bluuebunny/crossref_metadata_2025_split huggingface dataset:
Optimization of a miniaturized fluid array device for cell‐free protein synthesis
Authors: Jackson Kirsten , Jin Shouguang , Fan Z. Hugh 
Published: June 2015

ABSTRACTCell‐free protein synthesis (CFPS), which entails synthesizing proteins outside of intact cells, is conducted in several formats with the continuous‐exchange cell‐free (CECF) format generally having the greatest protein expression yields. With this format, continuous chemical exchange occurs through a dialysis membrane separating a reaction solution from a feeding solution containing supplemental nutrient/energy molecules. Here, we describe the optimization of the miniaturized fluid array device (µFAD) by studying the effects of structural and experimental parameters responsible for the heightened chemical exchange across the dialysis membranes and enhanced protein expression capabilities of the high‐throughput device. The interface area and number between the reaction and feeding solutions have a direct impact on protein expression, with a 1.6% enhancement in protein expression yield with each square millimeter increase in area and a 20% decrease with each additional interface. For nutrient/energy availability, an increasing solution volume ratio and height difference increase protein expression yield until the expression yield plateaus at a volume ratio of 20 to 1 (feeding to reaction solution) and a solution height difference of 2 mm. This yield can be further increased by 7% every 30 min with feeding solution replacement. Of the studied experimental factors (feeding solution stirring, device shaking, and temperature increase), feeding solution stirring has a significant effect on protein expression in this device. In the optimized system, green fluorescent protein (GFP), ß‐glucuronidase (GUS), ß‐galactosidase (LacZ), luciferase, and tissue plasminogen activator (tPA) expression increased 77.8‐, 212‐, 3.66‐, 463‐, and 5.43‐fold, respectively, compared to the conventional batch format in a standard microplate. These results highlight the significance of structural/experimental conditions on the productive expression of proteins in the CECF format. Biotechnol. Bioeng. 2015;112: 2459–2467. © 2015 Wiley Periodicals, Inc.
Simultaneous determination of five triterpene acids in rat plasma by liquid chromatography–mass spectrometry and its application in pharmacokinetic study after oral administration of Folium Eriobotryae effective fraction
Authors: Li Zhen‐Hua , Zhu He , Cai Xue‐Ping , He Dan‐Dan , Hua Jun‐Lei , Ju Jian‐Ming , Lv Han , Ma Li , Li Wei‐Lin 
Published: June 2015

AbstractFolium Eriobotryae effective fraction (FEA), the extract of Folium Eriobotryae, had been used as anti‐hyperglycemia and anti‐hyperlipemia medicine in China. A previous study indicated that euscaphic acid, maslinic acid, corosolic acid, oleanolic acid and ursolic acid, the five structurally similar triterpene acids (containing two groups of structural isomers), are the major components of FEA. In the present study, we developed a specific and reliable LC‐MS method for simultaneous determination of the five triterpene acids in rat plasma, and further investigated their pharmacokinetic properties after oral administration of FEA. Following a simple sample preparation, chromatographic separation was achieved on a C18 column with a mobile phase composed of methanol–0.1% ammonium acetate (80:20, v/v). Quantification was achieved by monitoring the selected ions at m/z 487.6 for euscaphic acid, m/z 471.5 for maslinic acid and corosolic acid, m/z 455.5 for oleanolic acid and ursolic acid and m/z 469.5 for internal standard. The method was validated to be specific, accurate and precise over the concentration ranges of 10–3000 ng/mL with limits of detections of 5 ng/mL for the five triterpene acids. Finally, the method was successfully applied to the pharmacokinetic study of the five structurally similar triterpene acids in rats after oral administration of FEA. Copyright © 2015 John Wiley & Sons, Ltd.
Stable isotope dilution HILIC‐MS/MS method for accurate quantification of glutamic acid, glutamine, pyroglutamic acid, GABA and theanine in mouse brain tissues
Authors: Inoue Koichi , Miyazaki Yasuto , Unno Keiko , Min Jun Zhe , Todoroki Kenichiro , Toyo'oka Toshimasa 
Published: June 2015

AbstractIn this study, we developed the stable isotope dilution hydrophilic interaction liquid chromatography with tandem mass spectrometry (HILIC‐MS/MS) technique for the accurate, reasonable and simultaneous quantification of glutamic acid (Glu), glutamine (Gln), pyroglutamic acid (pGlu), γ‐aminobutyric acid (GABA) and theanine in mouse brain tissues. The quantification of these analytes was accomplished using stable isotope internal standards and the HILIC separating mode to fully correct the intramolecular cyclization during the electrospray ionization. It was shown that linear calibrations were available with high coefficients of correlation (r2 > 0.999, range from 10 pmol/mL to 50 nmol/mL). For application of the theanine intake, the determination of Glu, Gln, pGlu, GABA and theanine in the hippocampus and central cortex tissues was performed based on our developed method. In the region of the hippocampus, the concentration levels of Glu and pGlu were significantly reduced during reality‐based theanine intake. Conversely, the concentration level of GABA increased. This result showed that transited theanine has an effect on the metabolic balance of Glu analogs in the hippocampus. Copyright © 2015 John Wiley & Sons, Ltd.
A novel molecularly imprinted method with computational simulation for the affinity isolation and knockout of baicalein from Scutellaria baicalensis
Authors: Li Hong , He Hongliang , Huang Jiaojiao , Wang Chong‐Zhi , Gu Xiaoli , Gao Yankun , Zhang Hongjuan , Du Shuhu , Chen Lina , Yuan Chun‐Su 
Published: June 2015

AbstractA novel molecularly imprinted polymer (MIP) was synthesized by precipitation polymerization with baicalein (BAI) as the template and used as solid‐phase extraction (SPE) adsorbent, aiming at the affinity isolation and selective knockout of BAI from Scutellaria baicalensis Georgi (SB). We used computational simulation to predict the optimal functional monomer, polymerization solvent and molar ratio of template to functional monomer. Characterization and performance tests revealed that MIP exhibited uniform spherical morphology, rapid binding kinetics, and higher adsorption capacity for BAI compared with nonimprinted polymer (NIP). The application of MIP in SPE coupled with high‐performance liquid chromatography to extract BAI from SB showed excellent recovery (94.3%) and purity (97.0%). Not only the single BAI compound, but also the BAI‐removed SB extract was obtained by one‐step process. This new method is useful for isolation and knockout of key bioactive compounds from herbal medicines. Copyright © 2015 John Wiley & Sons, Ltd.
Diazoxide preconditioning of endothelial progenitor cells improves their ability to repair the infarcted myocardium
Authors: Mehmood Azra , Ali Muhammad , Khan Shaheen N. , Riazuddin Sheikh 
Published: June 2015

AbstractReduced survival and homing of the transplanted cells in the oxidative stressed ischemic environment limits the potential outcome of cell therapies for myocardial ischemia. Diazoxide (DZ), a highly selective mitochondrial ATP sensitive K+ channel opener, is known to improve the survival and therapeutic ability of mesenchymal stem cells and skeletal myoblasts for the repair of heart failure. The current study explored the effect of DZ preconditioning in improving the ability of endothelial progenitor cells (EPCs) to counteract, in vitro oxidative stress, and to repair the infarcted myocardium. The EPCs were preconditioned by 30 min incubation with 200 μM DZ followed by exposure to 200 μM hydrogen peroxide (H2O2) for 2 h. Non‐preconditioned EPCs with and without exposure to H2O2 were used as control. DZ preconditioning of EPCs resulted in significantly reduced cell injury as shown by reduced lactate dehydrogenase release and expression of annexin V‐PE in comparison to untreated EPCs. Furthermore, DZ preconditioned EPCs exhibited upregulated expression of prosurvival genes (VEGF, SDF‐1α, PCNA, and Bcl2), improved chemokines release (VEGF, IGF, and SDF‐1α), viability, Akt phosphorylation and tube formation. In vivo experiments involved transplantation of DZ preconditioned and untreated EPCs in the left ventricle after permanent ligation of left anterior descending coronary artery in rats. The results demonstrated that DZ EPCs transplanted group showed significant reduction in infarct size along with robust cell proliferation, angiogenesis and improvement in cardiac function. The current study demonstrates that DZ preconditioning enhances EPCs survival under oxidative stress in vitro and their ability to treat myocardial infarction.
An Investigation of the Effect of the Addition of Tin to 5 %Pd/TiO2 for the Hydrogenation of Furfuryl Alcohol
Authors: King Gavin M. , Iqbal Sarwat , Miedziak Peter J. , Brett Gemma L. , Kondrat Simon A. , Yeo Benjamin R. , Liu Xi , Edwards Jennifer K. , Morgan David J. , Knight David K. , Hutchings Graham J. 
Published: June 2015

AbstractThe selective hydrogenation of furfuryl alcohol was investigated at room temperature by using supported palladium catalysts. The catalysts are very selective to the formation of 2‐methylfuran. Furthermore, the addition of tin to palladium showed similar catalytic activity, but was more selective to tetrahydrofurfuryl alcohol. Variation of the Sn/Pd ratio has shown a considerable and interesting effect on the selectivity pattern. Addition of a small amount of Sn (1 wt %) shifted the selectivity towards tetrahydrofurfuryl alcohol and methyltetrahydrofuran, which are ring‐saturated molecules. Increasing the tin ratio further decreased the catalytic activity and also showed very poor selectivity to either of these products.
Covalent Grafting of Coordination Polymers on Surfaces: The Case of Hybrid Valence Tautomeric Interphases
Authors: González‐Monje Pablo , Novio Fernando , Ruiz‐Molina Daniel 
Published: June 2015

AbstractWe have developed a novel approach for grafting coordination polymers, structured as nanoparticles bearing surface reactive carboxylic groups, to amino‐functionalized surfaces through a simple carbodiimide‐mediated coupling reaction. As a proof‐of‐concept to validate our approach, and on the quest for novel hybrid interphases with potential technological applications, we have used valence tautomeric nanoparticles exhibiting spin transition at or around room temperature. SEM and AFM characterization reveal that the nanoparticles were organized chiefly into a single monolayer while X‐ray photoelectron spectroscopy (XPS) measurements confirm that the nanoparticles retain a temperature‐induced electronic redistribution upon surface anchorage. Our results represent an effective approach towards the challenging manufacture of coordination polymers.
Efficient Hole Extraction from a Hole‐Storage‐Layer‐Stabilized Tantalum Nitride Photoanode for Solar Water Splitting
Authors: Liu Guiji , Fu Ping , Zhou Lingyu , Yan Pengli , Ding Chunmei , Shi Jingying , Li Can 
Published: June 2015

AbstractOne of the major hurdles that impedes the practical application of photoelectrochemical (PEC) water splitting is the lack of stable photoanodes with low onset potentials. Here, we report that the Ni(OH)x/MoO3 bilayer, acting as a hole‐storage layer (HSL), efficiently harvests and stores holes from Ta3N5, resulting in at least 24 h of sustained water oxidation at the otherwise unstable Ta3N5 electrode and inducing a large cathodic shift of ≈600 mV in the onset potential of the Ta3N5 electrode.
Synthesis of Cyclic Carbonates Catalysed by Aluminium Heteroscorpionate Complexes
Authors: Martínez Javier , Castro‐Osma José A. , Earlam Amy , Alonso‐Moreno Carlos , Otero Antonio , Lara‐Sánchez Agustín , North Michael , Rodríguez‐Diéguez Antonio 
Published: June 2015

AbstractNew aluminium scorpionate based complexes have been prepared and used for the synthesis of cyclic carbonates from epoxides and carbon dioxide. Bimetallic aluminium(heteroscorpionate) complexes 9–14 were synthesised in very high yields. The single‐crystal X‐ray structures of 12 and 13 confirm an asymmetric κ2‐NO‐μ‐O arrangement in a dinuclear molecular disposition. These bimetallic aluminium complexes were investigated as catalysts for the synthesis of cyclic carbonates from epoxides and carbon dioxide in the presence of ammonium salts. Under the optimal reaction conditions, complex 9 in combination with tetrabutylammonium bromide acts as a very efficient catalyst system for the conversion of both monosubstituted and internal epoxides into the corresponding cyclic carbonates showing broad substrate scope. Complex 9 and tetrabutylammonium bromide is the second most efficient aluminium‐based catalyst system for the reaction of internal epoxides with carbon dioxide. A kinetic study has been carried out and showed that the reactions were first order in complex 9 and tetrabutylammonium bromide concentrations. Based on the kinetic study, a catalytic cycle is proposed.
Graphene Quantum Dots Assembled with Metalloporphyrins for “Turn on” Sensing of Hydrogen Peroxide and Glucose
Authors: Zhang Li , Peng Dong , Liang Ru‐Ping , Qiu Jian‐Ding 
Published: June 2015

AbstractNoncovalent and multifunctional hybrids have been generated via π–π stacking and electrostatic interactions by combining the nanometer‐scale graphene structure of graphene quantum dots (GQDs) with FeIII 5,10,15,20‐tetrakis(1‐methyl‐4‐pyridyl)porphine (FeTMPyP). The inner filter effect (IFE) of FeTMPyP on the GQDs results in substantial PL quenching of the GQDs. The quenched PL of GQDs by the FeTMPyP can be switched back “on” in response to the reaction between FeTMPyP and H2O2, which causes rupture of the cyclic tetrapyrrolic nucleus with consequential loss of iron from FeTMPyP, and then proceeds further to produce colorless dipyrroles and monopyrroles. This “turn on” system can be applied for simple and convenient H2O2 sensing and can be further extended to the detection of glucose in combination with the specific catalytic effect of glucose oxidase (GOx) through the oxidation of glucose and formation of H2O2. Because of the inherent synthetic control available for the design of metalloporphyrins, the GQDs‐based optical sensing approach described here has the potential to be highly versatile for other target analytes.
A New Strategy for Fluorogenic Esterase Probes Displaying Low Levels of Non‐specific Hydrolysis
Authors: Kim Sungwoo , Kim Hyunjin , Choi Yongdoo , Kim Youngmi 
Published: June 2015

AbstractA new design for fluorescence probes of esterase activity that features a carboxylate‐side pro‐fluorophore is demonstrated with boron dipyrromethene (BODIPY)‐based probes 1 a and 1 b. Because the design relies on the enzyme‐catalyzed hydrolysis of an ester group that is not electronically activated, these probes exhibit a stability to background hydrolysis that is far superior to classical alcohol‐side profluorophore‐based probes, large signal‐to‐noise ratios, reduced sensitivity to pH variations, and high enzymatic reactivity. The utility of probe 1 a was established with a real‐time fluorescence imaging experiment of endogenous esterase activity that does not require washing of the extracellular medium.
Divergent Synthesis of Aeruginosins Based on a C(sp3)H Activation Strategy
Authors: Dailler David , Danoun Grégory , Ourri Benjamin , Baudoin Olivier 
Published: June 2015

AbstractA general and scalable access to the aeruginosin family of marine natural products, exhibiting potent inhibitory activity against serine proteases, is reported. This was enabled by the strategic use of two recently implemented Pd‐catalyzed C(sp3)H activation reactions. The first method allowed us to obtain the common 2‐carboxy‐6‐hydroxyoctahydroindole (Choi) core of the target molecules on a large scale, whereas the second method provided a rapid and divergent access to various hydroxyphenyllactic (Hpla) subunits, including halogenated ones. This unique strategy, together with an optimization of the fragment coupling sequence allowed the synthesis of four aeruginosins, that is, 98A–C and 298A from the chiral pool. Among them, aeruginosin 298A was synthesized on an unprecedentedly large scale. In addition, halogenated aeruginosins 98A and 98C were synthesized for the first time, thanks to a fine‐tuning of the final hydrogenation step.
Stimuli‐Responsive Frustrated Lewis‐Pair‐Type Reactivity of a Tungsten Iminoazaphosphiridine Complex
Authors: Villalba Franco José Manuel , Schnakenburg Gregor , Sasamori Takahiro , Espinosa Ferao Arturo , Streubel Rainer 
Published: June 2015

AbstractReactions of 3‐imino‐azaphosphiridine complexes 1 a,b with carbodiimides 2 a,b, isocyanates 3 a,b, and carbon dioxide are described. Whereas exchange of the carbodiimide unit occurs in the first case, an overall ring expansion takes place with phenyl isocyanate (3 a) and carbon dioxide to yield complexes 4 and 5 bearing novel 1,3,5‐oxazaphospholane ligands; the isopropyl derivative 3 b did not react under these conditions. DFT calculations provide insight into the pathway of the reaction with carbon dioxide with model complex 1 c, revealing effects of initial non‐covalent interactions with the substrate onto the ring bonding, thus triggering an initially masked frustrated Lewis‐pair‐type behavior.
Evaluation of Tetrahydropalmatine Enantiomers on the Activity of Five Cytochrome P450 Isozymes in Rats Using a Liquid Chromatography / Mass Spectrometric Method and a Cocktail Approach
Authors: Li Wuhong , Zhao Liang , Le Jian , Zhang Yinying , Liu Yinli , Zhang Guoqing , Chai Yifeng , Hong Zhanying 
Published: June 2015

AbstractThe aim was to evaluate the effects of tetrahydropalmatine (THP) enantiomers on the activity of five cytochrome P450 (CYP450) isozymes in vivo. A liquid chromatography / mass spectrometric (LC‐MS) method was developed for simultaneous determination of five specific probe substrates including metoprolol (2D6), caffeine (1A2), dapsone (3A4), chlorzoxazone (2E1), and tolbutamide (2C9) in rat plasma. Analytes were separated with the mobile phase consisting of 0.1% acetic acid aqueous solution and acetonitrile in a gradient elution. The mass spectrometric detection via selected ion monitoring (SIM) was operated in both positive ion mode (for metoprolol m/z 268, caffeine m/z 195, and dapsone m/z 249) and negative ion mode (for chlorzoxazone m/z 168 and tolbutamide m/z 269) in the same run. Linear correlation was obtained (r2 > 0.99) over the concentration range of 0.050–25.0 µg/mL for caffeine and dapsone, 0.025–10.0 µg/mL for metoprolol, 0.050–50.0 µg/mL for chlorzoxazone, and 0.25–100.0 µg/mL for tolbutamide. Intra‐ and interday precision were less than 12.09%. The matrix effect ranged from 87.50% to 109.25% and the absolute recoveries were greater than 70%. The method was successfully applied to evaluate the effect of THP enantiomers on the activity of CYP450 isozymes by a cocktail approach. The pharmacokinetic results of five probe drugs indicated that there were stereoselective differences between the two THP enantiomers, i.e., d‐THP had the potential to inhibit the activities of CYP2D6 and CYP1A2 isozymes, while l‐THP inhibited CYP1A2 isozyme and induced CYP3A4 and CYP2C9 isozymes. Chirality 27:551–556, 2015. © 2015 Wiley Periodicals, Inc.
An optimization‐based method for prediction of lumbar spine segmental kinematics from the measurements of thorax and pelvic kinematics
Authors: Shojaei I. , Arjmand N. , Bazrgari B. 
Published: June 2015

SummaryGiven measurement difficulties, earlier modeling studies have often used some constant ratios to predict lumbar segmental kinematics from measurements of total lumbar kinematics. Recent imaging studies suggested distribution of lumbar kinematics across its vertebrae changes with trunk rotation, lumbar posture, and presence of load. An optimization‐based method is presented and validated in this study to predict segmental kinematics from measured total lumbar kinematics. Specifically, a kinematics‐driven biomechanical model of the spine is used in a heuristic optimization procedure to obtain a set of segmental kinematics that, when prescribed to the model, were associated with the minimum value for the sum of squared predicted muscle stresses across all the lower back muscles. Furthermore, spinal loads estimated using the predicted kinematics by the present method were compared with those estimated using constant ratios. Predicted segmental kinematics were in good agreement with those obtained by imaging with an average error of ~10%. Compared with those obtained using constant ratios, predicted spinal loads using segmental kinematics obtained here were in general smaller. In conclusion, the proposed method offers an alternative tool for improving model‐based estimates of spinal loads where image‐based measurement of lumbar kinematics is not feasible. Copyright © 2015 John Wiley & Sons, Ltd.
Influence of bedrock groundwater on streamflow characteristics in a volcanic catchment
Authors: Fujimoto Masamitsu , Ohte Nobuhito , Kawasaki Masatoshi , Osaka Ken'ichi , Itoh Masayuki , Ohtsuka Izumi , Itoh Masami 
Published: June 2015

AbstractGroundwater movements in volcanic mountains and their effects on streamflow discharge and representative elementary area (REA) have remained largely unclear. We surveyed the discharge and chemical composition of spring and stream water in two catchments: the Hontani river (NR) catchment (6.6 km2) and the Hosotani river (SR) catchment (4.0 km2) at the southern part of Daisen volcano, Japan. Daisen volcano is a young volcano (17 × 103 years) at an early stage of erosion. Our study indicated that deep groundwater that moved through thick lava and pyroclastic flows and that could not be explained by shallow movements controlled by surface topography contributed dominantly to streamflow at larger catchment areas. At the NR catchment, the deep groundwater contribution clearly increased at a catchment boundary defined by an area of 3.0 km2 and an elevation of 800 m. At the SR catchment, the contribution deep groundwater to the stream also increased suddenly at a boundary threshold of 2.0 and 700 m. Beyond these thresholds, the contributions of deep bedrock groundwater remained constant, indicating that the REA is between 2 and 3 km2 at the observed area. These results indicate that the hydrological conditions of base flow were controlled mainly by the deep bedrock groundwater that moved through thick lava and pyroclastic flows in the undissected volcanic body of the upper part of the catchment. Our study demonstrates that deep and long groundwater movements via a deep bedrock layer including thick deposits of volcanic materials at the two catchments on Daisen volcano strongly determined streamflow discharge instead of the mixing of small‐scale hydrological conditions. Copyright © 2015 John Wiley & Sons, Ltd.