bluuebunny/crossref_metadata_2025_split huggingface dataset:
Temperature‐dependent specific transport of levofloxacin in human intestinal epithelial LS180 cells
Authors: Fukumori Shiro , Masago Miki , Ishida Kazuya , Kayano Yuichiro , Taguchi Masato , Hashimoto Yukiya 
Published: September 2009

AbstractIt was reported previously that specific levofloxacin uptake in Caco‐2 cells was inhibited by nicotine, enalapril, L‐carnitine and fexofenadine. The aim of the present study was to characterize the cellular uptake of levofloxacin using another human intestinal cell line, LS180. Levofloxacin uptake in LS180 cells was temperature‐dependent and optimal at neutral pH, but was Na+‐independent. The rank order of inhibitory effects of the four compounds on [14C] levofloxacin uptake in LS180 cells was nicotine>enalapril>L‐carnitine>fexofenadine, which is consistent with that in Caco‐2 cells. The mRNA levels of OATP1A2, 1B1, 1B3 and 2B1 in LS180 cells were markedly different from those in Caco‐2 cells, and OATP substrates/inhibitors had no systematic effect on the levofloxacin uptake. The mRNA levels of OCTN1 and 2 in LS180 cells were similar to those in Caco‐2 cells. However, the inhibitory effect of nicotine on L‐[3H]carnitine uptake was much less potent than that of unlabeled L‐carnitine. These results indicate that the specific uptake system for levofloxacin in LS180 cells is identical/similar to that in Caco‐2 cells, but that OATPs and OCTNs contribute little to levofloxacin uptake in the human intestinal epithelial cells. Copyright © 2009 John Wiley & Sons, Ltd.
Nrf2 plays an important role in coordinated regulation of Phase II drug metabolism enzymes and Phase III drug transporters
Authors: Shen Guoxiang , Kong Ah‐Ng 
Published: September 2009

AbstractThe nuclear transcription factor E2‐related factor 2 (Nrf2) has been shown to play pivotal roles in preventing xenobiotic‐related toxicity and carcinogen‐induced carcinogenesis. These protective roles of Nrf2 have been attributed in part to its involvement in the induction of Phase II drug conjugation/detoxification enzymes as well as antioxidant enzymes through the Nrf2‐antioxidant response element (ARE) signaling pathways. This review summarizes the current research status of the identification of Nrf2‐regulated drug metabolism enzymes (DMEs), especially Phase II DMEs, and Phase III drug transporters. In addition, the molecular mechanisms underlying the coordinated regulation of Phase II DMEs and Phase III transporters will also be discussed based on findings published in the literature. Copyright © 2009 John Wiley & Sons, Ltd.
Interelectrode distance and warning signal interval and the evaluation of clinical electrical shock
Authors: Duker Pieter , Mulder Monique , Scheffer Nienke 
Published: September 2009

AbstractContingent shock is used on a small scale for behaviors that may lead to severe damages to one's body or to others. Research efforts focus on exploring variables that control the evaluation of electrical shocks. This study focuses on two practical questions, that is, whether the distance between the electrodes would influence the evaluation of shock and whether using a variable time interval in the administration would influence the evaluation of shock. Results reveal that both investigated variables control the evaluation of shock. Multiple shocks appear to produce a stronger sensation than single shocks, a phenomenon that was also revealed in previous studies. Copyright © 2009 John Wiley & Sons, Ltd.
Bioremediation of bacteria pollution using the marine sponge Hymeniacidon perlevis in the intensive mariculture water system of turbot Scophthalmus maximus
Authors: Zhang Xichang , Zhang Wei , Xue Lingyun , Zhang Bi , Jin Meifang , Fu Wantao 
Published: September 2009

AbstractSessile filter‐feeding marine sponges (Porifera) have been reported to possess high efficiency in removing bacteria pollution from natural or aquaculture seawater. However, no investigation has been carried out thus far in a true mariculture farm water system. Therefore this study sought to investigate the ability of the marine sponge Hymeniacidon perlevis to bioremediate the bacteria pollution in the intensive aquaculture water system of turbot Scophthalmus maximus. Sponge specimens were hung in fish culture effluent at different temperature to investigate the optimal temperature condition for bacteria removal by H. perlevis. Turbots S. maximus were co‐cultured with sponge H. perlevis in 1.5 m3 of water system at 15–18°C for 6 weeks to control the growth of bacteria. It was found that H. perlevis was able to remove pathogenic bacteria efficiently at 10–20°C, with a maximal removal of 71.4–78.8% of fecal coliform, 73.9–98.7% of pathogenic vibrio, and 75.0–83.7% of total culturable bacteria from fish‐culture effluent at 15°C; H. perlevis continuously showed good bioremediation of bacteria pollution in the S. maximus culture water system, achieving removal of 60.0–90.2% of fecal coliform, 37.6–81.6% of pathogenic vibrio, and 45.1–83.9% of total culturable bacteria. The results demonstrate that H. perlevis is an effective bioremediator of bacteria pollution in the turbot S. maximus culture farm water system. Biotechnol. Bioeng. 2010;105: 59–68. © 2009 Wiley Periodicals, Inc.
Design of a cytochrome P450BM3 reaction system linked by two‐step cofactor regeneration catalyzed by a soluble transhydrogenase and glycerol dehydrogenase
Authors: Mouri Tsuyoshi , Shimizu Takeshi , Kamiya Noriho , Goto Masahiro , Ichinose Hirofumi 
Published: September 2009

AbstractA cytochrome P450BM3‐catalyzed reaction system linked by a two‐step cofactor regeneration was investigated in a cell‐free system. The two‐step cofactor regeneration of redox cofactors, NADH and NADPH, was constructed by NAD+‐dependent bacterial glycerol dehydrogenase (GLD) and bacterial soluble transhydrogenase (STH) both from Escherichia coli. In the present system, the reduced cofactor (NADH) was regenerated by GLD from the oxidized cofactor (NAD+) using glycerol as a sacrificial cosubstrate. The reducing equivalents were subsequently transferred to NADP+ by STH as a cycling catalyst. The resultant regenerated NADPH was used for the substrate oxidation catalyzed by cytochrome P450BM3. The initial rate of the P450BM3‐catalyzed reaction linked by the two‐step cofactor regeneration showed a slight increase (approximately twice) when increasing the GLD units 10‐fold under initial reaction conditions. In contrast, a 10‐fold increase in STH units resulted in about a 9‐fold increase in the initial reaction rate, implying that transhydrogenation catalyzed by STH was the rate‐determining step. In the system lacking the two‐step cofactor regeneration, 34% conversion of 50 μM of a model substrate (p‐nitrophenoxydecanoic acid) was attained using 50 μM NADPH. In contrast, with the two‐step cofactor regeneration, the same amount of substrate was completely converted using 5 μM of oxidized cofactors (NAD+ and NADP+) within 1 h. Furthermore, a 10‐fold dilution of the oxidized cofactors still led to approximately 20% conversion in 1 h. These results indicate the potential of the combination of GLD and STH for use in redox cofactor recycling with catalytic quantities of NAD+ and NADP+. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Prokaryotic expression, in vitro folding, and molecular pharmacological characterization of the neuropeptide Y receptor type 2
Authors: Schmidt Peter , Lindner Diana , Montag Cindy , Berndt Sandra , Beck‐Sickinger Annette G. , Rudolph Rainer , Huster Daniel 
Published: September 2009

AbstractG protein‐coupled receptors (GPCRs) are a class of membrane proteins that represent a major target for pharmacological developments. However, there is still little knowledge about GPCR structure and dynamics since high‐level expression and characterization of active GPCRs in vitro is extremely complicated. Here, we describe the recombinant expression and functional folding of the human Y2receptor from inclusion bodies ofE. colicultures. Milligram protein quantities were produced using high density fermentation and isolated in a single step purification with a yield of over 20 mg/L culture. Extensive studies were carried out on in vitro refolding and stabilization of the isolated receptor in detergent solution. The specific binding of the ligand, the 36 residue neuropeptide Y (NPY), to the recombinant Y2receptors in micellar form was shown by several radioligand affinity assays. In competition experiments, an IC50value in low nanomolar range could be determined. Further, aKDvalue of 1.9 nM was determined from a saturation assay, where NPY was titrated to the recombinant Y2receptors. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Interactions between surfactants and biomass during liquid–liquid extraction
Authors: Pursell Mark R. , Mendes M. Alcina , Stuckey David C. 
Published: September 2009

AbstractFermentation systems can contain may surface‐active compounds that can interfere with downstream separation processes. This work examines the interactions that can occur between surfactants and biomass during solute mass transfer in a liquid–liquid extraction system. Adding the surfactants sodium dodecyl sulfate and dodecyl trimethyl ammonium bromide to the aqueous phase caused a substantial increase in the mass transfer of chloramphenicol between water and octanol. Further investigation of the interfacial region using an optical Schlieren apparatus revealed that these increases were due to interfacial turbulence that gave rise to a rapid surface renewal convective mass transfer mechanism. When microbial biomass was present with sodium dodecyl sulfate, an increase in the mass transfer rate was again found, however, to a lesser extent. In contrast, dodecyl trimethyl ammonium bromide did not promote mass transfer and it is postulated that electrical interactions between the surfactant and the cell surface prevented adsorption of either at the interface. The interaction between the antifoaming agent polypropylene glycol 2000 and extraction system components was also investigated, with both positive and negative effects being recorded under varying conditions. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Construction of a recombinant autolytic wine yeast strain overexpressing the csc1‐1 allele
Authors: Cebollero Eduardo , Gonzalez‐Ramos Daniel , Gonzalez Ramon 
Published: September 2009

AbstractDuring the aging step of sparkling wines and wines aged on lees, yeast cells kept in contact with the wine finally die and undergo autolysis, releasing cellular compounds with a positive effect on the wine quality. In view of the interest of autolysis for wine properties, biotechnologists have tried to improve autolytic yield during winemaking. In this work we used genetic engineering techniques to construct an autolytic industrial strain by expressing the csc1‐1 allele from the RDN1 locus. The expression of this mutant allele, that causes a “constitutive in autophagy phenotype,” resulted in accelerated autolysis of the recombinant strain. Although autophagic phenotype due to csc1‐1 expression has been reported to require the mutant allele in multicopy, autolytic acceleration was achieved by expressing only one or two copies of the gene under the control of the constitutive promotor pTDH3. The acceleration of autolysis together with the unaltered fermentative capacity, strongly supported the overexpression of csc1‐1 allele as a strategy to obtain wines with aged‐like properties in a shortened time. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Vibrational and electronic optical activity of the chiral disulphide group: Implications for disulphide bridge conformation
Authors: Bednárová Lucie , Bouř Petr , Maloň Petr 
Published: September 2009

AbstractUsing dihydrogendisulphide (H2S2), dimethyl‐ ((CH3)2S2), and diethyldisulphide ((CH3CH2)2S2)as model molecules, theoretical ECD, VCD, and ROA spectra of nonplanar disulphides were calculated by DFT methods. Most of the calculated electronic and vibrational chiroptical features suffer an equivocal relation between calculatedsigns of ECD, VCD, or ROA and the sense of disulphide nonplanarity as noted earlier for low‐lying ECD bands. This is a consequence of local C2 symmetry of a disulphide group causing most electronic and vibrational transitions to occur as pairs falling to alternative A, B symmetry species, which become degenerate and switch their succession (and consequently the observed chiroptical sign pattern) at the energetically most favorable perpendicular conformation. According to present calculations, the key to resolving this ambiguity may involve the SS stretching vibrational mode at ∼500 cm−1. The relation of signs of the relevant VCD and ROA features to sense of disulphide chirality seems simpler and less ambiguous. The right‐handed arrangement of the SS group (0 < χSS < 180°) results in mostly negative VCD signals. Although relation to ROA still suffers some ambiguity, it gets clearer along the series H2S2–(CH3)2S2–(CH3CH2)2S2. ROA is also attractive for the analysis of disulphide‐containing peptides and proteins, because applying it to aqueous solutions is not problematic. Chirality, 2010. © 2009 Wiley‐Liss, Inc.
Synthesis, chiroptical properties, and their theoretical simulation of some highly rotating benzotricamphor derivatives
Authors: Mazzeo Giuseppe , Giorgio Egidio , Rosini Carlo , Fabris Fabrizio , Fregonese Erica , Toniolo Umberto , De Lucchi Ottorino 
Published: September 2009

AbstractThe large molecules 1–3 (69, 90, and 102 atoms, respectively), prepared by cyclotrimerization of enantiomerically pure derivatives of (−)‐bornyl acetate, show intense ECD spectra, high optical rotation (OR) values (200–1300, in absolute value) dominated in sign and order of magnitude by the lowest‐energy Cotton effects, that is, they are the ideal candidates to test the reliability of our “approximate” (TDDFT/B3LYP/6‐31G* or smaller basis set) approach to the calculation of chiroptical properties. As a matter of fact, a correct simulation of the OR values and ECD spectra of 1 and 2 can be obtained even using STO‐3G basis set and semiempirical or molecular mechanics input geometries: for 1, at the TDDFT/B3LYP/STO‐3G level, the OR values are of the order of 500–550, versus an experimental value ranging between 660 and 690, depending on the solvent. On the contrary, the case of 3 (exp. OR between −1330 and −1500) is really complex (for instance, the OR values range between −3216 and −729 (TDDFT/B3LYP/6‐31G* calculations) or −1824 and −444 (TDDFT/B3LYP/STO‐3G calculations)), making the comparison between calculated and experimental values more difficult. The behavior of 3 is due to its molecular flexibility, whereas 1 is a really rigid molecules and 2 behaves (vide infra) as it were a rigid system. These observations strongly indicate that the conformational freedom constitutes one of the major difficulties for a correct but simple simulation of the chiroptical properties. Chirality 21:E86–E97, 2009. © 2009 Wiley‐Liss, Inc.
Exploring Chemical Substructures Essential for hERG K+Channel Blockade by Synthesis and Biological Evaluation of Dofetilide Analogues
Authors: Shagufta  , Guo Dong , Klaasse Elisabeth , de Vries Henk , Brussee Johannes , Nalos Lukáš , Rook Martin B. , Vos Marc A. , van der Heyden Marcel A. G. , IJzerman Adriaan P. 
Published: September 2009

AbstractIn this study we followed a new approach to analyze molecular substructures required for hERG channel blockade. We designed and synthesized 40 analogues of dofetilide (1), a potent hERG potassium channel blocker, and established structure–activity relationships (SAR) for their interaction with this important cardiotoxicity‐related off‐target. Structural modifications to dofetilide were made by diversifying the substituents on the phenyl rings and the protonated nitrogen and by varying the carbon chain length. The analogues were evaluated in a radioligand binding assay and SAR data were derived with the aim to specify structural features that give rise to hERG toxicity.
Exploring the performance of massively multithreaded architectures
Authors: Bokhari Shahid , Saltz Joel 
Published: September 2009

AbstractWe present a new scheme for evaluating the performance of multithreaded computers and demonstrate its application to the Cray MTA‐2 and XMT supercomputers. Our scheme is based on the concept of clock cycles per element,\documentclass{article}\footskip=0pc\pagestyle{empty}\begin{document}${\cal C}$\end{document}, plotted againstbothproblem sizeandthe number of processors. This scheme clearly shows if an implementation has achieved its asymptotic efficiency and is more general than (but includes) the commonly used speedup metric. It permits the discovery of any imperfections in both the software as well as the hardware, and is expected to permit a unified comparison of many different parallel architectures. Measurements on a number of well‐known parallel algorithms, ranging from matrix multiply to quicksort, are presented for the MTA‐2 and XMT and highlight some interesting differences between these machines. The performance of sequence alignment using dynamic programming is evaluated on the MTA‐2, XMT, IBM x3755 and SGI Altix 350 and provides a useful comparison of the capabilities of the Cray machines with more conventional shared memory architectures. Copyright © 2009 John Wiley & Sons, Ltd.
An application of univariate marginal distribution algorithm in MIMO communication systems
Authors: Bashir Sajid , Naeem Muhammad , Khan Adnan Ahmed , Shah Syed Ismail 
Published: September 2009

AbstractThe paper discusses a sequence detector based on univariate marginal distribution algorithm (UMDA) that jointly estimates the symbols transmitted in a multiple input multiple output (MIMO) communication system. While an optimal maximum likelihood detection using an exhaustive search method is prohibitively complex, it has been shown that sphere decoder (SD) achieves the optimal bit error rate (BER) performance with polynomial time complexity for smaller array sizes. However, the worst‐case complexity of SD is exponential in the problem dimensions, this brings in question its practical implementation for larger number of spatial layers and for higher‐order signal constellation. The proposed detector shows promising results for this overly difficult and complicated operating environment, confirmed through simulation results. A performance comparison of the UMDA detector with SD is presented for higher‐order complex MIMO architectures with limited average transmit power. The proposed detector achieves substantial performance gain for higher‐order systems attaining a near optimal BER performance with reduced computational complexity as compared with SD. Copyright © 2009 John Wiley & Sons, Ltd.
The effects of audiobooks on the psychosocial adjustment of pre‐adolescents and adolescents with dyslexia
Authors: Milani Anna , Lorusso Maria Luisa , Molteni Massimo 
Published: September 2009

AbstractThe objective of the present research study was to understand what benefits the use of audiobooks (both school‐books and books of various genres, recorded on digital media) could bring to preadolescents and adolescents with developmental dyslexia. Two groups, each consisting of 20 adolescents, were compared. The experimental group used the audiobooks, while the control group continued to use normal books. After 5 months of experimental training, the experimental group showed a significant improvement in reading accuracy, with reduced unease and emotional–behavioural disorders, as well as an improvement in school performance and a greater motivation and involvement in school activities. Copyright © 2009 John Wiley & Sons, Ltd.
EU environmental state aid policy: wide implications, narrow participation?
Authors: Flåm Karoline Hægstad 
Published: September 2009

AbstractThis article investigates the 2008 reform of the EU's environmental state aid guidelines, with an eye to determining the degree of external pressure and lobbying towards environmental state aid policies. What is found is a strikingly low level of external pressure on the policy field, not least on the part of the private sector. In fact, EU environmental state aid policy is largely the making of a few Commission officials, without much external ‘interference’. The article discusses possible reasons for this, and asks whether state aid policy‐making might be marked less by clear and established stakeholder interests or stakeholders' utility maximizing, and more by stakeholders constrained by bounded rationality. Copyright © 2009 John Wiley & Sons, Ltd and ERP Environment.
Maleamate(–1) and Maleate(–2) Copper(II)–2,2′‐Bipyridine Complexes: Synthesis, Reactivity and Structural and Physical Studies
Authors: Lazarou Katerina N. , Boudalis Athanassios K. , Perlepes Spyros P. , Terzis Aris , Raptopoulou Catherine P. 
Published: September 2009

AbstractA systematic investigation of the 1:2:1:2 Cu(NO3)·2.5H2O/H2L/bpy/LiOH·H2O (H2L = maleamic acid) reaction system in MeCN/H2O was carried out. The compounds [Cu2(HL)2(bpy)2(H2O)2](NO3)2 (1), [Cu2(HL)2(bpy)2(H2O)2](NO3)2·2H2O (1·2H2O), [Cu2Li2(L′)2(bpy)2(H2O)6][Cu2(HL)2(bpy)2(H2O)2](NO3)4 (2), [Cu4(L′)2(NO3)2(bpy)4(H2O)2](NO3)2·2H2O (3·2H2O) and [Cu(L′)(bpy)]n·2nH2O (4·2nH2O) were isolated, depending on the crystallization method employed. Complexes 2, 3·2H2O and 4·2nH2O contain the maleate(–2) anion (L′2–), which was formed in situ through metal‐ion‐assisted hydrolysis of the primary amide group of H2L. Efforts to prepare complex 3 from the direct use of maleic acid (H2L′) afforded compounds 4·2nH2O, [Cu4(L′)2(NO3)2(bpy)4(H2O)2](NO3)2·2[Li(NO3)(H2O)3]·4H2O (5·4H2O) and [Cu(NO3)(bpy)(H2O)3](NO3) (6) from the 1:1:1:2 Cu(NO3)·2.5H2O/H2L′/bpy/LiOH·H2O reaction system in MeCN/H2O. The maleamate(–1) ligand presents the less common η1:μ2 coordination mode in the cations of 1, 1·2H2O and 2. The maleate(–2) ligand exhibits the η1:η1:η1:η1:μ3 coordination mode in the [CuII4] cations of 3·2H2O and 5·4H2O and in the [CuII2LiI2] heterometallic cation of 2. The crystal structures of the complexes are stabilized by various H‐bonding patterns. Characteristic IR bands of the complexes are discussed in terms of the known structures and the coordination modes of the ligands. Magnetic susceptibility measurements for 3·2H2O reveal weak ferromagnetic interactions along the periphery of the Cu4 rhombus (J = 3.3 cm–1, –2JijSiSj Hamiltonian formalism), which stabilizes an S = 2 ground state. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
New Bifunctional Substrates for Copper‐Catalyzed Asymmetric Conjugate Addition Reactions with Trialkylaluminium
Authors: Ladjel Chehla , Fuchs Nicolas , Zhao Jinkai , Bernardinelli Gérald , Alexakis Alexandre 
Published: September 2009

AbstractTrialkylaluminium reagents have been found to undergo a copper‐catalyzed asymmetric conjugate addition (ACA) reaction with oxabicyclo[2.2.1]hepta‐2,5‐diene‐2,3‐dicarboxylates with the simultaneous creation of two stereocenters. Different types of ligands were tested, and chiral phosphoramidite ligands allowed the reaction to proceed with good yields and good to excellent enantioselectivity. The syn substitution product observed by X‐ray analysis suggests an exo attack of the nucleophile. Herein we report the results obtained in the development of this copper‐catalyzed ACA methodology, which affords an all‐carbon quaternary center with unsubstituted and substituted oxacyclic Michael acceptors. The study was completed by mechanistic investigations performed to elucidate the original reaction pathway. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)