bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oral administration of resveratrol in suppression of pulmonary metastasis of BALB/c mice challenged with CT26 colorectal adenocarcinoma cells
Authors: Weng Ya‐Ling , Liao Hui‐Fen , Li Anna Fen‐Yau , Chang Ju‐Chun , Chiou Robin Y.‐Y. 
Published: October 2009

AbstractAnti‐cancer activities of resveratrol (3,4′,5‐trihydroxylstilbene) have attracted extensive research attention. Suppression of pulmonary metastasis of BALB/c mice challenged with CT26 colorectal adenocarcinoma cells achieved by oral administration of resveratrol was assessed in three separate experiments. Each mouse was challenged by tail vein injection with CT26 cells. Prior to challenge, 8‐wk‐old mice were fed with a basal diet and orally administered with resveratrol (30 mg/kg/2 days) eight or twelve times. After challenge, oral administration of resveratrol was continued until mice were sacrificed on day 20. As integrated from three experiments, 3.7% of the control mice (n=27) and 68.7% of the resveratrol‐treated mice (n=26) exhibited free of metastasis. In a second study, 8‐wk‐old BALB/c mice were orally administered with resveratrol 12 times and challenged with CT26 cells for 100 days. All control mice died but 50% of the resveratrol‐treated mice survived. The surviving mice were challenged with CT26 cells by hypodermic injection, fed with a basal diet for an additional 30 days, and sacrificed. Tumor lumps or nodules were not detected at the injection sites or in the lungs. This reveals that intrinsic vaccination‐like defense has resulted from administration of resveratrol and challenge of tumor cells.
High‐resolution 1H NMR spectroscopic investigation of a chick embryo model of neural tube development
Authors: Coen Muireann , Wevers Ron A. , Lindon John C. , Blom Henk J. 
Published: October 2009

AbstractHigh‐field 1H nuclear magnetic resonance (NMR) spectroscopy together with cryogenic probe capabilities have been applied to obtain metabolic profiles of chick embryos and to determine the suitability of the platform for profiling such mass‐limited samples. Metabolic profiles were generated for both pooled and single embryo samples at early stages of neural development, using both 600 and 800 MHz 1H NMR spectrometer platforms. High‐resolution metabolic profiles, representing metabolites from many chemical classes, including triglycerides, organic acids, carbohydrates, amino acids and nucleosides, were rapidly acquired. Neural tube defects (NTDs) are severe congenital malformations, and evidence exists for prevention of NTDs by periconceptional supplementation of the diet with folate. The molecular basis for the protective ability of folate in prevention of NTDs is not clear, although the involvement of methylation has been postulated. Thus, the metabolic profiles of chick embryos following inhibition of enzymes of the methylation cycle and the effect of their action on neural tube closure were investigated. The embryos were profiled at early stages of development, and closure of the neural tube was followed via digital imaging. Metabolic profiles of embryo samples representing both neural tube closure and the neural tube remaining open were discriminated; glucose levels were found to be significantly higher in methylation‐inhibited samples. The application of a non‐targeted metabolic profiling approach for the study of a chick embryo model of NTDs is novel and presents the exciting potential to provide metabolic insight necessary to elucidate the complex interplay of one‐carbon moiety metabolism and NTDs. Copyright © 2009 John Wiley & Sons, Ltd.
Wirkstoffsuche und Entwicklung von Vakzinierungsstrategien zur Behandlung und Prophylaxe der kutanen Leishmaniose
Authors: Schurigt Uta , Moll Heidrun 
Published: October 2009

AbstractLeishmaniose ist eine Infektionserkrankung, die durch den wachsenden Tourismus und die Zunahme von Koinfektionen mit Leishmanien und HIV weltweit an Bedeutung gewinnt. Die Entstehung resistenter Leishmanien macht die Entwicklung neuer Therapiekonzepte zu einem wichtigen Forschungsthema. Zwei Strategien werden dabei verstärkt verfolgt: (i) die Synthese neuer niedermolekularer Wirkstoffe sowie (ii) die Entwicklung protektiver Immunisierungen. Diese Forschungsarbeiten werden es ermöglichen, die Leishmaniose in Zukunft besser zu bekämpfen.
Wirkstoffe zur Behandlung der Afrikanischen Schlafkrankheit. Im letzten Jahrhundert entwickelt
Authors: Schlitzer Martin 
Published: October 2009

AbstractInsgesamt ist die Auswahl an Wirkstoffen zur Behandlung der Afrikanischen Schlafkrankheit begrenzt. Die meisten Substanzen wurden bereits in der ersten Hälfte des vorigen Jahrhunderts eingeführt. Unter Anwendung der heute gültigen Regeln, wäre wohl keine davon entwickelt, geschweige denn zugelassen worden. Nebenwirkungen und (im Fall des Melarsoprols) Resistenz sind die größten Probleme dieser Substanzen. Eine neuere Entwicklung ist die Kombination von Eflornithin mit Nifurtimox, die in ersten klinischen Tests im Spätstadium der Infektion mit T. brucei gambiense anderen Kombinationen überlegen war. Für die Therapie des Spätstadiums der Infektion mit T. brucei rhodesiense bleibt aber weiterhin nur das Melarsoprol mit all seinen Problemen.Nur eine neue Substanz (Parfuramidin), die zumindest theoretisch eine Kreuzresistenz mit Melarsoprol aufweisen könnte, ist in der klinischen Entwicklung. Ihr weiteres Schicksal ist momentan ungewiss. Zahlreiche biologische Targets und entsprechende Hemmstoffe sind beschrieben, es steht allerdings nicht zu erwarten, dass diese Entwicklungen kurzfristig zu neuen Therapien führen werden.
Was ist das Besondere am neuen Schweinegrippe‐Virus?
Authors: Winckler Thomas 
Published: October 2009

AbstractSeit April 2009 – seit Bekanntwerden der ersten Fälle der so genannten Mexikanischen Grippe – schürt ein von Mensch zu Mensch übertragbares “Schweinegrippe”‐Virus Angst vor einer Influenza‐Pandemie beim Menschen. Was ist das für ein Virus?
Chinese women's preferences for prenatal diagnostic procedure and their willingness to trade between procedures
Authors: Chan Yiu Man , Sahota Daljit Singh , Leung Tak Yeung , Choy Kwong Wai , Chan Oi Ka , Lau Tze Kin 
Published: October 2009

AbstractObjectiveTo assess Chinese women's preference for the choice of a prenatal diagnosis test, karyotyping or rapid aneuploidy, and its relationship to maternal psychological state.Study designThree hundred consenting women completed a self administered structured questionnaire which documented their psychological state and their preferred choice of diagnostic test for chromosomal abnormality using a discrete choice experiment design. Diagnostic tests were categorised according to three attributes: completeness of chromosomal information, procedure‐to‐result time interval and cost.ResultsParticipants indicated a preference towards the karyotype test irrespective of cost and procedure‐to‐result time interval. The value of obtaining the extra information provided by karyotyping above that of rapid aneuploidy was £267.82 (95% CI 226.71–323.31). Women would only accept the rapid aneuploidy test if results where available 18 days sooner than if they were undergoing a karyotyping test. Among women who traded between diagnostic tests, the value of extra chromosomal information was reduced to £153.83 (95% CI 125.81–192.19). Women with high trait anxiety scores (>40) did not preferentially select one test.ConclusionChinese women showed a strong preference towards performing a full karyotype test and having a full chromosomal assessment performed for their pregnancy. Copyright © 2009 John Wiley & Sons, Ltd.
Effect of different bases and neutralization steps on porosity and properties of collagen‐based hydrogels
Authors: Pourjavadi Ali , Kurdtabar Mehran 
Published: October 2009

AbstractThe aim of the work reported was to investigate the effect of bases and neutralization steps on hydrogel microstructures. A series of porous hydrogels with various pore sizes were prepared by neutralizing a conventional hydrogel after gel formation. Scanning electron microscopy was used to characterize the microstructure of the porous hydrogels. The morphology of the samples showed the pores were induced into the hydrogels by water evaporation and gas release resulting from the neutralization process. Experimental results indicated that the hydrogels had an absorbency of 200–220 and 48–50 g g−1 for distilled water and sodium chloride solutions, respectively. A simple method was used to prepare porous hydrogels. The prepared hydrogels are suitable for horticulture and tissue engineering applications due to their superior salt‐resisting properties. Copyright © 2009 Society of Chemical Industry
Plasma treatment‐induced fluorine‐functionalized multi‐walled carbon nanotubes to modify poly(ethylene terephthalate) obtained via in situ polymerization
Authors: Luo Ping , Jiang Kun , Wang Ke , Yang Jinghui , Xu Tao , Chen Li , Fu Qiang 
Published: October 2009

AbstractThe introduction of carbon nanotubes in a polymer matrix can markedly improve its mechanical properties and electrical conductivity, and much effort has been devoted to achieve homogeneous dispersions of carbon nanotubes in various polymers. Our group previously performed successfully fluorine‐grafted modification on the sidewalls of multi‐walled carbon nanotubes (MWCNTs), using homemade equipment for CF4 plasma irradiation. As a continuation of our previous work, in the present study CF4 plasma‐treated MWCNTs (F‐MWCNTs) were used as a nanofiller with poly(ethylene terephthalate) (PET), which is a practical example of the application of such F‐MWCNTs to prepare polyester/MWCNTs nanocomposites with ideal nanoscale structure and excellent properties. As confirmed from scanning electron microscopy observations, the F‐MWCNTs could easily be homogeneously dispersed in the PET matrix during the in situ polymerization preparation process. It was found that a very low content of F‐MWCNTs dramatically altered the crystallization behavior and mechanical properties of the nanocomposites. For example, a 15 °C increase in crystallization temperature was achieved by adding only 0.01 wt% F‐MWCNTs, implying that the well‐dispersed F‐MWCNTs act as highly effective nucleating agents to initiate PET crystallization at high temperature. Meanwhile, an abnormal phenomenon was found in that the melt point of the nanocomposites is lower than that of the pure PET. The mechanism of the tailoring of the properties of PET resin by incorporation of F‐MWCNTs is discussed, based on structure–property relationships. The good dispersion of the F‐MWCNTs and strong interfacial interaction between matrix and nanofiller are responsible for the improvement in mechanical properties and high nucleating efficiency. The abnormal melting behavior is attributed to the recrystallization transition of PET occurring at the early stage of crystal melting being retarded on incorporation of F‐MWCNTs. Copyright © 2009 Society of Chemical Industry
Analysis of interaction partners of H4 histone by a new proteomics approach
Authors: Saade Evelyne , Mechold Undine , Kulyyassov Arman , Vertut Damien , Lipinski Marc , Ogryzko Vasily 
Published: October 2009

AbstractWe describe a modification of the tandem affinity purification method for purification and analysis of multiprotein complexes, termed here DEF‐TAP (for differential elution fractionation after tandem affinity purification). Its essential new feature is the use for last purification step of 6×His‐Ni++ interaction, which is resistant to a variety of harsh washing conditions, including high ionic strength and the presence of organic solvents. This allows us to use various fractionation schemes before the protease digestion, which is expected to improve the coverage of the analyzed protein mixture and also to provide an additional insight into the structure of the purified macromolecular complex and the nature of protein–protein interactions involved. We illustrate our new approach by analysis of soluble nuclear complexes containing histone H4 purified from HeLa cells. In particular, we observed different fractionation patterns of HAT1 and RbAp46 proteins as compared with RbAp48 protein, all identified as interaction partners of H4 histone. In addition, we report all components of the licensing MCM2‐7 complex and the apoptosis‐related DAXX protein among the interaction partners of the soluble H4. Finally, we show that HAT1 requires N‐terminal tail of H4 for its stable association with this histone.
Detection of ketyl radicals using 31P NMR spin trapping
Authors: Zoia Luca , Argyropoulos Dimitris S. 
Published: October 2009

AbstractOur recent work has allowed the development of 31P NMR spin trapping techniques for the detection and, at times, absolute quantification of many oxygen‐ and carbon‐centered free radical species. These methods are based on the ability of the nitrone phosphorus compound, 5‐diisopropoxy‐phosphoryl‐5‐methyl‐1‐pyrroline‐N‐oxide (DIPPMPO), to react with free radical species and form stable radical adducts, which are suitably detected and accurately quantified using 31P NMR. Our continuing efforts have now been focused on the application of this powerful system for the trapping of ketyl radicals, which are very difficult intermediates to be detected and quantified with traditional techniques (i.e., EPR). Ketyl radicals were initially produced using photochemical reactions of acetophenone, whose excited triplet state is able to abstract hydrogen from an H donor. As such, the 31P NMR signals for the radical adducts of the DIPPMPO spin trap with the ketyl radicals were assigned. Furthermore, in an effort to confirm the structure of these adducts, their mass spectra and fragmentation patterns were carefully examined under Gas Chromatography–Mass Spectrometry (GC–MS) conditions. Subsequently, the DIPPMPO spin trapping system was applied to the oxidation of 1‐(3,4‐dimethoxyphenyl)ethanol in the presence of horseradish peroxidase (HRP), hydrogen peroxide, and 1‐hydroxybenzotriazole (HBT) as the electron carrier (mediator). Our work confirmed that the mechanism consists of a hydrogen abstraction reaction from the α position, involving the ketyl radical: during the oxidation, the hydroxyl, hydroperoxyl, and ketyl radical intermediates were all detected. These efforts demonstrate the efficacy of our methodology that provides for the first time a facile means for the detection of the otherwise elusive ketyl radical species, with important implications in biology, chemistry, and biochemistry. Copyright © 2009 John Wiley & Sons, Ltd.
The effect of the N‐substituent s‐trans to the carbonyl group of N‐methylacrylamide derivatives on the stereospecificity of radical polymerizations
Authors: Hirano Tomohiro , Nasu Shou , Morikami Akihiro , Ute Koichi 
Published: October 2009

AbstractRadical polymerization of N‐methylacrylamide (NMAAm), N,N‐dimethylacrylamide (DMAAm), and N‐methyl‐N‐phenylacrylamide (MPhAAm) was investigated in toluene at low temperatures. Atactic, isotactic, and syndiotactic polymers were obtained by the polymerization of NMAAm, DMAAm, and MPhAAm, respectively, indicating that the stereospecificity of the radical polymerization of acrylamide derivatives depended on the N‐substituents of the monomer used. From the viewpoint of monomer structure, the origin of the stereospecificity of radical polymerization of NMAAm derivatives is discussed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6534–6539, 2009
Synthesis and characterization of polyfluorenevinylene with cyano group and carbazole unit
Authors: Song Suhee , Jin Youngeup , Kim Sun Hee , Shim Joo Young , Son Sooyeon , Kim Il , Lee Kwanghee , Suh Hongsuk 
Published: October 2009

AbstractThe present investigation deals with the synthesis, characterization, and EL properties of new polyfluorenevinylenes, CzCNPFVs, with cyano‐substituted vinylene unit and carbazole pendant. In CzCNPFVs, synthesized by the Knoevenagel condensation, the carbazole pendant was introduced to improve the efficiency of reported CNPFV. The PL emission spectra of the CzCNPFVs in chloroform solution show maximum peaks at 476–479 nm. In thin films, maximum peaks of the CzCNPFVs appeared at 501–504 nm, red‐shifted around 25 nm as compared to those in solution. The emission maxima of the EL spectra of the polymers appear at around 496–504 nm. The maximum luminescence (Lmax) of CzCNPFV2 of the device with the configuration of ITO/PEDOT/CzCNPFVs/Ca/Al is 1724 cd/m2 at 8 V. The maximum luminescence efficiency of CzCNPFV1 is 0.18 cd/A. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6540–6551, 2009
Preparation of crosslinked microspheres and porous solids from hydrocarbon solutions: A new variation of precipitation polymerization chemistry
Authors: Wu Wei , Parent J. Scott , Sengupta Saurav S. , Chaudhary Bharat I. 
Published: October 2009

AbstractA new variation of precipitation polymerization is described wherein CH bond addition to a triallyl monomer contributes to molecular weight growth, thereby incorporating a significant amount of saturated hydrocarbon into the solid phase. The extent of monomer oligomerization relative to hydrocarbon addition is shown to increase with the concentration of allyl benzoate in cyclooctane. An extension to the trifunctional monomer, triallyl trimesate, results in phase separation of hydrocarbon‐monomer adducts to give a dispersed phase whose continued reactivity leads to crosslinked microspheres. The relationships between reaction conditions and solid‐phase composition and morphology are discussed. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6561–6570, 2009
Propagation rate coefficients of isobornyl acrylate, tert‐butyl acrylate and 1‐ethoxyethyl acrylate: A high frequency PLP‐SEC study
Authors: Dervaux Bart , Junker Tanja , Schneider‐Baumann Maria , Du Prez Filip E. , Barner‐Kowollik Christopher 
Published: October 2009

AbstractPulsed laser polymerization (PLP) coupled to size exclusion chromatography (SEC) is considered to be the most accurate and reliable technique for the determination of absolute propagation rate coefficients, kp. Herein, kp data as a function of temperature were determined via PLP‐SEC for three acrylate monomers that are of particular synthetic interest (e.g., for the generation of amphiphilic block copolymers). The high‐Tg monomer isobornyl acrylate (iBoA) as well as the precursor monomers for the synthesis of hydrophilic poly(acrylic acid), tert‐butyl acrylate (tBuA), and 1‐ethoxyethyl acrylate (EEA) were investigated with respect to their propagation rate coefficient in a wide temperature range. By application of a 500 Hz laser repetition rate, data could be obtained up to a temperature of 80 °C. To arrive at absolute values for kp, the Mark‐Houwink parameters of the polymers have been determined via on‐line light scattering and viscosimetry measurements. These read: K = 5.00 × 105 dL g−1, a = 0.75 (piBoA), K = 19.7 × 105 dL g−1, a = 0.66 (ptBA) and K = 1.53 × 105 dL g−1, a = 0.85 (pEEA). The bulky iBoA monomer shows the lowest propagation rate coefficient among the three monomers, while EEA is the fastest. The activation energies and Arrhenius factors read: (iBoA): log(A/L mol−1 s−1) = 7.05 and EA = 17.0 kJ mol−1; (tBuA): log(A/L mol−1 s−1) = 7.28 and EA = 17.5 kJ mol−1 and (EEA): log(A/L mol−1 s−1) = 6.80 and EA = 13.8 kJ mol−1. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6641–6654, 2009
Synthesis of polar block grafted syndiotactic polystyrenes via a combination of iridium‐catalyzed activation of aromatic CH bonds and atom transfer radical polymerization
Authors: Brownell Lacie V. , Shin Jihoon , Bae Chulsung 
Published: October 2009

AbstractA combination of iridium‐catalyzed CH activation/borylation and atom transfer radical polymerization (ATRP) was used to generate polar graft copolymers of syndiotactic polystyrene (sPS). The borylation at aromatic CH bonds of sPS and subsequent oxidation of boronate ester proceeded without negatively affecting the molecular weight properties and the tacticity of sPS. A macroinitiator suitable for ATRP could be synthesized by the esterification of 2‐bromo‐2‐methylpropionyl bromide and hydroxy‐functionalized sPS. The graft polymerizations of methyl methacrylate and tert‐butyl acrylate from the macroinitiator using ATRP afforded polar block grafted sPS materials, syndiotactic polystyrene‐graft‐poly(methyl methacrylate) (sPS‐g‐PMMA) and syndiotactic polystyrene‐graft‐poly(tert‐butyl acrylate) (sPS‐g‐PtBA). The latter was hydrolyzed to yield an amphiphilic graft copolymer, syndiotactic polystyrene‐graft‐poly(acrylic acid) (sPS‐g‐PAA). The structures of the copolymers were characterized by NMR and FTIR spectroscopies. Size exclusion chromatography and 1H NMR spectroscopy were used to study any changes in the molecular weight properties from the parent polymer. A decrease in the hydrophobicity of the graft copolymers was confirmed by water contact angle measurements. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 6655–6667, 2009
A re‐examination of the sub‐Tm exotherm in polyamide 6: The roles of thermal history, water and clay
Authors: Xie Shaobo , Séguéla Roland , Lefebvre Jean‐Marc , Gloaguen Jean‐Michel 
Published: October 2009

AbstractThe sub‐Tm exotherms in polyamide 6 (PA6) have been carefully re‐examined by differential scanning calorimetry and X‐ray diffraction, considering the effects of processing and thermal history, addition of water and clay. The results obtained cast doubt on Khanna's proposal that sub‐Tm exotherm in PA6 comes from the release of strain energy absorbed during processing, and suggested that the origin of sub‐Tm exotherm is the γ−α transformation at the premelting temperature, namely, the less thermodynamically stable γ‐form (γns) transforming into the more thermodynamically stable α‐form (αs). The presence of water or clay in PA6 samples facilitated the formation of γns at corresponding cooling rates, and enhanced the development of sub‐Tm exotherms. During the heating scan of PA6/clay composites, the initial γns can be transformed into more stable (γs)t and αs at the same time, which can be thought as the origin of their sub‐Tm events. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 2385–2393, 2009
Pulsed Breakdown and Plasma‐Aided Phenol Polymerization in Supercritical Carbon Dioxide and Sub‐Critical Water
Authors: Kiyan Tsuyoshi , Sasaki Mitsuru , Ihara Takeshi , Namihira Takao , Hara Masanori , Goto Motonobu , Akiyama Hidenori 
Published: October 2009

AbstractThis paper deals with two fundamental experimental studies with respect to plasma processes in highly pressurized carbon dioxide (CO2) and water: pulsed discharge phenomena in CO2 up to supercritical condition as a basic study of plasma production and polymerization of phenol with a pulsed discharge plasma in sub‐critical water as an application of a discharge plasma for chemical reactions. The experiments showed that: 1) the measured electrical breakdown voltage in supercritical CO2 had a relatively large dispersion compared with that in the gas and liquid phases, and was almost independent of the CO2 density, 2) the delay time for breakdown increased gradually with increasing density, and there was a large fluctuation around the sub‐critical phase or high‐pressure gas phase, 3) the highest conversion of phenol into products in the water experiments under temperatures of 301 to 525 K and pressures of 0.1 to 20 MPa was about 17% under the experimental condition of 523 K, 20 MPa and 4 000 pulsed discharge shots and 4) phenol synthesis could only be obtained at higher temperatures in pulsed discharge plasma.magnified image