bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemical and enzymatic interesterification of a beef tallow and rapeseed oil equal‐weight blend
Authors: Kowalski Boleslaw , Tarnowska Katarzyna , Gruczynska Eliza , Bekas Witold
Published: October 2004

A mixture of beef tallow and rapeseed oil (1:1, wt/wt) was interesterified using sodium methoxide or immobilized lipases from Rhizomucor miehei (Lipozyme IM) and Candida antarctica (Novozym 435) as catalysts. Chemical interesterifications were carried out at 60 and 90 °C for 0.5 and 1.5 h using 0.4, 0.6 and 1.0 wt‐% CH3ONa. Enzymatic interesterifications were carried out at 60 °C for 8 h with Lipozyme IM or at 80 °C for 4 h with Novozym 435. The biocatalyst doses were kept constant (8 wt‐%), but the water content was varied from 2 to 10 wt‐%. The starting mixture and the interesterified products were separated by column chromatography into a pure triacylglycerol fraction and a nontriacylglycerol fraction, which contained free fatty acids, mono‐, and diacylglycerols. It was found that the concentration of free fatty acids and partial acylglycerols increased after interesterification. The slip melting points and solid fat contents of the triacylglycerol fractions isolated from interesterified fats were lower compared with the nonesterified blends. The sn‐2 and sn‐1,3 distribution of fatty acids in the TAG fractions before and after interesterification were determined. These distributions were random after chemical interesterification and near random when Novozym 435 was used. When Lipozyme IM was used, the fatty acid composition at the sn‐2 position remained practically unchanged, compared with the starting blend. The interesterified fats and isolated triacylglycerols had reduced oxidative stabilities, as assessed by Rancimat induction times. Addition of 0.02% BHA and BHT to the interesterified fats improved their stabilities.
Modified ferrous oxidation‐xylenol orange method to determine lipid hydroperoxides in fried snacks
Authors: Navas José A. , Tres Alba , Codony Rafael , Boatella Josep , Bou Ricard , Guardiola Francesc
Published: October 2004

A modified ferrous oxidation‐xylenol orange (FOX) method was adapted to measure lipid hydroperoxides (LHP) in lipid extracts from snack foods fried in vegetable oils. First, a methanol‐based FOX reaction medium was assayed, but this became turbid upon addition of the lipid extracts dissolved in ethanol. To avoid the precipitation of lipids, the polarity of the reaction medium was reduced by lowering its water content and by replacing the methanol as the basis of the medium for less polar solvents. Some of the solvents used instead of methanol yielded a lower FOX reaction response. Of the reaction media assayed, the one based on dichloromethane/ethanol (3:2, vol/vol) was not turbid at high lipid extract concentrations (assayed at up to 25 mg of lipid extract/mL reaction medium) and provided the same response level as the methanol‐based medium. Thus, this FOX method shows high sensitivity and is particularly useful for lipid extracts with low LHP content. This method was also successfully applied to edible oils. Solvents such as 2‐propanol, ethyl acetate and butanol were discarded, because they easily produce hydroperoxides, which interfere in the FOX reaction. Xylenol orange preparations from a number of suppliers were tested, and some differences affecting the sensitivity of the reaction were observed.
Monitoring of 2,4‐decadienal in oils and fats used for frying in restaurants in Athens, Greece
Authors: Andrikopoulos Nikolaos K. , Chiou Antonia , Mylona Anastasia , Boskou George , Dedoussis George V. Z.
Published: October 2004

Some frying by‐products of medium polarity, so‐called medium‐polarity materials (MPM), produced during domestic deep‐frying of French‐fried potatoes in edible vegetable oils, have recently been isolated and linearly correlated to % total polar materials and % polymerized triglycerides. The in vitro oxidation of low‐density lipoproteins in a dose‐dependent manner by MPM has also been reported. In the present study, the MPM constituents were identified after extraction of MPM from the oils, subsequent purification by RP‐HPLC, and GC‐MS analysis. The main constituent of MPM was trans,trans‐2,4‐decadienal, a compound that has previously been reported to be formed during peroxidation of linoleic and arachidonic acid. 2,4‐Decadienal was also quantified in oils and fats used for frying in restaurants in Athens, Greece, by direct injection of oil sample solutions in HPLC. For the most commonly used frying oils, 2,4‐decadienal concentration ranges were 0.3–119.7 mg/kg for sunflower oil, 13.3–92.7 mg/kg for cottonseed oil, 4.1–44.9 mg/kg for palm oil, and 2.0–11.3 mg/kg for vegetable cooking fats. Considering the common catering practices of frying, 2,4‐decadienal was more likely to be found in sunflower oil after deep‐frying of potatoes. Comparing the amounts of this aldehyde found in oils from restaurants to the amounts previously found for domestic frying (up to 30 mg/kg after the 8th successive frying session in sunflower oil), the probability of consuming a level of 2,4‐decadienal in restaurant‐prepared food that is higher than the level in home‐fried food was determined to be approximately one third.
Formation of hydroperoxy‐ and hydroxyalkenals during thermal oxidative degradation of sesame oil monitored by proton NMR
Authors: Guillén María D. , Ruiz Ainhoa
Published: October 2004

The usefulness of 1H nuclear magnetic resonance (NMR) for studying oil oxidation processes was tested. Refined sesame oil was submitted to oxidative conditions at 70 °C with circulating air, and the status of the sample was studied daily by 1H NMR. This technique permits the determination of the proportions of the acyl groups in the oil throughout the oxidation process and, at the same time, allows monitoring of the formation and degradation of primary oxidation compounds, as well as of the formation of secondary oxidation products. Generation of the geno‐ and cyto‐toxic oxygenated aldehydes 4‐hydroxy‐, 4‐hydroperoxy‐ and 4,5‐epoxy‐trans‐2‐alkenal was proved.
Synthesis of Gold Glyconanoparticles: Possible Probes for the Exploration of Carbohydrate‐Mediated Self‐Recognition of Marine Sponge Cells
Authors: de Souza Adriana Carvalho  , Halkes Koen M. , Meeldijk Johannes D. , Verkleij Arie J. , Vliegenthart Johannes F. G. , Kamerling Johannis P.
Published: October 2004

The first step in marine sponge cell recognition and adhesion operates via a calcium‐dependent proteoglycan− proteoglycan interaction. For the marine sponge Microciona prolifera, one of the carbohydrate epitopes involved in the proteoglycan self‐recognition is a sulfated disaccharide [GlcpNAc3S(β1−3)Fucp]. Earlier surface plasmon resonance studies have demonstrated that the proteoglycan self‐recognition can be mimicked with synthetic β‐D‐GlcpNAc‐(1→3)‐α‐L‐Fucp‐(1→O), when multivalently presented by conjugation with bovine serum albumin. Here, the straightforward synthesis of water‐soluble gold glyconanoparticles coated with the glycosides β‐D‐GlcpNAc3S‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐GlcpNAc3S‐(1→3)‐β‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐GlcpNAc3S‐(1→O)(CH2)3S(CH2)6SH, α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐Glcp‐NAc3S‐(1→3)‐α‐L‐Galp‐(1→O)(CH2)3S(CH2)6SH, β‐D‐Glcp‐NAc‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH, and β‐D‐Glcp3S‐(1→3)‐α‐L‐Fucp‐(1→O)(CH2)3S(CH2)6SH is presented. Such supramolecular structures are excellent probes for studying carbohydrate−carbohydrate interactions by transmission electron microscopy, thereby generating information on the molecular level about the role of different functionalities in the self‐recognition process. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Regioselectively N‐Functionalised 14‐Membered Azapyridinomacrocycles Bearing Trialkanoic Acid Side Chains as Ligands for Lanthanide Ions
Authors: Dioury Fabienne , Sylvestre Isabelle , Siaugue Jean‐Michel , Wintgens Véronique , Ferroud Clotilde , Favre‐Réguillon Alain , Foos Jacques , Guy Alain
Published: October 2004

Four 14‐membered azamacrocycles 2a−d, each containing a pyridine moiety and three acetic and/or propionic acid pendent arms, were prepared from regioselectively functionalised polyamines. The stability constants of the lanthanide complexes (La, Pr, Nd, Eu, Gd, Tb, Er, Yb, Lu) formed with the triacetic acid compound 2a were determined by spectroscopic methods (luminescence and/or UV/Vis spectroscopy). Other characteristics of the luminescent EuIII and TbIII complexes formed with the triacetic acid derivative 2a were also evaluated. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Alternative and Chemoselective Deprotection of the α‐Amino and Carboxy Functions ofN‐Fmoc‐Amino Acid andN‐Fmoc‐Dipeptide Methyl Esters by Modulation of the Molar Ratio in the AlCl3/N,N‐Dimethylaniline Reagent System
Authors: Di Gioia Maria Luisa , Leggio Antonella , Le Pera Adolfo , Liguori Angelo , Perri Francesca , Siciliano Carlo
Published: October 2004

The amino and carboxy functions inN‐Fmoc‐α‐amino acid andN‐Fmoc‐peptide methyl esters can be alternatively and chemoselectively deprotected by treatment with the reagent system AlCl3/N,N‐dimethylaniline (DMA). The chemoselectivity of the process is controlled by modulating the relative molar ratio of the Lewis acid and DMA. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Diastereoselective Synthesis of Thieno[3′,2′:4,5]cyclopenta[1,2‐d][1,3]oxazolines − New Ligands for the Copper‐Catalyzed Asymmetric Conjugate Addition of Diethylzinc to Enones
Authors: Bonini Bianca Flavia , Capitò Elena , Comes‐Franchini Mauro , Ricci Alfredo , Bottoni Andrea , Bernardi Fernando , Miscione Gian Pietro , Giordano Laurent , Cowley Andrew R.
Published: October 2004

Several new ligands featuring a rigid three ring skeleton have been prepared for the first time following a modular approach. Chirality has been introduced by use of an oxazoline moiety fused with a cyclopenta[b]thiophene backbone. The efficiency and stereochemical impact of these ligands on the copper‐catalyzed enantioselective addition of Et2Zn to chalcone was examined and enantiomeric excesses up to 79% were achieved using the ligand (R,R)‐16 substituted with a methyl group at the cyclopenta moiety. Computational and ESI‐mass spectral studies show that these new compounds behave as monodentate ligands towards Cu+. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Activity of Adenosine Deaminase (ADA) and Adenylate Deaminase (AMPDA) Towards 6‐Chloropurine Nucleosides Modified in the Ribose Moiety
Authors: Ciuffreda Pierangela , Buzzi Benedetta , Alessandrini Laura , Santaniello Enzo
Published: October 2004

The enzymes adenosine deaminase (ADA) and adenylate deaminase (AMPDA) are able to catalyze the hydrolytic dechlorination of 6‐chloropurine riboside and the corresponding 2′,3′‐O‐isopropylidene derivative, but show no activity towards the 3,4‐O‐isopropylidene‐1‐methylriboside of 6‐chloropurine and adenine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Solid‐State Structure and Tautomerism of 2‐Aminotroponimines Studied by X‐ray Crystallography and Multinuclear NMR Spectroscopy
Authors: Claramunt Rosa M. , Sanz Dionisia , Pérez‐Torralba Marta , Pinilla Elena , Torres M. Rosario , Elguero José
Published: October 2004

Structural studies in the solid state by X‐ray crystallography and by 13C and 15N CPMAS NMR spectroscopy carried out on a series of 2‐aminotroponimine derivatives 2−5 has allowed to establish the existence of hydrogen bonding and to determine the most stable tautomer. Almost all the structures reflect the classical double‐well potential function for the N−H···N hydrogen bonds. Only in the case of the compound N‐(pyrrol‐1‐yl)‐2‐(pyrrol‐1‐ylamino)troponimine (5) the crystal structure shows two independent molecules, one with a classical hydrogen bond and another with either a single‐well or a low‐barrier hydrogen bond. The structure of this compound is discussed with the use of the solid‐state NMR spectroscopic data. 2‐Aminotropones, as intermediates to the 2‐aminotroponimines, show the oxo‐tautomer as the stable form. B3LYP/6‐31G* calculations are used to rationalise the experimental results. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Neutral and Ionic Supramolecular Structures of Unsaturated Dicarboxylic Acids and Acridine: Significance of Molecular Geometry and Proton Transfer
Authors: Mei Xuefeng , Wolf Christian
Published: October 2004

Six supramolecular structures exhibiting distinct architectures have been prepared from acridine and different dicarboxylic acids. The co‐crystallization of acridine (1) and configurational isomers of dicarboxylic acids such as cis,trans‐muconic (a) and trans,trans‐muconic acid (b), or fumaric (c) and maleic acid (d) provided strikingly different packing motifs and properties. The supramolecular structures have been rationalized based on the molecular geometry and the constituent synthons. Co‐crystallization of acridine and b, c, or terephthalic acid (e) gave neutral assemblies stabilized by the O‐H···N hydrogen‐bond synthon I. Acridine was found to undergo proton transfer with a, d, and acetylenedicarboxylic acid (f) to form ionic supramolecular structures exhibiting synthon II, i.e. charge‐assisted carboxylate‐acridinium O−···H−N+‐hydrogen bonding. The packing mode of 1+·a− has been inferred from the corresponding acridine‐isophthalic acid analog based on the superimposable structure of the acids and the common charge‐assisted hydrogen bonding motif. Acetylenedicarboxylic and cis,trans‐muconic acid favor the formation of antiparallel acridinium π‐stacks stabilized by alternating hydrogen bonds with two infinite anionic chains of dicarboxylic acids that also undergo head‐to‐tail hydrogen bonding. Because of their different structure and geometry, b, c, d, and e form less uniform packing arrangements with 1. Fumaric and trans,trans‐muconic acid afford 2:1 neutral co‐crystals with parallel acridine rings that are stabilized by π−π‐interactions, whereas terephthalic acid favors association of antiparallel acridine dimers to adopt a different one‐dimensional network. By contrast, d undergoes intramolecular hydrogen bonding which leaves only one carboxyl group available to form a 1:1 ionic supramolecular structure with 1. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
7‐(Dimethylamino)tricyclo[5.2.2.01,6]undecene Derivatives from β‐Cyclohexenyl β‐Dimethylamino‐Substituted α,β‐Unsaturated Fischer Carbenes
Authors: Wu Yao‐Ting , Labahn Thomas , Demeter Attila , Zachariasse Klaas A. , de Meijere Armin
Published: October 2004

When heated in pyridine at 80 °C, pentacarbonyl[(2E)‐3‐cyclohexenyl‐3‐(dimethylamino)‐1‐ethoxy‐2‐propen‐1‐ylidene]chromium (1‐Cr) and ‐tungsten (1‐W) complexes undergo 6π‐electrocyclization and subsequent reductive elimination to yield the cyclohexane‐annelated cyclopentadiene 6, which equilibrates by 1,5‐hydrogen shift with its more reactive isomer 7. The latter molecule is efficiently trapped in Diels−Alder reactions with various alkynes 2 and styrenes 8 to give the cyclohexane‐annelated norbornadiene 3 and norbornene derivatives respectively, with high regio‐ and diastereoselectivity in 15−91% yields. The enol ether moiety in compound 3 is particularly easily hydrolyzed, probably due to the through‐space interaction between the two double bond moieties, so that the norbornenone derivatives 4 are isolated in all but one case after chromatographic purification. In this reaction, the tungsten complex 1‐W consistently gave lower yields than 1‐Cr. Arylalkynes with strongly electron‐withdrawing groups and minimal steric congestion are particularly suitable reaction partners for 7. The formation of bis‐cycloadducts 10 from suitable diynes largely depends upon the steric and electronic properties of the corresponding alkynyl‐substituted mono‐cycloaddition products of type 4 or 11. With the fluorenyl‐substituted tricycle 4w in acetonitrile at 25 °C, but not with 4y, dual fluorescence is observed, with a red‐shifted unstructured additional emission band with a dipole moment of 32 D, originating from intramolecular charge transfer. The molecule 2y has an exceptionally large radiative rate constant of 13 × 108 s−1. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Asymmetric Synthesis of 2‐Mono‐ and 2,3‐trans‐Disubstituted Azetidines
Authors: Enders Dieter , Gries Jörg , Kim Zin‐Sig
Published: October 2004

A versatile and efficient asymmetric synthesis of 2‐mono‐ and 2,3‐trans‐disubstituted azetidines with excellent diastereomeric (de= 93 to ⩾ 96%) and enantiomeric excesses (ee⩾ 96%) in good overall yields is described. Virtually stereoisomerically pure differentlyN,O‐protected 3‐amino‐1‐alkanols were prepared as intermediates. Key steps are a diastereoselective α‐alkylation of aldehyde SAMP‐hydrazones with benzyloxymethyl chloride as the electrophile, and a nucleophilic 1,2‐addition of various organocerium reagents to the hydrazone CN double bond. An epimerisation‐free reductive removal of the auxiliary gaveO‐benzyl‐protected 3‐amino‐1‐alkanols. AfterN‐tosylation and hydrogenolytic cleavage of the benzylic protecting group, ring closure to the correspondingN‐tosylazetidines was achieved in good yields under Mitsunobu conditions. Detosylation was easily accomplished employing sodium/naphthalene. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Convergent Syntheses of N‐Boc‐Protected (2S,4R)‐4‐(Z)‐Propenylproline and 5‐Chloro‐1‐(methoxymethoxy)pyrrol‐2‐carboxylic Acid − Two Essential Building Blocks for the Signal Metabolite Hormaomycin
Authors: Zlatopolskiy Boris D. , Kroll Hans‐Peter , Melotto Elisa , de Meijere Armin
Published: October 2004

An efficient and scalable synthesis of enantiomerically pure N‐Boc‐protected 4‐(Z)‐propenylproline (15) using the conventional Wittig reaction to construct the double bond has been developed [11% yield over 8 steps from N‐Boc‐protected (2S,4R)‐4‐hydroxyproline, 7]. The O‐MOM‐protected 5‐chloro‐1‐hydroxypyrrole‐2‐carboxylic acid [Chpca(MOM)‐OH (29)] was prepared along a reasonably efficient synthetic route applying the thermal rearrangement of 2‐azido‐6‐chloropyridine N‐oxide (22) as a key step in fairly good overall yield [9% over 7 steps from easily accessible 2,6‐dichloropyridine N‐oxide (21)]. The suitability of the MOM‐protected N‐hydroxy group during the preparation of the N‐hydroxypyrroles functionalized at C‐2, was confirmed by the successful synthesis of Chpca‐(3‐Ncp)Ala‐OFM 33 obtained from the acylated amino ester Chpca(MOM)‐(3‐Ncp)Ala‐OFM 32, which was selectively deprotected leaving the sensitive N‐hydroxypyrrole unit intact. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
The Synthesis of Ventiloquinone F and Isoventiloquinone F as Racemates
Authors: Giles Robin G. F. , Green Ivan R. , van Eeden Nestor
Published: October 2004

Racemic ventiloquinone F and isoventiloquinone F have been synthesized utilizing an initial Stobbe condensation, followed by mercury(II)‐mediated ring closure and catalytic hydrogenolysis as key steps in the synthetic protocol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Measuring the amount of statistical information in the EPT index
Authors: Kitchin Patty L.
Published: October 2004

Biological monitoring is the process of measuring the effect of environmental stress on the environment. Aquatic macroinvertebrates are widely used in the monitoring of freshwater lotic systems. The macroinvertebrate fauna of a reference stream is commonly compared to the fauna of an impacted stream that is affected by an environmental stressor. The smaller the similarity between these two streams, the greater the effect of pollution or stress on the impacted stream. Many richness measures, or statistics, exist for measuring similarity. These statistics can be computed using different levels of taxonomic resolution (species, genus and family). Many aquatic biologists believe that species‐level identifications, which require exorbitant time and expertise, are needed for correct data interpretations. The actual amount of information provided by these statistics at different taxonomic levels has never been measured. This article evaluates the amount of statistical information provided by the EPT index as compared to a sufficient statistic at the various levels of taxonomic resolution. Copyright © 2004 John Wiley & Sons, Ltd.
Testing information redundancy in environmental monitoring networks
Authors: Sarno Emma
Published: October 2004

There is a vast literature on optimal monitoring network designs. Most proposals arise from spatial statistics and they often overlook the time dimension of data collected by environmental detectors. In this work, we introduce a new concept of optimal design based on information redundancy, employing a time series approach. We model data generating processes corresponding to monitoring stations by ARIMA models and, subsequently, we measure the structural discrepancy between such models with the autoregressive distance estimator. Therefore, within a probabilistic framework we seek significant differences between models and, applying graph theory, we show how to elicit the optimal network design. Finally, a case study regarding the air monitoring network of Rome is illustrated to show how the whole procedure works in practice. Copyright © 2004 John Wiley & Sons, Ltd.
A non‐parametric 2D deformable template classifier
Authors: Schultz Nette , Nielsen Allan Aasbjerg , Conradsen Knut , Sørensen Per Settergren , Madsen Kristian Nehring
Published: October 2004

We introduce an interactive segmentation method for a sea floor survey. The method is based on a deformable template classifier and is developed to segment data from an echo sounder post‐processor called RoxAnn.

RoxAnn collects two different measures for each observation point, and in this 2D feature space the ship‐master will be able to interactively define a segmentation map, which is refined and optimized by the deformable template algorithms.

The deformable templates are defined as two‐dimensional vector‐cycles. Local random transformations are applied to the vector‐cycles, and stochastic relaxation in a Bayesian scheme is used. In the Bayesian likelihood a class density function and its estimate hereof is introduced, which is designed to separate the feature space.

The method is verified on data collected in Øresund, Scandinavia. The data come from four geographically different areas. Two areas, which are homogeneous with respect to bottom type, are used for training of the deformable template classifier, and the classifier is applied to two areas, which are heterogeneous with respect to bottom type.

The classification results are good with a correct classification percent above 94 per cent for the bottom type classes, and show that the deformable template classifier can be used for interactive on‐line sea floor segmentation of RoxAnn echo sounder data. Copyright © 2004 John Wiley & Sons, Ltd.
Rate effects on the microindentation‐based mechanical properties of oxidized, crosslinked, and highly crystalline ultrahigh‐molecular‐weight polyethylene
Authors: Gilbert Jeremy L. , Merkhan Imad
Published: October 2004

The surface micromechanical properties of ultrahigh‐molecular‐weight polyethylene (UHMWPE) are critical in determining the wear, deformation, and fracture in the surface region. These properties have not been accessible to simple mechanical testing on a spatial scale relevant to these mechanical processes until recently. The structural factors associated with surface mechanical properties (crosslinking, oxidation state, local orientation of polymer, crystallinity, etc.) can be highly variable and localized and may vary on micron spatial scales or smaller. Furthermore, time/frequency‐dependent behavior of the surface may have an important role in the overall surface mechanical behavior. Recent work has shown the utility of depth sensing microindentation/nanoindentation testing to interrogate local surface mechanical properties. The goal of the present study was to measure the effect of loading rate on the depth‐sensing microindentation testing of UHMWPE. Three different UHMWPE materials (Hylamer™, a large crystal material; GUR 1020, a standard medical‐grade material; and Marathon™, a crosslinked material) were tested using a microindentation method at loading rates ranging from 0.01 to 1 Hz. Similarly, a gamma‐irradiated in air and 15‐year shelf‐aged tibial component was tested through its cross‐section to assess the variations in mechanical properties with location and to compare the micromechanical profile with the oxidation profile. It was found that rate of testing affected the microhardness of each material, however, only GUR 1020 and Hylamer™ showed rate‐dependent behavior for modulus and energy dissipation factor. Micromechanical profiles through oxidized regions of the tibial component showed a high correlation with the oxidation profile. Increases in modulus, hardness, and energy dissipation factor were seen with increasing oxidation and each property was loading‐rate dependent. These results show that depth‐sensing microindentation/nanoindentation testing on the micron scale provides highly consistent and reproducible measurements of surface mechanical properties. This scale of testing minimizes the potential variations caused by local heterogeneity in crystallinity, surface orientation, and other submicron structural features. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 71A: 549–558, 2004
Solids modeled by ab initio crystal field methods, part 22: The Fock matrix transformed supermolecule model and the structure determination of D‐erythronic acid‐3,4‐carbonate
Authors: van Droogenbroeck Joris , Swerts Ben , Schäfer Lothar , van Alsenoy Christian
Published: October 2004

To eliminate the cutoff effects in the supermolecule model (SM), the Fock matrix transformed supermolecule model (FTSM) is developed. In this model a cyclization of the cluster is performed by means of transformations of elements of the Fock matrix, thereby restoring the translational symmetry. Besides this fundamental enhancement, significant CPU time savings are realized because, in this new procedure, not all Fock matrix elements need to be calculated. The method is applied in a study of the structure of D‐erythronic acid‐3,4‐carbonate in the crystal phase, where the new model is compared to the supermolecule model as well as the XRD experiment. The results are found to be in good agreement with experimental data. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 2065–2072, 2004
An IκB‐β COOH terminal region protein is essential for the proliferation of CHO cells under acidic stress
Authors: Lao Qizong , Kuge Osamu , Fukamachi Toshihiko , Kakegawa Tomohito , Saito Hiromi , Nishijima Masahiro , Kobayashi Hiroshi
Published: October 2004

CHO‐K1 cells were able to proliferate and maintain pHi homeostasis at pH 6.3. A novel acidic sensitive mutant, AS‐5B, which proliferated at pH 7.4 but failed to either proliferate or maintain pHi homeostasis at pH 6.3, was derived from CHO‐K1 using a replica method. The acidic‐sensitivity of AS‐5B was not due to deficiencies in sodium proton exchangers, HCO (co)transporters or H+‐ATPases. A cDNA clone encoding a COOH terminal region of IκB‐β conferred partial acidic‐resistance on AS‐5B, and the encoded protein was present in CHO‐K1, but was nearly absent from AS‐5B. Our data demonstrated that the expression of this small protein was essential for the proliferation of CHO cells under acidic stress. © 2004 Wiley‐Liss, Inc.
Identification and phenotypic characterization of a subpopulation of T84 human colon cancer cells, after selection on activated endothelial cells
Authors: Alessandro R. , Flugy A.M. , Russo D. , Stassi G. , De Leo A. , Corrado C. , Alaimo G. , De Leo G.
Published: October 2004

The extravasation of metastatic cells is regulated by molecular events involving the initial adhesion of tumor cells to the endothelium and subsequently the migration of the cells in the host connective tissue. The differences in metastatic ability could be attributed to properties intrinsic of the various primary tumor types. Thus, the clonal selection of neoplastic cells during cancer progression results in cells better equipped for survival and formation of colonies in secondary sites. A cell line (T84SF) exhibiting an altered phenotypic appearance was selected from a colon cancer cell line (T84) by repetitive plating on TNFα‐activated human endothelial cells and subsequent selection for adherent cells. Cell growth, motility, chemoinvasive abilities, tyrosine phosphorylation signaling, and the metastasis formation in nude mice of the two cell lines was compared. T84SF cells displayed in vitro an higher proliferation rate and a more invasive behavior compared to the parental cells while formed in vivo a greater number of metastatic colonies in nude mice. As concerns the signaling underlying the phenotypes of the selected cells, we examined the general tyrosine phosphorylation levels in both cell lines. Our results indicate that T84SF have an increased basal tyrosine phosphorylation of several proteins among which src kinase was identified. Treatment of cells with a specific inhibitor of src activity caused a greater in vitro inhibition of proliferation and invasive properties of T84 parental cells with respect to T84SF cells and diminished metastasis formation in vivo. Altogether, these data provide evidences that this new cell line may be valuable for identifying molecular mechanisms involved in the metastatic progression of colon cancer. © 2004 Wiley‐Liss, Inc.
Evaluation of a peptide‐based enzyme immunoassay for anti‐SARS coronavirus IgG antibody
Authors: Chan Paul K.S. , To W.K. , Liu Esther Y.M. , Ng T.K. , Tam John S. , Sung Joseph J.Y. , Lacroix Jean‐Michel , Houde Michel
Published: October 2004

High throughput assays for anti‐SARS‐CoV IgG antibody detection are need for large‐scale epidemiologic studies. The performance of a microplate enzyme immunoassay, DETECT‐SARS™, was evaluated for the detection of anti‐SARS‐CoV IgG antibody. This assay is based on synthetic peptides derived from the nucleocapsid and spike proteins. The results showed that the assay provided a high degree of sensitivity (95.9%) for convalescent serum samples. The level of specificity was close to 90%, and did not show significant variation among different control groups. The high degree of sensitivity together with the high‐throughput nature makes it advantageous as a screening assay for studies where handling of a large number of specimens is required. J. Med. Virol. 74:517–520, 2004. © 2004 Wiley‐Liss, Inc.
Prevalence of HIV‐1 non‐B subtypes, syphilis, HTLV, and hepatitis B and C viruses among immigrant sex workers in Madrid, Spain
Authors: Gutiérrez Maite , Tajada Pilar , Alvarez Amparo , De Julián Rosa , Baquero Margarita , Soriano Vincent , Holguín Africa
Published: October 2004

Sexually transmitted disease (STD) remains a major public health challenge in developed countries, exacerbated by the advent of the HIV epidemic. The objectives of this study were to assess the prevalence of serological markers of syphilis, HIV‐1/2, HTLV‐I/II, HBV, and HCV infections among immigrant sex workers in Madrid, Spain and to characterize the HIV‐1 variants in seropositive individuals. Sera from 762 immigrant commercial sex workers (75.3% from sub‐Saharan Africa, 18.2% from South America, and 6.4% from Eastern Europe) were collected between 1998 and 2003 in Madrid and examined. Antibody detection was performed by screening assays (RPR, ELISAs) and confirmed by FTA‐Abs, LIAs and Western‐blot tests. HIV‐1 subtyping was carried out by phylogenetic analyses of the protease and envelope genes. Antibodies to HIV‐1 were found in 5.2%, while 3.5% tested positive for HBsAg, 3% for syphilis antibodies, 0.8% for HCV antibodies, and 0.2% for HTLV‐I antibodies. None were reactive for HIV‐2 or HTLV‐II antibodies. HIV‐1 seroprevalence among Africans and Ecuadorians was 4.5 and 10.9%, respectively. All HIV‐1 seropositive Ecuadorians were transsexual men, and 28.6% had active syphilis infection. Up to 80% of HIV‐1 positive specimens were characterized as non‐B subtypes, with subtypes G, A, and G/A recombinants being the most frequent among African individuals. In contrast, South Americans with HIV‐1 infection carried exclusively subtype B variants. A relatively high proportion of immigrant sex workers in Madrid were infected with HIV‐1 and syphilis, whereas infections with hepatitis viruses or HTLV were uncommon. J. Med. Virol. 74:521–527, 2004. © 2004 Wiley‐Liss, Inc.
Effects of mutations in an HIV‐1 gag gene containing a 107‐codon tandem repeat in the matrix region on assembly and processing of the protein product
Authors: Liao Wei‐Hao , Chiu Hsu‐Chen , Wang Chin‐Tien
Published: October 2004

It has been demonstrated previously that a human immunodeficiency virus (HIV) type 1 Gag mutant (MA2) with a tandem repeat of 107‐matrix codons in the matrix domain could direct virus particle assembly and budding [Wang et al. (2000c): J Med Virol 61:423–432]. Since the regions involved functionally in HIV Gag assembly and transport have been mapped to the matrix domain, it was interesting to test the effects of the duplicated matrix‐coding sequence on Gag assembly, transport, and virus processing of some assembly‐defective HIV matrix mutants. In this study, a number of HIV matrix mutations were introduced into either the proximal or distal copy of the duplicated matrix‐coding sequence. Assembly, release, processing, and subcellular localization of the Gag mutants were analyzed by transient expression in 293T cells. The result indicates that the budding defect of HIV matrix mutants could be moderately or significantly reversed when the additional 107‐matrix codons were present; however, these matrix double mutations affected significantly the virus particle processing. Mislocalized matrix mutants could also be redistributed to a certain degree in the presence of the duplicated matrix copy. Although the subcellular distribution patterns of the matrix mutants did not correlate completely with the budding efficiency, the data suggest that the budding defect caused by the matrix mutations could be masked to some extent by the duplicated matrix coding sequence. J. Med. Virol. 74:528–535, 2004. © 2004 Wiley‐Liss, Inc.
Sequence variability of the α‐chemokine UL146 from clinical strains of human cytomegalovirus
Authors: Hassan‐Walker Aycan F. , Okwuadi Sylvester , Lee Lydia , Griffiths Paul D. , Emery Vincent C.
Published: October 2004

Human cytomegalovirus (HCMV) is a ubiquitous pathogen that infects a variety of cell types in vivo. A region (referred to as UL/b') present in the Toledo strain of HCMV and low passage clinical isolates contains 22 additional genes, which are absent in the highly passaged laboratory strain AD169. One of these genes, UL146, encodes an α‐chemokine. PCR amplification and sequencing of this gene from serial samples obtained from transplant recipients and samples from infants with suspected congenital HCMV infection, revealed that UL146 is a hypervariable gene in vivo. However, genetic changes were highly conserved in individuals and in renal transplant recipients multiple genotypes of UL146 were present. The majority of strains characterized maintained the conserved ELRCXC motif present in the Toledo strain of HCMV. These results provide further evidence that AD169 does not represent the authentic virus in vivo and although Towne and Toledo are more representative, major genetic differences still exist. Mixed populations of HCMV strains occur in vivo so cloning of these strains is essential if an authentic genotype is to be defined. J. Med. Virol. 74:573–579, 2004. © 2004 Wiley‐Liss, Inc.
High prevalence of mixed genotype infections in hepatitis B virus infected intravenous drug users
Authors: Chen Bing‐Fang , Chen Pei‐Jer , Jow Guey‐Mei , Sablon Erwin , Liu Chun‐Jen , Chen Ding‐Shinn , Kao Jia‐Horng
Published: October 2004

The clinical relevance of hepatitis B virus (HBV) genotypes has been documented; however, the prevalence of mixed HBV genotype infections in at‐risk groups remains controversial. The HBV genotypes were determined in 325 HBV‐infected intravenous drug users (IVDU) who were at a greater risk of multiple exposures to different HBV genotypes by using a newly developed line probe assay. The distribution of HBV genotype was as follows: genotype A alone in 2 (0.6%); genotype B alone in 256 (78.8%); genotype C alone in 10 (3.1%); mixed genotype A and B in 18 (5.5%); genotype B and C in 30 (9.2%); genotype B and D in 1 (0.3%); genotype A and C in 1 (0.3%); and mixed infections of genotype A, B, and C in 3 (0.9%). Clonal analysis confirmed further the existence of mixed genotype infection and recombination between different genotypes. Compared with our previous data, the line probe assay seemed more sensitive than polymerase chain reaction (PCR)‐restriction fragment length polymorphism (RFLP) assay in identifying HBV genotype (98.8% vs. 65.0%) and detecting mixed genotype infections (16.3% vs. 0%). In conclusion, the prevalence of mixed HBV infections is substantially higher in IVDU in endemic areas, and the line probe assay is a useful method for rapid genotyping of HBV, with particular reference to the detection of mixed genotype infections. J. Med. Virol. 74:536–542, 2004. © 2004 Wiley‐Liss, Inc.
A highly hydrophobic domain within hypervariable region 1 may be related to the entry of hepatitis C virus into cultured human hepatoma cells
Authors: Kurihara Chie , Tsuzuki Yoshikazu , Hokari Ryota , Nakashima Hiroyuki , Mataki Norikazu , Kuroki Masahiko , Kawaguchi Atsushi , Nagao Shigeaki , Kondo Toshiro , Miura Soichiro
Published: October 2004

Interaction of the envelope glycoprotein of hepatitis C virus (HCV) with a cellular receptor(s) is thought to be essential for the initial steps of HCV infection. However, the mechanisms of HCV infection remain unclear. The aim of the present study was to determine the features of HCV that enable efficient entry of the virus into human hepatocytes. Variations of hypervariable region 1 (HVR1) sequences in HCV inocula and in infected human hepatoblastoma HepG2 cells were examined. Immunofluorescence of inoculated HepG2 cells with anti‐HCV core antibodies demonstrated that HCV structural proteins were expressed in the cytoplasm, and their entry into HepG2 cells was confirmed. When the HVR1 amino acid sequences were compared, HVR1 quasispecies in the inoculated cells showed more uniformity than those of the inocula. Although there were no statistically significant differences between the two groups, hydrophobic residues were observed more frequently in the HVR1 amino acids from inoculated cells than in the HVR1 amino acids from the inocula. Results of hydropathy analysis revealed that highly hydrophobic domains exist in the middle of HVR1 in the inoculated cells in 7 of 10 patients. The results suggest that limited HCV populations are able to enter HepG2 cells and that the highly hydrophobic domain existing within the HVR1 may play an important role in the entry of HCV into cells. J. Med. Virol. 74:546–555, 2004. © 2004 Wiley‐Liss, Inc.
Complete sequence of a Kyrgyzstan swine hepatitis E virus (HEV) isolated from a piglet thought to be experimentally infected with human HEV
Authors: Lu Ling , Drobeniuc Jan , Kobylnikov Nikolay , Usmanov Rafik K. , Robertson Betty H. , Favorov Michael O. , Margolis Harold S.
Published: October 2004

Hepatitis E virus (HEV) was identified by RT‐PCR amplification with degenerate ORF2 primers in the stool of a piglet experimentally inoculated with a stool suspension from a patient with acute hepatitis during an outbreak of non‐A, non‐B hepatitis in Kyrgyzstan. Further characterization by sequencing of the complete genome and phylogenetic analysis showed that the piglet isolate was most closely related to HEV genotype 3. Because the original human stool specimen used to inoculate the piglet was no longer available, stool samples from three patients obtained during the same outbreak were sequenced and found to be HEV genotype 1. These findings suggest that the HEV isolated from the swine stool was probably an HEV enzootic in Kyrgyzstan and not the virus inoculated from the human stool. J. Med. Virol. 74:556–562, 2004. © 2004 Wiley‐Liss, Inc.
Prevalence of hepatitis E virus infection among hemodialysis patients in Japan: Evidence for infection with a genotype 3 HEV by blood transfusion
Authors: Mitsui Takehiro , Tsukamoto Yukie , Yamazaki Chikao , Masuko Kazuo , Tsuda Fumio , Takahashi Masaharu , Nishizawa Tsutomu , Okamoto Hiroaki
Published: October 2004

To investigate the prevalence of hepatitis E virus (HEV) infection among patients on maintenance hemodialysis, serum samples collected in January 2003 from 416 patients who had been undergoing hemodialysis for 7.6 ± 6.3 (mean ± standard deviation) (range, 0.3–26.0) years in a dialysis unit in Japan and serum samples that had been collected from these patients at the start of hemodialysis were tested for IgG antibodies to HEV (anti‐HEV IgG) by an “in‐house” enzyme‐linked immunosorbent assay (ELISA). Overall, 39 patients (9.4%) had anti‐HEV IgG in January 2003, and included 35 patients (8.4%) who had already been positive for anti‐HEV IgG at the start of hemodialysis and 4 patients (1%) who seroconverted after initiation of hemodialysis. Periodic serum samples that had been collected from the four seroconverted patients were tested for HEV antibodies and HEV RNA. The four patients became positive for anti‐HEV IgG in 1979, 1980, 1988, or 2003, and continued to be seropositive until the end of the observation period. Although anti‐HEV IgM was not detectable in the four patients, three were infected transiently with apparently Japanese indigenous HEV strains of genotype 3. The patient who contracted HEV infection in 1979 had been transfused with 2 U of blood 21 days before the transient viremia: one of the two stored pilot serum samples had detectable HEV RNA with 100% identity to that recovered from the patient. Our study provides evidence of transfusion‐transmitted HEV infection in Japan in 1979, and that the prevalence of de novo HEV infection during hemodialysis was low (1.1% or 4/374). J. Med. Virol. 74:563–572, 2004. © 2004 Wiley‐Liss, Inc.
Investigation of simian virus 40 large T antigen in 18 autopsied malignant mesothelioma patients in Japan
Authors: Jin Mulan , Sawa Hirofumi , Suzuki Tadaki , Shimizu Kazuko , Makino Yoshinori , Tanaka Shinya , Nojima Takayuki , Fujioka Yasunori , Asamoto Makoto , Suko Noriaki , Fujita Miri , Nagashima Kazuo
Published: October 2004

It has been reported that Simian virus 40 (SV40) is linked to human beings by inoculation of contaminated poliovaccines and may have a role in the etiology of malignant mesothelioma. However, there have been no reports describing the relationship between SV40 and malignant mesothelioma in Japan. A study was undertaken to investigate whether SV40 was related to patients of malignant mesothelioma in Japan by the polymerase chain reaction (PCR) assay, DNA sequence analysis, and immunohistochemical methods. Paraffin‐embedded samples of the 18 autopsied patients with pleural malignant mesothelioma were collected from five hospitals in Japan. After isolation of DNA from paraffin blocks, PCR analyses followed by sequencing were performed using three different sets of primers for detection of SV40 large T antigen (TAg) gene. All 18 malignant mesothelioma samples were also immunohistochemically evaluated for expression of SV40 TAg protein with two different anti‐SV40 TAg antibodies. SV40 TAg genome was detected in eight malignant mesothelioma cases. Only one of three primer pairs successfully amplified SV40 genome in the samples, whereas all pairs yielded a PCR product in the controls, suggesting a low content of virus DNA. No immunopositive staining for SV40 TAg was found in any of the samples. This study shows that SV40 genome was present in a subset of Japanese malignant mesothelioma patients who were unlikely to have received a contaminated polio vaccine based on their age. J. Med. Virol. 74:668–676, 2004. © 2004 Wiley‐Liss, Inc.
Development and evaluation of a real‐time nucleic acid sequence based amplification assay for rapid detection of influenza A
Authors: Moore Catherine , Hibbitts Sam , Owen Neil , Corden Sally A. , Harrison Graham , Fox Julie , Gelder Colin , Westmoreland Diana
Published: October 2004

The development and introduction of effective treatment for influenza A in the form of neuraminidase inhibitors have made the rapid diagnosis of infection important especially in high‐risk populations. The aim of this study was to develop a real‐time nucleic acid sequenced based amplification (NASBA) using a molecular beacon that could detect a wide range of influenza A subtypes and strains in a single reaction by targeting a conserved region of the influenza genome, and to evaluate its sensitivity and specificity against traditional laboratory techniques on a range of clinical samples usefulness during the 2003/2004 influenza season. The results demonstrated the assay to be highly sensitive and specific, detecting <0.1 TCID50 of virus stock. Three hundred eighty‐nine clinical samples were tested in total from two patient groups. Overall, the real‐time NASBA assay detected 64% (66/103) more influenza positive samples than cell culture and direct immunofluorescence (IF) and, therefore, was shown to be more sensitive in detecting influenza A in a wide range of respiratory samples than traditional methods. In conclusion, the real‐time influenza A assay demonstrated clinical usefulness in both hospital and community populations. J. Med. Virol. 74:619–628, 2004. © 2004 Wiley‐Liss, Inc.
Phylogenetic analysis of a human group B rotavirus WH‐1 detected in China in 2002
Authors: Yang Ji‐Hong , Kobayashi Nobumichi , Wang Yuan‐Hong , Zhou Xuan , Li Yan , Zhou Dun‐Jin , Hu Zhi‐Hong , Ishino Masaho , Alam Mohammed M. , Naik Trailokya N. , Ahmed Muzahed U.
Published: October 2004

A human group B rotavirus strain WH‐1 was detected in an adult sporadic case of diarrhea in Wuhan, China in 2002. In this study, the gene sequences of WH‐1 were determined in order to examine the phylogenetic relatedness to other human group B rotaviruses found previously in China (ADRV, in 1982), India (CAL‐1, in 1998), and Bangladesh (Bang373, in 2000), as well as animal viruses, and to estimate the mutation rate of group B rotavirus. VP7 (major outer capsid protein) gene of WH‐1 showed extremely high sequence identity (98.6%) to ADRV and showed relatively high sequence identities to CAL‐1 (92.5%) and Bang373 (92.4%). In contrast, identities to animal (bovine and murine) group B rotaviruses were considerably lower (61–64%). Other gene segments of WH‐1 encoding VP2, VP4, VP6, NSP1–NSP3, and NSP5 also showed high sequence identities to ADRV genes (98–99%), which were generally higher than those to CAL‐1 genes and Bang373 genes (90–95%). However, amino acid sequence identities between WH‐1 and ADRV were almost the same (VP2, VP6, and NSP3), or lower (NSP2) than those between WH‐1 and CAL‐1 (or Bang373). Since rates of synonymous substitution and transition between WH‐1 and ADRV were similar for all the segments analyzed, genetic evolution was considered to have occurred neutrally and at a similar speed in most of the RNA segments. Based on the sequence divergence between WH‐1 and ADRV, the mutation rate in natural condition of human group B rotavirus was estimated as 7.9 × 10−4 substitution/site per year. The frequency of synonymous substitution between ADRV and Bang373 was 5.7 times higher than that between ADRV and WH‐1, suggesting that the group B rotaviruses of Indian–Bangladeshi lineage diverged from that of Chinese lineage several decades ago. J. Med. Virol. 74:662–667, 2004. © 2004 Wiley‐Liss, Inc.