bluuebunny/crossref_metadata_2025_split huggingface dataset:
Role for the α7β1 integrin in vascular development and integrity
Authors: Flintoff‐Dye Nichole L. , Welser Jennifer , Rooney Jachinta , Scowen Paul , Tamowski Susan , Hatton William , Burkin Dean J. 
Published: July 2005

AbstractThe α7β1 integrin is a laminin receptor that has been implicated in muscle disease and the development of neuromuscular and myotendinous junctions. Studies have shown the α7β1 integrin is also expressed in nonskeletal muscle tissues. To identify the expression pattern of the α7 integrin in these tissues during embryonic development, α7 integrin chain knockout mice were generated by a LacZ knockin strategy. In these mice, expression from the α7 promoter is reported by β‐galactosidase. From embryonic day (ED) 11.5 to ED14.5, β‐galactosidase was detected in the developing central and peripheral nervous systems and vasculature. The loss of the α7 integrin gene resulted in partial embryonic lethality. Several α7 null embryos were identified with cerebrovascular hemorrhages and showed reduced vascular smooth muscle cells and cerebral vascularization. The α7 null mice that survived to birth exhibited vascular smooth muscle defects, including hyperplasia and hypertrophy. In addition, altered expression of α5 and α6B integrin chains was detected in the cerebral arteries of α7 null mice, which may contribute to the vascular phenotype. Our results demonstrate for the first time that the α7β1 integrin is important for the recruitment or survival of cerebral vascular smooth muscle cells and that this integrin plays an important role in vascular development and integrity. Developmental Dynamics 234:11–21, 2005. © 2005 Wiley‐Liss, Inc.
Synthesis and Characterisation of Monodisperse Zirconia Particles
Authors: Widoniak Johanna , Eiden‐Assmann Stefanie , Maret Georg 
Published: July 2005

AbstractMonodisperse spherical ZrO2 particles were prepared by controlled hydrolysis of zirconium tetraalkoxide in alcoholic solution. Ageing the reaction solution at 60 °C for 4 h yields particles with sizes in the range between 200 and 2000 nm. The influence of various ions and surfactants on the final product was investigated. Stable suspensions of coated, monodisperse, zirconia particles were prepared by hydrolysis and subsequent polymerisation of tetraethoxysilane in an alkaline ethanol solution. Thermal analysis revealed that the weight loss of bound water occurred below 400 °C and is about 35 %. The phase transition from amorphous zirconia to the tetragonal phase proceeded at approximately 450 °C, the transition to the monoclinic phase began at about 600 °C and was completed at about 800 °C. The crystallinity of the powders was investigated by X‐ray diffraction. Electrophoretic measurements were carried out to determine the charges on the particle surface. Elementary analyses were used for further investigations. On the basis of the results obtained, the mechanism of particle formation was discussed. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis, Crystal Structure, and Magnetic Properties of a Three‐Dimensional Hydroxide Sulfate: Mn5(OH)8SO4
Authors: Fan Yong , Hua Li Guang , Yang Lei , Ming Zhang Zhi , Chen Yan , You Song Tian , Hua Feng Shou 
Published: July 2005

AbstractA 3D hydroxysulfate, Mn5(OH)8SO4, formed from a mild hydrothermal reaction has been reported. The compound crystallizes in the triclinic system P$\tilde {1}$ with cell parameters a = 7.5501(5) Å, b = 8.5558(6) Å, c = 8.6059(5) Å, α = 98.122(4)°, β = 102.370(4)°, γ = 99.646(4)°, V = 526.19(6) Å3 and Z = 2. The crystal structure consists of a 3D framework with channels along the c‐axis. In this structure, the manganese atoms in the distorted pentahedra and octahedra are interconnected by OH groups to form layers along the bc plane. These layers are further connected with MnO5 distorted pentahedra, MnO6 octahedra and [SO4]2– tetrahedra, resulting in a complicated network. The temperature dependence of the magnetic susceptibility shows a weak antiferromagnetic interaction in the compound. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis and Physico‐Chemical Properties of Novel Biocompatible AlkylD‐Mannopyranosiduronate Surfactants Derived from Alginate
Authors: Roussel Myriam , Benvegnu Thierry , Lognoné Vincent , Le Deit Hervé , Soutrel Isabelle , Laurent Isabelle , Plusquellec Daniel 
Published: July 2005

AbstractThe present article describes the preparation and the physico‐chemical properties of novel biocompatible surfactants derived from alginate for applications in detergents and cosmetics. Controlled acid hydrolysis of commercially available alginate fromLaminaria digitatagives saturated oligo‐mannuronates on a multigram scale. Subsequent one‐pot acid glycosidic bond hydrolysis, esterification and stereocontrolled Fischer glycosylation in butanol with the related oligouronates efficiently providesn‐butyl (n‐butyl α‐D‐mannopyranosiduronate) (3). Double‐tailed amphiphiles were next obtained from this key intermediate3by transesterification/transglycosylation processes in fatty alcohols. Aqueous basic and acid treatments furnished anionic or neutral single‐tailed surfactants. These original alginate‐derived amphiphiles exhibit attractive surface‐tension and foaming properties. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Development of New Amino(oxo)piperidinecarboxylate Scaffolds and Their Evaluation as ‐Turn Mimics
Authors: Verbist Bie M. P. , De Borggraeve Wim M. , Toppet Suzanne , Compernolle Frans , Hoornaert Georges J. 
Published: July 2005

AbstractIn this paper a synthetic approach for functionalised bicyclic Amino(oxo)piperidinecarboxylate (APC) systems is presented. These systems can potentially be applied as cis‐peptide bond containing β‐turn mimics. The scope and limitations of the synthetic method are discussed and the turn‐inducing properties of a model compound are evaluated by means of molecular modelling and NMR analysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Dehydrogenation of Amines to Nitriles in Aqueous Micelles
Authors: Biondini Daniele , Brinchi Lucia , Germani Raimondo , Goracci Laura , Savelli Gianfranco 
Published: July 2005

AbstractAn aqueous reaction medium, based on a surfactant solution of dimethyldodecylamine N‐oxide (DDAO) has been developed for the oxidative dehydrogenation of primary amines using NiSO4 as catalyst and K2S2O8 as oxidant. This reaction medium enhances the rate of the reaction relative to other media previously reported in the literature, which are also toxic. The reactions of various aliphatic and cyclic amines have been investigated and gave nitriles with yields of >90 % in mild conditions. The aqueous surfactant solution and reagents were recycled for future use. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
An Efficient [2+3] Cycloaddition Approach to the Synthesis of Pyridyl‐Appended Fullerene Ligands
Authors: Troshin Pavel A. , Peregudov Alexander S. , Mühlbacher David , Lyubovskaya Rimma N. 
Published: July 2005

AbstractWe have used 2‐, 3‐, and 4‐picolylamines and their various N‐substituted derivatives as substrates to generate azomethine ylides for [2+3] cycloaddition to [60]fullerene. A considerable difference in the reactivity of isomeric picolylamines was observed; however, even less reactive 3‐picolylamines afford high yields of products under acid or base catalysis. This method provides easy access to a large family of valuable ligands (pyridyl‐substituted pyrrolidinofullerenes) that can be used in the design of transition‐metal complexes and non‐covalently bonded dyads with metalloporphyrins. Unusually high yields of products and convenience of synthetic procedures (2–10 min heating the reagents at reflux in 1,2‐dichlorobenzene in air in most cases) as well as a wide synthetic potential make this reaction a good alternative to the commonly used Prato method. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Reactivity of 3‐Styrylchromones as Dienes in Diels–Alder Reactions under Microwave Irradiation: A New Synthesis of Xanthones
Authors: Pinto Diana C. G. A. , Silva Artur M. S. , Brito Cristela M. , Sandulache Angela , Carrillo José R. , Prieto Pilar , Díaz‐Ortiz Angel , de la Hoz Antonio , Cavaleiro José A. S. 
Published: July 2005

AbstractMicrowave irradiation under solvent‐free conditions induced 3‐styrylchromones to undergo Diels–Alder cycloaddition reactions with N‐methyl‐ and N‐phenylmaleimide as well as with other dienophiles. In some of these reactions the cycloadducts underwent in situ oxidation to give xanthones, whereas in other cases it was necessary to add DDQ as an oxidant. The reactions of 3‐styrylchromones with N‐methyl‐ and N‐phenylmaleimide gave the cycloadducts 4‐aryl‐1,3‐dioxo‐3a,4,11a,11b‐tetrahydropyrrolo[3,4‐c]xanthones, which were oxidised to 4‐aryl‐1,3‐dioxopyrrolo[3,4‐c]xanthones with DDQ. The reactions of 3‐styrylchromones with 2‐(2‐nitrovinyl)thiophene gave 2‐aryl‐3‐(2‐thienyl)xanthones directly through a Diels–Alder reaction followed by HNO2 elimination and oxidation. The cycloaddition reactions of 3‐styrylchromones described herein are stereoselective. The reactions of (Z)‐ and (E)‐3‐styrylchromones with N‐methylmaleimide gave, respectively, the endo and exo cycloadducts, while reactions of (Z)‐3‐styrylchromones with the less reactive dienophile N‐phenylmaleimide gave a mixture of compounds. This mixture contained the expected endo cycloadduct and another compound that was identified as the exo adduct of the reaction between the (E)‐3‐styrylchromone — obtained in situ from the isomerisation of its (Z) isomer — and N‐phenylmaleimide. The regio‐ and stereoselectivity of these cycloaddition reactions have been studied by ab initio calculations and can be understood in terms of a thermodynamically controlled reaction. Theoretical calculations are in complete agreement with the experimental results. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Selenium‐Containing Heterocycles From Isoselenocyanates: Synthesis of1,3‐Selenazolidine and Perhydro‐1,3‐selenazine Derivatives
Authors: Sommen Geoffroy L. , Linden Anthony , Heimgartner Heinz 
Published: July 2005

AbstractTreatment of ω‐halo alkylamines 9 and 10 with aryl and alkyl isoselenocyanates 6a–g in the presence of triethylamine in dichloromethane gave the corresponding 1,3‐selenazolidines 11a–g and perhydro‐1,3‐selenazines 12a–g, respectively, in good to excellent yields. Chemical and spectroscopic evidence for the structures of all new compounds are presented, and in selected examples the molecular structures have been established by X‐ray crystallography. The analogous reactions with isothiocyanates have been used for the preparation of 1,3‐thiazolidines and perhydro‐1,3‐thiazines. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Cobalt(I)‐Mediated Intramolecular [2+2+2] Cocyclizations of (Methylenecyclopropyl)diynes as an Easy Access to Cyclopropanated Oligocycles
Authors: Schelper Michael , Buisine Olivier , Kozhushkov Sergei , Aubert Corinne , de Meijere Armin , Malacria Max 
Published: July 2005

AbstractEnediynes with methylenecyclopropane moieties attached either through the three‐membered ring or the double bond smoothly underwent cobalt‐mediated [2+2+2] cocyclizations to give cyclopropane‐fused and spirocyclopropanated cobalt‐complexed tricyclo[7.3.0.02,6]dodeca‐1,6‐dienes (1,2,3,3a,4,6,7,8‐octahydro‐as‐indacenes) under relatively mild conditions in yields ranging from 31 to 94 % (6 examples). Electron‐withdrawing substituents at the acetylenic terminus of the precursor are essential for a successful oligocyclization. While diphenyloxyphosphinyl‐substituted enediynes provided tricyclo[7.3.0.02,6]dodeca‐1,6‐diene complexes as mixtures of two diastereomers in high yields, the analogous methoxycarbonyl‐substituted precursors gave only one diastereomer. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Synthesis of a Bisphthalocyanine and Its Nonlinear Optical Properties
Authors: Calvete Mario J. F. , Dini Danilo , Flom Steven R. , Hanack Michael , Pong Richard G. S. , Shirk James S. 
Published: July 2005

AbstractThe synthesis and the nonlinear optical properties of an axially substituted binuclear InCl/InCl phthalocyanine 1 with an unsymmetrical substitution pattern are described. The preparation of this new type of binuclear phthalocyanine has been carried out through a multi‐step synthetic strategy, which was specially developed for binuclear phthalocyanines. The study has been carried out with the aim of analyzing which variations of the electronic properties accompany the unsymmetrical extension of the π‐electron system of a binuclear Pc when compared to a mononuclear Pc (the complex tBu4PcInCl is here taken for comparison). The nonlinear optical properties of InCl/InCl phthalocyanine 1 in toluene were studied with the Z‐scan technique in both open‐ and closed‐aperture configurations at 532 nm with nanosecond laser pulses. The binuclear complex displayed a positive nonlinear absorption coefficient. It is found that the linear optical properties were little changed but the optical limiting effectiveness of the binuclear fused phthalocyanine 1 is lower relative to tBu4PcInCl. Explanations for such differences are given. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Regiochemical Control by Remote Substituents – A Selective Synthesis of Angularly Fused Ring Systems
Authors: Kraus George A. , Zhang Ning , Wei Jing Qiang , Jensen Jan H. 
Published: July 2005

AbstractDiels–Alder reactions of quinones 4, 7, and 15 exhibit remarkable regioselectivity. In contrast, the Diels–Alder reaction of quinone 12 showed no regioselectivity, indicating that the regioselectivities are due to electronic interactions. The selectivity is nicely explained using molecular electrostatic potentials. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Associations between small intestine cancer and other primary cancers: An international population‐based study
Authors: Scélo Ghislaine , Boffetta Paolo , Hemminki Kari , Pukkala Eero , Olsen Jorgen H. , Andersen Aage , Tracey Elizabeth , Brewster David H. , McBride Mary L. , Kliewer Erich V. , Tonita Jon M. , Pompe‐Kirn Vera , Chia Kee‐Seng , Jonasson Jon G. , Martos Carmen , Colin Didier , Brennan Paul 
Published: July 2005

AbstractCancer of the small intestine is a rare neoplasm, and its etiology remains poorly understood. Analysis of other primary cancers in individuals with small intestine cancer may help elucidate the causes of this neoplasm and the underlying mechanisms. We included 10,946 cases of first primary small intestine cancer from 13 cancer registries in a pooled analysis. The observed numbers of 44 types of second primary cancer were compared to the expected numbers derived from the age‐, gender‐ and calendar period‐specific cancer incidence rates in each registry. We also calculated the standardized incidence ratios (SIR) for small intestine cancer as a second primary after other cancers. There was a 68% overall increase in the risk of a new primary cancer after small intestine carcinoma (SIR = 1.68, 95% confidence interval [CI] = 1.47–1.71), that remained constant over time. The overall SIR was 1.18 (95% CI = 1.05–1.32) after carcinoid, 1.29 (1.01–1.63) after sarcoma, and 1.27 (0.78–1.94) after lymphoma. Significant (p < 0.05) increases were observed for cancers of the oropharynx, colon, rectum, ampulla of Vater, pancreas, corpus uteri, ovary, prostate, kidney, thyroid gland, skin and soft tissue sarcomas. Small intestine cancer as a second primary was increased significantly after all these cancers, except after oropharyngeal and kidney cancers. Although some of the excess may be attributable to overdiagnosis, it is plausible that most additional cases of second primary cancers were clinically relevant and were due to common genetic (e.g., defects in mismatch or other DNA repair pathways) and environmental (e.g., dietary) factors. © 2005 Wiley‐Liss, Inc.
Immunosurveillance is active in colorectal cancer as downregulation but not complete loss of MHC class I expression correlates with a poor prognosis
Authors: Watson Nicholas F.S. , Ramage Judith M. , Madjd Zahra , Spendlove Ian , Ellis Ian O. , Scholefield John H. , Durrant Lindy G. 
Published: July 2005

AbstractMany colorectal tumors lose or downregulate cell surface expression of MHC class I molecules conferring resistance to T‐cell‐mediated attack. It has been suggested that this phenomenon is due to in vivo immune‐tumor interactions. However, evidence of the impact of MHC class I loss on outcomes from colorectal cancer is scarce. In our study of more than 450 colorectal cancers in tissue microarray format, we have shown that both high levels of MHC class I expression and absent MHC class I expression are associated with similar disease‐specific survival times, possibly due to natural killer cell‐mediated clearance of MHC class I‐negative tumor cells. However, tumors with low level expression of MHC class I were found to confer a significantly poorer prognosis, retaining independent significance on multivariate analysis. The existence of these poor prognosis tumors, which may avoid both NK‐ and T‐cell‐mediated immune surveillance, has important implications for the design of immunotherapeutic strategies in colorectal cancer. © 2005 Wiley‐Liss, Inc.
Episode sensitivity in association with process indicators in the Finnish breast cancer screening program
Authors: Sarkeala Tytti , Hakama Matti , Saarenmaa Irma , Hakulinen Timo , Forsman Hakan , Anttila Ahti 
Published: July 2005

AbstractWe assessed the episode sensitivity of the Finnish mammography program for women aged 50–59 (partly 60–64) years and explored associations between the episode sensitivity and the screening process indicators from 1991 to 1999. For the study period, data were available from 10 screening centers. Records of 721,000 screening visits were linked to the files of the nationwide Finnish Cancer Registry from 1991 to 2001 at an individual level. The rates of screen‐detected and interval breast cancers were calculated at the first and at the subsequent screens. The episode sensitivity was determined by contrasting the incidence of interval cancers with the expected population incidence rate without screening (incidence method) and as a proportion of interval cancers out of all cancers detected (detection method). At the subsequent screens, the episode sensitivity determined by the incidence method was 54% and by the detection method 65%. The sensitivity 0–11 and 12–23 months after the screening was 70% and 38%, respectively. The episode sensitivity decreased toward the end of the study period and increased with age. The center‐specific sensitivity increased 13% per 1% absolute increase in the recall rate. In general, our study provides further information on the effectiveness of screening programs. The sensitivity estimates were comparable with those from other European service screening programs. The variability in the episode sensitivity suggests potential for variations in the future screening outcome. © 2005 Wiley‐Liss, Inc.
Detailed analysis of single‐molecule surface‐enhanced resonance Raman scattering spectra of Rhodamine 6G obtained from isolated nano‐aggregates of colloidal silver
Authors: Šašić Slobodan , Itoh Tamitake , Ozaki Yukihiro 
Published: July 2005

AbstractSurface‐enhanced resonant Raman scattering (SERRS) spectra of Rhodamine 6G (R6G) were acquired from single (aggregated) Ag colloidal particles that had been incubated with various amounts of R6G (0.1–125 nM). The spectra were investigated in detail and the evidence for a single‐molecule‐like response was found even for R6G:Ag particle ratios greatly exceeding equimolarity. After a thorough comparison with literature data, it is concluded that it is reasonable to expect a single‐molecule‐like response even for fairly ‘high’ R6G concentrations. A series of Raman images are shown and commented on with respect to bulk SERRS measurements. The problem of band assignment of single‐molecule spectra of biological species is addressed. Copyright © 2005 John Wiley & Sons, Ltd.
Resonant charge transfer on the nanoscale: studying doublet states of adsorbates by surface‐enhanced Raman scattering
Authors: Arenas J. F. , López‐Tocón I. , Castro J. L. , Centeno S. P. , López‐Ramírez M. R. , Otero J. C. 
Published: July 2005

AbstractThis paper summarizes a series of results where the main role of the charge‐transfer (CT) mechanism in the surface‐enhanced Raman scattering (SERS) of aromatic molecules is demonstrated. This mechanism consists on a photoinduced CT process between nanostructures of the metallic surface and the adsorbed molecules, giving rise to the transient formation of a radical anion of the adsorbate. A general methodology to detect the CT process in SERS is described. It is demonstrated that the SERS features are determined by the differences between the electronic properties of the neutral and the anionic molecular species. On the basis of these results, we propose to use SERS as a tool to characterize such doublet states. Copyright © 2005 John Wiley & Sons, Ltd.
An in situ reduction method for preparing novel surface‐enhanced Raman scattering substrates
Authors: Li Xiaoling , Wang Yanfei , Jia Huiying , Song Wei , Zhao Bing 
Published: July 2005

AbstractSurface‐enhanced Raman scattering (SERS)‐active substrates with high enhancement were prepared by an in situ reduction method. First, NH2OH·HCl was added as complexing agent to AgNO3 solution, then NaI was dropped in to produce an AgI colloid. Second, the self‐assembly technique was used to transfer the AgI nanoparticles on to the solid substrate and then they were reduced in situ. The UV–visible spectra show that the absorption band is asymmetric, indicating that the Ag nanoparticle size distribution on the substrate is wide, which was further confirmed by atomic force microscopy (AFM) measurements. The SERS‐active substrates with different coverages can be formed in a layer‐by‐layer electrostatic assembly by exposing positively charged surfaces to colloid solutions containing oppositely charged AgI nanoparticles. The results of AFM and UV–visible spectroscopy show that the Ag nanoparticles grow with increase in the degree of coverage and that most of them remain isolated even at high coverage. Consequently, the surface optical properties are dominated by the absorption due to the isolated Ag nanoparticles. The new substrate presents high SERS enhancement and the SERS enhancement factor was estimated to be 109. By comparison with our previous work, the important effects of stabilizers on the formation and transfer of nanoparticles are confirmed. Copyright © 2005 John Wiley & Sons, Ltd.
SERS study of hydrogen peroxide electroreduction on a Pb‐modified Au electrode
Authors: Li Xiao , Gewirth Andrew A. 
Published: July 2005

AbstractThe mechanism of the electroreduction of H2O2 on a Pb‐modified Au surface was examined by surface‐enhanced Raman spectroscopy. The measurements show the presence of lead peroxide, PbOOH+, with the maximum intensity at potential just positive of underpotentially deposited Pb, and bimetallic dihydroxide, AuPb(OH)2, at potential just positive of that where peroxide is reduced and Pb islands maximally formed on the surface. All the modes for these two species decay rapidly and even disappear as the reduction current flows. Both species are absent in solutions not containing either Pb2+ or H2O2. The edge of Pb islands on the Au surface is thus shown to be the active site for this catalysis process. These results further underscore the important role of MOH species in the peroxide electroreduction reaction. Copyright © 2005 John Wiley & Sons, Ltd.