bluuebunny/crossref_metadata_2025 huggingface dataset:
Vitronectin is significant in the adhesion of lens epithelial cells to PMMA polymers
Authors: Evans Margaret D. M. , Pavon‐Djavid Graciela , Hélary Gérard , Legeais Jean‐Marc , Migonney Véronique
Published: April 2004

A major complication of intraocular lens surgery is diminished visual acuity caused by the regrowth of lens epithelial cells (secondary cataract). Polymethylmethacrylate (PMMA) is a commonly used intraocular lens material. This study addresses the mechanisms underlying the initial adhesion of lens epithelial cells to PMMA and a functionalized PMMA‐based terpolymer known to inhibit cell proliferation. Rabbit lens epithelial cells were cultured on the test polymer surfaces in medium containing serum depleted of either fibronectin or vitronectin (or both) to identify the role of these proteins in the initial process of cell adhesion. Adherent cells were quantitated after 60 min, and the actin cytoskeleton and focal contact formation were compared in each serum treatment on both polymers. Vitronectin was significantly more effective for initial cell attachment to both polymers than fibronectin. Normal cell spreading on PMMA required vitronectin and was independent of fibronectin, whereas cell spreading on the terpolymer was abnormal and required the presence of fibronectin and vitronectin together. Together, these results help to explain the inhibition of cell proliferation previously shown on the functionalized PMMA. This work contributes to the design of a polymer for use in intraocular lenses that inhibits proliferation of the target cells. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 69A: 469–476, 2004
Co‐operative effect of c‐Src and ezrin in deregulation of cell–cell contacts and scattering of mammary carcinoma cells
Authors: Elliott Bruce E. , Qiao Hui , Louvard Daniel , Arpin Monique
Published: April 2004

The non‐receptor tyrosine kinase c‐Src is activated in many human cancer types, and induces deregulation of cadherin‐based cell–cell contacts and actin cytoskeleton. Because ezrin, a protein which cross‐links the plasma membrane with the actin cytoskeleton, is often over‐expressed in human cancers, and participates in cell adhesion, motility, and cell scattering, we therefore investigated whether c‐Src co‐operates with ezrin in regulating cell–cell contacts in a murine mammary carcinoma cell line, SP1. SP1 cells over‐expressing wild type ezrin, or an activated c‐Src mutant, formed loose aggregates which scattered spontaneously when plated on plastic. When wild type ezrin and activated c‐Src were co‐expressed, scattering was increased, cell–cell contacts disrupted, and cell aggregation prevented. Pre‐treatment with the c‐Src family kinase inhibitor PP2 partially restored aggregation of cells expressing activated c‐Src and wild type ezrin, indicating that c‐Src family kinases act co‐operatively with ezrin in regulating cell–cell contacts. Furthermore, expression of a truncated NH2‐terminal domain of ezrin, which has dominant negative function, blocked the cell scattering effect of activated c‐Src and promoted formation of cohesive cell–cell contacts. Together, these results suggest co‐operativity between c‐Src and ezrin in deregulation of cell–cell contacts and enhancing scattering of mammary carcinoma cells. © 2004 Wiley‐Liss, Inc.
Estrogen stimulates differentiation of megakaryocytes and modulates their expression of estrogen receptors α and β
Authors: Bord Sharyn , Frith Emma , Ireland Deborah C. , Scott Mike A. , Craig Jenny I.O. , Compston Juliet E.
Published: April 2004

Estrogen has multifunctional effects influencing growth, differentiation, and function in many tissues. High‐dose estrogen has been shown to produce anabolic skeletal effects in the skeleton of postmenopausal women with increased megakaryocyte (MK) population in the bone marrow, suggesting a possible role for these cells in bone remodelling. To investigate if estrogen stimulates megakaryocytopoiesis and affects on estrogen receptor (ER) expression, CD34(+) cells were cultured for 6, 9, and 14 days plus or minus low‐dose or high‐dose 17β estradiol (E). Cells were immunolocalised for CD61, CD41, ERα and β. ER mRNA expression was assessed by RT‐PCR. Cells formed more CD61 positive MK colonies with low‐ and high‐dose E treatment (P < 0.001) at 6 and 9 days. CD41 expression was increased dose‐dependently in MK (3‐ and 5‐fold P < 0.001) at 9 days. E‐stimulated ERα expression at 6 days (P < 0.001) whilst ERβ was dose‐dependently increased only at 9 days (P < 0.01). ERα mRNA was increased at 6 days but not at 14 days whilst ERβ mRNA expression was only increased at 14 days with E treatment. These results demonstrate that E stimulates the colony forming potential of CD34(+) cells to a more megakaryocytic phenotype in vitro. This finding together with the stimulation of ER protein and mRNA expression adds to the increasing evidence for a role for MKs in estrogen‐induced bone formation. © 2004 Wiley‐Liss, Inc.
TBX5, a gene mutated in Holt–Oram syndrome, is regulated through a GC box and T‐box binding elements (TBEs)
Authors: Sun Guifeng , Lewis Lisa E. , Huang Xu , Nguyen Quang , Price Christopher , Huang Taosheng
Published: April 2004

TBX5 is a member of the T‐box gene family and encodes a transcription factor that regulates the expression of other gene(s) in the developing heart and limbs. Mutations of TBX5 cause Holt–Oram syndrome (HOS), an autosomal dominant condition characterized by congenital heart defects and limb anomalies. How TBX5 gene expression is regulated is still largely unknown. In order to identify transcription factors regulating TBX5 expression, we examined the 5′‐flanking region of the human TBX5 gene. We determined that up to 300 bp of the 5′‐flanking region of the TBX5 gene was necessary for promoter activity in mouse cardiomyocyte ECL2 cells. One GC box, three potential T‐box‐like binding elements (TBE‐A, ‐B, and ‐C), and one NKX2.5 binding site were identified. Site‐directed mutagenesis of the potential binding sites revealed that the GC box, TBE‐B, TBE‐C, and NKX2.5 are functionally positive for the expression of TBX5. DNA footprint analysis showed that these binding regions are resistant to DNaseI digestion. Electrophoretic mobility shift assays (EMSAs) further demonstrated the protein–DNA interactions at the GC box and the potential TBE‐B, TBE‐C, and NKX2.5 sites in a sequence‐specific manner. The ability of TBX5 to regulate its own promoter was demonstrated by the ability of ectopically expressed human TBX5 to increase reporter expression. We conclude that the GC box, T‐box‐like binding elements, and NKX2.5 binding site play important roles in the regulation of TBX5 expression, and that TBX5 is likely to be autoregulated as part of the mechanism of its transcription. © 2004 Wiley‐Liss, Inc.
Expression of Nox4 in osteoclasts
Authors: Yang Su , Zhang Yizhong , Ries William , Key Lyndon
Published: April 2004

A new superoxide‐generating enzyme, NADPH oxidase 4 (Nox4), contributes to osteoclastic superoxide production. In this study, we demonstrated that Nox4 is expressed at a higher level in osteoclasts than that in precursor cells. This result suggested that Nox4 is upregulated during the differentiation and development of osteoclasts. Cotransfection of Nox4/P22 DNA resulted in enhanced superoxide production in osteoclasts, indicating that P22 may be a necessary factor for the Nox4 activity. In addition, expression of both cathepsin K and TRAP is increased significantly in osteoclasts cotransfected with Nox4/P22. Further study revealed that JNK was activated and that NF‐κB was inhibited in Nox4/P22 cotransfected osteoclasts. These findings suggest that superoxide and/or superoxide derived molecules may modulate the signal transduction pathways necessary for osteoclasts to function. © 2004 Wiley‐Liss, Inc.
C‐terminal region of protein kinase CK2α: How the structure can affect function and stability of the catalytic subunit
Authors: Grasselli Elena , Tomati Valeria , Bernasconi Marco V. , Nicolini Claudio , Vergani Laura
Published: April 2004

A novel mutant of the catalytic α subunit of human protein kinase CK2 (CK2α) was designed in an attempt to clarify the role of the carboxylic‐terminal segment characteristic of vertebrates, excluding fish. Starting from the sequence alignments, we constructed a phylogenetic tree of the primary structure of CK2α. On this basis, we substituted two distal prolines with alanines (PA 382‐384). Theoretical calculations and spectropolarimetry measurements, performed both on native and mutant subunits, indicate an increased content of α‐helix after this double amino acidic substitution. In order to clarify the structure/function relationship of the C‐terminal region, we verified if the structural change affects the catalytic activity of CK2α. The mutant exhibits slightly increased phosphorylation efficiency, but reduced ability to transfer phosphate in comparison with the native subunit. At last, we compared the thermal stability of the mutant with respect to the native subunit and we tested the proteolytic degradability. The observation that the PA 382‐384 mutant exhibits an increased thermal and proteolytic stability suggests that this mutant could be employed to solve the three‐dimensional (3D) structure of human CK2α and to overcome difficulties in crystallizing the native form. © 2004 Wiley‐Liss, Inc.
Anti‐apoptotic effects of curcumin on photosensitized human epidermal carcinoma A431 cells
Authors: Chan Wen‐Hsiung , Wu Hsin‐Jung
Published: April 2004

Photodynamic treatment (PDT) can elicit a diverse range of cellular responses, including apoptotic cell death. Previously, we showed that PDT stimulates caspase‐3 activation and subsequent cleavage and activation of p21‐activated kinase 2 (PAK2) in human epidermal carcinoma A431 cells. Curcumin, the yellow pigment of Curcuma longa, is known to have anti‐oxidant and anti‐inflammatory properties. In the present study, using Rose Bengal (RB) as the photosensitizer, we investigated the effect of curcumin on PDT‐induced apoptotic events in human epidermal carcinoma A431 cells. We report that curcumin prevented PDT‐induced JNK activation, mitochondrial release of cytochrome c, caspase‐3 activation, and cleavage of PAK2. Using the cell permeable dye DCF‐DA as an indicator of reactive oxygen species (ROS) generation, we found that both curcumin and ROS scavengers (i.e., l‐histidine, a‐tocopherol, mannitol) abolished PDT‐stimulated intracellular oxidative stress. Moreover, all these PDT‐induced apoptotic changes in cells could be blocked by singlet oxygen scavengers (i.e., l‐histidine, a‐tocopherol), but were not affected by the hydroxyl radical scavenger mannitol. In addition, we found that SP600125, a JNK‐specific inhibitor, reduced PDT‐induced JNK activation as well as caspase‐3 activation, indicating that JNK activity is required for PDT‐induced caspase activation. Collectively, these results demonstrate that singlet oxygen triggers JNK activation, cytochrome c release, caspase activation and subsequent apoptotic biochemical changes during PDT and show that curcumin is a potent inhibitor for this process. © 2004 Wiley‐Liss, Inc.
Sampling protein conformations and pathways
Authors: Lei Ming , Zavodszky Maria I. , Kuhn Leslie A. , Thorpe M. F.
Published: April 2004

Protein flexibility and rigidity can be analyzed using constraint theory, which views proteins as 3D networks of constraints involving covalent bonds and also including hydrophobic interactions and hydrogen bonds. This article describes an algorithm, ROCK (Rigidity Optimized Conformational Kinetics), which generates new conformations for these complex networks with many interlocked rings while maintaining the constraints. These new conformations are tracked for the flexible regions of a protein, while leaving the rigid regions undisturbed. An application to HIV protease demonstrates how large the flap motion can be. The algorithm is also used to generate conformational pathways between two distinct protein conformations. As an example, directed trajectories between the closed and the occluded conformations of the protein dihydrofolate reductase are determined. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1133–1148, 2004
Some remarks on domination
Authors: Archdeacon D. , Ellis‐Monaghan J. , Fisher D. , Froncek D. , Lam P.C.B. , Seager S. , Wei B. , Yuster R.
Published: April 2004

We prove a conjecture of Favaron et al. that every graph of order n and minimum degree at least three has a total dominating set of size at least n/2. We also present several related results about: (1) extentions to graphs of minimum degree two, (2) examining graphs where the bound is tight, and (3) a type of bipartite domination and its relation to transversals in hypergraphs. © 2004 Wiley Periodicals, Inc. J Graph Theory 46: 207–210, 2004
Edge colorings of complete graphs without tricolored triangles
Authors: Gyárfás András , Simony Gábor
Published: April 2004

We show some consequences of results of Gallai concerning edge colorings of complete graphs that contain no tricolored triangles. We prove two conjectures of Bialostocki and Voxman about the existence of special monochromatic spanning trees in such colorings. We also determine the size of largest monochromatic stars guaranteed to occur. © 2004 Wiley Periodicals, Inc. J Graph Theory 46: 211–216, 2004
Effects of phosphorus and zinc fertilizer on cadmium uptake and distribution in flax and durum wheat
Authors: Jiao You , Grant Cynthia A , Bailey Loraine D
Published: April 2004

Cadmium accumulation in crops presents a potential risk to human health. To understand the difference between dicotyledonous and monocotyledonous species in respect of Cd accumulation, and to develop fertilizer management practices to minimise Cd uptake, a growth chamber study was conducted to evaluate the interactive effects of Cd concentration in phosphate and Zn fertilizer on Cd uptake in flax (Linum usitatissimum L) and durum wheat (Triticum turgidum L). Cadmium concentration was higher in flax than durum wheat shoots. Cadmium concentration was lower and Zn concentration higher in the flax seed and durum wheat grain than in the root, shoot or straw of both species. These results suggest that flax has comparatively ineffective barriers discriminating against the transport of Cd from the root to the shoot via the xylem, and that both crops may restrict Cd translocation to the seed/grain via the phloem. Commercial grade monoammonium phosphate (NH4H2PO4) or triple superphosphate (Ca(H2PO4)2) produced higher seed Cd concentrations than did reagent grade P in flax but not in durum wheat. Application of P significantly decreased seed/grain Zn concentration and increased seed/grain Cd concentration. Zinc addition at 20 mg Zn kg−1 soil with P decreased seed/grain Cd concentration (average 42.2% for flax, 65.4% for durum wheat), Cd accumulation (average 37.2% for flax, 62.4% for durum wheat) and Cd translocation to the seed/grain (average 20.0% for flax, 34.5% for durum wheat) in both crops. These results indicate that there is an antagonistic effect of Zn on Cd for root uptake and distribution within the plant. Copyright © 2004 Society of Chemical Industry
Effect of different packing treatments on the microbiological and physicochemical characteristics of untreated green olives of the Conservolea cultivar
Authors: Panagou Efstathios Z
Published: April 2004

Microbiological, physicochemical and organoleptic changes were studied in non‐pasteurised samples of untreated green olives cv Conservolea stored at 20 °C for 180 days under different preservation treatments (acidified brine and modified atmospheres). The microbial flora consisted of lactic acid bacteria and yeasts, while no enterobacteria and pseudomonads were enumerated in any package. Although no thermal treatment was applied to the packages, no sediment formation was observed due to the growth of propionic bacteria. Olives packed in brine supplemented with 0.3% lactic and 0.3% citric acids presented the highest acidity, the lowest brine and flesh pH and the lowest dark brine colour as measured by the parameter A440−A700. Olives packed in modified atmospheres (vacuum, 40% CO2/30% O2/30% N2 and air) presented a progressive loss of fruit firmness and colour with time. At the end of the storage period, olives packed in aerobic conditions and 40% CO2/30% O2/30% N2 presented the lowest firmness and skin colour and were unacceptable to the panellists. The best quality characteristics were maintained in vacuum‐packed olives, as indicated by the higher organoleptic scores. Firmness degradation followed first‐order kinetics (r2 > 0.980) and the expected shelf‐life was 23, 15 and 9 months for olives packed in vacuum, 40% CO2/30% O2/30% N2 and air respectively. Copyright © 2004 Society of Chemical Industry
Synthesis and Characterisation of Side‐Chain Liquid Crystalline Poly[1‐({[(4‐cyano‐4′‐biphenyl)oxy]alkyl}oxy)‐2,3‐epoxypropane]
Authors: Han Xiangen , Shanks Robert A. , Pavel Dumitru
Published: April 2004

Summary: A new series of side‐chain liquid‐crystal polymers, the poly[1‐({[(4‐cyano‐4′‐biphenyl)oxy]alkyl}oxy)‐2,3‐epoxypropane], has been synthesized in which the spacer length is varied from 2 to 8 methylene units. The synthesis used for the chemical modification of polyepichlorohydrin (PECH) involved the phase transfer catalyzed etherification of the chloromethyl groups with sodium 4‐cyano‐4′‐biphenoxide and lithium n‐(4‐cyano‐4′‐oxybiphenyl)‐alkanoates. All the resulting polymers (except polymers 7 and 8), including that without spacer, characterized by 1H NMR, and IR, exhibit thermotropic liquid crystalline mesomophism. The thermal behavior of the polymers has been characterized using differential scanning calorimetry (DSC) and polarized light microscopy (POM) equipped with hot‐stage. A more pronounced odd‐even effect in the clearing temperatures is observed on increasing the spacer length in which the odd members display slightly higher values, which were also dependent on the substitution degree of PECH. The flexible PECH chain assists nematic LC formation compared with other more rigid backbone polymers where a smectic phase is often encountered with the same mesogen. A comparison of the thermal properties of the cyanobiphenyl based series reported here. Polyacrylate (PA) and poly(methacrylate)‐based (PMA) SCLCPs containing 4‐cyanobiphenyl as the mesogenic unit are consistent with the general rule that increasing backbone flexibility for a given mesogenic unit and spacer length enhance the clearing temperature. This was not found from the PECH‐based series, which show the lower clearing temperature than the PMA and PA series, even though they have more flexible backbone than PA and PMA series. So the clearing temperature is not solely determined by the flexibility of the backbone.

Schlieren textures of PECHOC2‐B taken at 110 °C (cooling from isotropic phase after annealing 1 h).

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Schlieren textures of PECHOC2‐B taken at 110 °C (cooling from isotropic phase after annealing 1 h).
Variation on a theme of Schütte
Authors: Jäger Gerhard , Probst Dieter
Published: April 2004

Let ≺ be a primitive recursive well‐ordering on the natural numbers and assume that its order‐type is greater than or equal to the proof‐theoretic ordinal of the theory T. We show that the proof‐theoretic strength of T is not increased if we add the negation of the statement which formalizes transfinite induction along ≺. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
N,N‐Dimethylformamide Additions to the Solution for the Electrospinning of Poly(ε‐caprolactone) Nanofibers
Authors: Hsu Chen‐Ming , Shivkumar Satya
Published: April 2004

Summary: Additives that exhibit polyelectrolyte behavior such as N,N‐dimethylformamide (DMF) may improve the electrospinning characteristics of viscoelastic polymer solutions. DMF additions to the solution lead to extensive jet splaying, thereby reducing the fiber diameter significantly. Nanofibrous structures with diameters of the order of 150 nm can be produced by the addition of about 10 vol.‐% DMF to the solvent (chloroform). DMF additions also yield a narrow, unimodal distribution of fibers, compared to the bimodal distribution typically detected in electrospun polymers.

Jet breakdown without (left) and with DMF addition to the solution.

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Jet breakdown without (left) and with DMF addition to the solution.
Morphology and Tensile Strength Prediction of in situ Microfibrillar Poly(ethylene terephthalate)/Polyethylene Blends Fabricated via Slit‐Die Extrusion‐Hot Stretching‐Quenching
Authors: Li Zhong‐Ming , Yang Wei , Xie Bang‐Hu , Shen Kai‐Zhi , Huang Rui , Yang Ming‐Bo
Published: April 2004

Summary: In situ microfibrillar poly(ethylene terephthalate) (PET)/polyethylene blends (MRB) were successfully fabricated by slit‐die extrusion‐hot stretching‐quenching. The morphology of this new material is mainly influenced by the composition and the hot stretching. Appropriate PET concentrations and a comparatively high hot stretching ratio could facilitate the fibrillation of PET domains during processing. The expression employed for prediction of the tensile strength for the microfibrillar blend was proved to be desirable. The prediction was, generally, in agreement with the experimental results, although the values of some parameters were approximated.

SEM micrograph of the cryofractured surface of the in situ microfibrillar PET/PE blend after injection molding.

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SEM micrograph of the cryofractured surface of the in situ microfibrillar PET/PE blend after injection molding.
Preparation and Combustion Properties of Flame Retardant Styrene‐Butyl Acrylate Copolymer/Graphite Oxide Nanocomposites
Authors: Zhang Rui , Hu Yuan , Xu Jiayan , Fan Weicheng , Chen Zuyao , Wang Qinan
Published: April 2004

Summary: Styrene‐butyl acrylate copolymer (St‐BA)/graphite oxide (GO) nanocomposites and St‐BA/GO/MPP [melamine poly(metaphosphate)] composites were prepared via an intercalation process by the ball‐milling method and characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), and field emission scanning electron microanalyzer (SEM). Cone calorimetry experiments were carried out to evaluate their flammability. The cone calorimetry data suggested that the addition of GO can decrease the heat release rate of St‐BA copolymers significantly. Furthermore, there was also a synergistic effect on the fire retardant property by the combination of GO and MPP. However, no prominent effect of the GO content on the reduction of peak heat release rate (HRR) in nanocomposites could be found.

SEM image of the fractured surface of St‐BA/GO/MPP hybrid.

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SEM image of the fractured surface of St‐BA/GO/MPP hybrid.
A Kinetic Study on the Thermal Degradation of Multi‐Walled Carbon Nanotubes‐Reinforced Poly(propylene) Composites
Authors: Seo Min‐Kang , Park Soo‐Jin
Published: April 2004

Summary: The influence of the multi‐walled carbon nanotubes (MWNTs) content on the thermal degradation behavior of MWNTs‐reinforced poly(propylene) (PP) composites was investigated by using non‐isothermal thermogravimetric analysis (TGA). Kinetic parameters of degradation were evaluated by using the Flynn‐Wall‐Ozawa iso‐conversional method and the pseudo first‐order method. As a result, compared with pristine PP, MWNTs‐PP nanocomposites have lower peak temperatures of degradation, narrower degradation temperature ranges and a higher amount of residual weight at the end of the degradation, which is likely to be a result of specific interactions between complimentary functional groups. The values of the reaction order of MWNTs‐PP nanocomposites determined by the Kissinger method are close to 1 in the non‐isothermal degradation process. There is a good correlation between the Ea in region II and the peak temperature of degradation for the composites.

Activation energies for degradation of different contents of MWNTs‐filled PP nanocomposites as a function of conversion.

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Activation energies for degradation of different contents of MWNTs‐filled PP nanocomposites as a function of conversion.
Structure and Mechanical Properties of Composites of Poly(6‐hexanelactam) Combining Solid Tribological Additives and Reinforcing Components
Authors: Horský Jaroslav , Kolařík Jan , Fambri Luca
Published: April 2004

Summary: Three types of composites of polyamide 6 (PCL) with hybrid tribological additives were synthesized via anionic adiabatic “in situ” polymerization of 6‐hexanelactam (ε‐caprolactam) initiated with metallic sodium and activated with either cyclic trimer of phenyl isocyanate or diphenylmethane 4,4′‐diisocyanate. Combinations of the additives and their maximum applied concentrations (in wt.‐%) were the following: MoS2/graphite(G)/oil(O) (5/16/9), short carbon fibers (CF)/G/O (5/20/10), and copper phthalocyanine (CPC) (7). Dynamic mechanical thermal analysis (DMTA) indicates a secondary (β) transition at about −65 °C and the main (α) transition at temperatures close to 20 °C; the storage modulus passes through a shallow maximum as a function of the total content of additives. Tensile creep and indentation creep concurrently evidenced some increase in compliance with rising fraction of incorporated compounds. Stress‐strain tests in flexure show that flexural strength and toughness monotonically decreased with the content of MoS2/G/O or CF/G/O, whereas the flexural modulus passed through a flat maximum. On the other hand, the strength and modulus were decreasing with CPC content, while toughness and Charpy impact tests showed some improvement.

Flexural toughness afU as a function of filler content Cad in adiabatic anionic polymerization of 6‐hexanelactam.

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Flexural toughness afU as a function of filler content Cad in adiabatic anionic polymerization of 6‐hexanelactam.
Simple and Fast Organic Device Encapsulation Using Polyisobutene
Authors: Toniolo Rogério , Hümmelgen Ivo A.
Published: April 2004

Summary: We demonstrate the use of polyisobutene (PIB) in a glass encapsulation method suitable for organic devices. The PIB viscosity at environmental temperatures provides a fast and non‐aggressive passivant layer formation method for device protection with glass. Due to its fully aliphatic character, PIB is suitable for passivating organic light‐emitting and photovoltaic devices. The observed preservation of encapsulated Ca films demonstrates the PIB suitability for air‐unstable metals passivation. Stable I(V) characteristics and increased operational lifetime were observed in PIB‐encapsulated organic devices. This encapsulation method is cheap, simple, and dispenses intensive equipment use, so that it is appropriate even for laboratories with restricted experimental facilities.

Setup used for Ca samples testing. The right Ca contact was encapsulated with PIB and a glass cover plate (dashed square). The electrical diagram of the apparatus used to obtain the resistance behavior is also shown.

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Setup used for Ca samples testing. The right Ca contact was encapsulated with PIB and a glass cover plate (dashed square). The electrical diagram of the apparatus used to obtain the resistance behavior is also shown.
Riesz potential and Sobolev embeddings on generalized Lebesgue and Sobolev spaces Lp(·) and Wk,p(·)
Authors: Diening Lars
Published: April 2004

We study the Riesz potentials Iαf on the generalized Lebesgue spaces Lp(·)(ℝd), where 0 < α < d and Iαf(x) ≔ ∫ |f(y)| |x – y|α – d dy. Under the assumptions that p locally satisfies |p(x) – p(x)| ≤ C/(– ln |x – y|) and is constant outside some large ball, we prove that Iα : Lp(·)(ℝd) → Lp♯(·)(ℝd), where $ {\textstyle {1 \over {p ^{\sharp} (x)}} = {1 \over {p(x)}} - {\alpha \over d}} $. If p is given only on a bounded domain Ω with Lipschitz boundary we show how to extend p to $ \tilde p $ on ℝd such that there exists a bounded linear extension operator ℰ : W1,p(·)(Ω) ↪ $ W^{1, {\tilde p}} $(ℝd), while the bounds and the continuity condition of p are preserved. As an application of Riesz potentials we prove the optimal Sobolev embeddings Wk,p(·)(ℝd) ↪Lp*(·)(Rd) with $ {\textstyle {1 \over {p ^{\ast} (x)}} = {1 \over {p(x)}} - {k \over d}} $ and W1,p(·)(Ω) ↪ Lp*(·)(Ω) for k = 1. We show compactness of the embeddings W1,p(·)(Ω) ↪ Lq(·)(Ω), whenever q(x) ≤ p*(x) – ε for some ε > 0. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Harmonic functions on the real hyperbolic ball II Hardy‐Sobolev and Lipschitz spaces
Authors: Grellier Sandrine , Jaming Philippe
Published: April 2004

In this paper, we pursue the study of harmonic functions on the real hyperbolic ball started in [13]. Our focus here is on the theory of Hardy‐Sobolev and Lipschitz spaces of these functions. We prove here that these spaces admit Fefferman‐Stein like characterizations in terms of maximal and square functionals. We further prove that the hyperbolic harmonic extension of Lipschitz functions on the boundary extend into Lipschitz functions on the whole ball. In doing so, we exhibit differences of behaviour of derivatives of harmonic functions depending on the parity of the dimension of the ball and on the parity of the order of derivation. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Boundedness in nonlinear oscillations
Authors: Yang Xiaojing
Published: April 2004

In this paper, the boundedness of all solutions of the nonlinear differential equation

(φp(x′))′ + αφp(x+) – βφp(x–) + f(x) = e(t)

is studied, where φp(u) = |u|p–2 u, p ≥ 2, α, β are positive constants such that $ \alpha ^{-{1 \over p}} + \beta ^{-{1 \over p }} $ = 2w–1 with w ∈ ℝ+\ℚ, f is a bounded C5 function, e(t) ∈ C6 is 2πp‐periodic, x+ = max{x, 0}, x– = max{–x, 0}. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stereospecific Polymerization of Isoprene with Nd(BH4)3(THF)3/MgBu2 as Catalyst
Authors: Bonnet Fanny , Visseaux Marc , Pereira Angela , Bouyer Frédéric , Barbier‐Baudry Denise
Published: April 2004

Summary: The neodymium trisborohydride Nd(BH4)3(THF)3 (THF = tetrahydrofuran) has been used as a catalyst precursor for isoprene polymerization for the first time. Associated to an excess of Al(Et)3, the resulting catalyst is moderately active, giving a mixture of cis‐ and trans‐ polymer. Addition of a stoichiometric amount of MgBu2 to Nd(BH4)3(THF)3 affords a stereospecific catalyst providing trans‐1,4‐polyisoprene, more than 96% regular. That dual component Nd/Mg system also shows a better efficiency and good control of the molecular weights. A molecular structure is tentatively attributed to a bimetallic active species, based on 1H NMR experiments.

Possible Nd/Al and Nd/Mg active initiating species.

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Possible Nd/Al and Nd/Mg active initiating species.
Two siblings with homocystinuria presenting with dystonia and parkinsonism
Authors: Ekinci Burçak , Apaydin Hulya , Vural Melih , Özekmekçi Sibel
Published: April 2004

Movement disorders such as dystonia, chorea or tremor are rarely encountered in patients with homocystinuria. We present 2 siblings with laboratory‐confirmed homocystinuria, one with severe generalized dystonia and the other with mild parkinsonism. The movement disorders in our patients appeared in the second and first decades, respectively. © 2004 Movement Disorder Society
Parkinson's disease‐like presentation of multiple system atrophy with poor response to STN stimulation: A clinicopathological case report
Authors: Lezcano Elena , Gómez‐Esteban Juan C. , Zarranz Juan J. , Alcaraz Rafael , Atarés Begoña , Bilbao Gaizka , Garibi Jesús , Lambarri Imanol
Published: April 2004

We report on a clinicopathological case of multiple system atrophy with good response to levodopa and subsequent development of motor complications. Because the subject complied with all the inclusion criteria (Core Assessment Program for Surgical Interventional Therapies in Parkinson's Disease), bilateral subthalamic nucleus deep brain stimulation electrodes were implanted. © 2004 Movement Disorder Society
Fracture of the odontoid process complicating tardive dystonia
Authors: Konrad Carsten , Vollmer‐Haase Juliane , Gaubitz Markus , Nabavi Darius G. , Reilmann Ralf , Knecht Stefan
Published: April 2004

We report on a 57‐year‐old woman with frequent and powerful retrocollis. The involuntary movements combined with rheumatoid arthritis and osteoporosis led to a fracture of the axial odontoid process. Neurologists with a focus on movement disorders should screen for diseases putting the patient at risk for spinal lesions and consider early treatment. © 2004 Movement Disorder Society
Adrafinil‐induced orofacial dyskinesia
Authors: Thobois Stéphane , Xie Jing , Mollion Helena , Benatru Isabelle , Broussolle Emmanuel
Published: April 2004

We describe the first case of orofacial abnormal movements induced by adrafinil, a vigilance promoting agent of the same pharmacological class as modafinil. The dyskinesias did not spontaneously recover despite adrafinil withdrawal for a 4‐month period. They were secondly dramatically improved by tetrabenazine, a presynaptic dopaminergic depleting drug which was introduced after the 4‐month adrafinil‐free period. © 2004 Movement Disorder Society
Cyclooxygenase and 5‐lipoxygenase pathways in the vessel wall: Role in atherosclerosis
Authors: Vila Luís
Published: April 2004

Prostaglandins (PGs), thromboxanes (Txs), and leukotrienes (LTs) play a relevant role in cardiovascular physiology and pathophysiology. Recent reports concerning cardiovascular risk associated with cyclooxygenase‐2 selective inhibitors have prompted questions about the “protective” or “deleterious” role of each COX isoform in cardiovascular disease, and the cloning and expression of inducible PGE‐synthase (PGES) open the possibility that PGES could be a new therapeutical target in this context. Predominance of constricting or relaxing prostanoids depends not only on COX activity but also to downstream enzymes such as PGI‐synthase (PGIS) and PGES. In the vessel wall, PGIS and PGES seem to be major downstream enzymes in the endothelium and smooth muscle, respectively. Like COX, activity of these enzymes can also be regulated by several factors, which include nitrogen oxides, cytokines, and lipid peroxides. LTs are important inflammatory mediators also involved in the pathophysiology of cardiovascular disease, which are targets for pharmacological intervention. Unlike COX pathway, the biosynthesis of chemotactic and vaso‐constrictor LTs in the vasculature strongly depends on leukocyte recruitment and activation, and on cell‐cell interaction between leukocytes and vascular cells in the inflamed areas. The present review emphasizes the role of vascular‐derived prostanoids and LTs on atherosclerosis. © 2004 Wiley Periodicals, Inc. Med Res Rev, 24, No. 4, 399–324, 2004
Governance for sustainable poverty reduction: the social fund in Nicaragua
Authors: Dijkstra A. Geske
Published: April 2004

Like other social funds, the Nicaraguan Emergency Social Investment Fund (FISE) has been created on the initiative of the donors to alleviate the social consequences of adjustment policies. It finances small infrastructural projects in education, health, water and other sectors and focuses on poor communities. FISE accounts for approximately 11% of public investment and 48% of public investment in the social sectors. The size of FISE and its apparent permanent character raise questions of its contribution to sustainable poverty reduction and on institutional development in the country. The article concludes that there are serious doubts on whether maintaining a social fund as a separate agency enhances effective governance for sustainable poverty reduction. Copyright © 2004 John Wiley & Sons, Ltd.
Scaling‐up participation at USAID
Authors: Corneille Faith , Shiffman Jeremy
Published: April 2004

Since the 1970s many non‐governmental development organisations have moved away from top‐down modes of operation toward participatory practices that hand over decision‐making power to the poor. The bilateral development agencies of the industrialised states have been slower to follow suit, but in the 1980s and 1990s a number of such agencies also initiated participatory‐oriented reforms. Development scholars have paid little attention to reforms of the larger organisations. In this article, we analyse the efforts of the United States Agency for International Development to embrace participation in the 1990s. Internal reformers managed to change some agency procedures but had only limited success in institutionalising participatory practices. Forces internal to the agency, including rigid rules and employee incentive structures, hampered reform efforts. Also, while some developments external to the agency facilitated participation, many others, including legislative interference and shifting national policy priorities, hindered change toward participation. The case reveals how complex webs of accountability relationships make participatory‐oriented transformation a cumbersome process in large development organisations. Change towards participation can succeed, but only if reformers acknowledge and consider existing institutional constraints. Copyright © 2004 John Wiley & Sons, Ltd.
Allelic length of a CA dinucleotide repeat in the egfr gene correlates with the frequency of amplifications of this sequence—first results of an inter‐ethnic breast cancer study
Authors: Buerger Horst , Packeisen Jens , Boecker Almuth , Tidow Nicola , Kersting Christian , Bielawski Krzysztof , Isola Jorma , Yatabe Yasushi , Nakachi Kei , Boecker Werner , Brandt Burkhard
Published: April 2004

Overexpression of the epidermal growth factor receptor (EGFR) is a common finding in invasive breast cancer and represents a potential target for new treatment options. However, little is known about the parameters that might indicate a potential clinical response for these anti‐EGFR‐based therapies. In order to gain further insights into the interplay between the length of a CA‐SSR I repeat in intron 1 of egfr, copy numbers of this untranslated regulatory sequence, and protein expression, the present study investigated breast cancers from Germans and Japanese patients by microsatellite analysis, quantitative 5′ nuclease assay by egfr enzyme‐linked immunosorbent assay (ELISA), and comparative genomic hybridization (CGH). Japanese breast cancer patients displayed significantly longer alleles for the CA‐SSR I repeat (p < 0.001), associated with significantly lower EGFR expression (mean 65 versus 36 fmol/mg membrane protein). Allelic imbalance (restricted to CA‐SSR I) was observed in 55% of the informative Japanese breast cancers compared with only 34% of the German breast cancer reference group. Using a quantitative 5′ nuclease assay for egfr, a significantly higher percentage of Japanese breast cancer patients revealed amplifications of the CA‐SSR I repeat (p < 0.01). Japanese patients with these amplifications were characterized by a significantly higher EGFR content compared with the German breast cancer patients (p < 0.05). These data show, on the one hand, that the correlation of EGFR overexpression and an inherited CA repeat polymorphism within intron 1 of egfr is a general finding in breast cancer, as has been shown previously. On the other hand, the data demonstrate clearly for the first time an interaction between the length of a polymorphism in intron 1 of egfr as an inherited genetic factor and the frequency of egfr amplification, as an acquired genetic factor, both factors contributing to EGFR overexpression in breast cancer. This new knowledge about mechanisms of regulation of EGFR expression might serve as an additional basis for evaluating anti‐EGFR‐based therapies. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Expression of regulator of G protein signalling protein 5 (RGS5) in the tumour vasculature of human renal cell carcinoma
Authors: Furuya Mitsuko , Nishiyama Mariko , Kimura Sadao , Suyama Takahito , Naya Yukio , Ito Haruo , Nikaido Takashi , Ishikura Hiroshi
Published: April 2004

The gene expression profiles of tumour and normal vasculature are distinctively different. The altered expression of various angiogenesis‐related genes in tumour‐derived endothelial cells has been investigated intensively, but there may be as yet unidentified molecules that regulate tumour angiogenesis. In the present study, the distinctive expression of regulator of G protein signalling protein 5 (RGS5) in tumour vessels in human renal cell carcinoma (RCC) has been clarified. RGS5 is a member of the RGS superfamily and acts as a negative regulator of heterotrimeric G protein‐mediated signalling through G protein‐coupled receptors (GPCRs). RT‐PCR showed strong expression of RGS5 in all RCCs examined, but expression was very weak or undetectable in normal kidneys. By real‐time RT‐PCR, the ratio of RGS5 mRNA in RCC to that in normal kidney was 6.6 : 1 (p = 0.0012). In situ hybridization showed strong expression of RGS5 in vessels within tumour cell nests. It was expressed neither in tumour cells nor in normal renal capillaries. Immunohistochemical staining using serial sections for endothelial cell markers (CD31 and CD34) and smooth muscle cell markers (α‐SMA and desmin), as well as fluorescence double staining, strongly suggested that tumour endothelial cells were the main location of RGS5 in RCC. These findings suggest that RGS5 may be involved in G protein‐mediated signalling in tumour vessels in human RCC. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Type I and III collagen protein precursors and mRNA in the developing human lung
Authors: Kaarteenaho‐Wiik Riitta , Pääkkö Paavo , Herva Riitta , Risteli Juha , Soini Ylermi
Published: April 2004

Extracellular matrix proteins have a prominent role in both ontogenesis and fibrogenesis in the human lung. The aim of this study was to analyse the expression of newly formed precursor proteins and mRNA of collagen types I and III in developing human lung tissues from 12 to 40 weeks of gestation, and also in neonatal disorders such as respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD). Lung tissues were obtained at autopsy from 60 non‐malformed cases. All tissues were analysed by immunohistochemistry and 24 were also investigated by mRNA in situ hybridization. The precursor proteins and mRNA of both collagens were expressed in abundance in pulmonary arteries and veins during all developmental periods. In RDS and BPD, precursor proteins and mRNAs of both collagen types were increased within alveolar walls. The cells in these locations showed α‐smooth muscle actin, vimentin, and variable desmin immunoreactivity. Collagen I and III precursor proteins and mRNA were also observed in pleura, bronchi, bronchioles, and around chondrocytes during all developmental periods and in diseased lung. In conclusion, collagens I and III were expressed in a similar way in and around various cell types in the developing lung and their expression was increased within alveolar walls in RDS and BPD. Myofibroblast‐type cells appeared to produce mRNA for both types of collagen in alveoli. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Remodelling of the pulmonary arteries during recovery from pulmonary hypertension induced by neonatal hypoxia
Authors: Hall Susan M , Hislop Alison A , Wu Zhongshi , Haworth Sheila G
Published: April 2004

Little is understood of the mechanisms involved in reducing pulmonary arterial wall thickness on recovery from pulmonary hypertension and the present study sought to clarify the events that occur. Piglets were exposed to hypobaric hypoxia for 3 days, either from birth or from 3 days of age, and others were exposed for 11 days starting at 3 days. All recovered in room air for up to 6 days. Using light and electron microscopy, the pulmonary artery wall thickness, the relative contribution of smooth muscle and matrix, smooth muscle cell replication, and apoptosis were assessed after hypoxic exposure and during recovery from hypoxic exposure. In elastic arteries, after 6 days' recovery in room air, a reduction in wall thickness to normal was associated with a similar reduction in proportional area of smooth muscle cells and matrix (p < 0.05), increased apoptosis (p < 0.05), and an abnormally low replication rate (p < 0.05). In peripheral muscular arteries, an increase in external diameter, and wall thinning on recovery, was achieved by smooth muscle cell remodelling and a reduction in cell replication (p < 0.05). Apoptosis did not contribute. Thus, different mechanisms are involved in recovery from hypoxia‐induced pulmonary hypertension in elastic and muscular pulmonary arteries. Recovery is slower in animals exposed from birth rather than from 3 days of age. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Properties of SEPT9 isoforms and the requirement for GTP binding
Authors: Robertson Claire , Church Stewart W , Nagar Hans A , Price John , Hall Peter A , Russell SE Hilary
Published: April 2004

Members of the evolutionarily conserved septin family of genes are emerging as key components of several cellular processes including membrane trafficking, cytokinesis, and cell‐cycle control events. SEPT9 has been shown to have a complex genomic architecture, such that up to 15 different isoforms are possible by the shuffling of five alternate amino termini and three alternate carboxy termini. Genomic and transcriptional alterations of SEPT9 have been associated with neoplasia. The present study has used a Sept9‐specific antibody to determine the pattern of isoform expression in a range of tumour cell lines. Western blot analysis indicated considerable variation in the relative amounts and isoform content of Sept9. Immunofluorescence studies showed a range of patterns of cytoplasmic localization ranging from mainly particulate to mainly filamentous. Expression constructs were also generated for each amino terminal isoform to investigate the patterns of localization of individual isoforms and the effects on cells of ectopic expression. The present study shows that the epsilon isoform appears filamentous in this overexpression system while the remaining isoforms are particulate and cytoplasmic. Transient transfection of individual constructs into tumour cell lines results in cell‐cycle perturbation with a G2/M arrest and dramatic growth suppression, which was greatest in cell lines with the lowest amounts of endogenous Sept9. Similar phenotypic observations were made with GTP‐binding mutants of all five N‐terminal variants of Sept9. However, dramatic differences were observed in the kinetics of accumulation of wild‐type versus mutant septin protein in transfected cells. In conclusion, the present study shows that the expression patterns of Sept9 protein are very varied in a panel of tumour cell lines and the functional studies are consistent with a model of septin function as a component of a molecular scaffold that contributes to diverse cellular functions. Alterations in the levels of Sept9 protein by overexpression of individual isoforms can clearly perturb cellular behaviour and may thus provide a mechanistic explanation for observations of deranged septin expression in neoplasia. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.