bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of inorganic fillers on the flame‐retardant and mechanical properties of rigid polyurethane foams
Authors: Cheng Jia‐Ji , Shi Bo‐Bo , Zhou Fu‐Bao , Chen Xiao‐Yu
Published: December 2013

Rigid polyurethane foam (RPUF) composites filled with expandable graphite (EG), hollow glass microspheres (HGM), and glass fibers (GF) have been synthesized and characterized by limiting oxygen index, radiation ignition, compressing and torsion testing, and scanning electron microscopy. The results indicate HGM and GF benefit to the mechanical properties, while EG is good for flame retardancy. Proper ingredient of additive can lead to good flame retardancy and mechanical properties of the RPUF. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40253.
Switchable Substrates for Analyzing and Engineering Cellular Functions
Authors: Nakanishi Jun
Published: December 2013

Cellular activity is highly dependent on the extracellular environment, which is composed of surrounding cells and extracellular matrices. This focus review summarizes recent advances in chemically and physically engineered switchable substrates designed to control such cellular microenvironments by application of an external stimulus. Special attention is given to their molecular design, switching strategies, and representative examples for bioanalytical and biomedical applications.
Simultaneous determination of some dihydroxybenzenesulphonic acid derivatives and their degradation product and main impurity (hydroquinone) by ion‐pair liquid chromatography
Authors: Tolba M. M.
Published: December 2013

A simple and sensitive high‐performance liquid chromatography method was developed and validated for the determination of calcium dobesilate (DOB) or ethamsylate (ETM) in the presence of their degradation product, hydroquinone (HQ). The analyses were carried out on Promosil C18 column (4.6 mm × 250 mm, 5 µm particle size) using an ion‐pair mobile phase consisting of methanol–1.5 mm tetra‐butyl ammonium bromide in 0.06 m phosphate buffer (25 : 75, v/v) at pH 6.0 with fluorescence detection at 286/333 nm. Pindolol was used as an internal standard. The proposed method was found to be rectilinear over the concentration ranges of 0.05–0.5 µg/mL for DOB, 0.1–0.8 µg/mL for ETM and 0.005–0.1 µg/mL for HQ. The method was applied for the determination of the studied drugs in different dosage forms and biological fluids. The results of the proposed method were statistically compared with those obtained by the comparison methods revealing no significance differences in the performance of the methods regarding accuracy and precision. Moreover, applying a time‐programmed fluorescence technique was valuable for the detection of trace amounts of HQ as an impurity and allowed purity testing of ETM or DOB within the BP pharmacopeial limit (0.1%). Copyright © 2013 John Wiley & Sons, Ltd.
Fallenbewegungen fleischfressender Pflanzen
Authors: Poppinga Simon , Metzger Amélie , Speck Olga , Masselter Tom , Speck Thomas
Published: December 2013

Langsame Pflanzenbewegungen laufen vornehmlich mit hydraulischen “Motoren” ab, d. h. die auftretenden Verformungen werden durch eine Verschiebung von Wasser zwischen Zellen und Geweben hervorgerufen. Vor allem bei großen und schnellen Strukturen (zum Beispiel den Schnappfallen der carnivoren Venusfliegenfalle) treten elastische Instabilitäten auf und beschleunigen den Bewegungsvorgang deutlich. Die bei den vorgestellten carnivoren Pflanzen zur Anwendung kommenden mechanischen “Tricks” lassen sich in abstrahierter Form mittels einfacher physikalischer Handmodelle veranschaulichen und tragen zum Verständnis der involvierten Prozesse bei.
Dinosaurier aus Nordostdeutschland
Authors: Stumpf Sebastian , Meng Stefan
Published: December 2013

Die ehemalige Tongrube Grimmen (Nordostdeutschland) ist ein Übertageaufschluss glazial verschleppter, unterjurassischer flachmariner Sedimente. Neben typischen marinen Organismen wurden die Reste des basalen thyreophoren Dinosauriers Emausaurus ernsti gefunden. E. ernsti war ein vergleichsweise kleiner Dinosaurier, der eine Körperpanzerung, bestehend aus kleinen, isolierten Hautpanzerplatten, besaß. Kürzlich konnten die Reste eines zweiten Dinosauriers, welcher zur Gruppe der Sauropoden gehört, nachgewiesen werden. Dieser stellt den zweiten Fund eines unterjurassischen basalen Sauropoden innerhalb Deutschlands dar. Der Sauropode wurde vermutlich nach seinem Tod über einen Fluss vom Festland ins Meer eingespült. Die Fossilüberlieferung von E. ernsti, dessen Knochen in einer Konkretion gefunden wurden, wird hingegen als Speiballen eines großen Meeresreptils interpretiert.
An improved highly sensitive method to determine low oxyresveratrol concentrations in rat plasma and its pharmacokinetic application
Authors: Tian Fangzhen , Wei Hongtu , Jia Tanghong , Tian Hua
Published: December 2013

Existing methods to determine oxyresveratrol, a trans‐polyphenolic stilbene, lack selectivity, require large plasma sample volumes or have time‐consuming sample preparation and chromatographic isolation. Here an improved highly sensitive liquid chromatography–tandem mass spectrometry method was developed to determine low oxyresveratrol concentrations in rat plasma. The plasma samples were prepared by liquid–liquid extraction with acetoacetate. The analytes were separated on Venusil hydrophilic interaction chromatography (HILIC) column (2.1 × 50 mm, 5.0 µm) guarded by a HILIC column (4 × 3.0 mm, 5.0 µm). The mobile phase consisted of acetonitrile–water (containing 1 mmol/L ammonium formate) at gradient elution mode with a flow rate of 0.3 mL/min. Resveratrol was used as the internal standard. An electrospray ionization source was applied and operated in the negative multiple reaction monitoring (MRM) mode. Oxyresveratrol and resveratrol were detected on MRM by the transitions from the precursor to the product ion (m/z 243.1 → 175.1 and 227.1 → 143.0). The total running time was 5 min and the retention times of oxyresveratrol and resveratrol were 1.97 and 1.82 min. Chromatograms showed no endogenous interfering peaks with blank samples. The linear calibration curve was obtained over the concentration range of 1–500 ng/mL. The injection volume was 10 μL and the limit of quantification was 1 ng/mL. The extraction recovery varied from 78.2 to 84.3% for low, medium and high quality control samples. At the same time, the intra‐ and inter‐day relative standard deviations were <6.78 and <10.02%, respectively, while the corresponding intra‐ and inter‐day accuracy relative error values fell in the range of 3.75–6.67%. The HPLC‐MS/MS method was successfully applied to a pharmacokinetics study, in which the experimental rats received a single dose of oxyresveratrol (10 mg/kg, intragastric administration). The pharmacokinetic results are presented. Copyright © 2013 John Wiley & Sons, Ltd.
European doctoral forum at the 14th international society of scientometrics and informetrics conference
Authors: Schlögl Christian
Published: December 2013

Editor's Summary

The International Society for Scientometrics and Informetrics (ISSI) conference welcomed the European Doctoral Forum in Vienna in July 2013. ASIS&T SIG/MET and ASIS&T's European Student Chapter joined the University of Vienna's Center for Doctoral Studies in organizing the forum, which provided an opportunity for doctoral students to discuss their research and receive feedback from renowned scientometricians. Nine students representing five countries and a variety of disciplines presented their work. Topics included altmetrics, electronic visualization and regional differences in research over time. The scholarly exchanges were capped by lunch and traditional Viennese coffees.
Information architects: What we do and how we learn
Authors: Haller Thom
Published: December 2013

Editor's Summary

Defining the field of information architecture is as challenging as ever, but this ASIS&T Bulletin special section includes several successful efforts from different perspectives. The lead article recasts the widely shared practice of organizing information resources as a discipline itself, building a commonly applicable model with widely understandable, generic terminology for broad implementation across diverse fields. The gap between formal education and real‐life learning about information architecture is the focus of another article that presents a survey and audience feedback from World IA Day. Other contributions target the practical aspects of shepherding information content through organizational platform migrations, best accomplished by a multidisciplinary team with a common understanding of the information domain. Reflections upon 15 years teaching the subject of information architecture provide an opportunity to review lessons learned and consider how they apply beyond the field.
What sticks: Reflections from 15 years as an IA instructor
Authors: Haller Thom
Published: December 2013

Editor's Summary

In his 15 years of teaching information architecture classes, Thom Haller's aim for students was to identify their goals and help them work toward them. His 10‐week courses focused on useful knowledge about how humans think and use information and how good information architecture can facilitate the process. The courses covered visual thinking, user actions, interconnections between information items and navigating mental models. From the theories and techniques introduced in the course, the most important points would continually surface when the class considered the question, “What sticks?” Weekly and at the end of a course, the students reflected on lessons with lasting value about the field, user experience and the practice of information architecture. In recent discussions with Haller, former students reported on enduring principles that stuck, resonating through their daily work. They agreed that the core tenet of information architecture — that making things simple and understandable creates the best user experience — is equally true in other domains. The concept is graphically represented by a triangle of connected fingers, symbolizing audience, goals and success metrics around a communication product.
Migrations: Not just for developers any more
Authors: Land Paula
Published: December 2013

Editor's Summary

Migrating content between sites is a complex process requiring the carefully timed and coordinated work of a multidisciplinary team. Not just the work of IT specialists, site migration is best handled by developers, a project manager, business analyst, information architect and content strategist working together. Planning starts with a current site inventory and audit, when the content strategist assesses content, types, metadata and functions served. The information architect focuses on site structure, taxonomy, navigation and usability. The taxonomy should be implemented with an eye to serving organization, tagging and templates for author submissions and presentation. The migration process presents an opportunity to update and enhance the site. Best results depend on good decisions made early in the process by information specialists working with others for a site that serves users as well as the sponsor's goals.
Data curators at work: Focus on projects and experiences
Authors: Kouper Inna , Akers Katherine , Lavin Matthew
Published: December 2013

Editor's Summary

Three postdoctoral fellows in a program sponsored by the Council on Library and Information Resources/Digital Library Foundation are exploring and contributing to the field of digital curation through very different perspectives. With a neuroscience background, Katherine Akers is encouraging scientists to preserve and share research datasets and analyzing the use of library resources. For Inna Kouper, building cyberstructure and facilitating and promoting user engagement are primary. Matthew Lavin is working to make digital tools and approaches serve the needs of humanists, focusing on digitally conveying the physical features and histories of books. With different definitions of data and a variety of research goals, the scholars apply hybrid professional approaches to digital curation, stimulating expanded information, intellectual cross fertilization and a broader view of data, research and knowledge.
Variation of the Chemical Composition and Antimicrobial Activity of the Essential Oils of Natural Populations of Tunisian Daucus carota L. (Apiaceae)
Authors: Rokbeni Nesrine , M'rabet Yassine , Dziri Salma , Chaabane Hedia , Jemli Marwa , Fernandez Xavier , Boulila Abdennacer
Published: December 2013

The essential oils of Daucus carota L. (Apiaceae) seeds sampled from ten wild populations spread over northern Tunisia were characterized by GC‐FID and GC/MS analyses. In total, 36 compounds were identified in the D. carota seed essential oils, with a predominance of sesquiterpene hydrocarbons in most samples (22.63–89.93% of the total oil composition). The main volatile compounds identified were β‐bisabolene (mean content of 39.33%), sabinene (8.53%), geranyl acetate (7.12%), and elemicin (6.26%). The volatile composition varied significantly across the populations, even for oils of populations harvested in similar areas. The chemometric principal component analysis and the hierarchical clustering identified four groups, each corresponding to a composition‐specific chemotype. The in vitro antimicrobial activity of the isolated essential oils was preliminarily evaluated, using the disk‐diffusion method, against one Gram‐positive (Staphylococcus aureus) and two Gram‐negative bacteria (Escherichia coli and Salmonella typhimurium), as well as against a pathogenic yeast (Candida albicans). All tested essential oils exhibited interesting antibacterial and antifungal activities against the assayed microorganisms.
Enzymatic Modification of Palmarosa Essential Oil: Chemical Analysis and Olfactory Evaluation of Acylated Products
Authors: Ramilijaona Jade , Raynaud Elsa , Bouhlel Charfeddine , Sarrazin Elise , Fernandez Xavier , Antoniotti Sylvain
Published: December 2013

We have developed an enzymatic protocol to modify the composition of palmarosa essential oil by acylation of its alcohol components by three different acyl donors at various rates. The resulting modified products were characterized by qualitative and quantitative analyses by gas chromatography, and their olfactory properties were evaluated by professional perfumers. We showed that our protocol resulted in two types of modifications of the olfactory properties. The first and most obvious effect observed was the decrease of the alcohol content, with the concomitant increase of the corresponding esters, along with their fruity notes (pear, most notably). The second and less obvious effect was the expression of notes from minor components ((E)‐β‐ocimene, linalool, β‐caryophyllene, and farnesene), originally masked by the sweet‐floral‐rose odor of geraniol, present in 70% in the palmarosa essential oil used, and emergence of citrus, green, spicy and clove characters in the modified products. This methodology might be considered in the future as a sustainable route to new natural ingredients for the perfumer.
5α‐Androst‐16‐en‐3α‐ol β‐D‐Glucuronide, Precursor of 5α‐Androst‐16‐en‐3α‐ol in Human Sweat
Authors: Starkenmann Christian , Mayenzet Fabienne , Brauchli Robert , Troccaz Myriam
Published: December 2013

5α‐Androst‐16‐en‐3α‐ol (α‐androstenol) is an important contributor to human axilla sweat odor. It is assumed that α‐andostenol is excreted from the apocrine glands via a H2O‐soluble conjugate, and this precursor was formally characterized in this study for the first time in human sweat. The possible H2O‐soluble precursors, sulfate and glucuronide derivatives, were synthesized as analytical standards, i.e., α‐androstenol, β‐androstenol sulfates, 5α‐androsta‐5,16‐dien‐3β‐ol (β‐androstadienol) sulfate, α‐androstenol β‐glucuronide, α‐androstenol α‐glucuronide, β‐androstadienol β‐glucuronide, and α‐androstenol β‐glucuronide furanose. The occurrence of α‐androstenol β‐glucuronide was established by ultra performance liquid chromatography (UPLC)/MS (heated electrospray ionization (HESI)) in negative‐ion mode in pooled human sweat, containing eccrine and apocrine secretions and collected from 25 female and 24 male underarms. Its concentration was of 79 ng/ml in female secretions and 241 ng/ml in male secretions. The release of α‐androstenol was observed after incubation of the sterile human sweat or α‐androstenol β‐glucuronide with a commercial glucuronidase enzyme, the urine‐isolated bacteria Streptococcus agalactiae, and the skin bacteria Staphylococcus warneri DSM 20316, Staphylococcus haemolyticus DSM 20263, and Propionibacterium acnes ATCC 6919, reported to have β‐glucuronidase activities. We demonstrated that if α‐ and β‐androstenols and androstadienol sulfates were present in human sweat, their concentrations would be too low to be considered as potential precursors of malodors; therefore, the H2O‐soluble precursor of α‐androstenol in apocrine secretion should be a β‐glucuronide.
Sebaceous Lipid Profiling of Bat Integumentary Tissues: Quantitative Analysis of Free Fatty Acids, Monoacylglycerides, Squalene, and Sterols
Authors: Pannkuk Evan L. , Gilmore David F. , Fuller Nathan W. , Savary Brett J. , Risch Thomas S.
Published: December 2013

White‐nose syndrome (WNS) is a fungal disease caused by Pseudogymnoascus destructans and is devastating North American bat populations. Sebaceous lipids secreted from host integumentary tissues are implicated in the initial attachment and recognition of host tissues by pathogenic fungi. We are interested in determining if ratios of lipid classes in sebum can be used as biomarkers to diagnose severity of fungal infection in bats. To first establish lipid compositions in bats, we isolated secreted and integral lipid fractions from the hair and wing tissues of three species: big brown bats (Eptesicus fuscus), Eastern red bats (Lasiurus borealis), and evening bats (Nycticeius humeralis). Sterols, FFAs, MAGs, and squalene were derivatized as trimethylsilyl esters, separated by gas chromatography, and identified by mass spectrometry. Ratios of sterol to squalene in different tissues were determined, and cholesterol as a disease biomarker was assessed. Free sterol was the dominant lipid class of bat integument. Squalene/sterol ratio is highest in wing sebum. Secreted wing lipid contained higher proportions of saturated FFAs and MAGs than integral wing or secreted hair lipid. These compounds are targets for investigating responses of P. destructans to specific host lipid compounds and as biomarkers to diagnose WNS.
A Differential Fluorescent Receptor for Nucleic Acid Analysis
Authors: Bengtson Hillary N. , Kolpashchikov Dmitry M.
Published: December 2013

Differential receptors use an array of sensors to recognize analytes. Each sensor in the array can recognize not one, but several analytes with different rates, so a single analyte triggers a response of several sensors in the array. The receptor thus produces a pattern of signals that is unique for each analyte, thereby enabling identification of a specific analyte by producing a “fingerprint” pattern. We applied this approach for the analysis of DNA sequences of Mycobacterium tuberculosis strains that differ by single nucleotide substitutions in the 81‐bp hot‐spot region that imparts rifampin resistance. The technology takes advantage of the new multicomponent, selfassembling sensor, which produces a fluorescent signal in the presence of specific DNA sequences. A differential fluorescent receptor (DFR) contained an array of three such sensors and differentiated at least eight DNA sequences. The approach requires only one molecular‐beacon‐like fluorescent reporter, which can be used by all three sensors. The DFR developed in this study represents a cost‐efficient alternative to molecular diagnostic technologies that use fluorescent hybridization probes.
Magnetic navigation facilitates percutaneous coronary intervention for complex lesions
Authors: Sandhu Gurpreet S. , Sanon Saurabh , Holmes David R. , Gulati Rajiv , Brilakis Emmanouil S. , Lennon Ryan J. , Rihal Charanjit S.
Published: December 2013

Background

We sought to determine the utility of a magnetic navigation system (MNS) in treating a variety of coronary artery lesions including those that could not be revascularized with standard percutaneous coronary intervention (PCI). MNS may add value in the treatment of tortuous arteries and bifurcation lesions; however its widespread adoption has lagged because of cost and a lack of clear advantage over conventional PCI. We performed a retrospective analysis to determine whether MNS improved procedural success for highly complex lesions.

Methods and Results

One hundred and forty‐eight patients underwent treatment with MNS at Mayo Clinic, Rochester. Clinical data, angiographic and procedural characteristics, lesion crossing success and outcomes were reviewed. Overall 133 patients underwent successful revascularization with 87% (143) of 164 lesions crossed using MNS alone. Another six lesions required a combination of MNS and conventional devices resulting in overall success of 91% (149/164). Eighteen complex lesions had previously failed PCI and 12 (67%) were successfully treated with MNS. Success after failed PCI was higher (88%) when a frequent user operated MNS, but occasional users also noted incremental success (30%). Twenty‐five chronic total occlusions were included amongst these 164 lesions, with observed antegrade MNS lesion crossing rates of 78% for regular and 14% for occasional users.

Conclusions

MNS is a useful adjunct to performance of PCI. This specialized technology has a clear learning curve and can facilitate treatment of highly complex lesions. © 2013 Wiley Periodicals, Inc.
Clinical outcomes in real‐world patients with small vessel disease treated with XIENCE V® everolimus‐eluting stents: One year results from the XIENCE V® USA condition of approval post‐market study
Authors: Hermiller James B. , Rutledge David R. , Mao Vivian W. , Zhao Weiying , Wang Jin , Gruberg Luis , Lombardi William , Sharma Samin K. , Krucoff Mitchell W.
Published: December 2013

Objectives

The purpose of this study was to evaluate the 1‐year clinical outcomes of more complex XIENCE V USA real‐world patients with small versus nonsmall vessel lesions.

Background

Patients with small vessel lesions undergoing coronary stent placement are at higher risk of major adverse cardiac events. Improved safety and efficacy of XIENCE V everolimus eluting stents (EES) have been previously demonstrated in selected low‐risk small vessel populations in randomized clinical trials.

Methods

The XIENCE V USA study was a condition of approval, single‐arm study in unselected real‐world patients. Baseline and 1‐year clinical outcomes were compared between XIENCE V USA patients who received a single 2.5 mm stent (small vessel group, N = 838) and patients implanted with a single >2.5 mm stent (non‐small vessel group, N = 2,015). Mean reference vessel diameter was 2.55 ± 0.36 and 3.25 ± 0.46 mm in the small and non‐small vessel groups, respectively (P < 0.001).

Results

Small vessel group had more females, presented with a higher rate of diabetes, and had more complex lesion characteristics. The definite or probable ST rates analyzed using Kaplan–Meier method were low and not significantly different between the groups at 0.37 and 0.40% for the small and nonsmall vessel group (P = 0.88), respectively. The composite rate of cardiac death or MI was comparable at 4.5% for the small and 5.1% for the non‐small vessel 1 groups (P = 0.57). The 1‐year target lesion revascularization rate was also comparable in the small vessel group (3.8% vs. 3.0%, P = 0.35).

Conclusions

Despite gender difference, higher prevalence of diabetes and more complex lesions in the small vessel groups, the 1‐year clinical outcomes were similar in both small and nonsmall vessel groups. These results demonstrate the therapeutic benefit of XIENCE V EES in a real‐world all inclusive patient population with small vessel disease. © 2013 Wiley Periodicals, Inc.
Effect of the Nature and Location of Copper Species on the Catalytic Nitric Oxide Selective Catalytic Reduction Performance of the Copper/SSZ‐13 Zeolite
Authors: Guo Qiang , Fan Fengtao , Ligthart D. A. J. Michel , Li Guanna , Feng Zhaochi , Hensen Emiel J. M. , Li Can
Published: December 2013

The nature and location of copper in Cu/SSZ‐13 zeolites synthesized by using a one‐pot hydrothermal approach with Cu–tetraethylenepentamine as a template and by the ion exchange of SSZ‐13 were investigated by applying H2‐temperature‐programmed reduction, FTIR, EPR, and in situ Raman spectroscopic techniques. The one‐pot synthesized Cu/SSZ‐13 zeolite contains predominantly isolated copper ions in the large cages, whereas copper species in the ion‐exchanged Cu/SSZ‐13 zeolite occupy sites in the large cages of the chabazite (CHA) structure and the six‐membered rings of the CHA structure. If the one‐pot synthesized Cu/SSZ‐13 zeolite is exchanged with the NH4NO3 solution in addition to the removal of a part of copper ions, the remaining copper ions in the CHA structure relocated from the large cages to the six‐membered rings. Isolated copper dominated in all Cu/SSZ‐13 zeolites. The in situ Raman spectra demonstrated that CuOCu dimers form at higher copper content. The bis‐μ‐oxo dicopper(III) complex is observed only in the ion‐exchanged sample upon dehydration. The higher NO selective catalytic reduction activity of the one‐pot synthesized sample in a wide temperature range appears to be due to the predominance of isolated Cu2+ sites in the large cages, and their higher reactivity is possibly owing to the lower stability of Cu2+ at these sites.
On the Physicochemical Properties of Pyridohelicenes
Authors: Vacek Chocholoušová Jana , Vacek Jaroslav , Andronova Angelina , Míšek Jiří , Songis Olivier , Šámal Michal , Stará Irena G. , Meyer Michel , Bourdillon Mélanie , Pospíšil Lubomír , Starý Ivo
Published: December 2013

A comprehensive study on the physicochemical properties of a series of mono‐ and diaza[5]helicenes as well as mono‐ and diaza[6]helicenes is reported. Through the use of both computational and experimental methods, these helically chiral pyridohelicenes with the nitrogen atom(s) in various positions are characterised according to their inversion barriers, protonation constants and redox potentials. By using DFT calculations, kinetic measurements, UV/Vis titrations, cyclic voltammetry and EPR spectroscopy, a self‐contained picture of their behaviour under conventional treatment by heat, acids and oxidising/reducing agents is provided.
Sequence‐Specific DNA Recognition by Cyclic Pyrrole–Imidazole Cysteine‐Derived Polyamide Dimers
Authors: Yamamoto Makoto , Bando Toshikazu , Morinaga Hironobu , Kawamoto Yusuke , Hashiya Kaori , Sugiyama Hiroshi
Published: December 2013

Pyrrole–imidazole (PI) polyamides bind to the minor groove of the DNA duplex in a sequence‐specific manner and thus have the potential to regulate gene expression. To date, various types of PI polyamides have been designed as sequence‐specific DNA binding ligands. One of these, cysteine cyclic PI polyamides containing two β‐alanine molecules, were designed to recognize a 7 bp DNA sequence with high binding affinity. In this study, an efficient cyclization reaction between a cysteine and a chloroacetyl residue was used for dimerization in the synthesis of a unit that recognizes symmetrical DNA sequences. To evaluate specific DNA binding properties, dimeric PI polyamide binding was measured by using a surface plasmon resonance (SPR) method. Extending this molecular design, we synthesized a large dimeric PI polyamide that can recognize a 14 bp region in duplex DNA.
Tetrapeptidic Molecular Hydrogels: Self‐assembly and Co‐aggregation with Amyloid Fragment Aβ1‐40
Authors: Tena‐Solsona Marta , Miravet Juan F. , Escuder Beatriu
Published: December 2013

A new family of isomeric tetrapeptides containing aromatic and polar amino acid residues that are able to form molecular hydrogels following a smooth change in pH is described. The hydrogels have been studied by spectroscopic and microscopic techniques showing that the peptide primary sequence has an enormous influence on the self‐assembly process. In particular, the formation of extended hydrophobic regions and the appearance of π‐stacking interactions have been revealed as the driving forces for aggregation. Moreover, the interaction of these compounds with amyloid peptidic fragment Aβ1‐40 has been studied and some of them have been shown to act as templates for the aggregation of this peptide into non‐β‐sheet fibrillar structures. These compounds could potentially be used for the capture of toxic, soluble amyloid oligomers.
A New Class of Dendritic Metallogels with Multiple Stimuli‐Responsiveness and as Templates for the In Situ Synthesis of Silver Nanoparticles
Authors: Liu Zhi‐Xiong , Feng Yu , Zhao Zhi‐Yong , Yan Zhi‐Chao , He Yan‐Mei , Luo Xu‐Jun , Liu Chen‐Yang , Fan Qing‐Hua
Published: December 2013

A new class of poly(aryl ether) dendritic ligands containing a pyridine functionality at the focal point and the corresponding AgI complexes through metal–ligand coordination were designed, synthesized, and fully characterized. Compared with the dendritic ligands, the corresponding dendritic complexes exhibited much better gelation ability for various organic solvents at very low critical gelation concentrations. The gel–sol phase transition temperatures and morphologies could be finely tuned by binding silver ion to the ligand. A preliminary study revealed that multiple noncovalent interactions, such as AgI–pyridine coordination, solvophobic interaction, and π–π stacking, synergistically enable the formation of stable metallogels. Interestingly, these metallogels could intelligently respond to multiple external stimuli including temperature, chemicals, and shear stress, leading to gel–sol phase transitions. In addition, these dendritic metallogels were successfully applied as templates for the in situ formation and stabilization of silver nanoparticles without the use of any chemical reducing/stabilizing agents.
Pyrene‐Based Fluorescent Ambidextrous Gelators: Scaffolds for Mechanically Robust SWNT–Gel Nanocomposites
Authors: Mandal Deep , Kar Tanmoy , Das Prasanta Kumar
Published: December 2013

With the rapid progress in the development of supramolecular soft materials, examples of low‐molecular‐weight gelators (LMWGs) with the ability to immobilise both water and organic solvents by the same structural scaffold are very limited. In this paper, we report the development of pyrene‐containing peptide‐based ambidextrous gelators (AGs) with the ability to efficiently gelate both organic and aqueous solvents. The organo‐ and hydrogelation efficiencies of these gelators are in the range 0.7–1.1 % w/v in various organic solvents and 0.5–5 % w/v in water at certain acidic pH values (pH 2.0–4.0). Moreover, for the first time, AGs have been utilised to prepare single‐walled carbon‐nanotube (SWNT)‐included soft nanocomposites in both hydro‐ and organogel matrices. The influence of different non‐covalent interactions such as hydrogen bonding, hydrophobic, π–π and van der Waals interactions in self‐assembled gelation has been studied in detail by circular dichroism, FTIR, variable‐temperature NMR, 2D NOESY and luminescence spectroscopy. Interestingly, the presence of the pyrene moiety in the structure rendered these AGs intrinsically fluorescent, which was quenched upon successful integration of the SWNTs within the gel. The prepared hydro‐ and organogels along with their SWNT‐integrated nanocomposites are thermoreversible in nature. The supramolecular morphologies of the dried gels and SWNT–gel nanocomposites have been studied by transmission electron microscopy, fluorescence microscopy and polarising optical microscopy, which confirmed the presence of three‐dimensional self‐assembled fibrillar networks (SAFINs) as well as the integrated SWNTs. Importantly, rheological studies revealed that the inclusion of SWNTs within the ambidextrous gels improved the mechanical rigidity of the resulting soft nanocomposites up to 3.8‐fold relative to the native gels.
Towards Design Rules for Covalent Nanostructures on Metal Surfaces
Authors: Björk Jonas , Hanke Felix
Published: December 2013

The covalent molecular assembly on metal surfaces is explored, outlining the different types of applicable reactions. Density functional calculations for on‐surface reactions are shown to yield valuable insights into specific reaction mechanisms and trends across the periodic table. Finally, it is shown how design rules could be derived for nanostructures on metal surfaces.
Enhancing the Electrochemical Performance of the LiMn2O4 Hollow Microsphere Cathode with a LiNi0.5Mn1.5O4 Coated Layer
Authors: Liu Wei , Liu Jun , Chen Kunfeng , Ji Shaomin , Wan Yanling , Zhou Yichun , Xue Dongfeng , Hodgson Peter , Li Yuncang
Published: December 2013

Spinel cathode materials consisting of LiMn2O4@LiNi0.5Mn1.5O4 hollow microspheres have been synthesized by a facile solution‐phase coating and subsequent solid‐phase lithiation route in an atmosphere of air. When used as the cathode of lithium‐ion batteries, the double‐shell LiMn2O4@LiNi0.5Mn1.5O4 hollow microspheres thus obtained show a high specific capacity of 120 mA h g−1 at 1 C rate, and excellent rate capability (90 mAhg−1 at 10 C) over the range of 3.5–5 V versus Li/Li+ with a retention of 95 % over 500 cycles.
PPh3⋅HBr‐DMSO Mediated Expedient Synthesis of γ‐Substituted β,γ‐Unsaturated α‐Ketomethylthioesters and α‐Bromo Enals: Application to the Synthesis of 2‐Methylsulfanyl‐3(2 H)‐furanones
Authors: Mal Kanchan , Sharma Abhinandan , Maulik Prakas R. , Das Indrajit
Published: December 2013

An efficient chemoselective general procedure for the synthesis of γ‐substituted β,γ‐unsaturated α‐ketomethylthioesters from α,β‐unsaturated ketones has been achieved through an unprecedented PPh3⋅HBr‐DMSO mediated oxidative bromination and Kornblum oxidation sequence. The newly developed reagent system serves admirably for the synthesis of α‐bromoenals from enals. Furthermore, AuCl3‐catalyzed efficient access to 3(2H)‐furanones from the above intermediates under extremely mild conditions are described.
Strong Intermolecular Exciton Couplings in Solid‐State Circular Dichroism of Aryl Benzyl Sulfoxides
Authors: Padula Daniele , Pietro Sebastiano Di , Capozzi Maria Annunziata M. , Cardellicchio Cosimo , Pescitelli Gennaro
Published: December 2013

A series of 13 enantiopure aryl benzyl sulfoxides (1a, 1b, 1c, 1d, 1e, 1f, 1g, 1h, 1i, 1j, 1k, 1l, 1m) with different substituents on the two aromatic rings has been previously analyzed by means of electronic circular dichroism (CD) spectroscopy. Most of these compounds are crystalline and their X‐ray structure is established. For almost one‐half of the series, CD spectra measured in the solid state were quite different from those in acetonitrile solution. We demonstrate that the difference is due to strong exciton couplings between molecules packed closely together in the crystal. The computational approach consists of time‐dependent density functional theory (TDDFT) calculations run on “dimers” composed of nearest neighbors found in the lattice. Solid‐state CD spectra are well reproduced by the average of all possible pairwise terms. The relation between the crystal space group and conformation, and the appearance of solid‐state CD spectra, is also discussed. Chirality 26:462–470, 2013. © 2013 Wiley Periodicals, Inc.
Adsorptive Pretreatment of Crude Glycerol Prior to Fermentation to 1,3‐Propanediole by Clostridium Diolis
Authors: Wiesen Sebastian , Tippkötter Nils , Muffler Kai , Suck Kirstin , Sohling Ulrich , Ruf Nils , Ulber Roland
Published: December 2013

Bei der Gewinnung von Fettsäuren aus Pflanzenölen, z. B. zur Herstellung von Biopolymeren, oder bei der Biodiesel‐ und Seifenproduktion, fällt Glycerin als Nebenprodukt an. Bei der Biokonversion dieses Rohstoffes zu 1,3‐Propandiol wird der Produktionsorganismus Clostridium diolis durch Verunreinigungen im Rohglycerin gehemmt. Als inhibierende Substanzen konnten freie Fettsäuren identifiziert werden. Mithilfe eines adsorptiven Aufarbeitungsverfahrens ist es gelungen, die Fettsäuren zu entfernen und die Konversionseffizienz zu 1,3‐Propandiol zu erhöhen.
A One‐pot Approach to Ethyl 1,4,5‐Triaryl‐1H‐pyrazole‐3‐carboxylates via an Improved Claisen Condensation‐Knorr Reaction Sequence
Authors: Zhai Jiaojiao , Gu Chunhui , Jiang Jianan , Zhang Shunli , Liao Daohua , Wang Lei , Zhu Dunru , Ji Yafei
Published: December 2013

A one‐pot approach to ethyl 1,4,5‐triaryl‐1H‐pyrazole‐3‐carboxylates has been developed in moderate to high yields. The tert‐BuOLi‐mediated Claisen condensation of 1,2‐diarylethanones and ethyl oxalyl chloride efficiently provided the enolized lithium salts of ethyl 2,4‐dioxo‐3,4‐diarylbutanoates, which in situ reacted with arylhydrazine hydrochlorides via a hydrochloric acid‐promoted Knorr reaction to produce the exquisite triarylpyrazole‐3‐carboxylates. The procedure promises a convenient access to this highly crowded framework for drug discovery.
Resistant Hypertension Optimal Treatment Trial: A Randomized Controlled Trial
Authors:   The ReHOT Investigators
Published: December 2013

The prevalence of resistant hypertension (ReHy) is not well established. Furthermore, diuretics, angiotensin‐converting enzyme inhibitors or angiotensin‐receptor blockers, and calcium channel blockers are largely used as the first 3‐drug combinations for treating ReHy. However, the fourth drug to be added to the triple regimen is still controversial and guided by empirical choices. We sought (1) to determine the prevalence of ReHy in patients with stage II hypertension; (2) to compare the effects of spironolactone vs clonidine, when added to the triple regimen; and (3) to evaluate the role of measuring sympathetic and renin‐angiotensin‐aldosterone activities in predicting blood pressure response to spironolactone or clonidine. The Resistant Hypertension Optimal Treatment (ReHOT) study (ClinicalTrials.gov NCT01643434) is a prospective, multicenter, randomized trial comprising 26 sites in Brazil. In step 1, 2000 patients will be treated according to hypertension guidelines for 12 weeks, to detect the prevalence of ReHy. Medical therapy adherence will be checked by pill count monitoring. In step 2, patients with confirmed ReHy will be randomized to an open label 3‐month treatment with spironolactone (titrating dose, 12.5–50 mg once daily) or clonidine (titrating dose, 0.1–0.3 mg twice daily). The primary endpoint is the effective control of blood pressure after a 12‐week randomized period of treatment. The ReHOT study will disseminate results about the prevalence of ReHy in stage II hypertension and the comparison of spironolactone vs clonidine for blood pressure control in patients with ReHy under 3‐drug standard regimen.
An open‐label, single‐arm, phase 2 trial of the polo‐like kinase inhibitor volasertib (BI 6727) in patients with locally advanced or metastatic urothelial cancer
Authors: Stadler Walter M. , Vaughn David J. , Sonpavde Guru , Vogelzang Nicholas J. , Tagawa Scott T. , Petrylak Daniel P. , Rosen Peter , Lin Chia‐Chi , Mahoney John , Modi Sanjiv , Lee Peter , Ernstoff Marc S. , Su Wu‐Chou , Spira Alexander , Pilz Korinna , Vinisko Richard , Schloss Charles , Fritsch Holger , Zhao Charles , Carducci Michael A.
Published: December 2013

BACKGROUND

Polo‐like kinases (Plks) control multiple steps during the cell cycle, and Plk1 is overexpressed in urothelial cancer (UC). Volasertib (BI 6727), a Plk inhibitor, has demonstrated antitumor activity in several malignancies, including UC. In this phase 2 trial, the authors investigated volasertib as a second‐line treatment in advanced/metastatic UC.

METHODS

Patients who progressed within 2 years of 1 prior chemotherapy regimen received 300 mg volasertib on day 1 every 3 weeks. The dose was escalated to 350 mg in cycle 2 if volasertib was tolerated in cycle 1. The primary endpoint was tumor response, which was assessed every 6 weeks; secondary endpoints were progression‐free survival, overall survival, duration of response, safety, and pharmacokinetics.

RESULTS

Fifty patients were enrolled, and the median patient age was 68.5 years (range, 52‐83 years). All patients had received prior platinum, 94% of patients had relapsed ≤2 years after prior therapy, 36% had liver metastases, and 54% had lung metastases. The median number of treatment cycles was 2 (range, 1‐27 treatment cycles), and 23 patients were dose escalated at cycle 2. Seven patients (14%) had a partial response, 13 (26%) had stable disease, and 30 (60%) progressed within 6 weeks. The median response duration was 41 weeks (range, 29.1‐77.3 weeks). The median progression‐free survival was 1.4 months, and the median overall survival was 8.5 months. The most frequent grade 3 and 4 adverse events were neutropenia (28%), thrombocytopenia (20%), and anemia (16%). No cumulative toxicity was observed.

CONCLUSIONS

Volasertib as second‐line treatment for advanced/metastatic UC had an acceptable safety profile but demonstrated insufficient antitumor activity for further evaluation as a monotherapy. Cancer 2014;120:976–982. © 2013 American Cancer Society.
Human papillomavirus (HPV) assays for testing fine‐needle aspiration specimens in patients with head and neck squamous cell carcinoma
Authors: Faquin William C.
Published: December 2013

Human papillomavirus (HPV)‐related head and neck squamous cell carcinoma is frequently diagnosed by fine‐needle aspiration, and accurate methods for confirming high‐risk HPV types in these cytologic specimens are needed. Authors in this issue demonstrate the validity of the Cervista HPV assays for identifying these HPV types.
Cervista HPV assays for fine‐needle aspiration specimens are a valid option for human papillomavirus testing in patients with oropharyngeal carcinoma
Authors: Guo Ming , Khanna Abha , Dhillon Jasreman , Patel Shobha J. , Feng Jie , Williams Michelle D. , Bell Diana M. , Gong Yun , Katz Ruth L. , Sturgis Erich M. , Staerkel Gregg A.
Published: December 2013

BACKGROUND

The objectives of this study were to evaluate the validity of Cervista human papillomavirus (HPV) assays in head and neck fine‐needle aspiration (FNA) specimens from patients with head and neck squamous carcinomas and to verify that the Cervista assay in FNA specimens is a valid option for determining HPV status in patients with oropharyngeal carcinomas.

METHODS

The authors retrospectively retrieved 64 head and neck FNA specimens from patients who had head and neck squamous carcinoma. The specimens were tested for HPV types 16 and 18 (HPV16/18) and for high‐risk (HR) HPV DNA using the Cervista HPV16/18 and HPV HR assays, respectively. The results from those assays were compared with the results from polymerase chain reaction (PCR)‐based HPV assays in the same tissues and with the results from HPV in situ hybridization assays/p16 immunostaining in the corresponding primary tumors.

RESULTS

In total, 64 FNA specimens were analyzed. The Cervista HPV16/18 and/or HPV HR assays were positive in 48 of 64 specimens (75%), and there was a predominance of HPV16 (42 of 48 specimens; 88%). In the 49 specimens that had PCR‐based test results, overall agreement with Cervista assay results was 96% (47 of 49 specimens; κ = 0.883). In the 49 specimens that had PCR‐based HPV16/18 genotyping results, overall agreement with the Cervista HPV16/18 results was 94% (46 of 49 specimens; κ = 0.847). In the 36 primary carcinoma specimens that had valid HPV in situ hybridization/p16 immunostaining results, overall agreement with the Cervista assay results was 92% (33 of 36 specimens; κ = 0.679).

CONCLUSIONS

Cervista HPV16/18 and Cervista HPV HR testing of head and neck FNA specimens is a valid option for determining HPV16/18 status in patients with oropharyngeal carcinoma. Cancer (Cancer Cytopathol) 2014;122:96–103. © 2013 American Cancer Society.
Distribution of vesicular glutamate transporter 2 in auditory and song control brain regions in the adult zebra finch (Taeniopygia guttata)
Authors: Karim Mohammad Rabiul , Saito Shouichiro , Atoji Yasuro
Published: December 2013

The songbird brain has a system of interconnected nuclei that are specialized for singing and song learning. Wada et al. (2004; J. Comp. Neurol. 476:44–64) found a unique distribution of the mRNAs for glutamate receptor subunits in the song control brain areas of songbirds. In conjunction with data from electrophysiological studies, these finding indicate a role for the glutamatergic neurons and circuits in the song system. This study examines vesicular glutamate transporter 2 (VGLUT2) mRNA and protein expression in the zebra finch brain, particularly in auditory areas and song nuclei. In situ hybridization assays for VGLUT2 mRNA revealed high levels of expression in the ascending auditory nuclei (magnocellular, angular, and laminar nuclei; dorsal part of the lateral mesencephalic nucleus; ovoidal nucleus), high or moderate levels of expression in the telencephalic auditory areas (cudomedial mesopallium, field L, caudomedial nidopallium), and expression in the song nuclei (HVC, lateral magnocellular nucleus of the anterior nidopallium, robust nucleus of the arcopallium), where levels of expression were greater than in the surrounding brain subdivisions. Area X did not show expression of VGLUT2 mRNA. Nuclei in the descending motor pathway (dorsomedial nucleus of the intercollicular complex, retroambigual nucleus, tracheosyringeal motor nucleus of the hypoglossal nerve) expressed VGLUT2 mRNA. The target nuclei of VGLUT2 mRNA‐expressing nuclei showed immunoreactivity for VGLUT2 as well as hybridization signals for the mRNA of glutamate receptor subunits. The present findings demonstrate the origins and targets of glutamatergic neurons and indicate a central role for glutamatergic circuits in the auditory and song systems in songbirds. J. Comp. Neurol. 522:2129–2151, 2014. © 2013 Wiley Periodicals, Inc.
Fluorescent Nanodiamonds with Bioorthogonally Reactive Protein‐Resistant Polymeric Coatings
Authors: Rehor Ivan , Mackova Hana , Filippov Sergey K. , Kucka Jan , Proks Vladimir , Slegerova Jitka , Turner Stuart , Van Tendeloo Gustaaf , Ledvina Miroslav , Hruby Martin , Cigler Petr
Published: December 2013

The novel synthesis of a polymeric interface grown from the surface of bright fluorescent nanodiamonds is reported. The polymer enables bioorthogonal attachment of various molecules by click chemistry; the particles are resistant to nonspecific protein adsorption and show outstanding colloidal stability in buffers and biological media. The coating fully preserves the unique optical properties of the nitrogen‐vacancy centers that are crucial for bioimaging and sensoric applications.
Vagal regulation and internalizing psychopathology among adolescents exposed to childhood adversity
Authors: McLaughlin Katie A. , Alves Sonia , Sheridan Margaret A.
Published: December 2013

Childhood adversity (CA) is strongly associated with youth psychopathology. Identifying factors that reduce vulnerability following CA is critical for developing preventive interventions. Vagal tone and vagal reactivity following psychosocial stressors might influence psychopathology among youths exposed to CA. We acquired heart period and impedance cardiography data to calculate respiratory sinus arrhythmia (RSA) and preejection period (PEP) from 157 adolescents aged 13–17 years at rest and during the Trier Social Stress Test (TSST). Internalizing and externalizing symptoms and multiple forms of CA were assessed. Resting RSA and RSA reactivity interacted with CA in predicting internalizing but not externalizing psychopathology; CA was unassociated with internalizing problems in adolescents with high resting RSA and RSA reactivity. No interactions were observed with PEP. High resting RSA predicted greater vagal rebound and accelerated heart rate recovery following the TSST, highlighting one potential mechanism underlying low internalizing symptoms following CA among youths with high vagal tone. © 2013 Wiley Periodicals, Inc. Dev Psychobiol 56: 1036–1051, 2014.