bluuebunny/crossref_metadata_2025_split huggingface dataset:
Randomized clinical trial of anal fistula plugversusendorectal advancement flap for the treatment of high cryptoglandular fistulain ano
Authors: Ortiz H , Marzo J , Ciga M A , Oteiza F , Armendáriz P , de Miguel M 
Published: April 2009

AbstractBackgroundThe aim of this randomized study was to compare the results of anal fistula plug and endorectal advancement flap in the treatment of high fistula in ano of cryptoglandular origin.MethodsConsecutive patients with high trans-sphincteric fistula in ano of cryptoglandular aetiology were randomized to treatment with either an anal fistula plug or endorectal advancement flap. Patients agreed to participate in a follow-up programme, which included scheduled visits at 2, 4, 8, 12 and 24 weeks and at 1 year after surgery. The primary endpoint was effectiveness in fistula healing. Recurrence was defined as the presence of an abscess arising in the same area, or obvious evidence of fistulation.ResultsA large number of recurrences in the fistula plug group led to premature closure of the trial. After 1 year, fistula recurrence was noted in 12 of 15 patients treated with an anal fistula plug compared with two of 16 treated with an endorectal advancement flap (relative risk 6·40 (95 per cent confidence interval 1·70 to 23·97); P &lt; 0·001).ConclusionContrary to other published studies, an anal fistula plug was associated with a low rate of fistula healing, particularly in patients with a history of fistula surgery.
Quantitative separation of oxytocin, norfloxacin and diclofenac sodium in milk samples using capillary electrophoresis
Authors: Solangi Amber R. , Memon Saima Q. , Mallah Arfana , Khuhawar M. Y. , Bhanger M. I. 
Published: April 2009

AbstractA simple, sensitive and rapid method has been developed for simultaneous separation and quantification of three different drugs: oxytocin (OT), norfloxacin (NOR) and diclofenac (DIC) sodium in milk samples using capillary electrophoresis (CE) with UV detection at 220 nm. Factors affecting the separation were pH, concentration of buffer and applied voltage. Separation was obtained in less than 9 min with sodium tetraborate buffer of pH 10.0 and applied voltage 30 kV. The separation was carried out from uncoated fused silica capillary with effective length of 50 cm with 75 µm i.d. The carrier electrolyte gave reproducible separation with calibration plots linear over 0.15–4.0 µg/mL for OT, 5–1000 µg/mL for NOR and 3–125 µg/mL for DIC. The lower limits of detection (LOD) were found to be 50 ng/mL for OT, and 1 µg/mL for NOR and DIC. The method was validated for the analysis of drugs in milk samples and pharmaceutical preparations with recovery of drugs within the range 96–100% with RSD 0.9–2.8%. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of hydroxyl radical‐induced oxidation process of glucagon by reversed‐phase HPLC and ESI‐MS/MS
Authors: Ichiba Hideaki , Ogawa Tomoko , Yajima Takehiko , Fukushima Takeshi 
Published: April 2009

AbstractStructural modification of a polypeptide hormone, glucagon, by a hydroxyl radical in vitro was investigated by reversed‐phase high‐performance liquid chromatography (RP‐HPLC), and the oxidized site of glucagon was detected by electrospray ionization tandem mass spectrometry (ESI‐MS/MS). It was shown that 27methionine (Met) was oxidized to 27Met sulfoxide by hydroxyl radical, and the production rate of 27Met sulfoxide was faster than that by hydrogen peroxide. In addition, production of 27Met sulfoxide enantiomer was confirmed by RP‐HPLC analysis. cAMP production in a HepG2 cell induced by 27Met sulfoxide glucagon was reduced to approximately 75% as compared with that induced by the native form of glucagon. Copyright © 2009 John Wiley & Sons, Ltd.
Development and reproducibility of a novel high‐performance liquid‐chromatography monolithic column method for the detection and quantification of trans‐indolyl‐3‐acryloylglycine in human urine
Authors: Carr Kevin , Whiteley Paul , Shattock Paul 
Published: April 2009

AbstractElevated levels of trans‐indolyl‐3‐acryloylglycine (IAcrGly) have been reported in the urine of people with various conditions including pervasive developmental disorders (PDDs) such as autism and Asperger syndrome. Reversed‐phase high‐performance liquid chromatography with ultra‐violet detection using traditional particle silica‐based columns subsequent to solid‐phase extraction (SPE) has been the preferred assay method; requiring long analytical run times, high flow rates and high solvent usage. Recent developments in monolithic HPLC column technology facilitated the development of a novel analytical method, for the detection and quantification of urinary IAcrGly. The revised method eliminates the requirement for SPE pre‐treatment, reduces sample run‐time and decreases solvent volumes. Five urine samples from people diagnosed with PDD were run in quadruplicate to test the intra‐ and inter‐day reliability of the new method based on retention time, peak area and peak height for IAcrGly. Detection was by UV with IAcrGly confirmation by MS/MS‐MS. Relative standard deviations showed significant improvement with the new method for all parameters. The new method represents a major advancement in the detection and quantification of IAcrGly by reducing time and cost of analysis whilst improving detection limits and reproducibility. Copyright © 2009 John Wiley & Sons, Ltd.
On‐column refolding of corticotropin‐releasing factor receptor 1 extracellular domain by size exclusion chromatography
Authors: Ersoy Maria , Matic Sandra , Schmidt Stefan R. 
Published: April 2009

AbstractExpressing the extracellular domain of corticotropin releasing factor receptor 1 in Escherichia coli usually results in the formation of inclusion bodies. Here we describe the optimization of refolding by applying size exclusion chromatography with a denaturing guanidine hydrochloride gradient and a refolding buffer containing glycerol. Several chromatographic parameters like gradient length, flow rate, sample concentration and chromatography resin characteristics were evaluated. Recovery yields of refolded protein above 50% using a Superdex 200 column demonstrate the usefulness of this method. Copyright © 2009 John Wiley & Sons, Ltd.
Association of a new intronic polymorphism of the SOD2 gene (G1677T) with cancer
Authors: Hernandez‐Saavedra Daniel , McCord Joe M. 
Published: April 2009

AbstractThere is growing evidence of the correlation between cancer and reactive oxygen species (ROS), especially superoxide. Low expression levels of the Mn‐superoxide dismutase (SOD2) enzyme have been reported in cancer patients. Genetic variation in the regulatory regions of the SOD2 gene may increase the risk of cancer. We identified a genetic variation (G1677T, rs2Y758Y339) in the vicinity of the enhancer region located in intron 2 of the SOD2 gene that creates a potential glucocorticoid responsive element, and developed an assay to screen DNA samples of 220 individuals (73 control, 59 prostate cancer survival individuals and 88 lung cancer biopsies). There were no significant differences in the genotype frequency distribution among prostate, lung cancer and control (p = 0.074 and 0.057, respectively). However, we identified an association of T allele with a decreased risk of lung cancer (OR = 0.525, p = 0.037). The use of the G1677T polymorphism of SOD2 gene as a genetic risk marker may suggest new approaches for detection, prevention, treatment, and prognosis of cancer. Copyright © 2009 John Wiley & Sons, Ltd.
Design of Triazole‐Tethered Glycoclusters Exhibiting Three Different Spatial Arrangements and Comparative Study of their Affinities towards PA‐IL and RCA 120 by Using a DNA‐Based Glycoarray
Authors: Moni Lisa , Pourceau Gwladys , Zhang Jing , Meyer Albert , Vidal Sébastien , Souteyrand Eliane , Dondoni Alessandro , Morvan François , Chevolot Yann , Vasseur Jean‐Jacques , Marra Alberto 
Published: April 2009

AbstractSugar‐coated chips: Glycoside clusters are valuable tools for carbohydrate–lectin recognition studies. However, the spatial arrangement of the sugar residues is a key issue in the design of high‐affinity glycoclusters. Here the affinities of linear and antenna‐ and calixarene‐based galactoside clusters towards two lectins derived from Pseudomonas aeruginosa and Ricinus communis were compared by means of glycoarrays.magnified imageInteractions between proteins and carbohydrates are involved in a large number of crucial biological events. Many efforts have been devoted to the design and synthesis of unnatural saccharides displaying high affinities towards targeted lectins. Among others, glycoside clusters have proven to be valuable tools for these recognition studies. However, the spatial arrangements of the sugar residues are a key issue in the design of high‐affinity glycoclusters. Here, the affinities of linear and antenna‐ and calixarene‐based galactoside clusters against two lectins, derived from Pseudomonas aeruginosa and Ricinus communis, have been compared by means of glycoarrays.
Parallel Pathways and Free‐Energy Landscapes for Enzymatic Hydride Transfer Probed by Hydrostatic Pressure
Authors: Pudney Christopher R. , McGrory Tom , Lafite Pierre , Pang Jiayun , Hay Sam , Leys David , Sutcliffe Michael J. , Scrutton Nigel S. 
Published: April 2009

AbstractMutation of an active‐site residue in morphinone reductase leads to a conformationally rich landscape that enhances the rate of hydride transfer from NADH to FMN at standard pressure (1 bar). Increasing the pressure causes interconversion between different conformational substates in the mutant enzyme. While high pressure reduces the donor–acceptor distance in the wild‐type enzyme, increased conformational freedom “dampens” its effect in the mutant.magnified imageWe show that hydride transfer from NADH to FMN catalysed by the N189A mutant of morphinone reductase occurs along parallel “chemical” pathways in a conformationally rich free‐energy landscape. We have developed experimental kinetic and spectroscopic tools by using hydrostatic pressure to explore this free‐energy landscape. The crystal structure of the N189A mutant enzyme in complex with the unreactive coenzyme analogue NADH4 indicates that the nicotinamide moiety of the analogue is conformationally less restrained than the corresponding structure of the wild‐type NADH4 complex. This increased degree of conformational freedom in the N189A enzyme gives rise to the concept of multiple reactive configurations (MRCs), and we show that the relative population of these states across the free‐energy landscape can be perturbed experimentally as a function of pressure. Specifically, the amplitudes of individual kinetic phases that were observed in stopped‐flow studies of the hydride transfer reaction are sensitive to pressure; this indicates that pressure drives an altered distribution across the energy landscape. We show by absorbance spectroscopy that the loss of charge‐transfer character of the enzyme–coenzyme complex is attributed to the altered population of MRCs on the landscape. The existence of a conformationally rich landscape in the N189A mutant is supported by molecular dynamics simulations at low and high pressure. The work provides firm experimental and computational support for the existence of parallel pathways arising from multiple conformational states of the enzyme–coenzyme complex. Hydrostatic pressure is a powerful and general probe of multidimensional energy landscapes that can be used to analyse experimentally parallel pathways for enzyme‐catalysed reactions. We suggest that this is especially the case following directed mutation of a protein, which can lead to increased population of reactant states that are essentially inaccessible in the free‐energy landscape of wild‐type enzyme.
The Folly of Protobranching: Turning Repulsive Interactions into Attractive Ones and Rewriting the Strain/Stabilization Energies of Organic Chemistry
Authors: Gronert Scott 
Published: April 2009

AbstractStrain/stabilization energies: Recently it has been argued that the accepted strain/stabilization energies of fundamental species are incorrect because they ignore the effects of protobranching. Here it is shown that the basic premise of the protobranching mechanism is unlikely and that conventional strain/stabilization energies are more chemically important than those from the protobranching approach.magnified image
Controlling the Formation of Cyanine Dye H‐ and J‐Aggregates with Cucurbituril Hosts in the Presence of Anionic Polyelectrolytes
Authors: Gadde Suresh , Batchelor Elizabeth K. , Kaifer Angel E. 
Published: April 2009

AbstractControlling aggregation: The formation of H‐ and J‐aggregates by cyanine dyes can be significantly enhanced by poly(styrenesulfonate) and further controlled though host–guest complexation with the cucurbit[7]uril host (see picture).magnified imageThe presence of anionic polyelectrolytes enhances the tendency of cationic cyanine dyes to form aggregates in aqueous media. In this work we investigate the interactions between two cyanine dyes, pseudoisocyanine (PIC) and pinacyanol (PIN), with polystyrenesulfonate (PSS) as the key additive to develop J‐ and H‐aggregates. We also take advantage of the binding properties of the cucurbit[7]uril (CB7) host to control formation of these aggregates through its host–guest interactions with the dye molecules. UV/Vis absorption spectroscopic studies clearly demonstrate the PSS‐enhanced formation of J‐aggregates in the case of PIC and H‐aggregates in the case of PIN. Electrostatic interactions between the cyanine dye molecules and the polyelectrolyte chains assist the formation of J‐ or H‐aggregates at very low dye concentrations (ca. 10 μM). Optimum development of dye aggregates was observed at a sulfonate/dye molar ratio of about 3:1. Departures from this stoichiometric ratio seem to perturb the optimal aggregate structure. Furthermore, the presence of CB7 was found to effectively disrupt the interactions responsible for dye aggregation. Thus, CB7 completely disrupts the J‐aggregates formed by PIC and the H‐aggregates (as well as lower concentrations of J‐aggregates) formed by PIN. UV/Vis and emission spectroscopic studies clearly indicate that binding of CB7 to both dye molecules removes them from the aggregate structures. Our spectroscopic data clearly indicate that regulation of the relative molar ratios of dye, CB7 host, and polyelectrolyte sulfonate groups leads to a quantitative control of dye aggregation, yielding variable amounts of PIC J‐ and PIN H‐aggregates in these solutions.
The Laulimalide Family: Total Synthesis and Biological Evaluation of Neolaulimalide, Isolaulimalide, Laulimalide and a Nonnatural Analogue
Authors: Gollner Andreas , Altmann Karl‐Heinz , Gertsch Jürg , Mulzer Johann 
Published: April 2009

AbstractA sensitive family: The first total synthesis of the antitumor agents neolaulimalide and isolaulimalide as well as a highly efficient route to laulimalide is described. A Kulinkovich reaction followed by a cyclopropyl–allyl rearrangement is used to install the exo‐methylene group. The cytotoxicity of neolaulimalide could be confirmed for the first time since its original isolation and it could be shown that it induces tubulin polymerization as efficiently as laulimalide.magnified imageWe herein describe in full detail the first total synthesis of the antitumor agents neolaulimalide and isolaulimalide as well as a highly efficient route to laulimalide. A Kulinkovich reaction followed by a cyclopropyl–allyl rearrangement is used to install the exo‐methylene group. The C2–C16 aldehyde fragment is coupled with the C17–C28 sulfone fragments by a highly (E)‐selective Julia–Lythgoe–Kocienski olefination to deliver the key intermediates of all three syntheses. Various conditions for the Yamaguchi macrolactonization are applied to close the individual macrocycles. Finally a carefully elaborated endgame was developed to solve the problem of acyl migration in the case of neolaulimalide. All compounds were tested against several cell lines. The cytotoxicity of neolaulimalide could be confirmed for the first time since its original isolation and it could be shown that it induces tubulin polymerization as efficiently as laulimalide.
Catalytic Asymmetric Baeyer–Villiger Oxidation in Water by Using PtII Catalysts and Hydrogen Peroxide: Supramolecular Control of Enantioselectivity
Authors: Cavarzan Alessandra , Bianchini Giulio , Sgarbossa Paolo , Lefort Laurent , Gladiali Serafino , Scarso Alessandro , Strukul Giorgio 
Published: April 2009

AbstractThe enantioselective Baeyer–Villiger oxidation of cyclic ketones is a challenging reaction, especially when using environmentally friendly oxidants. The reaction was carried out in water by using soft Lewis acid PtII complexes that have chiral diphosphines as well as monophosphines. Addition of a surfactant is crucial, which leads to the formation of micelles that act as nanoreactors in which the substrate and catalyst encounter each other in an ordered medium that in several cases positively influences both the conversion and the selectivity of the reactions. This is due to the combination of the hydrophobic effect (which confines the components of the reaction in the micelles), together with supramolecular interactions between the partners within the ordered palisade provided by the alkyl chains of the surfactant. For the oxidation of meso‐cyclobutanones, addition of surfactant allowed the reaction to proceed in high yields and the enantiometic excess (ee; 56 %) was higher than in organic solvents. Subsequent extension to meso‐cyclohexanones resulted in a general decrease in yields but an enhancement of enantioselectivity (ee up to 92 %) moving from organic to water–surfactant media, regardless of the substrate or the catalyst employed. Different behaviour was observed with chiral cyclobutanones 7 and 10: with 7 the best catalyst was 1 g, whereas with the larger substrate, 10, complexes 1 a–b performed better in terms of enantioselectivity. Each combination of substrate, catalyst and surfactant is a new system and supramolecular reciprocal interactions together with the hydrophobic character of the counterparts play crucial roles. The asymmetric Baeyer–Villiger oxidation in water catalyzed by 1 a–h in the presence of micelles is a viable reaction that often benefits from the hydrophobic effect, leading to substantial increases in enantioselectivity.
Low‐Molecular‐Weight Dendrons for DNA Binding and Release by Reduction‐Triggered Degradation of Multivalent Interactions
Authors: Kostiainen Mauri A. , Rosilo Henna 
Published: April 2009

AbstractLosing the grip: The synthesis of multivalent low‐molecular‐weight dendrons with lysine branching units coupled to disulfide‐linked spermine surface groups is described. It is furthermore demonstrated that the dendrons bind DNA with good affinity (see image), but are also able to release the DNA in a reductive environment.magnified image
Exploring adoption difficulties in mobile banking services
Authors: Yang Ann Shawing 
Published: April 2009

AbstractFactors associated with adopting and resisting mobile banking technologies were investigated among university students in Taiwan. Adoption factors included the belief that mobile banking helps fulfill personal banking needs, provides location‐free conveniences, and is cost effective. The primary factors associated with resistance included concerns over system configuration security and basic fees for mobile banking web connections. The theoretical and applied implications of these findings are discussed. Copyright © 2009 ASAC. Published by John Wiley & Sons, Ltd.
Centriole assembly in CHO cells expressing Plk4/SAS6/SAS4 is similar to centriogenesis in ciliated epithelial cells
Authors: Kuriyama Ryoko 
Published: April 2009

AbstractCentriole assembly is initiated by Plk4, a Polo‐like kinase 4, which causes the recruitment of downstream regulators, such as SAS6 and SAS4, to a nascent centriole. Simultaneous expression of Plk4, SAS6 and SAS4 in CHO cells resulted in the formation of massive fibrogranular aggregates of various sizes and shapes. These aggregates were surrounded by dense particles of about 70 nm in diameter, similar to the centriolar satellite that has been observed around the centrosome in normal cycling cells. Within the fibrillar material, ring‐like structures appeared and eventually differentiated into centrioles by association with short microtubule bundles. Centrioles were also assembled around a parent centriole in a cluster, a configuration that has been described as a “flower structure” formation [Kleylein‐Sohn et al.,2007]. This pattern of centriole duplication is reminiscent of the arrangement of new centrioles induced in normal ciliated trachea/oviduct cells by the centriole‐dependent pathway, which was reported several decades ago [Sorokin,1968; Anderson and Brenner,1971; Dirksen,1971]. Prior to the production of hundreds of centrioles, these differentiating epithelial cells were also shown to induce a dense filamentous material similar to that detected in transfected CHO cells. These results suggest a common mechanism of centriole assembly regulated by Plk4 in both transfected cycling cells and normal ciliated epithelial cells undergoing differentiation. Cell Motil. Cytoskeleton 2009. © 2009 Wiley‐Liss, Inc.
Dasatinib early intervention after cytogenetic or hematologic resistance to imatinib in patients with chronic myeloid leukemia
Authors: Quintás‐Cardama Alfonso , Cortes Jorge E. , O'Brien Susan , Ravandi Farhad , Borthakur Gautam , Liu David , Bleickardt Eric , Chen Tai‐Tsang , Kantarjian Hagop M. 
Published: April 2009

AbstractBACKGROUND:Although many patients with chronic myeloid leukemia (CML) respond well to imatinib therapy, a significant proportion loses their initial response. Loss of response on imatinib is often because of BCR‐ABL mutations. Dasatinib is a 325‐fold more potent inhibitor of Bcr‐Abl than imatinib and has been associated with high rates of durable responses in patients with CML in chronic phase (CP) after imatinib failure.METHODS:To determine the optimal time for initiating dasatinib after loss of response on imatinib, data from dasatinib trials in CML‐CP were analyzed. Patients were grouped according to whether they received early intervention with dasatinib (ie, after cytogenetic recurrence on imatinib), rather than after both cytogenetic and hematologic recurrence.RESULTS:Overall, 72% of patients who received dasatinib after loss of a major cytogenetic response (MCyR) on imatinib achieved a complete cytogenetic response (CCyR) compared with 42% of patients who were treated after loss of both MCyR and complete hematologic response (CHR). Event‐free survival (EFS) also was higher after earlier dasatinib treatment (24‐month EFS rates: 89% after loss of MCyR on imatinib vs 29% after loss of both MCyR and CHR). Among patients who were treated after loss of CHR on imatinib with no prior MCyR, 26% achieved a CCyR with dasatinib, and the 24‐month EFS rate was 64%. In all 3 groups, CCyR rates were similar in patients with or without pre‐existing BCR‐ABL mutations.CONCLUSIONS:The results of the current study suggested that optimal outcomes are achieved when dasatinib is administered early after imatinib resistance. Cancer 2009. © 2009 American Cancer Society.