bluuebunny/crossref_metadata_2025_split huggingface dataset:
CD8+ T Cell Responses to Lytic EBV Infection: Late Antigen Specificities as Subdominant Components of the Total Response
Authors: Abbott Rachel J. M. , Quinn Laura L. , Leese Alison M. , Scholes Harry M. , Pachnio Annette , Rickinson Alan B. 
Published: October 2013

AbstractEBV elicits primary CD8+ T cell responses that, by T cell cloning from infectious mononucleosis (IM) patients, appear skewed toward immediate early (IE) and some early (E) lytic cycle proteins, with late (L) proteins rarely targeted. However, L Ag-specific responses have been detected regularly in polyclonal T cell cultures from long-term virus carriers. To resolve this apparent difference between responses to primary and persistent infection, 13 long-term carriers were screened in ex vivo IFN-γ ELISPOT assays using peptides spanning the two IE, six representative E, and seven representative L proteins. This revealed memory CD8 responses to 44 new lytic cycle epitopes that straddle all three protein classes but, in terms of both frequency and size, maintain the IE &gt; E &gt; L hierarchy of immunodominance. Having identified the HLA restriction of 10 (including 7 L) new epitopes using memory CD8+ T cell clones, we looked in HLA-matched IM patients and found such reactivities but typically at low levels, explaining why they had gone undetected in the original IM clonal screens. Wherever tested, all CD8+ T cell clones against these novel lytic cycle epitopes recognized lytically infected cells naturally expressing their target Ag. Surprisingly, however, clones against the most frequently recognized L Ag, the BNRF1 tegument protein, also recognized latently infected, growth-transformed cells. We infer that BNRF1 is also a latent Ag that could be targeted in T cell therapy of EBV-driven B-lymphoproliferative disease.
Production of Monoclonal Antibodies
Authors: Yokoyama Wayne M. , Christensen Michelle , Santos Gary Dos , Miller Diane , Ho Jason , Wu Tao , Dziegelewski Michael , Neethling Francisca A. 
Published: October 2013

AbstractThis unit describes the production of monoclonal antibodies beginning with immunization, cell fusion, and selection. Support protocols are provided for screening primary hybridoma supernatants for antibodies of desired specificity, establishment of stable hybridoma lines, cloning of these B cell lines by limiting dilution to obtain monoclonal lines, and preparation of cloning/expansion medium. An alternate protocol describes cell fusion and one‐step selection and cloning of hybridomas utilizing a semi‐solid methylcellulose‐based medium (ClonaCell‐HY from StemCell Technologies). Curr. Protoc. Immunol. 102:2.5.1‐2.5.29. © 2013 by John Wiley & Sons, Inc.
Superresolution Imaging with Standard Fluorescent Probes
Authors: Millis Bryan A. , Burnette Dylan T. , Lippincott‐Schwartz Jennifer , Kachar Bechara 
Published: October 2013

AbstractFor more than 100 years, the ultimate resolution of a light microscope (∼200 nm) has been constrained by the fundamental physical phenomenon of diffraction, as described by Ernst Abbe in 1873. While this limitation is just as applicable to today's light microscopes, it is the combination of high‐end optics, clever methods of sample illumination, and computational techniques that has enabled researchers to access information at an order of magnitude greater resolution than once thought possible. This combination, broadly termed superresolution microscopy, has been increasingly practical for many labs to implement from both a hardware and software standpoint, but, as with many cutting‐edge techniques, it also comes with limitations. One of the current drawbacks to superresolution microscopy is the limited number of probes and conditions that have been suitable for imaging. Here, a technique termed bleaching/blinking‐assisted localization microscopy (BaLM) makes use of the inherent blinking and bleaching properties of almost all fluorophores as a means to generate superresolution images. Curr. Protoc. Cell Biol. 60:21.8.1‐21.8.17. © 2013 by John Wiley & Sons, Inc.
A comparison of the effects of initializing different thermosphere‐ionosphere model fields on storm time plasma density forecasts
Authors: Chartier Alex T. , Jackson David R. , Mitchell Cathryn N. 
Published: October 2013

AbstractData assimilation has been used successfully for real‐time ionospheric specification, but it has not yet proved advantageous for forecasting. The most challenging and important ionospheric events to forecast are storms. The work presented here examines the effectiveness of data assimilation in a storm situation, where the initial conditions are known and the model is considered to be correct but the external solar and geomagnetic drivers are poorly specified. The aim is to determine whether data assimilation could be used to improve storm time forecast accuracy. The results show that, in the case of the storm of Halloween 2003, changes made to the model's initial thermospheric conditions improve electron density forecasts by at least 10% for 18 h, while changes to ionospheric fields alone result in >10% forecast accuracy improvement for less than 4 h. Further examination shows that the neutral composition is especially important to the accuracy of ionospheric electron density forecasts. Updating the neutral composition gives almost all the benefits of updating the complete thermospheric state. A comparison with real, globally distributed observations of vertical total electron content confirms that updating the thermospheric composition can improve forecast accuracy.
Current structures associated with dipolarization fronts
Authors: Yao Zhonghua , Sun W. J. , Fu S. Y. , Pu Z. Y. , Liu Jiang , Angelopoulos V. , Zhang X.‐J. , Chu X. N. , Shi Q. Q. , Guo R. L. , Zong Q.‐G. 
Published: October 2013

AbstractRecently, observational results on currents around the dipolarization fronts (DFs) of earthward flow bursts have attracted much research attention. These currents are found to have close association with substorm intensifications. This paper devotes to further study of the current system ahead and within the DFs with high‐resolution magnetic field measurements from Cluster constellation in 2003. The separation of four spacecraft is much smaller than the scales of spatial structures ahead and within the DF layer so that the currents can be reliably obtained. Based on features of the magnetic field variations prior to the fronts, we categorized the DFs into two types: DFs with magnetic dips immediate ahead of the fronts (type I) and DFs without magnetic dips (type II). For type I DFs, it is found that dawnward currents along the DFs exist in the dip region; duskward currents exist within the fronts. Furthermore, the dawnward currents in the dip region are found to be mainly parallel to the local magnetic field with a spatial scale of ~1000 km, whereas the duskward currents within the fronts have both significant parallel and perpendicular components. On the other hand, for type II DFs, only significant duskward and mainly perpendicular currents show up within the fronts; no dawnward currents exist ahead of DFs. The dawnward and mainly parallel current in the type I DFs is important in the current coupling process between magnetosphere and ionosphere and may lead to local current disruptions for substorm initiations.
Genetic Manipulation of Streptococcus pyogenes (The Group A Streptococcus, GAS)
Authors: Le Breton Yoann , McIver Kevin S. 
Published: October 2013

AbstractStreptococcus pyogenes (the Group A Streptococcus, GAS) is a Gram‐positive bacterium responsible for a wide spectrum of diseases ranging from mild superficial infections (pharyngitis, impetigo) to severe, often life‐threatening invasive diseases (necrotizing fasciitis, streptococcal toxic shock syndrome) in humans. This unit describes molecular techniques for the genetic manipulation of S. pyogenes with detailed protocols for transformation, gene disruption, allelic exchange, transposon mutagenesis, and genetic complementation. Curr. Protoc. Microbiol. 30:9D.3.1‐9D.3.29. © 2013 by John Wiley & Sons, Inc.
Addition of amino acid moieties to lapatinib increases the anti‐cancer effect via amino acid transporters
Authors: Maeng Han‐Joo , Kim Eun‐Seo , Chough Chieyeon , Joung Misuk , Lim Jee Woong , Shim Chang‐Koo , Shim Won‐Sik 
Published: October 2013

ABSTRACTAnti‐cancer agents delivered to cancer cells often show multi‐drug resistance (MDR) due to expulsion of the agents. One way to address this problem is to increase the accumulation of anti‐cancer agents in cells via amino acid transporters. Thus, val‐lapatinib and tyr‐lapatinib were newly synthesized by adding valine and tyrosine moieties, respectively, to the parent anti‐cancer agent lapatinib without stability issues in rat plasma. Val‐lapatinib and tyr‐lapatinib showed enhanced anti‐cancer effects versus the parent lapatinib in various cancer cell lines, including human breast cancer cells (MDA‐MB‐231, MCF7) and lung cancer cells (A549), but not in non‐cancerous MDCK‐II cells. A glutamine uptake study revealed that both val‐lapatinib and tyr‐lapatinib, but not the parent lapatinib, inhibited glutamine transport in MDA‐MB‐231 and MCF7 cells, suggesting the involvement of amino acid transporters. In conclusion, val‐lapatinib and tyr‐lapatinib have enhanced anti‐cancer effects, likely due to an increased uptake of the agents into cancer cells via amino acid transporters. The present data suggest that amino acid transporters may be an effective drug delivery target to increase the uptake of anti‐cancer agents, leading to one method of overcoming MDR in cancer cells. Copyright © 2013 John Wiley & Sons, Ltd.
Iterative Antimicrobial Candidate Selection from Informed D‐/L‐Peptide Dimer Libraries
Authors: Lichtenecker Roman J. , Ellinger Bernhard , Han Hong‐Mei , Jadhav Kirtikumar B. , Baumann Sascha , Makarewicz Oliwia , Grabenbauer Markus , Arndt Hans‐Dieter 
Published: October 2013

AbstractGrowing resistance to antibiotics, as well as newly emerging pathogens, stimulate the investigation of antimicrobial peptides (AMPs) as therapeutic agents. Here, we report a new library design concept based on a stochastic distribution of natural AMP amino acid sequences onto half‐length synthetic peptides. For these compounds, a non‐natural motif of alternating D‐ and L‐backbone stereochemistry of the peptide chain predisposed for β‐helix formation was explored. Synthetic D‐/L‐peptides with permuted half‐length sequences were delineated from a full‐length starter sequence and covalently recombined to create two‐dimensional compound arrays for antibacterial screening. Using the natural AMP magainin as a seed sequence, we identified and iteratively optimized hit compounds showing high antimicrobial activity against Gram‐positive and Gram‐negative bacteria with low hemolytic activity. Cryo‐electron microscopy characterized the membrane‐associated mechanism of action of the new D‐/L‐peptide antibiotics.
CO2 Complexation and Activation by a Trost‐Bis(ProPhenol)Cobalt Complex
Authors: Netto Caterina G. C. M. , Toma Henrique E. 
Published: October 2013

AbstractA binuclear cobalt complex, [Co2BPP], derived from the (R,R)‐Trost‐bis‐ProPhenol (BPP) ligand, has been investigated as a catalyst for CO2 uptake and its electrochemical reduction. The complex exhibits labile acetate ligands that can be readily exchanged with CO2, leading to pronounced changes in its vibrational spectra, with νC=O peaks observed at 1700 and 1596 cm–1. The electrochemical reduction of the CoIII centers at –0.5 V was significantly enhanced in the presence of CO2, evidencing a chemical reaction coupled to an electrode process. Instead of yielding CO or HCOOH as observed in most artificial systems, formaldehyde was identified as the major product below –1.0 V, showing that CO2 can undergo four‐electron reduction by the [Co2BPP] electrocatalyst.
The effect of ethylene oxide sterilization on the surface chemistry and in vitro cytotoxicity of several kinds of chitosan
Authors: França Rodrigo , Mbeh Doris A. , Samani Taraneh Djavanbakht , Le Tien Canh , Mateescu Mircea A. , Yahia L'Hocine , Sacher Edward 
Published: October 2013

AbstractThe surfaces of three chitosan samples, differing only in their degrees of deacetylation and of carboxyethyl chitosan were chemically characterized by X‐ray photoelectron spectroscopy, time‐of‐flight secondary ion mass spectroscopy, X‐ray diffraction, and Fourier transform infrared, both before and after sterilization with ethylene oxide. Unexpected elemental ratios suggest that surface chemical modification occurred during the processing of the original chitin, with further surface modification on subsequent sterilization, despite previous reports to the contrary. Cell viability was evaluated by direct contact methyl thiazole tetrazolium and lactate dehydrogenase assays between the chitosan particles and A549 human epithelial cells, which demonstrated that the modifications incurred on sterilization are reflected in biocompatibility changes. All the samples were found to be biocompatible and nontoxic before sterilization and remained so subsequently. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 101B: 1444–1455, 2013.
Picomole‐level Formaldehyde Determination in Gaseous and Beer Samples Using Flow Injection Chemiluminescence Analysis
Authors: Tan Xijuan , Song Zhenghua 
Published: October 2013

AbstractBased on the linear enhancement of formaldehyde (FA) within 7.0 ∼ 1000 pmol l−1 on luminol—bovine serum albumin (BSA) chemiluminescence (CL) system, FA determination in air and beer samples using CL with flow injection (FI) was proposed. The detection limit was 2.5 pmol l−1 (3σ) and the relative standard deviations were less than 4.5% (n = 7). At a flow rate of 2.0 mL min−1, a whole analysis from sampling to washing only needed 32 s, offering a sample throughput of 112 h−1. This proposed method was successfully utilized to determine FA vapor pressure in liquid (121.8 ± 3.8 Pa), FA content in real air sample (8.93 ± 0.03 mg m−3), and FA levels in beer (199.5 ± 5.6 ∼ 225.2 ± 3.5 mg l−1), giving determination recoveries from 90.7% to 109.3%. The mechanism of BSA—FA interaction was also investigated, showing FA binding to BSA was a spontaneous process mainly through hydrogen bonding and van der Waals force by FI‐CL, with binding constant K of 1.89 × 106 l mol−1 and the number of binding sites n of 0.86. Molecular docking analysis further revealed FA could enter into the pocket at subdomain IIA of BSA, with K of 1.71 × 105 l mol−1 and ΔG of ‐29.68 kJ mol−1.
Is the thrombus truly free‐floating? A case report
Authors: Demir Kenan , Avci Ahmet , Altunkeser Bulent Behlul , Ugras Nevzat Serdar 
Published: October 2013

ABSTRACTA free‐floating thrombus in the left atrium is very rare in mitral stenosis. Such a thrombus can lead to sudden circulatory arrest and syncope or can cause severe cerebral or peripheral thromboembolic events. Clinical diagnosis is difficult, but left atrial thrombus should be suspected if patients with mitral stenosis and atrial fibrillation have intermittent or changing murmurs, emboli, or syncope. We describe the case of a patient with mild mitral stenosis under warfarin therapy, and a left atrial pedunculated thrombus discovered during the investigation for syncope attacks. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound 42:252–255, 2014
Longitudinal changes in MRI markers in a reversible unilateral ureteral obstruction mouse model: Preliminary experience
Authors: Haque Muhammad E. , Franklin Tammy , Bokhary Ujala , Mathew Liby , Hack Bradley K. , Chang Anthony , Puri Tipu S. , Prasad Pottumarthi V. 
Published: October 2013

PurposeTo evaluate longitudinal changes in renal oxygenation and diffusion measurements in a model of reversible unilateral ureteral obstruction (rUUO) which has been shown to induce chronic renal functional deficits in a strain dependent way. C57BL/6 mice show higher degree of functional deficit compared with BALB/c mice. Because hypoxia and development of fibrosis are associated with chronic kidney diseases and are responsible for progression, we hypothesized that MRI measurements would be able to monitor the longitudinal changes in this model and will show strain dependent differences in response. Here blood oxygenation level dependent (BOLD) and diffusion MRI measurements were performed at three time points over a 30 day period in mice with rUUO.Materials and MethodsThe studies were performed on a 4.7T scanner with the mice anesthetized with isoflurane before UUO, 2 and 28 days postrelease of 6 days of obstruction.ResultsWe found at the early time point (∼2 days after releasing the obstruction), the relative oxygenation in C57Bl/6 mice were lower compared with BALB/c. Diffusion measurements were lower at this time point and reached statistical significance in BALB/cConclusionThese methods may prove valuable in better understanding the natural progression of kidney diseases and in evaluating novel interventions to limit progression. J. Magn. Reson. Imaging 2014;39:835–841. © 2013 Wiley Periodicals, Inc.
Temperature‐Induced Formation of Polymeric Nanoparticles: In Situ SAXS and QENS Experiments
Authors: Sedlak Marian , Falus Peter , Steinhart Milos , Gummel Jeremie , Stepanek Petr , Filippov Sergey K. 
Published: October 2013

Early stages of polymeric nanoparticle formation are monitored by in situ synchrotron small‐angle X‐ray scattering (SAXS) experiments. A new strategy enables the preparation of stable polymeric nanoparticles from homopolymers (not copolymers) of one type only and without any assembly‐triggering additives. Poly(ethylacrylic acid) (PEA) in an aqueous solution is tuned to the pH, where it exhibits thermosensitivity and the formation of nanoparticles is temperature‐induced. The kinetics of this formation are clearly monitored by SAXS. Experiments indicate the slightly elongated, not exactly spherical shape of the resulting nanoparticles, which is also confirmed by cryo‐transmission electron microscopy (cryo‐TEM). Quasielastic neutron scattering (QENS) shows that the PEA nanoparticles are relatively loose with a lot of solvent inside, in agreement with results from previous light scattering work.
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Feasibility of semiautomated MR volumetry using gadoxetic acid–enhanced MRI at hepatobiliary phase for living liver donors
Authors: Lee Jeongjin , Kim Kyoung Won , Kim So Yeon , Kim Bohyoung , Lee So Jung , Kim Hyoung Jung , Lee Jong Seok , Lee Moon Gyu , Song Gi‐Won , Hwang Shin , Lee Sung‐Gyu 
Published: October 2013

PurposeTo assess the feasibility of semiautomated MR volumetry using gadoxetic acid–enhanced MRI at the hepatobiliary phase compared with manual CT volumetry.MethodsForty potential live liver donor candidates who underwent MR and CT on the same day, were included in our study. Semiautomated MR volumetry was performed using gadoxetic acid–enhanced MRI at the hepatobiliary phase. We performed the quadratic MR image division for correction of the bias field inhomogeneity. With manual CT volumetry as the reference standard, we calculated the average volume measurement error of the semiautomated MR volumetry. We also calculated the mean of the number and time of the manual editing, edited volume, and total processing time.ResultsThe average volume measurement errors of the semiautomated MR volumetry were 2.35% ± 1.22%. The average values of the numbers of editing, operation times of manual editing, edited volumes, and total processing time for the semiautomated MR volumetry were 1.9 ± 0.6, 8.1 ± 2.7 s, 12.4 ± 8.8 mL, and 11.7 ± 2.9 s, respectively.ConclusionSemiautomated liver MR volumetry using hepatobiliary phase gadoxetic acid–enhanced MRI with the quadratic MR image division is a reliable, easy, and fast tool to measure liver volume in potential living liver donors. Magn Reson Med 72:640–645, 2014. © 2013 Wiley Periodicals, Inc.
Temperature effects on the hydrodynamic radius of the intrinsically disordered N‐terminal region of the p53 protein
Authors: Langridge Timothy D. , Tarver Micheal J. , Whitten Steven T. 
Published: October 2013

ABSTRACTIntrinsically disordered proteins (IDPs) are often characterized in terms of the hydrodynamic radius, Rh. The Rh of IDPs are known to depend on fractional proline content and net charge, where increased numbers of proline residues and increased net charge cause larger Rh. Though sequence and charge effects on the Rh of IDPs have been studied, the temperature sensitivity has been noted only briefly. Reported here are Rh measurements in the temperature range of 5–75°C for the intrinsically disordered N‐terminal region of the p53 protein, p53(1–93). Of note, the Rh of this protein fragment was highly sensitive to temperature, decreasing from 35 Å at 5°C to 26 Å at 75°C. Computer generated simulations of conformationally dynamic and disordered polypeptide chains were performed to provide a hypothesis for the heat‐induced compaction of p53(1–93) structure, which was opposite to the heat‐induced increase in Rh observed for a model folded protein. The simulations demonstrated that heat caused Rh to trend toward statistical coil values for both proteins, indicating that the effects of heat on p53(1–93) structure could be interpreted as thermal denaturation. The simulation data also predicted that proline content contributed minimally to the native Rh of p53(1–93), which was confirmed by measuring Rh for a substitution variant that had all 22 proline residues changed for glycine. Proteins 2014; 82:668–678. © 2013 Wiley Periodicals, Inc.
Influence of Individual Phospholipids on the Physical Properties of Oil‐Based Suspensions
Authors: Arnold G. , Schade E. , Schneider Y. , Friedrichs J. , Babick F. , Werner C. , Rohm H. 
Published: October 2013

AbstractThe impact of soybean lecithin and three individual phospholipids at different concentration (CPL) on rheology and sedimentation behavior of sugar/soybean oil suspensions (ϕ = 0.31) was studied and compared with attraction and retraction forces between sugar surfaces in soybean oil as measured by atomic force microscopy (AFM). In general, a surfactant‐induced reduction of yield stress, apparent viscosity and sediment volume of the suspensions coincides with a decrease of adhesive interactions between sugar particles in soybean oil. Although the general influence of individual phospholipids and soybean lecithin is comparable, it is concluded from investigations at low CPL that individual phospholipids exhibit a less pronounced impact on the analyzed parameters. Furthermore, at low CPL, binary mixtures of the phospholipids are more efficient than individual phospholipids as regards the reduction of yield stress and sediment volume. While the same tendency was detectable for AFM results, these differences were not statistically verified. Slight differences were also evident when comparing individual phospholipids and their influence on rheology and sedimentation which are, however, not in line with the results of AFM. A general understanding of these interrelations between surfactant composition and possible synergistic or antagonistic effects in mixtures of individual phospholipids contributes to optimizing lecithin composition with respect to functionality.