bluuebunny/crossref_metadata_2025_split huggingface dataset:
Aromatic hydroxylation is a major metabolic pathway of the mycotoxin zearalenone in vitro
Authors: Pfeiffer Erika , Hildebrand Andreas , Damm Georg , Rapp Andreas , Cramer Benedikt , Humpf Hans‐Ulrich , Metzler Manfred 
Published: August 2009

AbstractZearalenone (ZEN) is a common mycotoxin, for which only reductive metabolites have been identified so far. We now report that ZEN is extensively monohydroxylated by microsomes from human liver in vitro. Two of the major oxidative metabolites arise through aromatic hydroxylation and are catechols. Their chemical structures have been unambiguously determined by using deuterium‐labeled ZEN and by comparison with authentic reference compounds. Moreover, both catechol metabolites of ZEN were substrates of the enzyme catechol‐O‐methyl transferase. One of the monomethyl ethers represented the major metabolite when ZEN was incubated with rat liver slices, thus demonstrating that catechol formation also takes place under in vivo‐like conditions. Out of ten major human cytochrome P450 (hCYP) isoforms only hCYP1A2 was able to hydroxylate ZEN to its catechols with high activity. Catechol formation represents a novel pathway in the metabolism of ZEN and may be of toxicological relevance.
Tautomeric behaviour and isotopic multiplets in the 13C NMR spectra of partially deuterated 5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones and 5‐arylazo‐2‐thioxo‐pyrimidine (1H,3H,5H)‐4,6‐diones—evidence for elucidation of tautomeric forms
Authors: Pesyan Nader Noroozi 
Published: August 2009

AbstractNMR spectra of the synthesized azo dyes, 5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (5a–g), 1,3‐dimethyl‐5‐arylazo‐pyrimidine (1H,3H,5H)‐2,4,6‐triones (6a–g), and 5‐arylazo‐2‐thioxo‐pyrimidine (1H,3H,5H)‐4,6‐diones (7a–g) were studied in (CD3)2SO (three drops of CD3OD were added into solutions of the dyes in two different concentrations). All dyes showed intramolecular hydrogen bonding. Dyes 5a–7a showed bifurcated intramolecular hydrogen bonds. Tautomeric behaviours of some of N‐methylated azo dyes (6a‐g) were studied in two different concentrations. The solvent–substrate proton exchange of dyes 5a–d, 6a and 7a–e was examined in presence of three drops of CD3OD. The dyes which were soluble in (CD3)2SO containing CD3OD showed isotopic splitting (β‐isotope effect) in the 13C NMR spectra. Copyright © 2009 John Wiley & Sons, Ltd.
Comparative analysis of neurulation: First impressions do not count
Authors: Harrington Michael J. , Hong Elim , Brewster Rachel 
Published: August 2009

AbstractThe central nervous system of vertebrate embryos originates from the neural tube (NT), a simple epithelium surrounding a central lumen. The mechanisms underlying the shaping of the NT, a process otherwise known as neurulation, have been the focus of numerous studies, using a variety of model systems. Yet, it remains unclear to what extent neurulation is conserved across vertebrates. This review provides a comparison between modes of neurulation, with a focus on cellular mechanisms. An emerging concept is that cell behaviors reveal similarities between modes of neurulation that cannot be predicted from morphological comparisons. Mol. Reprod. Dev. 76: 954–965, 2009. © 2009 Wiley‐Liss, Inc.
Modeling of Molecular Transfer in Heterophase Polymerization
Authors: Hernández Hugo F. , Tauer Klaus 
Published: August 2009

AbstractMass transfer across interfaces greatly determines the kinetics of heterophase polymerization. All molecules in the system can cross any interface as long as they possess enough energy to overcome barriers such as interfacial tension, chemical potentials, etc. Two main groups of mathematical approaches have been used to model mass transfer: macroscopic deterministic and molecular stochastic. Macroscopic modeling may use fundamental laws, thermodynamic expressions and empirical or semi‐empirical equations. Molecular models are based on the discrete character of nature and include stochastic simulation, BD or MD. Special emphasis is placed on the most relevant molecular transfer processes observed in free‐radical emulsion polymerization.magnified image
RNA splicing factors regulated by HPV16 during cervical tumour progression
Authors: Mole Sarah , McFarlane Melanie , Chuen‐Im Thanaporn , Milligan Steven G , Millan David , Graham Sheila V 
Published: August 2009

AbstractThe most prevalent human papillomaviruses (HPVs) causing cervical disease are the ‘high‐risk’ HPV types 16 and 18. All papillomaviruses express a transcription factor, E2, that can regulate viral and cellular gene expression. Recently, we demonstrated high‐risk HPV E2‐mediated transcriptional transactivation of SF2/ASF. This essential oncoprotein is a key member of a family of proteins, the SR proteins, that regulate constitutive and alternative splicing. Tight control of RNA splicing is necessary for the production of wild‐type proteins. So, aberrant expression of SR proteins is involved in the aetiology of a range of human diseases, including cancer. Here we demonstrate epithelial differentiation‐specific control of SF2/ASF in HPV16‐infected keratinocytes in organotypic raft culture and in low‐grade cervical lesions (CIN1). Further, we demonstrate HPV16 infection/differentiation‐induced up‐regulation of a specific subset of SR proteins and present evidence that HPV16 E2 controls expression of SRp20, SC35 and SRp75. Using a series of cell lines that model cervical tumour progression, we show that SF2/ASF, SRp20 and SC35 are specifically up‐regulated in a model of cervical tumour progression. These SR proteins are also over‐expressed in high‐grade cervical lesions, indicating that they may all have oncogenic functions. SR proteins could be useful biomarkers for HPV‐associated disease. Copyright © 2009 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Preparation of polypropylene fiber/banana fiber composites by novel commingling method
Authors: Paul Sherely Annie , Joseph Kuruvilla , Mathew Gem , Pothen Laly A. , Thomas Sabu 
Published: August 2009

AbstractShort natural fiber thermoplastic composites are usually fabricated by melt mixing or solution mixing followed by conventional methods like injection molding or compression molding. In melt mixing, the fibers are subjected to high shear and this damage the natural fiber. In solution mixing, the use of the organic solvent is essential and its use is hazardous. Development of a novel method commingling to prepare polypropylene (PP)/short natural fiber composite is the main objective of this study. The influence of fiber loading on the mechanical properties of the composites prepared by the above method has been evaluated. The applications and limitations of several equations to predict physical properties such as tensile strength and modulus of the composites have been described. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Poly(ethylene‐co‐vinyl acetate)/calcium phosphate nanocomposites: Thermo mechanical and gas permeability measurements
Authors: Selvin Thomas P. , Seno Jose , Murukan B. , Santhosh Aprem Abi , Sabu Thomas , Weimin Yang , Sri Bandyopadhyay 
Published: August 2009

AbstractPoly(ethylene‐co‐vinyl acetate) (EVA)/Calcium phosphate nanocomposites were prepared by melt mixing in a Brabender plasticoder. Nanoparticles of calcium phosphate were synthesized by the polymer‐mediated synthesis and characterized by X‐ray diffractometry and transmission electron microscopy. Mechanical properties such as tensile strength, tensile modulus, tear strength, etc., were measured with respect to the filler loading. Thermal stability of the composites under nitrogen atmosphere was also measured. The composites showed better thermal stability due to the nanoreinforcement. Oxygen gas permeability of the composites showed considerable decrease due to tortuous path created by the nanofillers. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Rheology, morphology, and thermal behavior of HDPE/clay nanocomposites
Authors: Rezanavaz R. , Razavi Aghjeh M.K. , Babaluo A.A. 
Published: August 2009

AbstractHDPE/Clay nanocomposites were prepared using laboratory made HDPE grafted maleic anhydride (HDPE‐g‐MA) as a compatibilizer. Rheology, morphology, and thermal behavior of nanocomposites were studied. The results showed that increasing the degree of grafted MA increased the intercalation of clay platelets leading to their exfoliation. The presence of free MA enhanced the clay dispersion via regrafting onto PE matrix. Although the presence of antioxidant improved the thermal stability of PE, it decreased the clay dispersion because of inhibition of regrafting of free MAs. The exfoliated nanocomposites exhibited higher viscosity and elasticity than those of intercalated nanocomposites. They displayed viscosity upturn and nonterminal behavior of elasticity at low frequency ranges, representative of the creation of three‐dimensional networks via the individual clay platelets and/or chain bridging between the platelets. The presence of such a network was evidenced by tan δ studies. Incorporation of clay remarkably increased the thermal stability of the PE. It was found that the effect of Hofmann elimination reaction can effectively be eliminated using the antioxidant. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
Comparison between laser‐induced nucleation of ZnS and CdS nanocrystals directly into polymer matrices
Authors: Athanassiou Athanassia , Blasi Laura , De Giorgi Milena , Caputo Gianvito , Fragouli Despina , Tsiranidou Elsa , Laera Anna Maria , Tapfer Leander , Cingolani Roberto 
Published: August 2009

AbstractThe nucleation of two kinds of crystalline nanoparticles, zinc sulfide (ZnS), and cadmium sulfide (CdS), is achieved directly into specific sites of polymer matrices after their irradiation with UV laser pulses. The starting samples consist of polymers doped with precursors of Zn or Cd thiolate that are proved to decompose after the absorption of UV light, resulting into the nanoparticles formation. The growth of the crystalline nanostructures is followed throughout the irradiation of the samples with successive incident pulses, by different methods, such as transmission electron microscopy, atomic force microscopy, confocal microscopy, and X‐ray diffraction. Special attention is paid to the difference of the formation pathways of the two kinds of nanoparticles studied, because the Cd thiolate precursor exhibits much higher absorption efficiency than the Zn thiolate one, at the applied UV wavelength. Indeed, CdS nanoparticles become evident after the very first incident UV pulses, whereas the formation of ZnS nanocrystals requires rather prolonged irradiation, always through a macroscopically nondestructive procedure for the polymer matrix. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers
What do women with diabetes know about pregnancy and contraception?
Authors: Cartwright A , Wallymahmed M , Macfarlane I , Casson I 
Published: August 2009

AbstractMaternal diabetes complicates one in 250 pregnancies in the UK. The risk of congenital malformation, stillbirth and neonatal death remains three to four times higher in women with diabetes than the background population. In 2005, a Confidential Enquiry into Maternal and Child Health report proposed that an improvement in pregnancy outcomes may be influenced by preconception care and careful planning of pregnancies. The National Service Framework for Diabetes recommended that women with diabetes be given advice about planning pregnancy and contraception annually.The aim of this audit was (1) to establish if women attending a routine diabetes clinic could recall information given to them relating to pregnancy and contraception, and (2) to ascertain if women who previously completed a pregnancy were able to recall more accurate information.A total of 100 women of child bearing age (up to age 40 years, 88% insulin treated) attending a diabetes clinic completed a questionnaire.Only 35% recalled having a discussion about contraception or pregnancy. Less than a quarter knew of risks to the baby and that good glycaemic control influenced these risks. Only 25% knew about folic acid supplements. The 31 patients who had had a previous pregnancy with diabetes had similar poor knowledge.In conclusion, two‐thirds of women of child bearing age were unable to recall having had a discussion regarding pregnancy or contraception. There was poor understanding of the risks associated with pregnancy. A previous pregnancy and antenatal care did not improve knowledge. New educational strategies for preconceptual care are needed for women with diabetes, regardless of parity. Copyright © 2009 John Wiley & Sons, Ltd.
Monitoring of drug‐associated electrolyte disturbances in a hospital
Authors: Zornic Nenad , Radojevic Danijela Jovanovic , Jankovic Slobodan , Djuric Dusan , Varjacic Mirjana , Simic Viktorija Dragojevic , Milovanovic Dragan R. 
Published: August 2009

AbstractPurposeThe aim of our study was to find drug‐associated changes in serum levels of major electrolytes using clinical‐event monitoring method.MethodsDuring 1‐year period, electrolyte disturbances in serum samples from patients of Clinical Center Kragujevac, Serbia, were monitored in central biochemical facility. A sample of 982 patients was randomly selected from total population of 43 120 patients whose electrolyte serum levels were measured in the facility during the study period.ResultsClinically important drug‐associated electrolyte disturbances were detected in 181 patient. There were 25 significant associations between the drugs and electrolyte values outside the reference range. However, only four causal connections were established: use of normal saline infusion with hypernatremia (OR 6.97, 95%CI 2.24–21.67), theophylline with acid–base disturbances (7.75, 1.46–41.02), polygeline infusion with decrease in bicarbonate levels (4.08, 1.42–11.73), and association of risperidone and hypocalcemia (4.10, 1.42–11.81).ConclusionAlthough clinical‐event monitoring method is far from optimal, it could quantify the known risks and provide evidence for credible hypothesis of drug adverse reactions, based on both relevant biological pathways and reasonable clinical thinking, as it was the case in our study. Copyright © 2009 John Wiley & Sons, Ltd.
Differential modulation of S‐nitrosoproteome of Brassica juncea by low temperature: Change in S‐nitrosylation of Rubisco is responsible for the inactivation of its carboxylase activity
Authors: Abat Jasmeet Kaur , Deswal Renu 
Published: August 2009

AbstractNitric oxide (NO), a new addition to plant hormones, affects numerous processes in planta. It is produced as a part of stress response, but its signaling is poorly understood. S‐nitrosylation, a PTM, is currently the most investigated modification of NO. Recent studies indicate significant modulation of metabolome by S‐nitrosylation, as the identified targets span major metabolic pathways and regulatory proteins. Identification of S‐nitrosylation targets is necessary to understand NO signaling. By combining biotin switch technique and MS, 20 S‐nitrosylated proteins including four novel ones were identified from Brassica juncea. Further, to know if the abiotic stress‐induced NO evolution contributes to S‐nitrosothiols (SNO), the cellular NO reservoirs, SNO content was measured by Saville method. Low temperature (LT)‐stress resulted in highest (1.4‐fold) SNO formation followed by drought, high temperature and salinity. LT induced differentially nitrosylated proteins were identified as photosynthetic, plant defense related, glycolytic and signaling associated. Interestingly, both the subunits of ribulose‐1,5‐bisphosphate carboxylase/oxygenase (Rubisco) showed an increase as well as a decrease in nitrosylation by LT. Inactivation of Rubisco carboxylase by LT is well documented but the mechanism is not known. Here, we show that LT‐induced S‐nitrosylation is responsible for significant (∼40%) inactivation of Rubisco. This in turn could explain cold stress‐induced photosynthetic inhibition.
Star‐like polyurethane hybrids with functional cubic silsesquioxanes: Preparation, morphology, and thermomechanical properties
Authors: Mya Khine Y. , Wang Yinxia , Shen Lu , Xu Jianwei , Wu Yongling , Lu Xuehong , He Chaobin 
Published: August 2009

AbstractStar‐like polyurethane (PU) hybrid films containing octafunctional cubic silsesquioxanes are prepared by polyaddition reaction between octakis(dimethylsilyloxy) silsesquioxane isopropenyldimethylbenzyl isocyanate (OS‐PDBI) and octakis(dimethylsilyloxy) hydroxypropyl silsesquioxane (HPS); and between OS‐PDBI and hexane diol (HD). The effect of incorporation of nanostructured cubic silsesquioxanes (CSSQ) on the macroscopic properties of PU film and their thermomechanical properties are investigated. The obtained hybrid films are relatively transparent. Their morphologies and properties are studied by using Fourier transform infra‐red spectroscopy (FTIR), X‐ray diffraction (XRD), atomic force microscopy (AFM), thermogravimetry (TGA), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA) and contact angle measurements. The formation of urethane linkage disrupts the three‐dimensional ordered structure of CSSQ in the hybrid film. AFM images show clearly that no phase separation in the macroscopic level for both PU hybrid films. TGA and DMA analyzes indicate that the incorporation of octafunctional silsesquioxane in PU hybrid film provides enhanced thermal stability and increased crosslink density. Moreover, the existence of cage structure also improves oxidation resistance and mechanical strength. The incomplete reaction between OS‐PDBI and HPS due to the steric hindrance of highly branched rigid CSSQ could result in a slight decrease in initial decomposition temperature. Furthermore, hardness and out‐of‐plane compressive modulus are also investigated by nanoindentation. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4602–4616, 2009
Three‐cationic carbocyanine dyes as sensitizers in very efficient photoinitiating systems for multifunctional monomer polymerization
Authors: Kabatc Janina , Pączkowski Jerzy 
Published: August 2009

AbstractThis article is focused on the description of the synthesis, spectroscopic, electrochemical properties, and the free radical photoinitiation abilities of new three‐cationic carbocyanine dyes. A new synthestic strategy for preparation of symmetrical cyanine dyes has been developed based on the 2‐methylbenzothiazole, 2‐methylbenzoxazole and 2,3,3‐trimethylindolinium quaternization by α‐bromo‐ω‐tertiary ammonium salts followed by the condensation of obtained product with triethyl ortho‐formate. Resulted dyes possess in one molecule three quaternary nitrogen atoms, for example, they are three‐cationic in character. Novel three‐cationic symmetric carbocyanine dyes paired with n‐butyltriphenylborate anions are very efficient photoinitiators of free radical polymerization of acrylate monomers, for example, (TMPTA) when irradiated with the visible emission of an argon‐ion laser. The photoinitiating abilities of the novel photoredox pairs were compared to the photoinitiation properties of their monocationic equivalents, for example, N,N′‐diethylthia‐, N,N′‐diethyloxa‐ and N,N′‐dimethylindocarbocyanine n‐butyltriphenylborates (SB2, OB2, and IB2) and also compared to the initiation ability of Rose Bengal derivative, for example, typical triplet state photoinitiator. The kinetic studies clearly demonstrated that the three‐cationic carbocyanine borate photoredox pairs exhibit a significant increase in the efficiency of TMPTA free radical polymerization in comparison to the photoredox pairs containing structurally related, mono‐cationic carbocyanine borates. It was also shown that, the addition of a second coinitiator to the cyanine borate salts enhances their photoinitiating abilities. The best results were obtained for three cationic carbocyanine borates in the presence of second coinitiator being N‐methoxypyridinium n‐butyltriphenylborate. The photoinitiating abilities of the systems of these types are more effective than those composed of carbocyanine cation/borate anion exclusively. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4636–4654, 2009
Synthesis and characterization of a poly(GMA)‐graft‐poly(Z‐L‐lysine) graft copolymer with a rod‐like structure
Authors: Tu You‐Liang , Wang Cheng‐Chien , Chen Chuh‐Yung 
Published: August 2009

AbstractThis study applied the macromonomers and glycidyl methacrylate (GMA) to synthesize a series of the graft copolymers, poly(GMA)‐graft‐poly(Z‐L‐lysine), and investigated the conformation of the graft copolymer. The graft copolymers were synthesized with different GMA monomer ratios (28 to 89%) and different degrees of polymerization (DP) (8 to 15) of the poly(Z‐L‐lysine) side chain to analyze secondary structure relationships. Atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and both wide angle and small angle X‐ray scattering spectroscopy (WAXS, SAXS) were used to investigate the relationship between the microstructure and conformation of the graft copolymers and the different monomer ratios and side chain DP. In AFM images, n8‐G89 (the graft copolymer containing 89% GMA units and the macromonomer DP is 8) showed tiny and uniform rod‐like structures, and n14‐G43 (the graft copolymer containing 43% GMA units and the macromonomer DP is 14) showed uniform rod‐like structures. FTIR spectra of the graft copolymers showed that the variations of α‐helix and β‐sheet secondary structures in the graft copolymers relate to the monomer ratios of the graft copolymers. However, the X‐ray scattering patterns indicated that the graft copolymer conformations were mainly dependent on the poly(Z‐L‐lysine) side chain length, and these results were completely in accordance with the AFM images. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4655–4669, 2009
Self‐assembly of H‐bonded side‐chain and cross‐linking copolymers containing diblock‐copolymeric donors and single/double H‐bonded light‐emitting acceptors
Authors: Lin Hong‐Cheu , Jiang Meng‐Dan , Wu Shen‐Chang , Jou Leng‐Long , Chou Kai‐Pin , Huang Ching‐Mao , Wei Kung‐Hwa 
Published: August 2009

AbstractA series of diblock‐copolymers were synthesized through anionic polymerization of styrene and tert‐butyl methacrylate (tBuA) with different monomer ratios, and analogous block‐copolymeric derivatives (PS‐b‐PAA)s with monofunctional carboxylic acid groups were obtained by further hydrolyzation as hydrogen‐bonded (H‐bonded) proton donors. Via H‐bonded interaction, these diblock‐coplymeric donors (PS‐b‐PAA)s were incorporated with luminescent mono‐pyridyl/bis‐pyridyl acceptors to form single/double H‐bonded supramolecules, that is, H‐bonded side‐chain/cross‐linking copolymers, respectively. The supramolecular architectures formed by donor polymers and light‐emitting acceptors were influenced by the ratio of acid blocks in the diblock copolymeric donors and the type of single/double H‐bonded light‐emitting acceptors. Their thermal and luminescent properties can be adjusted by H‐bonds, and more than 100 nm of red‐shifted photoluminescence (PL) emissions were observed, which depend on the degrees of the H‐bonding interactions. Self‐assembled phenomena of amphiphilic dibolck copolymers and their H‐bonded complexes were confirmed by TEM micrographs, and supramolecular microphase separation of spherical micelle‐like morphology was demonstrated to affect the photophysical properties. Polymer light‐emitting diode (PLED) devices containing H‐bonded complexes showed electroluminescence (EL) emissions of 503–560 nm under turn‐on voltages of 7.5–9.0 V, maximum power efficiencies of 0.23–0.37 cd/A (at 100 mA/cm2), and maximum luminances of 318–519 cd/m2 (around 25 V). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4685–4702, 2009