bluuebunny/crossref_metadata_2025_split huggingface dataset:
Polaron cyclotron resonance in II–VI compounds at high magnetic fields
Authors: Miura N. , Imanaka Y. 
Published: April 2003

AbstractIn this paper, we discuss the cyclotron resonance in II–VI compounds in very high magnetic fields, in particular, those in CdS where many different anomalies were observed in high magnetic fields. High magnetic fields enable us to observe clean cyclotron resonance spectra even in low mobility crystals, thus in most II–VI semiconductors we can study the polaron effect up to the high energy range well above the LO phonon energy. Resonant polaron effect is observed prominently and we can estimate the electron–phonon coupling strength from the magnitude of the anticrossing effect. In addition to the resonant polaron interaction, it was found that cyclotron effective mass shows a peculiar temperature dependence which is explained theoretically by the combination of the electron‐phonon interaction and the impurity scattering.
Estimation of infection and recovery rates for highly polymorphic parasites when detectability is imperfect, using hidden Markov models
Authors: Smith Tom , Vounatsou Penelope 
Published: April 2003

AbstractA Bayesian hierarchical model is proposed for estimating parasitic infection dynamics for highly polymorphic parasites when detectability of the parasite using standard tests is imperfect. The parasite dynamics are modelled as a non‐homogeneous hidden two‐state Markov process, where the observed process is the detection or failure to detect a parasitic genotype. This is assumed to be conditionally independent given the hidden process, that is, the underlying true presence of the parasite, which evolves according to a first‐order Markov chain. The model allows the transition probabilities of the hidden states as well as the detectability parameter of the test to depend on a number of covariates. Full Bayesian inference is implemented using Markov chain Monte Carlo simulation. The model is applied to a panel data set of malaria genotype data from a randomized controlled trial of bed nets in Tanzanian children aged 6‐30 months, with the age of the host and bed net use as covariates. This analysis confirmed that the duration of infections with parasites belonging to the MSP‐2 FC27 allelic family increased with age. Copyright © 2003 John Wiley & Sons, Ltd.
Ontogenetic development of glutamate and GABA metabolizing enzymes in cultured cerebral cortex interneurons and in cerebral cortex in vivo
Authors: Larsson O. M. , Drejer J. , Kvamme E. , Svenneby G. , Hertz L. , Schousboe A. 
Published: April 2003

AbstractThe development of the enzymes phosphate activated glutaminase (PAG), glutamate dehydrogenase (GLDH), glutamic‐oxaloacetic‐transaminase (GOT), glutamine synthetase (GS), GABA‐transaminase (GABA‐T) and ornithine‐δ‐aminotransferase (Orn‐T) was followed in mouse cerebral cortex in vivo and in cultured mouse cerebral cortex interneurons. It was found that GLDH, GOT and Orn‐T exhibited an enhanced developmental pattern in the cultured neurons compared to cerebral cortex. The activities of PAG and GABA‐T developed in parallel in vivo and in culture but the activity of GS remained low in the cultured neurons compared to the increasing activity of this enzyme found in vivo. Compared to cerebral cortex the cultured neurons exhibited higher activities of PAG, GLDH and Orn‐T, whereas the activities of GABA‐T and GOT were lower in the cultured cells. The activity of GS in the cultured neurons was only 5–10% of the activity in cerebral cortex in vivo. It is concluded that neurons from cerebral cortex represent a reliable model system by which the metabolism and function of GABAergic neurons can be conveniently studied in a physiologically meaningful way.
Increased levels of UV‐induced protease activity in human UVAP‐1 cells exposed to gravity‐changing stress: involvement of E‐64‐sensitive proteases in suppression of UV mutagenicity
Authors: Takahashi Shunji , Zhang Hong‐Chang , Hasegawa Ritsuko , Karata Kiyonobu , Kita Kazuko , Wano Chieko , Yamaguchi Yoshitaka , Sugaya Shigeru , Nomura Jun , Ichinose Masaharu , Suzuki Nobuo 
Published: April 2003

AbstractUnder the 1 G condition, the increase in antipain‐sensitive protease activity promptly after UV (mainly 254 nm wavelength) irradiation in cultured human cells is detected and found to be one of the intriguing events involved in suppression of cell mutability. It was found that two cell lines, RSa and its variant UVAP‐1 cells are applicable; the former is hypermutable and not susceptible to protease activation, while the latter is hypomutable and susceptible. In the present study it was investigated whether the increase in protease activity by UV irradiation is also observed in hypomutable human UVAP‐1 cells exposed to gravity‐changing stress and whether the increase is involved in suppression of UV mutagenicity. Exposure of human UVAP‐1 cells to gravity‐changing stress such as free‐fall and parabolic flight prior to UV irradiation resulted in a pronounced increase in protease activity, but not to hypergravity conditions (2 and 10 G) prior to UV irradiation. To characterize the proteases, components of lysates from the cells exposed to free‐fall prior to UV irradiation were fractionated by high performance liquid chromatography, indicating two separate fractions with highly increased levels of E‐64‐sensitive protease activity. In the cells treated with E‐64 during their exposure to free‐fall, K‐ras codon 12 base substitution mutation was detected after UV irradiation, although the mutation was not detected after UV irradiation alone. Thus, the increase in E‐64‐sensitive protease activity may be involved in the suppression of UV mutagenicity in UVAP‐1 cells exposed to free‐fall.
Molecular characterization of whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) populations infesting cassava
Authors: Abdullahi I. , Winter S. , Atiri G.I. , Thottappilly G. 
Published: April 2003

AbstractBemisia tabaci (Gennadius) populations, collected from cassava and other plants in major cassava-cultivation areas of Sub-saharan Africa and from elsewhere around the world, were studied to determine their biotype status and genetic variation. Random amplified polymorphic DNA–polymerase chain reaction (RAPD–PCR) markers were used to examine the genetic structure of the populations. The dendogram obtained using the neighbour joining method (NJ) split the cassava-associated populations from the non-cassava types with a 100% bootstrap probability. Analysis of molecular variance (AMOVA) of the RAPD fragments revealed that 63.2% of the total variation was attributable to differences among populations, while the differences among groups (host) and within populations accounted for 27.1 and 9.8% respectively. Analysis of the internally transcribed spacer region I (ITS 1) of the ribosomal DNA confirmed that the cassava populations of B. tabaci populations were distinct from non-cassava populations. Experiments to establish whitefly populations on various host plants revealed that cassava-associated populations were restricted to cassava only, whereas B. tabaci from other hosts were polyphagous but did not colonize cassava. Hence, populations of B. tabaci from cassava in Africa represent a distinct group.
Ligand density modulates eosinophil signaling and migration
Authors: Holub A , Byrnes J , Anderson S , Dzaidzio L , Hogg N , Huttenlocher A 
Published: April 2003

Abstract
Eosinophils are a major component of the inflammatory response in persistent airway inflammation in asthma. The factors that determine the retention of eosinophils in the airway remain poorly understood. Elevated levels of fibronectin have been observed in the airway of patients with asthma, and the levels correlate with eosinophil numbers. To determine if fibronectin density modulates eosinophil function, we investigated the effect of fibronectin and vascular cell adhesion molecule 1 (VCAM-1) density on eosinophil migration and signaling via the p38 and extracellular regulated kinase (ERK)–mitogen-activated protein kinase (MAPK) signaling pathways. There was a dose-dependent inhibition of eosinophil spreading and migration on increasing concentrations of fibronectin but not VCAM-1. In addition, activation of p38 MAPK was inhibited at high fibronectin but not high VCAM-1 concentrations, and ERK activity was slightly reduced at high VCAM-1 and fibronectin concentrations. Together, the results demonstrate that fibronectin but not VCAM-1 inhibits eosinophil migration and signaling.
Phenotypic and functional analysis of T cells homing into the CSF of subjects with inflammatory diseases of the CNS
Authors: Giunti Debora , Borsellino Giovanna , Benelli Roberto , Marchese Monica , Capello Elisabetta , Valle Maria Teresa , Pedemonte Enrico , Noonan Douglas , Albini Adriana , Bernardi Giorgio , Mancardi Giovanni Luigi , Battistini Luca , Uccelli Antonio 
Published: April 2003

Abstract
The recruitment of lymphocytes across the blood brain barrier (BBB) is mediated by adhesion molecules and chemokines. The expression of activation markers and of chemokine receptors on T cells homing to the nervous system (NS) may help define their functional state. In the cerebrospinal fluid (CSF) of subjects with inflammatory neurological diseases (IND), including multiple sclerosis, we observed an increased number of T cells coexpressing CXCR3 and CCR5 as well as T cells with a CD45RO+ CCR7+ CD27+ memory phenotype. A subset of CCR7+ T cells coexpressed CXCR3 and CCR5. We also detected an increased number of interferon-γ-producing T cells in the CSF compared with peripheral blood, mostly but not exclusively in the CD45RO+ CCR7− CD27− compartment. T helper 1 (Th1) clones, established from the CSF of individuals with IND and from a healthy subject, similarly migrated to CXCL10, CXCL12, and CCL5. CXCL10, CXCL12, and CCL19 were increased in the CSF of individuals with neuroinflammation. These findings suggest that CSF is enriched in Th1-polarized memory T cells capable of differentiating into effector cells upon antigen encounter. These cells are recruited into the CSF by inducible chemokines. Thus, CSF represents a transitional station for T cells trafficking to and from the NS.
Rhodium‐Catalyzed Hydrogenation of Alkenes by Rhodium/Tris(fluoroalkoxy)phosphane Complexes in Fluorous Biphasic System
Authors: Sinou Denis , Maillard David , Aghmiz Ali , Masdeu i‐Bultó Anna M. 
Published: April 2003

AbstractThe reaction of [Ir(μ‐Cl)(COD)]2 with various fluorous derivatives of triphenylphosphane containing a para‐, meta‐, or ortho‐(1H,1H‐perfluoroalkoxy)‐substituted fluorous phosphane P(C6H4‐ORf)3 (Rf=CH2C7F15, CH2CH2CH2C8F17) and CO (1 atm) gives the corresponding trans‐[Ir(μ‐Cl)(CO){P(C6H4ORf)3}2]. The IR νCO values of these complexes give some information on the donor/acceptor properties of the phosphanes. These fluorous derivatives of triphenylphosphane, as well as a phosphane bearing two (1H,1H‐perfluoroalkyloxy) chains at the 3,5‐positions, were used in association with [Rh(μ‐Cl)(COD)]2 or [Rh(COD)2]PF6 in the reduction of methyl cinnamate, 2‐cyclohexen‐1‐one, cinnamaldehyde, and methyl α‐acetamidocinnamate in a two‐phase system D‐100/ethanol under 1 bar hydrogen at room temperature. Some differences in catalytic activity were observed in the reduction of methyl cinnamate, the most active catalyst being the rhodium complex containing the phosphane with the p‐fluorous ponytail. Recycling of the fluorous catalyst was possible, particularly using the p‐substituted phosphane, where no significant loss of catalyst or activity was observed, and generally with very low leaching of rhodium or phosphane in the organic phase.
Procedural complications following diagnostic coronary angiography are related to the operator's experience and the catheter size
Authors: Ammann Peter , Brunner‐La Rocca Hans P. , Angehrn Walter , Roelli Hans , Sagmeister Markus , Rickli MD Hans 
Published: April 2003

AbstractCardiac catheterization is performed routinely in hospitals all around the world. Extensive analysis of complications has been performed in the 1980s and early 1990s. However, because of the new therapeutic innovations based on advanced catheter technologies, these data may not apply to the present situation. Still, there are few data about procedural complications of diagnostic cardiac catheterization over the last 10 years. A total of 7,412 consecutive diagnostic cardiac catheterizations were performed between January 1990 and December 2000 and prospectively assessed in a registry. There were a total of 63 complications, of which 40 were minor and 23 major. Thus, the overall complication rate was 0.8%, with a mortality rate of 0%. Univariate analysis showed lower overall complication rate of senior physicians (> 500 coronary angiographies performed; OR = 0.58; 95% CI = 0.34–0.98; P = 0.04), smaller catheter size (< 6, 6, > 6 Fr: OR = 2.6; 95% CI = 1.53–4.41; P = 0.0004), and a higher rate in patients having left and right heart catheterization (OR = 2.62; 95% CI = 1.46–4.7; P = 0.003). Major complications were associated with larger catheters (< 6, 6, > 6 Fr: OR = 2.35; 95% CI = 1.0–5.51; P = 0.05), whereas vascular complications occurred more often with higher body weight (per 10 kg: OR = 1.4; 95% CI = 1.01–1.95; P = 0.04). Overall complication rate in diagnostic coronary angiography is very low and related to the experience of the performing cardiologist and catheter size. The only predicting risk factors for major complications in coronary angiography were catheter size and body weight. Cathet Cardiovasc Intervent 2003;59:13–18. © 2003 Wiley‐Liss, Inc.
Carbon−Carbon Bond Formation with Electrogenerated Nickel and Palladium Complexes
Authors: Duñach Elisabet , Franco Delphine , Olivero Sandra 
Published: April 2003

AbstractWe report coupling reactions of organic derivatives through catalysis by nickel and palladium complexes combined with electrochemical methods. Arylation, carboxylation, carbonylation, cyclisation, alkylation, and other reductive C−C bond forming reactions of organic halide derivatives, unsaturated hydrocarbons, and carbonyl derivatives, are presented. This review highlights electrosynthesis as an alternative methodology in the field of synthesis and catalysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A critique of the World Health Organisation's evaluation of health system performance
Authors: Richardson Jeff , Wildman John , Robertson Iain K. 
Published: April 2003

AbstractThe World Health Organisation's (WHO) approach to the measurement of health system efficiency is briefly described. Four arguments are then presented. First, equity of finance should not be a criterion for the evaluation of a health system and, more generally, the same objectives and importance weights should not be imposed upon all countries. Secondly, the numerical value of the importance weights do not reflect their true importance in the country rankings. Thirdly, the model for combining the different objectives into a single index of system performance is problematical and alternative models are shown to alter system rankings. The WHO statistical analysis is replicated and used to support the fourth argument which is that, contrary to the author's assertion, their methods cannot separate true inefficiency from random error. The procedure is also subject to omitted variable bias. The econometric model for all countries has very poor predictive power for the subset of OECD countries and it is outperformed by two simpler algorithms. Country rankings based upon the model are correspondingly unreliable. It is concluded that, despite these problems, the study is a landmark in the evolution of system evaluation, but one which requires significant revision. Copyright © 2002 John Wiley & Sons, Ltd.
X‐ray structural analysis of the ligand‐recognition mechanism in the dual‐affinity labeling of c‐type lysozyme with 2′,3′‐epoxypropyl β‐glycoside of N‐acetyllactosamine
Authors: Muraki Michiro , Harata Kazuaki 
Published: April 2003

AbstractIn spite of the belonging to the same c‐type lysozyme family, hen egg‐white lysozyme (HEWL) was much less susceptible to the dual‐affinity labeling with 2′,3′‐epoxypropyl β‐glycoside of N‐acetyllactosamine (Galβ1,4GlcNAc‐Epo) than human lysozyme (HL). The three‐dimensional structures of the HEWL labeled with single Galβ1,4GlcNAc‐Epo and the Glu102‐mutant HL labeled with double Galβ1,4GlcNAc‐Epo were determined by X‐ray crystallography at resolutions of 1.85 and 2.0 Å, respectively. The overall conformation and the interaction mode of the carbohydrate ligand part in the singly labeled HEWL and the doubly labeled Glu102‐mutant HL were basically identical to those of the correspondingly labeled wild‐type HL with minor alterations in some stereochemical parameters. A detailed comparison of the structures revealed the key protein–carbohydrate and carbohydrate–carbohydrate interactions essential for the dual labeling. It was suggested that the difference in the efficiency of the dual labeling was caused by the structural difference between Gln104 in HL and Asn103 in HEWL. The relevance to our previous study and the carbohydrate–carbohydrate interaction on cell‐surface membranes were discussed. Copyright © 2003 John Wiley & Sons, Ltd.
Therapeutic approaches to superantigen‐based diseases: a review
Authors: Hong‐Geller Elizabeth , Gupta Goutam 
Published: April 2003

AbstractSuperantigens secreted by the bacterial pathogen Staphyloccocus aureus are extremely potent toxins that overstimulate the host immune system by binding to the MHC class II and T cell receptors and activating a large population of T cells. Superantigen infection has been shown to be the causative agents in acute diseases, food poisoning and toxic shock syndrome, and in more chronic conditions such as inflammatory skin diseases. In addition to the toll on public health, S. aureus superantigens also represent a potential biothreat to our national security. To address these risks, a number of different therapeutic strategies have been developed that target different aspects of the pathogenic mechanism of S. aureus and superantigen infection. These therapies, which encompass strategies as diverse as production of neutralizing antibodies, inhibitory peptide/receptor design and blockage of superantigen gene transcription, are being tested for treatment of established S. aureus infections in pre‐ and post‐exposure scenarios. In this review, we will describe these different strategies and their efficacies in inhibition of superantigen‐induced effects in the host, and present the future outlook for successfully producing therapies for superantigen‐based disease. Copyright © 2003 John Wiley & Sons, Ltd.
Involvement of c‐jun N‐terminal kinase activation in 15‐deoxy‐δ12,14‐prostaglandin J2–and prostaglandin A1–induced apoptosis in AGS gastric epithelial cells
Authors: Liu Jean‐Dean , Lin Shyr‐Yi , Ho Yuan‐Soon , Pan Shiann , Hung Ling‐Fang , Tsai Shu‐Huei , Lin Jen‐Kun , Liang Yu‐Chih 
Published: April 2003

AbstractCyclopentenone prostaglandins (CyPGs), derivatives of arachidonic acid, have been suggested to exert growth‐inhibitory activity through peroxisome proliferator‐activated receptor (PPAR)‐dependent and ‐independent mechanisms. Here we examined various eicosanoids for growth inhibition and found that the terminal derivative of prostaglandin (PG) J2 metabolism, 15‐deoxy‐Δ12,14‐PGJ2 (15d‐PGJ2), and PGA1 markedly inhibited the growth and induced apoptosis in AGS gastric carcinoma cells. There were no significant increases in cell death and DNA‐fragmentation in the cells with overexpression of PPARα or PPARγ, indicating the possibility that 15d‐PGJ2 and PGA1 induced apoptosis through PPAR‐independent pathway. Moreover, 15d‐PGJ2 and PGA1 activated the c‐jun N‐terminal kinase (JNK) and caspase‐3 activity in dose‐ and time‐dependent manners. To examine further the role of JNK signaling cascades in apoptosis induced by 15d‐PGJ2 and PGA1, we transfected dominant‐negative (DN) mutants of JNK plasmid into the cells to analyze the apoptotic characteristics of cells overexpressing DN‐JNK following exposure to 15d‐PGJ2 and PGA1. Overexpression of DN‐JNK significantly repressed both endogenous JNK and caspase‐3 activity, and subsequently decreased apoptosis induced by 15d‐PGJ2 and PGA1. These results suggested that CyPGs, such as 15d‐PGJ2 and PGA1, activated JNK signaling pathway, and that JNK activation may be involved in 15d‐PGJ2‐ and PGA1‐induced apoptosis. © 2003 Wiley‐Liss, Inc.
Some Transition Metal Salts of 4,6‐Dinitrobenzofuroxan: Synthesis, Characterization and Evaluation of Their Properties
Authors: Shinde P. D. , Mehilal  , Salunke R. B. , Agrawal J. P. 
Published: April 2003

AbstractChromium, Iron and Copper salts of 4,6‐dinitrobenzofuroxan have been prepared by reacting sodium salt of 4,6‐dinitrobenzofuroxan with chromium nitrate nonahydrate, ferric nitrate nonahydrate and cupric nitrate trihydrate, respectively. The compounds have been characterized by elemental analysis, spectral data (IR and NMR) and metal content. Some properties including thermal and explosive behaviour of these compounds have been investigated and reported. Further, these molecules have also been investigated in composite propellants as burn‐rate modifiers. The preliminary data suggest that iron salt of 4,6‐dinitrobenzofuroxan is better than ferric oxide, generally used as a burn‐rate modifier for hydroxy‐terminated polybutadiene (HTPB) based composite propellants.
Isolation of rat Kupffer cells: a combined methodology for highly purified primary cultures
Authors: Valatas V. , Xidakis C. , Roumpaki H. , Kolios G. , Kouroumalis E.A. 
Published: April 2003

AbstractWe report a four‐step procedure that optimizes the methodology for isolation of highly purified rat Kupffer cells (KC). We combined the previously reported techniques of enzymatic tissue treatment, density gradient centrifugation, centrifugal elutriation and selective adherence. ED‐2 immunophenotyping and non‐specific esterase histochemistry were used for cell identification. This combination resulted in a satisfactorily high yield of 80–100×106KCs per liver, over 95% positive for ED‐2 and 98% viable cells. Cultures of isolated KCs were functionally intact and exhibited a concentration and time‐dependent LPS‐induced TNF‐α and nitric oxide production.
CR2 units of CR2 complexes are possibly associated with nucleophilic agents through reactive covalent links
Authors: Di Certo Maria Grazia , Faggioni Alberto , Barile Giuseppe 
Published: April 2003

AbstractThe human complement receptor type 2 (CR2/CD21), a transmembrane glycoprotein, associates with a variety of surface antigens and proteins in the cell membrane. We examined the possibilities that the CR2 units of CR2 complexes are associated through internal covalent links reactive with nucleophilic agents, e.g. H2O or methylamine, and that CR2‐positive cells process anti‐CR2 monoclonal antibodies (MoAbs). Data from immunoblotting and cytofluorimetry with CR2‐binding site‐specific MoAbs show that: (i) CR2‐positive Raji cells release soluble CR2 isoforms into the medium when incubated in phosphate buffered saline; (ii) despite affecting the detection of one soluble CR2 isoform, methylamine treatment of soluble CR2 allows the detection of another of its isoforms; (iii) limited pre‐treatment of cells with methylamine reveals a more heterogeneous CR2‐positive cell population or enhances the detection of CR2; (iv) cell treatment with CR2‐binding site‐specific MoAbs enhances the detection of CR2 isoform(s). The data suggest that CR2 is shed mainly as a soluble CR2 complex, in which the CR2 units link covalently and react with nucleophilic agents. Raji cells may process bound fragments (145 kDa) that are recognised by and become bound by anti‐CR2 MoAb.