bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic, epigenetic, and clinicopathologic features of gastric carcinomas with the CpG island methylator phenotype and an association with Epstein–Barr virus
Authors: Kusano Masanobu , Toyota Minoru , Suzuki Hiromu , Akino Kimishige , Aoki Fumio , Fujita Masahiro , Hosokawa Masao , Shinomura Yasuhisa , Imai Kohzoh , Tokino Takashi 
Published: March 2006

AbstractBACKGROUNDThe CpG island methylator phenotype (CIMP), which is characterized by simultaneous methylation of the CpG islands of multiple genes, has been recognized as one of the important mechanisms in gastrointestinal carcinogenesis.METHODSMethylation of the 5 methylated‐in‐tumors (MINT) loci and 12 tumor‐related genes in 78 primary gastric carcinomas was examined using combined bisulfite‐restriction analysis. Epstein–Barr virus (EBV)‐associated gastric tumors were detected using real‐time polymerase chain reaction analysis followed by an evaluation of the correlations between CIMP status, EBV‐association, and genetic alteration of p53 and K‐ras. The authors compared the clinicopathologic features of gastric carcinomas that had high CIMP methylation (CIMP‐H) with tumors that had low CIMP methylation (CIMP‐L) or negative CIMP methylation (CIMP‐N).RESULTSThe methylation profiles of 12 genes showed nonrandom methylation, supporting the presence of CIMP in gastric carcinoma. No p53 mutations were detected among CIMP‐H tumors, and no EBV association was detected in tumors that showed mutation of p53 and K‐ras. In a multiple logistic regression model with CIMP‐H as the dependent variable, proximal location (P = .011), diffuse type (P = .019), and less advanced pathologic TNM status (P = .043) contributed significantly to CIMP‐H. Patients who had CIMP‐N gastric tumors had a significantly worse survival than patients who had CIMP‐H tumors (P = .004) or CIMP‐L tumors (P = .012). EBV‐associated tumors were associated strongly with CIMP‐H, hypermethylation of tumor‐related genes, and no p53 or K‐ras mutation.CONCLUSIONSCIMP status appeared to be associated with distinct genetic, epigenetic, and clinicopathologic features in gastric carcinomas. The finding that gastric carcinomas arose through different molecular pathways may affect not only tumor characteristics but also patient prognosis. Cancer 2006. © 2006 American Cancer Society.
Elevated plasma big ET‐1 is associated with distant failure in patients with advanced‐stage nasopharyngeal carcinoma
Authors: Mai Hai‐Qiang , Zeng Zong‐Yuan , Zhang Chang‐Qing , Feng Kai‐Tao , Guo Xiang , Mo Hao‐Yuan , Deng Man‐Quan , Min Hua‐Qing , Hong Ming‐Huang 
Published: March 2006

AbstractBACKGROUNDEndothelin‐1 (ET‐1) is a potent vasoactive peptide and a hypoxia‐inducible angiogenic growth factor associated with the development and spread of solid tumors. The clinical significance of plasma big ET‐1 in patients with advanced‐stage nasopharyngeal carcinoma (NPC) is not known.METHODSPretreatment plasma big ET‐1 levels were measured in 62 patients with advanced‐stage NPC using a sandwich enzyme‐linked immunoassay and compared with the levels from a control group (n = 19 participants).RESULTSThe median pretreatment plasma big ET‐1 level in patients with advanced‐stage NPC was 4.6 pg/mL (range, 1.9‐15.2 pg/mL) and was significantly elevated compared with median plasma big ET‐1 levels in healthy controls, 2.6 pg/mL (1.6‐4.5 pg/mL) (P < .001). Using the upper limit (4.5 pg/mL) of control subjects as the cut‐off value, plasma big ET‐1 was ≤ 4.5 pg/mL in 29 (46.8%) patients and > 4.5 pg/mL in 33 (53.2%) patients. A pretreatment plasma big ET‐1 level > 4.5 pg/mL was associated with a significantly poorer 2‐year distant metastasis‐free survival rate (56.7% vs. 81.1%, P = .031). Multivariate analysis showed that N classification (hazard ratio [HR], 2.416; 95% confidence interval [CI], 1.071‐5.447; P = .034) and pretreatment plasma big ET‐1 level (HR, 3.151; 95% CI, 1.099‐9.028, P = .033) were independent significant prognostic factors for posttreatment distant failure in patients with advanced‐stage NPC.CONCLUSIONSPretreatment plasma big ET‐1 levels may be useful in predicting posttreatment distant failure in patients with advanced‐stage NPC. Cancer 2006. © 2006 American Cancer Society.
Spectral and Photophysical Properties of Thioxanthone in Protic and Aprotic Solvents: The Role of Hydrogen Bonds in S1‐Thioxanthone Deactivation
Authors: Krystkowiak Ewa , Maciejewski Andrzej , Kubicki Jacek 
Published: March 2006

AbstractSpectral and photophysical properties of thioxanthone (9H‐thioxanthen‐9‐one, TX) were determined in a few protic solvents (H2O, D2O, hexafluoro‐2‐propanol) and compared with those in aprotic solvents. On the basis of the time‐resolved and steady‐state emission measurements and available literature data, it has been shown that the dominant S1‐TX deactivation process in protic solvents is the formation of the S1‐complex. The important modes of deactivation of the S1‐complex are fluorescence (ϕF≈0.4–0.5) and intersystem crossing to the T1 state. The S1‐complex→S0 internal conversion plays, at most, an insignificant role in S1‐complex deactivation, which is evidenced by the absence of an isotope effect of protic solvents on the lifetime and quantum yield of fluorescence.
Binding Interactions and Raman Spectral Properties of Pyridine Interacting with Bimetallic Silver–Gold Clusters
Authors: Wu De‐Yin , Ren Bin , Tian Zhong‐Qun 
Published: March 2006

AbstractThe binding interactions between pyridine and bimetallic silver–gold clusters are investigated using density functional theory (DFT). The binding energies of pyridine–bimetallic cluster complexes indicate that the bonding depends strongly on the binding site (Au or Ag atom) and bonding molecular orbitals in a given configuration. The donation of the lone‐pair electrons of the nitrogen of pyridine to an appropriate unoccupied orbital of each metal cluster plays an important role. The low‐lying excited states and charge‐transfer states of four stable complexes of interest are calculated on the basis of a time‐dependent DFT method. In nonresonance Raman scattering processes, the influence of binding interactions on the relative Raman intensity of totally symmetric pyridine vibrational modes is discussed. These calculated relative Raman intensities are compared with observed surface‐enhanced Raman spectra of pyridine adsorbed on silver–gold alloy surfaces.
Photoisomerizable Bipyridine Ligands and Macroligands: Absorption, Photoisomerization Properties and Theoretical Study
Authors: Viau Lydie , Malkowsky Itamar , Costuas Karine , Boulin Stéphanie , Toupet Loïc , Ishow Eléna , Nakatani Keitaro , Maury Olivier , Le Bozec Hubert 
Published: March 2006

AbstractTwo 2,2′‐bipyridines, substituted at the 4,4’‐positions by p‐dialkylaminophenylazostyryl moieties p‐R2NC6H4NNC6H4‐CHCH[6 a, R2NnBu2N; 6 b, R2N(nBu)(C4H8OTHP)N; 6 c, R2N(nBu)(C4H8OH)N], were successfully synthesized by using Wadworth–Emmons reactions. The X‐ray structure of 6 a has been determined. Esterification of 6 c with 2‐bromoisobutyroylbromide afforded 6 d. This ligand was used as an initiator for the living radical polymerization of methylmethacrylate (MMA) and gave rise to macroligand 6 e. Thin films of good optical quality were obtained by the spin‐coating technique. Photoisomerization experiments were carried out on 6 a in solution and on 6 e in both solution and film, and the kinetics of photochemical (E/Z) and thermal (Z/E) isomerization were investigated. They were found to show Z–E back isomerization typical of aminoazobenzene‐type rather than of push–pull‐type molecules. Density functional theoretical (TD‐DFT) calculations were performed on model compound 6 a’ (R2NMe2N) to understand the structural and electronic transitions of the corresponding E–E, E–Z and Z–Z isomers. It was found that the E–E isomer is almost planar as observed experimentally by X‐ray diffraction, whereas the Z–Z isomer, which is 35.4 kcal mol−1 less stable than the E–E isomer, is nonplanar. The theoretical studies also reveal that several transitions of π–π*, n–π* and charge‐transfer (CT) types, are involved in the long‐wavelength transition of 6 a (E–E). The same observations can be made for the (Z–Z) isomer, and the TD‐DFT simulated spectrum fits quite nicely to the experimental, reproducing and explaining the apparition of a blue‐shifted charge‐transfer band at 390 nm.
Long‐Range Molecular Organization of an Organic Monolayer Grafted on a Mineral Substrate
Authors: Struth Bernd , Terech Pierre , Rieutord François 
Published: March 2006

AbstractStructured and functional materials are of the utmost importance for the development of microelectronic technology. We report on a method to obtain a highly ordered organic molecular layer on a mineral substrate. We took advantage of the regular array of reactive sites present at the single‐crystal surface of topaz to perform a liquid‐phase silanization reaction. The grazing‐incidence diffraction technique was used to characterize the bare and covalently coated surfaces. The ordering of the monomolecular organic layer reproduces the perfect single‐crystal structure of the cleaved surface over millimeter distances.
Linear and Two‐Photon Absorption Properties of Interacting Polar Chromophores: Standard and Unconventional Effects
Authors: Terenziani Francesca , Morone Marika , Gmouh Said , Blanchard‐Desce Mireille 
Published: March 2006

AbstractInvestigations into the effects of electrostatic interactions on linear and two‐photon absorption (TPA) properties are probed using a reference polar chromophore and different related compounds. Compounds in which a passive charge is present near the active chromophore, as well as dimers of the reference molecule, were studied. The combined experimental and theoretical investigation demonstrates that strong modulation of the properties can be attained. In particular, the TPA response of dimers is heavily affected by unconventional excitonic effects, that is, beyond the standard Heitler–London approximation. These effects, which stem from purely electrostatic interactions, lower the nonlinear optical response in the investigated case by an additional amount (up to 20 %), and are expected to enhance the TPA cross section in other supramolecular alignments. Electrostatic interactions cannot be overlooked when modelling or investigating highly concentrated and/or confined samples, as are usually needed in many applications. The correct knowledge of their effects can be exploited to guide engineering at the molecular and supramolecular level.
Cyanomethylidyne: A Reactive Carbyne Radical
Authors: Wang Jian , Ding Yi‐hong , Sun Chia‐chung 
Published: March 2006

AbstractThe cyanomethylidyne radical (CCN) has been a long‐standing subject of extensive structural and spectroscopic studies. However, its chemical reactivity has received rather little attention. Recently, we studied the reaction of CCN with the simplest alkane, CH4, which follows a mechanism of carbyne insertion–dissociation rather than that of direct H abstraction proposed by a recent experimental study. However, we are aware that alkanes like CH4 bear no electron lone pairs and thus are not ideal diagnostic molecules for distinguishing between the carbyne‐insertion and H‐abstraction mechanisms. Hence, we chose a series of σ‐bonded molecules HX (X=OH, NH2, and F) which bear electron lone pairs and are better diagnostics for carbyne‐insertion behavior. The new results at the CCSD(T)/6‐311+G(2df,p)//B3LYP/6‐311G(d,p)+ZPVE, CCSD(T)/aug‐cc‐pVTZ//B3LYP/6‐311G(d,p)+ZPVE, G2M(CC1), and MC‐QCISD//B3LYP/6‐31G(d)+ZPVE levels definitively confirm the carbyne‐insertion behavior of the CCN radical towards HX. In addition, we make the first attempt to understand the reactivity of the CCN radical toward π‐bonded molecules, using the CCN+C2H2 model reaction. This reaction involves carbenoid addition to the CC bond without a potential‐energy barrier to form a C3 three‐membered cyclic intermediate followed by H extrusion. Therefore, the reactions of CCN with both σ‐ and π‐bonded molecules conclusively show that CCN is a reactive carbyne radical and may be more reactive than the well‐known CN radical. Future experimental studies, especially on product characterization, are strongly desired to test our proposed carbyne mechanism. The studied reactions of CCN with CH4 , NH3 , H2O, and C2H2 could be of interest to combustion science and astrophysics, and they could provide efficient routes to form novel cyano‐containing molecules in interstellar space.
AFM Studies of Metal Deposition: Instantaneous Nucleation and the Growth of Cobalt Nanoparticles on Boron‐Doped Diamond Electrodes
Authors: Simm Andrew O. , Ji Xiaobo , Banks Craig E. , Hyde Michael E. , Compton Richard G. 
Published: March 2006

AbstractIn situ atomic force microscopy (AFM) is used to study the growth of cobalt nuclei on a boron doped diamond electrode under potentiostatic control. The rate of growth of the nuclei at the electrode surface is monitored using AFM as a function of time at different deposition potentials. The nucleation of cobalt nuclei is found to be “instantaneous” and the growth of the nuclei is shown to be kinetically rather than diffusionally controlled over periods of tens and hundreds of seconds. At very short times (<10 seconds) the kinetics of nucleation are apparent.
Screening of Garlic Water Extract for Binding Activity with Cholera Toxin B Pentamer by NMR Spectroscopy – An Old Remedy Giving a New Surprise
Authors: Politi Matteo , Alvaro‐Blanco Josué , Groves Patrick , Prieto Alicia , Leal J. Antonio , Cañada F. Javier , Jiménez‐Barbero Jesús 
Published: March 2006

AbstractBinding between a component of the crude hot water extract obtained from Allium sativum crushed bulbs (ASw) and cholera toxin B pentamer (CTB) was detected by STD NMR experiments. Bioassay‐oriented fractionation allowed the partial identification of a high molecular weight polysaccharide mainly composed of galactose as the bioactive complex against CTB. This work represents the first example of screening of a medicinal plant by NMR against a specific disease, and corroborates traditional medical uses of the species. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Solid‐Phase Synthesis of Decalin Scaffolds by Robinson Annulation with Immobilised Nazarov Reagents
Authors: Röttger Svenja , Waldmann Herbert 
Published: March 2006

AbstractA method for the synthesis of natural product‐inspired decalin systems on solid support is reported. It employs the Robinson annulation as key step and immobilised Nazarov reagents as key intermediates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Synthesis of Highly Functionalized Pentalenes via IntermolecularPauson–Khand Reaction
Authors: Becheanu Armand , Baro Angelika , Laschat Sabine , Frey Wolfgang 
Published: March 2006

AbstractA concise synthetic route to highly substituted pentalenones 4 and 5, respectively, is reported. The key step is a Pauson–Khand reaction of norbornadiene (7) with the functionalized acetylenes 8 to give the methanoindenone derivatives 6. 1,4‐Addition of organocuprates resulted in clean formation of 2,3‐trans‐disubstituted methanoindenones 9. After ozonolysis and reductive workup, the bis(hydroxymethyl)pentalenones 10 were obtained in moderate to good yields. A differentiation of the hydroxy groups became possible by lipase‐mediated acetylation with vinyl acetate, giving highly selectively monoacetates 4 with the acetyl group at C‐6 of the pentalene system. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Sterically Stabilized p‐Quinodimethanes by Nucleophilic Aromatic Substitution
Authors: Dyker Gerald , Hagel Marcel , Muth Oliver , Schirrmacher Christian 
Published: March 2006

AbstractTriarylmethyl cations with a sterically shielded cationic center react with selected C‐ and N‐nucleophiles under nucleophilic aromatic substitution. The resulting dipolar p‐quinodimethanes represent highly functionalized extended π systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
A study on a new AVR parameter tuning concept using on‐line measured data with the real‐time simulator
Authors: Kim Joong‐Moon , Moon Seung‐Il 
Published: March 2006

AbstractAutomatic voltage regulator (AVR) parameter tuning for voltage control of power system generators has generally been performed with the analytic methods and the simulation methods, which mostly depend on off‐line linear mathematical models of power system. However, due to the nonlinear nature of power system, the mathematical models of the excitation system may not be correct. So the excitation control system performances with the parameter set that is tuned by using the mathematical model, may not be appropriate for some operating conditions. This paper presents an AVR parameter tuning method using on‐line measured data of the excitation control system with parameter optimization technique. As this method utilizes on‐line operating data, it can overcome the limitation of model uncertainty problems of conventional method. To validate the proposed tuning concept, a scaled model excitation system is connected to the real‐time power system simulator, and the proposed tuning concept is tested. Copyright © 2006 John Wiley & Sons, Ltd.
Acute monocytic leukemia with coexpression of minor BCR–ABL1 and PICALM–MLLT10 fusion genes along with overexpression of HOXA9
Authors: Sindt Audrey , Deau Benedicte , Brahim Wajih , Staal Anne , Visanica Sorin , Villarese Patrick , Rault Jean‐Philippe , Macintyre Elizabeth , Delabesse Eric 
Published: March 2006

AbstractThe t(9;22)(q34;q11) translocation occurs in chronic myeloid leukemia (CML) and adult B‐cell acute lymphoblastic leukemia (ALL), leading to fusion of BCR to ABL1 and constitutive activation of ABL1 tyrosine kinase activity. The main BCR–ABL1 breakpoints result in P190 BCR–ABL1 or P210 BCR–ABL1 fusion proteins. The latter is found in almost all cases of CML and in one third of the cases of t(9;22)‐positive adult B‐ALL. P190 BCR–ABL1 is found in the remaining two thirds of t(9;22)‐positive adult B‐ALL cases but only exceptionally in CML. We describe here the first case of t(9;22)(q34;q11) associated with t(10;11)(p13;q14) in acute monocytic leukemia. The recurrent t(10;11)(p13;q14) translocation, usually found in acute myeloid leukemia (AML) and T‐ALL, merges PICALM to MLLT10. RT‐PCR enabled identification of PICALM–MLLT10 and BCR–ABL1 e1–a2 fusion transcripts; in the context of chronic and acute myeloid leukemia, the latter usually has a monocytic presentation. We also identified overexpression of HOXA9, a gene essential to myeloid differentiation that is expressed in PICALM–MLLT10 and MLL‐rearranged acute leukemias. This case fits with and extends a recently proposed multistage AML model in which constitutive activation of tyrosine kinases by mutations (BCR–ABL1) are associated with deregulation of transcription factors central to myeloid differentiation (HOXA9 secondary to PICALM–MLLT10). © 2006 Wiley‐Liss, Inc.
Mutations of the PTPN11 and RAS genes in rhabdomyosarcoma and pediatric hematological malignancies
Authors: Chen Yuyan , Takita Junko , Hiwatari Mitsuteru , Igarashi Takashi , Hanada Ryoji , Kikuchi Akira , Hongo Teruaki , Taki Tomohiko , Ogasawara Mizuho , Shimada Akira , Hayashi Yasuhide 
Published: March 2006

AbstractPTPN11 has been identified as a causative gene in Noonan syndrome (NS), responsible for about 50% of cases of NS. Given the association between NS and an increased risk of some malignancies, notably leukemia and probably some solid tumors including neuroblastoma (NB) and rhabdomyosarcoma (RMS), recent studies have reported that gain‐of‐function somatic mutations in PTPN11 occur in some hematological malignancies, especially de novo juvenile myelomonocytic leukemia (JMML) and in some solid tumors such as NB, although at a low frequency. In a screen for mutations of PTPN11 in 7 cell lines and 30 fresh tumors of RMS and in 25 cell lines and 40 fresh tumors of NB, we identified a missense mutation (A72T) in an embryonal RMS patient. In the RMS samples, we also detected mutations of NRAS in 1 cell line and 1 patient; both mutations were in embryonal RMSs and had no PTPN11 mutations. No mutations of PTPN11 were detected in NB. In 95 leukemia cell lines and 261 fresh leukemia samples including 22 JMMLs, 9 kinds of missense mutations were detected in 17 leukemia samples, which included 11 (50.0%) mutations in JMML samples and lower frequencies in other hematological malignancies. Furthermore, we identified 4 (18.2%) NRAS mutations and 1 (4.5%) KRAS mutation in 5 JMML samples, 1 of which had a concomitant PTPN11 mutation. Our data suggest that mutations of PTPN11 as well as RAS play a role in the pathogenesis of not only myeloid hematological malignancies but also a subset of RMS malignancies. © 2006 Wiley‐Liss, Inc.
Geoarchaeological insights from Indian Sands, a Late Pleistocene site on the southern northwest coast, USA
Authors: Davis Loren G. 
Published: March 2006

AbstractGeoarchaeological investigations of site 35CU67C at the Indian Sands locality, along Oregon's southern coast, provide many insights useful for considering various aspects of a Late Pleistocene coastal migration hypothesis. The geographic and geomorphic setting of terminal Pleistocene human occupation at Indian Sands provides important contextual examples that may aid in the discovery of other early coastal sites. During the Terminal Pleistocene, hunter–gatherers exploited naturally occurring sources of chert toolstone available at the Indian Sands locality.Stratigraphic records at Indian Sands show changes in aeolian sedimentation, pedogenesis, and landscape evolution. Taken together, these records reflect the presence of nonanalogous Terminal Pleistocene paleoenvironmental conditions, suggesting a coastline much colder and drier than today. Developing paleoenvironmental proxy records from Pleistocene‐age terrestrial deposits in coastal settings will help improve our understanding of early coastal cultural ecology. © 2006 Wiley Periodicals, Inc.
Towards a better QALY model
Authors: Abellán‐Perpiñán José‐María , Pinto‐Prades José‐Luis , Méndez‐Martínez Ildefonso , Badía‐Llach Xabier 
Published: March 2006

AbstractThis paper presents a test of the predictive validity of various classes of QALY models (i.e. linear, power and exponential models). We first estimated TTO utilities for 43 EQ‐5D chronic health states and next these states were embedded in nonchronic health profiles. The chronic TTO utilities were then used to predict the responses to TTO questions with nonchronic health profiles. We find that thepower QALY modelclearly outperformslinearandexponential QALY models. Optimal power coefficient is 0.65. Our results suggest that TTO‐based QALY calculations may be biased. This bias can be corrected using apower QALY model. Copyright © 2006 John Wiley & Sons, Ltd.
Empirical implications of response acquiescence in discrete‐choice contingent valuation
Authors: Yeung Raymond Y. T. , Smith Richard D. , Ho Lai‐Ming , Johnston Janice M. , Leung Gabriel M. 
Published: March 2006

AbstractThe use of discrete‐choice contingent valuation (CV) to elicit individuals' preference, expressed as maximum willingness‐to‐pay (WTP), although primarily developed in environmental economics, has been popular in the economic evaluation of health and healthcare. However, a concern with this method is the potential for ‘over‐estimating’ WTP values due to the presence of response acquiescence, or ‘yea‐saying’ bias. Based on a CV survey conducted to estimate physicians' valuation of clinic computerization, the extent of such bias was estimated from a within‐sample open‐ended valuation question following the respondents' discrete choice response. Analysis of this data suggests that not only was response acquiescence an issue, but also that the parametric estimation of mean and median WTP, the most common approach to estimating WTP from discrete‐choice data, would potentially magnify such bias (to various degrees depending on the distributional assumptions applied). The possible extent of CV design versus analysis in discrete‐choice methods therefore warrants further exploration. Copyright © 2006 John Wiley & Sons, Ltd.