bluuebunny/crossref_metadata_2025 huggingface dataset:
An Integrated Computational and Experimental Approach to Gaining Selectivity for MMP‐2 within the Gelatinase Subfamily
Authors: Fabre Benjamin , Filipiak Kamila , Díaz Natalia , Zapico José María , Suárez Dimas , Ramos Ana , de Pascual‐Teresa Beatriz
Published: January 2014

Looking for water‐soluble inhibitors of matrix metalloproteinase‐2 (MMP‐2 or gelatinase A), we have previously reported compound 1, a potent MMP‐2 inhibitor with a promising selectivity over the structurally homologous MMP‐9 (gelatinase B). Here we report the results of Molecular Dynamics (MD) simulations for both gelatinases (MMP‐2 and MMP‐9), and for the corresponding MMP/1 complexes, in an attempt to shed light on the observed selectivity between the two enzymes. These studies indicated a higher plasticity of MMP‐2 at the S1′ pocket and suggested an induced‐fit effect at the “back door” of this pocket. On the basis of these observations, we designed 11 a–d to aid further discrimination between MMP‐2 and MMP‐9. Those compounds displayed notably lower inhibitory activities against MMP‐9; in particular, 11 b proved to be over 100 times more active against MMP‐2 than against MMP‐9. MD simulations of the MMP/11 b complexes and thermodynamic integration calculations provided structural insight and relative binding energies consistent with the experimentally observed activity data. These findings demonstrate that structural differences in the S1′ pocket bottom permit an improvement in selectivity in the inhibition of MMP‐2 over that of MMP‐9; this is of great relevance for future structure‐based drug design because MMP‐2 is a validated target for cancer therapy, whereas MMP‐9 plays both detrimental and protective roles in cancer. This study also supports the need to consider the dynamics of the S1′ pocket in order to achieve selectivity in the inhibition of MMPs.
Metal Ions in Life Sciences, Vol. 12: Metallomics and the Cell. Edited by Lucia Banci.
Authors: Krezel Artur
Published: January 2014

Springer, Dordrecht 2013, XXXVI+609 pp., hardcover, € 181.85.—ISBN 978‐94‐007‐5560‐4
NecroX‐5 suppresses sodium nitroprusside‐induced cardiac cell death through inhibition of JNK and caspase‐3 activation
Authors: Lee Sung Ryul , Lee Seon Joong , Kim Soon Ha , Ko Kyung Soo , Rhee Byoung Doo , Xu Zhelong , Kim Nari , Han Jin
Published: January 2014

Although sodium nitroprusside (SNP) is an effective hypotensive drug and is often used in pediatric intensive care units and to treat acute heart failure, clinical application of SNP is limited by its cardiotoxicity. NecroX‐5 (NX‐5) was recently developed and has the capacity to inhibit necrotic cell death. No current literature addresses whether NX‐5 suppresses SNP‐induced cell death or its mechanism of action. We have investigated the protective role of NX‐5 against SNP‐induced cell death in cardiomyocyte‐like H9c2 cells. SNP treatment induced severe cell death, possibly through phosphorylation of stress‐activated protein kinase/c‐Jun NH2‐terminal kinase (JNK) and activation of the apoptotic signaling pathway, including downregulation of Bcl‐2 and cleavage of caspase‐3. However, NX‐5 suppresses SNP‐induced cell death through inhibition of JNK activation and suppression of both downregulation of Bcl‐2 protein expression and caspase‐3 cleavage. These findings will provide insights and facilitate development of antidotes to SNP toxicity in cardiac cells.
Creation of Brønsted Acidity by Grafting Aluminum Isopropoxide on Silica under Controlled Conditions: Determination of the Number of Brønsted Sites and their Turnover Frequency for m‐Xylene Isomerization
Authors: Caillot Maxime , Chaumonnot Alexandra , Digne Mathieu , Van Bokhoven Jeroen A.
Published: January 2014

There is not a unique Brønsted acid site for aluminosilicates (ASAs). IR spectroscopy following CO adsorption proves the creation of Brønsted acid sites on Al/SiO2 ASAs, which are synthesized by the deposition of aluminum species on hydroxylated silica. These sites are active for ethanol dehydration and m‐xylene isomerization. Controlled deposition under anhydrous conditions optimizes the number of sites, whereas the presence of water leads to alumina agglomerates with no Brønsted acidity. The turnover frequency for m‐xylene isomerization (4.3×10−4 s−1 site−1 at 350 °C, atmospheric pressure, and 0.6 cm3 h−1 of m‐xylene) is approximately 3 times lower than that of the Brønsted acid sites of Si/Al2O3 and 75 times lower than that of an ultrastable Y‐type zeolite without extra‐framework aluminum.
Bismuth‐Based Pervoskite as a High‐Performance Cathode for Intermediate‐Temperature Solid‐Oxide Fuel Cells
Authors: Huang Shouguo , Gao Feng , Meng Zheng , Feng Shuangjiu , Sun Xiaohong , Li Yide , Wang Chunchang
Published: January 2014

A new bismuth‐based perovskite cathode material, Bi0.5Sr0.5Fe0.8Co0.2O3−δ (BiSFC), showing not only low area‐specific resistance but also a low thermal expansion coefficient, exhibits excellent electrochemical catalytic activity for the oxygen reduction reaction in the application of intermediate‐temperature solid‐oxide fuel cells (ITSOFCs). The high performance implies that BiSFC is a very promising cathode material for ITSOFCs.
First‐Principles Modeling of Electrochemical Water Oxidation on MnO:ZnO(001)
Authors: Kanan Dalal K. , Keith John A. , Carter Emily A.
Published: January 2014

The demand for renewable hydrogen derived from CO2‐neutral water‐splitting processes spurs efforts to develop new catalysts, including those inspired by nature. A first‐principles quantum mechanics (Kohn–Sham density functional theory + U) approach has been used to model electrocatalytic water oxidation on the visible‐light‐absorbing transition‐metal oxide alloy, MnO:ZnO; a material that can be considered a heterogeneous analogue to the photosystem II photocatalyst. Ab‐initio‐derived U values were used to correct self‐interaction errors in the highly correlated material. It has been confirmed that previously established scaling relationships between the binding energies of reaction intermediates are valid. The predicted electrochemical overpotential for water oxidation under experimentally relevant conditions (0.82 V versus the standard hydrogen electrode) is slightly higher than those values reported for manganese oxides and comparable to those previously calculated values for hematite photoanodes.
Phenothiazine‐Capped Gold Nanoparticles: Photochemically Assisted Synthesis and Application in Electrosensing of Phosphate Ions
Authors: Gupta Sandeep , Singh Akhilesh K. , Jain Ravish K. , Chandra Ramesh , Prakash Rajiv
Published: January 2014

We describe a green photochemical route for the synthesis of gold nanoparticles (AuNPs) using phenothiazine (PTZH) as a reductant as well as a stabilizer without any extra control (i.e. surfactant, pH, etc.). The synthesized AuNPs are characterized by using UV/Vis spectroscopy, cyclic voltammetry, and transmission electron microscopy. Furthermore, a possible mechanism for the formation of the AuNPs is proposed. This hybrid electrode material, derived from nanoscale gold particles capped with PTZH and its oxidation product, is explored for the development of a highly sensitive amperometric sensor for phosphate ions. The electrochemistry behind the electrocatalytic sensing of phosphate is attributed to the nano‐sized gold particles that are capped with PTZH and its oxidation product, which exhibit high electron‐transfer kinetics through the interaction of the hybrid PTZH–AuNPs with oxygen atoms of ${{\rm{PO}}_4^{3 - } }$. The modified electrode efficiently gives an electrochemical signature of phosphate ions at a potential of −0.336 V versus AgCl/Ag and shows a linear response toward phosphate sensing, with a sensitivity of 0.794 μA μM−1 and a limit of detection of 0.022 μm, at a signal‐to‐noise ratio of 3.
Simultaneous Electrochemical Detection of Silver and Molybdenum Nanoparticles
Authors: Goda Tatsuro , Ambrosi Adriano , Miyahara Yuji , Pumera Martin
Published: January 2014

Nanoparticles (NPs) and quantum dots (QDs) are of interest as redox tags in electrochemical biosensing. Simultaneous monitoring of the redox reactions of these tags with different redox potentials under mild conditions may allow the multiplex detection of target analytes in point‐of‐care applications. The multiplex detection of Ag and Mo NPs on a glassy carbon electrode is investigated under mild aqueous conditions (pH 7.2) by using differential pulse voltammetry. The separation in the oxidative peaks allows us to successfully quantify each component of the NPs at a time. The redox signals are proportional to the amount of each NP, with the dynamic ranges of 0.313 to 10 ng for Ag NP and 31.3 to 500 ng for Mo NP on the working electrode. The electrochemical features of these NPs meet the requirements of redox tags for multiplex sensing schemes, without the need for NP dissolution by using strong acid and base reagents.
The Development of Copper‐Catalyzed Aerobic Oxidative Coupling of H‐Tetrazoles with Boronic Acids and an Insight into the Reaction Mechanism
Authors: Liu Chao‐You , Li Yu , Ding Jin‐Ying , Dong De‐Wen , Han Fu‐She
Published: January 2014

The development of a highly efficient and practical protocol for the direct CN coupling of H‐tetrazole and boronic acid was presented. A careful and patient optimization of a variety of reaction parameters revealed that this conventionally challenge reaction could indeed proceed efficiently in a very simple system, that is, just by stirring the tetrazoles and boronic acids under oxygen in the presence of different CuI or CuII salts with only 5 mol % loading in DMSO at 100 °C. Most significantly, the reaction could proceed very smoothly in a regiospecific manner to afford the 2,5‐disubstituted tetrazoles in high to excellent yields. A mechanistic study revealed that both tetrazole and DMSO are crucial for the generation of catalytically active copper species in the reaction process in addition to their role as reactant and solvent, respectively. It is demonstrated that in the reaction cycle, the CuI catalyst could be oxidized to CuII by oxygen to form a [CuT2D] complex (T=tetrazole anion; D=DMSO) through an oxidative copper amination reaction. The CuII complex thus formed was confirmed to be the real catalytically active copper species. Namely, the CuII complex disproportionates to aryl CuIII and CuI in the presence of boronic acid. Facile elimination of the CuIII species delivers the CN‐coupled product. The results presented herein not only provide a reliable and efficient protocol for the synthesis of 2,5‐disubstituted tetrazoles, but most importantly, the mechanistic results would have broad implications for the de novo design and development of new methods for Cu‐catalyzed coupling reactions.
AgI Microplate Monocrystals with Polar {0001} Facets: Spontaneous Photocarrier Separation and Enhanced Photocatalytic Activity
Authors: Kuang Qin , Zheng Xiaoli , Yang Shihe
Published: January 2014

Elucidating the facet‐dependent photocatalytic activity of semiconductor photocatalysts is important in improving the overall efficiency of photocatalysis. Furthermore, combining facet control with selective deposition of oxidation and/or reduction cocatalysts on specific faces of semiconductor photocatalysts is potentially an effective strategy to synergistically optimize the functionality of photocatalysts. In the present study, high‐purity wurtzite‐type β‐AgI platelet microcrystals with polar {0001} facets were prepared by a facile polyvinylpyrrolidone‐assisted precipitation reaction. The polar‐faceted AgI microplates were used as archetypes to demonstrate preferential diametric migration (i.e., effective separation) of photogenerated electrons and holes along the c axis. Such vectorial electron–hole separation stems from the asymmetric surface structures, which give rise to distinct photoexcited reaction behaviors on the ±(0001) polar facets of wurtzite‐type semiconductors. Furthermore, on selective deposition of Ag and MnOx (1.5<x<2) cocatalysts on the reductive (0001) and oxidative (000$\bar 1$) facets, respectively, photocatalytic activity of the AgI microplates in degrading organic pollutants was dramatically enhanced thanks to the broad light‐absorption range, strong dye‐adsorption ability, and effective spatial separation of photocarriers.
Dipolarity versus Polarizability and Acidity versus Basicity of Ionic Liquids as a Function of Their Molecular Structures
Authors: Schade Alexander , Behme Nicole , Spange Stefan
Published: January 2014

The four empirical solvent polarity parameters according to the Catalán scale—solvent acidity (SA), solvent basicity (SB), solvent polarizability (SP), and solvent dipolarity (SdP)—of 64 ionic liquids (ILs) were determined by the solvatochromic method. The SA parameter was determined solely by using [FeII(1,10‐phenanthroline)2(CN)2] (Fe), the SB parameter by using the pair of structurally comparable dyes 3‐(4‐amino‐3‐methylphenyl)‐7‐phenylbenzo[1,2‐b:4,5‐b′]difuran‐2,6‐dione (ABF) and 3‐(4‐N,N‐dimethylaminophenyl)‐7‐phenylbenzo[1,2‐b:4,5‐b′]‐difuran‐2,6‐dione (DMe‐ABF), and the SP and SdP parameters by using the homomorphic pair of 4‐tert‐butyl‐2‐(dicyanomethylene)‐5‐[4‐(diethylamino)benzylidene]‐Δ3‐thiazoline (Th) and 2‐[4‐(N,N‐dimethylamino)benzylidene]malononitrile (BMN). The separation of SP and SdP for a set of 64 various ILs was performed for the first time. Correlation analyses of SP with physicochemical data related to ionization potentials of anions of ILs as well as with theoretical data show the correctness of the applied method. The found correlations of the Catalán parameters with each other and with the alkyl‐chain length of 1‐alkyl‐3‐methylimidazolium‐type ILs gives new information about interactions within ILs. An analytical comparison of the determined Catalán parameters with the established Kamlet–Taft parameters and the Gutmann acceptor and donor numbers is also presented.
Palladium‐Catalyzed One‐Pot Three‐ or Four‐Component Coupling of Aryl Iodides, Alkynes, and Amines through CN Bond Cleavage: Efficient Synthesis of Indole Derivatives
Authors: Hao Wei , Geng Weizhi , Zhang Wen‐Xiong , Xi Zhenfeng
Published: January 2014

An efficient synthesis of N‐substituted indole derivatives was realized by combining the Pd‐catalyzed one‐pot multicomponent coupling approach with cleavage of the C(sp3)N bonds. Three or four components of aryl iodides, alkynes, and amines were involved in this coupling process. The cyclopentadiene–phosphine ligand showed high efficiency. A variety of aryl iodides, including cyclic and acyclic tertiary amino aryl iodides, and substituted 1‐bromo‐2‐iodobenzene derivatives could be used. Both symmetric and unsymmetric alkynes substituted with alkyl, aryl, or trimethylsilyl groups could be applied. Cyclic secondary amines such as piperidine, morpholine, 4‐methylpiperidine, 1‐methylpiperazine, 2‐methylpiperidine, and acyclic amines including secondary and primary amines all showed good reactivity. Further application of the resulting indole derivatives was demonstrated by the synthesis of benzosilolo[2,3‐b]indole.
Highly Luminescent N‐Doped Carbon Quantum Dots as an Effective Multifunctional Fluorescence Sensing Platform
Authors: Qian Zhaosheng , Ma Juanjuan , Shan Xiaoyue , Feng Hui , Shao Linxiang , Chen Jianrong
Published: January 2014

The doping of carbon quantum dots with nitrogen provides a promising direction to improve fluorescence performance and broaden their applications in sensing systems. Herein we report a one‐pot solvothermal synthesis of N‐doped carbon quantum dots (NCQDs) and the synthesis of a series of NCQDs with different nitrogen contents. The as‐prepared NCQDs were compared with carbon quantum dots (CQDs); the introduction of nitrogen atoms largely increased the quantum yield of NCQDs and highest emission efficiency is up to 36.3 %. The fluorescence enhancement may originate from more polyaromatic structures induced by incorporated nitrogen atoms and protonation of nitrogen atoms on dots. It was found that NCQDs can act as a multifunctional fluorescence sensing platform because they can be used to detect pH values, AgI, and FeIII in aqueous solution. The fluorescence intensity of NCQDs is inversely proportional to pH values across a broad range from 5.0 to 13.5, which indicates that NCQDs can be devised as an effective pH indicator. Selective detection of AgI and FeIII was achieved based on their distinctive fluorescence influence because AgI can significantly enhance the fluorescence whereas FeIII can greatly quench the fluorescence. The quantitative determination of AgI can be accomplished with NCQDs by using the linear relationship between fluorescence intensity of NCQDs and concentration of AgI. The sensitive detection of H2O2 was developed by taking advantage of the distinct quenching ability of FeIII and FeII toward the fluorescence of NCQDs. Cellular toxicity test showed NCQDs still retain low toxicity to cells despite the introduction of a great deal of nitrogen atoms. Moreover, bioimaging experiments demonstrated that NCQDs have stronger resistance to photobleaching than CQDs and more excellent fluorescence labeling performance.
Enzymkinetische Untersuchungen mit Nahrungsergänzungsmitteln und moderner Medizindiagnostik
Authors: Heinzerling Peter , Schanze Sascha
Published: January 2014

Enzymkinetische Untersuchungen erfordern in der Regel einen hohen apparativen und analytischen Aufwand und führen in der Schule nicht immer zu optimalen Ergebnissen. In der Schulliteratur wird überwiegend mit Urease gearbeitet. Wir verwenden als Enzymquellen frei verkäufliche Nahrungsergänzungsmittel aus der Apotheke. Analytisch werden die Resultate mit einem Glucometer erfasst. Diese Alltagsgeräte liefern in fünf Sekunden fertige Resultate. Die Experimente waren auch mit Inhibitoren erfolgreich.
Novel Heterobimetallic Radiotheranostic: Preparation, Activity, and Biodistribution
Authors: Adriaenssens Louis , Liu Qiang , Chaux‐Picquet Fanny , Tasan Semra , Picquet Michel , Denat Franck , Le Gendre Pierre , Marques Fernanda , Fernandes Célia , Mendes Filipa , Gano Lurdes , Campello Maria Paula Cabral , Bodio Ewen
Published: January 2014

A novel RuII(arene) theranostic complex is presented. It is based on a 1,4,7,10‐tetraazacyclododecane‐1,4,7,10‐tetraacetic acid macrocycle bearing a triarylphosphine and can be tracked in vivo by using the γ emission of 153Sm atoms. Notably, the heteroditopic ligand can be selectively metalated with ruthenium at the phosphorus atom despite the presence of other functionalities that are prone to metal coordination. Subsequent labeling with radionuclides such as 153Sm can then be performed easily. The resulting heterobimetallic complex exhibits favorable solubility and stability properties in biologically relevant media. It also shows in vitro cytotoxicity in line with that expected for this type of metallodrug, and is nontoxic to the organism as a whole. As a proof of concept, initial studies in healthy mice were performed to obtain information about the uptake, biodistribution, and excretion of the radiolabeled complex.
Suprema of Chaos Processes and the Restricted Isometry Property
Authors: Krahmer Felix , Mendelson Shahar , Rauhut Holger
Published: January 2014

We present a new bound for suprema of a special type of chaos process indexed by a set of matrices, which is based on a chaining method. As applications we show significantly improved estimates for the restricted isometry constants of partial random circulant matrices and time‐frequency structured random matrices. In both cases the required condition on the number m of rows in terms of the sparsity s and the vector length n is m ≳ s log2 s log2 n. © 2014 Wiley Periodicals, Inc.
Reorientational Dynamics of Water Confined in Zeolites
Authors: Fogarty Aoife C. , Coudert François‐Xavier , Boutin Anne , Laage Damien
Published: January 2014

We present a detailed molecular‐dynamics study of water reorientation and hydrogen‐bond dynamics in a strong confinement situation, within the narrow pores of an all‐silica Linde type A (LTA) zeolite. Two water loadings of the zeolite are compared with the bulk case. Water dynamics are retarded in this extreme hydrophobic confinement and the slowdown is more pronounced at higher water loading. We show that water reorientation proceeds mainly by large‐amplitude angular jumps, whose mechanism is similar to that determined in the bulk. The slowdown upon hydrophobic confinement arises predominantly from an excluded‐volume effect on the large fraction of water molecules lying at the interface with the zeolite matrix, with an additional minor contribution coming from a structuring effect induced by the confinement.
1D and 2D Thiazole‐Based Copper(II) Coordination Polymers: Synthesis and Applications in Carbon Dioxide Capture
Authors: Rossin Andrea , Tuci Giulia , Giambastiani Giuliano , Peruzzini Maurizio
Published: January 2014

The reaction of different copper(II) salts with a class of thiazole‐based ligands under solvothermal conditions produces three crystalline 1D/2D coordination polymers: [Cu(κ‐N‐thiazole)4(SiF6)]∞ (1 (1D)), {Cu[μ‐(κ‐N:κ‐COO)‐L1]2⋅(H2O)}∞ (2 (2D); HL1=2‐aminothiazole‐5‐carboxylic acid), and {Cu[μ‐(κ‐N:κ‐COO)‐L2]2⋅1.5 (H2O)}∞ (3 (2D); HL2=thiazole‐5‐carboxylic acid). All the materials have been characterized through common solid‐state techniques: single‐crystal (XRD) and (variable‐temperature) powder X‐ray diffraction (PXRD), infrared spectroscopy (IR), thermogravimetric analysis combined with mass spectrometry (TGA‐MS), and BET surface area and pore‐size distribution measurements. Polymer 3 shows a porous structure made of squared channels formed by the ordered stacking of the planar sheets along the a crystallographic axis (inner surface area equal to 15 m2 g−1, as inferred from N2 adsorption at T=77 K on the pre‐activated form), and it has been exploited for CO2 physisorption at ambient temperature (T=303 K) and pressure (p max.=920 torr). A remarkable CO2 uptake equal to 9.0 wt % was recorded under these mild conditions, thereby making the material promising for carbon dioxide capture in post‐combustion flue gas, in which the key factor for a successful performance is the high chemical selectivity for CO2 over N2.
Resilience of Zostera muelleri seagrass to small‐scale disturbances: the relative importance of asexual versus sexual recovery
Authors: Macreadie Peter I. , York Paul H. , Sherman Craig D.H.
Published: January 2014

Resilience is the ability of an ecosystem to recover from disturbance without loss of essential function. Seagrass ecosystems are key marine and estuarine habitats that are under threat from a variety of natural and anthropogenic disturbances. The ability of these ecosystems to recovery from disturbance will to a large extent depend on the internsity and scale of the disturbance, and the relative importance of sexual versus asexual reproduction within populations. Here, we investigated the resilience of Zostera muelleri seagrass (Syn. Zostera capricorni) to small‐scale disturbances at four locations in Lake Macquarie – Australia's largest coastal lake – and monitored recovery over a 65‐week period. Resilience of Z. muelleri varied significantly with disturbance intensity; Z. muelleri recovered rapidly (within 2 weeks) from low‐intensity disturbance (shoot loss), and rates of recovery appeared related to initial shoot length. Recovery via rhizome encroachment (asexual regeneration) from high‐intensity disturbance (loss of entire plant) varied among locations, ranging from 18‐35 weeks, whereas the ability to recover was apparently lost (at least within the time frame of this study) when recovery depended on sexual regeneration, suggesting that seeds do not provide a mechanism of recovery against intense small‐scale disturbances. The lack of sexual recruits into disturbed sites is surprising as our initial surveys of genotypic diversity (using nine polymorphic microsatellite loci) at these location indicate that populations are maintained by a mix of sexual and asexual reproduction (genotypic diversity [R] varied from 0.24 to 0.44), and populations consisted of a mosaic of genotypes with on average 3.6 unique multilocus genotypes per 300 mm diameter plot. We therefore conclude that Z. muelleri populations within Lake Macquarie rely on clonal growth to recover from small‐scale disturbances and that ongoing sexual recruitment by seeds into established seagrass beds (as opposed to bare areas arising from disturbance) must be the mechanism responsible for maintaining the observed mixed genetic composition of Z. muelleri seagrass meadows.
A Propeller‐Shaped, Triazine‐Linked Porphyrin Triad as Efficient Sensitizer for Dye‐Sensitized Solar Cells
Authors: Zervaki Galateia E. , Papastamatakis Evangelos , Angaridis Panagiotis A. , Nikolaou Vasilis , Singh Manjeet , Kurchania Rajnish , Kitsopoulos Theophanis N. , Sharma Ganesh D. , Coutsolelos Athanassios G.
Published: January 2014

A propeller‐shaped, triazine‐linked, unsymmetrical porphyrin triad – consisting of two zinc‐metallated porphyrin units and one free‐base porphyrin unit that is functionalized by a carboxylic acid – has been synthesized by stepwise amination reactions of cyanuric chloride. Photophysical, electrochemical, and DFT studies of the triad revealed no significant electronic interactions between the porphyrin units in the triad ground state but frontier orbital energy levels suitable for use as sensitizer in dye‐sensitized solar cells (DSSCs). Furthermore, the triad can be described as a 2D–π–A system (D: donor, A: acceptor) that has the potential to promote electron transfer and injection into the TiO2 electrode. Solar cells sensitized by the triad were fabricated with two different TiO2 photoanodes, one processed by the paste‐coating (PC) method and the other by the electrophoretic deposition (EPD) method. They were found to exhibit power conversion efficiencies (PCEs) of 3.80 and 4.91 %, respectively. The higher PCE value of the latter is attributed to its larger dye loading, as well as to its enhanced short‐circuit current (Jsc) and higher open‐circuit voltage (Voc) and fill factor (FF) values. In addition, differences in the surface morphology between the two different TiO2 photoanodes result in different electron‐transport kinetics. Electrochemical impedance spectra (EIS) demonstrated that the solar cell with the EPD‐processed photoanode exhibits a shorter electron‐transport time (τd), a longer electron lifetime, and higher charge‐recombination resistance (Rct). The PCE of the latter solar cell was further improved up to 5.56 % by incorporating chenodeoxycholic acid in the dye solution as co‐sensitizer.
One‐Dimensional Structure of an Aluminum Coordination Compound
Authors: Yang Zhi , Li Kai , Ma Xiaoli , Roesky Herbert W. , Hao Pengfei , Zhong Mingdong
Published: January 2014

The reaction of trimethylaluminum with a salen {salenH2 = [N,N′‐bis(salicylidene)ethylenediamine]} ligand in toluene afforded the complex [Me2AlOC6H4CH=NCH2–]n. It shows a one‐dimensional structure in the crystal state with pentacoordinate aluminum. This complex was characterized by 1H and 13C NMR spectroscopy, IR spectroscopy, single‐crystal X‐ray structure, and elemental analysis.
Evaluation of mesoporous silicas functionalized with C18 groups as stationary phases for the solid‐phase extraction of steroid hormones in milk
Authors: Pérez‐Fernández Virginia , Morante‐Zarcero Sonia , Pérez‐Quintanilla Damián , García María Ángeles , Marina María Luisa , Alonso Isabel Sierra
Published: January 2014

In this work, two mesoporous silicas functionalized with C18 groups (SM‐C18 and SBA‐15‐C18) have been synthesized for their evaluation as stationary phases in SPE for the extraction and preconcentration of seven steroid hormones (estrone, estradiol, estriol, ethinyl estradiol, diethylstilbestrol, testosterone, and progesterone ) from milk. The characterization of both materials by diverse techniques such as transmission electron microscopy, SEM, thermogravimetric analysis, X‐ray diffraction, and adsorption–desorption isotherms showed that the mesoporous silicas had a high surface area, high pore volume, and a homogeneous distribution of the pores and that both silicas presented a similar degree of functionalization. An analytical methodology for the simultaneous separation of the seven selected steroids by HPLC‐DAD was developed. Both silicas were evaluated as stationary phases in SPE for the extraction of the steroid hormones from milk. This HPLC‐DAD method was applied to the analysis of all extracts obtained in the SPE experiments, showing that from the two synthesized mesoporus silicas, SBA‐15‐C18 silica enabled the extraction of the seven compounds with recoveries between 88 and 108% for all except for estriol, for which a recovery of 62% was obtained. The analytical characteristics of this methodology were evaluated, showing good precision and linearity (R2 > 0.994) for all analytes. The comparison of the results obtained with this silica and those obtained with commercial C18 particles and with some other commercial cartridges usually employed in the extraction of steroids showed that SBA‐15‐C18 silica was able to extract the seven steroids with higher recovery values.
Cell cultures in uterine leiomyomas: Rapid disappearance of cells carrying MED12 mutations
Authors: Nadine Markowski Dominique , Tadayyon Mahboobeh , Bartnitzke Sabine , Belge Gazanfer , Maria Helmke Burkhard , Bullerdiek Jörn
Published: January 2014

Uterine leiomyomas (UL) are the most frequent symptomatic human tumors. Nevertheless, their molecular pathogenesis is not yet fully understood. To learn more about the biology of these common neoplasms and their response to treatment, cell cultures derived from UL are a frequently used model system, but until recently appropriate genetic markers confirming their origin from the tumor cell population were lacking for most UL, i.e., those not displaying karyotypic abnormalities. The identification of MED12 mutations in the majority of UL makes it possible to trace the tumor cell population during in vitro passaging in the absence of cytogenetic abnormalities. The present study is addressing the in vitro survival of cells carrying MED12 mutations and its association with karyotypic alterations. The results challenge numerous in vitro studies into the biology and behavior of leiomyomas. Cells of one genetic subtype of UL, i.e., those with rearrangements of the high mobility AT‐hook 2 protein gene (HMGA2), seem to be able to proliferate in vitro for many passages whereas tumor cells from the much more frequent MED12‐mutated lesions barely survive even the first passages. Apparently, for the most frequent type of human UL no good in vitro model seems to exist because cells do not survive culturing. On the other hand, this inability may point to an Achilles' heel of this type of UL. © 2014 Wiley Periodicals, Inc.
ITPA genotype protects against anemia during peginterferon and ribavirin therapy but does not influence virological response
Authors: Holmes Jacinta A. , Roberts Stuart K. , Ali Rachel J. , Dore Gregory J. , Sievert William , McCaughan Geoffrey W. , Crawford Darrell H. , Cheng Wendy S. , Weltman Martin D. , Bonanzinga Sara , Visvanathan Kumar , Sundararajan Vijaya , Desmond Paul V. , Bowden Scott D. , Matthews Gail V. , Thompson Alexander J.
Published: January 2014

On-treatment anemia is associated with higher sustained virological response (SVR) rates during peginterferon plus ribavirin (RBV) therapy. Inosine triphosphatase (ITPA) variants causing ITPase deficiency have been shown to protect against RBV-induced anemia. However, ITPase activity has not been associated with SVR. To study this discrepancy, we examined the relationships between ITPase activity, on-treatment anemia, SVR, and RBV levels in hepatitis C virus genotype 1 (HCV-1) patients from the CHARIOT study. ITPA genotype (rs7270101, rs1127354) was used to define ITPase activity in 546 patients. Plasma RBV levels were measured using high-performance liquid chromatography (HPLC). Relationships between ITPase activity, on-treatment hemoglobin (Hb) levels, RBV levels, and SVR were tested using regression modeling, survival analysis, and locally weighted scatterplot smoothing (LOWESS) plot analysis. Hb decline was independently associated with SVR (P < 0.0001). ITPase deficiency was present in 35%. ITPase deficiency strongly protected against Hb decline (P < 0.0001), but was not associated with SVR (P = 0.28). The probability of SVR increased with lower nadir Hb for both wild-type and deficient ITPase activity, but the association curve shifted to describe a parallel relationship at higher Hb levels in patients with ITPase deficiency. In a subset (n = 203), we tested the hypothesis that the association between Hb decline and SVR reflected RBV levels rather than actual Hb level. RBV levels were associated with on-treatment Hb decline and SVR, but not ITPase activity. In regression models, adjustment for RBV levels attenuated the association between Hb decline and SVR. Conclusion: ITPase deficiency protects against RBV-induced anemia, but is not associated with SVR. Our data suggest that the relationship between Hb decline and SVR is not mechanistic, but is linked to RBV levels. (Hepatology 2014;59:2152–2160)
Systems biology for hepatologists
Authors: Mato José M. , Martínez-Chantar Luz M. , Lu Shelly C.
Published: January 2014

Medicine is expected to benefit from combining usual cellular and molecular studies with high-throughput methods (genomics, transcriptomics, proteomics, and metabolomics). These methods, collectively known as omics, permit the determination of thousands of molecules (variations within genes, RNAs, proteins, metabolites) within a tissue, cell, or biological fluid. The use of these methods is very demanding in terms of the design of the study, acquisition, storage, analysis, and interpretation of the data. When carried out properly, these studies can reveal new etiological pathways, help to identify patients at risk for disease, and predict the response to specific treatments. Here we review these omics methods and mention several applications in hepatology research. (Hepatology 2014;60:736–743)
Alpha-1-antitrypsin inhibits acute liver failure in mice
Authors: Jedicke Nils , Struever Nina , Aggrawal Nupur , Welte Tobias , Manns Michael P. , Malek Nisar P. , Zender Lars , Janciauskiene Sabina , Wuestefeld Torsten
Published: January 2014

Acute liver failure remains a critical clinical condition, with high mortality rates, and increased apoptosis of hepatocytes represents a key event in the cause of liver failure. Alpha-1-antitrypsin (AAT) is synthesized and secreted mainly by hepatocytes, and plasma purified AAT is used for augmentation therapy in patients with AAT deficiency. Because AAT therapy exerts antiinflammatory and immune modulatory activities in various experimental models, and it was recently suggested that AAT exerts antiapoptotic activities, we aimed to explore whether administration of AAT may represent a therapeutic strategy to treat acute liver failure in mice. Well-established preclinical models of acute liver failure such as the Jo2 FAS/CD95 activating model and models of acetaminophen and α-amanitin poisoning were used. Therapeutic effects of AAT were evaluated by monitoring animal survival, histopathological changes, measurement of caspase activity, and serum cytokine levels. Systemic treatment with AAT significantly decreased Jo2-induced liver cell apoptosis and prolonged survival of mice. Native and oxidized (lacking elastase inhibitory activity) forms of AAT were equally effective in preventing acute liver injury and showed direct inhibition of active caspase-3 and −8 in liver homogenates and in a cell-free system in vitro. Concomitantly, mice treated with AAT showed significantly lower serum levels of tumor necrosis factor alpha (TNF-α), which also paralleled the reduced activity of ADAM17 (TACE). Noticeably, the increased survival and a reduction of apoptotic hepatocytes were also observed in the α-amanitin and acetaminophen-induced liver injury mouse models. Conclusion: Our data suggest that systemic administration of AAT can be a promising therapy to treat acute liver failure and clinical studies to explore this treatment in humans should be initiated. (Hepatology 2014;59:2299–2308)
Human temporal lobe epilepsy analyses by tissue proteomics
Authors: Mériaux Céline , Franck Julien , Park Dan Bi , Quanico Jusal , Kim Young Hye , Chung Chun Kee , Park Young Mok , Steinbusch Harry , Salzet Michel , Fournier Isabelle
Published: January 2014

Although there are many types of epilepsy, temporal lobe epilepsy (TLE) is probably in humans the most common and most often studied. TLE represents 40% of the total epilepsy form of the disease and is difficult to treat. Despite a wealth of descriptive data obtained from the disease history of patients, the EEG recording, imaging techniques, and histological studies, the epileptogenic process remains poorly understood. However, it is unlikely that a single factor or a single mechanism can cause many changes associated with this neuropathological phenomenon. MALDI mass spectrometry imaging (MSI) coupled to protein identification, because of its ability to study a wide range of molecules, appears to be suitable for the preparation of molecular profiles in TLE. Seven neuropeptides have been have been identified in Dental gyrus regions of the hippocampus in relation with TLE pathology. Shot‐gun studies taking into account gender influence have been performed. Tissue microextraction from control (10) toward 10 TLE patients have been analyzed after trypsin digestion followed by separation on nanoLC coupled to LTQ orbitrap. From the shot‐gun analyses, results confirmed the presence of specific neuropeptides precursors and receptors in TLE patients as well as proteins involved in axons regeneration including neurotrophins, ECM proteins, cell surface proteins, membrane proteins, G‐proteins, cytoskeleton proteins and tumor suppressors. Among the tumor suppressors identified, the Leucine‐rich glioma inactivated 1 (LGI1) protein was found. LGI1 gene recently been demonstrated being implicated in heritability of TLE. We have also demonstrate the presence a complete profile of tumor suppressors in TLE patients, 7 have been identified. Refining this analysis taken into account the gender influence in both control and in TLE reflected the presence of specific proteins between male and female and thus mechanisms in pathology development could be completely different. © 2014 Wiley Periodicals, Inc.
The role of the ventral dentate gyrus in olfactory pattern separation
Authors: Weeden Christy S. S. , Hu Nathan J. , Ho Liana U. N. , Kesner Raymond P.
Published: January 2014

Dorsoventral lesion studies of the hippocampus have indicated that the dorsal axis of the hippocampus is important for spatial processing and the ventral axis of the hippocampus is important for olfactory learning and memory and anxiety. There is some evidence to suggest that the ventral CA3 and ventral CA1 conduct parallel processes for pattern completion and temporal processing, respectively. Studies have indicated that the dorsal dentate gyrus (DG) is importantly involved in processes reflecting underlying pattern separation activity for spatial information. However, the ventral DG is less understood. The current study investigated the less‐understood role of the ventral DG in olfactory pattern separation. A series of odor stimuli that varied on only one level, number of carbon chains (methyl groups), was used in a matching‐to‐sample paradigm in order to investigate ventral DG involvement in working memory for similar and less similar odors. Rats with ventral DG lesions were impaired at delays of 60 sec, but not at delays of 15 sec. A memory‐based pattern separation effect was observed performance was poorest with only one carbon chain separation between trial odors and was highest for trials with four separations. The present study indicates that the ventral DG plays an important role in olfactory learning and memory processes for highly similar odors. The results also indicate a role for the ventral DG in pattern separation for odor information, which may have further implications for parallel processing across the dorsoventral axis for the DG in spatial (dorsal) and olfactory (ventral) pattern separation. © 2014 Wiley Periodicals, Inc.
Reconsidering Boundaries: Human Resource Management in a Networked World
Authors: Swart Juani , Kinnie Nicholas
Published: January 2014

In the twenty‐first century, work activities tend to span organizational boundaries and take place in projects or networks. This cross‐boundary working has major implications for current HRM models that are more suited to an industrial economy, which assumes a single employer and where work is carried out within a set of clearly defined boundaries. We draw on a decade of empirical research in cross‐boundary contexts to identify: (1) three types of networks (interactive, interwoven, and integrated) that vary according to their boundary properties, the focus of the work activity, and the prominent identification; (2) the particular structural, relational, and knowledge‐based tensions (Phelps, Heidl, & Wadhwa, 2012) that are inherent in each networked context; and (3) three HRM models (buffering, borrowing, and balancing) that are appropriate to sustain networked working in these contexts. The main contribution of the article is the identification of HRM models in networked contexts. © 2014 Wiley Periodicals, Inc.
Acceptance and Commitment Therapy Versus Cognitive Behavioral Therapy in the Treatment of Substance Use Disorder With Incarcerated Women
Authors: Lanza Patricia Villagrá , García Paula Fernández , Lamelas Filomena Rodríguez , González‐Menéndez Ana
Published: January 2014

Objectives

This randomized controlled study compared acceptance and commitment therapy (ACT), cognitive‐behavioral therapy (CBT), and a control group.

Method

The participants were 50 incarcerated women diagnosed with current substance use disorder. Two psychologists carried out pre‐ and posttreatment assessment and a 6‐month follow‐up assessment using the following instruments: Anxiety Sensitivity Index, Addiction Severity Index‐6, Mini International Neuropsychiatric Interview, and Acceptance and Action Questionnaire.

Results

The study shows that the women who received treatment benefited differentially from the interventions. At posttreatment, CBT was more effective than ACT in reducing anxiety sensitivity; however, at follow‐up, ACT was more effective than CBT in reducing drug use (43.8 vs. 26.7%, respectively) and improving mental health (26.4% vs. 19.4%, respectively).

Conclusion

ACT may be an alternative to CBT for treatment of drug abuse and associated mental disorders. In fact, at long‐term, ACT may be more appropriate than CBT for incarcerated women who present serious problems.
Adaptive Responses of Mitochondria to Mild Copper Deprivation Involve Changes in Morphology, OXPHOS Remodeling and Bioenergetics
Authors: Ruiz Lina María , Jensen Erik L. , Bustos Rodrigo I. , Argüelloa Graciela , Gutierrez‐Garcia Ricardo , González Mauricio , Hernández Claudia , Paredes Rodolfo , Simon Felipe , Riedel Claudia , Ferrick David , Elorza Alvaro A.
Published: January 2014

Copper is an essential cofactor of complex IV of the electron transfer chain, and it is directly involved in the generation of mitochondrial membrane potential. Its deficiency induces the formation of ROS, large mitochondria and anemia. Thus, there is a connection between copper metabolism and bioenergetics, mitochondrial dynamics and erythropoiesis. Copper depletion might end in cellular apoptosis or necrosis. However, before entering into those irreversible processes, mitochondria may execute a series of adaptive responses. Mitochondrial adaptive responses (MAR) may involve multiple and diverse mechanisms for preserving cell life, such as mitochondrial dynamics, OXPHOS remodeling and bioenergetics output. In this study, a mild copper deficiency was produced in an animal model through intraperitoneal injections of bathocuproine disulfonate in order to study the MAR. Under these conditions, a new type of mitochondrial morphology was discovered in the liver. Termed the “butternut squash” mitochondria, it coexisted with normal and swollen mitochondria. Western blot analyses of mitochondrial dynamics proteins showed an up‐regulation of MFN‐2 and OPA1 fusion proteins. Furthermore, isolated liver mitochondria displayed OXPHOS remodeling through a decrease in supercomplex activity with a concomitant increase at an individual level of complexes I and IV, higher respiratory rates at complex I and II levels, higher oligomycin‐insensitive respiration, and lower respiratory control ratio values when compared to the control group. As expected, total ATP and ATP/ADP values were not significantly different, since animal's health was not compromised. As a whole, these results describe a compensatory and adaptive response of metabolism and bioenergetics under copper deprivation. J. Cell. Physiol. 229: 607–619, 2014. © 2013 Wiley Periodicals, Inc.
Functional Role of Connexins and Pannexins in the Interaction Between Vascular and Nervous System
Authors: Gaete Pablo S. , Lillo Mauricio A. , Figueroa Xavier F.
Published: January 2014

The microvascular network of the microcirculation works in tight communication with surrounding tissues to control blood supply and exchange of solutes. In cerebral circulation, microvascular endothelial cells constitute a selective permeability barrier that controls the environment of parenchymal brain tissue, which is known as the blood–brain barrier (BBB). Connexin‐ and pannexin‐formed channels (gap junctions and hemichannels) play a central role in the coordination of endothelial and smooth muscle cell function and connexin‐mediated signaling in endothelial cells is essential in the regulation of BBB permeability. Likewise, gap junction communication between astrocyte end‐feet also contributes to maintain the BBB integrity, but the participation of hemichannels in this process cannot be discarded. Sympathetic and sensory perivascular nerves are also involved in the control and coordination of vascular function through the release of vasoconstrictor or vasodilator signals and by the regulation of gap junction communication in the vessel wall. Conversely, ATP release through pannexin‐1‐formed channels mediates the α1‐adrenergic signaling. Furthermore, here we show that capsaicin‐induced CGRP release from mesenteric perivascular sensory nerves induces pannexin‐1‐formed channel opening, which in turn leads to reduction of pannexin‐1 and endothelial nitric oxide synthase (eNOS) expression along the time. Interestingly, blockade of CGRP receptors with CGRP8–37 increased eNOS expression by ∼5‐fold, suggesting that capsaicin‐sensitive sensory nerves are involved in the control of key signaling proteins for vascular function. In this review, we discuss the importance of connexin‐based channels in the control of BBB integrity and the functional interaction of vascular connexins and pannexins with the peripheral nervous system. J. Cell. Physiol. 229: 1336–1345, 2014. © 2014 Wiley Periodicals, Inc.