bluuebunny/crossref_metadata_2025 huggingface dataset:
Distinct roles of CTLA‐4 and TGF‐β in CD4+CD25+ regulatory T cell function
Authors: Tang Qizhi , Boden Elisa K. , Henriksen Kammi J. , Bour‐Jordan Helene , Bi Mingying , Bluestone Jeffrey A.
Published: October 2004

Both CTLA‐4 and TGF‐β have been implicated in suppression by CD4+CD25+ regulatory T cells (Treg). In this study, the relationship between CTLA‐4 and TGF‐β in Treg function was examined. Blocking CTLA‐4 on wild‐type Treg abrogated their suppressive activity in vitro, whereas neutralizing TGF‐β had no effect, supporting a TGF‐β‐independent role for CTLA‐4 in Treg‐mediated suppression in vitro. In CTLA‐4‐deficient mice, Treg development and homeostasis was normal. Moreover, Treg from CTLA‐4‐deficient mice exhibited uncompromised suppressive activity in vitro. These CTLA‐4‐deficient Treg expressed increased levels of the suppressive cytokines IL‐10 and TGF‐β, and in vitro suppression mediated by CTLA‐4–/– Treg was markedly reduced by neutralizing TGF‐β, suggesting that CTLA‐4‐deficient Treg develop a compensatory suppressive mechanism through CTLA‐4‐independent production of TGF‐β. Together, these data suggest that CTLA‐4 regulates Treg function by two distinct mechanisms, one during functional development of Treg and the other during the effector phase, when the CTLA‐4 signaling pathway is required for suppression. These results help explain contradictions in the literature and support the existence of functionally distinct Treg.
Selective maturation of dendritic cells by Nippostrongylus brasiliensis‐secreted proteins drives Th2 immune responses
Authors: Balic Adam , Harcus Yvonne , Holland Martin J. , Maizels Rick M.
Published: October 2004

Helminth infections at mucosal and tissue sites strongly polarize towards Th2 immune responses, following pathways which have yet to be elucidated. We investigated whether dendritic cells (DC) exposed to gastrointestinal nematodes induce Th2 differentiation and, if so, whether this outcome reflects the absence of DC activation (the default hypothesis). We studied secreted proteins from the parasite Nippostrongylus brasiliensis, which induce Th2 development in vivo without live infection. Murine bone marrow‐derived DC pulsed with N. brasiliensis excretory/secretory antigen (NES) can, on transfer to naive recipients, prime mice for Th2 responsiveness. Heat inactivation of NES abolishes both its ability to drive Th2 responses in vivo and its capacity to stimulate DC for Th2 induction. NES, but not heat‐inactivated NES, up‐regulates DC maturation markers associated with Th2 promotion (CD86 and OX40L), with little change to CD80 and MHC class II. Moreover, DC exposed to NES readily produce IL‐6 and IL‐12p40, but not IL‐12p70. LPS induced high IL‐12p70 levels, except in DC that had been pre‐incubated with NES. These data contradict the default hypothesis, demonstrating that a helminth product (NES) actively matures DC, selectively up‐regulating CD86 and OX40L together with IL‐6 production, while blocking IL‐12p70 responsiveness in a manner consistent with Th2 generation in vivo.
Enantioselective, Potentiometric Membrane Electrodes for the Determination of L‐Pipecolic Acid in Serum
Authors: Stefan Raluca‐Ioana , Nejem R'afat Mahmoud , van Staden Jacobus Frederick , Aboul‐Enein Hassan Y.
Published: October 2004

L‐Pipecolic acid is a marker for peroxisomal disorders. Three enantioselective, potentiometric membrane electrodes were designed for the enantioanalysis of L‐pipecolic acid. These electrodes are based on carbon paste impregnated with different maltodextrins (DE: 4.0–7.0 (I), 13.0–17.0 (II) and 16.5–19.5 (III), respectively) as chiral selectors and they can be used reliably for enantiopurity assay of L‐pipecolic acid using a potentiometric method in the concentration ranges of 10−8–10−3, 10−8–10−5 and 10−10–10−6 mol/L for the maltodextrins I, II and III, respectively, based electrodes, with very low detection limits (magnitude orders of 10−9 for I and II, respectively and 10−12 mol/L for III). The proposed electrodes can be successfully applied for the enantioanalysis of L‐pipecolic acid in serum samples.
Detection of DNA and Protein Molecules Using an FET‐Type Biosensor with Gold as a Gate Metal
Authors: Shin Jang‐Kyoo , Kim Dong‐Sun , Park Hey‐Jung , Lim Geunbae
Published: October 2004

In this study, a field effect transistor (FET)‐type biosensor based on 0.5 μm standard complementary metal oxide semiconductor (CMOS) technology is proposed and its feasibility for detecting deoxyribonucleic acid (DNA) and protein molecules is investigated. Au, which has a chemical affinity with thiol by forming a self‐assembled monolayer (SAM), was used as the gate metal in order to immobilize DNA and protein molecules. A Pt pseudo‐reference electrode was employed for the detection of biomolecules. The sensor was fabricated as a p‐channel (P)MOSFET‐type because PMOSFET with positive surface potential is useful for detecting negatively charged biomolecules from the view point of its high sensitivity and fast response time. DNA and protein molecules were detected by measuring the variation of the drain current due to the variation of biomolecular charge and capacitance. DNA and protein molecules used in the experiment were 15mer–oligonucleotide probe and streptavidin‐biotin protein complexes, respectively. DNA was detected by both in situ and ex situ measurements. Additionally, to verify the interactions among SAM, streptavidin, and biotin, surface plasmon resonance (SPR) measurement was performed.
Modern sediment yield compared to geologic rates of sediment production in a semi‐arid basin, New Mexico: assessing the human impact
Authors: Gellis Allen C. , Pavich Milan J. , Bierman Paul R. , Clapp Eric M. , Ellevein Amy , Aby Scott
Published: October 2004

An Erratum has been published for this article in Earth Surface Processes and Landforms 29(13) 2004, 1707.

In the semi‐arid Arroyo Chavez basin of New Mexico, a 2·28 km2 sub‐basin of the Rio Puerco, we contrasted short‐term rates (3 years) of sediment yield measured with sediment traps and dams with long‐term, geologic rates (∼10 000 years) of sediment production measured using 10Be. Examination of erosion rates at different time‐scales provides the opportunity to contrast the human impact on erosion with background or geologic rates of sediment production. Arroyo Chavez is grazed and we were interested in whether differences in erosion rates observed at the two time‐scales are due to grazing.

The geologic rate of sediment production, 0·27 kg m−2 a−1 is similar to the modern sediment yields measured for geomorphic surfaces including colluvial slopes, gently sloping hillslopes, and the mesa top which ranged from 0·12 to 1·03 kg m−2 a−1. The differences between modern sediment yield and geologic rates of sediment production were most noticeable for the alluvial valley ﬂoor, which had modern sediment yields as high as 3·35 kg m−2 a−1. The hydraulic state of the arroyo determines whether the alluvial valley ﬂoor is aggrading or degrading. Arroyo Chavez is incised and the alluvial valley ﬂoor is gullied and piped and is a source of sediment. The alluvial valley ﬂoor is also the portion of the basin most modiﬁed by human disturbance including grazing and gas pipeline activity, both of which serve to increase erosion rates. Copyright © 2004 John Wiley & Sons, Ltd.
Comparing different methods of bed shear stress estimates in simple and complex flow fields
Authors: Biron Pascale M. , Robson Colleen , Lapointe Michel F. , Gaskin Susan J.
Published: October 2004

Bed shear stress is a fundamental variable in river studies to link ﬂow conditions to sediment transport. It is, however, difﬁcult to estimate this variable accurately, particularly in complex ﬂow ﬁelds. This study compares shear stress estimated from the log proﬁle, drag, Reynolds and turbulent kinetic energy (TKE) approaches in a laboratory ﬂume in a simple boundary layer, over plexiglas and over sand, and in a complex ﬂow ﬁeld around deﬂectors. Results show that in a simple boundary layer, the log proﬁle estimate is always the highest. Over plexiglas, the TKE estimate was the second largest with a value 30 per cent less than the log estimate. However, over sand, the TKE estimate did not show the expected increase in shear stress. In a simple boundary layer, the Reynolds shear stress seems the most appropriate method, particularly the extrapolated value at the bed obtained from a turbulent proﬁle. In a complex ﬂow ﬁeld around deﬂectors, the TKE method provided the best estimate of shear stress as it is not affected by local streamline variations and it takes into account the increased streamwise turbulent ﬂuctuations close to the deﬂectors. It is suggested that when single‐point measurements are used to estimate shear stress, the instrument should be positioned close to 0·1 of the ﬂow depth, which corresponds to the peak value height in proﬁles of Reynolds and TKE shear stress. Copyright © 2004 John Wiley & Sons, Ltd.
A laboratory study of formative conditions for characteristic ripple patterns associated with a change in wave conditions
Authors: Sekiguchi Tomohiro , Sunamura Tsuguo
Published: October 2004

A wave‐ﬂume experiment was conducted to examine the formative condition for three types of distinctive bedforms that emerged through deformation of existing ripples due to waning wave power. They were ripple marks with: (1) a single secondary crest, (2) double secondary crests, and (3) a rounded crest. Data were analysed using two parameters, kh and d0/λ*, where k is the wave number, h is the water depth, d0 is the near‐bottom orbital diameter, and λ* is the spacing of existing ripples. The former quantity, kh, was employed as a surrogate for the degree of ﬂow asymmetry. The result showed that ripples with secondary crests developed under a rather symmetrical ﬂow ﬁeld with kh ≳ 0·7, if d0/λ* ≲ 1·2, whereas rounded‐crest ripples emerged under asymmetrical ﬂow ﬁeld with kh ≲ 0·7, if d0/λ* ≲ −2·9 kh + 3·2. The number of secondary crests, which initially occurred in each trough, was single if d0/λ* ≳ 0·8, or double if d0/λ* ≲ 0·8. Copyright © 2004 John Wiley & Sons, Ltd.
Numerical taxonomic evaluation of calcium oxalate and calcium carbonate crystals in the leaves of certain Ficus species (Moraceae)
Authors: Sharawy S. M.
Published: October 2004

The type and the distribution of calcium oxalate and calcium carbonate crystals were investigated in the leaves of 33 taxa of Ficus belonging to the three subgenera Urostigma, Ficus and Sycomorus for a speculation to the inter‐subgeneric affinity. Numerical analysis of 55 characters grouped the taxa under 13 groups. The sizes of the latter with respect to the number of taxa they contain were calculated. Some resultant groups comprised taxa from different subgenera. So far as the present data are concerned and in agreement with previous workers, the var. decora of Ficus elastica and var. comosa of Ficus benjamina are better raised to the specific levels F. decora Hort and F. comosa Roxb. respectively. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Understanding and treating incompleteness in obsessive‐compulsive disorder
Authors: Summerfeldt Laura J.
Published: October 2004

Incompleteness—the troubling and irremediable sense that one's actions or experiences are not “just right”—appears to underlie many of the symptoms of obsessive‐compulsive disorder (OCD). Because incompleteness may reflect basic sensory‐affective dysfunction, it presents a challenge to clinicians wishing to apply cognitive‐behavioral treatments. In this article, I review ways of adapting well‐demonstrated treatment principles to this condition. A case is presented and then used to discuss challenges in conducting cognitive‐behavioral therapy with this population. Behavioral methods aimed at habituation (e.g., exposure and ritual prevention [ERP]) are probably more applicable than conventional cognitive techniques. However, even these may result in modest long‐term gains; relapse is a probability if they are not actively practiced after treatment cessation. © 2004 Wiley Periodicals, Inc. J Clin Psychol/In Session.
Iron specific growth inhibition of Burkitt's lymphoma cells in vitro, associated with a decrease in translocated c‐myc expression
Authors: Habel Marie‐Eve , Lemieux Réal , Jung Daniel
Published: October 2004

The cellular proto‐oncogene c‐myc is an important transcription factor that plays a role in several cellular activities such as proliferation, differentiation, and apoptosis. It follows that regulation of c‐myc expression is crucial for maintaining cell integrity. Amplification or translocation can convert this proto‐oncogene into an activated oncogene, thereby deregulating c‐myc expression. Changes in the expression of c‐myc leading to malignant cell growth and tumor progression can also be triggered by extrinsic factors. It has been reported that iron can increase cell proliferation, mainly by stimulating DNA synthesis as well as by enhancing c‐myc expression. Here, we studied the effect of iron on cells in which c‐myc expression is deregulated by either chromosomal translocation or gene amplification. When added to Burkitt's lymphoma cell lines, iron markedly inhibits cell proliferation. This effect is mediated by a cell cycle arrest in G2/M, followed by an important decrease in c‐myc expression, whereas no effect could be observed in a cell line harboring amplified c‐myc. Moreover, the down‐regulation of c‐myc expression, which is independent from cell cycle blockade, leads to cell death by apoptosis. Collectively, our results suggest the existence of a novel iron‐dependent cell cycle regulatory mechanism involving modulation of translocated c‐myc gene expression. © 2004 Wiley‐Liss, Inc.
Expression of calbindin‐D28K by yolk sac and chorioallantoic membranes of the corn snake, Elaphe guttata
Authors: Ecay Tom W. , Stewart James R. , Blackburn Daniel G.
Published: October 2004

The yolk splanchnopleure and chorioallantoic membrane of oviparous reptiles transport calcium from the yolk and eggshell to the developing embryo. Among oviparous amniotes, the mechanism of calcium mobilization to embryos has been studied only in domestic fowl, in which the mechanism of calcium transport of the yolk splanchnopleure differs from the chorioallantoic membrane. Transport of calcium is facilitated by calbindin‐D28K in endodermal cells of the yolk splanchnopleure of chickens but the chorioallantoic membrane does not express calbindin‐D28K. We used immunoblotting to assay for calbindin‐D28K expression in yolk splanchnopleure and chorioallantoic membrane of the corn snake, Elaphe guttata, to test the hypothesis that the mechanism of calcium transport by extraembryonic membranes of snakes is similar to birds. High calbindin‐D28K expression was detected in samples of yolk splanchnopleure and chorioallantoic membrane during late embryonic stages. We conclude that calbindin‐D28K is expressed in these extraembryonic membranes to facilitate transport of calcium and that the mechanism of calcium transport of the chorioallantoic membrane of the corn snake differs from that of the chicken. Further, we conclude that calbindin‐D28K expression is developmentally regulated and increases during later embryonic stages in the corn snake. J. Exp. Zool. (Mol. Dev. Evol.) 302B:000–000, 2004. © 2004 Wiley‐Liss, Inc.
Immuno‐Cross reactivity of transglutaminase and cornification marker proteins in the epidermis of vertebrates suggests common processes of soft cornification across species
Authors: Alibardi L. , Toni M.
Published: October 2004

In differentiating mammalian keratinocytes proteins are linked to the plasma membrane by epidermal transglutaminases through N‐ϵ‐(γ‐glutamyl)‐lysine isopeptide bonds to form the cornified cell envelope. The presence of transglutaminases and their protein substrates in the epidermis of nonmammalian vertebrates is not known. The present study analyses the presence and localization of the above proteins in the epidermis using immuno‐cross reactivity across different classes of amniotes. After immunoblotting, some protein bands appear labelled for loricrin, sciellin, and transglutaminase in most species. These proteins are scarce to absent in the epidermis of aquatic species (goldfish and newt) where a stratum corneum is absent or very thin. The molecular weight of transglutaminase immunoreactive bands generally varies between 40 to 62 kDa, with the most represented bands at 52–57 kDa in most species. The more intense loricrin‐ and sciellin‐immunoreactive bands are seen at 50–55–62 kDa, but are weak or absent in aquatic vertebrates. Loricrine‐like immunoreactivity is present in the epidermis where α‐(soft)‐keratinization occurs. Isopeptide bonds are mainly associated to bands in the range of 50–62 kDa. In vertebrates where hard‐keratin is expressed (the beta‐keratin corneous layer of sauropsids and in feathers) or in hair cortex of mammals, no loricrin‐like, transglutaminase‐, and isopeptide‐bond‐immunoreactivities are seen. Immunoblotting however shows loricrin‐, sciellin‐, and trasnsglutaminase‐positive bands in the corneous layers containing β‐keratin. Histologically, the epidermis of most amniotes shows variable transglutaminase immunoreactivity, but isopeptide‐bond and sciellin immunoreactivities are weak or undetactable in most species. The limitations of immunohistochemical methods are discussed and compared with results from immunoblotting. In reptilian epidermis transglutaminase is mainly localized in 0.15–0.3 µm dense granules or diffuse in transitional α‐keratogenic cells. In β‐keratogenic cells few small dense granules show a weak immunolabeling. Transglutaminase is present in nuclei of terminal differentiating α‐ and β‐keratinocytes, as in those of mature inner and outer root sheath. The present study suggests that keratinization based on loricrin, sciellin and transglutaminase was probably present in the stratum corneoum of basic amniotes in the Carboniferous. These proteins were mainly maintained in α‐keratogenic layers of amniotes but decreased in β‐keratogenic layers of sauropsids (reptiles and birds). The study suggests that similar proteins for the formation of the cornified cell envelope are present in α‐keratinocytes across vertebrates but not in β‐keratinocytes. J. Exp. Zool. (Mol. Dev. Evol.) 000: 000–000, 2004. © 2004 Wiley‐Liss, Inc.
Complete sequences of small acid‐soluble proteins from Bacillus globigii
Authors: Whiteaker Jeffrey R. , Warscheid Bettina , Pribil Partick , Hathout Yetrib , Fenselau Catherine
Published: October 2004

Three abundant small acid‐soluble proteins (SASPs) from spores of Bacillus globigii were sequenced using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry with post‐source decay and nanoelectrospray collision‐induced dissociation tandem mass spectrometry. The proteins were extracted from spores with 1 M HCl. Scanning electron micrographs of spores before and after acid extraction show that the spores retain their overall structure but have a shriveled texture following the acid treatment. Extracted SASPs were purified by high‐performance liquid chromatography and molecular masses of the SASPs were identified at 7068 (SASP‐1), 7332 (SASP‐2), and 8889 (γ‐SASP). De novo peptide sequencing was used to determine the protein sequences. The correct ordering of peptide sequences was aided by mapping overlapping enzymatic digests and by comparison with homologous SASPs from Bacillus stearothermophilus. B. globigii is used in many field tests as a surrogate for B. anthracis. Thus complete SASP sequences from B. globigii will facilitate the development of methods for rapid identification of bacteria based on mass spectrometry and the examination of taxonomic relationships between Bacillus species. Copyright © 2004 John Wiley & Sons, Ltd.
Liquid chromatography/tandem mass spectrometry of unusual phenols from Yucca schidigera bark: comparison with other analytical techniques
Authors: Montoro Paola , Piacente Sonia , Oleszek Wieslaw , Pizza Cosimo
Published: October 2004

Qualitative and quantitative analyses of phenolic compounds are of interest for both medicinal and food plants. In the present work, the phenolic fraction from Yucca schidigera, a plant bearing the GRAS (Generally Recognized as Safe) label approved by the US Food and Drug Administration, was studied. Crude extracts of Y. schidigera bark were investigated by liquid chromatography/UV spectrophotometry with diode‐array detection, liquid chromatography/electrospray ionization mass spectrometry (LC/ESI‐MS) and liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS), in order to develop and optimize simple and rapid techniques to determine both stilbenes and yuccaols for the purposes of quality control of collected material. With optimal LC and MS conditions, stilbenes and yuccaols were quantified with all the proposed methods and the results were compared. Sensitivity was evaluated and the results indicated that MS/MS detection in the multiple reaction monitoring mode is easily applicable to this plant and allows the rapid and direct identification and quantification of these peculiar compounds in crude plant extracts. Copyright © 2004 John Wiley & Sons, Ltd.
Laccase‐catalyzed mediated oxidation of benzyl alcohol: the role of TEMPO and formation of products including benzonitrile studied by nanoelectrospray ionization Fourier transform ion cyclotron resonance mass spectrometry
Authors: Marjasvaara Asse , Torvinen Mika , Vainiotalo Pirjo
Published: October 2004

Substituted benzyl alcohol was oxidized enzymatically with a laccase–mediator system and the products were investigated as a function of time by nanoelectrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (nanoESI‐FTICRMS). With Trametes versicolor laccase (TVL), the mediator, 2,2′,6,6′‐tetramethylpiperidine‐N‐oxyl radical (TEMPO), undergoes oxidation and forms oxoammonium ion. Oxidized TEMPO oxidizes the alcohol and is simultaneously reduced to the NOH form. The laccase then restores TEMPO back to the normal radical form and the oxidation cycle starts again. The role of TEMPO and the structures of its oxidized and reduced forms in the enzymatic oxidation process were clarified in collision‐induced dissociation experiments and gas‐phase hydrogen/deuterium (H/D) exchange reactions. The amounts of enzyme and mediator were significant for product formation: with greater amounts overoxidation products, the corresponding benzoic acid and benzonitrile were formed. Smaller amounts of laccase and mediator generated benzaldehyde in high yield. The reaction pathway for benzonitrile formation is discussed and it is suggested to start from benzaldehyde and the ammonia in the ammonium acetate buffer. Copyright © 2004 John Wiley & Sons, Ltd.
Determination of paraquat and diquat in human body fluids by high‐performance liquid chromatography/tandem mass spectrometry
Authors: Lee Xiao‐Pen , Kumazawa Takeshi , Fujishiro Masaya , Hasegawa Chika , Arinobu Tetsuya , Seno Hiroshi , Ishii Akira , Sato Keizo
Published: October 2004

Paraquat (PQ) and diquat (DQ) in human whole blood and urine were analyzed by high‐performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS) with positive ion electrospray ionization (ESI). The compounds were extracted with Sep‐Pak C18 cartridges from whole blood and urine samples containing ethyl paraquat as an internal standard. The separation of PQ and DQ was carried out using ion‐pair chromatography with heptafluorobutyric acid in 20 mM ammonium acetate and acetonitrile gradient elution for successful coupling with MS. Both compounds formed base peaks due to [M  H]+ ions by HPLC/ESI‐MS and the product ions produced from each [M  H]+ ion by HPLC/MS/MS. Selective reaction monitoring (SRM) showed much higher sensitivity for both body fluids. Therefore, a detailed procedure for the detection of compounds by SRM with HPLC/MS/MS was established and carefully validated. The recoveries of PQ and DQ were 80.8–95.4% for whole blood and 84.2–96.7% for urine. The calibration curves for PQ and DQ showed excellent linearity in the range of 25–400 ng ml−1 of whole blood and urine. The detection limits were 10 ng ml−1 for PQ and 5 ng ml−1 for DQ in both body fluids. The intra‐ and inter‐day precision for both compounds in whole blood and urine samples were not greater than 13.0%. The data obtained from the determination of PQ and DQ in rat blood after oral administration of the compounds are also presented. Copyright © 2004 John Wiley & Sons, Ltd.
Electrospray mass and tandem mass spectrometry of homologous and isomeric singly, doubly, triply and quadruply charged cationic ruthenated meso‐(phenyl)m‐(meta‐ and para‐pyridyl)n (m + n = 4) macrocyclic porphyrin complexes
Authors: Tomazela Daniela M. , Gozzo Fabio C. , Mayer Ildemar , Engelmann Fábio M. , Araki Koiti , Toma Henrique E. , Eberlin Marcos N.
Published: October 2004

Ten homologous or isomeric singly, doubly, triply and quadruply charged cationic macrocyclic complexes I–Va, bn+ (n = 1–4) formed by the coordination of [Ru(bipy)2Cl]+ to the pyridyl N‐atoms of a series of meso‐(phenyl)m‐(meta or para‐pyridyl)n‐porphyrins (m + n = 4) were transferred to the gas phase and structurally characterized by electrospray ionization (ESI) mass (MS) and tandem mass (MS/MS) spectrometry. Previously known to be stable in solution and in the solid state, I–Va, bn+ are found to constitute also a new class of stable, long‐lived multiply charged gas‐phase ions with spatially separated charge sites. Increasing intramolecular electrostatic repulsion from Ia, b+ to IVa, b3+ facilitates in‐source and tandem collision‐induced dissociation (CID). However, for the quadruply charged ions Va, b4+, electrostatic repulsion is alleviated mainly by ion pairing with the CF3SO3− counterion forming the salt clusters [Va,b/CF3SO3]3+ and [Va,b/(CF3SO3)2]2+ with reduced charge states. Ion‐pairing that yields [IVa,b/CF3SO3]2+ is also observed as a minor ESI process for the triply charged ions IVa, b3+. The gaseous ions I–Va, bn+ (n = 2, 3 or 4) dissociate by sequential ‘charge partitioning’ with the formation of two cationic fragments by the release of [Ru(bipy)2Cl]+. The meta (a) and para (b) isomers and the positional isomers II2+ and III2+ display nearly identical ESI‐MS and ESI‐MS/MS spectra. ESI‐MS/MS of I–Va, bn+ shows that the Rupy(P) is, intrinsically, the weakest bond since this bond breaks preferentially upon CID. Copyright © 2004 John Wiley & Sons, Ltd.
Matrix‐free infrared soft laser desorption/ionization
Authors: Rousell David J. , Dutta Sucharita M. , Little Mark W. , Murray Kermit K.
Published: October 2004

Infrared soft laser desorption/ionization was performed using a 2.94 µm Er : YAG laser and a commercial reflectron time‐of‐flight mass spectrometer. The instrument was modified so that a 337 nm nitrogen laser could be used concurrently with the IR laser to interrogate samples. Matrix‐assisted laser desorption/ionization (MALDI), laser desorption/ionization and desorption/ionization on silicon with UV and IR lasers were compared. Various target materials were tested for IR soft desorption ionization, including stainless steel, aluminum, copper, silicon, porous silicon and polyethylene. Silicon surfaces gave the best performance in terms of signal level and low‐mass interference. The internal energy resultant of the desorption/ionization was assessed using the easily fragmented vitamin B12 molecule. IR ionization produced more analyte fragmentation than UV‐MALDI analysis. Fragmentation from matrix‐free IR desorption from silicon was comparable to that from IR‐MALDI. The results are interpreted as soft laser desorption and ionization resulting from the absorption of the IR laser energy by the analyte and associated solvent molecules. Copyright © 2004 John Wiley & Sons, Ltd.
Off‐line capillary electrophoresis/fully automated nanoelectrospray chip quadrupole time‐of‐flight mass spectrometry and tandem mass spectrometry for glycoconjugate analysis
Authors: Bindila Laura , Almeida Reinaldo , Sterling Alistair , Allen Mark , Peter‐Katalinić Jasna , Zamfir Alina
Published: October 2004

Implementation and optimization of an off‐line capillary electrophoresis (CE)/(−)nanoESIchip‐quadrupole time‐of‐flight (QTOF) mass spectrometric (MS) and tandem MS system for compositional mapping and structural investigation of components in complex carbohydrate mixtures is described. The approach was developed for glycoscreening and applied to O‐glycosylated peptides from urine of a patient suffering from α‐N‐acetylhexosaminidase deficiency, known as Schindler's disease. The fundamental issue of sensitivity, previously representing a serious drawback of the off‐line CE/MS analysis, could be positively addressed by the off‐line conjunction of CE with automated chip‐based ESI‐QTOF‐MS to provide flexibility for CE/chip MS coupling and enhance structural elucidation of single components in heterogeneous mixtures. Copyright © 2004 John Wiley & Sons, Ltd.
Is the social entrepreneur a new type of leader?
Authors: Barendsen Lynn , Gardner Howard
Published: October 2004

An in‐depth look at innovative change agents.
Courage to lead: A call to action
Authors: Hesselbein Frances
Published: October 2004

Courageous leaders are healers and unifiers.
Practicing servant‐leadership
Authors: Spears Larry C.
Published: October 2004

The growing impact of the servant‐leadership revolution.
Rethinking innovation
Authors: Markides Constantinos
Published: October 2004

A new strategy for mature businesses in pursuing radical innovation.
Ternary Conjugates as a Result of Exchange Reactions Between Polyelectrolyte Complexes and Surfactants: Formation and Stability
Authors: Zintchenko Arkadi , Koňák Čestmir
Published: October 2004

Summary: The exchange of sodium polymethacrylate (Na‐PMA) for anionic surfactant sodium dodecylsulfate (SDS) in a polyelectrolyte complex of Na‐PMA and poly(L‐lysine) (PLL) was studied by light scattering techniques. The exchange reaction proceeds inside the complex particles without any aggregation. It causes swelling of the particles and the formation of thick polymer shell around them. In order to prove the formation of the shell, the colloidal stability of the particles in salt solutions was studied. The addition of SDS to a complex solution dramatically increases colloid stability. The stability was found to be independent of the mixing ratio of the initial complex, depending only on the molecular weight of Na‐PMA and slowly decreasing with time. The mechanism of the exchange reaction was proposed. The addition of SDS causes fast substitution of charged units of Na‐PMA for surfactant molecules in the complex and formation of the PLL/SDS complex stabilized by hydrophobic interactions between aliphatic chains of SDS. The Na‐PMA chains cannot be released sufficiently fast from the particles due to entanglements of the chains inside the particles. They build a thick stabilizing shell around the particles and lead to their swelling. This shell protects the particles against coagulation at relatively high salt concentrations. However, such state of the particles does not correspond to thermodynamic equilibrium. Na‐PMA is very slowly released from the particles, decreasing the density of stabilizing shell and stability of the particles in salt solutions. The possible application of ternary conjugates in drug delivery is discussed.

Schematic representation of changes in structure and stability of Na‐PMA/PLL complex particles upon the exchange of polyanion Na‐PMA for negatively charged surfactant SDS.

magnified image

Schematic representation of changes in structure and stability of Na‐PMA/PLL complex particles upon the exchange of polyanion Na‐PMA for negatively charged surfactant SDS.
Compactness under constructive scrutiny
Authors: Ishihara Hajime , Schuster Peter
Published: October 2004

How are the various classically equivalent definitions of compactness for metric spaces constructively interrelated? This question is addressed with Bishop‐style constructive mathematics as the basic system – that is, the underlying logic is the intuitionistic one enriched with the principle of dependent choices. Besides surveying today's knowledge, the consequences and equivalents of several sequential notions of compactness are investigated. For instance, we establish the perhaps unexpected constructive implication that every sequentially compact separable metric space is totally bounded. As a by‐product, the fan theorem for detachable bars of the complete binary fan proves to be necessary for the unit interval possessing the Heine‐Borel property for coverings by countably many possibly empty open balls. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the complexity of finding paths in a two‐dimensional domain I: Shortest paths
Authors: Chou Arthur W. , Ko Ker‐I
Published: October 2004

The computational complexity of finding a shortest path in a two‐dimensional domain is studied in the Turing machine‐based computational model and in the discrete complexity theory. This problem is studied with respect to two formulations of polynomial‐time computable two‐dimensional domains: (A) domains with polynomialtime computable boundaries, and (B) polynomial‐time recognizable domains with polynomial‐time computable distance functions. It is proved that the shortest path problem has the polynomial‐space upper bound for domains of both type (A) and type (B); and it has a polynomial‐space lower bound for the domains of type (B), and has a #P lower bound for the domains of type (A). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Functional interpretation and the existence property
Authors: Frovin Jørgensen Klaus
Published: October 2004

It is shown that functional interpretation can be used to show the existence property of intuitionistic number theory. On the basis of truth variants a comparison is then made between realisability and functional interpretation showing a structural difference between the two. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Herbrandizing search problems in Bounded Arithmetic
Authors: Hanika Jiří
Published: October 2004

We study search problems and reducibilities between them with known or potential relevance to bounded arithmetic theories. Our primary objective is to understand the sets of low complexity consequences (esp. Σb1or Σb2) of theories Si2and Ti2for a smalli, ideally in a rather strong sense of characterization; or, at least, in the standard sense of axiomatization. We also strive for maximum combinatorial simplicity of the characterizations and axiomatizations, eventually sufficient to prove conjectured separation results. To this end two techniques based on the Herbrand's theorem are developed. They characterize/axiomatize Σb1‐consequences of Σb2‐definable search problems, while the method based on the more involved concept of characterization is easier and gives more transparent results. This method yields new proofs of Buss' witnessing theorem and of the relation between PLS and Σb1(T12), and also an axiomatization of Σb1(T22). (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
There is no low maximal d. c. e. degree – Corrigendum
Authors: Arslanov Marat , Cooper S. Barry , Li Angsheng
Published: October 2004

We give a corrected proof of an extension of the Robinson Splitting Theorem for the d. c. e. degrees. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Recombinant tropomyosin from Penaeus aztecus (rPen a 1) for measurement of specific immuno‐ globulin E antibodies relevant in food allergy to crustaceans and other invertebrates
Authors: DeWitt Åsa Marknell , Mattsson Lars , Lauer Iris , Reese Gerald , Lidholm Jonas
Published: October 2004

Immunoglobulin E (IgE)‐mediated food allergy to crustaceans and mollusks is relatively common and affected individuals typically react to a range of different species. The only known major allergen of shrimp was first described over 20 years ago and later identified as the muscle protein tropomyosin. This protein may be useful as a defined and relevant diagnostic marker for allergic sensitization to invertebrate foods. In order to generate an assay reagent suitable for this purpose, tropomyosin from the shrimp Penaeus aztecus (Pen a 1) was produced as a recombinant protein in Escherichia coli and characterized with respect to IgE antibody binding properties in comparison to natural shrimp tropomyosin. Hexahistidine‐tagged rPen a 1 accumulated as a predominantly soluble protein in the E. coli expression host and a two‐step chromatographic procedure provided a high yield of pure and homogeneous protein. rPen a 1 displayed chromatographic and folding characteristics similar to those of purified natural shrimp tropomyosin. Serum preincubation with serial protein dilutions revealed similar capacity of recombinant and natural tropomyosin to compete with immobilized shrimp extract for IgE binding. rPen a 1 was further shown to extensively and specifically compete for IgE binding to extracts of other crustacean species, house dust mite and German cockroach.
Immunoglobulin E‐reactivity of wheat‐allergic subjects (baker's asthma, food allergy, wheat‐dependent, exercise‐induced anaphylaxis) to wheat protein fractions with different solubility and digestibility
Authors: Mittag Diana , Niggemann Bodo , Sander Ingrid , Reese Imke , Fiedler Eva‐Maria , Worm Margitta , Vieths Stefan , Reese Gerald
Published: October 2004

Baker's asthma, food allergy to wheat, and wheat‐dependent, exercise‐induced anaphylaxis (WDEIA) are different clinical forms of wheat allergy. We investigated the correlation of solubility and digestion stability of wheat allergens with the IgE‐reactivity patterns of different patient groups. Three wheat protein fractions were extracted according to their solubility: salt‐soluble albumins and globulins, ethanol‐soluble gliadins, and glutenins soluble only after treatment with detergents and reducing reagents. Sera from subjects with history of each variant of wheat allergy were characterized by CAP FEIA and immunoblotting. There was a high degree of heterogeneity of recognized allergens between the different subject groups as well as within these groups. However, subjects with WDEIA showed similar immunoglobulin E (IgE)‐reactivity patterns to gliadins and especially to a 65 kDa protein. Subjects with baker's asthma as well as the food‐allergic subjects had the most intense IgE‐reactivity to the albumin/globulin fraction. The latter group additionally showed IgE‐reactivity to the other fractions. Divergent results of immunoblotting and CAP‐FEIA demonstrated that the detection of wheat‐specific IgE highly depends on the applied method, thus the diagnostic tool must be carefully chosen. Most wheat allergens were rapidly digested as analyzed by determination of IgE‐reactivity on immunoblots to wheat extracts after simulation of gastric and duodenal digestion. However, ethanol‐soluble gliadins were stable to gastric enzymes and exhibit low solubility in gastric and duodenal fluids. Therefore, they are likely to be important in food allergy to wheat.
Allergy assessment of foods or ingredients derived from biotechnology, gene‐modified organisms, or novel foods
Authors: Poulsen Lars K.
Published: October 2004

The introduction of novel proteins into foods carries a risk of eliciting allergic reactions in individuals sensitive to the introduced protein and a risk of sensitizing susceptible individuals. No single predictive test exists to perform a hazard assessment in relation to allergenic properties of newly expressed proteins in gene‐modified organisms (GMOs). Instead, performance of a weighted risk analysis based on the decision tree approach has been suggested. The individual steps of this analysis comprise sequence homology to known allergens, specific or targeted serum screens for immunoglobulin E (IgE) cross‐reactions to known allergens, digestability studies of the proteins in simulated gastric and/or intestinal fluids, and animal studies. These steps are discussed and five examples of risk evaluation of GMOs or novel foods are presented. These include ice‐structuring protein derived from fish, microbial transglutaminase, GMO‐soybeans, amylase and the Nangai nut.
Preconditioning strategies for non‐Hermitian Toeplitz linear systems
Authors: Huckle Thomas , Serra‐Capizzano Stefano , Tablino‐Possio Cristina
Published: October 2004

In this paper, we propose and analyse preconditioning strategies for non‐Hermitian Toeplitz linear systems. These techniques used in connection with the GMRES algorithm allow to solve in an optimal way the corresponding linear systems. Copyright © 2004 John Wiley & Sons, Ltd.
Asymptotic relationships between singular values of structured matrices similarly generated by different formal expansions of a rational function
Authors: Trench W. F.
Published: October 2004

We define a class of formal expansions ∑ α𝓁z𝓁 of a rational function with at least one non‐zero pole. To distinct formal expansions ∑ α𝓁z𝓁 and ∑ β𝓁z𝓁 in this class we associate structured arrays A=(aij) and B =(bij), defined by aij=∑avα and bij=∑avβ, where q(≠0), p1,…,pk, and τ1,…,τk are integers and a1,…,ak are non‐zero complex constants. We study the asymptotic relationship between the singular values of the matrices (aij) and (bij) as min(hn, kn)→∞. Copyright © 2004 John Wiley & Sons, Ltd.
Symmetric schemes and Hamiltonian perturbations of linear Hamiltonian problems
Authors: Amodio P. , Iavernaro F. , Trigiante D.
Published: October 2004

We analyse the behaviour of symmetric boundary value methods applied to Hamiltonian evolutionary problems. We derive a forward–backward error analysis which allows us to state that the obtained numerical solution may be essentially regarded as the exact solution of a perturbed Hamiltonian problem of the same type as the original one and vice versa. A numerical test emphasizes the theoretical results. Copyright © 2004 John Wiley & Sons, Ltd.
Newton iterations for a non‐symmetric algebraic Riccati equation
Authors: Lu Lin‐Zhang
Published: October 2004

The computation of the minimal positive solution of a non‐symmetric algebraic Riccati equation arising in transport theory is considered. It was shown in (SIAM J Matrix Anal Appl, submitted) that this can be done via only computing the minimal positive solution of a vector equation, which is derived from special form of the solutions of the Riccati equation and by exploitation of the special structure of the coefficient matrices of the Riccati equation. In this paper, the Newton method is developed for the vector equation. The Newton method is more simple and efficient than the corresponding Newton method directly for original Riccati equation and can preserve the form that any solution of the Riccati equation must satisfy. Combination of the simple iteration and the Newton iteration is also considered. Numerical examples are given. Copyright © 2004 John Wiley & Sons, Ltd.
Fast regularized structured total least squares algorithm for solving the basic deconvolution problem
Authors: Mastronardi N. , Lemmerling P. , Van Huffel S.
Published: October 2004

In this paper, we develop a fast regularized structured total least squares (RSTLS) algorithm for solving the basic deconvolution problem. The algorithm is based on a particular implementation of the generalized Schur algorithm. We apply the new algorithm on a deconvolution problem arising in a medical application in renography. By means of this example, we show that regularization in the structured total least squares framework yields more accurate results compared to other estimators. Copyright © 2004 John Wiley & Sons, Ltd.
Myositis complicating viridans streptococcal sepsis in childhood leukemia
Authors: Sandlund John T. , Howard Scott C. , Hijiya Nobuko , Pui Ching‐Hon , Shenep Jerry L. , Adderson Elisabeth E.
Published: October 2004

Hematogenous focal infections are a rare complication of bacteremia or sepsis caused by viridans‐group streptococci. We describe two patients with acute leukemia who developed myositis during α‐hemolytic streptococcal bacteremia. Children complaining of severe muscle pain associated with viridans streptococcal infections should be carefully evaluated for the presence of focal pyogenic complications and rhabdomyolysis. The severity of infectious myositis is highly variable, depending on the etiologic organism and host immunity, making individualized treatment the most effective approach. © 2004 Wiley‐Liss, Inc.
Identification of patients with Churg–Strauss syndrome (CSS) using automated data
Authors: Harrold Leslie R. , Andrade Susan E. , Eisner Mark , Buist A. Sonia , Go Alan , Vollmer William M. , Chan K. Arnold , Frazier E. Ann , Weller Peter F. , Wechsler Michael E. , Davis Kourtney J. , Platt Richard
Published: October 2004

Purpose

Our aim was to identify individuals with Churg–Strauss syndrome (CSS) among asthma drug users, based on patterns of diagnostic and procedural codes (termed ‘algorithms’) contained in automated claims data.

Methods

A retrospective study was conducted among patients who had been dispensed asthma drugs at three HMOs. Individuals who received ≥3 dispensings of an asthma drug during any consecutive 12‐month period beginning 1 January 1994 through 20 June 2000 were identified. Information on patient age, gender, enrollment status, asthma drugs dispensed, inpatient and outpatient diagnoses and procedures were obtained from the HMO automated databases. Twelve combinations of diagnostic and billing codes (‘algorithms’) were developed using the claims data to identify potential cases of CSS. Chart reviews blinded to drug exposure were performed using a standardized abstraction form. A rheumatologist reviewed abstracted information on all subjects, and those who met two or more American College of Rheumatology (ACR) criteria for CSS were further reviewed by two clinical experts. Cases were classified as unlikely, possible, or probable/definite CSS. Each clinical expert independently rated the cases; disagreements were resolved by consensus.

Results

A total of 185 604 patients who had been dispensed asthma drugs were identified. Three hundred fifty subjects were selected for chart review, and 15 were classified as having ‘probable/definite’ CSS. The algorithms that were most successful in identifying patients with CSS were as follows: (1) two or more codes for vasculitis (13 confirmed cases from 129 reviewed; positive predictive value 10%); (2) codes for both vasculitis and neurologic symptoms (6 confirmed cases from 15 reviewed; positive predictive value 40%) and (3) codes for both eosinophilia and vasculitis (4 confirmed cases from 5 reviewed; positive predictive value 80%).

Conclusion

Automated claims data can be used to identify patients with CSS. This approach can facilitate better epidemiologic study of the risk factors for the condition. Copyright © 2003 John Wiley & Sons, Ltd.
Development of a packaging material using non‐bleed‐type antistatic ionomer
Authors: Maki Nobuyuki , Nakano Shigenori , Sasaki Haruo
Published: October 2004

Generally, plastics and plastic films are low in moisture absorption and high in electric insulation. They are inherently vulnerable to static charge build‐up, which can result in a variety of problems. We have developed a functional packaging material to solve these static problems, by using a potassium salt of ethylene ionomer, which is a non‐bleed‐type antistatic agent. Good antistatic performance was shown by evaluating a variety of electric characteristics (e.g. the static decay time, ash test and saturated electrostatic charge and half‐life) and surface resistivity. In addition, antistatic performance was achieved on the mLLDPE (non‐treated) side in a multilayer structure. This means that the use of potassium ionomer on any layers in a multilayer structure provides antistatic performance, leading to the expectation of developing a wide variety and diversity of packaging materials. Copyright © 2004 John Wiley & Sons, Ltd.