bluuebunny/crossref_metadata_2025 huggingface dataset:
Possibility of application of cytochrome P450 to bioremediation of dioxins
Authors: Sakaki Toshiyuki , Yamamoto Keiko , Ikushiro Shinichi
Published: January 2013

Dioxins, including polychlorinated dibenzo‐p‐dioxins (PCDDs), dibenzofurans, and coplanar polychlorinated biphenyls, are known to be metabolized by enzymes such as cytochrome (CYP) P450, angular dioxygenase, lignin peroxidase, and dehalogenase. It is noted that all of these enzymes have metal ions in their active centers, and the enzyme systems except for peroxidase each have a distinct electron transport chain. Among these enzyme systems, we have focused on cytochrome P450‐dependent metabolism of dioxins from the viewpoint of practical use for bioremediation. Mammalian and fungal cytochromes P450 showed remarkable activity toward low‐chlorinated PCDDs. In particular, mammalian cytochromes P450 belonging to the CYP1 family showed high activity. Rat CYP1A1 showed high activity toward 2,3,7‐trichloro‐dibenzo‐p‐dioxin but no detectable activity for 2,3,7,8‐tetrachloro‐dibenzo‐p‐dioxin (2,3,7,8‐TCDD). On the basis of these results, we assumed that enlarging the space of the substrate‐binding pocket of rat CYP1A1 might generate TCDD‐metabolizing enzyme. Large‐sized amino acids located at putative substrate‐recognition sites and F‐G loop were substituted for alanine by site‐directed mutagenesis. Finally, we successfully generated 2,3,7,8‐TCDD–metabolizing enzyme by site‐directed mutagenesis of rat CYP1A1. We hope that recombinant microorganisms harboring genetically engineered cytochrome P450 will be used for bioremediation of soil contaminated with PCDDs, polychlorinated dibenzofurans, and coplanar polychlorinated biphenyls in the future.
Another Look at the (Im‐)Precision of Individual Risk Estimates Made Using Actuarial Risk Assessment Instruments
Authors: Hart Stephen D. , Cooke David J.
Published: January 2013

We investigated the precision of individual risk estimates made using actuarial risk assessment instruments (ARAIs) by discussing some major conceptual issues and then illustrating them by analyzing new data. We used a standard multivariate statistical procedure, logistic regression, to create a new ARAI based on data from a follow‐up study of 90 adult male sex offenders. We indexed predictive precision at the group level using confidence intervals for group mean probability estimates, and at the individual level using prediction intervals for individual probability estimates. Consistent with past research, ARAI scores were moderately and significantly predictive of failure in the aggregate, but group probability estimates had substantial margins of error and individual probability estimates had very large margins of error. We conclude that, without major advances in our understanding of the causes of violence, ARAIs cannot be used to estimate the specific probability or absolute likelihood of future violence with any reasonable degree of precision or certainty. The implications for conducting violence risk assessments in forensic mental health are discussed. Copyright © 2013 John Wiley & Sons, Ltd.
Phospho‐Ser383‐Elk‐1 is localized to the mitotic spindles during cell cycle and interacts with mitotic kinase Aurora‐A
Authors: Demir Ozlem , Kurnaz Isil Aksan
Published: January 2013

Elk‐1 is a member of the E‐twenty‐six (ETS) domain superfamily of transcription factors and has been traditionally associated with mitogen‐induced immediate early gene transcription upon phosphorylation by mitogen activated protein kinases (ERK/MAPK). Elk‐1 is not only upregulated but also phosphorylated in brain tumour cells. However, in this study, we show for the first time that S383‐phosphorylated Elk‐1 (P‐S383‐Elk‐1) is associated with mitotic spindle poles from metaphase through telophase and relocates to the spindle midbody during cytokinesis, while Thr417Ala mutation is associated with DNA throughout mitosis. Serine 383 phosphorylation appears to be important for polar localization of Elk‐1, since exogenous protein including serine‐to‐alanine mutation was seen to be distributed throughout the spindle fibres. We further show that Elk‐1 interacts with the cell cycle kinase Aurora‐A, and when Aurora inhibitors are used, P‐S383‐Elk‐1 fails to localize to the poles and remains associated with DNA. Apart from one transcriptional repressor molecule, Kaiso, this is the first time a transactivator was shown to possess such mitotic localization and interaction. The functional significance and detailed mechanism of this cell cycle–related localization of Elk‐1 are yet to be determined. Copyright © 2013 John Wiley & Sons, Ltd.
De Novo Biosynthesis of Sexual Pheromone in the Labial Gland of Bumblebee Males
Authors: Žáček Petr , Prchalová‐Horňáková Darina , Tykva Richard , Kindl Jiří , Vogel Heiko , Svatoš Aleš , Pichová Iva , Valterová Irena
Published: January 2013

De novo biosynthesis of male sex pheromone from two bumblebee species (Bombus terrestrisandBombus lucorum) was studied by using in vitro incubations of labial glands (LGs) with radioactive [1,2‐14C]acetate and deuterated [D3]acetate. The labeled substrate was incorporated into several types of compounds, such as terpenic alcohols, fatty acids, esters, and hydrocarbons. A similar incubation of [1,2‐14C]acetate with fat bodies (FB) led to the formation of fatty acids, triacylglycerols (TAG), and hydrocarbons. To support the results from in vitro incubations, PCR analysis of fatty acid synthase (FAS) transcripts in LG and FB was performed. Relative quantification of FAS transcription levels revealed that the abundance of mRNA from the FAS gene is a function of the age ofB. terrestrismales. A comparison of the relative FAS mRNA gene transcription level in FB and LGs ofB. terrestrisandB. lucorummales proved that high biosynthetic activity takes place in the LGs of both species. Together, these results indicate that pheromone components are synthesized de novo in the LG.
New Structural Motif for Carboxylic Acid Perhydrolases
Authors: Yin DeLu (Tyler) , Purpero Vince M. , Fujii Ryota , Jing Qing , Kazlauskas Romas J.
Published: January 2013

Some serine hydrolases also catalyze a promiscuous reaction— reversible perhydrolysis of carboxylic acids to make peroxycarboxylic acids. Five X‐ray crystal structures of these carboxylic acid perhydrolases show a proline in the oxyanion loop. Here, we test whether this proline is essential for high perhydrolysis activity using Pseudomonas fluorescens esterase (PFE). The L29P variant of this esterase catalyzes perhydrolysis 43‐fold faster (kcat comparison) than the wild type. Surprisingly, saturation mutagenesis at the 29 position of PFE identified six other amino acid substitutions that increase perhydrolysis of acetic acid at least fourfold over the wild type. The best variant, L29I PFE, catalyzed perhydrolysis 83‐times faster (kcat comparison) than wild‐type PFE and twice as fast as L29P PFE. Despite the different amino acid in the oxyanion loop, L29I PFE shows a similar selectivity for hydrogen peroxide over water as L29P PFE (β0=170 vs. 160 M−1), and a similar fast formation of acetyl‐enzyme (140 vs. 62 U mg−1). X‐ray crystal structures of L29I PFE with and without bound acetate show an unusual mixture of two different oxyanion loop conformations. The type II β‐turn conformation resembles the wild‐type structure and is unlikely to increase perhydrolysis, but the type I β‐turn conformation creates a binding site for a second acetate. Modeling suggests that a previously proposed mechanism for L29P PFE can be extended to include L29I PFE, so that an acetate accepts a hydrogen bond to promote faster formation of the acetyl‐enzyme.
Palladium‐ and Nickel‐Catalyzed Alkenylation of Enolates
Authors: Ankner Tobias , Cosner Casey C. , Helquist Paul
Published: January 2013

Transition‐metal‐catalyzed alkenylation of enolates provides a direct method to synthesize broadly useful β,γ‐unsaturated carbonyl compounds from the corresponding carbonyl compound and alkenyl halides. Despite being reported in the early seventies, this reaction class saw little development for many years. In the past decade, however, efforts to develop this reaction further have increased considerably, and many research groups have reported efficient coupling protocols, including enantioselective versions. These reactions most commonly employ palladium catalysts, but there are also some important reports using nickel. There are many examples of this powerful transformation being used in the synthesis of complex natural products.
“Clickable” Vitamin B12 Derivative
Authors: Chromiński Mikołaj , Gryko Dorota
Published: January 2013

A “clickable” vitamin B12 derivative possessing the azide functionality at the 5′‐position was synthesized by means of a two‐step procedure on the gram scale. The reaction of cobalamin with mesyl chloride (MsCl) afforded the 5′‐OMs derivative, which was subsequently transformed to the desired 5′‐azide, the structure of which was confirmed using X‐ray analysis. It proved to be reactive in the azide–alkyne 1,3‐dipolar cycloaddition reaction to give substituted triazoles in high yields. A study of the reaction conditions and the scope of the process are reported.
Three‐Dimensional MOF‐Type Architectures with Tetravalent Uranium Hexanuclear Motifs (U6O8)
Authors: Falaise Clément , Volkringer Christophe , Vigier Jean‐François , Henry Natacha , Beaurain Arnaud , Loiseau Thierry
Published: January 2013

Four metal–organic frameworks (MOF) with tetravalent uranium have been solvothermally synthesized by treating UCl4 with rigid dicarboxylate linkers in N,N‐dimethylfomamide (DMF). The use of the ditopic ligands 4,4′‐biphenyldicarboxylate (1), 2,6‐naphthalenedicarboxylate (2), terephthalate (3), and fumarate (4) resulted in the formation of three‐dimensional networks based on the hexanuclear uranium‐centered motif [U6O4(OH)4(H2O)6]. This motif corresponds to an octahedral configuration of uranium nodes and is also known for thorium in crystalline solids. The atomic arrangement of this specific building unit with organic linkers is similar to that found in the zirconium‐based porous compounds of the UiO‐66/67 series. The structure of [U6O4(OH)4(H2O)6(L)6]⋅X (L=dicarboxylate ligand; X=DMF) shows the inorganic hexamers connected in a face‐centered cubic manner through the ditopic linkers to build up a three‐dimensional framework that delimits octahedral (from 5.4 Å for 4 up to 14.0 Å for 1) and tetrahedral cavities. The four compounds have been characterized by using single‐crystal X‐ray diffraction analysis (or powder diffraction analysis for 4). The tetravalent state of uranium has been examined by using XPS and solid‐state UV/Vis analyses. The measurement of the Brunauer–Emmett–Teller surface area indicated very low values (Langmuir <300 m2 g−1 for 1, <7 m2 g−1 for 2–4) and showed that the structures are quite unstable upon removal of the encapsulated DMF solvent.
Synthesis of Carbohydrate‐Functionalised Sequence‐Defined Oligo(amidoamine)s by Photochemical ThiolEne Coupling in a Continuous Flow Reactor
Authors: Wojcik Felix , O'Brien Alexander G. , Götze Sebastian , Seeberger Peter H. , Hartmann Laura
Published: January 2013

Poly/oligo(amidoamine)s (PAAs) have recently been recognised for their potential as well‐defined scaffolds for multiple carbohydrate presentation and as multivalent ligands. Herein, we report two complimentary strategies for the preparation of such sequence‐defined carbohydrate‐functionalised PAAs that use photochemical thiolene coupling (TEC) as an alternative to the established azide–alkyne cycloaddition (“click”) reaction. In the first approach, PAAs that contained multiple olefins were synthesised on a solid support from a new building block and subsequent conjugation with unprotected thio‐carbohydrates. Alternatively, a pre‐functionalised building block was prepared by using TEC and assembled on a solid support to provide a carbohydrate‐functionalised PAA. Both methods rely on the use of a continuous flow photoreactor for the TEC reactions. This system is highly efficient, owing to its short path length, and requires no additional radical initiator. Performing the reactions at 254 nm in Teflon AF‐2400 tubing provides a highly efficient TEC procedure for carbohydrate conjugation, as demonstrated in the reactions of O‐allyl glycosides with thiols. This method allowed the complete functionalisation of all of the reactive sites on the PAA backbone in a single step, thereby obtaining a defined homogeneous sequence. Furthermore, reaction at 366 nm in FEP tubing in the flow reactor enabled the large‐scale synthesis of an fluorenylmethyloxycarbonyl (Fmoc)‐protected glycosylated building block, which was shown to be suitable for solid‐phase synthesis and will also allow heterogeneous sequence control of different carbohydrates along the oligomeric backbone. These developments enable the synthesis of sequence‐defined carbohydrate‐functionalised PAAs with potential biological applications.
Traceless Chelation‐Controlled Rhodium‐Catalyzed Intermolecular Alkene and Alkyne Hydroacylation
Authors: Hooper Joel F. , Young Rowan D. , Weller Andrew S. , Willis Michael C.
Published: January 2013

A new functional‐group tolerant, rhodium‐catalyzed, sulfide‐reduction process is combined with rhodium‐catalyzed chelation‐controlled hydroacylation reactions to give a traceless hydroacylation protocol. Aryl‐ and alkenyl aldehydes can be combined with both alkenes, alkynes and allenes to give traceless products in high yields. A preliminary mechanistic proposal is also presented.
Adsorption Kinetics of Acid Dye Acid Red 88 onto Magnetic Multi‐Walled Carbon Nanotubes‐Fe3C Nanocomposite
Authors: Konicki Wojciech , Pełech Iwona , Mijowska Ewa , Jasińska Izabella
Published: January 2013

Magnetic multi‐walled carbon nanotubes‐Fe3C nanocomposite was synthesized by chemical vapor deposition process and was used as an adsorbent for the removal of acid dye Acid Red 88 (AR88) from aqueous solution. The effects of various parameters such as initial AR88 concentration (10–58 mg L−1), pH (3.1–11.3) and temperature (20–60°C) were investigated. The properties of this adsorbent were characterized by X‐ray diffraction, high‐resolution transmission electron microscopy, energy dispersive X‐ray analysis, fourier transform IR, N2 adsorption/desorption isotherms, and particle size distribution by laser diffraction. The experimental data were analyzed by the Langmuir and Freundlich models of adsorption. Equilibrium data fitted well with the Freundlich model. Kinetic adsorption data were analyzed using the Lagergren pseudo‐first‐order kinetic model, the pseudo‐second‐order model and the intraparticle diffusion model. The regression results showed that the adsorption kinetics was more accurately represented by pseudo‐second‐order model. Thermodynamics parameters, Gibbs free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0), were calculated. All ΔG0 values were negative. The values of ΔH0 and ΔS0 were −4.70 and −7.98 J mol−1 K−1, respectively, indicating that adsorption of AR88 onto magnetic multi‐walled carbon nanotubes nanocomposites was spontaneous and exothermic in nature.
Retinorecipient areas in the diurnal murine rodent Arvicanthis niloticus: A disproportionally large superior colliculus
Authors: Gaillard Frédéric , Karten Harvey J. , Sauvé Yves
Published: January 2013

The Nile grass rat (Arvicanthis niloticus) has a high proportion of cone photoreceptors (∼30–40%) compared with that in the common laboratory mouse and rat (∼1–3%) and may prove a preferable murine model with which to study cone‐driven information processing in retina and primary visual centers. However, other than regions involved in circadian control, little is known about the retinorecipient structures in this rodent. We undertook a detailed analysis of the retinal projections as revealed after intravitreal injection of the anterograde tracer cholera toxin subunit B. Retinal efferents were evaluated in 45 subcortical structures. Contralateral projections were always dominant. Major contralateral inputs consisted of the suprachiasmatic nucleus, dorsolateral geniculate nucleus (dLGN), intergeniculate leaflet, ventral geniculate nucleus (magnocellular part), lateroposterior thalamic nucleus, all six pretectal nuclei, superficial layers of the superior colliculus (SC), and the main nuclei of the accessory optic system. Terminals from the contralateral eye were also localized in an unnamed field rostromedial to the dLGN as well as in the subgeniculate thalamic nucleus. Ipsilateral inputs were found mainly in the suprachiasmatic nucleus, dLGN, intergeniculate leaflet, internal sector of the magnocellular part of the ventral geniculate nucleus, olivary pretectal nucleus, and SC optic layer. Retinal afferents were not detected in the basal forebrain or the dorsal raphe nucleus. Morphometric measurements revealed that the superficial layers of the SC are disproportionately enlarged relative to other retinorecipient regions and brain size compared with rats and mice. We suggest that this reflects the selective projection of cone‐driven retinal ganglion cells to the SC. J. Comp. Neurol. 521:1699–1726, 2013. © 2012 Wiley Periodicals, Inc.
An Interference‐Free Glucose Biosensor Based on an Anionic Redox Polymer‐Mediated Enzymatic Oxidation of Glucose
Authors: Deng Huimin , Shen Wei , Gao Zhiqiang
Published: January 2013

Herein a novel strategy for the construction of an amperometric biosensor for highly sensitive and selective determination of glucose is described. The biosensor is made of a biocomposite membrane of glucose oxidase (GOx) and an Os(bpy)2 (bpy=2,2′‐bipyridine)‐based anionic redox polymer (Os‐RP) mediator. The biosensor is fabricated through the co‐immobilization of GOx and the Os‐RP on the surface of a glassy carbon electrode by a simple one‐step chemical crosslinking process. The crosslinked Os‐RP/GOx composite membrane shows excellent catalytic activity toward the oxidation of glucose. Under optimal experimental conditions, a linear correlation between the oxidation current of glucose in amperometry at 0.25 V (vs. Ag/AgCl) and glucose concentration up to 10 mM with a sensitivity of 16.5 μA mM−1 cm−2 and a response time <5 s. Due to the presence of anionic sulfonic acid groups in the backbone of the redox polymer, the biosensor exhibits excellent selectivity to glucose in the presence of ascorbic acid and uric acid. The low hydrophobicity of the composite membrane also effectively retards the transport of molecular oxygen within the membrane.
Synthesis of Nanovoid Bi2WO6 2D Ordered Arrays as Photoanodes for Photoelectrochemical Water Splitting
Authors: Zhang Liwu , Bahnemann Detlef
Published: January 2013

Herein we report a facile and economic method to prepare nanovoid Bi2WO6 2D ordered arrays employing a simple self‐assembly procedure. The electrochemical properties and performance of the 2D nanoarray as a photoanode for water splitting are investigated and compared with a conventional photoanode of similar thickness. The 2D array photoanode shows a much higher photocurrent density and photon‐to‐H2 conversion efficiency even with a small content of the Bi2WO6 material. The enhancement is further studied and explained on the basis of the superiority of light scattering and photogenerated hole diffusion within the 2D array structure. This work provides a facile method to improve the efficiency of solar energy conversion systems by minimizing the charge‐carrier diffusion length and reducing the light reflection, as well as reducing the amount of the semiconductor material (often costly and/or rare) present in the photoanode.
Assessment of a novel flow cytometry technique of one‐step intracellular staining: Example of FOXP3 in clinical samples
Authors: Demaret Julie , Saison Julien , Venet Fabienne , Malcus Christophe , Poitevin‐Later Francoise , Lepape Alain , Ferry Tristan , Monneret Guillaume
Published: January 2013

Background:

By measuring multiple parameters on a single‐cell basis, flow cytometry is a potent tool to dissect the phenotypes and functions of cell subsets. However, because this technique may be time‐consuming, particularly for intracellular staining, it could be problematic for its use in daily routine or in large cohorts. Recently, a novel reagent has been developed to perform intracellular staining in one step. The objective of our study was thus to assess this new method in comparison with the reference technique by focusing on FOXP3 staining in clinical samples.

Methods:

Peripheral blood was collected from 15 HIV‐1‐infected patients, 5 critically ill patients, and 5 healthy volunteers and stained using the two different methods. Different subsets of FOXP3 positive cells were investigated by flow cytometry.

Results:

When comparing results obtained with the two techniques, no statistical differences between the percentages of CD4+FOXP3+, CD4+CD25+FOXP3+, and CD4+CD25+CD127−FOXP3+ cells were observed. Besides, a strong correlation between percentages of CD4+FOXP3+CD25+CD127− lymphocytes measured with both techniques was found in patients (r: 0.843, P < 0.001, intra‐class correlation coefficient: 0.820, P < 0.001). Importantly, flow cytometry stainings obtained with the one‐step method were very robust with an excellent intra‐assay precision, a better discriminative power and correct stability and reproducibility of the staining even after blood storage.

Conclusions:

With a strong correlation between the percentages of FOXP3+ Tregs when compared with the reference method, a better staining quality, a shorter realization time and no need of isotype control, this one step procedure may represent an important improvement for a daily routine use of intracellular staining. © 2012 International Clinical Cytometry Society
Intra‐ and interlaboratory variability of paroxysmal nocturnal hemoglobinuria testing by flow cytometry following the 2012 Practical Guidelines for high‐sensitivity paroxysmal nocturnal hemoglobinuria testing
Authors: Marinov Iuri , Kohoutová Martina , Tkáčová Vlasta , Lysák Daniel , Holubová Monika , Stehlíková Olga , Železníková Tatiana , Žontar Darja , Illingworth Andrea
Published: January 2013

Background

Sutherland et al. recently published the Practical Guidelines for high‐sensitivity detection of paroxysmal nocturnal hemoglobinuria (PNH) clones by flow cytometry (FCM), containing concise protocols for PNH testing.

Methods

Using this approach, we studied the intra‐ and interlaboratory variability observed in a multicenter study in which fresh blood samples containing three clinically relevant PNH clone sizes within the granulocytic, monocytic, and red blood cell (RBC) populations were shipped to each participating center.

Results

Coefficients of variation (CVs) for precision/reproducibility analysis ranged from 0.01%/0.02% to 0.48%/0.45% (big clone), from 0.69%/1.52% to 4.24%/5.80% (small‐intermediate clone), from 1.47%/3.91% to 15.01% /17.83% (minor clone) for PNH white blood cells (WBCs) and from 0.24%/0.48% to 1.76%/1.83% (big clone), from 0.80%/1.14% to 2.39%/4.45% (small‐intermediate clone), from 1.09%/3.36% to 10.54%/10.23% (minor clone) for PNH RBCs, respectively. Linear regression analysis showed excellent performance correlation between centers (r > 0.99), Wilcoxon rank test revealed no statistically significant differences for PNH granulocytes, monocytes, and RBCs (P > 0.05%), Bland–Altman analysis demonstrated good performance agreement for all target PNH clones (mean bias ranging from −1.47 to 0.71).

Conclusion

Our results demonstrate very good intra‐ and interlaboratory performance characteristics for both precision and reproducibility analyses and excellent correlation and agreement between centers for all target PNH clone sizes. Our data confirm the reliability and robustness of the recently published Practical Guidelines approach for high sensitivity PNH testing by flow cytometry and suggest that such an approach represents an excellent basis for standardization of PNH testing by flow cytometry. © 2013 International Clinical Cytometry Society
L‐selectin shedding by NSAIDs: Old friends in new dresses
Authors: Zarbock Alexander , Rossaint Jan
Published: January 2013

The recruitment of leukocytes to sites of inflammation requires the highly organized interplay of cell adhesion molecules on both leukocytes and inflamed endothelial cells, and disrupting the interaction of these molecules may compromise efficient recruitment of immune cells. Non‐steroidal anti‐inflammatory drugs inhibit inflammatory responses by several mechanisms including inhibition of prostaglandin synthesis and decreasing the expression of cell surface adhesion molecules. A report by Herrera‐Garcia et al. [Eur. J. Immunol. 2013. 43: 55–64] in this issue of the European Journal of Immunology shows that the non‐steroidal anti‐inflammatory drug N‐phenylanthranilic acid (N‐Ph) causes L‐selectin to be shed from the leukocyte plasma membrane and that this process in turn causes a decrease in leukocyte recruitment during inflammation in vivo. This finding may lead to novel approaches using N‐Ph in the control of inflammatory processes as discussed in this Commentary.
DEXterity of tolerogenic APCs
Authors: Stagliano Katherine E. R. , Oppenheim Joost J.
Published: January 2013

A promising therapeutic approach for inducing tolerance in autoreactive T cells is the use of APCs such as DCs and macrophages. In this issue of the European Journal of Immunology, Zheng et al. [Eur. J. Immunol. 2013. 43: 219–227] study the concept of “tolerogenic adjuvants” to induce tolerance via vaccination. These authors have previously identified dexamethasone (Dex) as an effective “tolerogenic adjuvant” and, in this study, they have identified a population of peripheral macrophages that is enriched by Dex treatment and that mediates Dex's tolerogenic effect. In addition to performing a phenotypic characterization of this population, the authors noted an increase in serum levels of IL‐10 and Treg cells after Dex treatment of mice. As discussed in this Commentary, by employing Dex as a tolerogenic adjuvant in the presence of relevant peptides, we may have a means of restoring specific immune tolerance in cases of autoimmune disease and allergy.
Spin Crossover in Polymeric Materials Using Schiff Base Functionalized Triazole Ligands
Authors: Scott Hayley S. , Ross Tamsyn M. , Moubaraki Boujemaa , Murray Keith S. , Neville Suzanne M.
Published: January 2013

Functionalized 1,2,4‐(R)‐triazole‐based Schiff base (R‐N=CH‐R′) ligands have been incorporated into spin crossover 1D materials of the general formula [Fe(Xtrz)3](A)2·2H2O (A = BF4, ClO4, Br, NO3; Xtrz = triazole liands). The ligand N‐salicylidene 4‐amino‐1,2,4‐triazole (Hsaltrz) and the novel ligand N‐cinimalidene 4‐amino‐1,2,4‐triazole (Hcintrz) were targeted to assess the implication of incorporating various aromatic functional groups on the spin crossover properties of this well‐known family of one‐dimensional materials. Magnetic susceptibility measurements on the polycrystalline powdered materials [Fe(Hsaltrz)3](A)2·2H2O [A = BF4 (1), ClO4 (2), Br (3)] and [Fe(Hcintrz)3](A)2·1.5(H2O) [A = BF4 (4), ClO4 (5), Br (6)] revealed spin transitions over the range T${1 \over 2}$ = 100–225 K. The spin crossover properties of the dehydrated materials were also investigated [1–6(dh)]. In attempts to prepare single crystals of these materials a dinuclear {[Fe2(Hsaltrz)5(NCS)4]·2MeOH (7)} and a trinuclear {[Fe3(Hsaltrz)6(H2O)2(EtOH)4](ClO4)6·2(EtOH) (8)} complex were obtained; these materials remain high spin over all temperatures and display weak antiferromagnetic exchange coupling. The structure of the novel ligand Hcintrz (9) is reported.
Synthesis of Functionalized Hexadentate Iminopyridine FeII Complexes – Toward Anion‐Dependent Spin Switching in Polar Media
Authors: McDaniel Ashley M. , Klug Christina M. , Shores Matthew P.
Published: January 2013

We report the syntheses and characterizations of low‐spin FeII complexes of hexadentate ligands poised for anion‐triggered spin‐state switching in polar solutions: [Fe(L5‐OH)](BF4)2 (1) and [Fe(L5‐ONHtBu)](BF4)2 (3), in which L5‐OH and L5‐ONHtBu are tripodal iminopyridine ligands that contain methanolic or tert‐butylamide functional groups, respectively, bound meta to the pyridyl N donor atom. Solid‐state evidence for strong hydrogen bonding between Cl– anions and all three amide functional groups in [Fe(L5‐ONHtBu)]2+ is provided by the crystal structure of {[Fe(L5‐ONHtBu)]⊂Cl}2[FeCl4] (2). In ambient‐temperature acetonitrile solutions of 1 and 3, chloride ion titrations produce marked changes in the 1H NMR spectra, including large downfield shifts for the amide NH and hydroxy OH resonances, which indicates strong anion binding events. Interestingly, for amide‐containing 3, we observe small changes in magnetic susceptibility as (nBu4N)Cl is added, which suggests that spin‐state control by anion–cation interactions may be accessible for related compounds with weaker ligand fields.
Catalytic Hydrolysis of Adenosine Triphosphate (ATP) by Antitumoral ϵ‐Keggin Core Compound, [H2MoV12O28(OH)12(MoVIO3)4]6–, at pH 5 and 7.5
Authors: Ishikawa Eri , Yamase Toshihiro
Published: January 2013

The hydrolysis of adenosine triphosphate (ATP) [to adenosine diphosphate (ADP) and phosphate] at 40 °C by [Me3NH]6[H2MoV12O28(OH)12(MoVIO3)4]·2H2O (PM‐17) as an important candidate for antitumor chemotherapy is investigated with the help of 31P NMR spectroscopy, electrospray ionization mass spectrometry (ESI‐MS), and isothermal titration calorimetry (ITC). The ATP hydrolysis at pH 5 and 7.5 proceeds catalytically to yield ADP, HnPO4(3–n)–, adenosine monophosphate (AMP), and [(PO4)2Mo5O15]6–. AMP and [(PO4)2Mo5O15]6– result from the secondary step of the ATP hydrolysis: the former was produced by the hydrolysis of ADP (with the liberation of phosphate), and the latter by the condensation among phosphates and monomolybdates (derived from the partial release of the MoVIO3 moieties from the PM‐17 anion). The enhancement of the ATP hydrolysis in the presence of K+ is discussed in terms of the electrostatic interaction of K+ at the Pγ phosphate in the negatively charged ATP 5′‐triphosphates, which accompanies the coordination of PM‐17 anions with a resultant conformational constraint of this phosphate. Values of thermodynamic parameters for the interaction between ATP and PM‐17 at pH 7.5 suggest the K+‐mediated assembly of PM‐17 anions at the 5′‐triphosphate chain (matrix effect), which leads to a decrease in the ATP hydrolysis owing to the depressed activation of the Pγ–O–Pβ linkage.
Dimerized Spin‐Crossover Iron(II) Complexes as Supramolecular Anion Capsules
Authors: Shiga Takuya , Oshiro Emiko , Nakayama Naoko , Mitsumoto Kiyotaka , Newton Graham N. , Nishikawa Hiroyuki , Oshio Hiroki
Published: January 2013

Two dimerized iron(II) complexes, [{Fe(L)(HL)2}{Fe(HL)3}](PF6)(BF4)2·5CH3CN·4H2O (1) and [{Fe(L)(HL)2}{Fe(HL)3}](PF6)(FeCl4)2 (2) {HL = 3‐(2‐pyridyl)‐5‐[4‐(diphenylamino)phenyl]‐1H‐pyrazole}, supported by triphenylamine‐derivatized bidentate ligands and encapsulating hexafluorophosphate ions were synthesized. The complex iron ions have octahedral coordination geometries in which they interact with six nitrogen atoms from three bidentate ligands. Both compounds have capsule‐like dimerized supramolecular structures, in which the arrangements of the bulky ligands of two discrete mononuclear complexes create a central cavity in which a single hexafluorophosphate ion is captured. The bidentate ligands interact with the anionic guest molecules through the hydrogen atoms of the ligand pyrazole moieties. Cryomagnetic studies reveal that both compounds show spin‐crossover behavior. Complex 1 showed quasi‐reversible spin‐crossover around 200–300 K, hindered by desolvation effects, whereas 2 showed reversible gradual spin‐crossover behavior. The electronic states of the iron ions resulting from the spin‐crossover were confirmed by X‐ray structure analyses and Mössbauer spectra.
Influence of harvest year and cultivar on wax composition of olive oils
Authors: Giuffrè Angelo Maria
Published: January 2013

Olive oils extracted from Italian cultivars grown in the Region of Calabria, Southern Italy were analyzed for their wax ester composition, for three successive harvest years. Three autochthonous cultivars from Calabria: Cassanese, Ottobratica, and Sinopolese and seven allochtonous cultivars: Coratina, Itrana, Leccino, Nocellara Messinese, Nociara, Pendolino, and Picholine were considered. This work demonstrates the presence of significant differences (ANOVA) for the different wax ester compounds present in these olive oils, taking into consideration the cultivar and the harvest year. The studied olive oils present a good wax ester composition according to both EU and IOC regulations. The cultivar Ottobratica showed the highest wax ester content, whereas Itrana presented the lowest content.

Practical applications: Wax esters are naturally present on the drupe cuticle and are transferred into olive oil by means of mechanical extraction and especially by solvent extraction on an industrial scale. They are a legal parameter contained in the European Union regulation and in the International Olive Oil Council regulation. Wax esters are a quality indicator for olive oil evaluation, especially to detect a fraudulent admixture of pomace olive oil in labeled extra virgin olive oil or in labeled monocultivar extra virgin olive oil. The adaptability of allochthonous cultivars in a different geographical area is also demonstrated.
Machine‐to‐machine communications via airliners
Authors: Plass Simon , Berioli Matteo , Hermenier Romain , Liva Gianluigi , Munari Andrea
Published: January 2013

Within this article, a new concept for machine‐to‐machine communications infrastructure via airliners is presented. The main principles and resulting challenges are described, together with a first study on possible coverage within Europe and North America using airliners that endorses the concept's feasibility. Accurate insights are drawn by taking into account all commercial flights during 24 h on the basis of real global flight data. We strengthen the proposed solution by investigating system dimension aspects in a proof‐of‐principle manner as well as by discussing medium access policies and coding strategies capable of achieving performance improvements over alternative architectures. The goal of the article is to stimulate further research activities and ideas in this area. Copyright © 2013 John Wiley & Sons, Ltd.
Mirabegron use in the treatment of overactive bladder symptoms
Authors: Digesu G Alessandro , Gore Michelle , Khullar Vik
Published: January 2013

Beta‐3 adrenoreceptors have been proposed as a target in the treatment of OAB due to their role in the mediation of bladder smooth muscle relaxation. Mirabegron is an oral medication that selectively targets beta‐3 adrenoreceptors and has been shown to reduce rhythmic abnormal detrusor contractions in animal models. In this Drug profile the authors present the clinical data relating to its efficacy and adverse effects and discuss its potential place in the treatment of OAB. Copyright © 2013 John Wiley & Sons, Ltd.
Linaclotide for irritable bowel syndrome with constipation
Authors: Chaplin Steve
Published: January 2013

Linaclotide is a guanylate cyclase agonist that promotes increased stool water content, which increases bowel movement frequency. It has recently received a positive opinion from the CHMP for the treatment of constipation‐predominant IBS. In this Drug profile Steve Chaplin presents the clinical data relating to its efficacy and adverse events. Copyright © 2013 John Wiley & Sons, Ltd.
Hydrogen Tungsten Bronze‐Supported Platinum as Electrocatalyst for Methanol Oxidation
Authors: Li X. P. , Xiang X. D. , Yang H. Y. , Wang X. J. , Tan C. L. , Li W. S.
Published: January 2013

Hydrogen tungsten bronze (HxWO3)‐supported platinum was prepared by electrodeposition and used as an electrocatalyst for methanol oxidation. The prepared electrocatalyst was characterized by Raman spectrum, X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), cyclic voltammetry (CV), and chronoamperometry (CA). It is found that the support, HxWO3, not only reduces the platinum particle size and thus reduces the platinum loading, but also provides platinum with the anti‐poison ability to carbon monoxide and thus improves the activity of platinum toward methanol oxidation.
A critical role for the cholesterol‐associated proteolipids PLP and M6B in myelination of the central nervous system
Authors: Werner Hauke B. , Krämer‐Albers Eva‐Maria , Strenzke Nicola , Saher Gesine , Tenzer Stefan , Ohno‐Iwashita Yoshiko , De Monasterio‐Schrader Patricia , Möbius Wiebke , Moser Tobias , Griffiths Ian R. , Nave Klaus‐Armin
Published: January 2013

The formation of central nervous system myelin by oligodendrocytes requires sterol synthesis and is associated with a significant enrichment of cholesterol in the myelin membrane. However, it is unknown how oligodendrocytes concentrate cholesterol above the level found in nonmyelin membranes. Here, we demonstrate a critical role for proteolipids in cholesterol accumulation. Mice lacking the most abundant myelin protein, proteolipid protein (PLP), are fully myelinated, but PLP‐deficient myelin exhibits a reduced cholesterol content. We therefore hypothesized that “high cholesterol” is not essential in the myelin sheath itself but is required for an earlier step of myelin biogenesis that is fully compensated for in the absence of PLP. We also found that a PLP‐homolog, glycoprotein M6B, is a myelin component of low abundance. By targeting the Gpm6b‐gene and crossbreeding, we found that single‐mutant mice lacking either PLP or M6B are fully myelinated, while double mutants remain severely hypomyelinated, with enhanced neurodegeneration and premature death. As both PLP and M6B bind membrane cholesterol and associate with the same cholesterol‐rich oligodendroglial membrane microdomains, we suggest a model in which proteolipids facilitate myelination by sequestering cholesterol. While either proteolipid can maintain a threshold level of cholesterol in the secretory pathway that allows myelin biogenesis, lack of both proteolipids results in a severe molecular imbalance of prospective myelin membrane. However, M6B is not efficiently sorted into mature myelin, in which it is 200‐fold less abundant than PLP. Thus, only PLP contributes to the high cholesterol content of myelin by association and co‐transport. © 2013 Wiley Periodicals, Inc.
Analytical studies on transient groundwater flow induced by land reclamation using different fill materials
Authors: Hu Litang , Jiao Jiu Jimmy
Published: January 2013

Land reclamation may have a significant influence on groundwater regimes. Analytical solutions have been developed in the past to study the impact of land reclamation on a steady‐state groundwater flow and transient flow in fill materials, assuming that the reclamation site consists of a single zone of uniform hydraulic parameters. In this paper, we derive analytical solutions to describe the transient water table change in response to multi‐stage land reclamation where the fill material is uniform in each stage but the hydraulic conductivity of the fill material varies from stage to stage. By introducing the method of separation of variables, we develop a transient analytical solution to study the impact of land reclamation consisting of fill material with different hydraulic properties on groundwater dynamics. The results show that the water table first increases significantly into the reclaimed zone following the fill material deposition, and then the increase gradually propagates into the original aquifer. The change of water table in the original aquifer mainly depends on the value of hydraulic conductivity of the fill materials. Examples in this paper illustrate how the aquifer system experiences a long time unsteady‐state flow as a result of the reclamation, and it takes at least tens of years for the system to approach a new equilibrium. It is suggested that for a large‐scale reclamation project, the response of the groundwater regime to reclamation should be carefully studied. Copyright © 2013 John Wiley & Sons, Ltd.
Pain catastrophizing moderates the effects of pain‐contingent task interruptions
Authors: Schrooten M.G.S. , Karsdorp P.A. , Vlaeyen J.W.S.
Published: January 2013

Background

A prominent behavioural consequence of pain is the temporary suspension of current activities with intent to resume them later. Little is known about the effects of such pain‐contingent task interruptions. This experiment examines the influence of pain‐contingent interruptions on the amount of time spent performing a cognitive achievement task: We expected that people would spend more time on task when task performance was interrupted in response to pain (vs. no interruption), and that negative mood and pain catastrophizing would enhance this negative impact.

Methods

Healthy volunteers read behaviour descriptions until they felt they could form a good impression. Before task performance, participants underwent a negative or positive mood induction. During the task, all participants expected painful stimulation. Half of the participants in each mood induction group received an acute (electrocutaneous) pain stimulus, resulting in a 2‐min break from the task. The other participants received no sensory stimulation during task performance and their performance was not interrupted.

Results

Results revealed no effect of mood on task performance (i.e., total number of descriptions read). There was, however, a significant interaction between task interruption and pain catastrophizing, indicating that participants with low levels of catastrophizing tended to read more descriptions when performance was interrupted than when not, whereas participants reporting relatively high levels of catastrophizing showed the reverse behavioural pattern.

Conclusions

The impact of pain‐contingent task interruptions was reversed in participants reporting relatively high levels of pain catastrophizing. Results are discussed with regard to interruption management in the context of chronic pain.
Impact of CCR2 and SDF1 Polymorphisms on Disease Progression in HIV‐Infected Subjects in Thailand
Authors: Ammaranond Palanee , Sanguansitthianan Sayompoo , Phaengchomduan Poonlaph , Sae‐Lee Chanachai , Mardkhumchan Sirimarn
Published: January 2013

Background

The genotypic polymorphisms of CCR5, CCR2, and SDF1 were analyzed to determine their impact as potential confounders with regard to disease progression because of the role that host genetic factors appear to be involved in determining rates of disease progression. J. Clin. Lab. Anal. 27:38–44, 2013. © 2012 Wiley Periodicals, Inc.

Methods

Genomic DNA was extracted from Ethylenediaminetetraacetate whole blood using Qiagen DNA extraction kit . The amplification of CCR5, CCR2, and SDF1 genes was performed by PCR.

Results

Two hundred and twenty‐one samples were genotyped for the CCR5, CCR2, and SDF1 mutation. Among these, all (100%) were identified as wild type for CCR5. All were then investigated considering the impact on CD4+ T‐cell counts. Samples were divided into two groups based on the CD4+ T‐cell numbers. It revealed that in the group of CD4+ T‐cell counts ≥200 cells/μl, 15 were found for the homozygous for SDF1 gene (3′A/3′A) whereas one was found in the group of CD4+ T‐cell counts <200 cells/μl. Homozygosity for the CCR2 polymorphisms (64I/64I) were five in the group of CD4+ T‐cell counts ≥200 cells/μl and none were found in the group of CD4+ T‐cell counts <200 cells/μl. These results demonstrated that there was a significant association between CD4+ T‐cell numbers and CCR2 and SDF1 polymorphisms (P < 0.001).

Conclusions

The mutation of CCR2 and SDF1 genes showed a significant difference in the distribution of CD4+ T‐cell numbers (P < 0.001) whereas mutation of chemokine coreceptor CCR5 was not appeared to be associated with the impact of CD4+ T‐cell counts.
Biochemical Markers of Oxidative and Nitrosative Stress in Acne Vulgaris: Correlation With Disease Activity
Authors: Al‐Shobaili Hani A. , Alzolibani Abdullateef A. , Al Robaee Ahmad A. , Meki Abdel‐Raheim M.A. , Rasheed Zafar
Published: January 2013

Background

Acne vulgaris is a multifactorial skin disorder of unknown etiology. Free radical‐mediated reactions have been implicated but their role in eliciting this response and contributing to disease progress remains unexplored. This study was undertaken to investigate the status and contribution of oxidative/nitrosative stress in patients with acne vulgaris. J. Clin. Lab. Anal. 27:45–2, 2013. © 2012 Wiley Periodicals, Inc.

Methods

Sera from 50 acne vulgaris with varying levels of disease activity (mild, moderate, and severe) according to the Global Acne Grading System (GAGS) and 40 age‐ and sex‐matched controls were evaluated for serum levels of oxidative/nitrosative stress markers, including protein oxidation, lipid peroxidation and nitric oxide (NO), superoxide dismutase (SOD), and glutathione (GSH).

Results

Serum analysis showed significantly higher levels of carbonyl contents, malondialdehyde (MDA) and NO, in acne patients compared with healthy controls (P < 0.05). Interestingly, not only there were an increased number of subjects positive for carbonyl contents, but also the levels of these oxidants were significantly increased with the increase of the disease activity (P < 0.05). In addition, a significant correlation was observed between the levels of carbonyl contents and the GAGS scores (r = 0.341, r = 0.355, and r = 0.299, respectively). Furthermore, sera from acne patients had lower levels of SOD and GSH compared with healthy control sera.

Conclusion

These findings support an association between oxidative/nitrosative stress and acne. The stronger response observed in serum samples from patients with higher GAGS scores suggests that markers of oxidative/nitrosative stress may be useful in evaluating the progression of acne and in elucidating the mechanisms of disease pathogenesis.
Improved Allele‐Specific PCR Technique for Kidd Blood Group Genotyping
Authors: Intharanut Kamphon , Grams Rudi , Bejrachandra Sasitorn , Sriwanitchrak Pramote , Nathalang Oytip
Published: January 2013

Background

We developed an allele‐specific polymerase chain reaction (AS‐PCR) technique for Kidd blood group genotyping. J. Clin. Lab. Anal. 27:53–58, 2013. © 2012 Wiley Periodicals, Inc.

Methods

Altogether, 340 blood samples from Thai blood donors at the National Blood Centre, Thai Red Cross Society, were tested with anti‐Jka and anti‐Jkb using the gel technique and the direct urea lysis test was used for screening Jk(a−b−) phenotype. For AS‐PCR technique, different types of primers were used for JK*01 and JK*02 allele detections in known DNA controls.

Results

Regarding JK*02 allele detection, the pseudopositve amplification products were found when using correctly matched forward primer and a single mismatch forward primer. Interestingly, one type of two mismatch pairing at the 3′ end of the forward primer can be used together with the newly designed reverse primer for Kidd blood group genotyping. It was found that the typing results in all samples obtained by serological techniques and newly developed AS‐PCR technique were in agreement and this PCR technique also gave 100% concordance of results in 30 samples randomly tested twice and demonstrated reproducible results.

Conclusion

This study shows that the in‐house AS‐PCR is simple, cost‐effective, and convenient for Kidd blood group genotyping in routine laboratories, especially, in resolving serologic investigations.