bluuebunny/crossref_metadata_2025_split huggingface dataset:
Three‐dimensional tracking and temporal analysis of liposomal transport in live cells using bright‐field imaging
Authors: Tsai Feng‐Ching , Tai Lin‐Ai , Wang Yu‐Jing , Xiao Jian‐Long , Hsu Tsi‐Hsuan , Yang Chung‐Shi , Lee Chau‐Hwang 
Published: October 2010

AbstractGold nanoparticles (AuNPs) confined in liposomes of diameters around 200 nm produce strong scattering signal owing to surface plasmon resonance, and therefore bright‐field optical tracking of the AuNP‐encapsulating liposomes can be conducted in living cells. Using an optical profiling technique called noninterferometric wide‐field optical profilometry and a bright‐field tracking algorithm, the polynomial‐fit Gaussian weight method, we analyze three‐dimensional (3D) motion of such liposomes in living fibroblasts. The positioning accuracy in three dimensions is nearly 20 nm. We tag the liposome membranes with fibroblast growth factor‐1 and reveal the intracellular transportation processes toward or away from the nucleus. On the basis of a temporal analysis of the intracellular 3D trajectories of AuNP‐encapsulating liposomes, we identify directed and diffusive motions in the transportation processes. Microsc. Res. Tech., 2010. © 2010 Wiley‐Liss, Inc.
Seasonal flexibility in organ size in the Andean lizard Liolaemus moradoensis
Authors: Naya Daniel E. , Veloso Claudio , Sabat Pablo , Bozinovic Francisco 
Published: October 2010

AbstractThe understanding of animal functioning in fluctuating environments is a major goal of physiological and evolutionary ecology. In temperate terrestrial habitats, one of the most pervasive changes in environmental conditions is that associated with the seasonal change along the year. In this study, we describe the pattern of seasonal variation in the size of nine internal organs in the lizard Liolaemus moradoensis from the Andes Mountains of Central Chile. We observed that the size of digestive organs was greater during summer in comparison to other seasons. Dry masses of liver and fat bodies reached maximum values during summer and minimum during spring. We suspect that lowest spring values are related with build‐up costs of energetically expensive organs (e.g., digestive, muscle mass) at the end of the hibernation period. Dry mass of the heart and lungs did not show a clear pattern of variation, suggesting that cardiac and pulmonary performance were maintained throughout the year. The dry mass of kidneys was greater during winter than during summer, a result observed in other hibernating lizards but for which there is no clear explanation. Finally, the dry mass of testes showed a maximum value during autumn and a progressive reduction toward summer, indicating that reproduction occurs during autumn. When represented in a bivariate space, acquisition (digestive), distribution (heart, lungs and kidneys), storage (liver and fat bodies), and expenditure (testes) organs generate four clusters. In general terms, observed seasonal pattern of change in organ size is in agreement with those reported for other lizard species that inhabit highly fluctuating environments. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc.
Magnetic resonance microscopy of the barramundi (Lates calcarifer) brain
Authors: Ullmann Jeremy F.P. , Cowin, Gary , Collin Shaun P. 
Published: October 2010

AbstractMagnetic resonance imaging (MRI) is an established technique for morphological imaging of the central nervous system. Despite its prevalent use in a range of taxa, few studies exist on the brains of teleosts. In this study, we present a detailed analysis of a teleost brain using high‐resolution MRI. Images were acquired from a Bruker 16.4 T vertical magnet with a three‐dimensional flash T2*‐weighted image sequence. High contrast was obtained using Magnevist® and the following imaging parameters: a flip angle of 30°, a repetition time of 50 ms, an echo time of 14 ms, and an image matrix of 1024 × 400 × 400. The resulting isotropic resolution of 30 μm allowed us to thoroughly describe the architecture of the barramundi (Lates calcarifer) brain, including descriptions of nuclei, fiber tracts, and cellular layers. A good correspondence, both in contrast and morphology, was found between magnetic resonance images and Nissl‐stained brain sections, allowing for an analysis of the benefits and drawbacks of MRI and conventional histology. J. Morphol., 2010. © 2010 Wiley‐Liss, Inc..
Tandem mass spectrometry of silver‐adducted ferrocenyl catalyst complexes
Authors: Martha Cornelius T. , van Zeist Willem‐Jan , Bickelhaupt F. Matthias , Irth Hubertus , Niessen Wilfried M. A. 
Published: October 2010

AbstractFerrocene is a popular template in material science due to its exceptional characteristics that offer the ability to optimize the selectivity and activity of catalysts by the addition of carefully selected substituents. In combinatorial catalyst development, the high susceptibility to electrophilic substitution reactions offers the opportunity for the rapid introduction of molecular diversity. Mass spectrometry (MS)‐based continuous‐flow systems can be applied to rapidly evaluate catalyst performance as well as to (provisionally) identify the introduced catalyst complexes. Herein, we describe the fragmentation characteristics of the [ferrocenyl bidentate + Ag]+ catalyst complexes in dedicated (high‐resolution) MSn experiments. The investigation of the fragmentation patterns of a selected number of catalyst classes is accompanied with a density functional theory investigation of fragmentation intermediates in order to assess the viability of a selected fragmentation mechanism. Copyright © 2010 John Wiley & Sons, Ltd.
Energy‐dependent dissociation of benzylpyridinium ions in an ion‐trap mass spectrometer
Authors: Zins Emilie‐Laure , Pepe Claude , Schröder Detlef 
Published: October 2010

AbstractBenzylpyridinium ions, generated via electrospray ionization of dilute solutions of their salts in acetonitrile/water, are probed by collisional activation in an ion‐trap mass spectrometer. From the breakdown diagrams obtained, phenomenological appearance energies of the fragment ions are derived. Comparison of the appearance energies with calculated reaction endothermicities shows a reasonably good correlation for this particular class of compounds. In addition, the data indirectly indicate that at threshold the dissociation of almost all of the benzylpyridinium ions under study leads to the corresponding benzylium ions, rather than the tropylium isomers. Substituent effects on the fragmentation for a series of benzylpyridinium ions demonstrate that neither mass effects nor differences in density of states seriously affect the energetics derived from the ion‐trap experiments. Copyright © 2010 John Wiley & Sons, Ltd.
Phase I and II metabolites of speciogynine, a diastereomer of the mainKratomalkaloid mitragynine, identified in rat and human urine by liquid chromatography coupled to low‐ and high‐resolution linear ion trap mass spectrometry
Authors: Philipp Anika A. , Wissenbach Dirk K. , Weber Armin A. , Zapp Josef , Maurer Hans H. 
Published: October 2010

AbstractMitragyna speciosa(Kratomin Thai), a Thai medical plant, is misused as herbal drug of abuse. Besides the most abundant alkaloids mitragynine (MG) and paynantheine (PAY), several other alkaloids were isolated fromKratomleaves, among them the third abundant alkaloid is speciogynine (SG), a diastereomer of MG. The aim of this present study was to identify the phase I and II metabolites of SG in rat urine after the administration of a rather high dose of the pure alkaloid and then to confirm these findings using human urine samples afterKratomuse. The applied liquid chromatography coupled to low‐ and high‐resolution mass spectrometry (LC–HRMS‐MS) provided detailed information on the structure in the MSnmode particularly with high resolution. For the analysis of the human samples, the LC separation had to be improved markedly allowing the separation of SG and its metabolites from its diastereomer MG and its metabolites. In analogy to MG, besides SG, nine phase I and eight phase II metabolites could be identified in rat urine, but only three phase I and five phase II metabolites in human urine. These differences may be caused by the lower SG dose applied by the user ofKratompreparations. SG and its metabolites could be differentiated in the human samples from the diastereomeric MG and its metabolites comparing the different retention times determined after application of the single alkaloids to rats. In addition, some differences in MS2and/or MS3spectra of the corresponding diastereomers were observed. Copyright © 2010 John Wiley & Sons, Ltd.
Metabolic profiling of Escherichia coli by ion mobility‐mass spectrometry with MALDI ion source
Authors: Dwivedi Prabha , Puzon Geoffery , Tam Maggie , Langlais Denis , Jackson Shelley , Kaplan Kimberly , Siems William F. , Schultz Albert J. , Xun Luying , Woods Amina , Hill Herbert H. 
Published: October 2010

AbstractComprehensive metabolome analysis using mass spectrometry (MS) often results in a complex mass spectrum and difficult data analysis resulting from the signals of numerous small molecules in the metabolome. In addition, MS alone has difficulty measuring isobars and chiral, conformational and structural isomers. When a matrix‐assisted laser desorption ionization (MALDI) source is added, the difficulty and complexity are further increased. Signal interference between analyte signals and matrix ion signals produced by MALDI in the low mass region (<1500 Da) cause detection and/or identification of metabolites difficult by MS alone. However, ion mobility spectrometry (IMS) coupled with MS (IM–MS) provides a rapid analytical tool for measuring subtle structural differences in chemicals. IMS separates gas‐phase ions based on their size‐to‐charge ratio. This study, for the first time, reports the application of MALDI to the measurement of small molecules in a biological matrix by ion mobility‐time of flight mass spectrometry (IM‐TOFMS) and demonstrates the advantage of ion‐signal dispersion in the second dimension. Qualitative comparisons between metabolic profiling of the Escherichia coli metabolome by MALDI‐TOFMS, MALDI‐IM‐TOFMS and electrospray ionization (ESI)‐IM‐TOFMS are reported. Results demonstrate that mobility separation prior to mass analysis increases peak‐capacity through added dimensionality in measurement. Mobility separation also allows detection of metabolites in the matrix‐ion dominated low‐mass range (m/z < 1500 Da) by separating matrix signals from non‐matrix signals in mobility space. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis and characterization of a ‘fluorous’ (fluorinated alkyl) affinity reagent that labels primary amine groups in proteins/peptides
Authors: Qian Jiang , Cole Richard B. , Cai Yang 
Published: October 2010

AbstractStrong non‐covalent interactions such as biotin‐avidin affinity play critical roles in protein/peptide purification. A new type of ‘fluorous’ (fluorinated alkyl) affinity approach has gained popularity due especially to its low level of non‐specific binding to proteins/peptides. We have developed a novel water‐soluble fluorous labeling reagent that is reactive (via an active sulfo‐N‐hydroxylsuccinimidyl ester group) to primary amine groups in proteins/peptides. After fluorous affinity purification, the bulky fluorous tag moiety and the long oligoethylene glycol (OEG) spacer of this labeling reagent can be trimmed via the cleavage of an acid labile linker. Upon collision‐induced dissociation, the labeled peptide ion yields a characteristic fragment that can be retrieved from the residual portion of the fluorous affinity tag, and this fragment ion can serve as a marker to indicate that the relevant peptide has been successfully labeled. As a proof of principle, the newly synthesized fluorous labeling reagent was evaluated for peptide/protein labeling ability in phosphate‐buffered saline (PBS). Results show that both the aqueous environment protein/peptide labeling and the affinity enrichment/separation process were highly efficient. Copyright © 2010 John Wiley & Sons, Ltd.
Augmented adherence and internalization of group A Streptococcus pyogenes to influenza A virus infected MDCK cells
Authors: Hafez Mohamed M. , Abdel‐Wahab Kouka S. E. , El‐Fouhil Daad F. I. 
Published: October 2010

AbstractRespiratory tract infections are one of the leading causes of morbidity and mortality. There is considerable epidemiologic evidence that infection with respiratory viruses increases the incidence and severity of secondary bacterial complications. However, very limited number of studies were concerned with the mechanism behind such synergy. In this context, our study aimed to explore the interaction between Group A Streptococcus pyogenes (GAS) and Influenza A virus (IAV). Our results revealed that the GAS adherence and internalization into Madin‐Darby canine kidney (MDCK) cells markedly increased after IAV infection. When M6 protein defective mutant of GAS was used, the virus enhanced adherence and internalization was nearly abolished indicating the involvement of M protein binding sites on the MDCK cell surface. Interestingly, the modulation of some O‐linked glycolproteins as well as sialic acid, mucin and fibrinogen‐like residues on the surface of MDCK cells contributed to augmented bacterial adherence and/or internalization. In the same way, qRT‐PCR experiments showed an overexpression of the membrane associated mucin (MUC1) on the surface of the MDCK cells after IAV infection. Altogether, the present study revealed that IAV infection augments the adherence and internalization of GAS to MDCK cells via modulation of membrane associated O‐linked glycoproteins, fibrinogen, sialic acid residues and the mucin, MUC1 on the surface of MDCK cell. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Metamorphosis of Borrelia burgdorferi organisms – RNA, lipid and protein composition in context with the spirochetes' shape
Authors: Al‐Robaiy Samiya , Dihazi Hassan , Kacza Johannes , Seeger Johannes , Schiller Jürgen , Huster Daniel , Knauer Jens , Straubinger Reinhard K. 
Published: October 2010

AbstractBorrelia burgdorferi, the agent of Lyme borreliosis, has the ability to undergo morphological transformation from a motile spirochetal to non‐motile spherical shape when it encounters unfavorable conditions. However, little information is available on the mechanism that enables the bacterium to change its shape and whether major components of the cells – nucleic acids, proteins, lipids – are possibly modified during the process. Deducing from investigations utilizing electron microscopy, it seems that shape alteration begins with membrane budding followed by folding of the protoplasmatic cylinder inside the outer surface membrane. Scanning electron microscopy confirmed that a deficiency in producing functioning periplasmic flagella did not hinder sphere formation. Further, it was shown that the spirochetes' and spheres' lipid compositions were indistinguishable. Neither phosphatidylcholine nor phosphatidylglycerol were altered by the structural transformation. In addition, no changes in differential protein expression were detected during this process. However, minimal degradation of RNA and a reduced antigen‐antibody binding activity were observed with advanced age of the spheres. The results of our comparisons and the failure to generate mutants lacking the ability to convert to spheres suggest that the metamorphosis of B. burgdorferi results in a conditional reconstruction of the outer membrane. The spheres, which appear to be more resistant to unfavorable conditions and exhibit reduced immune reactivity when compared to spirochetes, might allow the B. burgdorferi to escape complete clearance and possibly ensure long‐term survival in the host. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Mode of action of plantaricin MG, a bacteriocin active against Salmonella typhimurium
Authors: Gong Han‐Sheng , Meng Xiang‐Chen , Wang Hui 
Published: October 2010

AbstractPlantaricin MG is a 2,180‐Da bacteriocin produced by Lactobacillus plantarum KLDS1.0391, which was isolated from Chinese traditional fermented cream. Plantaricin MG showed a broad inhibitory activity against not only Gram‐positive bacteria but also Gram‐negative bacteria including Listeria monocytogenes and Salmonella typhimurium. The mode of action of plantaricin MG on S. typhimurium was reported in this article. The addition of plantaricin MG to energized cells of S. typhimurium dissipated both, the transmembrane potential (Δψ) and the pH gradient (ΔpH). Energized membrane, obtained after the addition of glucose, was more susceptible to plantaricin MG action, leading to the release of intracellular K+ions, inorganic phosphate, ATP and UV‐absorbing materials. These data suggest that the presence of a proton motive force promotes the interaction of plantaricin MG with the cytoplasmic membrane of energized cells, leading to pores formation which allows the efflux of ions, thereby ensuring efficient killing of target bacteria. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Identification of bla OXA‐128 and bla OXA‐129, two novel OXA‐type extended‐spectrum‐β‐lactamases in Pseudomonas aeruginosa, in Hunan Province, China
Authors: Liu Wen'en , Liu Xiaoyi , Liao Jingzhong , Zhang Yunli , Liang Xianghui 
Published: October 2010

AbstractWe collected 97 non‐repetitive carbapenemases‐sensitive clinical isolates of Pseudomonas aeruginosa in Human Province, China, during the period of October 2006 to January 2007. From these isolates, we identified two novel oxacillin‐hydrolysing (OXA) type extended‐spectrum‐β‐lactamases (ESBLs): bla OXA‐128 and bla OXA‐129, which contain the mutations of I89V from bla OXA‐56 and K134N from bla OXA‐10, respectively. Clinical isolates containing either bla OXA‐128 or bla OXA‐129 show resistance to cephamycin‐class antibiotics but sensitive to carbapenem‐class antibiotics. The occurrence of novel OXA‐type lactamases suggests a regional prevalent pattern of ESBLs Pseudomonas aeruginosa in this area. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Success and failure in managing foreign acquisitions in South Korea and Japan: Lessons from Renault, General Motors, and DaimlerChrysler
Authors: Froese Fabian Jintae 
Published: October 2010

AbstractIn recent years, there has been a sharp increase in foreign merger‐and‐acquisition (M&A) activity in Japan and South Korea. Based on 23 interviews with Japanese, Korean, and foreign managers, this study investigates the reasons for success and failure in the management of the integration of foreign acquisitions in South Korea and Japan. Although the two implementations were independent of each other, Renault succeeded in both South Korea and Japan. On the other hand, General Motors struggled in Korea and DaimlerChrysler failed in Japan. Open communication, a participative leadership style, positive perspectives, and commitment were key factors for the success of Renault. While managers described plenty of similarities between integration processes in Korea and Japan, the reduced influence of conglomerates and the greater willingness of employees to accept changes may make Korea a more receptive environment. The article provides detailed background of the acquisitions and proposes recommendations as to how managers can successfully integrate Korean and Japanese target companies. © 2010 Wiley Periodicals, Inc.
Selecting candidates and managing expatriate assignments in China
Authors: Lund Daniel W. , Degen Ronald Jean 
Published: October 2010

AbstractTo ensure the success of expatriate assignment in China, it is critical that the most suitable candidates are chosen. This article provides a strategic model for selecting, training, and supporting personnel and their families for assignments in China and for helping them adjust to Chinese cultures. Home‐country reintegration strategies are also provided for developing experienced expatriates into global organizational leaders. Well‐planned selection, preparation, support, and reintegration programs help to increase expatriates' overall assignment effectiveness and avoid the high costs associated with expatriate failures. The proposed model is based on Fernandez and Underwood's (2006) critical success qualities of expatriate managers in China and Avril and Magnini's (2007) success qualities for expatriates and their families. A prescription for expatriate effectiveness is proposed based on Lund and Barker's (2007) study of expatriate managers' effectiveness in China, along with models for promoting effective pre‐departure preparation and new‐country adjustment support. © 2010 Wiley Periodicals, Inc.
Synthesis and Optical Properties of π‐Conjugated Polymers Composed of Benzo[1,2‐b:4,5‐b′]dithiophene and Thiophenes Bearing Electron‐Deficient Ethenyl Groups in the Side Chains
Authors: Lee Kwang‐Hoi , Lee Ho‐Jin , Morino Kazuhide , Sudo Atsushi , Endo Takeshi 
Published: October 2010

Abstractπ‐Conjugated polymers composed of dialkoxybenzo[1,2‐b:4,5‐b′]dithiophene and thiophenes bearing cyano‐alkoxycarbonylethenyl [CHC(CO2R)CN] and bis(alkoxycarbonyl)ethenyl groups [CHC(CO2R)2] were prepared. The optical properties of the obtained polymers were investigated by UV‐vis and photoluminescence spectroscopy to demonstrate that the absorption maxima of the polymers were tunable by varying the substituent of thiophene unit. The photoluminescence wavelengths and intensities of the polymer in solution were significantly dependent on the polymer side chain. The HOMO energy level of the polymer was lowered by up to −5.51 eV by introducing electron‐deficient cyano groups. Polymer solar cells based on the new polymers were fabricated to achieve a PCE of 1.90%. magnified image
Effects of Nematic Liquid Crystal Additives on the Performance of Polymer Solar Cells
Authors: Jeong Seonju , Kwon Younghwan , Choi Byeong‐Dae , Kwak Giseop , Han Yoon Soo 
Published: October 2010

AbstractNematic liquid crystals (NLCs), 4‐cyano‐4′‐pentylbiphenyl and 4‐cyano‐4′‐octylbiphenyl, were applied as additives to polymer solar cells with P3HT:PC61BM blend films. The incorporation of NLC additives led to a higher absorbance of the blend film, a higher crystallinity of P3HT, closer P3HT chains, larger PC61BM domains and enhanced hole/electron mobilities even without post‐thermal annealing. The non‐annealed PSC with 4 wt.‐% 8CB additives showed an increase in all parameters, resulting in a power conversion efficiency of 3.72% compared to 2.14% of the reference device without NLC additives. magnified image
Structure and Dynamics of Drawn Gel‐Spun Ultrahigh‐Molecular‐Weight Polyethylene Fibers by 1H, 13C and 129Xe NMR
Authors: Demco Dan E. , Melian Claudiu , Simmelink Jeff , Litvinov Victor M. , Möller Martin 
Published: October 2010

AbstractChanges in morphology and chain dynamics of a series of drawn gel‐spun UHMWPE fibers were investigated by 1D and 2D 1H, 13C and 129Xe NMR spectroscopy. The dependence of the rms oscillation angle for the internuclear proton spin pairs around the chain axis can be evaluated from 13C/1H WISE and correlated with the Young modulus of UHMWPE fibers. Based on the novel 13C QUCPMAS method it was shown that the relative amount of orthorhombic, monoclinic and intermediate fractions increase with the Young modulus as opposed to the highly mobile amorphous phase. The chain dynamics of this last fraction becomes less hindered. 129Xe NMR spectroscopy shows that the volume‐average diameter of voids increases with the Young modulus and the production of nanovoids is accelerated in drawn UHMWPE fibers. magnified image