bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characterization of the proteases involved in the N‐terminal clipping of glucagon‐like‐peptide‐1‐antibody fusion proteins
Authors: Dorai Haimanti , Santiago Aleixo , Campbell Marguerite , Tang Q. Mike , Lewis Michael J. , Wang Yonghui , Lu Qiao‐Zhen , Wu Shiaw‐Lin , Hancock William 
Published: November 2010

AbstractIn an attempt to develop high producing mammalian cell lines expressing glucagon‐like‐peptide‐1‐antibody fusion proteins (GLP‐1), we have noted that the N‐terminal GLP‐1 portion of the fusion protein was susceptible to proteolytic degradation during cell culture, which resulted in an inactive product. The majority of the N‐terminal clipped product appeared to be due to the removal of the entire biologically active peptide (30 amino acids) from the intact molecule. A number of parameters that influenced the degradative process were investigated. Additionally, protease inhibitors specific for each class of protease were tested. Results suggested that one or more serine‐threonine class of protease(s) were involved in this process and inhibitors that are specific for this class of protease, including benzamidine hydrochloride could significantly inhibit the proteolytic degradation of the fusion proteins. Identification of the specific proteases involved in this process by shotgun proteomics methodology will pave the way for engineering the CHOK1SV cell line which will serve as a superior host for the production of future fusion protein products. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
High‐density microcarrier cell cultures for influenza virus production
Authors: Bock A. , Schulze‐Horsel J. , Schwarzer J. , Rapp E. , Genzel Y. , Reichl U. 
Published: November 2010

AbstractInfluenza virus A/PR/8/34 virus propagation in adherent Madin–Darby canine kidney cells in high‐density microcarrier cultures is described. To improve virus yields, perfusion and repeated fed‐batch modes were applied using cell‐specific feed rates. Cell densities up to 1.1 × 107cells/mL were achieved. Cell‐specific virus yields in high‐density cultures were at similar levels compared with standard, low‐density cultivations. In the average 2,400 and 3,300 virions per cell were obtained for two variants of the virus strain A/PR/8/34, PR8‐National Institute for Biological Standards and Control (NIBSC) and PR8‐Robert Koch Institute, respectively. Maximum virus titer (HA activity = 1,778 HAU/100 μL) for virus variant PR8‐NIBSC was obtained for a cultivation infected before maximum cell concentration was reached. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Offline glucose biomonitoring in yeast culture by polyamidoamine/ cysteamine‐modified gold electrodes
Authors: Yuksel Merve , Akin Mehriban , Geyik Caner , Demirkol Dilek Odaci , Ozdemir Caglar , Bluma Arne , Höpfner Tim , Beutel Sascha , Timur Suna , Scheper Thomas 
Published: November 2010

AbstractThis article deals with the use of pyranose oxidase (PyOx) and glucose oxidase (GOx) enzymes in amperometric biosensor design and their application in monitoring fermentation processes with the combination of flow injection analysis (FIA). The amperometric studies were carried out at −0.7 V by following the oxygen consumption due to the enzymatic reactions for both batch and FIA modes. Optimization studies (enzyme amounts and pH) and analytical parameters such as linearity, repeatability, effect of interference, storage, and operational stabilities have been studied. Under optimized conditions, for the PyOx‐based biosensor, linear graph was obtained from 0.025 to 0.5 mM glucose in phosphate buffer (50 mM) at pH 7.0 with the equation of y = 3.358x + 0.028 and R2 = 0.998. Linearity was found to be 0.01–1.0 mM in citrate buffer (50 mM and pH 4.0) with the equation of y = 1.539x + 0.181 and R2 = 0.992 for the GOx biosensor. Finally, these biosensor configurations were further evaluated in a conventional flow injection system. Results from batch experiments provide a guide to design sensitive, stable, and interference‐free biosensors for FIA mode. Biosensor stability, dynamic range, and repeatability were also studied in FIA conditions, and the applicability for the determination of glucose in fermentation medium could be successfully demonstrated. The FIA‐combined glucose biosensor was used for the offline monitoring of yeast fermentation. The obtained results correlated well with HPLC measurements. © 2011 American Institute of Chemical Engineers Biotechnol. Prog., 2011
Virtual radiation detection and measurement laboratory
Authors: Tiftikci Ali , Kocar Cemil 
Published: November 2010

AbstractSimulation of alpha, beta and gamma radiation detection and measurement experiments which are part of nuclear physics laboratory courses was realized with Monte‐Carlo method and JAVA Programming Language. As it is well known, establishing this type of laboratory is very expensive. At the same time, highly radioactive sources used in some experiments carry risks for students and also for experimentalists. By taking into consideration these problems, the aim of this study is to setup a virtual radiation laboratory with minimum cost and to speed up the training in radiation physics for students. Bearing in mind the training capabilities of the software is coded to allow the users creating their own experimental setup and searching for experimental setup suitable for a specific type of experiment. As an example, mixed source isotope identification with high purity germanium, bismuth germanate, and sodium iodine detectors is studied in this paper and the importance of energy resolution of a detector in such an experiment is discussed. Software shows the nature of radiation and radiation transport with the help of Monte‐Carlo method. In this software, experimental parameters can be changed manually by the user and experimental results can be followed in an multi channel analyzer (MCA) or an single channel analyzer (SCA). Results obtained in experiments can be analyzed by these MCA or SCA panels. Virtual radiation laboratory which is developed in this study with reliable results and unlimited experimentation capability seems a useful educational tool. © 2010 Wiley Periodicals, Inc. Comput Appl Eng Educ 21: 550–560, 2013
Cytotoxic Sesquiterpenes from Magnolia kachirachirai
Authors: Chang Hsun‐Shuo , Lee Shiow‐Ju , Yang Cheng‐Wei , Chen Ih‐Sheng 
Published: November 2010

AbstractBioassay‐guided fractionation of the root wood of Magnolia kachirachirai (Kanehira & Yamamoto) Dandy (Magnoliaceae) led to the isolation of three new compounds, kachiraterpenol (1), (E)‐2,3‐bis(4‐hydroxy‐3‐methoxyphenyl)prop‐2‐enal (15), and kachiranol (19), together with 27 known compounds, of which 4,4′‐dihydroxy‐3,3′‐dimethoxybenzophenone (16) was isolated for the first time from a natural source. Their structures were elucidated by spectroscopic analysis. Two of these isolates, costunolide (2) and dehydrosaussurea lactone (4), showed cytotoxic properties against MCF‐7, NCI‐H460, and SF‐268 cancer cell lines in vitro.
Linking Chemical and Microbial Diversity in Marine Sponges: Possible Role for Poribacteria as Producers of Methyl‐Branched Fatty Acids
Authors: Hochmuth Thomas , Niederkrüger Holger , Gernert Christine , Siegl Alexander , Taudien Stefan , Platzer Matthias , Crews Phillip , Hentschel Ute , Piel Jörn 
Published: November 2010

AbstractMany marine sponges contain massive numbers of largely uncultivated, phylogenetically diverse bacteria that seem to be important contributors to the chemistry of these animals. Insights into the diversity, origin, distribution, and function of their metabolic gene communities are crucial to dissect the chemical ecology and biotechnological potential of sponge symbionts. This study reveals a sharp dichotomy between high and low microbial abundance sponges with respect to polyketide synthase (PKS) gene content, the presence of methyl‐branched fatty acids, and the presence of members of the symbiotic candidate phylum “Poribacteria”. For the symbiont‐rich sponge Cacospongia mycofijiensis, a source of the tubulin‐inhibiting fijianolides (=laulimalides), near‐exhaustive large‐scale sequencing of PKS gene‐derived PCR amplicons was conducted. Although these amplicons exhibit high diversity at the sequence level, almost all of them belong to a single, architecturally unique group of PKSs present in “Poribacteria” and are proposed to synthesize methyl‐branched fatty acids. Three components of this PKS were studied in vitro, providing initial insight into its biochemistry.
Structural Characteristics, Stability, and Activity of (VO)2P2O7 and VO(PO3)2 Catalysts in p‐Cymene Liquid‐Phase Oxidation
Authors: Makgwane Peter R. , Ferg Ernst E. , Zeelie Ben 
Published: November 2010

AbstractThe post‐reaction structural characteristics of VO(PO3)2 and (VO)2P2O7 catalysts and their reusability in liquid‐phase oxidation of p‐cymene to tertiary cymene hydroperoxide (TCHP) are investigated and characterized. The VO(PO3)2 structure remains unchanged after being used for extended reaction times, whereas (VO)2P2O7 undergoes structural changes back to its precursor phase, VOHPO4⋅0.5 H2O, that affect its catalytic properties. The structure of the (VO)2P2O7 that has undergone phase changes is successfully restored by calcination under N2 flow at 750 °C for 2 h. Fresh and used catalysts show different particle morphologies, indicating that the reaction medium influences the microstructure. Both catalysts show considerable reusability with (VO)2P2O7 showing slight gradual deactivation. Taking into account the characterization and catalytic results obtained, the slight (VO)2P2O7 deactivation can probably be ascribed to the adsorption of organic compounds on the catalyst surface, which appears to initiate structural transformation of the (VO)2P2O7 catalyst under oxidation reaction conditions for extended reaction times. The VO(PO3)2 and (VO)2P2O7 catalysts showed to be effective for synthesis of the industrially important intermediate TCHP, a precursor to p‐cresol in liquid‐phase oxidation reactions.
Luminescent Porous Silica Fibers as Drug Carriers
Authors: Hou Zhiyao , Zhang Cuimiao , Li Chunxia , Xu Zhenhe , Cheng Ziyong , Li Guogang , Wang Wenxin , Peng Chong , Lin Jun 
Published: November 2010

AbstractLuminescent and porous silica fibers have been successfully prepared by using the electrospinning process. The obtained multifunctional silica fibers, which possess a porous structure and display blue luminescence, can serve as a drug delivery host carrier, using ibuprofen (IBU) as a model drug, allowing the investigation of storage/release properties. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FT‐IR), N2 adsorption/desorption, photoluminescence (PL) spectra, and kinetic decay were used to characterize the structural, morphological, and optical properties of the as‐obtained samples. The results reveal that the multifunctional silica materials exhibit an irregular porous structure, and display a fiberlike morphology with dimensions of several hundred nanometers in width and several millimeters in length. The obtained silica fibers exhibit an intense broad bluish emission, which might be attributed to impurities and/or defects in the silica fibers. The IBU‐loaded silica fiber system shows blue luminescence under UV irradiation and controlled release behavior for IBU. In addition, the emission intensities of silica fibers in the drug carrier system vary with the released amount of IBU, thus allowing the drug release to be easily tracked and monitored by the change of the luminescence intensity.
Magnetic Electrochemiluminescent Fe3O4/CdSe–CdS Nanoparticle/Polyelectrolyte Nanocomposite for Highly Efficient Immunosensing of a Cancer Biomarker
Authors: Jie Guifen , Wang Lei , Zhang Shusheng 
Published: November 2010

AbstractMagnetic electrochemiluminescent Fe3O4/CdSe–CdS nanoparticle/polyelectrolyte nanostructures have been synthesized and used to fabricate an electrochemiluminescence (ECL) immunosensor for the detection of carcinoembryonic antigen (CEA). CEA is a protein used as a biomarker for several cancers; particularly, to monitor response to treatment in colon and rectal cancer patients. The nanocomposites can be easily separated and firmly attached to an electrode owing to their excellent magnetic properties. This represents a promising advantage for bioassay applications. More importantly, the nanostructures exhibit intense and stable ECL emissions in neutral solution, which makes them ideal for ECL immunosensing. The 3‐aminopropyltriethoxysilane (APS) polyelectrolyte shell on the nanostructure surface not only enhances the intensity and stability of the ECL signal, but also acts as a crosslinker for immunosensor fabrication. A CEA antibody immobilized onto a nanocomposite/APS/electrode with gold nanoparticles comprises the ECL immunosensor. The principle of ECL detection for CEA is based on a change in steric hindrance after immunoreaction, which leads to a decrease in ECL intensity. A wide detection range (0.064 pg ml−1–10 ng ml−1) and low detection limit (0.032 pg ml−1) are achieved. The immunosensor is highly sensitive and selective, and exhibits excellent stability and good reproducibility. It thus has great potential for clinical protein detection. In particular, this approach uses a novel class of bifunctional nanocomposites that display both intense ECL and excellent magnetism, which renders them suitable for a large range of bioassay applications.
Mechanistic Insight into the Reactivity of Oxotransferases by Novel Asymmetric Dioxomolybdenum(VI) Model Complexes
Authors: Mayilmurugan Ramasamy , Harum Bastian N. , Volpe Manuel , Sax Alexander F. , Palaniandavar Mallayan , Mösch‐Zanetti Nadia C. 
Published: November 2010

AbstractThe asymmetric molybdenum(VI) dioxo complexes of the bis(phenolate) ligands 1,4‐bis(2‐hydroxybenzyl)‐1,4‐diazepane, 1,4‐bis(2‐hydroxy‐4‐methylbenzyl)‐1,4‐diazepane, 1,4‐bis(2‐hydroxy‐3,5‐dimethylbenzyl)‐1,4‐diazepane, 1,4‐bis(2‐hydroxy‐3,5‐di‐tert‐butylbenzyl)‐1,4‐diazepane, 1,4‐bis(2‐hydroxy‐4‐flurobenzyl)‐1,4‐diazepane, and 1,4‐bis(2‐hydroxy‐4‐chlorobenzyl)‐1,4‐diazepane (H2(L1)–H2(L6), respectively) have been isolated and studied as functional models for molybdenum oxotransferase enzymes. These complexes have been characterized as asymmetric complexes of type [MoO2(L)] 1–6 by using NMR spectroscopy, mass spectrometry, elemental analysis, and electrochemical methods. The molecular structures of [MoO2(L)] 1–4 have been successfully determined by single‐crystal X‐ray diffraction analyses, which show them to exhibit a distorted octahedral coordination geometry around molybdenum(VI) in an asymmetrical cis‐β configuration. The MoOoxo bond lengths differ only by ≈0.01 Å. Complexes 1, 2, 5, and 6 exhibit two successive MoVI/MoV (E1/2, −1.141 to −1.848 V) and MoV/MoIV (E1/2, −1.531 to −2.114 V) redox processes. However, only the MoVI/MoV redox couple was observed for 3 and 4, suggesting that the subsequent reduction of the molybdenum(V) species is difficult. Complexes 1, 2, 5, and 6 elicit efficient catalytic oxygen‐atom transfer (OAT) from dimethylsulfoxide (DMSO) to PMe3 at 65 °C at a significantly faster rate than the symmetric molybdenum(VI) complexes of the analogous linear bis(phenolate) ligands known so far to exhibit OAT reactions at a higher temperature (130 °C). However, complexes 3 and 4 fail to perform the OAT reaction from DMSO to PMe3 at 65 °C. DFT/B3LYP calculations on the OAT mechanism reveal a strong trans effect.
Photocontrolled Manipulation of a Microscale Object: A Rotational or Translational Mechanism
Authors: Kausar Abu , Nagano Hiroto , Kuwahara Yutaka , Ogata Tomonari , Kurihara Seiji 
Published: November 2010

AbstractIn this paper the photocontrolled manipulation of solid materials on the surface of a liquid crystalline thin film is described. Three different types of films namely cholesteric liquid crystal (ChLC), compensated nematic liquid crystal (NLC) and nematic LC were used. The rotational and translational manipulation of the microscale solid object was induced by irradiation of light and mode of manipulation (either translational or rotational) was changed by changing the isomer of the azobenzene compound used to make the film. Rotational motion of the object was observed on the ChLC and compensated NLC films containing chirally pure azobenzene compound. The direction of rotational motion was controlled either by changing the optical isomer of the chiral azobenzene or by changing the irradiating light (from ultraviolet to visible). When racemic mixture of the chiral azobenzene compound was used, a translational motion of the object was observed. Even though the direction of the translational motion can be controlled by controlling irradiation position, more facile and precise manipulation of the objects was possible by spatially controlled irradiation of Ar+laser and diode UV laser.
Solvent‐ and Temperature‐Dependent Functionalisation of Enantioenriched Aziridines
Authors: de Ceglie Maria Carolina , Musio Biagia , Affortunato Francesco , Moliterni Anna , Altomare Angela , Florio Saverio , Luisi Renzo 
Published: November 2010

AbstractA highly stereo‐ and regioselective functionalisation of chiral non‐racemic aziridines is reported. By starting from a parent enantioenriched aziridine and finely tuning the reaction conditions, it is possible to address the regio‐ and stereoselectivity of the lithiation/electrophile trapping sequence, thereby allowing the preparation of highly enantioenriched functionalised aziridines. From chiral N‐alkyl trans‐2,3‐diphenylaziridines (S,S)‐1 a,b, two differently configured chiral aziridinyllithiums could be generated (trans‐1 a,b‐Li in toluene and cis‐1 a,b‐Li in THF), thus disclosing a solvent‐dependent reactivity that is useful for the synthesis of chiral tri‐substituted aziridines with different stereochemistry. In contrast, chiral aziridine (S,S)‐1 c showed a temperature‐dependent reactivity to give chiral ortho‐lithiated aziridine 1 c‐ortho‐Li at −78 °C and α‐lithiated aziridine 1 c‐α‐Li at 0 °C. Both lithiated intermediates react with electrophiles to give enantioenriched ortho‐ and α‐functionalised aziridines. The reaction of all the lithiated aziridines with carbonyl compounds furnished useful chiral hydroxyalkylated derivatives, the stereochemistry of which was ascertained by X‐ray and NMR spectroscopic analysis. The usefulness of chiral non‐racemic functionalised aziridines has been demonstrated by reductive ring‐opening reactions furnishing chiral amines that bear quaternary stereogenic centres and chiral 1,2‐, 1,3‐ and 1,5‐aminoalcohols. It is remarkable that the solvent‐dependent reactivity observed with (S,S)‐1 a,b permits the preparation of both the enantiomers of amines (11 and ent‐11) and 1,2‐aminoalcohols (13 and ent‐13) starting from the same parent aziridine. Interestingly, for the first time, a configurationally stable chiral α‐lithiated aziridine (1 c‐α‐Li) has been generated at 0 °C. In addition, ortho‐hydroxyalkylated aziridines have been easily converted into chiral aminoalkyl phthalans, which are useful building blocks in medicinal chemistry.
Color and women hitchhikers' attractiveness: Gentlemen drivers prefer red
Authors: Guéguen* Nicolas 
Published: November 2010

AbstractResearch has shown that with some nonhuman primates, red is associated with greater sexual attractiveness of females. Five female confederates in their early 20s posed as hitchhikers wearing T‐shirts of different colors (black, white, red, blue, green, or yellow). It was found that the women wearing red solicited a higher response in the number of male drivers who stopped to offer a ride. No color effect was found when considering the behavior of female drivers. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2012
Mechanism of Proton Relaxation for Enzyme‐Manipulated, Multicomponent Gold–Magnetic Nanoparticle Chains
Authors: Jaganathan Hamsa , Gieseck Richard L. , Hudson Katherine , Kellogg Michael , Ramaswamy Aneesh K. , Raver Kimberly E. , Smith Tyler , Vacchiano Ashley N. , Wager Andrew , Ivanisevic Albena 
Published: November 2010

AbstractLongitudinal and transverse relaxation times of multicomponent nanoparticle (NP) chains are investigated for their potential use as multifunctional imaging agents in magnetic resonance imaging (MRI). Gold NPs (ca. 5 nm) are arranged linearly along double‐stranded DNA, creating gold NP chains. After cutting gold NP chains with restriction enzymes (EcoRI or BamHI), multicomponent NP chains are formed through a ligation reaction with enzyme‐cut, superparamagnetic NP chains. We evaluate the changes in relaxation times for different constructs of gold–iron oxide NP chains and gold–cobalt iron oxide NP chains using 300 MHz 1H NMR. In addition, the mechanism of proton relaxation for multicomponent NP chains is examined. The results indicate that relaxation times are dependent on the one‐dimensional structure and the amount of superparamagnetic NP chains present in the multicomponent constructs. Multicomponent NP chains arranged on double‐stranded DNA provide a feasible method for fabrication of multifunctional imaging agents that improve relaxation times effectively for MRI applications.
Synthesis and photoluminescence properties of bundle‐like CdS nanostructures assembled by high‐quality nanorods
Authors: Xuan Zongwei , Chao Kun , Lu Lude , Li Guicun 
Published: November 2010

AbstractBundle‐like cadmium sulfide (CdS) nanostructures assembled by high‐quality nanorods have been successfully synthesized on a large scale via a facile solvothermal route in a mixed solvent of ethylenediamine and dodecanethiol. The typical lengths of bundle‐like CdS nanostructures are several tens of micrometers, and the diameters and lengths of CdS nanorods are about 50–70 nm and several micrometers, respectively. The influence of the concentration of dodecanethiol on the morphologies of CdS nanostructures has been investigated carefully. Photoluminescence spectra (PL) of CdS nanostructures reveal that the bundle‐like CdS nanostructures exhibited two fluorescence emission peaks centered at 495nm (2.51 eV) and 522 nm (2.38 eV) as the excitation wavelength is 405 nm. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Catalytic Fast Pyrolysis of Cellulose to Prepare Levoglucosenone Using Sulfated Zirconia
Authors: Wang Zhi , Lu Qiang , Zhu Xi‐Feng , Zhang Ying 
Published: November 2010

AbstractSulfated zirconia was employed as catalyst for fast pyrolysis of cellulose to prepare levoglucosenone (LGO), a very important anhydrosugar for organic synthesis. The yield and the selectivity of LGO were studied in a fixed‐bed reactor at different temperatures and cellulose/catalyst mass ratios. The experiments of catalyst recycling were also carried out. The results displayed that from 290 to 400 °C, the liquid and solid accounted for more than 95 wt % of products, and the higher temperature led to more liquid and less solid products. The introduction of SO42−/ZrO2 could promote cellulose conversion and LGO production. The temperature had a similar effect on the yield and selectivity of LGO at different cellulose/catalyst mass ratios. The maximum yield was obtained at 335 °C. Although the structure of the parent ZrO2 was retained after recycles, which was confirmed by X‐ray diffraction and N2 adsorption–desorption measurements, the activity of SO42−/ZrO2 could only be partially recovered by simply calcination. The catalytic activity decrease could be mainly attributed to SO42− leaching, and the activity could be restored by further impregnation of H2SO4.