bluuebunny/crossref_metadata_2025_split huggingface dataset:
The angiopoietin‐2 gene of endothelial cells is up‐regulated in hypoxia by a HIF binding site located in its first intron and by the central factors GATA‐2 and Ets‐1
Authors: Simon Marie‐Pierre , Tournaire Roselyne , Pouyssegur Jacques 
Published: August 2008

AbstractAngiopoietins are ligands of the endothelial cell tyrosine kinase receptor Tie2. Angiopoietin‐1 (Ang‐1) is widely expressed in human normal adult tissues and promotes blood vessel maturation and stabilization by inducing Tie2 receptor phosphorylation. In contrast, the antagonistic ligand Angiopoietin‐2 (Ang‐2) is up‐regulated by hypoxia, expressed only at sites of vascular remodeling and plays a crucial role in destabilizing vessels for normal or pathological angiogenesis. Ang‐2 expression is tightly regulated at transcriptional and post‐transcriptional levels. To characterize the regulatory sequences of the human Ang‐2 gene we cloned a fragment of around 8.5 kb upstream of the Ang‐2 coding sequence and analyzed the luciferase reporter activity of constructs of various lengths in endothelial and non‐endothelial cells. We isolated a minimal promoter sequence sufficient to promote significant Ang‐2 non‐cell type specific transcription. Moreover, we identified sequences conferring endothelial specificity. Indeed, sequence analysis of the fragment revealed the presence of several potential binding sites for specific endothelial regulatory factors like GATA or Ets. Using GATA‐2 and Ets‐1 co‐transfection and overexpression assay, we showed that these two factors are able to induce Ang‐2 promoter activation. We also show that hypoxic regulation of Ang‐2 is HIF‐dependent and demonstrate that HIF‐1α binds in human microvascular endothelial cells (HMVEC) to an evolutionary conserved Hypoxia‐Responsive Element (HRE) located in the first intron of the Ang‐2 gene. In conclusion, our study provides new elements in favor of HIF involvement in Ang‐2 hypoxic regulation and identifies Ets‐1 and particularly GATA‐2 as central factors in endothelial specific Ang‐2 expression. J. Cell. Physiol. 217: 809–818, 2008. © 2008 Wiley‐Liss, Inc.
DnaJB6 is present in the core of Lewy bodies and is highly up‐regulated in parkinsonian astrocytes
Authors: Durrenberger P.F. , Filiou M.D. , Moran L.B. , Michael G.J. , Novoselov S. , Cheetham M.E. , Clark P. , Pearce R.K.B. , Graeber M.B. 
Published: August 2008

AbstractDnaJ/Hsp40 chaperones determine the activity of Hsp70s by stabilizing their interaction with substrate proteins. We have predicted, based on the in silico analysis of a brain‐derived whole‐genome transcriptome data set, an increased expression of DnaJ/Hsp40 homologue, subfamily B, member 6 (DnaJB6) in Parkinson's disease (PD; Moran et al. [2006] Neurogenetics 7:1–11). We now show that DnaJB6 is a novel component of Lewy bodies (LBs) in both PD substantia nigra and PD cortex and that it is strongly up‐regulated in parkinsonian astrocytes. The presence of DnaJB6 in the center of LBs suggests an early and direct involvement of this chaperone in the neuronal disease process associated with PD. The strong concomitant expression of DnaJB6 in astrocytes emphasizes the involvement of glial cells in PD and could indicate a route for therapeutic intervention. Extracellular alpha‐synuclein originating from intravesicular alpha‐synuclein is prone to aggregation and the potential source of extracellular aggregates (Lee [2008] J. Mol. Neurosci. 34:17–22). The observed strong expression of DnaJB6 by astrocytes could reflect a protective reaction, so reducing the neuronal release of toxic alpha‐synuclein and supporting the astrocyte response in PD might limit the progression of the disease process. © 2008 Wiley‐Liss, Inc.
Effects of maternal antenatal glucocorticoid treatment on apoptosis in the ovine fetal cerebral cortex
Authors: Malaeb Shadi N. , Hovanesian Virginia , Sarasin Matthew D. , Hartmann Silvia M. , Sadowska Grazyna B. , Stonestreet Barbara S. 
Published: August 2008

AbstractWe examined the effects of single and multiple maternal glucocorticoid courses on apoptosis in the cerebral cortices of ovine fetuses (CC). Ewes received single dexamethasone or placebo courses at 104–106 or 133–135 days or multiple courses between 76–78 and 104–106 days gestation. In the single‐course groups, ewes received four 6 mg dexamethasone or placebo injections every 12 hr for 48 hr. Multiple‐course groups received the same treatment once per week for 5 weeks. Neuronal and nonneuronal apoptotic cell numbers per square millimeter were determined with TUNEL and NeuN staining and with caspase‐3 enzyme activity on CC tissues harvested at 106–108 (70%) or 135–137 (90%) days of gestation. Apoptotic cell numbers and caspase‐3 activity were 50% lower (P < 0.02) after single placebo courses at 90% than 70% gestation; 90% of apoptotic cells were (P < 0.01) nonneuronal at both ages. Nonneuronal apoptotic cells and caspase‐3 activity were 40% and 20% lower (P < 0.02) after single dexamethasone than placebo courses at 70%, but not 90%, gestation. Caspase‐3 activity was 20% lower (P < 0.01) after multiple dexamethasone than placebo courses, but apoptotic cell number did not differ. We conclude that nonneuronal apoptosis represents the major form of apoptosis in the CC at both 70% and 90% of gestation. Apoptosis in nonneuronal cells decreases with maturity and after a single course of dexamethasone at 70%, but not at 90%, gestation and not after multiple courses at 70% gestation. We speculate that a single course of glucocorticoids exerts maturational changes on the rate of apoptosis in the cerebral cortex of preterm ovine fetuses. © 2008 Wiley‐Liss, Inc.
Nitric oxide donor up‐regulation of SDF1/CXCR4 and Ang1/Tie2 promotes neuroblast cell migration after stroke
Authors: Cui Xu , Chen Jieli , Zacharek Alex , Roberts Cynthia , Yang Yuping , Chopp Michael 
Published: August 2008

AbstractWe tested the hypothesis that a nitric oxide donor, DETA‐NONOate, up‐regulates stromal cell‐derived factor‐1 (SDF1) and angiopoietin 1 (Ang1) in the ischemic brain and their respective receptors chemokine CXC motif receptor 4 (CXCR4) and Tie2 in the subventricular zone (SVZ) and thereby promote SVZ neuroblast cell migration after stroke. C57BL/6J mice were subjected to middle cerebral artery occlusion (MCAo), and 24 hr later DETA‐NONOate (0.4 mg/kg) or phosphate‐buffered solution was intravenously administered. Mice were sacrificed at 14 days for histological assessment or sacrificed at 3 days for analysis by real‐time polymerase chain reaction and migration after MCAo. To elucidate whether SDF1/CXCR4 and Ang1/Tie2 pathways mediate DETA‐NONOate‐induced SVZ migration after stroke, SDF1α, Ang1 peptide, a specific antagonist of CXCR4 (AMD3100), and a neutralizing antibody of Tie2 (anti‐Tie2) were used in vitro. DETA‐NONOate significantly increased the percentage area of doublecortin (DCX, a marker of migrating neuroblasts)‐immunoreactive cells in the SVZ and ischemic boundary zone. DETA‐NONOate significantly increased the expression of SDF1 and Ang1 in the ischemic border and up‐regulated CXCR4 and Tie2 in the SVZ compared with MCAo control. DCX‐positive cell migration from SVZ explants was significantly increased in the DETA‐NONOate treatment group compared with MCAo‐alone animals. In vitro, SDF1α and Ang1 significantly increased SVZ explants cell migration. In addition, inhibition of CXCR4 or Tie2 significantly attenuated DETA‐NONOate‐induced SVZ cell migration. Our data indicate that treatment of stroke with a nitric oxide donor up‐regulates SDF1/CXCR4 and Ang1/Tie2 pathways and thereby likely increases SVZ neuroblast cell migration. © 2008 Wiley‐Liss, Inc.
Immediate effects of prescribed burning, chopping and clearing on runoff, infiltration and erosion in a shrubland area in Galicia (NW Spain)
Authors: Fernández C. , Vega J. A. , Fonturbel T. , Jiménez E. , Pérez J. R. 
Published: August 2008

AbstractThe immediate effects of three different fuel management treatments on runoff, infiltration and erosion were evaluated in a mixed heathland in Galicia (NW Spain). The treatments compared were: prescribed burning, shrub chopping and shrub clearing.Rainfall simulations were conducted immediately before and after fuel reduction treatments. A rainfall rate of 67 mm h−1 was applied for 30 min to each runoff plot.Application of treatments significantly affected runoff and infiltration, but the parameter most affected by treatment was soil erosion, especially after prescribed burning. However, sediment yields measured immediately after treatments were low in all the cases, varying from 32 kg ha−1 after shrub clearing to 248 kg ha−1 after prescribed burning. In the rainfall simulation plots subjected to prescribed burning, the maximum temperatures reached at mineral soil surface during burns significantly affected soil losses. The organic layer remaining after treatments and soil moisture contents appeared to be critical variables in controlling runoff and erosion during the first rainfall event following fuel reduction treatments. When the remaining organic layer was removed just after treatments and a new rainfall simulation was carried out, mean infiltration rate trended to decrease and cumulative runoff and sediment yield tended to increase.The above information could be useful for determining whether fuel management prescriptions are compatible with fire hazard reduction and soil conservation. Copyright © 2008 John Wiley & Sons, Ltd.
Second order problems with functional conditions including Sturm–Liouville and multipoint conditions
Authors: Cabada Alberto , O'Regan Donal , Pouso Rodrigo L. 
Published: August 2008

AbstractIn this paper we study the solvability of equations of the form‐(d/dt)φ (t, u, u (t), u ′(t)) = f (t, u, u (t), u ′(t)) for a.e. t ∈ I = [a, b ],together with functional‐boundary conditions which cover, amongst others, Sturm–Liouville and multipoint boundary data as particular cases. Our approach uses upper and lower solutions together with growth restrictions of Nagumo's type. An example is presented to show the applicability of the obtained results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A unified approach for a class of problems involving a pseudo‐monotone operator
Authors: Jebelean Petru , Motreanu Dumitru , Motreanu Viorica Venera 
Published: August 2008

AbstractIn this paper we establish the solvability and approximation of a general inequality problem by means of a sequence of problems satisfying some compatibility conditions with respect to the initial one. The setting allows to unify and extend various existence results in the smooth and nonsmooth analysis. The approach mainly relies on Galerkin like approximations, pseudo‐monotone operators and topics from nonsmooth analysis. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optimal quantization for dyadic homogeneous Cantor distributions
Authors: Kreitmeier Wolfgang 
Published: August 2008

AbstractFor a large class of dyadic homogeneous Cantor distributions in ℝ, which are not necessarily self‐similar, we determine the optimal quantizers, give a characterization for the existence of the quantization dimension, and show the non‐existence of the quantization coefficient. The class contains all self‐similar dyadic Cantor distributions, with contraction factor less than or equal to 1/3. For these distributions we calculate the quantization errors explicitly. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boundedness of multilinear commutators of generalized fractional integrals
Authors: Mo Huixia , Lu Shanzhen 
Published: August 2008

AbstractLet L be the infinitesimal generator of an analytic semigroup on L2(ℝn ) with Gaussian kernel bound, and let L–α /2 be the fractional integral of L for 0 < α < n. Suppose that b = (b1, b2, …, bm ) is a finite family of locally integral functions, then the multilinear commutator generated by b and L–α /2 is defined byL–α /2bf = [bm , …, [b2, [b1, L–α /2]], …, ] f, where m ∈ ℤ+. When b1, b2, …, bm ∈ BMO or bj ∈ Λ (0 < βj < 1) for 1 ≤ j ≤ m, the authors study the boundedness of L–α /2b. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the principal eigenvalue of degenerate quasilinear elliptic systems
Authors: Zographopoulos Nikolaos B. 
Published: August 2008

AbstractWe study the properties of the positive principal eigenvalue of a degenerate quasilinear elliptic system. We prove that this eigenvalue is simple, unique up to positive eigenfunctions and isolated. Under certain restrictions on the given data, the regularity of the corresponding eigenfunctions is established. The extension of the main result in the case of an unbounded domain is also discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nonlinear Riemann–Hilbert problems with circular target curves
Authors: Glader Christer , Wegert Elias 
Published: August 2008

AbstractThe paper gives a systematic and self‐contained treatment of the nonlinear Riemann–Hilbert problem with circular target curves |w–c| =r, sometimes also called the generalized modulus problem. We assume thatcandrare Hölder continuous functions on the unit circle and describe the complete set of solutionswin the disk algebraH∞∩Cand in the Hardy spaceH∞of bounded holomorphic functions.The approach is based on the interplay with the Nehari problem of best approximation by bounded holomorphic functions. It is shown that the considered problems fall into three classes (regular, singular, and void) and we give criteria which allow to classify a given problem.For regular problems the target manifold is covered by the traces of solutions with winding number zero in a schlicht manner. Counterexamples demonstrate that this need not be so if the boundary condition is merely continuous.Paying special attention to constructive aspects of the matter we show how the Nevanlinna parametrization of the full solution set can be obtained from one particular solution of arbitrary winding number. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Expression Profile of pha Gene Cluster of Pseudomonas putida KT2442
Authors: de Eugenio Laura I. , Escapa Isabel F. , Galán Beatriz , García José L. , Prieto María A. 
Published: August 2008

AbstractPolyhydroxyalkanoates (PHAs) are biodegradable polymers that many bacteria accumulate as carbon and energy storage when growth conditions are unbalanced. Pseudomonas strains belonging to the rRNA homology group I such as P. putida can accumulate medium‐chain‐length‐PHA from monomers in the C8 to C10 range. Regulation of PHA synthesis and degradation in P. putida KT2442 has been studied using different molecular approaches. In this study six promoter regions located upstream of each pha gene were identified. The expression of the pha cluster have been analysed in the presence of octanoic acid versus glucose in the culture medium. Results demonstrated that the system is activated in the presence of octanoic acid as PHA precursor.
Conformational Dynamics of Poly(acrylic acid)‐Bovine Serum Albumin Polycomplexes at Different pH Conditions
Authors: Akkilic Namik , Mustafaev Mamed , Chegel Volodymyr 
Published: August 2008

AbstractThis work presents the real time surface plasmon resonance (SPR) and fluorescence spectroscopy observation of cooperative interactions between aggregate‐forming bovine serum albumin (BSA) and oppositely charged linear macromolecule poly(acrylic) acid (PAA). Interactions between protein and polymer result in formation of polyelectrolyte‐protein polycomplexes, which exhibit expressed conformational transformations, especially at low pH. The rate constants of observed kinetic transformations were calculated and found to vary in the range from 0.8 × 10−3 to 6.7 × 10−3 for different pH values. The processes of aggregation, sedimentation and conformation of BSA‐PAA complex are discussed.
Soybean allergen detection methods – A comparison study
Authors: Pedersen Mona H. , Holzhauser Thomas , Bisson Caroline , Conti Amedeo , Jensen Louise B. , Skov Per S. , Bindslev‐Jensen Carsten , Brinch Ditte S. , Poulsen Lars K. 
Published: August 2008

AbstractSoybean containing products are widely consumed, thus reliable methods for detection of soy in foods are needed in order to make appropriate risk assessment studies to adequately protect soy allergic patients. Six methods were compared using eight food products with a declared content of soy: a direct sandwich ELISA based on polyclonal rabbit antibody (ab) to raw soy flakes, a commercial and an in‐house competitive ELISA both based on ab to denatured, ‘renatured’ soy protein, an enzyme‐allergosorbent test (EAST) inhibition based on two sera from soy allergic patients, histamine release (HR) using basophils passively sensitized with patient serum and a PCR method detecting soy DNA. Eight food products were selected as model foods to test the performance of the methods. There was an overall good agreement between the methods in terms of ranks of soy content but not the quantity. The sandwich ELISA aimed at native soy proteins had the lowest detection limit of 0.05 ppm, but only identified soy in 5/8 products, and generally in lower amounts compared to other methods. The competitive ELISA had a higher detection limit of 21 ppm, but seemed more successful in detecting processed soy. Only HR, EAST inhibition and PCR detected soy in all eight products. In spite of a general good correlation in terms of ranks of soy content, more than a single method may be necessary to confirm the presence of soy in foods.
An error‐estimate‐free and remapping‐free variational mesh refinement and coarsening method for dissipative solids at finite strains
Authors: Mosler J. , Ortiz M. 
Published: August 2008

AbstractA variational h‐adaptive finite element formulation is proposed. The distinguishing feature of this method is that mesh refinement and coarsening are governed by the same minimization principle characterizing the underlying physical problem. Hence, no error estimates are invoked at any stage of the adaption procedure. As a consequence, linearity of the problem and a corresponding Hilbert‐space functional framework are not required and the proposed formulation can be applied to highly non‐linear phenomena. The basic strategy is to refine (respectively, unrefine) the spatial discretization locally if such refinement (respectively, unrefinement) results in a sufficiently large reduction (respectively, sufficiently small increase) in the energy. This strategy leads to an adaption algorithm having O(N) complexity. Local refinement is effected by edge‐bisection and local unrefinement by the deletion of terminal vertices. Dissipation is accounted for within a time‐discretized variational framework resulting in an incremental potential energy. In addition, the entire hierarchy of successive refinements is stored and the internal state of parent elements is updated so that no mesh‐transfer operator is required upon unrefinement. The versatility and robustness of the resulting variational adaptive finite element formulation is illustrated by means of selected numerical examples. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation of ion conductive inorganic–organic composite systems by in situ sol–gel reaction of polymerizable ionic liquids
Authors: Mizumo Tomonobu , Watanabe Takeshi , Matsumi Noriyoshi , Ohno Hiroyuki 
Published: August 2008

AbstractInorganic–organic composites that conduct lithium ions were prepared by in situ sol–gel processing, with polymerizable ionic liquids and functional silicate or borosilicate network. In the presence of lithium salts, radical polymerization of 1‐ethyl‐3‐vinylimidazolium bis(trifluoromethane sulfonyl) imide ([evim][Tf2N]) was performed in parallel with the hydrolysis/polycondensation reaction of tetramethoxysilane (TMOS) with various trialkoxyboranes such as trimethoxyboran (TMOB), triisopropoxyborane (TiPOB) or mesityldimethoxyborane (Mes‐DMOB). Many of the resulting composites were obtained as transparent or translucent glass‐like solids. The composites had high decomposition temperatures above 300°C, due to the high thermal stability of both the inorganic network and the polymerized ionic liquids. The ionic conductivity was increased by increasing the fraction of organic compounds. The ionic conductivity of the compound was also altered by the addition of LiTf2N, up to at least 10−5 S cm−1 at room temperature. The ionic conductivity of the LiSO3CF3 doped system was about one order of magnitude less than that. The ionic conductivity was found to be influenced by the boron content of the inorganic matrix. Interaction between the triflate anion and the empty p‐orbital of boron may enhance the salt dissociation. This interaction appears to increase the lithium ion transference number. In situ sol–gel processing is a valuable way to provide mechanical strength, as well as specific functions, of polymerized ionic liquids. Copyright © 2008 John Wiley & Sons, Ltd.
Synthesis, characterization, and electrorheological properties of polyindene/calcium carbonate composites
Authors: Sarikaya Seyma , Yavuz Mustafa , Yilmaz Hasim , Unal H. Ibrahim , Sari Bekir 
Published: August 2008

AbstractIn this study, synthesis, characterization, and electrorheological (ER) properties of polyindene (PIn) and PIn/calcium carbonate (PIn/CaCO3) conducting composites were carried out by free radical polymerization. In the experiments, FeCl3 was used as oxidizing agent and the ratio of salt:monomer was 2:1. First, PIn was synthesized and obtained with 70% yield. Then, PIn/CaCO3 composites containing various amounts of PIn were prepared. PIn and PIn/CaCO3 composites were characterized by FTIR spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), dynamic light scattering (DLS) methods, Gouy Balance, and dielectric measurements. Suspensions of PIn and PIn/CaCO3 composites were prepared in silicone oil (SO), at a series of concentrations (c = 10–25%, m/m) and their sedimentation stabilities were determined. The effects of dispersed particle concentration, particle size, shear rate, external electric field strength, frequency, and temperature onto ER activities of suspensions were investigated. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers
Structure and properties of starch nanocrystal‐reinforced soy protein plastics
Authors: Zheng Hua , Ai Fujin , Chang Peter R. , Huang Jin , Dufresne Alain 
Published: August 2008

AbstractPea starch nanocrystals (StNs) were incorporated into a soy protein isolate (SPI) matrix to produce a class of full‐biodegradable nanocomposites. The StN with low loading level (2 wt%) showed a predominant reinforcing function, resulting in an enhancement in strength and Young's modulus. This was attributed to uniform dispersion of StN in the amorphous region of the SPI matrix, as well as maintaining stress of the rigid StN and transfer of stress mediated by interfacial interaction between the active StN surface and the SPI matrix. As a result, the nanocomposite containing 2 wt% StN had the maximum strength and Young's modulus in all the materials. With an increase in StN content, the number and the size of StN domains simultaneously increased due to a strong self‐aggregation tendency of StN. It lowered the effective active StN surface for interaction with the SPI matrix and destroyed the ordered structure in the SPI matrix, resulting in a gradual decrease of strength and Young's modulus. The introduction of relatively hydrophilic StN did not cause an obvious decrease of water resistance for any of the nanocomposites. The water uptake behavior of all the nanocomposites similar to that of neat SPI material was attributed mainly to the strong interfacial interaction between the StN filler and the SPI matrix. POLYM. COMPOS., 2009. Published by the 2008 Society of Plastics Engineers