bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conformational requirement on peptides to exert laminin's activities and search for protein segments with laminin's activities
Authors: Umezawa Koji , Ikebe Jinzen , Nomizu Motoyoshi , Nakamura Haruki , Higo Junichi 
Published: January 2009

AbstractThe human laminin α3 chain LG4 module has biological activities of cell adhesion, heparin binding, migration, and neurite outgrowth. The authors had previously identified that the active site of this protein is in residues 1411–1429 (amino‐acid sequence = KNSFMALYLSKGRLVFALG called A3G756) and that a three‐amino‐acid sequence KGR in A3G756 is crucial for exerting the activities. An experiment has shown that a cyclo‐hEF3A peptide (a cyclic analog of A3G756) exhibits stronger activities than a linear‐hEF3A peptide (a linearized peptide of the cyclo‐hEF3A peptide). This experiment implies that adopting a loop conformation may be important for exerting the activities. In this study, the authors first computed the solution structures of the cyclo‐hEF3A and linear‐hEF3A peptides by molecular dynamics simulations. The obtained conformational ensembles consisted of a variety of conformations, which is a usual property of short peptides in solution. The ensembles involved a fraction where the peptide adopted β‐hairpins and KGR was located at the hairpin head. If there are protein segments that adopt β‐hairpins similar to those sampled from the simulation and have the KGR sequence at the hairpin head, these segments may have some activities. Then, the authors searched a database for segments satisfying these requirements and detected six functional segments. Three of them had laminin's activity, and the remaining three had activities similar to laminin's activities. Analyses on the conformational ensembles of cyclo‐ and linear‐hEF3A peptides suggest that not only the KGR position in the hairpin but also the inter‐strand packing is important for exerting laminin's activities. © 2009 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 92: 124–131, 2009.This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Compositions of Essential Oils and Trichomes of Teucrium chamaedrys L. subsp. trapezunticumRech. fil. and subsp. syspirense (C. Koch) Rech. fil.
Authors: Kaya Ayla , Demirci Betül , Başer K. Hüsnü C. 
Published: January 2009

Abstractmagnified imageTeucrium chamaedrys L. is a member of the Lamiaceae family and is represented in the Flora of Turkey by six subspecies. The aerial organs of T. chamaedrys L. subsp. trapezunticum Rech. fil. and subsp. syspirense (C. Koch) Rech. fil. bears numerous eglandular and glandular trichomes. Eglandular trichomes are simple, long‐multicellular with cuticular micropapillae, and glandular hairs are of peltate and capitate types. The peltate hairs consist of a basal cell, a short unicellular stalk, and multicellular secretory head, and the capitate ones possess 1–2 stalk cells and one glandular head cell. The aerial parts were subjected to microdistillation for the isolation of volatiles. The analysis was simultaneously performed by using gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS). The major components were characterized as β‐caryophyllene (18%), nonacosane (12%), germacrene D (11%), caryophyllene oxide (7%), and α‐pinene (7%) for subsp. trapezunticum, and caryophyllene oxide (23%), α‐pinene (11%), and caryophyllenol II (5%) for subsp. syspirense.
A Simple and ‘Green’ Synthesis of Polymer‐Based Silver Colloids and Their Antibacterial Properties
Authors: Bo Lili , Yang Wu , Chen Miao , Gao Jinzhang , Xue Qunji 
Published: January 2009

Abstractmagnified imageStable silver colloids were prepared using polyethylene glycol (PEG) as an environment friendly reduction agent and stabilizer, and with H2O as solvent. The Ag colloids were characterized by UV/VIS spectroscopy, transmission electron microscopy (TEM), and atom force microscopy (AFM). TEM and AFM of the sample showed uniform and monodispersive particle distribution in the colloids. The particle size is found to be less than 10 nm. The antibacterial activity of the Ag colloids was also studied. The results showed that the sample had high antibacterial activity toward Gram‐positive and Gram‐negative bacteria, and fungi.
Deterministic and Probabilistic Estimation of Appropriate Distances: Motivation for Considering the Consequences for Industrial Sites
Authors: Gawlowski M. , Hailwood M. , Vela I. , Schönbucher A. 
Published: January 2009

AbstractAccidents and disruptions in chemical process installations can, in principle, lead to the rare events in which the release of flammable and/or toxic substances occurs, and which at particular distances from the installation can result in a hazard potential due to thermal radiation, blast wave effects or the concentration of toxic substances. The possibilities and limits of deterministic and probabilistic estimation methods for appropriate distances from hazardous installations, based on the example of an ammonia release and a large surface fire, are shown. In this, it is demonstrated that the deterministic and probabilistic approaches are in no way conflicting or unnecessary, but rather that they are complementary. The use of a deterministic estimation method leads to a maximum set radius of effects which only take account of the damage impact. Depending on the selection of the appropriate and suitable consequence models, critical distances are calculated which are in some cases much larger than the current standardised distances, as is shown by the example of large‐scale fires. The use of a probabilistic estimation method leads to a range of distances for which the individual risk can be given in addition. In principle, iso‐contours joining points of same risk or areas of same risk may be defined through the use of such estimations.
Protonation of 2H‐Azaphosphirene Complexes: PN Bond Activation and Ring‐Expansion Reactions
Authors: Helten Holger , Engeser Marianne , Gudat Dietrich , Schilling Reinhold , Schnakenburg Gregor , Nieger Martin , Streubel Rainer 
Published: January 2009

AbstractPN bond activation of 2H‐azaphosphirene complexes 1 and 2 by using triflic acid led to ring expansion in the presence of nitriles. In the absence of nitriles, the reaction surprisingly afforded two haptomeric N‐protonated 1‐aza‐3‐phospha‐butadiene complexes in the case of complex 1, whereas the N‐protonated 2H‐azaphosphirene complex [H‐2]+ was characterized by NMR spectroscopy.magnified imageProtonation of 2H‐azaphosphirene complexes 1 and 2 using trifluoromethanesulfonic acid in the presence and in the absence of nitriles was studied. Reactions with nitrile derivatives of different nucleophilicity and steric demand (3 a–f) led to highly bond‐ and regioselective ring‐expansion reactions of complexes 1 and 2 and yielded 2H‐1,4,2‐diazaphosphole complexes 4 a–f and 5 a after deprotonation with NEt3. Upon protonation of complex 1 in the absence of nitriles a mixture of two haptomeric N‐protonated 1‐aza‐3‐phosphabuta‐1,3‐diene complexes 13 and 14 was obtained, which upon addition of Me2NCN (3 a) and NEt3 afforded 2H‐1,4,2‐diazaphosphole complex 16 a bearing a P‐substituent with only one SiMe3 group. Protonation of complex 2 led to the 2H‐azaphosphirenium complex [H‐2]+, unambiguously identified by NMR spectroscopy at low temperature. All isolated products were characterized by multinuclear NMR spectroscopy, IR, MS, and single‐crystal X‐ray crystallography in the cases of complexes 4 a, 4 e, 6 a, and 16 a. Furthermore, ESI‐MS/MS studies on primarily formed reactive intermediates and DFT studies on the reaction mechanism are presented.
Stereoselective Synthesis of 2,6‐Disubstituted Piperidines Using the Iridium‐Catalyzed Allylic Cyclization as Configurational Switch: Asymmetric Total Synthesis of (+)‐241 D and Related Piperidine Alkaloids
Authors: Gnamm Christian , Krauter Caroline M. , Brödner Kerstin , Helmchen Günter 
Published: January 2009

AbstractPressing the configurational switch: Use of enantiomeric Ir catalysts allows the vinylpiperidine building blocks 2 a and 2 b to be synthesized with high selectivity. Total syntheses of the dendrobate alkaloid (+)‐241 D, its C6‐epimer, and a spruce alkaloid are presented as applications.magnified image
ortho‐Selective Phenol‐Coupling Reaction by Anodic Treatment on Boron‐Doped Diamond Electrode Using Fluorinated Alcohols
Authors: Kirste Axel , Nieger Martin , Malkowsky Itamar M. , Stecker Florian , Fischer Andreas , Waldvogel Siegfried R. 
Published: January 2009

AbstractEnlarged scope by fluorinated mediators: Oxyl radicals are easily formed on boron‐doped diamond (BDD) electrodes and can be exploited for the ortho‐selective coupling to the corresponding biphenols (see scheme). At partial conversion, a clean transformation is achieved that can be applied to electron‐rich as well as fluorinated phenols.magnified image
Helical Hairpin Structure of a Potent Antimicrobial Peptide MSI‐594 in Lipopolysaccharide Micelles by NMR Spectroscopy
Authors: Bhunia Anirban , Ramamoorthy Ayyalusamy , Bhattacharjya Surajit 
Published: January 2009

AbstractEssential understanding: Elucidation of structural requirements and interactions of antimicrobial peptides with lipopolysaccharide (LPS) are essential to understand the mechanism of action of antimicrobial peptides. The highly active antimicrobial peptide MSI‐594 (see figure for electrostatic potential surface) acquires a novel helical hairpin structure in complex with LPS. The structure and interactions of MSI‐594 with LPS presented here provide important insights into the mechanism of outer membrane permeabilization by antimicrobial peptides.magnified image
Dependency and self‐criticism in post‐partum depression and anxiety: a case control study
Authors: Vliegen Nicole , Luyten Patrick 
Published: January 2009

AbstractThis study investigates the role of self‐criticism and dependency in inpatient post‐partum depressed women (n = 55) and non‐depressed controls (n = 37) as well as the relationship between both personality dimensions and severity of depression and anxiety. As expected, mothers with post‐partum depression showed not only increased levels of depression but also anxiety compared with non‐depressed mothers. Furthermore, they had significantly higher levels of self‐criticism, but not of dependency. In the post‐partum depressed mothers, both personality dimensions were positively associated with severity of depression. However, in non‐depressed mothers, self‐criticism was positively associated with depression, while there was an inverse relationship between dependency and severity of depression. In both samples, self‐criticism, but not dependency, was related to state anxiety. The cross‐sectional nature of this study limits the ability to draw causal conclusions. The study was based on self‐report and conducted in relatively small samples. Copyright © 2009 John Wiley & Sons, Ltd.
Adult attachment as mediator between recollections of childhood and satisfaction with life
Authors: Hinnen Chris , Sanderman Robbert , Sprangers Mirjam A. G. 
Published: January 2009

AbstractIn accordance with attachment theory, the present study investigates whether internal working models of attachment mediated the association between childhood memories and satisfaction about life in adulthood. A convenient sample of 437 participants completed questionnaires assessing a broad range of childhood memories, working models of attachment and life satisfaction. After controlling for demographics, relational status and living condition, Baron and Kenny's mediation criteria were met for the association between memories about childhood, adult attachment and life satisfaction. That is, family warmth and harmony and parental support were associated with attachment security while parental rejection and adverse childhood events (e.g., abuse, parental psychopathology) were associated with an insecure attachment style. More securely attached individuals were in turn more satisfied about their current life than insecurely attached individuals. Sobel test confirmed these findings. These finding are in accordance with attachment theory and highlight the importance of this theory for understanding how early childhood experiences may impact adult life. Copyright © 2008 John Wiley & Sons, Ltd.
Proliferation of weakly suppressive regulatory CD4+ T cells is associated with over‐active CD4+ T‐cell responses in HIV‐positive patients with mycobacterial immune restoration disease
Authors: Seddiki Nabila , Sasson Sarah C. , Santner‐Nanan Brigitte , Munier Meeling , van Bockel David , Ip Susanna , Marriott Debbie , Pett Sarah , Nanan Ralph , Cooper David A. , Zaunders John J. , Kelleher Anthony D. 
Published: January 2009

AbstractThe role of Treg in patients with late‐stage HIV disease, who commence combination antiretroviral therapy (cART) and develop pathogen‐specific immunopathology manifesting as immune restoration disease (IRD) remains unclear. We hypothesised that Treg could be defective in either numbers and/or function and therefore unable to ensure the physiological equilibrium of the immune system in patients with IRD. Phenotypic and functional CD4+ T‐cell subsets of eight late‐stage HIV patients with nadir CD4 count <50 cells/μL, who developed mycobacterial IRD upon commencing cART were compared with six therapy naive HIV+ patients (nadir CD4 count <50 cells/μL), who did not develop an IRD after cART. Mycobacterium‐avium‐specific CD4+ T cells from IRD patients produced high levels of IFN‐γ and IL‐2 compared with controls (p<0.001). Surprisingly, we found a significant expansion of CD127loFoxp3+CD25+ Treg in IRD patients and a higher ratio of Treg to effector/memory subsets (p<0.001). In vitro suppression assays demonstrated reduced functional capacity of suppressor cells and diminished IL‐10 secretion in IRD patients. Plasma levels of IL‐7 were increased in patients and, interestingly, exogenous IL‐7 and other cytokines strongly inhibited Treg suppression. These data suggest that despite substantial Treg expansion in IRD, their ability to induce suppression, and thereby downregulate aberrant immune responses, is compromised.
A Study of the Influence of Composition on the Microstructural Properties of ZnO/Al2O3 Mixed Oxides
Authors: Miao Shaojun , d'Alnoncourt Raoul Naumann , Reinecke Thomas , Kasatkin Igor , Behrens Malte , Schlögl Robert , Muhler Martin 
Published: January 2009

AbstractA series of ZnO/Al2O3 mixed oxide samples with varyingZn/Al ratio is prepared by coprecipitation, ageing, drying, and calcination. Samples are investigated in the state after drying and calcination. The applied methods include X‐ray diffraction, solid‐state 27Al magic‐angle spinning nuclear magnetic resonance spectroscopy, transmission electron microscopy and thermogravimetric experiments coupled with evolved gas analysis. Phases present in the dried precursor samples include hydrozincite, zaccagnaite, and an unknown phase. After calcination zinc oxide and spinel can be found. All results indicate the substitution of Al ions for Zn ions in zinc oxide of zinc‐rich samples. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Low‐Barrier Pathway for endo‐Cleavage Induced Anomerization of Pyranosides with N‐Benzyl‐2,3‐trans‐oxazolidinone Groups
Authors: Satoh Hiroko , Hutter Jürg , Lüthi Hans Peter , Manabe Shino , Ishii Kazuyuki , Ito Yukishige 
Published: January 2009

AbstractPyranosides with N‐benzyl‐2,3‐trans‐oxazolidinone undergo anomerization from the β form to the α form even in the presence of a weak Lewis acid. Experimental evidence for endo‐cleavage, the breaking of the bond between the pyran‐oxygen and anomeric carbon atoms, in the anomerization reactions was obtained. This unexpected phenomenon was investigated by quantum mechanical calculations, which found clear differences in the transition states between anomerized and non‐anomerized substrates. The computations suggest that BF3 induces endo‐cleavage followed by rotation of the C1–C2 bond to give the α form via lower‐energy transition states. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Making Molecules Make Themselves – the Chemistry of Artificial Replicators (Eur. J. Org. Chem. 5/2009)
Authors: Vidonne Annick , Philp Douglas 
Published: January 2009

AbstractThe cover picture shows in the lower left corner the schematic representation of a recognition‐mediated autocatalytic cycle that is capable of producing multiple copies of a single molecule in a template‐directed manner. The molecular recognition inherent in this cycle (red) leads to the accelerated formation of an imine bond (blue) between two building blocks through a ternary complex that renders the reaction between them pseudointramolecular. After bond formation, the product duplex dissociates and returns two molecules to the start of the autocatalytic cycle. The structure in the upper right corner represents the product duplex as determined by single‐crystal X‐ray diffraction ([18·18], taken from ref.[28]). The multiple copies of the reaction product shown highlight the exponential increase in the concentration of the product inherent in self‐replicating systems. Details are presented in the Microreview by A. Vidonne and D. Philp on p. 593 ff.
Electrochemical Detection of Cadmium and Lead Complexes with Low Molecular Weight Organic Acids
Authors: Dytrtová Jana Jaklová , Šestáková Ivana , Jakl Michal , Navrátil Tomáš 
Published: January 2009

AbstractThe Cd and Pb complexes with oxalic (OA) and citric acid (CA) were detected in model and soil solutions using cyclic and stripping voltammetry. A mixed complex consisting of Cd, Pb, and OA was found; its peak potential varied from −582.0 to −542.5 mV (vs. Ag/AgCl/KCl(3 mol L−1)). For mixed complex formation, the presence of PbOH+ species and Cd2+ in oxalic acid solution was necessary. Only the ‘simple’ complexes of CA with Pb and Cd were found in the model solution. The existence of all investigated metal complexes is confined to neutral pH range. The mixed complex was also found in real soil solutions.
Electrochemical Nanobiosensor for Glyphosate Herbicide and Its Metabolite
Authors: Songa Everlyne A. , Waryo Tesfaye , Jahed Nazeem , Baker Priscilla G. L. , Kgarebe Boitumelo V. , Iwuoha Emmanuel I. 
Published: January 2009

AbstractThe use of amperometric biosensor for the detection of glyphosate herbicide and its metabolite aminomethylphosphonic acid (AMPA) is presented. The biosensor was developed by electrochemically depositing poly(2,5‐dimethoxyaniline) (PDMA) doped with poly(4‐styrenesulfonic acid) (PSS) onto the surface of a gold electrode followed by electrostatic attachment of horseradish peroxidase (HRP) onto the PDMA‐PSS nanocomposite film. The PDMA‐PSS film was characterized by transmission electron microscopy (TEM) and Fourier Transform infrared (FTIR) spectroscopy. The HRP immobilized on the PDMA‐PSS film catalyzed the reduction of hydrogen peroxide, the inhibition of which was applied in the detection of glyphosate and AMPA. The limits of detection of the biosensor for glyphosate and AMPA were 0.16 μg L−1 and 1.0 μg L−1, respectively. The study demonstrates that the biosensor is very sensitive and could be a useful tool in the screening of glyphosate and AMPA at low concentrations.
Preparation and characterization of temperature‐responsive capillary electrochromatographic column using poly(N‐isopropylacrylamide)
Authors: Dai Rongji , Zhang Xuejing , Hu Na , Liu Yueying , Deng Yulin 
Published: January 2009

AbstractPoly(N‐isopropylacrylamide) is a temperature‐responsive polymer, which is hydrophilic at low temperature but hydrophobic at high temperature. Using this characteristic, the polymer was bonded to the inner surface of fused‐silica capillary to prepare a temperature‐responsive column to study the separation behavior in electrochromatography.
Fact learning in complex arithmetic and figural‐spatial tasks: The role of the angular gyrus and its relation to mathematical competence
Authors: Grabner Roland H. , Ischebeck Anja , Reishofer Gernot , Koschutnig Karl , Delazer Margarete , Ebner Franz , Neuper Christa 
Published: January 2009

AbstractNeuroimaging studies have revealed a strong link between mental calculation and the angular gyrus (AG) which has been interpreted to reflect arithmetic fact retrieval. Moreover, a stronger AG activation in individuals with higher mathematical competence has been reported. The present fMRI study investigates the specificity of the AG for arithmetic fact learning and the interplay between training and mathematical competence on brain activation. Adults of lower and higher mathematical competence underwent a five‐day training on sets of complex multiplication and figural‐spatial problems. In the following fMRI test session, trained and untrained problems were presented. Similar training effects were observed in both problem types, consisting of AG activation increases bilaterally and wide‐spread activation decreases in frontal and parietal regions. This finding indicates that the AG is not specifically involved in the learning of arithmetic facts. Competence‐related differences in the AG only emerged in untrained but not in trained multiplication problems. The relation between AG activation and mathematical competence in arithmetic problem solving therefore seems to be due to differences in arithmetic fact retrieval which can be attenuated through training. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
ICA decomposition of EEG signal for fMRI processing in epilepsy
Authors: Marques José P. , Rebola José , Figueiredo Patrícia , Pinto Alda , Sales Francisco , Castelo‐Branco Miguel 
Published: January 2009

AbstractIn this study, we introduce a new approach to process simultaneous Electroencephalography and functional Magnetic Resonance Imaging (EEG‐fMRI) data in epilepsy. The method is based on the decomposition of the EEG signal using independent component analysis (ICA) and the usage of the relevant components' time courses to define the event related model necessary to find the regions exhibiting fMRI signal changes related to interictal activity. This approach achieves a natural data‐driven differentiation of the role of distinct types of interictal activity with different amplitudes and durations in the epileptogenic process. Agreement between the conventional method and this new approach was obtained in 6 out of 9 patients that had interictal activity inside the scanner. In all cases, the maximum Z‐score was greater in the fMRI studies based on ICA component method and the extent of activation was increased in 5 out of the 6 cases in which overlap was found. Furthermore, the three cases where an agreement was not found were those in which no significant activation was found at all using the conventional approach. Hum Brain Mapp 2009. © 2009 Wiley‐Liss, Inc.
Five New Cassane‐Type Diterpenes from Caesalpinia crista
Authors: Yang Zheng‐Yi , Yin Yin‐Hua , Hu Li‐Hong 
Published: January 2009

Abstractmagnified imageFive new cassane‐type diterpenes, caesalpinista A (1), caesalpinista B (2), caesaljapin B (3), caesaljapin C (4), and caesalpinilinn (5) were isolated from the MeOH extract of the seeds of Caesalpinia crista. Their structures were elucidated by the analysis of their 1D‐ and 2D‐NMR spectra.