bluuebunny/crossref_metadata_2025 huggingface dataset:
High frequency electromagnetic fields (GSM signals) affect gene expression levels in tumor suppressor p53‐deficient embryonic stem cells
Authors: Czyz Jaroslaw , Guan Kaomei , Zeng Qinghua , Nikolova Teodora , Meister Armin , Schönborn Frank , Schuderer Jürgen , Kuster Niels , Wobus Anna M.
Published: April 2004

Effects of electromagnetic fields (EMF) simulating exposure to the Global System for Mobile Communications (GSM) signals were studied using pluripotent embryonic stem (ES) cells in vitro. Wild‐type ES cells and ES cells deficient for the tumor suppressor p53 were exposed to pulse modulated EMF at 1.71 GHz, lower end of the uplink band of GSM 1800, under standardized and controlled conditions, and transcripts of regulatory genes were analyzed during in vitro differentiation. Two dominant GSM modulation schemes (GSM‐217 and GSM‐Talk), which generate temporal changes between GSM‐Basic (active during talking phases) and GSM‐DTX (active during listening phases thus simulating a typical conversation), were applied to the cells at and below the basic safety limits for local exposures as defined for the general public by the International Commission on Nonionizing Radiation Protection (ICNIRP). GSM‐217 EMF induced a significant upregulation of mRNA levels of the heat shock protein, hsp70 of p53‐deficient ES cells differentiating in vitro, paralleled by a low and transient increase of c‐jun, c‐myc, and p21 levels in p53‐deficient, but not in wild‐type cells. No responses were observed in either cell type after EMF exposure to GSM‐Talk applied at similar slot‐averaged specific absorption rates (SAR), but at lower time‐averaged SAR values. Cardiac differentiation and cell cycle characteristics were not affected in embryonic stem and embryonic carcinoma cells after exposure to GSM‐217 EMF signals. Our data indicate that the genetic background determines cellular responses to GSM modulated EMF. Bioelectromagnetics 25:296–307, 2004. © 2004 Wiley‐Liss, Inc.
Lack of effect of 10 kV/m 60 Hz electric field exposure on pregnant dairy heifer hormones
Authors: Burchard J.F. , Nguyen D.H. , Monardes H.G. , Petitclerc D.
Published: April 2004

Sixteen pregnant Holstein heifers weighing 521 ± 46 kg, at 3.3 ± 0.7 months of gestation and 2.2 ±  2.0 months of age were confined to wooden metabolism cages and were exposed to a vertical electric field (EF) of 10.0 ± 0.4 kV/m and an artificial light cycle of 12 h light–12 h dark. The heifers were divided into two replicates of eight each. Each replicate was divided into two groups of four animals each, one group becoming the non‐exposed and the second, the EF exposed group. The exposed group were housed in metabolism cages in an area where EF were generated, and the non‐exposed group, in metabolism cages located in the adjacent area where the EF was less than 2% of that present in the exposed area. The test animals were subject to the different treatments for 4 weeks continuously. After 4 weeks, the animals switched treatment, the exposed group becoming the non‐exposed group and vice‐versa. Then the treatment continued for 4 more weeks. Catheters were inserted into the jugular vein of the animals, and blood samples were collected on twice a week to estimate the serum concentration of progesterone (P4), melatonin (MLT), prolactin (PRL), and insulin‐like growth factor‐1 (IGF‐1). Feed consumption was measured daily and feed samples were collected twice a week. The results indicated that exposure of dairy cattle to EF similar to those encountered directly underneath a 735 kV high tension electrical power line carrying a maximum load of current, cannot be associated with any variation in the experimental variables mentioned above. An exception to this, is the variation in MLT, which was associated with the EF exposure. Due to the inconsistency of the MLT response in the different replicates, caution should be exercised in the interpretation of this phenomenon. Bioelectromagnetics 25:308–312, 2004. © 2004 Wiley‐Liss, Inc.
Ion condensation and signal transduction
Authors: Ripoll Camille , Norris Vic , Thellier Michel
Published: April 2004

Many abiotic and other signals are transduced in eukaryotic cells by changes in the level of free calcium via pumps, channels and stores. We suggest here that ion condensation should also be taken into account. Calcium, like other counterions, is condensed onto linear polymers at a critical value of the charge density. Such condensation resembles a phase transition and has a topological basis in that it is promoted by linear as opposed to spherical assemblies of charges. Condensed counterions are delocalised and can diffuse in the so‐called near region along the polymers. It is generally admitted that cytoskeletal filaments, proteins colocalised with these filaments, protein filaments distinct from cytoskeletal filaments, and filamentous assemblies of other macromolecules, constitute an intracellular macromolecular network. Here we draw attention to the fact that this network has physicochemical characteristics that enable counterion condensation. We then propose a model in which the feedback relationships between the condensation/decondensation of calcium and the activation of calcium‐dependent kinases and phosphatases control the charge density of the filaments of the intracellular macromolecular network. We show how condensation might help mediate free levels of calcium both locally and globally. In this model, calcium condensation/decondensation on the macromolecular network creates coherent patterns of protein phosphorylation that integrate signals. This leads us to hypothesize that the process of ion condensation operates in signal transduction, that it can have an integrative role and that the macromolecular network serves as an integrative receptor. BioEssays 26:549–557, 2004. © 2004 Wiley Periodicals, Inc.
Can flies help humans treat neurodegenerative diseases?
Authors: Marsh J. Lawrence , Thompson Leslie Michels
Published: April 2004

Neurodegenerative diseases are becoming increasingly common as life expectancy increases. Recent years have seen tremendous progress in the identification of genes that cause these diseases. While mutations have been found and cellular processes defined that are altered in the disease state, the identification of treatments and cures has proven more elusive. The process of finding drugs and therapies to treat human diseases can be slow, expensive and frustrating. Can model organisms such as Drosophila speed the process of finding cures and treatments for human neurodegenerative diseases? We pose three questions, (1) can one mimic the essential features of human diseases in an organism like Drosophila, (2) can one cure a model organisms of human disease and (3) will these efforts accelerate the identification of useful therapies for testing in mice and ultimately humans? Here we focus on the use of Drosophila to identify potential treatments for neurodegenerative diseases such as Huntington's and we discuss how well these therapies translate into mammalian systems. BioEssays 26:485–496, 2004. © 2004 Wiley Periodicals, Inc.
Insights into the evolution of the nucleolus by an analysis of its protein domain repertoire
Authors: Staub Eike , Fiziev Petko , Rosenthal André , Hinzmann Bernd
Published: April 2004

Recently, the first investigation of nucleoli using mass spectrometry led to the identification of 271 proteins. This represents a rich resource for a comprehensive investigation of nucleolus evolution. We applied a protocol for the identification of known and novel conserved protein domains of the nucleolus, resulting in the identification of 115 known and 91 novel domain profiles. The phyletic distribution of nucleolar protein domains in a collection of complete proteomes of selected organisms from all domains of life confirms the archaebacterial origin of the core machinery for ribosome maturation and assembly, but also reveals substantial eubacterial and eukaryotic contributions to nucleolus evolution. We predict that, in different phases of nucleolus evolution, protein domains with different biochemical functions were recruited to the nucleolus. We suggest a model for the late and continous evolution of the nucleolus in early eukaryotes and argue against an endosymbiotic origin of the nucleolus and the nucleus. Supplementary material for this article can be found on the BioEssays website at http://www.interscience.wiley.com/jpages/0265‐9247/suppmat/index.html. BioEssays 26:567–581, 2004. © 2004 Wiley Periodicals, Inc.
The cadherin–catenin complex as a focal point of cell adhesion and signalling: new insights from three‐dimensional structures
Authors: Gooding Jane M. , Yap Kyoko L. , Ikura Mitsuhiko
Published: April 2004

Cadherins are a large family of single‐pass transmembrane proteins principally involved in Ca2+‐dependent homotypic cell adhesion. The cadherin molecules comprise three domains, the intracellular domain, the transmembrane domain and the extracellular domain, and form large complexes with a vast array of binding partners (including cadherin molecules of the same type in homophilic interactions and cellular protein catenins), orchestrating biologically essential extracellular and intracellular signalling processes. While current, contrasting models for classic cadherin homophilic interaction involve varying numbers of specific repeats found in the extracellular domain, the structure of the domain itself clearly remains the main determinant of cell stability and binding specificity. Through intracellular interactions, cadherin enhances its adhesive properties binding the cytoskeleton via cytoplasmic associated factors α‐ catenin, β‐catenin and p120ctn. Recent structural studies on classic cadherins and these catenin molecules have provided new insight into the essential mechanisms underlying cadherin‐mediated cell interaction and catenin‐mediated cellular signalling. Remarkable structural diversity has been observed in β‐catenin recognition of other cellular factors including APC, Tcf and ICAT, proteins that contribute to or compete with cadherin/catenin functioning. BioEssays 26:497–511, 2004. © 2004 Wiley Periodicals, Inc.
Battle of the Xs
Authors: Oliver Brian , Parisi Michael
Published: April 2004

Females and males often exhibit conspicuous morphological, physiological and behavioral differences. Similarly, gene expression profiles indicate that a large portion of the genome is sex‐differentially deployed, particularly in the germ line. Because males and females are so fundamentally different, each sex is likely to have a different optimal gene expression profile that is never fully achieved in either sex because of antagonistic selection in females versus males. Males are hemizygous for the X chromosome, which means that recessive male‐favorable de novo mutations on the X chromosome are subject to immediate selection. In females, a recessive female‐favorable mutation on one of two X chromosomes is not available for selection until it becomes frequent enough in the local population to result in homozygous individuals. Given that most mutations are recessive, one would expect that genes or alleles favoring males should accumulate on the X chromosome. Recent microarray work in Drosophila and C. elegans clearly shows the opposite. Why is the X chromosome a highly disfavored location for genes with male‐biased expression in these animals? BioEssays 26:543–548, 2004. Published 2004 Wiley Periodicals, Inc.
Prions at the crossroads: the need to identify the active TSE agent
Authors: Nandi P.K.
Published: April 2004

Structural change in the cellular prion protein, PrPC to a ProteinaseK‐resistant β‐sheet‐rich insoluble form PrPSC and its accumulation have been considered to be central to the pathogenesis of the prion diseases (TSE). In a recent paper, Deleault et al have shown that specific endogenous RNA molecules can induce in vitro structural conversion of endogenous PrPC to PrPSC.1 Small highly structured synthetic RNAs can also induce this conversion process.2 However, recent in vivo results show that PrPSC is not directly involved in the prion pathogenesis.3 It is possible, however, that nucleic‐acid‐induced PrPSC associated with the inducer nucleic acid could be the components of the infectious agent. BioEssays 26:469–473, 2004. © 2004 Wiley Periodicals, Inc.
Total Synthesis of 34‐Hydroxyasimicin and Its Photoactive Derivative for Affinity Labeling of the Mitochondrial Complex I
Authors: Han Hongna , Sinha Mantosh K. , D'Souza Lawrence J. , Keinan Ehud , Sinha Subhash C.
Published: April 2004

The asymmetric total synthesis of the 34‐hydroxyasimicin and its 3‐(4‐benzoylphenyl)propionate ester was achieved by means of a convergent synthetic strategy. This ester, which contains eight asymmetric centers, represents the first photoaffinity‐labeling agent that is derived from an Annonaceous acetogenin. The key transformations in the synthesis include the Sharpless asymmetric dihydroxylation reaction, the Wittig olefination reaction, an oxidative cyclization reaction with rhenium(vii) oxide, the Williamson etherification reaction, and a palladium‐catalyzed cross‐coupling reaction. Use of the target molecule for photoaffinity‐labeling studies of bovine mitochondrial NADH‐ubiquinone oxidoreductase (Complex I) may shed light on the structure/function of this intricate enzyme and on the origin of the high antitumor activity exhibited by the Annonaceous acetogenins.
Rational Design of the First Closed Coordination Capsule with Octahedral Outer Shape
Authors: Müller Iris M. , Spillmann Susanne , Franck Holger , Pietschnig Rudolf
Published: April 2004

The rational synthesis of an octahedral coordination capsule in which the triangular faces are covered by single ligands is described herein. Starting with tris(2‐hydroxybenzylidene)triaminoguanidinium chloride [H6L]Cl, we observed an oxidative cyclization of this ligand in the presence of PPh4+ ions resulting in the complex [Pd(H2L′)(PPh3)] (1). The use of 5,5‐diethylbarbiturate (bar2−) as a bridging ligand in the presence of [Co(en)3]3+ (en=ethylenediamine) leads to the formation of a rectangular box with the formula (Et4N)6[{Co{(PdCl)(Pd)L}2(μ‐bar)}2] (2). The analysis of the architecture of compounds 1 and 2 enables the development of a self‐assembly strategy for the synthesis of an octahedral coordination cage 3 with the formula Na4(Et3NH)12[(Pd3L)8{μ‐(bar)}12]⋅x H2O. Compound 3 was characterized by 13C‐MAS‐NMR spectroscopy and single‐crystal structure analysis.
Sterically and Guest‐Controlled Self‐Assembly of Calix[4]arene Derivatives
Authors: Shivanyuk Alexander , Saadioui Mohamed , Broda Frank , Thondorf Iris , Vysotsky Myroslav O. , Rissanen Kari , Kolehmainen Erkki , Böhmer Volker
Published: April 2004

In solvents such as chloroform or benzene, tetraurea calix[4]arenes 1 form dimeric capsules in which one solvent molecule is usually included as guest. To explore the structural requirements for the formation of such hydrogen‐bonded dimers we replaced one p‐tolylurea residue by a simple acetamide function. The resulting calix[4]arene 2 a, substituted at its wide rim with one acetamide and three p‐tolylurea functions, assumes a C1‐symmetrical conformation in apolar solvents as shown by 1H NMR, which is not compatible with the usual capsule. In the crystalline state, four molecules of 2 a, adopting a pinched cone conformation, assemble into a quasi S4‐symmetrical tetramer stabilized by a cyclic array of 24 NH⋅⋅⋅OC hydrogen bonds and four NH⋅⋅⋅π interactions. Four acetamide groups are hydrogen‐bonded to each other and pack tightly in the center of the assembly. All polar residues are buried inside the tetramer, the surface of which is lipophilic. Extensive NMR studies revealed similar structures in apolar solvents such as [D]chloroform or [D6]benzene for calixacetamides 2 a–c. The formation of these tetramers in solution is critically dependent on the size of the amide fragment, so that propionamide 2 d, butyramide 2 e, and p‐tolylamide 2 f form only ill‐defined aggregates. This is caused by steric crowding inside the tetrameric assembly. The tetramers persist during molecular dynamics simulations, and the optimized average structure of the MD run is similar to that found in the crystalline state. Theoretical studies revealed that cooperation of hydrogen bonds with multiple NH⋅⋅⋅π, CH⋅⋅⋅π, and π⋅⋅⋅π attractions make the tetramer more stable than the capsular dimer with the solvent as guest. In the presence of tetraethylammonium salts, however, compounds 2 a–e form dimeric capsular assemblies, each incorporating a single ammonium cation. Only one of two possible regioisomeric dimers is formed, in which both acetamide groups are surrounded by two urea residues. These examples give striking evidence of how self‐assembly in solution can be strongly dependent on subtle structural factors and of how the formation of dimeric capsules can be induced by the presence of an appropriate guest.
Cuprophilic Interactions in Luminescent Copper(I) Clusters with Bridging Bis(dicyclohexylphosphino)methane and Iodide Ligands: Spectroscopic and Structural Investigations
Authors: Fu Wen‐Fu , Gan Xin , Che Chi‐Ming , Cao Qian‐Yong , Zhou Zhong‐Yong , Zhu N. Nian‐Yong
Published: April 2004

Polynuclear copper(I) complexes with bridging bis(dicyclohexylphosphino)methane (dcpm) and iodide ligands, [Cu2(dcpm)2(CH3CN)2](BF4)2 (1), [Cu2(dcpm)2](BF4)2 (2), [(CuI)3(dcpm)2] (3), [(CuI)4(dcpm)2] (4), and [(CuI)2(dcpm)2] (5) were prepared and their structures determined by X‐ray crystal analysis. The shortest CuCu distance found in these complexes is 2.475(1) Å for 3. Powdered samples of 1, 3, 4, and 5 display intense and long‐lived phosphorescence with λmax at 460, 626, 590, and 456 nm and emission quantum yields of 0.26, 0.11, 0.12, and 0.56 at room temperature, respectively. In the solid state, 2 displays both a weak emission at 377 and an intense one at 474 nm with an overall emission yield 0.42. The difference in emission properties among complexes 1–5 suggests that both CuCu interaction and coordination around the copper(I) center affect the excited state properties. A degassed solution of 2 in acetone gives a bright red emission with λmax at 625 nm at room temperature. The difference absorption spectra of the triplet excited states of 1–5 in acetonitrile show broad absorption peaks at 340–410 and 850–870 nm.
Excited‐State Behavior and Photoionization of 1,8‐Acridinedione Dyes in Micelles—Comparison with NADH Oxidation
Authors: Selvaraju Chellappan , Ramamurthy Perumal
Published: April 2004

The photophysics and photochemistry of 1,8‐acridinedione dyes, which are analogues of reduced nicotinamide adenine dinucleotide (NADH), are studied in anionic and cationic micelles. Acridinedione dyes (ADDs) are solubilized in micelles at the micelle–water interface and are in equilibrium between the aqueous and micellar phase. The binding of the ADDs with micelles is attributed to hydrophobic interactions and the binding constants are determined with steady‐state and time‐resolved techniques. Nanosecond laser flash photolysis studies are carried out in aqueous, anionic, and cationic micellar solutions. The ADD undergoes photoionization in the excited state to give a solvated electron. The solvated electron reacts with the ADD to give an anion radical. In anionic micelles, the yield of the solvated electron increases because of the efficient separation of the cation radical and the electron. Cation radicals derived from the photooxidation of ADDs are involved in keto–enol tautomerization. Under acidic conditions, an enol radical cation of the acridinedione dye is formed from the keto form of the cation radical by intramolecular hydrogen atom transfer. In cationic micelles, due to electrostatic attraction, the electron cannot escape from the micelle and recombination of the cation radical and the electron results in the formation of a triplet state. For the first time, a solvated electron is observed in the laser flash photolysis of ADDs in anionic micelles. The photoionization of ADDs depends on the excitation wavelength and is biphotonic at 355 nm and monophotonic at 248 nm. From the results with this NADH model compound, the sequential electron–proton–electron transfer oxidation of NADH is confirmed and the nature of the intermediates involved in the oxidation is unraveled; these intermediates are found to depend on the pH value of the medium.
Cover Picture: Total Synthesis of 34‐Hydroxyasimicin and Its Photoactive Derivative for Affinity Labeling of the Mitochondrial Complex I (Chem. Eur. J. 9/2004)
Authors: Han Hongna , Sinha Mantosh K. , D'Souza Lawrence J. , Keinan Ehud , Sinha Subhash C.
Published: April 2004

The cover picture shows representative plants of the Annonaceae plants (background), a family of tropical trees and shrubs that accommodates over 2300 species. More than 350 acetogenins have already been isolated from 37 species in this family, many of which have shown to be potent cytotoxic, antitumor, antimalarial, immunosuppressing, pesticidal, and antifeedant agents. It has been previously proposed that the cellular target of many Annonaceous acetogenins is the mitochondrial NADH–ubiquinone oxidoreductase (Complex I). The electron microscopic three‐dimensional reconstructions of Complex I (lower right corner) from N. crassa (wire frame) and the homologous E. coli complex (surface rendered) show that the two complexes have similar structures. The cytoplasmic domain for E. coli is colored in gold and the membrane domain in blue. The surfaces of the membrane are shown schematically in red (T. Friedrich et al., Biochim. Biophys. Acta 1998, 1365, 215). All acetogenins shown in the picture were previously synthesized by the Keinan–Sinha group. The asymmetric total synthesis of 34‐acyloxy‐34‐tritio‐asimicin (bottom) was achieved by means of a convergent synthetic strategy. This photoaffinity labeling agent is designed to identify the target protein subunit in Complex I. For more details see the article by E. Keinan, S. C. Sinha et al. on p. 2149 ff.
Catalysis by Hydrotalcites and Related Materials
Authors: Tichit Didier , Coq Bernard
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Reactivity of the Acridine Ring: A Review
Authors: Chiron Julien , Galy Jean‐Pierre
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Functional Analogues of Cytochrome c Oxidase, Myoglobin, and Hemoglobin
Authors: Collman James P. , Boulatov Roman , Sunderland Christopher J. , Fu Lei
Published: April 2004

For Abstract see ChemInform Abstract in Full Text.
Fat bloom in chocolate and compound coatings
Authors: Lonchampt Pierre , Hartel Richard W.
Published: April 2004

Although bloom in chocolates and compound coatings has been studied for many decades, the specific mechanisms of fat bloom still remain largely unknown. Furthermore, it is generally considered that the mechanisms for fat bloom formation in chocolate are different than those for compound coatings.

After a brief review of chocolates and compound coatings, we summarize past studies on fat bloom formation in both products. A comparison of the effects of various parameters on bloom formation, either as accelerators or inhibitors, provides insight into the similarities and differences in these phenomena.

Based on this analysis, a global view of the mechanisms of bloom formation in both chocolates and compound coatings is suggested.
α2β1 integrin‐specific collagen‐mimetic surfaces supporting osteoblastic differentiation
Authors: Reyes Catherine D. , García Andrés J.
Published: April 2004

The interactions of osteoblasts with their surrounding extracellular matrix (ECM) are essential for skeletal development, homeostasis, and maintenance of the mature osteoblastic phenotype. Integrins are the principal transducers of ECM signals that regulate this process of osteoblast commitment and differentiation. Several studies indicate that the α2β1 integrin interaction with type I collagen is a crucial signal for the induction of osteoblastic differentiation and matrix mineralization. Integrin α2β1 recognizes the Gly‐Phe‐Hyp‐Gly‐Glu‐Arg (GFOGER) motif in residues 502–507 of the α1[I] chain of type I collagen. This study demonstrates that an α2β1 integrin‐specific GFOGER peptide triggers the activation of focal adhesion kinase and alkaline phosphatase in MC3T3‐E1 murine immature osteoblast‐like cells, two events that have been implicated in the osteoblastic differentiation pathway. These GFOGER‐peptide surfaces also support the expression of multiple osteoblast‐specific genes, including osteocalcin and bone sialoprotein, and induce matrix mineralization in a manner similar to type I collagen. This triple‐helical peptide represents a promising surface modification strategy for the design of collagen‐mimetic bioadhesive surfaces that support osteoblastic differentiation. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 69A: 591–600, 2004
Stage‐dependent modulation of limb regeneration by caffeic acid phenethyl ester (CAPE)—immunocytochemical evidence of a CAPE‐evoked delay in mesenchyme formation and limb regeneration
Authors: Brudzynski Katrina , Carlone Robert
Published: April 2004

Caffeic acid phenethyl ester (CAPE), a natural compound of bee propolis, selectively inhibits proliferation of transformed cells in several cancer models in vitro. To examine in vivo CAPE function, we used the newt regeneration blastema as a model system wherein the processes of de‐differentiation and subsequent proliferation of undifferentiated cells mimic changes associated with oncogenic transformation and tumorigenesis. We have shown that a single dose of CAPE significantly increased cell proliferation at the stages of blastema growth and re‐differentiation. At the de‐differentiation stage, CAPE significantly stimulated proliferation of wound epidermis keratinocytes, but decreased proliferation in the blastema mesenchyme. Immunohistochemistry with a mesenchymal cell marker, vimentin, revealed a highly significant reduction of vimentin staining in the mesenchyme of CAPE‐treated regenerates (p<0.001). These results, together with morphological observations indicate that, at the de‐differentiation stage, CAPE stimulated wound re‐epithelization, increased keratinocyte proliferation and increased thickness of the wound epidermis. However, CAPE inhibited mesenchyme formation and proliferation. The functional consequence of the CAPE inhibitory action was a delay in limb regeneration. J. Exp. Zool. 301A:389–400, 2004. © 2004 Wiley‐Liss, Inc.
Structure and expression of Furin mRNA in the ovary of the medaka, Oryzias latipes
Authors: Ogiwara Katsueki , Shinohara Masakazu , Takahashi Takayuki
Published: April 2004

A cDNA for furin was cloned from the ovary of the medaka, Oryzias latipes, by a combination of cDNA library screening, 5';–rapid amplification of cDNA ends (RACE), and 3'– RACE. The cDNA sequence codes for a protein of 814 amino acid residues highly homologous to other vertebrate furins, Ca2+‐dependent serine proteases belonging to the subtilysin‐like proprotein convertase family. The medaka preprofurin consists of a leader sequence, a propeptide with autoactivation sites, a Kex2–like catalytic domain, a P domain, a cysteine‐rich domain, a putative transmembrane domain, and a cytoplasmic domain. The catalytic triad residues (Asp–164, His–205, and Ser–379) were all conserved. Furin mRNA was expressed in many tissues of this, including the ovary. In the ovary, the greatest expression of furin mRNA occurred in oocytes of small growing follicles, as demonstrated by Northern blotting, RT‐PCR, and in situ hybridization analysis. Temporary and spatial expression patterns of the medaka fish furin were similar to those of stromelysin–3 and MT5–MMP during oocyte growth and postnatal development. J. Exp. Zool. 301A:449–459, 2004. © 2004 Wiley‐Liss, Inc.
Uptake of MnCl2 and mangafodipir trisodium in the myocardium: A magnetic resonance imaging study in pigs
Authors: Eriksson Rolf , Johansson Lars , Bjerner Tomas , Briley Saebo Karen , Ahlström Håkan
Published: April 2004

Purpose

To examine the changes in the longitudinal relaxation times (ΔR1) induced in pig myocardium and blood following injections of 5, 10, and 15 μmol mangafodipir trisodium (Mn‐DPDP) or MnCl2/kg of body weight (b.w.).

Materials and Methods

Twelve pigs were divided into two groups, one group receiving MnCl2 and the other receiving Mn‐DPDP. Three consecutive doses of contrast agent (5, 10, and 15 μmol/kg of b.w.) were injected in each animal with a 40‐minute time interval between each dose. Measurements of T1 in blood and myocardium were made 5, 15, 25, and 35 minutes after each injection. Additionally, relaxivity measurements in blood samples were performed.

Results

An increase in myocardial R1 was observed for both contrast agents at all concentration levels tested. This increase peaked 5 minutes after injection and then declined. An increase could still be detected 35 minutes after injection. The effect was larger when using MnCl2 than when using Mn‐DPDP.

Conclusion

The dissociation kinetics of Mn2+ from the DPDP ligand limits the relaxation increase of Mn‐DPDP relative to that of MnCl2. On the other hand, the toxicity of MnCl2 may exclude it from clinical use. J. Magn. Reson. Imaging 2004;19:564–569. © 2004 Wiley‐Liss, Inc.
Survival analysis in patients with glioblastoma multiforme: Predictive value of choline‐to‐n‐acetylaspartate index, apparent diffusion coefficient, and relative cerebral blood volume
Authors: Oh Joonmi , Henry Roland G. , Pirzkall Andrea , Lu Ying , Li Xiaojuan , Catalaa Isabelle , Chang Susan , Dillon William P. , Nelson Sarah J.
Published: April 2004

Purpose

To investigate the potential value of pre‐external‐beam radiation therapy (XRT) choline‐to‐NAA (N‐acetylaspartate) index (CNI), apparent diffusion coefficient (ADC), and relative cerebral blood volume (rCBV) for predicting survival in newly diagnosed patients with glioblastoma multiforme (GBM).

Materials and Methods

Twenty‐eight patients with GBM were studied using in vivo proton magnetic resonance spectroscopic imaging (1H MRSI) and diffusion‐ and perfusion‐weighted imaging after surgery but prior to XRT. Patients were categorized on the basis of their volumes of morphologic and metabolic abnormalities (volume of CNI ≥ 2 and CNI values), normalized ADC (nADC), or rCBV values within the T1 contrast‐enhancing and T2 regions. The median survival time was compared.

Results

A significantly shorter median survival time was observed for patients with a large volume of metabolic abnormality than for those with a small abnormality (12.0 and 17.1 months, respectively, P = 0.002). A similar pattern was observed for patients with a low mean nADC value compared to those with high mean nADC value within the T2 region (11.2 and 21.7 months, respectively, P = 0.004). A shorter median survival time was also observed for patients with contrast‐enhancing residual disease than for those without the presence of contrast enhancement with marginal significance.

Conclusion

The pre‐XRT volume of the metabolic abnormality and the nADC value within the T2 region may be valuable in predicting outcome for patients with GBM. J. Magn. Reson. Imaging 2004;19:546–554. © 2004 Wiley‐Liss, Inc.
Temperature and SAR calculations for a human head within volume and surface coils at 64 and 300 MHz
Authors: Collins Christopher M. , Liu Wanzhan , Wang Jinghua , Gruetter Rolf , Vaughan J. Thomas , Ugurbil Kamil , Smith Michael B.
Published: April 2004

Purpose

To examine relationships between specific energy absorption rate (SAR) and temperature distributions in the human head during radio frequency energy deposition in MRI.

Materials and Methods

A multi‐tissue numerical model of the head was developed that considered thermal conductivity, heat capacity, perfusion, heat of metabolism, electrical properties, and density. Calculations of SAR and the resulting temperature increase were performed for different coils at different frequencies.

Results

Because of tissue‐dependant perfusion rates and thermal conduction, there is not a good overall spatial correlation between SAR and temperature increase. When a volume coil is driven to induce a head average SAR level of either 3.0 or 3.2 W/kg, it is unlikely that a significant temperature increase in the brain will occur due to its high rate of perfusion, although limits on SAR in any 1 g of tissue in the head may be exceeded.

Conclusion

Attempts to ensure RF safety in MRI often rely on assumptions about local temperature from local SAR levels. The relationship between local SAR and local temperature is not, however, straightforward. In cases where high SAR levels are required due to pulse sequence demands, calculations of temperature may be preferable to calculations of SAR because of the more direct relationship between temperature and safety. J. Magn. Reson. Imaging 2004;19:650–656. © 2004 Wiley‐Liss, Inc.
Diaphragmatic motion in the sitting and supine positions: Healthy subject study using a vertically open magnetic resonance system
Authors: Takazakura Ryutaro , Takahashi Masashi , Nitta Norihisa , Murata Kiyoshi
Published: April 2004

Purpose

To determine the postural difference of diaphragmatic motion between the sitting and supine positions.

Materials and Methods

A total of 10 healthy men were examined using a vertically open 0.5‐T magnetic resonance (MR) system. A total of 40 sequential MR images were obtained in both the sitting and supine positions during two to five respiratory cycles. The diaphragmatic excursions (DEs) were measured on three diaphragmatic points of six sagittal planes for both positions. The differences in DEs between the anterior and posterior parts of the diaphragm were also determined.

Results

DEs in the supine position were significantly greater than those in the sitting position at 15 of the 18 points. In five of the six sagittal planes, the difference of DE between posterior and anterior points was significantly larger in the supine position than in the sitting position.

Conclusion

Diaphragmatic movement in the supine position is greater than that in the sitting position, especially in the posterior part of the diaphragm. J. Magn. Reson. Imaging 2004;19:605–609. © 2004 Wiley‐Liss, Inc.
Emotional intelligence and competitive advantage: examining the relationship from a resource‐based view
Authors: Voola Ranjit , Carlson Jamie , West Andrew
Published: April 2004

Be the change that you want to see in the world

Mahatma Gandhi (1869–1948)

Leaders have an essential role in facilitating strategic change within organizations. As resistance to change is primarily an emotional reaction to change, the study of emotions and the emotional intelligence of the leader is of growing interest in modern organizations.

From a strategic perspective, the process of how the emotional intelligence of a leader contributes to competitive advantage for an organization is unclear.

Based on the resource‐based view of the firm, this paper introduces a framework that links emotional intelligence to competitive advantage. Essentially, it is argued that emotional intelligence leads indirectly to competitive advantage by influencing the leadership capability necessary for implementing effective strategic change.

In the current volatile business environment, it is argued that organizations possessing emotionally intelligent leaders will be more likely to obtain competitive advantage. Suggestions for organizations are discussed and directions for future research are also presented.

Copyright © 2004 John Wiley & Sons, Ltd.
Squamous cell carcinoma of the anal margin
Authors: Newlin Heather E. , Zlotecki Robert A. , Morris Christopher G. , Hochwald Steven N. , Riggs Charles E. , Mendenhall William M.
Published: April 2004

Purpose

To define the optimal treatment of patients with squamous cell carcinoma (SCCA) of the anal margin.

Methods

Nineteen patients treated with curative intent by radiotherapy (RT) alone or combined with adjuvant chemotherapy (CTX) between 1979 and June 2000 were analyzed. The pertinent literature was reviewed and discussed as it related to our experience.

Results

Local control after RT or RT and CTX was observed in all 19 patients (100%). One T1 patient developed inguinal lymph node metastases and subsequently died secondary to regional and distant disease. This patient did not receive elective inguinal node RT; the lymph nodes of the other 18 patients in this analysis were irradiated. Four patients died of intercurrent disease at 25, 29, 37, and 113 months after RT, respectively. The remaining 14 patients were alive and disease‐free from 52 to 143 months after treatment. No patient suffered a severe complication or required a diverting colostomy or an abdominoperineal resection (APR) after treatment. Review of the literature reveals that the probability of cure is similar after RT alone or combined with CTX compared with surgery. Therefore, the choice of treatment depends on the anticipated functional result.

Conclusions

Patients with SCCA of the anal margin have a high likelihood of cure with sphincter preservation after RT or RT and CTX. Patients with well to moderately differentiated T1 tumors may undergo excision if it can be accomplished without compromising the sphincter. The remainder are treated with RT. Adjuvant CTX is indicated for those with T3–T4 tumors and/or involved regional nodes. J. Surg. Oncol. 2004;86:55–62. © 2004 Wiley‐Liss, Inc.
3. Acetate manufacturing, process and technology 3.1 Chemistry of cellulose acetylation
Authors: Steinmeier Hans
Published: April 2004

Nowadays Celluloseacetate is mainly produced with the acetic acid process. After an activation with acetic acid and sulfuric acid the acetylation of the cellulose starts by adding acetic anhydride. The temperature and the catalyst concentration play an important role for the reaction. Beneath acetylation also degradation of the cellulose chains occurs. In the first step of the process cellulosetriacetate is formed. In a second step, the hydrolysis, several acetyl groups are removed to achieve an average degree of substitution of 2,5. The water content in this step influences the acetyl distribution.
5.4 Properties and applications of cellulose triacetate film
Authors: Sata Hiroaki , Murayama Masahiko , Shimamoto Shu
Published: April 2004

The CTA film can be characterized by e.g. its relatively high moisture regain, significantly low birefringence, and moderate mechanical strength. Having been commercialized more than fifty years ago, it has been widely used as photographic film, protective film for polarizing plate, and optical compensation film for liquid crystal display (LCD). The photographic film application exploits the optical isotropy and unique physical properties of the CTA film. In the application of the CTA film to protective film for polarizing plate, its low in‐plane birefringence is of particular importance. In the optical compensation to enhance the viewing angle of LCD, the CTA film, because of its moderate retardation in thickness direction (Rth), serves as an element of compensator as well as a base film. Considering the growth of the LCD market, the demand for CTA film is believed to be further expanding.
5.5 Plastic materials
Authors: Carollo Paolo , Grospietro Barbara
Published: April 2004

The History of plastic CA and evolution of its markets is summarized with reference to applications. The main products (diacetate granules, and sheets) and technologies are described in terms of characteristics and flowchart. A special focus is dedicated to Diacetate sheets technologies (block process, extrusion process).
Survey on cannabis use in Parkinson's disease: Subjective improvement of motor symptoms
Authors: Venderová Kateřina , Růžička Evžen , Voříšek Viktor , Višňovský Peter
Published: April 2004

An anonymous questionnaire sent to all patients attending the Prague Movement Disorder Centre revealed that 25% of 339 respondents had taken cannabis and 45.9% of these described some form of benefit. © 2004 Movement Disorder Society
Falls and freezing of gait in Parkinson's disease: A review of two interconnected, episodic phenomena
Authors: Bloem Bastiaan R. , Hausdorff Jeffrey M. , Visser Jasper E. , Giladi Nir
Published: April 2004

Falls and freezing of gait are two “episodic” phenomena that are common in Parkinson's disease. Both symptoms are often incapacitating for affected patients, as the associated physical and psychosocial consequences have a great impact on the patients' quality of life, and survival is diminished. Furthermore, the resultant loss of independence and the treatment costs of injuries add substantially to the health care expenditures associated with Parkinson's disease. In this clinically oriented review, we summarise recent insights into falls and freezing of gait and highlight their similarities, differences, and links. Topics covered include the clinical presentation, recent ideas about the underlying pathophysiology, and the possibilities for treatment. A review of the literature and the current state‐of‐the‐art suggests that clinicians should not feel deterred by the complex nature of falls and freezing of gait; a careful clinical approach may lead to an individually tailored treatment, which can offer at least partial relief for many affected patients. © 2004 Movement Disorder Society
CSF B‐cell expansion in opsoclonus‐myoclonus syndrome: A biomarker of disease activity
Authors: Pranzatelli Michael R. , Travelstead Anna L. , Tate Elizabeth D. , Allison Tyler J. , Verhulst Steven J.
Published: April 2004

Lack of a biomarker of disease activity has hindered the therapy of childhood opsoclonus‐myoclonus syndrome (OMS), which is purported to be mediated humorally. To determine if the cerebrospinal fluid (CSF) B lymphocyte, which may traffic into the central nervous system (CNS) to produce antibody locally, is one such biomarker, B lymphocytes were immunophenotyped in the CSF and blood of 56 children with OMS and 26 pediatric controls by dual‐laser flow cytometry. Neurological severity was rated blindly from videotapes using a validated 12‐item motor evaluation scale. Children with OMS manifested a 4‐ to 7‐fold higher percentage of total B‐cells in CSF (P < 0.0001), including CD5+ (P = 0.001) and CD5− (P = 0.0004) B‐cell subsets, compared with controls, in whom the percentages were negligible and unchanging with age. CSF expansion of both B‐cell subsets increased with disease severity and decreased with disease duration (P ≤ 0.0001, ANOVA). Previous treatment with conventional immunotherapies, chemotherapy, or tumor resection had not normalized B‐cell percentages in those with lingering symptoms. These studies reveal that CSF B‐cell expansion in OMS is characteristic and often persistent. Presence of the autoreactive CD5+ B‐cell subset and correlations with neurological severity and disease duration suggest CSF B‐cell expansion is a biomarker of disease activity and possible target for B‐cell–specific therapy. Immunophenotyping of CSF lymphocytes by flow cytometry yields valuable clinical information missed by routine studies and allows crucial treatment decisions to be made rapidly. © 2004 Movement Disorder Society
Molecular characterization of the 32 kDa boar sperm protease
Authors: Pyoung Ilsun , Yi Lee S.H.
Published: April 2004

The purified 32 kDa boar sperm protease, known as the 32 kDa sperminogen, was identified by reverse transcription polymerase chain reaction (RT‐PCR) and Northern blot analysis following its partial peptide sequencing. The 32 kDa boar sperm protease was purified from the acid extracts of boar spermatozoa and subjected to CNBr‐digestion. The most prominently digested 30 kDa product was purified by HPLC and its peptide sequence was analyzed. NCBI Blast search of the analyzed 21 amino acid sequence revealed that the sequence matched 91% with that of proacrosin. DNA primer was deduced from the analyzed peptide sequence and the 32 kDa protease was further identified by RT‐PCR. Upon RT‐PCR, 1 Kbp DNA fragment was amplified, which is the expected length if the product was amplified from the proacrosin mRNA, implying that there is no separate mRNA for the 32 kDa sperminogen. To confirm these results, Northern blot analysis was performed. Four DNA probes generated from the exons of proacrosin genomic DNA sequence all detected a single species of mRNA, suggesting that there is no separate mRNA for the 32 kDa sperminogen which might be produced either from the potential separate 32 kDa sperminogen gene or by differential splicing from proacrosin mRNA. These results strongly suggest that the 32 kDa protease is part of the proacrosin/acrosin system, and that the 32 kDa sperminogen might be formed from post‐translational processing of proacrosin. Mol. Reprod. Dev. 68: 354–358, 2004. © 2004 Wiley‐Liss, Inc.
Histamine enhances cytotrophoblast invasion by inducing intracellular calcium transients through the histamine type‐1 receptor
Authors: Liu Zitao , Kilburn Brian A. , Leach Richard E. , Romero Roberto , Paria Bibhash C. , Armant D. Randall
Published: April 2004

Blastocyst implantation and placentation require molecular and cellular interactions between the uterine endometrium and blastocyst trophectoderm. Previous studies showed that histamine produced in the mouse uterine luminal epithelium interacts with trophoblast histamine type‐2 receptors (H2) to initiate blastocyst implantation. However, it is unknown whether similar histamine activity is operative in humans. Using a human cell line (HTR‐8/SVneo) derived from first‐trimester cytotrophoblasts that expresses both histamine type‐1 receptor (H1) and H2, we found that histamine promotes cytotrophoblast invasiveness specifically through activation of H1. Stimulation of H1 in human cytotrophoblasts by histamine induced intracellular Ca2+ (Ca2+i) transients by activating phospholipase C and the inositol trisphosphate pathway. The enhanced invasion induced by histamine was blocked by pretreatment with H1 antagonist or by chelation of Ca2+i. These findings suggest possible differences between rodents and humans in histamine signaling to the trophoblast. Mol. Reprod. Dev. 68: 345–353, 2004. © 2004 Wiley‐Liss, Inc.
Reduced models for fluid–structure interaction problems
Authors: Ohayon Roger
Published: April 2004

Several so‐called reduced order formulations are reviewed for linear vibration analysis of bounded fluid–structure systems for low modal density situations. Compressibility effects in the fluid for interior structural–acoustic problems, and free surface gravity effects, for hydroelastic–sloshing interaction problems in the case of incompressible liquids, are examined. Reduced order models leading to symmetric matrix systems are then described using the static well‐posed behaviour of the irrotational fluid. In this respect, the fluid–structure boundary value local equations, expressed in terms of fluid scalar field variables for the fluid (and displacement variables for the structure) are regularized for zero‐frequency limit. Copyright 2004 John Wiley & Sons, Ltd.
The modelling of multi‐fracturing solids and particulate media
Authors: Owen D. R. J. , Feng Y. T. , de Souza Neto E. A. , Cottrell M. G. , Wang F. , Andrade Pires F. M. , Yu J.
Published: April 2004

Computational strategies in the context of combined discrete/finite element methods for effective modelling of large‐scale practical problems involving multiple fracture and discrete phenomena are reviewed in the present work. The issues considered include: (1) Fracture criteria and propagation mechanisms within both the finite and discrete elements, together with mesh adaptivity procedures for discretization and introduction of fracture systems; (2) Detection procedures for monitoring contact between large numbers of discrete elements; (3) Interaction laws governing the response of contact pairs; (4) Parallel implementation; (5) Other issues, such as element methodology for near incompressible behaviour and generation of random packing of discrete objects. The applicability of the methodology developed is illustrated through selected practical examples. Copyright © 2004 John Wiley & Sons, Ltd.