bluuebunny/crossref_metadata_2025 huggingface dataset:
Surveillance of Adenovirus D in patients with epidemic keratoconjunctivitis from Fukui Prefecture, Japan, 1995–2010
Authors: Nakamura Masako , Hirano Eiko , Kowada Kazuaki , Ishiguro Fubito , Yamagishi Zenya , Adhikary Arun Kumar , Hanaoka Nozomu , Okabe Nobuhiko , Taniguchi Kiyosu , Fujimoto Tsuguto
Published: November 2011

Human adenoviruses species D (HAdV‐D) are known to cause severe epidemic keratoconjunctivitis. However, the isolation rate of HAdV‐D is not high, because HAdV‐D is usually slow to propagate. Although new types of HAdV‐D have been reported, accurate surveillance has not been performed because of difficulties in culturing the viruses and lack of a practical identification method. In this study, HAdV‐Ds were detected and identified from patients with epidemic keratoconjunctivitis in the Fukui Prefecture during 1995–2010 by PCR, loop‐mediated isothermal amplification (LAMP) of DNA, and conventional virus isolation and neutralization tests. All samples were subjected to culture and PCR and LAMP. A total of 124 strains of HAdV‐D were detected from 157 patients with epidemic keratoconjunctivitis. The strains consisted of the following types: D8 (n = 8), D19 (n = 4), D37 (n = 40), D53 (n = 5), D54 (n = 66), and D56 (n = 1). Among these, D53, D54, and D56 are new types that have been reported recently. The results of this study demonstrated that new types of HAdV‐D caused epidemic keratoconjunctivitis during 1995–2010, and included an outbreak of keratoconjunctivitis caused by HAdV‐D54. The LAMP method was able to detect and identify HAdV‐D53 and HAdV–D54 in 1 hr, and may therefore be applicable for use at the bedside. J. Med. Virol. 84:81–86, 2011. © 2011 Wiley Periodicals, Inc.
Antibody persistence and immune memory in adults, 15 years after a three‐dose schedule of a combined hepatitis A and B vaccine
Authors: Van Damme P. , Leroux‐Roels G. , Crasta P. , Messier M. , Jacquet J‐M. , Van Herck K.
Published: November 2011

A combined hepatitis A and B vaccine is available since 1996. Two separate open‐label primary studies evaluated the immunogenicity and safety of this hepatitis A and B vaccine (720 EI.U of HAV and 20 µg of HBsAg) in 306 healthy subjects aged 17–43 years who received three doses of the vaccine following a 0, 1, and 6 months schedule. These subjects were followed up annually for the next 15 years to evaluate long‐term persistence of anti‐HAV and anti‐HBs antibodies. The subjects whose antibody concentrations fell below the cut‐offs between Year 11 and Year 15 (anti‐HAV: <15 mIU/ml; anti‐HBs: <10 mIU/ml) were offered an additional dose of the appropriate monovalent hepatitis A and/or B vaccine. In subjects who received the additional vaccine dose, a blood sample was collected 1 month after vaccination. At the Year 15 time point, all subjects in Study A and Study B were seropositive for anti‐HAV antibodies and 89.3% and 92.9% of subjects in the respective studies had anti‐HBs antibody concentrations ≥10 mIU/ml. Four subjects (two in each study) received an additional dose of monovalent hepatitis B vaccine and mounted anamnestic responses to vaccination. No vaccine‐related serious adverse events were reported. This study confirms the long‐term immunogenicity of the three‐dose regimen of the combined hepatitis A and B vaccine, as eliciting long‐term persistence of antibodies and immune memory against hepatitis A and B for up to at least 15 years after a primary vaccination. J. Med. Virol. 84:11–17, 2011. © 2011 Wiley Periodicals, Inc.
Effect of exogenous administration of Candida albicans autoregulatory alcohols in a murine model of hematogenously disseminated candidiasis
Authors: Martins Margarida , Lazzell Anna L. , Lopez‐Ribot Jose L. , Henriques Mariana , Oliveira Rosário
Published: November 2011

Candida albicans supernatants contain a mixture of autoregulatory alcohols. In vitro, when added individually or in combination, these alcohols inhibit the yeast to filamentous form conversion. Here we evaluate the in vivo effect of the exogenous administration of a Cocktail solution simulating the composition of alcohols present in a C. albicans culture supernatant (1 ml; 94 μmol l–1 isoamyl alcohol, 70 μmol l–1 2‐phenylethanol, 3.2 n mol l–1 E ‐nerolidol, and 18 n mol l–1 E,E ‐farnesol) using the well established murine model of hematogenously disseminated candidiasis. Mice injected intraperitoneally with the Cocktail solution demonstrated increased survival and decreased organ fungal burden compared to control mice. Histological observations suggest that the Cocktail, to some extent, has an inhibitory effect on cell filamentation within the kidney. These findings suggest that the exogenous administration of C. albicans autoregulatory alcohols displays a protective effect during disseminated candidiasis. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Genetic transformation of Colletotrichum truncatum associated with anthracnose disease of chili by random insertional mutagenesis
Authors: Auyong Adelene Shu Mei , Ford Rebecca , Taylor Paul William James
Published: November 2011

An Agrobacterium tumefaciens ‐mediated transformation (ATMT) system was successfully developed for Colletotrichum truncatum, the causal agent of chili anthracnose. A. tumefaciens carrying a hygromycin phosphotransferase gene (hph) and a green fluorescent protein (gfp) gene was used to transform the conidiospores of two C. truncatum pathotypes F8‐3B and BRIP26974. Optimum transformation efficiency was obtained when equal volumes of A. tumefaciens strain AGL1 carrying either pJF1 or pPK2 binary vector was used to transform C. truncatum conidiospores at 106/ml and co‐cultivated at 24 °C for three days. Southern blot analysis indicated that 87.5% of the transformants contained randomly inserted, single copies of the T‐DNA. Infection and colonisation of chili fruit at the mature red stage with F8‐3B‐GFP and BRIP26974‐GFP confirmed the maintenance of virulence within these transformed pathotypes. In situ studies of infection and colonisation of the susceptible genotype fruit using fluorescent microscopy and transformed isolates of C. truncatum expressing GFP revealed that the pathogen was able to colonise healthy fruit tissue intercellularly in an endophytic manner without producing secondary biotrophic infection structures. The developed transformation system will be used to study the function of pathogenicity genes in C. truncatum using both forward and reverse genetics approaches. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Purification and characterization of a xylanase from Bacillus subtilis isolated from the degumming line
Authors: Guo Gang , Liu Zhengchu , Xu Junfei , Liu Jianping , Dai Xiaoyang , Xie Daping , Peng Keqing , Feng Xiangyuan , Duan Shengwen , Zheng Ke , Cheng Lifeng , Fu Yueguan
Published: November 2011

Xylanases catalyze the hydrolysis of xylan, a major hemicellulose component of cell wall besides cellulose in most plant species. To extract cellulose fibers, it will be invaluable to screen for more effective xylanase‐producing microorganisms. In this paper a new strategy for easy screening of xylanase‐producing strains from the degumming line was presented. Using this strategy, a weak‐acidic, cellulase‐free xylanase from Bacillus subtilis has been isolated, purified and characterized. The xylanase showed high specific activity (36,633.4 U/mg), presented stable characteristics and can be separated and purified simply, with molecular weight 23.3 kD, pI 9.63. It reached its optimal activity at pH 5.8 and 60 °C, and retained over 80% of its maximal activity after pre‐incubation at temperature 60 °C or pH 4.6 ∼ 6.4. Also, a two‐step purification procedure based on the combination of ultrafiltration and gel filtration chromatography was introduced and described, achieving 17‐fold purification with 68.11% yield. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Tuning of phonon anharmonicity in pyrochlore titanates: temperature‐dependent Raman studies of Sm2Ti2‐xZrxO7 (x=0, 1/2, 3/4, and 2) and stuffed spin‐ice Ho2 + xTi2 − xO7 − x/2 (x=0, 1/3, and 2/3)
Authors: Saha Surajit , Prusty Sudakshina , Singh Surjeet , Suryanarayanan R. , Revcolevschi A. , Sood A. K.
Published: November 2011

Anomalous temperature dependence of Raman phonon wavenumbers attributed to phonon–phonon anharmonic interactions has been studied in two different families of pyrochlore titanates. We bring out the role of the ionic size of titanium and the inherent vacancies of pyrochlore in these anomalies by studying the effect of replacement of Ti4 + by Zr4 + in Sm2Ti2O7 and by stuffing Ho3 + in place of Ti4 + in Ho2Ti2O7 with appropriate oxygen stoichiometry. Our results show that an increase in the concentration of the larger ion, i.e. Zr4 + or Ho3 +, reduces the phonon anomalies, thus implying a decrease in the phonon–phonon anharmonic interactions. In addition, we find signatures of coupling between a phonon and crystal field transition in Sm2Ti2O7, manifested as an unusual increase in the phonon intensity with increasing temperature. Copyright © 2011 John Wiley & Sons, Ltd.
Raman spectrum of monobromoindigo
Authors: Ajiki Hiroko , Pozzi Federica , Huang Lulu , Massa Lou , Leona Marco , Lombardi John R.
Published: November 2011

Monobromoindigo is a component of Tyrian purple, a purple–red natural colorant extracted from various species of sea snails, which was possibly first produced by the ancient Phoenicians and has been employed as a symbol of royalty and power by several civilizations over the centuries. Raman spectroscopy has proved to be an effective analytical technique to detect historical dyes, as it allows rapid and accurate identification of unknowns in a nondestructive way. Although other constituents of Tyrian purple have been comprehensively investigated by Raman spectroscopy, the Raman bands of 6‐bromoindigo, a molecule that has been correlated with a specific snail species, Hexaplex trunculus (also known as Murex trunculus), have been reported but not previously assigned. This paper includes a complete assignment of the Raman spectrum of the 6‐bromoindigo isomer, including experimental spectra recorded at 488 and 785 nm, which were compared with those collected from indigo under the same conditions. Theoretical Raman spectra for both molecules were obtained using density functional theory calculations. Copyright © 2011 John Wiley & Sons, Ltd.
Au nanoplate/polypyrrole nanofiber composite film: preparation, characterization and application as SERS substrate
Authors: Xia Youyi , Xiao Hongping
Published: November 2011

Without any other additives or additional energy, Au nanoplates have been successfully prepared and integrated simultaneously with the dedoped polypyrrole nanofiber film via the in situ reduction of AuCl4– on the film surface. The morphology and structure of the as‐prepared composite film are characterized, and its application for surface‐enhanced Raman scattering is also investigated. It has been found that the morphology of as‐prepared Au nanoplates is dependent on the reaction duration, while the density is dependent on the concentration of AuCl4– ions in the reaction process. It is suggested that polypyrrole plays dual reducing and structure‐directing roles during the formation of Au nanoplates. Surface‐enhanced Raman scattering study shows that the Au nanoplates give an intensive and enhanced Raman scattering when 4‐aminothiophenol is used as a probing molecule. The employed approach may shed some light on simultaneously fabricating and immobilizing other noble metal micro/nanostructures with unique morphology. Copyright © 2011 John Wiley & Sons, Ltd.
Micro‐Raman and photoluminescence analysis of composite vanadium oxide/poly‐vinyl acetate fibres synthesised by electro‐spinning
Authors: Faggio G. , Modafferi V. , Panzera G. , Alfieri D. , Santangelo S.
Published: November 2011

Composite vanadium oxide (VOx)‐based fibres were synthesised by the electro‐spinning method combined with conventional sol–gel processing using polyvinyl acetate (PVAc) as a polymeric binder and vanadium oxytriisopropoxide as a vanadium oxide precursor. The microstructure and composition of as‐spun and calcined (300–500 °C) VOx–PVAc fibres were systematically investigated by scanning electron microscopy, thermogravimetry, reflectance infrared Fourier transform, micro‐Raman spectroscopy and photoluminescence in view of their possible use in gas sensor fabrication. The comparative discussion of the characterization results indicates that V2O5–PVAc fibres are obtained. Calcination gradually removes PVAc and promotes structural rearrangement with consequent fibre‐morphology changes. With increasing calcination temperature, the crystallinity degree of V2O5 improves and a more oxygen‐deficient substoichiometric surface layer forms. Calcination at 400 °C preserves the fibre integrity. Indeed, fibres calcined at this temperature appear as the most suitable ones for use as the active layer in gas‐sensing devices. Copyright © 2011 John Wiley & Sons, Ltd.
Identification of the a kinase anchor protein 12 (AKAP12) gene as a candidate tumor suppressor of hepatocellular carcinoma
Authors: Hayashi M , Nomoto S , Kanda M , Okamura Y , Nishikawa Y , Yamada S , Fujii T , Sugimoto H , Takeda S , Kodera Y
Published: November 2011

Background

Hepatocellular carcinoma (HCC) is a major health problem, and identification of new tumor‐related genes is an urgent task.

Methods

To detect tumor‐related genes effectively, we performed double‐combination array analysis, which consisted of an expression array and a single nucleotide polymorphism (SNP) array of a single surgical HCC specimen.

Results

Expression array analysis identified AKAP12 as one of the genes with reduced expression in HCC tissues when compared with non‐cancerous adjacent hepatic tissues. In addition, AKAP12 expression levels in tumor tissues from 48 HCC samples were significantly lower (P < 0.001) than those in normal tissues, and the downregulation was significantly correlated with poor overall survival rate (P = 0.003). However, SNP array analysis revealed that locus 6q24‐q25 where AKAP12 was located did not show chromosomal deletion. In contrast, hypermethylation in the AKAP12 promoter regions was observed in 41 of 48 HCC samples. We then confirmed that AKAP12 gene re‐expression occurs after 5‐aza‐2′‐deoxycytidine (5‐aza‐dC) treatment through direct sequence analysis of the AKAP12 promoter region in HCC cell lines.

Conclusions

The current data suggest that AKAP12 is downregulated in cancer tissues through promoter hypermethylation, and may have a role as a candidate tumor suppressor gene for HCC. J. Surg. Oncol. 2012;105:381–386. © 2011 Wiley Periodicals, Inc.
Determination of ethylene glycol dinitrate in dynamites using HPLC: Application to the plastic explosive Goma‐2 ECO
Authors: Sáiz Jorge , Bravo Juan Carlos , Ávila Esperanza Velasco , Torre Mercedes , García‐Ruiz Carmen
Published: November 2011

In this study, a sequential extraction method using water and methanol to recover ethylene glycol dinitrate or nitroglycol (EGDN) contained in Goma‐2 ECO dynamite was developed. After, an HPLC method was used for the determination of EGDN in the two extracted phases. The analytical method was validated by evaluating its selectivity, sensitivity, linearity, and linear working concentration range, limit of detection and quantitation, precision (as repeatability and intermediate precision), accuracy, and robustness, providing appropriate values (i.e. RSD values for precision about 6% and accuracy about 100%). Finally, the EGDN content of a sample of the Goma‐2‐ECO dynamite was determined obtaining a concentration of 30.29%, which is in accordance with the manufacturer's specifications for this dynamite (25.7–31.4%).
Preparation, characterization and application of a new stir bar sorptive extraction based on poly(vinylphthalimide‐co‐N,N′‐methylenebisacrylamide) monolith
Authors: Huang Xiaojia , Chen Linli , Yuan Dongxing , Luo Xianbin
Published: November 2011

In this study, a new stir bar sorptive extraction (SBSE) coating based on poly(vinylphthalimide‐co‐N,N′‐methylenebisacrylamide) monolith (SBSE‐VPMB) was prepared. The influences of the contents of monomer in polymerization mixture and the percentage of porogen solvent on the extraction performance were investigated thoroughly. Several characteristic techniques, such as elemental analysis, scanning electron microscopy, mercury intrusion porosimetry and infrared spectroscopy, were used to characterize the monolithic material. The analysis of oxfendazole (OFZ) and mebendazole (MBZ) in milk and honey samples by the combination of SBSE with HPLC with diode array detection was selected as paradigms for the practical evaluation of the new coating. Under the optimized extraction conditions, the limits of detection (S/N=3) for OFZ and MBZ were 0.23–0.60 μg/L in milk and 0.24–1.08 μg/L in honey, respectively. The method also showed good linearity, repeatability, high feasibility and acceptable recoveries for real samples. At the same time, the extraction performance and the distribution coefficients (KVPMB/W) of OFZ and MBZ on SBSE‐VPMB were compared with other SBSEs based on porous monoliths and commercial SBSE.
Photocatalytic Activity of Epoxy/CNT Nanocomposite Films
Authors: Sangermano Marco , Pinneri Stefano , Calza Paola , Paganini Cristina
Published: November 2011

The efficiency of epoxy/CNT nanocomposites as photocatalyst on adsorbed, aqueous and gas phases is investigated. Epoxy films containing SWNTs in the range between 0.1 and 0.3 wt% are prepared by means of UV‐induced polymerization and the achieved materials are used as photocatalysts on adsorbed, aqueous, and gas phases. The activity of this new photocatalytic materials is evaluated in the adsorbed state by using the methylene blue target molecule, in the aqueous phase by following the photodegradation of phenol and 3,5‐dichlorophenol, and in the gas phase using nitrogen monoxide as probe molecule. It is demonstrated that the catalyst is suitable for both oxidative and reductive degradation reactions.

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Composites of Ultrahigh‐Molecular‐Weight Polyethylene with Graphene Sheets and/or MWCNTs with Segregated Network Structure: Preparation and Properties
Authors: Ren Peng‐Gang , Di Ying‐Ying , Zhang Qian , Li Lan , Pang Huan , Li Zhong‐Ming
Published: November 2011

UHMWPE/MWCNT and UHMWPE/GNS composites with a segregated network are prepared. TEM and SEM images indicate that the conducting fillers are distributed on the UHMWPE surface and form a segregated conducting network. The percolation threshold of UHMWPE/GNS composites is ≈0.25 wt% and that of UHMWPE/MWCNT composites is 0.20 wt%. The electrical conductivity of UHMWPE/GNS composites is almost four orders of magnitude lower than that of the UHMWPE/MWCNT composites. For equivalent concentrations of GNS and MWCNT, the composites with hybrid fillers exhibit a lower percolation threshold and a higher conductivity than that with GNS or MWCNT alone. Due to the high strength of the fillers and the segregated network structure, the mechanical properties of the composites first increase and then decrease with increasing filler content.

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Characterization of Imprinted Microbeads Synthesized via Minisuspension Polymerization
Authors: Torres Juan J. , Montejano Hernán A. , Chesta Carlos A.
Published: November 2011

The properties of MIPs synthesized by minisuspension polymerization are studied. The template is cyclododecyl 2,4‐dihydroxybenzoate (1), which behaves as good mimic of the estrogenic mycotoxin zearalenone. 2‐DAEM and EGDMA are used as functional and crosslinker monomers, respectively. The synthesized particles are characterized by optical and electronic microscopy, N2 sorption measurements, and FT‐IR spectroscopy. The molecular recognition capability of MIPs is evaluated by comparing the adsorption Freundlich isotherms of MIPs to those of the corresponding non‐imprinted polymers. It is concluded that MSP is an attractive alternative for molecular imprinting because it is easy to apply and produces high yield of spherical particles of “tunable” size with acceptable molecular recognition capabilities.

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Modification of Rheological Properties Under Elongational Flow by Addition of Polymeric Fine Fibers
Authors: Yamaguchi Masayuki , Fukuda Keiko , Yokohara Tadashi , Ali Mohd Amran Bin Md , Nobukawa Shogo
Published: November 2011

A new technique to provide melt elasticity using flexible fine fibers prepared from a polymer with high melting point is demonstrated. A polymer composite of poly(propylene) with a small amount of fine fibers of poly(butylene terephthalate) shows marked strain‐hardening behavior in elongational viscosity, i.e., a rapid increase in the transient elongational viscosity with time or strain. The blend also shows prominent normal stress difference at steady shear. These elastic properties have not been observed for polymer composites with rigid fibers and can be applicable to the modification of rheological properties and thus the improvement of processability.

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Clarifying distal axonal properties of the median nerve
Authors: Moore Dominic , Menon Parvathi , Vucic Steve
Published: November 2011

Introduction: Although length‐dependent axonal excitability changes have been reported in the median nerve, the mechanisms underlying these changes remain to be further clarified. Methods: Axonal excitability studies were performed on median nerve at the palm and wrist in 20 healthy controls, with responses recorded over the abductor pollicis brevis. Results: The strength–duration time constant was significantly shorter (palm: 0.35 ± 0.01 ms; wrist: 0.48 ± 0.03 ms; P < 0.001), whereas rheobase was significantly increased (palm: 2.90 ± 1.12 mA; wrist: 2.09 ± 1.11 mA; P < 0.05) at the palm. In addition, there was a significant increase in depolarizing threshold electrotonus at 90–100 ms (P < 0.001) and a reduction in S2 accommodation (P < 0.001) and late subexcitability (P < 0.001) at the palm. The changes in excitability were independent of factors influencing median nerve cross‐sectional area. Conclusions: The present study reveals significant length dependent changes in median nerve excitability which may reflect differences in intrinsic membrane properties. Muscle Nerve, 2012
Application of futility analysis to refine jitter recordings in myasthenia gravis
Authors: Narayanaswami Pushpa , Pantoja‐Galicia Norberto , Betensky Rebecca A. , Rutkove Seward B.
Published: November 2011

Introduction: The current practice of single‐fiber electromyography (SFEMG) requires that 20 fiber pairs with normal jitter be collected to exclude myasthenia gravis (MG). We applied principles of futility analysis from clinical trials in an attempt to reduce that requirement. Methods: We utilized conditional power futility analysis to assess the probability of an abnormal 20‐pair SFEMG based on ongoing analysis of jitter as each pair is collected. Rules for early test termination in the presence of 0, 1, or 2 abnormal pairs were identified. These rules were then applied to previously collected SFEMG data. Results: SFEMG could be stopped at just 12 pairs if all are normal and at 17 pairs if 1 is abnormal. The rules successfully determined when SFEMG could be stopped in 104 of 106 (98%) studies originally reported to be normal. Conclusions: If the first 12 SFEMG pairs have normal jitter, the study can be terminated and interpreted as normal. Muscle Nerve, 2012
Oxidative capacity and fatigability in run‐trained malignant hyperthermia–susceptible mice
Authors: Rouviere Clement , Corona Benjamin T. , Ingalls Christopher P.
Published: November 2011

Introduction: The purpose of this study was to test the hypothesis that malignant hyperthermia model mice (RyR1Y522S/wt) are more vulnerable to exercise‐induced muscle injury and fatigability and adapt less to run training. Methods: After 6 weeks of voluntary wheel running, we measured anterior crural muscle fatigability, muscle injury, and cytochrome oxidase (COX) and citrate synthase (CS). Results: Although RyR1Y522S/wt mice ran without undergoing MH episodes, they ran 42% less distance than wild‐type (WT) mice. Muscles from WT mice exhibited increased fatigue resistance and COX content after training. Muscles from RyR1Y522S/wt mice demonstrated no significant change in fatigability or COX and CS after training. However, muscles from RyR1Y522S/wt mice displayed less intrinsic fatigability and greater COX/CS content and muscle damage than WT mice. Conclusions: RyR1Y522S/wt mice can run without having rhabdomyolysis, and their inability to adapt to training appears to stem from intrinsic enhancement of mitochondrial enzymes and fatigue resistance. Muscle Nerve, 2012
Stroboskopische Spielereien
Authors: Ucke Christian , Schlichting Hans Joachim
Published: November 2011

Der Stroboskopeffekt ist vielen Menschen aus Discos bekannt. Das Spielzeug Strobotop nutzt diesen Effekt spielerisch aus und stellt auf vorgedruckten Scheiben unterhaltsame Bildfolgen dar. Selbst erstellte Bildphasen sind ebenfalls möglich. Vorläufer des Strobotops mit den Namen Phenakistiskop und Zoetrop finden sich bereits im 19. Jahrhundert.
Licht macht Druck
Authors: Kiesel Nikolai , Wieczorek Witlef , Gröblacher Simon , Aspelmeyer Markus
Published: November 2011

Die Verbindung von Quantenoptik mit Mikro‐ und Nanomechanik in der Quanten‐Optomechanik ermöglicht es, die mechanischen Eigenschaften von massiven mechanischen Oszillatoren zu kontrollieren. Schon heute kann die Bewegung mechanischer Objekte von einigen Mikrometern Größe per Laserkühlung bis ins Quantenregime eingefroren werden. Das eröffnet völlig neue Perspektiven sowohl für makroskopische Quantenexperimente, die unser Weltbild grundlegend in Frage stellen, als auch für neue Quanteninformationstechnologien. Aktuelle Experimente versuchen bereits in ein Regime vorzudringen, in dem die mechanische Bewegung von massiven Objekten aufgrund von Quantensuperposition oder Verschränkung nicht mehr klassisch verstanden werden kann.
Ketchup‐Effekt beim Schlangengift
Authors: van Hemmen J. Leo
Published: November 2011

Gift spielt während der Beutejagd sowohl bei der Mehrzahl der Schlangen wie auch bei giftigen Reptilien eine wichtige Rolle. Es wird über gefurchte, statt hohle Zähne appliziert. Mit Hilfe experimenteller Bestimmung der Fließeigenschaften, mathematischer Modellierung sowie Computersimulationen ist es unserer Gruppe an der TU München gelungen, ein konsistentes Bild zu entwerfen, das auf Viskosität und Oberflächenspannung des Giftes beruht. Dieses Bild erklärt auf natürliche Weise das subtile Spiel, bei dem das Gift einerseits sehr zäh in der Rille und andererseits sehr geschmeidig in der aus Furche und Gewebe bestehenden Giftröhre fließt.
How noise in force fields can affect the structural refinement of protein models?
Authors: Gniewek Pawel , Kolinski Andrzej , Jernigan Robert L , Kloczkowski Andrzej
Published: November 2011

Structural refinement of predicted models of biological macromolecules using atomistic or coarse‐grained molecular force fields having various degree of error is investigated. The goal of this analysis is to estimate what is the probability for designing an effective structural refinement based on computations of conformational energies using force field, and starting from a structure predicted from the sequence (using template‐based or template‐free modeling), and refining it to bring the structure into closer proximity to the native state. It is widely believed that it should be possible to develop such a successful structure refinement algorithm by applying an iterative procedure with stochastic sampling and appropriate energy function, which assesses the quality (correctness) of protein decoys. Here, an analysis of noise in an artificially introduced scoring function is investigated for a model of an ideal sampling scheme, where the underlying distribution of RMSDs is assumed to be Gaussian. Sampling of the conformational space is performed by random generation of RMSD values. We demonstrate that whenever the random noise in a force field exceeds some level, it is impossible to obtain reliable structural refinement. The magnitude of the noise, above which a structural refinement, on average is impossible, depends strongly on the quality of sampling scheme and a size of the protein. Finally, possible strategies to overcome the intrinsic limitations in the force fields for impacting the development of successful refinement algorithms are discussed. Proteins 2012. © 2011 Wiley Periodicals, Inc.
Computational protein design with explicit consideration of surface hydrophobic patches
Authors: Jacak Ron , Leaver‐Fay Andrew , Kuhlman Brian
Published: November 2011

De novo protein design requires the identification of amino‐acid sequences that favor the target‐folded conformation and are soluble in water. One strategy for promoting solubility is to disallow hydrophobic residues on the protein surface during design. However, naturally occurring proteins often have hydrophobic amino acids on their surface that contribute to protein stability via the partial burial of hydrophobic surface area or play a key role in the formation of protein–protein interactions. A less restrictive approach for surface design that is used by the modeling program Rosetta is to parameterize the energy function so that the number of hydrophobic amino acids designed on the protein surface is similar to what is observed in naturally occurring monomeric proteins. Previous studies with Rosetta have shown that this limits surface hydrophobics to the naturally occurring frequency (∼ 28%), but that it does not prevent the formation of hydrophobic patches that are considerably larger than those observed in naturally occurring proteins. Here, we describe a new score term that explicitly detects and penalizes the formation of hydrophobic patches during computational protein design. With the new term, we are able to design protein surfaces that include hydrophobic amino acids at naturally occurring frequencies, but do not have large hydrophobic patches. By adjusting the strength of the new score term, the emphasis of surface redesigns can be switched between maintaining solubility and maximizing folding free energy. Proteins 2011. © 2012 Wiley Periodicals, Inc.
Synthesis and preliminary conformational analysis of TOAC spin‐labeled analogues of the medium‐length peptaibiotic tylopeptin B
Authors: Gobbo Marina , Merli Elisabetta , Biondi Barbara , Oancea Simona , Toffoletti Antonio , Formaggio Fernando , Toniolo Claudio
Published: November 2011

A set of analogues of the 14‐residue peptaibol tylopeptin B, containing the stable free‐radical 4‐amino‐1‐oxyl‐2,2,6,6,‐tetramethylpiperidine‐4‐carboxylic acid (TOAC) at one or two selected positions, was synthesized by the solid‐phase methodology. A solution conformational analysis performed by FTIR absorption and CD suggests that, in membrane‐mimicking solvents, the labeled tylopeptin B analogues preserve the helical propensity of the parent peptide, with a preference for theα‐helix or the 310‐helix type depending upon the nature of the solvent. In aqueous environment, the spin‐labeled analogues present a higher content of helical conformation as a consequence of the strong helix promoter effect of the conformationally constrained TOAC residue. We observed a progressive increase of the quenching effect of the nitroxyl radical on the fluorescence of theN‐terminal tryptophan as TOAC replaces the Aib residue at positions 13, 8, and 4, respectively. A membrane permeabilization assay performed on two selected analogues, TOAC8‐ and TOAC13‐tylopeptin B, showed that the labeled peptides exhibit membrane‐modifying properties comparable with those of the natural peptaibiotic. We conclude that our TOAC paramagnetic analogues of tylopeptin B are good models for a detailed ESR investigation of the mechanism of membrane permeabilization induced by medium‐length peptaibiotics. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
The structure and assembly model of the third transmembrane domain of Slc11a1 in SDS micelles revealed by NMR study of the Leu‐substituted peptide
Authors: Xiao Shuyan , Yang Lei , Li Fei
Published: November 2011

Slc11a1 is an integral membrane protein with 12 putative transmembrane domains (TMDs) and functions as a pH‐coupled divalent metal cation transporter. The conservation of three negatively charged residues in the TMD3 of Slc11 protein family implies the important role of this domain in the function of the proteins. However, aggregation of the transmembrane peptide in micelles prevents structural study of the peptide in these membrane‐mimetic environments by NMR spectroscopy. Here, we characterized the structure, position, and assembly model of Slc11a1‐TMD3 (Lys128‐Ile151) in SDS micelles by the NMR study of its Leu‐substituted peptide. It was found that the two‐site substitutions of Ala for Leu residues at positions 136 and 140 of TMD3 disrupt the aggregation without altering the secondary structure of the peptide. The Leu‐substituted peptide folds as an α‐helix spanning from Leu133 to Gly144 and embedded in the micelles. A Leu zipper is suggested to account for the self‐assembly of the wild‐type peptide in SDS micelles. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.
Optimal sample sizes for phase II clinical trials and pilot studies
Authors: Stallard Nigel
Published: November 2011

Methodology for sample size calculation for phase III clinical trials is well established and widely used. In contrast, for earlier phase clinical trials or pilot studies, although there is an acceptance that the methods used for phase III trials are not appropriate, there is little consensus over methods that should be used. This paper explores this problem from a Bayesian decision‐theoretic perspective. The aim is to obtain sample sizes that would be appropriate for studies funded by a large funder such as a public sector body or major pharmaceutical company. The sample sizes obtained are optimal in that they minimise the average number of patients required per successfully identified effective therapy or equivalently maximise the number of effective therapies successfully identified over a long period.

It is indicated that the number of patients included in a phase II clinical trial should be approximately 0.03 times that planned to be included in the phase III study. This is similar to that proposed by other researchers in this area, though rather smaller than actually used for many phase II trials. Copyright © 2011 John Wiley & Sons, Ltd.
Dedifferentiation-Reprogrammed Mesenchymal Stem Cells with Improved Therapeutic Potential
Authors: Liu Yang , Jiang Xiaohua , Zhang Xiaohu , Chen Rui , Sun Tingting , Fok Kin Lam , Dong Jianda , Tsang Lai Ling , Yi Shaoqiong , Ruan Yechun , Guo Jinghui , Yu Mei Kuen , Tian Yuemin , Chung Yiu Wa , Yang Mo , Xu Wenming , Chung Chin Man , Li Tingyu , Chan Hsiao Chang
Published: November 2011

Stem cell transplantation has been shown to improve functional outcome in degenerative and ischemic disorders. However, low in vivo survival and differentiation potential of the transplanted cells limits their overall effectiveness and thus clinical usage. Here we show that, after in vitro induction of neuronal differentiation and dedifferentiation, on withdrawal of extrinsic factors, mesenchymal stem cells (MSCs) derived from bone marrow, which have already committed to neuronal lineage, revert to a primitive cell population (dedifferentiated MSCs) retaining stem cell characteristics but exhibiting a reprogrammed phenotype distinct from their original counterparts. Of therapeutic interest, the dedifferentiated MSCs exhibited enhanced cell survival and higher efficacy in neuronal differentiation compared to unmanipulated MSCs both in vitro and in vivo, with significantly improved cognition function in a neonatal hypoxic–ischemic brain damage rat model. Increased expression of bcl-2 family proteins and microRNA-34a appears to be the important mechanism giving rise to this previously undefined stem cell population that may provide a novel treatment strategy with improved therapeutic efficacy.
Behavioral dimensions of climate change: drivers, responses, barriers, and interventions
Authors: Gifford Robert , Kormos Christine , McIntyre Amanda
Published: November 2011

This overview describes the anthropogenic drivers of global climate change, reviews the behavioral and psychological responses to its impacts (including barriers to behavior change), considers behavior‐focused intervention strategies, and suggests future directions for research. In doing so, it demonstrates why and how behavioral science is crucial for confronting the complex challenges posed by global climate change. The human dimensions of climate change are discussed, followed by descriptions of key theoretical models for explaining and predicting climate‐relevant behavior, issues and distinctions in studying human behavior in response to global climate change, an account of psychological (as opposed to structural) adaptation and its behavioral sequelae, the many psychological barriers to behavior change in this context, and behavior‐focused intervention strategies. The overview concludes with suggestions for researchers interested in advancing knowledge about behavior change and psychological responses to climate change. When knowledge about human behavior, cognitions, and psychological adaptation is integrated with that produced by researchers in related social and natural science disciplines, the result will facilitate solutions to this massive shared challenge.WIREs Clim Change2011, 2:801–827. doi: 10.1002/wcc.143

This article is categorized under:

Perceptions, Behavior, and Communication of Climate Change > Behavior Change and Responses
Modeling and performance evaluation of Advanced Diffusion with Classified Data in vehicular sensor networks
Authors: Haddadou Nadia , Rachedi Abderrezak , Ghamri‐Doudane Yacine
Published: November 2011

In this paper, we propose a newly distributed protocol called Advanced Diffusion of Classified Data (ADCD) to manage information harvesting and distribution in vehicular sensor networks. ADCD aims at reducing the generated overhead, avoiding network congestions as well as long latency to deliver the harvested information. The concept of ADCD is based on the characterization of sensed information (i.e., based on its importance, location, and time of collection) and the diffusion of this information accordingly. Furthermore, ADCD uses an adaptive broadcasting strategy to avoid overwhelming users with messages in which they have no interest. Also, we propose in this paper a new probabilistic model for ADCD based on Markov chain. This one aims to optimally tune the parameters of ADCD, such as the optimal number of broadcaster nodes. The analytical and simulation results based on different metrics, such as the overhead, the delivery ratio, the probability of a complete transmission, and the minimal number of hops, are presented. These results illustrate that ADCD allows mitigating the information redundancy and its delivery with an adequate latency while making the reception of interesting data for the drivers (related to their location) more adapted. Moreover, the ADCD protocol reduces the overhead by 90% compared with the classical broadcast and an adapted version of MobEyes. The ADCD overhead is kept stable whatever the vehicular density. Copyright © 2011 John Wiley & Sons, Ltd.
Physics for infants: characterizing the origins of knowledge about objects, substances, and number
Authors: Hespos Susan J. , vanMarle Kristy
Published: November 2011

Adults possess a great deal of knowledge about how objects behave and interact in our every day environment, yet several puzzles remain unsolved regarding how we manage this ubiquitous skill. The notion of intuitive physics has been a central focus of research on cognitive development in infancy. This article focuses on the origins of knowledge about objects, substances, and number concepts in infancy. The article reviews common themes of solidity, continuity, cohesion, and property changes as they have been studied with regard to infants' knowledge about objects and more recently with regard to infants' knowledge about substances. In addition, we review how object and substance knowledge interfaces with number knowledge systems. The evidence supports the view that certain core principles about these domains are present as early as we can test for them and the nature of the underlying representation is best characterized as primitive initial concepts that are elaborated and refined through learning and experience. WIREs Cogn Sci 2012, 3:19–27. doi: 10.1002/wcs.157

This article is categorized under:

Psychology > Development and Aging
Validations and improvements of airfoil trailing‐edge noise prediction models using detailed experimental data
Authors: Kamruzzaman M. , Lutz Th. , Würz W. , Shen W. Z. , Zhu W. J. , Hansen M. O. L. , Bertagnolio F. , Madsen H. Aa.
Published: November 2011

This paper describes an extensive assessment and a step by step validation of different turbulent boundary‐layer trailing‐edge noise prediction schemes developed within the European Union funded wind energy project UpWind. To validate prediction models, measurements of turbulent boundary‐layer properties such as two‐point turbulent velocity correlations, the spectra of the associated wall pressure fluctuations and the emitted trailing‐edge far‐field noise were performed in the laminar wind tunnel of the Institute of Aerodynamics and Gas Dynamics, University of Stuttgart. The measurements were carried out for a NACA 643‐418 airfoil, at Re  =  2.5 ×106, angle of attack of −6° to 6°. Numerical results of different prediction schemes are extensively validated and discussed elaborately. The investigations on the TNO‐Blake noise prediction model show that the numerical wall pressure fluctuation and far‐field radiated noise models capture well the measured peak amplitude level as well as the peak position if the turbulence noise source parameters are estimated properly including turbulence anisotropy effects. Large eddy simulation based computational aeroacoustic computations show good agreements with measurements in the frequency region higher than 1 kHz, whereas they over‐predict the sound pressure level in the low‐frequency region. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of parental number and duration of the breeding period on the effective population size and genetic diversity of a captive population of the endangered Tokyo bitterling Tanakia tanago (Teleostei: Cyprinidae)
Authors: Kubota Hitoshi , Watanabe Katsutoshi
Published: November 2011

The maintenance of genetic diversity is one of the chief concerns in the captive breeding of endangered species. Using microsatellite and mtDNA markers, we examined the effects of two key variables (parental number and duration of breeding period) on effective population size (Ne) and genetic diversity of offspring in an experimental breeding program for the endangered Tokyo bitterling, Tanakia tanago. Average heterozygosity and number of alleles of offspring estimated from microsatellite data increased with parental number in a breeding aquarium, and exhibited higher values for a long breeding period treatment (9 weeks) compared with a short breeding period (3 weeks). Haplotype diversity in mtDNA of offspring decreased with the reduction in parental number, and this tendency was greater for the short breeding period treatment. Genetic estimates of Ne obtained with two single‐sample estimation methods were consistently higher for the long breeding period treatment with the same number of parental fish. Average Ne/N ratios were ranged from 0.5 to 1.4, and were high especially in the long breeding period with small and medium parental number treatments. Our results suggest that the spawning intervals of females and alternative mating behaviors of males influence the effective size and genetic diversity of offspring in bitterling. To maintain the genetic diversity of captive T. tanago, we recommend that captive breeding programs should be conducted for a sufficiently long period with an optimal level of parental density, as well as using an adequate number of parents. Zoo Biol 31:656‐668, 2012. © 2011 Wiley Periodicals, Inc.
Delivering a Pharmacogenetic Service: Is There a Role for Genetic Counselors?
Authors: Callard Alice , Newman William , Payne Katherine
Published: November 2011

Pharmacogenetics, the use of genetic information to direct safer and or more effective prescription of medication, is a relatively new clinical concept. Currently, there is no consensus regarding which healthcare professionals should deliver pharmacogenetic services. This study explored the opinions of genetic counselors about their potential role in delivering pharmacogenetic services. Semi‐structured face‐to‐face interviews were conducted with 14 genetic counselors. Four vignettes describing pharmacogenetic testing scenarios were used to elicit views on specific clinical applications. Data were analysed using the constant comparative method. Opinions varied, but the majority of interviewees suggested that genetic counselors could have a role. However, participants suggested that additional training would be needed due to counselors’ limited knowledge of pharmacogenetics. Employing genetic counselors in a specialist role within a multidisciplinary clinic was suggested as a model of service delivery. Service models developed for pharmacogenetic testing may need to be adapted according to the issues presented by each type of test.
Presenilin enhancer‐2 gene: Identification of a novel promoter mutation in a patient with early‐onset familial Alzheimer's disease
Authors: Andreoli Virginia , Trecroci Francesca , La Russa Antonella , Cittadella Rita , Liguori Maria , Spadafora Patrizia , Caracciolo Manuela , Di Palma Gemma , Colica Carmela , Gambardella Antonio , Quattrone Aldo
Published: November 2011

γ‐Secretase proteins complex cleaves the amyloid precursor protein (APP) to generate amyloid‐β (Aβ) peptides. Considerable evidence suggests that alterations in genes encoding these proteins exert their influence on the pathogenesis of familial Alzheimer's disease (FAD). Presenilin enhancer‐2 gene (PEN‐2) is a necessary component of the γ‐Secretase complex. Recently, it has been shown that PEN‐2 mutations could be involved in Alzheimer's disease (AD). We performed a mutational screening of all PEN‐2 coding and promoter regions in a FAD cohort derived from Southern Italy. Four hundred and fifty‐two subjects (FAD: 97; Controls: 355) were recruited for this study. We identified for the first time in a key region necessary for the promoter activity a novel 3 bp deletion in a subject with early‐FAD. Our genetic data demonstrate that the mutant allele may influence the transcriptional activity of the PEN‐2 gene. Although the effective role of the PEN‐2 promoter deletion in AD is not entirely clear, these findings might lead to more studies on its functional and genetic role.
Is Alzheimer's disease amyloidosis the result of a repair mechanism gone astray?
Authors: Kokjohn Tyler A. , Maarouf Chera L. , Roher Alex E.
Published: November 2011

Here, we synthesize several lines of evidence supporting the hypothesis that at least one function of amyloid‐β is to serve as a part of the acute response to brain hemodynamic disturbances intended to seal vascular leakage. Given the resilient and adhesive physicochemical properties of amyloid, an abluminal hemostatic repair system might be highly advantageous, if deployed on a limited and short‐term basis, in young individuals. However, in the aged, inevitable cardiovascular dysfunction combined with brain microvascular lesions may yield global chronic hypoperfusion that may lead to continuous amyloid deposition and consequential negative effects on neuronal viability. A large body of experimental evidence supports the hypothesis of an amyloid‐β rescue function gone astray. Preventing or inducing the removal of amyloid in Alzheimer's disease (AD) has been simultaneously successful and disappointing. Amyloid deposits clearly play major roles in AD, but they may not represent the preeminent factor in dementia pathogenesis. Successful application of AD preventative approaches may hinge on an accurate and comprehensive view of comorbidities, including cardiovascular disease, diabetes, and head trauma.