bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of glycosylation on the antibody recognition of a MUC2 mucin epitope
Authors: Uray Katalin , Mizuno Mamoru , Inazu Toshiyuki , Goto Kohtaro , Hudecz Ferenc 
Published: August 2014

ABSTRACTMUC2 glycoprotein, produced by the epithelium of the colon and built up mainly of repeat units of 1PTTTPITTTTTVTPTPTPTGTQT23, can be overexpressed or underglycosylated in gastrointestinal diseases, e.g. in case of colon carcinoma. We have been studying the epitope structure of the MUC2 by focusing on the repeat unit with the mucin peptide specific MAb 996 monoclonal antibody. This antibody recognizes the 18PTGTQ22 sequence as minimal, and 16PTPTGTQ22 as optimal epitope within the underglycosylated glycoprotein. In this article, we aim to clarify the effect of glycosylation of the epitope on MAb 996 antibody binding including its correlation with the secondary structure of the modified peptides: glycosylation in the epitope core and in the flank. For this we have prepared the 16PTPTGTQ22 peptide glycosylated with N‐acetylgalactoseamine (Tn antigen) in position 17, 19, 21, or on all three threonines. The MAb 996 antibody binding properties of the peptides were characterized in competitive ELISA experiments, and their solution secondary structure was studied by circular dichroism spectroscopy in water and in the ordered structure promoting trifluoroethanol. Our results show that glycosylation in position 19 (peptide 16PTPT(GalNAcα)GTQ22) resulted in enhanced antibody recognition and significantly altered secondary structure, while glycosylation in position 21 completely demolished the binding. These findings could be useful in determining the nature of antigen–antibody interaction, and perhaps designing synthetic peptide vaccines for tumor therapy. © 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 390–395, 2014.
Bifunctional DNA Architectonics: Three‐Way Junctions with Sticky Perylene Bisimide Caps and a Central Metal Lock
Authors: Stubinitzky Claudia , Bijeljanin Andrea , Antusch Linda , Ebeling Daniel , Hölscher Hendrik , Wagenknecht Hans‐Achim 
Published: August 2014

AbstractA new type of a bifunctional DNA architecture based on a three way junction is developed that combines the structural motif of sticky perylene bisimide caps with a tris‐bipyridyl metal ion lock in the center part. A clear stabilizing effect was observed in the presence of Fe3+, Ni2+ and Zn2+ by the formation of corresponding bipyridyl complexes in the branching part of the DNA three way junctions. The dimerization of the 5′‐terminally attached perylene diimides (PDI) chromophores by hydrophobic interactions can be followed by significant changes in the UV/Vis absorption and steady‐state fluorescence. The PDI‐mediated DNA assembly occurs at temperatures below the melting temperature and is not influenced by the metal‐ion bipyridyl locks in the central part. The corresponding AFM images revealed the formation of higher‐ordered structures as the result of DNA assemblies mediated by the PDI interactions.
Photoluminescent Carbon Dots from 1,4‐Addition Polymers
Authors: Jiang Zhiqiang , Nolan Andrew , Walton Jeffrey G. A. , Lilienkampf Annamaria , Zhang Rong , Bradley Mark 
Published: August 2014

AbstractPhotoluminescent carbon dots were synthesised directly by thermopyrolysis of 1,4‐addition polymers, allowing precise control of their properties. The effect of polymer composition on the properties of the carbon dots was investigated by TEM, IR, XPS, elemental analysis and fluorescence analysis, with carbon dots synthesised from nitrogen‐containing polymers showing the highest fluorescence. The carbon dots with high nitrogen content were observed to have strong fluorescence in the visible region, and culture with cells showed that the carbon dots were non‐cytotoxic and readily taken up by three different cell lines.
Cyclobutene Formation in PtCl2‐Catalyzed Cycloisomerizations of Heteroatom‐Tethered 1,6‐Enynes
Authors: Ni Zhenjie , Giordano Laurent , Tenaglia Alphonse 
Published: August 2014

AbstractAza(oxa)bicyclo[3.2.0]heptenes are accessed through the PtCl2‐catalyzed cycloisomerizations of heteroatom‐tethered 1,6‐enynes featuring a terminal alkyne and amide as the solvent. It is shown that the weak coordinating properties of the solvent and alkyl substituent(s) at the propargylic carbon atom favor the formation of cyclobutenes instead of other possible cycloisomerization products such as 1,3‐diene derivatives or cyclopropane‐fused heterocycles.
Efficient Perovskite Solar Cells with 13.63 % Efficiency Based on Planar Triphenylamine Hole Conductors
Authors: Choi Hyeju , Paek Sanghyun , Lim Namwoo , Lee Yong Hui , Nazeeruddin Mohammad Khaja , Ko Jaejung 
Published: August 2014

AbstractA new type of hole transporting material (HTMs) with an incorporated planar amine or triphenylamine as a core unit have been prepared. The two amine derivatives were demonstrated to be efficient hole transporting materials in fabricating solid‐state organic–inorganic hybrid solar cells. Perovskite‐based solar cells with a planar amine derivative gave a short circuit photocurrent density (Jsc) of 20.98 m Acm−2, an open circuit voltage (Voc) of 0.972 V, and a fill factor of 0.67, corresponding to an overall conversion efficiency of 13.63 %. The photovoltaic performance is comparable to that of the standard spiro‐OMeTAD. Moreover, the device showed good stability under light soaking for 500 h. These HTMs hold promise to replace the expensive spiro‐OMeTAD because of their high efficiency, excellent stability, synthesis from simple and inexpensive materials.
Effect of Constant‐Rate Reduction on the Performance of a Ternary Cu/ZnO/Al2O3 Catalyst in Methanol Synthesis
Authors: Ruland Holger , Busser Wilma , Otto Horst , Muhler Martin 
Published: August 2014

AbstractA multi‐functional flow set‐up was developed for the rate‐ and temperature‐controlled reduction of copper catalysts, their application in high‐pressure methanol synthesis and the determination of the copper surface area by N2O frontal chromatography. The influence of constant‐rate reduction on the catalytic properties of a ternary Cu/ZnO/Al2O3 catalyst was investigated. The temperature during the constant‐rate reduction was found to decrease, indicating autocatalytic kinetics, but no significant catalytic effect of the milder reduction conditions was observed compared with a slow linear heating ramp.
Halogenierte Naturstoffe
Authors: Hille‐Rehfeld Annette 
Published: August 2014

AbstractBiogene halogenierte Kohlenwasserstoffe mit ihrer strukturellen und funktionellen Vielfalt sind ein expandierendes Forschungsfeld der chemischen Ökologie. Sie bieten Leitstrukturen für die Entwicklung vielfältiger Wirkstoffe, vom Antibiotikum über Cytostatika bis hin zu Antifouling‐Agentien.
Synthetisches Blau als Wegbereiterin des Impressionismus
Authors: Bützer Peter 
Published: August 2014

AbstractDie vielen stabilen leicht verfügbaren, günstigen synthetischen blauen Pigmente, die seit dem Anfang des 18. und vor allem am Anfang des 19. Jahrhunderts hergestellt wurden, haben die notwendigen Voraussetzungen und Chancengleichheit in der Malerei geschaffen und den Impressionismus mit dem ganzen Farbspektrum und all seinen Nuancen erst ermöglicht.
Die Chemie bei Breaking Bad
Authors: Salthammer Tunga , Harnisch Falk 
Published: August 2014

AbstractDer in Heft 4/2013 der ChiuZ publizierte Artikel über die Chemie in der Kultserie “Breaking Bad” hat mit seiner außergewöhnlich großen Resonanz die Erwartungen von Autoren und Redaktion weit übertroffen. Ein Resumee.
Atomistic‐Level Portrayal of Drug–DNA Interplay: A History of Courtships and Meetings Revealed by Molecular Simulations
Authors: Vargiu Attilio V. , Magistrato Alessandra 
Published: August 2014

AbstractSimulation techniques play an ever increasing role in drug design by providing an atomistic view of the pathways of drugs to their target sites, thus revealing the determinants behind molecular recognition and binding, pinpointing local and allosteric conformational changes of both drugs and receptors, and unveiling key chemical mechanisms in enzymatic‐like processes. In particular, molecular dynamics simulations, relying on a force field, quantum mechanical, or hybrid description of the system, have been largely employed to unveil mechanistic, kinetic, and thermodynamic aspects of the binding of anticancer drugs to DNA, ultimately contributing to a better understanding of their mechanism of action. Herein we review recent literature, focusing on selected examples from our work, to show how modern computer simulations can be applied to study the mechanism of action of antitumor drugs such as platinum compounds, organic antibiotics, and metal‐based octahedral complexes, which are archetypal examples of the most common classes of DNA binding molecules. We discuss the strengths and limitations of in silico studies in this field, as well as current and future challenges.
The Design of RNA Binders: Targeting the HIV Replication Cycle as a Case Study
Authors: Blond Aurélie , Ennifar Eric , Tisné Carine , Micouin Laurent 
Published: August 2014

AbstractThe human immunodeficiency virus 1 (HIV‐1) replication cycle is finely tuned with many important steps involving RNA–RNA or protein–RNA interactions, all of them being potential targets for the development of new antiviral compounds. This cycle can also be considered as a good benchmark for the evaluation of early‐stage strategies aiming at designing drugs that bind to RNA, with the possibility to correlate in vitro activities with antiviral properties. In this review, we highlight different approaches developed to interfere with four important steps of the HIV‐1 replication cycle: the early stage of reverse transcription, the transactivation of viral transcription, the nuclear export of partially spliced transcripts and the dimerization step.
Cost of services provided by theNationalBreast andCervicalCancer EarlyDetectionProgram
Authors: Ekwueme Donatus U. , Subramanian Sujha , Trogdon Justin G. , Miller Jacqueline W. , Royalty Janet E. , Li Chunyu , Guy Gery P. , Crouse Wesley , Thompson Hope , Gardner James G. 
Published: August 2014

BACKGROUNDThe National Breast and Cervical Cancer Early Detection Program (NBCCEDP) is the largest cancer screening program for low‐income women in the United States. This study updates previous estimates of the costs of delivering preventive cancer screening services in the NBCCEDP.METHODS:We developed a standardized web‐based cost‐assessment tool to collect annual activity‐based cost data on screening for breast and cervical cancer in the NBCCEDP. Data were collected from 63 of the 66 programs that received funding from the Centers for Disease Control and Prevention during the 2006/2007 fiscal year. We used these data to calculate costs of delivering preventive public health services in the program.RESULTS:We estimated the total cost of all NBCCEDP services to be $296 (standard deviation [SD], $123) per woman served (including the estimated value of in‐kind donations, which constituted approximately 15% of this total estimated cost). The estimated cost of screening and diagnostic services was $145 (SD, $38) per women served, which represented 57.7% of the total cost excluding the value of in‐kind donations. Including the value of in‐kind donations, the weighted mean cost of screening a woman for breast cancer was $110 with an office visit and $88 without, the weighted mean cost of a diagnostic procedure was $401, and the weighted mean cost per breast cancer detected was $35,480. For cervical cancer, the corresponding cost estimates were $61, $21, $415, and $18,995, respectively.CONCLUSIONS:These NBCCEDP cost estimates may help policy makers in planning and implementing future costs for various potential changes to the program.Cancer2014;120(16 suppl):2604‐11.©2014 American Cancer Society.
Maintaining channel abandonment processes increases riparian plant diversity within fluvial corridors
Authors: Dufour Simon , Hayden Maya , Stella John , Battles John , Piegay Herve 
Published: August 2014

AbstractWithin dynamic alluvial riverine corridors, abandoned channels form and experience hydrogeomorphic processes that are distinct from similar elevation surfaces along active channels. Compared with the relatively well‐studied role of fluvial disturbance on floodplain plant communities along active channels, the drivers of plant diversity and community dynamics along terrestrializing abandoned channels have received much less attention. In this study, we addressed several related questions within the context of the Sacramento River (California, USA): (1) Do abandoned channels host different plant species compared with the surrounding floodplain? (2) How do plant communities vary among abandoned channels in relation to time since cutoff and disturbance regime? (3) Do understory plant species within an abandoned channel display distinct zonation along a disturbance gradient from the wetted edge laterally to upland areas? Our results show that although species richness is similar to floodplain sites, abandoned channels support a different species pool, notably due to presence of more wetland‐associated species, and this contributes to increase biodiversity within the fluvial corridor. We found substantial shifts in species composition that occurred since channel abandonment, likely related to decreases in the strength of hydromorphic disturbance through time. Lastly, we found that lateral environmental gradients within abandoned channel sites were significant, although much weaker drivers of understory vegetation patterns than typically found along active channel banks. These results argue for a management approach that preserves and promotes natural processes of channel migration and sediment dynamics. Copyright © 2014 John Wiley & Sons, Ltd.
Systematic Study of the Electronic States in Electron‐Doped Polyacenes
Authors: Phan Quynh T. N. , Heguri Satoshi , Tanabe Yoichi , Shimotani Hidekazu , Tanigaki Katsumi 
Published: August 2014

AbstractHigh‐quality polycrystalline polyacenes (PLAs) of anthracene (AN), tetracene (TN), and pentacene (PN) doped with potassium in the 1:1 and 1:2 stoichiometries are prepared and their physical properties are systematically studied by magnetic measurements. The magnetic susceptibilities as a function of temperature for Kx(PLAs) are interpreted in the framework of a band‐filling model. Clear evidence for the occurrence of charge transfer from K to the organic semiconductors is provided. K1(AN) prepared by a solid‐state diffusion process exhibits a pronounced magnetic hump at 140 K, which is associated with antiferromagnetic interactions ascribed to the on‐site Coulomb repulsion in a Mott insulating state, whereas both K1(TN) and K1(PN) show a conventional Curie–Weiss behavior at low temperatures. We successfully demonstrate the tuning of the electronic states of PLA‐type semiconductors in bulk. Comments are given about the possibility of metallic states in potassium‐doped PLAs, which have recently been reported for other polycyclic aromatic hydrocarbons.
Magnetic resonance spectroscopy measurements of intragastric fat fraction of oil emulsions in humans
Authors: Hussein Mahamoud O. , Hoad Caroline L. , Stephenson Mary C. , Cox Eleanor F. , Placidi Elisa , Pritchard Susan E. , Costigan Carolyn , Ribeiro Henelyta. , Ciampi Elisabetta , Rayment Pip , Nandi Asish , Hedges Nick , Sanderson Paul , Peters Harry P.F. , Kruse Irmela , Marciani Luca , Spiller Robin C. , Gowland Penny A. 
Published: August 2014

There is considerable interest in manipulating the behavior of dietary emulsions in the human stomach as a means of altering satiating properties of fatty foods. However assessing this using intubation markedly disturbs normal gastric motility so a non‐invasive imaging approach has a strong rationale. Two 20% sunflower oil‐in‐water fat emulsions test meals with different droplet sizes (termed Fine and Coarse) and intragastric behaviors were used to demonstrate, for the first time, the feasibility of carrying out magnetic resonance spectroscopy (MRS) measurements of fat emulsions fat fraction, in vivo, in the gastric lumen of six healthy volunteers. Magnetic resonance imaging (MRI) confirmed that as expected the fine emulsion remained mostly homogeneously distributed inside the stomach over the course of 3 h but the Coarse quickly creamed showing an upper layer much richer in fat. The MRS measurements showed that the Coarse emulsion had an upper layer of high lipid/water ratio compared to the lower layer. The fine emulsion fat fraction values remained stable throughout the study with no difference between upper and lower layers. It is therefore possible to quantify in vivo, in the gastric lumen, the intragastric fat fraction of oil‐in‐water fat emulsions using non invasive MRS techniques.Practical applications: This study shows that it is possible to quantify in vivo, in the gastric lumen, the intragastric fat fraction of oil‐in‐water fat emulsions using non invasive magnetic resonance spectroscopy techniques. These measurements can help improve understanding of intragastric distribution of fat, its relation to satiety, can improve the relevance of in vitro/in vivo models of fat digestion, and will ultimately aid the design of foods with desired health promoting characteristics and check their performance in vivo.Two 20% sunflower oil‐in‐water fat emulsions test meals with different droplet sizes and intragastric behaviours are used to demonstrate, for the first time, the feasibility of carrying out magnetic resonance spectroscopy (MRS) measurements of fat emulsions fat fraction, in vivo, in the gastric lumen of six healthy volunteers.
Ring‐Closing Metathesis of Vinyl Fluorides towards α‐Fluorinated α,β‐Unsaturated Lactams and Lactones
Authors: Marhold Michael , Stillig Christian , Fröhlich Roland , Haufe Günter 
Published: August 2014

AbstractRing‐closing olefin metathesis reactions (RCM) using Grubbs II or Hoveyda's catalysts have been applied to a series of N‐alkenyl‐N‐benzyl‐α‐fluoroacrylamides. α‐Fluoro‐α,β‐unsaturated γ‐ or δ‐lactams incorporating a fluorinated double bond were obtained in moderate to good yields, depending on the nature of substituents on the benzyl ring. The corresponding seven‐ and eight‐membered lactams were not formed under similar conditions. When the N‐benzyl group was replaced by an N‐tosyl group, the corresponding ϵ‐lactam was also formed in 38 % yield. When N‐(2‐fluoroallyl) derivatives were used instead of fluoroacryloyl derivatives, six‐, seven‐, and eight‐membered N‐heterocycles were obtained in low yields. This method was also used to synthesize fluorinated α,β‐unsaturated analogues of pyrrolizidine and indolizidine alkaloids from prolinol, and also to synthesize N‐benzyl‐3‐fluoroquinolone in three steps from commercially available 2‐vinylaniline in 44 % overall yield. Also 3‐fluorocoumarin and 3‐fluorochromene were prepared from o‐vinylphenol, and 3‐fluoro‐benzoxepine was available from o‐allylphenol.
Complexation Phenomena and Dynamics at Work in the Lithiation Reactions of Small‐Ring Heterocycles: Regio‐ and Stereoselectivity
Authors: Capriati Vito , Florio Saverio , Luisi Renzo 
Published: August 2014

AbstractThis Microreview focuses on the regio‐ and stereoselective lithiation of small‐ring heterocycles such as aryl‐substituted oxiranes, aziridines, azetidines, oxetanes, and tetrahydrofurans highlighting some useful selected synthetic applications extracted from recent literature. It will be shown, in particular, that regio‐ and stereoselectivity and the configurational stability of the above lithiated species are controlled by a subtle interplay of factors. Aggregation, complexation phenomena, dynamics at the heteroatom of the heterocyclic ring, substitution in both the aryl and the heterocyclic ring, solvent polarity, temperature, and ligands play a crucial role. The ability of the afore‐mentioned heterocycles as important directed metalation groups for the areneortho‐functionalization is also discussed as well as the carbene‐like nature exhibited by some lithiated epoxides and aziridines.
Delayed atrophy in posterior cingulate cortex and apathy after stroke
Authors: Matsuoka Kiwamu , Yasuno Fumihiko , Taguchi Akihiko , Yamamoto Akihide , Kajimoto Katsufumi , Kazui Hiroaki , Kudo Takashi , Sekiyama Atsuo , Kitamura Soichiro , Kiuchi Kuniaki , Kosaka Jun , Kishimoto Toshifumi , Iida Hidehiro , Nagatsuka Kazuyuki 
Published: August 2014

ObjectiveA few studies have been performed on chronic structural changes after stroke. The primary purpose of the present study was to investigate regional cortical volume changes after the onset of stroke and to examine how the cortical volume changes affected neuropsychiatric symptoms.MethodsParticipants were 20 stroke patients and 14 control subjects. T1‐MRI was performed twice, once at the subacute stage and again 6 months later, and whole brain voxel‐based morphometric (VBM) analysis was used to detect significant cortical gray matter volume changes in patients. We also assessed the correlation between changes in cortical volumes and changes in neuropsychiatric symptoms during the 6 months following a stroke.ResultsIn the present study, we found significant volume reductions in the anterior part of the posterior cingulate cortex (PCC) over the 6 months following a stroke by exploratory VBM analysis. We also found that the amount of volume change was significantly correlated with the change in apathy‐scale scores during the 6 months poststroke.ConclusionsThe present study suggests that delayed atrophic change is evident in the PCC 6 months after a stroke. There was greater apathetic change in the stroke patients with the larger volume reductions. The delayed atrophy of the PCC may reflect degeneration secondary to neuronal loss due to stroke. Such degeneration might have impaired control of goal‐directed behavior, leading to the observed increase in apathy. Copyright © 2014 John Wiley & Sons, Ltd.
Warfarin usage among elderly atrial fibrillation patients with traumatic injury, an analysis of United States Medicare fee‐for‐service enrollees
Authors: Liu Xinggang , Baumgarten Mona , Smith Gordon , Gambert Steven , Gottlieb Stephen , Rattinger Gail , Albrecht Jennifer , Langenberg Patricia , Zuckerman Ilene 
Published: August 2014

AbstractThis study examined warfarin usage for elderly Medicare beneficiaries with atrial fibrillation (AF) who suffered traumatic brain injury (TBI), hip fracture, or torso injuries. Using the 5% Chronic Condition Data Warehouse administrative claims data, this study included fee‐for‐service Medicare beneficiaries who had a single injury hospitalization (TBI, hip fracture, or major torso injury) between 1/1/2007 and 12/31/2009, with complete Medicare Parts A, B (no Medicare Advantage), and D coverage 6 months before injury, and who were aged 66 years or older and diagnosed with AF at least 1 year before injury. About 45% of the AF patients were using warfarin before TBI or torso injury, and 35% before hip fracture. After injury, there was a dramatic and persistent decrease in warfarin use in TBI and torso injury groups (30% for TBI and 37% for torso injury at 12 months after injury). Warfarin usage in hip fracture patients also dropped after injury but returned to pre‐injury level within 4 months. TBI and torso injury lead to significant decreases in warfarin usage in elderly AF patients. Further research is needed to understand reasons for the pattern and to develop evidence‐based management strategies in the post‐acute setting.