solute–solvent interactions. We tested the idea that pressure perturbation calorimetry can provide information about solvent‐accessible surface area by studying peptides with different secondary structures. The peptides comprised two host–guest series: one predominately an α‐helix, the other predominately a polyproline II helix. In aqueous buffer, we find a correlation between the amount of secondary structure as assessed by circular dichroism spectropolarimetry and the pressure perturbation calorimetry data. We conclude that pressure perturbation calorimetry can provide information about the exposure of polar and nonpolar surface area. Data acquired in a buffered urea solution, however, are not as easily interpreted. Proteins 2006. © 2005 Wiley‐Liss, Inc.
A topology‐constrained distance network algorithm for protein structure determination from NOESY data
Authors: Huang Yuanpeng Janet , Tejero Roberto , Powers Robert , Montelione Gaetano T. 
Published: December 2005

AbstractThis article formulates the multidimensional nuclear Overhauser effect spectroscopy (NOESY) interpretation problem using graph theory and presents a novel, bottom‐up, topology‐constrained distance network analysis algorithm for NOESY cross peak interpretation using assigned resonances. AutoStructure is a software suite that implements this topology‐constrained distance network analysis algorithm and iteratively generates structures using the three‐dimensional (3D) protein structure calculation programs XPLOR/CNS or DYANA. The minimum input for AutoStructure includes the amino acid sequence, a list of resonance assignments, and lists of 2D, 3D, and/or 4D‐NOESY cross peaks. AutoStructure can also analyze homodimeric proteins when X‐filtered NOESY experiments are available. The quality of input data and final 3D structures is evaluated using recall, precision, and F‐measure (RPF) scores, a statistical measure of goodness of fit with the input data. AutoStructure has been tested on three protein NMR data sets for which high‐quality structures have previously been solved by an expert, and yields comparable high‐quality distance constraint lists and 3D protein structures in hours. We also compare several protein structures determined using AutoStructure with corresponding homologous proteins determined with other independent methods. The program has been used in more than two dozen protein structure determinations, several of which have already been published. Proteins 2006. © 2005 Wiley‐Liss, Inc.