bluuebunny/crossref_metadata_2025 huggingface dataset:
Micro‐ and Nanostructures of Photoelectrodes for Solar‐Driven Water Splitting
Authors: Zhang Peng , Gao Lian , Song Xuefeng , Sun Jing
Published: September 2014

Artificial photosynthesis of clean fuels has aroused great interest to meet the great demand for clean and renewable energy. Great advances have recently been made in various photoelectrodes with their efficiencies and stabilities significantly improved by the design and implementation of novel structures, which are determinative for the optical absorption, charge‐transport path, surface area, and electronic conductivity. This Research News article discusses perspectives of the synthetic methods and micro‐ and nanostructures (planar structures, 1D structures, and mesoporous structures) of photoelectrodes, and their relationships with the photo‐electrochemical performance. Structural features, such as particle size, crystallinity, morphology, and film thickness, as well as the trade‐offs among them are also evaluated and discussed for each category of structure.
Lossen Rearrangements under Heck Reaction Conditions
Authors: AbdelHafez El‐Shimaa M. N. , Aly Omar M. , Abuo‐Rahma Gamal El‐Din A. A. , King S. Bruce
Published: September 2014

The classical Lossen rearrangement converts activated hydroxamic acids to isocyanates that form numerous products upon their reaction with nucleophiles. We report a simple and highly efficient method of using Heck reaction conditions to initiate Lossen rearrangements of hydroxamic acids. In addition, Lossen rearrangements occur in the presence of palladium(II) acetate or triethylamine, components of the Heck reaction, alone. A potential mechanism is provided to explain this reactivity and these results show that Heck reactions and Lossen rearrangements occur under the same conditions and may provide new methods for facile initiation of Lossen rearrangements.

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Synthesis of 5‐(Fluoromethyl)‐4,5‐dihydroisoxazoles by Silver‐ Catalyzed Oxyfluorination of Unactivated Alkenes
Authors: Liu Yan‐Yun , Yang Ji , Song Ren‐Jie , Li Jin‐Heng
Published: September 2014

A new silver‐catalyzed oxyfluorination of unactivated alkenes using commercially available Selectfluor as the fluorine source is presented. This method provides a new access to 5‐(fluoromethyl)‐4,5‐dihydroisoxazoles, and represents a new example of alkene 1,2‐difunctionalization by simultaneously forming two new carbon‐heteroatom bonds.

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Iodine‐Promoted Sequential C(sp3)H Functionalization Reactions: An Annulation Strategy for the Construction of 3‐Methylthio‐4‐arylmaleimides
Authors: Gao Qinghe , Wu Xia , Li Yuhong , Liu Shan , Meng Xianggao , Wu Anxin
Published: September 2014

A new process has been developed for the iodine‐promoted sequential C(sp3)H bond functionalization of methyl ketones and acetamides. This reaction represents a novel annulation strategy for the synthesis of 3‐(methylthio)‐4‐aryl‐1H‐pyrrole‐2,5‐diones, and involves an α‐ketoimide as the key intermediate. Furthermore, DMSO was converted to DMS in situ, which served as the methylthiolation reagent in the reaction. This protocol constitutes an efficient and convenient method for the methylthiolation of substrates bearing a wide range of functional groups.

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Microfabricated Pseudocapacitors Using Ni(OH)2 Electrodes Exhibit Remarkable Volumetric Capacitance and Energy Density
Authors: Kurra Narendra , Alhebshi Nuha A. , Alshareef H. N.
Published: September 2014

Metal hydroxide based microfabricated pseudocapacitors with impressive volumetric stack capacitance and energy density are demonstrated. A combination of top‐down photolithographic process and bottom‐up chemical synthesis is employed to fabricate the micro‐pseudocapacitors (μ‐pseudocapacitors). The resulting Ni(OH)2‐based devices show several excellent characteristics including high‐rate redox activity up to 500 V s–1 and an areal cell capacitance of 16 mF cm–2 corresponding to a volumetric stack capacitance of 325 F cm–3. This volumetric capacitance is two‐fold higher than carbon and metal oxide based μ‐supercapacitors with interdigitated electrode architecture. Furthermore, these μ‐pseudocapacitors show a maximum energy density of 21 mWh cm–3, which is superior to the Li‐based thin film batteries. The heterogeneous growth of Ni(OH)2 over the Ni surface during the chemical bath deposition is found to be the key parameter in the formation of uniform monolithic Ni(OH)2 mesoporous nanosheets with vertical orientation, responsible for the remarkable properties of the fabricated devices. Additionally, functional tandem configurations of the μ‐pseudocapacitors are shown to be capable of powering a light‐emitting diode.
Amyloid‐β efflux from the central nervous system into the plasma
Authors: Roberts Kaleigh Filisa , Elbert Donald L. , Kasten Tom P. , Patterson Bruce W. , Sigurdson Wendy C. , Connors Rose E. , Ovod Vitaliy , Munsell Ling Y. , Mawuenyega Kwasi G. , Miller‐Thomas Michelle M. , Moran Christopher J. , Cross Dewitte T. , Derdeyn Colin P. , Bateman Randall J.
Published: September 2014

Objective

The aim of this study was to measure the flux of amyloid‐β (Aβ) across the human cerebral capillary bed to determine whether transport into the blood is a significant mechanism of clearance for Aβ produced in the central nervous system (CNS).

Methods

Time‐matched blood samples were simultaneously collected from a cerebral vein (including the sigmoid sinus, inferior petrosal sinus, and the internal jugular vein), femoral vein, and radial artery of patients undergoing inferior petrosal sinus sampling. For each plasma sample, Aβ concentration was assessed by 3 assays, and the venous to arterial Aβ concentration ratios were determined.

Results

Aβ concentration was increased by ∼7.5% in venous blood leaving the CNS capillary bed compared to arterial blood, indicating efflux from the CNS into the peripheral blood (p < 0.0001). There was no difference in peripheral venous Aβ concentration compared to arterial blood concentration.

Interpretation

Our results are consistent with clearance of CNS‐derived Aβ into the venous blood supply with no increase from a peripheral capillary bed. Modeling these results suggests that direct transport of Aβ across the blood–brain barrier accounts for ∼25% of Aβ clearance, and reabsorption of cerebrospinal fluid Aβ accounts for ∼25% of the total CNS Aβ clearance in humans. Ann Neurol 2014;76:837–844
Band gaps and optical spectra from single‐ and double‐layer fluorographene to graphite fluoride: many‐body effects and excitonic states
Authors: Karlický František , Otyepka Michal
Published: September 2014

First‐principle band gaps and optical absorption spectra of single‐ and double‐layer fluorographene with bulk graphite fluoride are compared. The electronic properties are calculated using the many‐body GW approximation and the optical spectra using the Bethe‐Salpeter equation (BSE). The inclusion of electron‐hole interactions is crucial for predicting low energy excitonic absorption peaks. The position of the first exciton peak is identical in single‐, double‐ and multilayer fluorographene, which may indicate that the onset of the absorption spectra does not differ in these materials.
Preparation and dielectric properties of (Ba0.5Sr0.4Ca0.1)TiO3/polystyrene composites
Authors: Zhang Liang , Zhao Jun , Huang Er‐Quan , Zha Jun‐Wei , Dang Zhi‐Min
Published: September 2014

Polymer composites with polystyrene (PS) as matrix and (Ba0.5Sr0.4Ca0.1)TiO3 (BSCT) as fillers are prepared by solution casting method. It is found that the dielectric constant of the prepared BSCT/PS composites increases with increasing filler content over the frequency range from 100 Hz to 500 MHz. And the dielectric properties of the composites show a good temperature independency over the range of −30°C to 80°C. For the composite with 50 vol % filler content, the dielectric constant and dielectric loss are comparable with the literature values reported for other PS composites used for microwave substrate. Several theoretical models are used to compare with the experimental data of the dielectric constant of the composites. The microstructure and thermal properties of the composites were also studied. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41398.
Operating window of solution casting. II. Non‐Newtonian fluids
Authors: Huang Yuan‐Chang , Wang Tai‐Zan , Liu Ta‐Jo , Tiu Carlos
Published: September 2014

The operating windows of the solution casting of two polymeric liquids were evaluated experimentally. The experimental setup and procedure were the same as used previously for the casting of Newtonian fluids (Journal of Applied Polymer Science 2013, 129, 507–516). Aqueous carboxymethylcellulose/glycerol solutions exhibited pure shear‐thinning behavior at low polymer concentrations but became viscoelastic at high polymer concentrations, whereas polyacrylamide/glycerol solutions showed viscoelastic behavior over a wide range of concentrations. The shear‐thinning behavior, in conjunction with a low level of elasticity, of the casting solution was found to be useful in expanding the stable operating windows. However, an opposite effect on the operating windows was found for highly elastic solutions. The non‐Newtonian effect on the maximum stable casting speed was prominent only when the capillary number exceeded unity. Defects outside of the operating window were mostly similar to those observed in Newtonian solution casting. For highly concentrated solutions, a new rough surface defect was observed. This defect could be attributed to polymer chain entanglement, alignment, or breakup. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41411.
Morphology, structure, and properties of poly(lactic acid) microporous films containing poly(butylene terephthalate) fine fibers fabricated by biaxial stretching
Authors: Samthong Chavakorn , Seemork Jiraporn , Nobukawa Shogo , Yamaguchi Masayuki , Praserthdam Piyasan , Somwangthanaroj Anongnat
Published: September 2014

The effects of size and shape, i.e., sphere and fiber, of dispersed poly(butylene terephthalate) (PBT) in poly(lactic acid) (PLA) matrix on the morphology and porous structure of the biaxially stretched films are comparatively investigated. Scanning electron microscope results confirm that the PBT fine fibers can be produced by melt‐stretching following by fast quenching. Rheological characterization reveals the random network structure of PBT fibers. Further, the stretched films composed of spherical PBT particles show the ellipsoidal microvoids due to the interfacial debonding, and the void size relates to the particle size of PBT. However, size of PBT droplets does not influence the void content of the stretched films. The void content considerably increases for equibiaxial deformation as compared with planar deformation, particularly at high draw ratio. Additionally, the stretched films containing fibrous dispersion exhibit the nonaffine behavior and the highest void content of 8%, which is probably due to the localized deformation between fibers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41415.
Production of polyols and waterborne polyurethane dispersions from biodiesel‐derived crude glycerol
Authors: Hu Shengjun , Luo Xiaolan , Li Yebo
Published: September 2014

This study investigated the preparation of polyols and waterborne polyurethane dispersions (CG‐WPUDs) from biodiesel‐derived crude glycerol. The polyols were produced from biodiesel‐derived crude glycerol via a thermochemical conversion process, which converted crude glycerol components such as glycerol, free fatty acids, and methyl esters of fatty acids (FAMEs) into polyols under optimized reaction conditions. CG‐WPUDs with different hard segments (41.0% to 63.2 wt %) were prepared from the crude glycerol‐based polyols produced. PU coating films cast from CG‐WPUDs showed increasing glass transition temperatures (Tg) from 63°C to 81°C when hard segment content increased from 41.0% to 63.2% and had good thermal stability up to 240°C. CG‐WPUD‐based coatings showed excellent adhesion to steel panel surfaces, pencil hardness as high as F, but relatively low flexibility. This study demonstrated the potential of biodiesel‐derived crude glycerol for the production of bio‐based polyols and WPUDs. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41425.
Membrane adsorbers comprising grafted glycopolymers for targeted lectin binding
Authors: Chenette Heather C. S. , Husson Scott M.
Published: September 2014

This work details the design and testing of affinity membrane adsorbers for lectin purifications that incorporate glucose‐containing glycopolymers. It is the selective interaction between the sugar residues of the glycopolymer and the complementary carbohydrate‐binding domain of the lectin that provides the basis for the isolation and purification of lectins from complex biological media. The design approach used in these studies was to graft glycopolymer ‘tentacles’ from macroporous regenerated cellulose membranes by atom transfer radical polymerization. As shown in earlier studies, this design approach can be used to prepare high‐productivity membrane adsorbers. The model lectin, concanavalin A (conA), was used to evaluate membrane performance in bind‐and‐elute purification, using a low‐molecular‐weight sugar for elution. The membrane capacity for binding conA was measured at equilibrium and under dynamic conditions using flow rates of 0.1 and 1.0 mL/min. The first Damkohler number was estimated to relate the adsorption rate to the convective mass transport rate through the membrane bed. It was used to assess whether adsorption kinetics or mass transport contributed the primary limitation to conA binding. Analyses indicate that this system is not limited by the accessibility of the binding sites, but by the inherent rate of adsorption of conA onto the glycopolymer. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41437.
Preparation, morphology, and conductivity of waterborne, nanostructured, cationic polyurethane/polypyrrole conductive coatings
Authors: Wang Haihua , Liu Yun , Fei Guiqiang , Lan Jing
Published: September 2014

To endow cellulose fiber papers with good conductivity and simultaneously retain the mechanical strength of the conductive paper, a kind of waterborne, nanostructured, cationic polyurethane (CPU)/polypyrrole (PPy) conductive coatings were developed to modify the paper surface. Fourier transform infrared spectroscopy, atomic force microscopy, and thermogravimetry–differential thermogravimetry demonstrated that the peak associated with hydrogen bonding between NH and CO of CPU was shifted, and chemical bonds between CPU and PPy were formed. Good compatibility between CPU and PPy was simultaneously established. Transmission electron microscopy and atomic force microscopy also suggested that PPy was encased and embedded in the CPU colloidal particles in a uniform style, and the surface of the CPU/PPy film was covered with a smooth, coherent conductive layer. With increasing pyrrole (Py) content from 5 to 20 wt %, the particle size increased from 55.08 to 74.59 nm, and the dispersity index (DPI) decreased. In addition, the conductivity of CPU/PPy increased from 0.1 to 5.0 S/cm. When the Py content was greater than 20 wt %, apparent increases in the particle size and DPI were detected as was particle coagulation; this resulted in decreased conductivity. Compared with the uncoated paper, the paper coated with CPU/PPy dispersions displayed different surface morphologies. The surface of the paper was completely enwrapped by the CPU/PPy conductive films when the coating amount was 45.42 g/m2. With increasing coating amounts from 10.35 to 67.86 g/m2, the conductivity of the conductive coated paper increased from 2.78 × 10−3 to 2.16 S/cm, the tensile strength increased from 35.3 to 60.4 N m/g, and the conductive coated paper displayed good conductivity stability. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41445.
Kalman Filtering Over Lossy Networks Under Switching Sensors
Authors: You Keyou , Sui Tianju , Fu Minyue
Published: September 2014

In this paper, we study the mean square stability of Kalman filtering of a discrete‐time stochastic system under two periodically switching sensors. The sensor measurements are sent to a remote estimator over a lossy channel whose packet loss process is independent and identically distributed. We prove that the problem can be converted into the stability analysis of Kalman filtering using two sensors at each time, and the measurements of each sensor are transmitted to the estimator via an independent lossy channel of the same packet loss rate. Some necessary and/or sufficient conditions for stability of the estimation error covariance matrices are derived. Moreover, the effect of the sensor switching on the filter stability is revealed. Their implications and relationships with related results in the literature are discussed.
Synchronization Criterion and Control Scheme for Lur'e Type Complex Dynamical Networks with Switching Topology and Coupling Time‐Varying Delay
Authors: Zhang Youjian , Li Peiran , Yang Qiang , Yan Wenjun
Published: September 2014

In this paper, the synchronization problem is addressed in the context of Lur'e type complex switched network (CSN) with coupling time‐varying delay in which every node is a Lur'e system. Based on the Lyapunov–Krasovskii theory and linear matrix inequality (LMI) technique, a delay‐dependent synchronization criterion and a decentralized state feedback dynamic controller for synchronization of CSNs have been proposed. By choosing a common Lyapunov–Krasovskii functional and using the combined reciprocal convex technique, some previously ignored terms can be reconsidered and less conservative conditions can be obtained. In addition, by using an eigenvalue‐decoupling method and convex optimization theory, high‐dimension LMIs are decoupled into a set of low‐dimension ones and the computation complexity of the criterion can be significantly reduced. The effectiveness and applicability of the suggested control solution is verified and assessed through the analysis for two numerical examples.
Illusions of Learning: Irrelevant Emotions Inflate Judgments of Learning
Authors: Baumeister Roy F. , Alquist Jessica L. , Vohs Kathleen D.
Published: September 2014

People use assessments of how much they have learned to choose and recommend instructors, seminars, and weekend trips. How do people assess how much they have learned? Recent theorizing has depicted emotion as a cue for learning, and so people may be misled by recent emotional states to infer that they have learned more than they actually have. Four studies showed that people associated emotion with learning and believed, often falsely, that they learned more when in an emotional than unemotional state. Factual lessons were coupled with manipulations of arbitrary, irrelevant emotional states. Participants rated that they learned more after an emotion had been induced than in emotionally neutral control conditions. These differences remained significant after controlling for actual learning as measured by objective tests, which was unaffected by emotion. This illusion of learning caused by emotion was robust with respect to changes of procedure and sample, including whether the emotion came before or after the information to be learned. Alternative explanations were ruled out, including that emotion would intensify ratings generally, that emotion would make incoming information seem particularly personally relevant, that emotion increased engagement in the research, and that illusory learning would depend on retrospective exaggeration of one's prior ignorance. Because irrelevant emotions can increase people's judgments that they have learned something, incidental emotional experiences could increase a person's likelihood of deciding to take another class with a particular instructor, to sign up for another leadership seminar, or to engage in a risky (but emotion‐filled) excursion. Copyright © 2014 John Wiley & Sons, Ltd.
Extremely low frequency magnetic fields inhibit adipogenesis of human mesenchymal stem cells
Authors: Du Leilei , Fan Hongye , Miao Huishuang , Zhao Guangfeng , Hou Yayi
Published: September 2014

It was reported that obese (Ob/Ob) mice lose their weight and fat when treated with 0.5 T direct current electromagnetic fields. We also observed that 7.5 Hz, 0.4 T rotation of extremely low frequency magnetic fields (ELF‐MF) has an inhibitory effect on obesity. Mesenchymal stem cells (MSCs) are multi‐potent cells capable of differentiating to different MSC lineages, including adipose. We hypothesized that inhibitory effects of ELF‐MF on obesity may be related to the differentiation of MSCs to adipocytes. In the present study, we investigated the effects of 7.5 Hz, 0.4 T ELF‐MF on differentiation of human umbilical cord MSCs. We found that ELF‐MF inhibited adipogenic differentiation (exposed 2 h/day for 15 days) of MSCs but had no effect on osteogenic differentiation (exposed 2 h/day for 21 days). Moreover, ELF‐MF inhibited adipocyte‐specific expression of peroxisome proliferator‐activated receptor 2 (PPARγ2). ELF‐MF promoted c‐Jun N‐terminal kinase (JNK)‐dependent intracellular signaling in MSCs. Furthermore, activation of the non‐canonical Wnt pathway provoked the inhibition of PPARγ2 expression resulting in suppression of adipogenic differentiation. In addition, the effects of ELF‐MF on growth and apoptosis of MSCs were not observed. Our data indicated that ELF‐MF of 7.5 Hz, 0.4 T inhibited the adipogenic differentiation of MSCs via JNK‐dependent Wnt signaling pathway, but had no effect on the growth and function of MSCs, suggesting the inhibitory effect of ELF‐MF on obesity may be attributed to the inhibition of differentiation of MSCs into adipocytes. This study may provide a potential approach for the treatment of obesity. Bioelectromagnetics. 35:519–530, 2014. © 2014 Wiley Periodicals, Inc.
Fluorescent Protein Biosensor for Probing CDK/Cyclin Activity in vitro and in Living Cells
Authors: Van Thi Nhu Ngoc , Pellerano Morgan , Lykaso Sophie , Morris May C.
Published: September 2014

Cyclin‐dependent kinases (CDKs) play an essential role in the coordination of cell cycle progression and transcriptional regulation; hyperactivation is associated with cancer. However there are few means of measuring their activity in a physiological context or their inhibition in response to therapeutics. To this aim we engineered a modular fluorescent protein biosensor that reports on phosphorylation by CDK/cyclins through real‐time changes in fluorescence intensity. This allowed a comparison of enzymatic activity of recombinant kinases, monitoring inhibition by small molecules, and probing endogenous activities in lysates from healthy and cancer cell lines in a sensitive and quantitative fashion. This versatile tool was further implemented to probe the oscillatory activity of these kinases throughout the cell cycle by time‐lapse imaging and ratiometric fluorescence quantification, following delivery of a red fluorescent protein fusion mediated by cell‐penetrating peptides.
Chemically Unprecedented Biocatalytic (AuaG) Retro‐[2,3]‐Wittig Rearrangement: A New Insight into Aurachin B Biosynthesis
Authors: Katsuyama Yohei , Li Xu‐Wen , Müller Rolf , Nay Bastien
Published: September 2014

AuaG is flavin‐dependent monooxygenase responsible for the conversion of aurachin C to aurachin B, a reaction thought to resemble semipinacol migration of the farnesyl substituent. A study of the substrate tolerance of AuaG reveals that it has the peculiar ability to oxidise short‐chain analogues of aurachin D. Unexpectedly, a novel retro‐[2,3]‐Wittig rearrangement was observed with an isoprenyl substrate analogue, thus leading to the 1,1‐dimethylallyl ether. Additionally, we found that saturated‐chain analogues of N‐oxidised aurachin C were not transformed by the C3→C4 semipinacol reaction, as might have been expected for such substrates. Based on this and the unique retro‐[2,3]‐Wittig rearrangement, we discuss an alternative biosynthetic route for the conversion of aurachin C to aurachin B.
Predictors and clinical impact of pre‐existing and acquired thrombocytopenia following transcatheter aortic valve replacement
Authors: Flaherty Michael P. , Mohsen Amr , Moore Joseph B. , Bartoli Carlo R. , Schneibel Erik , Rawasia Wasiq , Williams Matthew L. , Grubb Kendra J. , Hirsch Glenn A.
Published: September 2014

Background

Data are limited regarding transcatheter aortic valve replacement (TAVR)‐related thrombocytopenia (TP). We sought to thoroughly characterize the presence, clinical impact, and severity of TP associated with TAVR.

Methods and Results

Data were collected from 90 patients who underwent TAVR using the Edwards SAPIEN valve (59 TF, 29 TA, 2 Tao). Platelet counts were evaluated peri‐procedurally and for 8 days following TAVR. Platelet levels were compared and patients were divided into a no TP (No‐TP) group 1, acquired (new) TP (NTP) group 2, pre‐existing (pre‐TAVR) TP (PTP) group 3, and further stratified based on the severity of TP: mild (M) TP (100–149 × 103 cell/µL) and moderate–severe (MS) TP (<100 × 103 cell/µL). Pre‐TAVR point prevalence and post‐TAVR incidence of TP were 40% and 79%, respectively (P < 0.001); nadir platelet count in all groups occurred day 4 post‐TAVR. Baseline predictors for developing MS TP in groups 2–3 included baseline TP, leaner body mass, smaller pre‐procedural aortic valve area, higher peak aortic jet velocity, and worsening baseline renal function. Development of “major” TP (nadir platelet count <100 × 103 cell/µL, ≥50% decrease) predicted a higher risk of major vascular complications (OR 2.78 [95% CI, 1.58–3.82]) and major bleeding (OR 3.18 [95% CI, 1.33–5.42]) in group 3.

Conclusion

TAVR‐related TP is predictable and classification by PTP and TP severity prior to TAVR allows for better risk stratification in predicting in‐hospital clinical outcomes. Major TP in the presence of worsening TP is predictable and is associated with worse clinical outcomes. © 2014 Wiley Periodicals, Inc.
Understanding Nano‐Impacts: Binary Nature of Charge Transfer during Mediated Reactions
Authors: Kätelhön Enno , Compton Richard G.
Published: September 2014

We report mediated charge transfer across a nanoparticle that Faradaically interacts with its surrounding solution while impacting on an electrochemically inactive electrode. To this end, two different aspects of the process are elucidated and interconnected: The Faradaic reaction at the particle surface and electron tunnelling between the electrode and the particle. Results demonstrate that the charge transfer can be described through a binary model, in which the current switches between the limiting Faradaic current and no current at all as a function of the electrode–particle distance, while the response is largely unrelated to the analyte’s formal potential. This finding allows a significantly simplified modelling approach in future studies.
Self‐Assembled Supramolecular Hetero‐Bimetallacycles for Anticancer Potency by Intracellular Release
Authors: Mishra Anurag , Chang Lee Seung , Kaushik Neha , Cook Timothy R. , Choi Eun Ha , Kumar Kaushik Nagendra , Stang Peter J. , Chi Ki‐Whan
Published: September 2014

Two new tetracationic hetero‐bimetallacycles, compounds 4 and 5, have been constructed from an N,N′‐bis(4‐(pyridin‐4‐ylethynyl)phenyl)pyridine‐2,6‐dicarboxamide ligand (1), and cis‐blocked complexes [M(dppf)(OTf)2] (dppf=1,1′‐bis(diphenylphosphino)ferrocene; OTf=trifluoromethanesulfonate; M=Pd (2), Pt (3)) in CH3NO2/CH2Cl2 (1:1) solvent. Both complexes were isolated with adequate yields as triflate salts and were then characterized using 1H, 13C, and 31P NMR spectroscopy, elemental analysis, UV/Vis spectroscopy, and high‐resolution electrospray mass spectrometry (HR‐ESMS). The molecular structure of 4 was determined by molecular mechanics force‐field calculations. The cytotoxic effect of both new complexes were analyzed against T98G (brain tumor), KB (head and neck cancer), SNU‐80 (thyroid cancer), and HEK‐293 non‐malignant cell lines. The cytotoxicity of complexes 4 and 5 were found to be considerably more effective against cancer cells than reference drug cisplatin. Annexin‐V/PI staining, caspase‐3/7 activity, and the reduction in mitochondrial membrane potential justify a significant level of apoptosis in complex‐treated cells.
Tuning the Cellular Uptake Properties of Luminescent Heterobimetallic Iridium(III)–Ruthenium(II) DNA Imaging Probes
Authors: Wragg Ashley , Gill Martin R. , Turton David , Adams Harry , Roseveare Thomas M. , Smythe Carl , Su Xiaodi , Thomas Jim A.
Published: September 2014

The synthesis of two new luminescent dinuclear IrIII–RuII complexes containing tetrapyrido[3,2‐a:2′,3′‐c:3′′,2′′‐h:2′′′,3′′′‐j]phenazine (tpphz) as the bridging ligand is reported. Unlike many other complexes incorporating cyclometalated IrIII moieties, these complexes display good water solubility, allowing the first cell‐based study on IrIII–RuII bioprobes to be carried out. Photophysical studies indicate that emission from each complex is from a RuII excited state and both complexes display significant in vitro DNA‐binding affinities. Cellular studies show that each complex is rapidly internalised by HeLa cells, in which they function as luminescent nuclear DNA‐imaging agents for confocal microscopy. Furthermore, the uptake and nuclear targeting properties of the complex incorporating cyclometalating 2‐(4‐fluorophenyl)pyridine ligands around its IrIII centre is enhanced in comparison to the non‐fluorinated analogue, indicating that fluorination may provide a route to promote cell uptake of transition‐metal bioprobes.
Nucleoside Mono‐ and Diphosphate Prodrugs of 2′,3′‐Dideoxyuridine and 2′,3′‐Dideoxy‐2′,3′‐didehydrouridine
Authors: Pertenbreiter Florian , Balzarini Jan , Meier Chris
Published: September 2014

Despite their close structural similarity to nucleoside analogues such as the anti‐HIV drugs AZT and d4T, 2′,3′‐dideoxyuridine (ddU) and 2′,3′‐dideoxy‐2′,3′‐didehydrouridine (d4U) are entirely inactive against HIV in their nucleoside form. However, it has been shown that the corresponding triphosphates of these two nucleosides can effectively block HIV reverse transcriptase. Herein we report on two types of nucleotide prodrugs (cycloSal and DiPPro nucleotides) of ddU and d4U to investigate their ability to overcome insufficient intracellular phosphorylation, which may be the reason behind their low anti‐HIV activity. The release of the corresponding mono‐ and diphosphates from these compounds was demonstrated by hydrolysis studies in phosphate buffer (pH 7.3) and human CD4+ T‐lymphocyte CEM cell extracts. Surprisingly, however, these compounds showed low or no anti‐HIV activity in tests with human CD4+ T‐lymphocyte CEM cells. Studies of the conversion of ddUDP and d4UDP into their triphosphate metabolites by nucleoside diphosphate kinase (NDPK) showed nearly no conversion of either diphosphate, which may be the reason for low intracellular triphosphate levels that result in low antiviral activity.
Attitudes toward molecular testing for personalized cancer therapy
Authors: Yusuf Rafeek A. , Rogith Deevakar , Hovick Shelly R. A. , Peterson Susan K. , Burton‐Chase Allison M. , Fellman Bryan M. , Li Yisheng , McKinney Carolyn , Bernstam Elmer V. , Meric‐Bernstam Funda
Published: September 2014

BACKGROUND

This study assessed attitudes of breast cancer patients toward molecular testing for personalized therapy and research.

METHODS

A questionnaire was given to female breast cancer patients presenting to a cancer center. Associations between demographic and clinical variables and attitudes toward molecular testing were evaluated.

RESULTS

Three hundred eight patients were approached, and 100 completed the questionnaire (a 32% response rate). Most participants were willing to undergo molecular testing to assist in the selection of approved drugs (81%) and experimental therapy (59%) if testing was covered by insurance. Most participants were white (71%). Even if testing was financially covered, nonwhite participants were less willing to undergo molecular testing for the selection of approved drugs (54% of nonwhites vs 90% of whites, odds ratio [OR] = 0.13, P = .0004) or experimental drugs (35% vs 68%, OR = 0.26, P = .0072). Most participants (75%) were willing to undergo a biopsy to guide therapy, and 46% were willing to undergo research biopsies. Nonwhite participants were less willing to undergo research biopsies (17% vs 55%, OR = 0.17, P = .0033). Most participants wanted to be informed when research results had implications for treatment (91%), new cancer risk (90%), and other preventable/treatable diseases (87%).

CONCLUSIONS

Most patients were willing to undergo molecular testing and minimally invasive procedures to guide approved or experimental therapy. There were significant differences in attitudes toward molecular testing between racial groups; nonwhites were less willing to undergo testing even if the results would guide their own therapy. Novel approaches are needed to prevent disparities in the delivery of genomically informed care and to increase minority participation in biomarker‐driven trials. Cancer 2015;121:243–50. © 2014 American Cancer Society.
Provider‐based research networks may improve early access to innovative colon cancer treatment for African Americans treated in the community
Authors: Penn Dolly C. , Chang YunKyung , Meyer Anne‐Marie , DeFilippo Mack Christina , Sanoff Hanna K. , Stitzenberg Karyn B. , Carpenter William R.
Published: September 2014

BACKGROUND

African American (AA) patients with colon cancer (CC) experience worse outcomes than whites partly due to differential treatment. The National Cancer Institute's Community Clinical Oncology Program (CCOP), a provider‐based research network, adopts and diffuses innovative CC treatments quickly. The authors hypothesized that CCOP participation would lessen racial differences in the receipt of oxaliplatin, an innovative treatment for CC, among patients with stage III CC in the community.

METHODS

Using Surveillance, Epidemiology, and End Results (SEER)‐Medicare data, the authors performed a population‐based retrospective cohort study of AA and white individuals aged ≥66 years who were diagnosed with AJCC stage III CC from 2003 through 2005. Generalized estimating equations were used to calculate the odds of receiving an oxaliplatin‐containing regimen. Predicted probabilities of oxaliplatin receipt for race‐CCOP combinations were calculated. The absolute difference in oxaliplatin receipt between races was estimated using the interaction contrast ratio.

RESULTS

Of 2971 included individuals, 36% received oxaliplatin, 29.5% were CCOP‐affiliated, and 7.6% were AA. On multivariate analysis, early diffusion of oxaliplatin was not found to be associated with race or CCOP participation. The probability of receiving oxaliplatin for AAs participating in a CCOP (0.46) was nearly double that of AAs who were not participating in a CCOP (0.25; P <.05). For white individuals, the probabilities of receiving oxaliplatin did not differ by CCOP participation. For oxaliplatin receipt, the joint effects assessment suggested a greater benefit of CCOP participation among AAs (interaction contrast ratio, 1.7).

CONCLUSIONS

Among older patients with stage III CC, there is a differential impact of race on oxaliplatin receipt depending on CCOP participation. AAs treated by CCOPs were more likely to receive oxaliplatin than AAs treated elsewhere. Provider‐based research networks may facilitate early access to innovative treatment for AAs with stage III CC. Cancer 2015;121:93–101. © 2014 American Cancer Society.
Connections of the commissural nucleus of Cajal in the goldfish, with special reference to the topographic organization of ascending visceral sensory pathways
Authors: Uezono Shiori , Yamada Yusuke , Kato Takeshi , Abe Hideki , Yamamoto Naoyuki
Published: September 2014

The primary general visceral nucleus of teleosts is called the commissural nucleus of Cajal (NCC). The NCC of goldfish has been divided into the medial (NCCm) and lateral (NCCl) subnuclei that receive inputs from subdiaphragmatic gastrointestinal tract and the posterior pharynx, respectively. Fiber connections of the NCC were examined by tract‐tracing methods in the goldfish Carassius auratus. Tracer injections into the NCC suggested that the NCC projects directly not only to the secondary visceral sensory region in the rhombencephalic isthmus and other brain stem centers, but also to the forebrain, similar to the situations in mammals, birds, and the Nile tilapia. Although fiber connections of the NCCm and NCCl were basically similar, the NCCm was the more important source of ascending general visceral fibers to the forebrain. Topographic organization was recognized regarding projections to the isthmic secondary visceral sensory zone; input from the NCCm is represented in the secondary general visceral sensory nucleus, while input from the NCCl in the lateral edge of the secondary gustatory nucleus. Moreover, specific injections into different regions of the vagal lobe revealed that the dorsomedio–ventrolateral axis of the lobe is represented in the lateromedial axis of the secondary gustatory nucleus. These observations suggest fine topographic organization of ascending visceral sensory pathways to the isthmic secondary centers. It should also be noted that the reception of primary afferents from the posterior pharynx and projections to the secondary gustatory nucleus suggest that the NCCl may be regarded as a gustatory rather than a general visceral sensory structure. J. Comp. Neurol. 523:209–225, 2015. © 2014 Wiley Periodicals, Inc.
Evaluation of Applicability of Compact Excitation Light Source to Detection of Thermally Grown Oxide Layer in Thermal Barrier Coating for Gas Turbines
Authors: Fukuchi Tetsuo , Eto Shuzo , Okada Mitsutoshi , Fujii Tomoharu
Published: September 2014

A compact, continuous wave laser was applied to detection of the thermally grown oxide (TGO) layer in a thermal barrier coating (TBC) for gas turbine high‐temperature components by photoluminescence. Experiments were conducted using TBC specimens heated in air to artificially produce a TGO layer. For specimens heated at 1100 °C, the photoluminescence intensity increased with heating time, whereas for specimens heated at 1000 °C, the photoluminescence intensity did not increase beyond 100 h. The results indicate that the formation of the TGO layer is strongly dependent on the temperature. In addition, scanning electron microscope (SEM) observations of the specimen cross section confirmed the formation of the TGO layer after heating for 100 h at 1100 °C. The applicability of a compact laser to TGO layer detection allows the development of a simple TGO detection system, which can be used in screening for the detailed inspection of delamination.
Toxicity of sulfate and chloride to early life stages of wild rice (Zizania palustris)
Authors: Fort Douglas J. , Mathis Michael B. , Walker Rachel , Tuominen Lindsey K. , Hansel Mike , Hall Scott , Richards Robin , Grattan S.R. , Anderson Kurt
Published: September 2014

Despite the importance of wild rice (Zizania palustris) in the Great Lakes region of North America, its sensitivity to sulfate is not well understood. A 21-d hydroponic experiment was performed to determine the toxicity of sulfate to wild rice seeds and seedlings. Effects of 6 sulfate concentrations ranging from 10 mg/L to 5000 mg/L and of chloride salts at equivalent conductivity were evaluated to determine whether adverse effects were attributable to sulfate or to conductivity-related stress. Sulfate treatment decreased root length, shoot length, and leaf number, and increased phytotoxic effects at concentrations of 5000 mg/L relative to a 50 mg/L control. The time to 30% mesocotyl emergence decreased at 2500 mg/L sulfate, indicating a potential stimulatory effect. Sulfate exposures of ≤5000 mg/L had no effect on 5 additional end points. Multiple regression analysis indicated that most observed changes could be attributed to conductivity-related stress rather than sulfate per se, with the exception of shoot length and leaf number. Chloride was more toxic than sulfate, as determined by root length and phytotoxicity. In summary, sulfate concentrations below 5000 mg/L did not adversely affect early–life stage wild rice during a 21-d period, and effects at 5000 mg/L sulfate were attributable to conductivity-related stress rather than sulfate toxicity in 2 of 4 end points. Environ Toxicol Chem 2014;33:2802–2809. © 2014 SETAC
Sponges as sentinels: Metal accumulation using transplanted sponges across a metal gradient
Authors: Davis Andrew R. , de Mestre Corrine , Maher William , Krikowa Frank , Broad Allison
Published: September 2014

To be effective sentinels, organisms must be able to be readily translocated to contamination hotspots. The authors sought to assess metal accumulation in genetically identical explants of a relatively common estuarine sponge, Suberites cf. diversicolor. Explants were transplanted to 7 locations across a metal contamination gradient in a large coastal estuary in southeastern Australia to establish, first, that explants of this species could be successfully translocated; second, that explants accumulated metals (cadmium, copper, lead, selenium, and zinc) sufficiently rapidly to be effective sentinels; third, that rates of metal accumulation in explants were in agreement with metal concentrations within sediments (<63-µm fraction) at each of the transplant locations; and finally, that changes in explant biomass correlated with overall metal load. Suberites were readily transplanted, with no mortality observed for the 2 mo of transplantation. Metal accumulation for lead, cadmium, and zinc was in close agreement with sediment metal concentrations, and explants showed dramatic increases in these metals in the heavily contaminated northern sections of the estuarine lake. No striking patterns were apparent for copper and selenium. Finally, growth was negatively correlated with total metal load and standardized total metal load in our explants. Taken together, these outcomes confirm that explants of this sponge are amenable to translocation and show considerable promise as biomonitors. Environ Toxicol Chem 2014;33:2818–2825. © 2014 SETAC
Newcastle disease virotherapy induces long‐term survival and tumor‐specific immune memory in orthotopic glioma through the induction of immunogenic cell death
Authors: Koks Carolien A. , Garg Abhishek D. , Ehrhardt Michael , Riva Matteo , Vandenberk Lien , Boon Louis , Vleeschouwer Steven De , Agostinis Patrizia , Graf Norbert , Van Gool Stefaan W.
Published: September 2014

The oncolytic features of several naturally oncolytic viruses have been shown on Glioblastoma Multiforme cell lines and in xenotransplant models. However, orthotopic glioma studies in immunocompetent animals are lacking. Here we investigated Newcastle disease virus (NDV) in the orthotopic, syngeneic murine GL261 model. Seven days after tumor induction, mice received NDV intratumorally. Treatment significantly prolonged median survival and 50% of animals showed long‐term survival. We demonstrated immunogenic cell death (ICD) induction in GL261 cells after NDV infection, comprising calreticulin surface exposure, release of HMGB1 and increased PMEL17 cancer antigen expression. Uniquely, we found absence of secreted ATP. NDV‐induced ICD occurred independently of caspase signaling and was blocked by Necrostatin‐1, suggesting the contribution of necroptosis. Autophagy induction following NDV infection of GL261 cells was demonstrated as well. In vivo, elevated infiltration of IFN‐γ+ T cells was observed in NDV‐treated tumors, along with reduced accumulation of myeloid derived suppressor cells. The importance of a functional adaptive immune system in this paradigm was demonstrated in immunodeficient Rag2−/− mice and in CD8+ T cell depleted animals, where NDV slightly prolonged survival, but failed to induce long‐term cure. Secondary tumor induction with GL261 cells or LLC cells in mice surviving long‐term after NDV treatment, demonstrated the induction of a long‐term, tumor‐specific immunological memory response by ND virotherapy. For the first time, we describe the therapeutic activity of NDV against GL261 tumors, evidenced in an orthotopic mouse model. The therapeutic effect relies on the induction of ICD in the tumor cells, which primes adaptive antitumor immunity.
Adjuvant chemotherapy for patients with primary hepatocellular carcinoma: A meta‐analysis
Authors: Zheng Zhouying , Liang Wenhua , Wang Dongping , Schroder Paul M. , Ju Weiqiang , Wu Linwei , Zheng Zheng , Shang Yushu , Guo Zhiyong , He Xiaoshun
Published: September 2014

Numerous studies have investigated the effects of adjuvant chemotherapy for primary hepatocellular carcinoma (HCC) patients. We conducted this analysis to evaluate the efficacy of adjuvant chemotherapy in HCC patients after hepatectomy. PubMed/MEDLINE, EMBASE, Cochrane, and other databases were searched for eligible studies. The major endpoints were overall survival (OS) and disease‐free survival (DFS). The pooled odds ratio (OR) was calculated using a random‐effects model to summarize the results. In the meta‐analysis of 13 randomized control trials (RCTs) and 35 observational studies with 4747 patients, hepatectomy plus adjuvant chemotherapy showed superiority over hepatectomy alone in 1‐year DFS (OR = 1.86, 1.38–2.51, p < 0.001), 3‐year DFS (OR = 2.37, 1.73–3.24, p < 0.001) and 5‐year DFS (OR = 1.99, 1.55–2.55, p < 0.001), as well as 1‐year OS (OR = 2.16, 95% confidence interval 1.75–2.68, p < 0.001), 3‐year OS (OR = 1.77, 1.48–2.13, p < 0.001) and 5‐year OS (OR = 1.92, 1.44–2.56, p < 0.001). Subgroup and sensitivity analysis revealed that only adjuvant TACE had significant survival benefits. The meta‐analysis of studies involving patients with portal vein tumor thrombus (PVTT), but not other factors related to recurrence risk, revealed favorable outcomes of the Treatment arm over the Control arm. The present study shows that adjuvant chemotherapy can improve outcomes for HCC patients. The benefits of adjuvant TACE have been confirmed whereas the effects of other adjuvant chemotherapy modalities remain uncertain. Adjuvant chemotherapy is likely to be more applicable to certain patient populations for instance those with PVTT, but further research in identifying these patient factors is of importance for tailoring adjuvant therapies to individual patients in the future.
Epithelial‐to‐Mesenchymal Transition Induced by TGF‐β1 Is Mediated by AP1‐Dependent EpCAM Expression in MCF‐7 Cells
Authors: Gao Jiujiao , Yan Qiu , Wang Jiao , Liu Shuai , Yang Xuesong
Published: September 2014

The epithelial‐to‐mesenchymal transition (EMT), a process involving the breakdown of cell–cell junctions and loss of epithelial polarity, is closely related to cancer metastasis and invasion. The epithelial cell adhesion molecule (EpCAM) is a type I transmembrane protein expressed in the majority of normal epithelial tissues and overexpressed in the majority of human epithelial cancers including breast cancer. EpCAM plays an important role in cancer progression. We showed that EpCAM participated in TGF‐β1‐induced EMT. TGF‐β1 treatment of MCF‐7 breast cancer cells was shown to induce EpCAM expression, which promoted the EMT and cell migration. EpCAM overexpression further enhanced TGF‐β1‐induced EMT and EpCAM knockdown inhibited TGF‐β1‐induced EMT. We further demonstrated that TGF‐β1 treatment induced the phosphorylation of JNK that was in turn responsible for the increased expression of Jun and Fos. This result suggests an important role of the JNK to AP‐1 signaling to EpCAM downstream of TGF‐β1 for the induction of EMT in the breast cancer cells. Collectively, our study highlights a novel function for EpCAM in TGF‐β1‐induced EMT process and suggests that targeting of EpCAM may be an attractive strategy to treat breast cancer. This study implicates the potential value of EpCAM as a molecular marker for breast cancer. J. Cell. Physiol. 230: 775–782, 2015. © 2014 Wiley Periodicals, Inc.
Cycle Transversals in Tournaments with Few Vertex Disjoint Cycles
Authors: Bang‐Jensen Jørgen , Bessy Stéphane
Published: September 2014

We prove that every tournament T with no three disjoint cycles contains a set X of at most four vertices such that is acyclic.