bluuebunny/crossref_metadata_2025 huggingface dataset:
Analytical Chemistry on the Femtoliter Scale
Authors: Gorris Hans H. , Walt David R.
Published: April 2010

The compartmentalization of reactions in femtoliter (fL) containers and integration of fL containers into arrays not only enhances and accelerates chemical and biochemical analysis but also leads to new scientific methods and insights. This review introduces various fL container and array formats and explores their applications for the detection and characterization of biologically relevant analytes. By loading analytes, sensing elements, or cells into fL arrays, one can perform thousands of analytical measurements in parallel. Confining single enzyme molecules in fL arrays enables one to analyze large numbers of individual enzyme molecules simultaneously in solution. New nanofabrication techniques and progressively more sensitive detection methods drive the field of fL analytical chemistry. This review focuses on the progress and challenges in the field of fL analytical chemistry with examples of both basic and applied research.
Characterizing seabird bycatch in the eastern Australian tuna and billfish pelagic longline fishery in relation to temporal, spatial and biological influences
Authors: Trebilco Rowan , Gales Rosemary , Lawrence Emma , Alderman Rachael , Robertson Graham , Baker G. Barry
Published: April 2010

Seabirds killed incidentally in Australia's eastern tuna and billfish (ETBF) longline fishery between September 2001 and June 2006 were examined to evaluate species composition and to relate, where possible, capture events to operational and environmental factors.

During this period 2.129 million hooks on 2202 shots were observed, and 369 birds were reported killed. The majority (78%) of these were flesh‐footed shearwaters (Puffinus carniepes), 53% of which were male and 44% female. Smaller numbers of medium to large sized albatrosses (Diomedeidae, predominantly female) and other shearwaters (Puffinus spp.) and petrels (Pterodroma spp.) dominated the remainder of the bycatch.

Of the 369 birds reported taken as bycatch, 280 were available for necropsy, and species identifications performed in situ by observers were assessed. While observer identifications were generally correct for common species, performance was poor for less common ones.

The geographical location (latitude) of shots, season, time of day at which shots were set, and bait type and life status (dead or alive) influenced the seabird bycatch rate. The majority of captures (87% overall) occurred between 30 and 35°S, with bycatch being lowest in winter, and remaining at similar levels across the other seasons.

The use of live fish bait was generally associated with increased captures of both seabirds overall, and flesh‐footed shearwaters in particular. Copyright © 2010 John Wiley & Sons, Ltd.
Alendronate Affects Cartilage Resorption by Regulating Vascular Endothelial Growth Factor Expression in Rats
Authors: Kang J.H. , Choi N.K. , Kang S.J. , Yang S.Y. , Ko H.M. , Jung J.Y. , Kim M.S. , Koh J.T. , Kim W.J. , Oh W.M. , Kim B.Y. , Kim S.H.
Published: April 2010

This study was performed to determine effects of alendronate on the tibial proximal epiphyseal cartilage undergoing endochondral ossification and the expression of vascular endothelial growth factor (VEGF) from the cartilage. Alendronate was injected subcutaneously every other day in postnatal Day 1 Sprague Dawley rats. The rats were sacrificed 3, 5, 7, and 10 days after the first injection. The effect of alendronate treatment for 10 days was demonstrated from the morphological change that the area of the secondary ossification center in the epiphysis was significantly smaller in the alendronate group than that in the control group (P < 0.05). Strong immunoreactivity to VEGF was observed in the hypertrophied chondrocytes and some proliferating chondrocytes in the epiphyseal cartilage at postnatal Day 5 and was decreased after the alendronate treatment for 5 days. Immunoreactivity was observed in not only hypertrophied cells but also the peripheral cartilaginous matrix adjacent to the vascular canals invading into the central portion of the cartilage at postnatal Day 7. This reactivity was also reduced considerably by the alendronate treatment for 7 days. The level of VEGF expression was reduced by the alendronate treatment at both the transcription and translation levels. However, the transcriptional level of the flt‐1 and flk‐1 receptors was relatively unaltered by the treatment. These results suggest that VEGF expression is required for vascular invasion into the developing cartilage and alendronate can affect its resorption by downregulating VEGF expression. Anat Rec, 293:786–793, 2010. © 2010 Wiley‐Liss, Inc.
Bücherschau
Authors: Askenasy
Published: April 2010

Die Zeitalter der Chemie in Wort und Bild. Von Dr. Albert Stange. 528 Seiten. Mit vielen Porträts und Abbildungen nach Originalen. Leipzig 1908. Verlag von Otto Wigand. Preis broch. 16 Mk., geb. 18 Mk.

Band III der Laboratoriumsbücher für die chemische und verwandte Industrien: Laboratoriumsbuch für die Industrie der Riechstoffe. Von Dr. Oskar Simon. 68 Seiten. Halle a. S. Verlag von Wilhelm Knapp. Preis 3 Mk.
Das elektromotorische Verhalten von Uranyl‐Uranogemengen
Authors: Luther R. , Michie Arthur C.
Published: April 2010

Zusammenfassung

Uranosalze sind auch in sauren Lösungen starke und rasche Reduktionsmittel. Die Oxydation der Uranolösungen durch Luftsauerstoff wird durch Platinschwarz, Eisensalze und insbesondere Kupfersalze stark beschleunigt.

Gemenge von Urano‐ und Uranylsulfatlösungen zeigen bei Gegenwart von Säure eine konzentrationsrichtige Abhängigkeit der EMK von der Konzentration der beteiligten Stoffe gemäß der Formel

Der Wert von ε0 in dieser Formel ist gegen den Nernstschen Nullpunkt um 0,419 Volt, gegen den Ostwaldschen Nullpunkt um 0,696 positiver.

Merkurosulfatelektroden in nicht zu verdünnter Schwefelsäure zeigen eine geringe Abhängigkeit der EMK von der Konzentration der Schwefelsäure, was in guter Uebereinstimmung mit der Theorie der zweistufigen Dissoziation der Schwefelsäure steht.

Leipzig‐Dresden‐Wallsend on Tyne, 1903 bis 1908.
XVI. Hauptversammlung der Deutschen Bunsen‐Gesellschaft für angewandte physikalische Chemie: Über den Einfluss von Fremdkörpern auf das Zustandsdiagramm der Eisen‐Kohlenstofflegierungen
Authors: Goerens P.
Published: April 2010

Die Resultate der vorliegenden Arbeit lassen sich in folgende Sätze kurz zusammenfassen:

Unter Benutzung des Beispiels Blei‐Zinn Wismut wurde eine körperliche Darstellung für ternäre Zustandsdiagramme ausgearbeitet, welche dadurch erfolgt, daß man das Zustandsdiagramm durch eine Schar von Flächen schneidet, welche senkrecht zur Konzentrationsebene liegen. Zeichnet man die hierdurch entstehenden Teildiagramme auf eine durchsichtige Platte, etwa Celluloidblätter oder präparierte Glasplatten auf, so erhält man ein Raumgebilde, aus welchem die verschiedenen Zustandsräume deutlich zur Anschauung gelangen.

Das ternäre Zustandsdiagramm der Eisen Mangan‐Kohlenstofflegierungen wurde in gleicher Weise ausgearbeitet und zur Darstellung gebracht.

Es wurde festgestellt, daß das ternäre System Eisen Phosphor‐Kohlenstoff sich als ein ähnliches System erweist, wie das Blei‐Zinn Wismutsystem, wenn man annimmt, daß als Komponenten Eisen, Eisenphosphid und Eisencarbid teilnehmen.

Es ließ sich feststellen, daß alle ternären Legierungen des Eisens nach zwei Typen erstarren können.
Dietary methionine intake and neural tube defects in Mexican‐American women
Authors: Graham Anna , Brender Jean D. , Sharkey Joseph R. , Zhu Li , Felkner Marilyn , Suarez Lucina , Canfield Mark A.
Published: April 2010

BACKGROUND

Nutrients other than maternal folic acid are also thought to play a role in preventing neural tube defects (NTDs). Evidence suggests that methionine interacts with folic acid and vitamin B12 in the methylation of contractile proteins involved in closing the neural folds. The role of dietary intake of methionine in NTD risk has not been specifically studied among Mexican Americans, a population with one of the highest prevalences of NTDs in the United States.

METHODS

We conducted a case–control study of 184 Mexican American women with NTD‐affected pregnancies (case women) and 225 women with normal offspring (control women) who resided along the Texas‐Mexico border. The average daily intakes of methionine were calculated from periconceptional food frequency questionnaire data. Women were categorized according to quartiles of daily methionine intake, based on the control mothers' distribution, and the risk for an NTD‐affected pregnancy was calculated using the lowest quartile of intake as the referent.

RESULTS

With adjustment for income, body mass index, hyperinsulinemia, and diarrhea, the odds ratios for increasing quartile of methionine intake were: 0.95 (95% confidence interval [CI], 0.48,1.90), 0.92 (95% CI, 0.46,1.84), and 0.66 (95% CI, 0.30,1.45). Some evidence of interaction between dietary methionine and serum vitamin B12 was noted particularly at higher levels of both components.

CONCLUSIONS

This study was limited by a small sample size but examined this association in an exclusively Hispanic population. Results were suggestive of a potential protective effect for NTDs with increasing maternal dietary methionine intake. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.
Secular trends of hypospadias prevalence and factors associated with it in southeast China during 1993–2005
Authors: Jin Lei , Ye Rongwei , Zheng Junchi , Hong Shixin , Ren Aiguo
Published: April 2010

BACKGROUND

The aim of this study is to describe the prevalence of hypospadias and its time trends during 1993–2005 in southeast China, and to explore the potential risk factors.

METHODS

The study population included all male live and still births (at least 20 weeks of gestation) in 11 cities and counties in Jiangsu and Zhejiang Provinces in Southeast China born during January 1, 1993, through December 31, 2005.

RESULTS

Overall prevalence of hypospadias was 5.8 per 10,000 male births and presented an increasing trend during 1993–2005 (with χ of 3.94, p = 0.047). Prevalence of coronal hypospadias and those with unknown sites increased from 1.7 and 0.3 per 10,000 male births in 1993 to 3.6 and 1.4 per 10,000 male births in 2005, respectively (with χ of 7.29 and 9.05, p = 0.007 and p = 0.002, respectively), but prevalence of perineal hypospadias decreased (with χ of 7.13, p = 0.008). Maternal fever during first trimester, birth of twins or more children, and year of birth were independent risk factors for hypospadias, with odds ratios of 4.14 (95% CI, 1.32–12.83), 3.37 (95% CI, 1.73–6.58), and 1.04 (95% CI, 1.00–1.08), respectively, after adjusting for confounding factors with multivariable logistic regression analysis.

CONCLUSIONS

Prevalence of hypospadias increased during 1993–2005 in the two provinces in southeast China. Maternal fever in the first trimester and birth of twins or more children are associated with the risk for hypospadias. Birth Defects Research (Part A), 2010. © 2010 Wiley‐Liss, Inc.
Great saphenous varicose vein surgery without saphenofemoral junction disconnection
Authors: Zamboni P , Gianesini S , Menegatti E , Tacconi G , Palazzo A , Liboni A
Published: April 2010

Background

The aim of this case–control study was to determine whether preoperative duplex imaging could predict the outcome of varicose vein surgery without saphenofemoral junction (SFJ) disconnection. The duplex protocol included a reflux elimination test (RET) and assessment of the competence of the terminal valve of the femoral vein.

Methods

One hundred patients with chronic venous disease who had a positive RET result and an incompetent terminal valve were compared with 100 patients matched for age, sex, clinical class (Clinical Etiologic Anatomic Pathophysiologic (CEAP) class C2–C6) and disease duration, but who had a positive RET result and a competent terminal valve. All patients underwent ligation and proximal avulsion of the incompetent tributaries from the great saphenous vein trunk without SFJ disconnection. Clinical and duplex follow-up lasted for 3 years, and included Hobbs' clinical score.

Results

Of legs with a competent terminal valve, 100 per cent were rated as cured (Hobbs' class A or B) and 14·0 per cent developed recurrent varices. Patients with an incompetent terminal valve had significantly worse results: 29·0 per cent had Hobbs' class A or B and 82·0 per cent developed recurrence (P < 0·001).

Conclusion

Preoperative duplex assessment of the terminal valve could be used to identify patients suitable for varicose vein surgery without the need for SFJ disconnection.
Chromatographic studies of some cephalosporins on thin layers of silica gel G–zinc ferrocyanide
Authors: Singh Dhruv K. , Maheshwari Gunjan
Published: April 2010

A simple, selective and precise thin‐layer chromatographic method has been developed for the analysis of eight cephalosporin antibiotics, namely cephadroxil, cephalexin, cefixime, cefaclor, cefpodoxime proxetil, cefuroxime axetil, cefotaxime sodium and ceftriaxone sodium. The hRF values of these cephalosporins were investigated on silica gel G–zinc ferrocyanide layers. Mixing of zinc ferrocyanide with silica gel G resulted in a decrease in hRF values, removal of tailing and better resolutions. The influence of silica gel G–zinc ferrocyanide ratio and mobile phases on the chromatographic behavior of cephalosporins on thin layers was investigated. Cephalosporins were selectively separated in their binary and ternary synthetic mixtures and pharmaceutical formulations. Quantitative separations of cephalosporins from their synthetic mixtures were also achieved with good recoveries (97.8–100.3%). Copyright © 2010 John Wiley & Sons, Ltd.
Rational design for variability minimization in bioanalytical method validation: illustration with LC‐MS/MS assay method for terbinafine estimation in human plasma
Authors: Gurule Sanjay , Khuroo Arshad , Monif Tausif , Goswami Dipanjan , Saha Arabinda
Published: April 2010

Terbinafine, a widely used antifungal drug, is a challenging molecule for quantitative bioanalysis due to certain factors contributing assay variability. Despite previous attempts at human plasma determination of terbinafine, exhaustive stability of the drug or an internal standard was lacking. Internal standard stability with negligible variation throughout the analysis is an indicator of a reliable bioanalytical method as the majority of LC–MS/MS assays are based on analyte/IS response ratios for quantitation. A newly developed high‐throughput simple LC‐MS/MS method is described for human plasma determination of terbinafine using naftifine internal standard and eluting all compounds within 2 min. A solid‐phase extraction of terbinafine achieving mean recovery of 84.3% (CV < 4%) without compromising sensitivity (limit of quantitation 5.11 ng/mL) or linearity (5.11–3014.19 ng/mL) is delineated in this paper. A heated nebulizer in positive multiple reaction monitoring mode was employed with transitions m/z 292.2 →141.1 and 288.2 →117.0 for terbinafine and naftifine, respectively, resulting in excellent chromatographic separation on a Hypurity Advance (50 × 4.6 mm, 5 µm) column. The developed method was successfully applied to clinical samples and for the first time demonstrated marked improved extraction efficiency and reliable long‐term plasma stability results without any internal standard response variation during the entire course of study. Copyright © 2010 John Wiley & Sons, Ltd.
Quantitative determination of sparfloxacin in rat plasma by liquid chromatography/tandem mass spectrometry
Authors: Noh Keumhan , Kwon Kwang‐il , Jeong Tae Cheon , Kang Wonku
Published: April 2010

Sparfloxacin, a fluoroquinolone antibiotic, is used for the treatment of bacterial infection. A quantification method using mass spectrometry was developed for the determination of sparfloxacin in rat plasma. After simple protein precipitation with acetonitrile, the analytes were chromatographed on a reversed‐phase C18 column and detected by liquid chromatography/tandem mass spectrometry with electrospray ionization. The accuracy and precision of the assay were in accordance with FDA regulations for validation of bioanalytical methods. This method was applied to measure the plasma sparfloxacin concentrations after a single oral administration of sparfloxacin in rats. Copyright © 2010 John Wiley & Sons, Ltd.
Bioanalytical method development and validation of novel antithrombotic agent S002‐333 by LC‐MS/MS and its application to pharmacokinetic studies
Authors: Bhatta R. S. , Kumar D. , Chhonker Y. S. , Saxena A. K. , Jain G. K.
Published: April 2010

A rapid, sensitive and simple liquid chromatography‐tandem mass spectrometry (LC‐MS/MS) method using an electrospray ionization (ECI) source for the quantification of novel anti‐thrombotic agent S002‐333 [2‐(4‐methoxy‐benzenesulfonyl)‐2,3,4,9‐tetrahydro‐1H‐β‐carboxylic acid amide] in rabbit plasma was developed and validated. The extraction from plasma was carried out by simple protein precipitation extraction method. The chromatographic separation was performed on an Ultramex Cyno, (150 × 4.6 mm, 5 µm) with a guard column, using acetonitrile–water (75:25,v/v) with flow rate of 0.6 mL/min as the mobile phase. The tandem mass spectrometer was tuned in the multiple reaction monitoring mode to monitor them/ztransitions 386.4/215.4 for S002‐333 andm/z393.4/171for the internal standard dexamethasone, using positive ion mode. The MS/MS response was linear over the concentration range from 1.56 to 200 ng/mL, with a lower limit of detection of 0.78 ng/mL. The accuracy and precision of the method were within the acceptable limit of ±20% at the lower limit of quantitation and ±15% at other concentrations and showed no significant matrix effect. The validated method can be used in most or all stages of the screening and optimizing process for future method validation of pharmacokinetic studies Copyright © 2010 John Wiley & Sons, Ltd.
Efficient Acylation of Anisole over Hierarchical Porous ZSM‐5 Structure
Authors: Padmanabhan A. , Selvin R. , Hsu H.‐L. , Xiao L.‐W.
Published: April 2010

Friedel‐Crafts acylation is one of the most important methods to prepare aromatic ketones which are used in manufacturing fine and speciality chemicals, as well as pharmaceuticals. Herein, we report an efficient and convenient procedure for the acylation of anisole with acetic anhydride, using a hierarchical porous ZSM‐5 catalyst. The hierarchical porous ZSM‐5 catalyst was synthesized using styrene butadiene rubber (SBR) as macroporous template. The catalysts were characterized for their structural features by using XRD, SEM, and FT‐IR analyses. The effect of temperature, molar ratio, and catalyst weight on the acylation of anisole was studied in detail. The reaction parameters such as anisole‐to‐acetic anhydride mole ratio, catalyst weight, and reaction temperature were optimized as 5:1, 0.2 g, and 70 °C, respectively. The method described here is environmentally benign and replaces the conventional catalyst by a highly active and reusable catalyst.
Spherical‐particle generation by phase change materials: Near‐monosize particles from emulsions
Authors: Iqbal J. , Ulrich J.
Published: April 2010

The solidification behavior of water‐in‐oil (W/O) emulsion droplets in stagnant pure water was investigated. The droplets were formed from a single capillary tube when the emulsion was pumped by a syringe pump. Different experimental parameters, like surfactant concentration in the preparation of the emulsion, water content in the W/O emulsions, and flow rate, were investigated. The surfactant concentrations were varied from 0.2 to 5 % by volume at different flow rates. The water contents were increased from 5 to 25 % also by volume. The investigation focused on the formation of droplets from a capillary tip. The solidification phenomena of the emulsion drops in the coolant were observed. With higher flow rates, a change from dripping to jetting phenomena was observed. The solid emulsion particles of different sizes were obtained depending on the parameters of the operation. The solid particles were not completely spherical in shape but somewhat ellipsoid.
Highly Modular POP Ligands for Asymmetric Hydrogenation: Synthesis, Catalytic Activity, and Mechanism
Authors: Fernández‐Pérez Héctor , Donald Steven M. A. , Munslow Ian J. , Benet‐Buchholz Jordi , Maseras Feliu , Vidal‐Ferran Anton
Published: April 2010

A library of enantiomerically pure POP ligands (phosphine–phosphite), straightforwardly available in two synthetic steps from enantiopure Sharpless epoxy ethers is reported. Both the alkyloxy and phosphite groups can be optimized for maximum enantioselectivity and catalytic activity. Their excellent performance in the Rh‐catalyzed asymmetric hydrogenation of a wide variety of functionalized alkenes (26 examples) and modular design makes them attractive for future applications. The lead catalyst incorporates an (S)‐BINOL‐derived (BINOL=1,1′‐bi‐2‐naphthol) phosphite group with computational studies revealing that this moiety has a dual effect on the behavior of our POP ligands. On one hand, the electronic properties of phosphite hinder the binding and reaction of the substrate in two out of the four possible manifolds. On the other hand, the steric effects of the BINOL allow for discrimination between the two remaining manifolds, thereby elucidating the high efficiency of these catalysts.
Regularity of minimizers of semilinear elliptic problems up to dimension 4
Authors: Cabré Xavier
Published: April 2010

We consider the class of semistable solutions to semilinear equations −Δu = f(u) in a bounded smooth domain Ω of
\input amssym $\Bbb R^n$
(with Ω convex in some results). This class includes all local minimizers, minimal, and extremal solutions. In dimensions n ≤ 4, we establish an a priori L∞‐bound that holds for every positive semistable solution and every nonlinearity f. This estimate leads to the boundedness of all extremal solutions when n = 4 and Ω is convex. This result was previously known only in dimensions n ≤ 3 by a result of G. Nedev. In dimensions 5 ≤ n ≤ 9 the boundedness of all extremal solutions remains an open question. It is only known to hold in the radial case Ω = BR by a result of A. Capella and the author. © 2010 Wiley Periodicals, Inc.
Ginzburg‐Landau vortex dynamics driven by an applied boundary current
Authors: Tice Ian
Published: April 2010

In this paper we study the time‐dependent Ginzburg‐Landau equations on a smooth, bounded domain Ω ⊂ ℝ2, subject to an electrical current applied on the boundary. The dynamics with an applied current are nondissipative, but via the identification of a special structure in an interaction energy, we are able to derive a precise upper bound for the energy growth. We then turn to the study of the dynamics of the vortices of the solutions in the limit ε → 0. We first consider the original time scale in which the vortices do not move and the solutions undergo a “phase relaxation.” Then we study an accelerated time scale in which the vortices move according to a derived dynamical law. In the dynamical law, we identify a novel Lorentz force term induced by the applied boundary current. © 2010 Wiley Periodicals, Inc.
Electronic structure of smoothly deformed crystals: Cauchy‐born rule for the nonlinear tight‐binding model
Authors: E Weinan , Lu Jianfeng
Published: April 2010

The electronic structure of a smoothly deformed crystal is analyzed using a minimalist model in quantum many‐body theory, the nonlinear tight‐binding model. An extension of the classical Cauchy‐Born rule for crystal lattices is established for the electronic structure under sharp stability conditions. A nonlinear elasticity model is rigorously derived. The onset of instability is briefly examined. © 2010 Wiley Periodicals, Inc.
Compositional dependence of morphology and lattice parameters during growth of K1‐x(NH4)xH2PO4 mixed crystals
Authors: Srinivasan K. , Cantoni A. , Bocelli G.
Published: April 2010

Mixed crystals of ammonium dihydrogen phosphate and potassium dihydrogen phosphate K1‐x(NH4)x H2PO4 were grown from aqueous solutions with x = 0.06, 0.09, 0.15, 0.32, 0.42, 0.51, 0.63, 0.70, 0.76, 0.78, 0.84, 0.88, 0.89 and 0.91. The crystal composition that differs from solution was estimated by X‐ray method. Morphology of the crystals changes from tetragonal prism to needles when the incorporation of either of the two components into the other; which also affects the growth rate along the prominent growth directions significantly. Growth along the [001] decreases initially with composition and reached the maximum when x = 0.5; whereas growth along the [100] always showed a decreasing trend with composition and attained a minimum value when x = 0.5. Crystal length along the [001] and [100] and aspect ratio are also compositional dependent. Unit cell parameters determined by X‐ray powder and single crystal analyses revealed that the ‘a ’ parameter shows only a small and linear variation but the ‘c ’ parameter changes significantly with ADP incorporation because of the difference in the effective ionic radius of K+ and NH4+ ions and also the possibility of NH4+ ion to form two different kinds of hydrogen bonds in the system. The existence of a pseudo‐cubic cell at the mixing composition x = 0.78 was also revealed. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compositional effects accompanying near equilibrium vapour growth of solid solution crystals of the types IV‐VI and II‐VI
Authors: Szczerbakow A. , Durose K.
Published: April 2010

Near equilibrium evaporation‐condensation in a sealed ampoule leads to almost full compositional reproduction of a solid solution if it consists of components having comparable vapour pressures; this can be qualitatively interpreted by domination of entropy increase. Nevertheless, even vestigial separation requires closer characteristics, since it may prove crucial – particularly for properties of semiconducting solid solutions. Maximum component separation allowed by a small temperature difference is described here in terms of thermodynamics and kinetics of solid‐vapour and vapour‐solid phase transitions. Theoretical models of the determining effects having different character are shortly described, and their applicability areas are determined. Experimental data collected for crystal growth of numerous semiconducting solid solutions of the II‐VI and IV‐VI type support the conclusion drawn from the models that the near equilibrium crystal growth from the vapour in a closed system ensures the highest degree of compositional uniformity. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Formation and ageing of L‐glutamic acid spherulites
Authors: Beck R. , Malthe‐Sørenssen D. , Andreassen J.‐P.
Published: April 2010

Polycrystalline spherulites of L‐glutamic acid have been crystallized by pH‐shift precipitation from stirred aqueous solutions. The time dependent behaviour of the spherulites has been studied during the crystallization process and batch filtration tests have been performed. It has been shown that the FBRM mean chord length of the investigated spherulites decreases in the course of time. The fact that the size reduction progresses faster at higher temperature and the solubility of resuspended polycrystalline particles decreasing with time, implies an ageing mechanism to be responsible for the observed changes in the particle size. It has been shown that the surface area decreases with time, ruling out particle breakage as a possible explanation for the decrease in particle size. XRD and Raman studies of L‐glutamic acid, however, show only marginal differences in the crystalline structure of particles obtained from different time stages. The ageing may occur due to several different mechanisms like phase transformation and Ostwald ripening. L‐glutamic acid spherulites after 3 h exhibit a 3‐fold higher value for the cake resistance as compared to particles after 0.5 h. However, particles obtained after 22 h exhibit an 8‐fold lower cake resistance as compared to the initially obtained spherulites, The increase in the cake resistance is attributed to the appearance of small plate‐like crystals and a change in the interaction between the crystal surface and the solution. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of zinc doping on pentaerythritol tetranitrate single crystals
Authors: Zhang G. , Bhattacharia S. K. , Weeks B. L.
Published: April 2010

In this study, the effect of zinc impurity on the organic high explosive pentaerythritol tetranitrate (PETN) single crystal has been investigated with optical microscopy and ex situ atomic force microscopy (AFM). The optical images show that the crystal shape has a transition with a predictable trend from long crystal to compact one as the zinc concentration is increased. Also, the 2‐dimentional (2‐D) growth hillocks are observed clearly on (110) face with contact AFM. The crystal growth occurs on monomolecular steps generated by 2‐D nucleation and followed by layer‐by‐layer expansion, and the macro‐steps formed onto the surface before spreading laterally as step bunches. The zinc ions are incorporated in growth steps as the zinc concentration is increased. The mechanism of inorganic impurity on molecular crystallization growth is still unclear. However, the incorporation of impurities may significantly affect growth kinetics of defect structure, and the bulk properties of molecular crystals. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Binding of mannose‐binding lectin to fructosamines: a potential link between hyperglycaemia and complement activation in diabetes
Authors: Fortpied Juliette , Vertommen Didier , Van Schaftingen Emile
Published: April 2010

Background

Complement activation via the MBL pathway has been proposed to play a role in the pathogenesis of diabetic complications. As protein glycation is increased in diabetes, we tested the possibility that the glycation product fructoselysine is a ligand for MBL and that its interaction with this protein may initiate complement activation.

Methods

We investigated the binding of MBL to fructoselysine by chromatography of human serum on fructoselysine‐Sepharose, followed by Western blot and mass spectrometry analysis. We also performed enzyme‐linked immunosorbent assays using purified MBL and fructoselysine‐derivatized (binding assay) or mannan‐coated plates (inhibition assay). Complement activation was determined by the fixation of C3d following incubation of fructoselysine‐derivatized plates with serum from subjects with different levels of MBL.

Results

MBL and its associated proteases were selectively purified from serum by chromatography on fructoselysine‐Sepharose. Competition experiments indicated that MBL had a similar affinity for mannose, fructose and fructoselysine. MBL bound, in a highly cooperative manner, to fructoselysine‐derivatized plates. This binding was associated with complement activation and was much lower with serum from subjects with low‐MBL genotypes.

Conclusions

MBL binding to fructoselysine and the ensuing complement activation may provide a physiopathological link between enhanced glycation and complement activation in diabetes. The cooperative character of this binding may explain the high sensitivity of diabetic complications to hyperglycaemia. Copyright © 2010 John Wiley & Sons, Ltd.
Different effects of pioglitazone and rosiglitazone on lipid metabolism in mouse cultured liver explants
Authors: Djaouti Louiza , Jourdan Tony , Demizieux Laurent , Chevrot Michaël , Gresti Joseph , Vergès Bruno , Degrace Pascal
Published: April 2010

Background

Pioglitazone (PIO) and rosiglitazone (ROSI) are widely used as oral antidiabetic agents for treatment of type 2 diabetes. Although these medications exert similar effects on blood glucose, recent clinical studies indicated that PIO has a more pronounced beneficial effect on lipid parameters than ROSI. In order to get further insight into the lipid effects of both drugs, we tested whether PIO, compared to ROSI, could exert direct effects on lipid liver metabolism in relation with plasma lipids.

Methods

We performedin vitrostudies using mice liver slices incubated 21 h either with ROSI (1 µmol/L) or PIO (7.5 µmol/L).

Results

We showed that both glitazones slightly reduced HMG‐CoA reductase mRNA levels at the same degree but only PIO reduced intracellular cholesterol content, suggesting an alteration of cholesterol uptake rather than an inhibition of cholesterol biosynthesis. This concept was supported by the reduction of scavenger receptor class B type I expression, hepatic lipase activity and high‐density lipoprotein cholesterol uptake in PIO‐treated liver explants. Conversely, hepatic lipase mRNA levels were increased 3.5‐fold. ROSI, but not PIO, induced acetyl‐CoA carboxylase and fatty acid synthase gene expression and increased apoB secretion suggesting a stimulation of lipogenesis. Concurrently, peroxisome proliferator‐activated receptor‐γ mRNA levels were induced by ROSI and not significantly changed by PIO. Besides, PIO appeared to be a more potent activator of AMP‐Activated Protein Kinase than ROSI.

Conclusions

PIO and ROSI exert specific direct effects on liver and extrapolating these data to humans could explain the significant improvements in plasma lipids observed in diabetic patients treated with PIO. Copyright © 2010 John Wiley & Sons, Ltd.
Candidate gene association study conditioning on individual ancestry in patients with type 2 diabetes and metabolic syndrome from Mexico City
Authors: Cruz M. , Valladares‐Salgado A. , Garcia‐Mena J. , Ross K. , Edwards M. , Angeles‐Martinez J. , Ortega‐Camarillo C. , Escobedo de la Peña J. , Burguete‐Garcia A. I. , Wacher‐Rodarte N. , Ambriz R. , Rivera R. , D'artote A. L. , Peralta J. , Parra Esteban J. , Kumate J.
Published: April 2010

Background

Type 2 diabetes (T2D) is influenced by diverse environmental and genetic risk factors. Metabolic syndrome (MS) increases the risk of cardiovascular disease and diabetes. We analysed 14 cases of polymorphisms located in 10 candidate loci, in a sample of patients with T2D and controls from Mexico City.

Methods

We analysed the association of 14 polymorphisms located within 10 genes (TCF7L2, ENPP1, ADRB3, KCNJ11, LEPR, PPARγ, FTO, CDKAL1, SIRT1 and HHEX) with T2D and MS. The analysis included 519 subjects with T2D defined according to the ADA criteria, 389 with MS defined according to the AHA/NHLBI criteria and 547 controls. Association was tested with the program ADMIXMAP including individual ancestry, age, sex, education and in some cases body mass index (BMI), in a logistic regression model.

Results

The two markers located within the TCF7L2 gene showed strong associations with T2D (rs7903146, T allele, odd ratio (OR) = 1.76, p = 0.001 and rs12255372, T allele, OR = 1.78, p = 0.002), but did not show significant association with MS. The non‐synonymous rs4994 polymorphism of the ADRB3 gene was associated with T2D (Trp allele, OR = 0.62, p = 0.001) and MS (Trp allele, OR = 0.74, p = 0.018). Nominally significant associations were also observed between T2D and the SIRT1 rs3758391 SNP and MS and the HHEX rs5015480 polymorphism.

Conclusions

Variants located within the gene TCF7L2 are strongly associated with T2D but not with MS, providing support to previous evidence indicating that polymorphisms at the TCF7L2 gene increase T2D risk. In contrast, the non‐synonymous ADRB3 rs4994 polymorphism is associated with T2D and MS. Copyright © 2010 John Wiley & Sons, Ltd.
Draxin is involved in the proper development of the dI3 interneuron in chick spinal cord
Authors: Su Yuhong , Zhang Sanbing , Islam Shahidul M. , Shinmyo Yohei , Naser Iftekhar Bin , Ahmed Giasuddin , Tanaka Hideaki
Published: April 2010

Generation of the appropriate types, numbers and distribution of neurons during the development of the nervous system requires the careful coordination of proliferation, differentiation, and patterning. In this work, we analyzed the roles of a repulsive axon guidance protein, draxin, on the development of chick spinal cord dI3 interneuron. draxin mRNA and/or protein were detected in the roof plate at first and then the boundary region between the ventricular and the mantle zones in chick spinal cord and dorsal basement membrane of the chick spinal cord. Overexpression of draxin caused the decreased and delayed migration of the dI3 interneuron, the reduction of progenitor cell proliferation, and abnormal localization of some ectopic progenitor‐like cells in the mantle zone of the spinal cord. Our data reveal that draxin may be involved in the proper development of the dI3 interneuron in chick spinal cord. Developmental Dynamics 239:1654–1663, 2010. © 2010 Wiley‐Liss, Inc.
Expression of the Lycat gene in the mouse cardiovascular and female reproductive systems
Authors: Wang Weidong , Ni Lujuan , Yu Qingming , Xiong Jingwei , Liu Hung‐Ching , Rosenwaks Zev
Published: April 2010

The Lycat homologue in zebrafish maps to the deletion interval of the cloche mutant in which hematopoietic and endothelial cell lineages are affected. However, its definitive relationship to cloche is inconclusive, partly due to inadequate expression data of Lycat from any organisms. We precisely examined the temporal and spatial expression patterns of Lycat in mouse using RNA in situ hybridization, immunostaining, and BAC transgenesis. Lycat is initially expressed in developing heart, lung, and somites, and later becomes progressively restricted to all vascular smooth muscle cells. In adult ovaries, Lycat turns on in oocytes during the transition from primary to secondary follicles. Expression of the Lycat/reporter transgene in the extraembryonic mesoderm, cardiogenic mesoderm, and primitive streak, but not extraembryonic endoderm at E7.5, suggests its potential roles in regulating cardiac, smooth muscle, hematopoietic and endothelial lineages. Promoter mapping assay by transient transgenesis identifies a novel cardiac‐specific regulatory region in the Lycat locus. Developmental Dynamics 239:1827–1837, 2010. © 2010 Wiley‐Liss, Inc.
Expression of the zebrafish CD133/prominin1 genes in cellular proliferation zones in the embryonic central nervous system and sensory organs
Authors: McGrail Maura , Batz Lindsey , Noack Kristin , Pandey Saumya , Huang Yong , Gu Xun , Essner Jeffrey J.
Published: April 2010

The CD133/prominin1 gene encodes a pentamembrane glycoprotein cell surface marker that is expressed in stem cells from neuroepithelial, hematopoietic, and various organ tissues. Here we report the analysis of two zebrafish CD133/prominin1 orthologues, prominin1a and prominin1b. The expression patterns of the zebrafish prominin1a and b genes were analyzed during embryogenesis using whole mount in situ hybridization. prominin1a and b show novel complementary and overlapping patterns of expression in proliferating zones in the developing sensory organs and central nervous system. The expression patterns suggest functional conservation of the zebrafish prominin1 genes. Initial analyses of prominin1a and b in neoplastic tissue show increased expression of both genes in a subpopulation of cells in malignant peripheral nerve sheath tumors in tp53 mutants. Based on these analyses, the zebrafish prominin1 genes will be useful markers for examining proliferating cell populations in adult organs, tissues, and tumors. Developmental Dynamics 239:1849–1857, 2010. © 2010 Wiley‐Liss, Inc.
Hydrogen Bonding in 2,3‐Dithiolatoterephthaldiamide Complexes of Cobalt(III), Nickel(II), and Iron(III)
Authors: Hahn F. Ekkehardt , Eiting Thomas , Seidel Wolfram W. , Pape Tania
Published: April 2010

The synthesis and characterization of the novel 2,3‐dithiolatoterephthaldiamide ligands C6H2{C(O)NHBn}2(SH)2 (H2‐1a)and C6H2{C(O)NH‐iPr}2(SH)2 (H2‐1b) as well as their complexes with NiII, CoIII, and FeIII is described. The molecular structures of the complexes (NEt4)[Co(1a)2], (AsPh4)2[Ni(1b)2]·dmf, and (AsPh4)[Fe(1a)2]·CH2Cl2 were determined by single‐crystal X‐ray diffraction. Electronic absorption spectroscopy and cyclic voltammetry were applied to investigate the electronic properties of the complex anions [M(L)2]n– (M = Ni, Co; L = 1a, 1b; n = 1, 2). Comparison of the structural and electronic characteristics of the complexes with ligands 1a2– and 1b2– to those of the corresponding complexes with related benzene‐o‐dithiolato ligands indicates a notable influence of intramolecular N–H···S hydrogen bonding between amide protons and coordinated sulfur atoms in 2,3‐dithiolatoterephthalamide complexes.
Bis‐Carbaborane‐Bridged Bis‐Glycophosphonates as Boron‐Rich Delivery Agents for BNCT
Authors: Stadlbauer Sven , Lönnecke Peter , Welzel Peter , Hey‐Hawkins Evamarie
Published: April 2010

The synthesis and properties of boron‐rich bis(meta‐carbaborane) derivatives containing glycophosphonate and glycophosphonothioate moieties are reported. All compounds are water‐soluble; however, the tetragalactosylated compounds show lower solubility than their disodium salts.
Size‐based separations as an important discriminator in development of proximity ligation assays for protein or organism detection
Authors: Leslie Daniel C. , Sohrabi Afshin , Ikonomi Pranvera , McKee Marian L. , Landers James P.
Published: April 2010

Proximity ligation is a powerful technique to measure minute concentrations of target protein with high specificity, and it has been demonstrated to be effective on a wide variety of protein targets. The proximity ligation assay (PLA) technique is shown to be compromised by the amplification of a nonspecific fluorescent product that is not indicative of protein presence, which was previously unidentified in a published procedure. This result illuminates the complexity of designing the optimal PLA and the possibility of using a size‐based separation to increase the reliability of PLAs in general. Nucleic acid controls were developed to optimize the assay, which led to a novel end‐point detection method that exploits microchip electrophoresis to size the products. This method provides a greater ability to distinguish a between the target protein's signal and noise in a PLA. The utility of the PLA is demonstrated by the detection of human pathogenic Escherichia coli O157:H7 bacteria, a pathogen at the root of many recent life‐threatening food poisoning outbreaks. The results of the PLA show a detection limit of 100 E. coli O157:H7 cells with minimal cross‐reactivity with gram positive control Staphylococcus aureus bacteria. The advantages of miniaturizing this process are the 100‐fold reduction in volume, greatly reducing reagent requirements, and doubling of the thermocycling speed via noncontact infrared heating. This work, consequently, adds to the understanding of background fluorescence in PLAs, provides a method for evaluating nonspecific amplification, and shows that a qualitative PCR response indicative of the presence protein can be achieved with PLA.
IsoGeometric Analysis: Stable elements for the 2D Stokes equation
Authors: Buffa A. , de Falco C. , Sangalli G.
Published: April 2010

In this paper, we discuss the application of IsoGeometric Analysis to incompressible viscous flow problems. We consider, as a prototype problem, the Stokes system and we propose various choices of compatible spline spaces for the approximations to the velocity and the pressure fields. The proposed choices can be viewed as extensions of the Taylor–Hood, Nédélec and Raviart–Thomas pairs of finite element spaces, respectively. We study the stability and convergence properties of each method and discuss the conservation properties of the discrete velocity field in each case. Copyright © 2010 John Wiley & Sons, Ltd.
Selective neck dissection in the management of the neck after (chemo)radiotherapy for advanced head and neck cancer. Proposal for a classification update
Authors: Hamoir Marc , Leemans C.René , Dolivet Gilles , Schmitz Sandra , Grégoire Vincent , Andry Guy
Published: April 2010

For patients with advanced regional disease, neck dissection following (chemo)radiotherapy remains controversial. Selective neck dissection (SND) was reported as suitable after chemoradiation in patients with advanced regional disease. Reduced morbidity represents the major advantage of SND. In a situation in which there is a major fibrosis around the previously invaded nodes, resection of 1 or more nonlymphatic structures may be required. The current classification of SND could be implemented by the addition of extended selective neck dissection (ESND). The standard basic procedures for SND spare the sternocleidomastoid muscle (SCM), the internal jugular vein (IJV), and the spinal accessory nerve (SAN). When an SND is associated with the resection of 1 or more nonlymphatic structures, it should be termed ESND. All additional nonlymphatic structure(s) removed should be identified in parentheses. The proposal to subclassify SND not only in accord with the resected lymph node levels but also upon the nonlymphatic structures removed may be of some help to avoid potential misinterpretation. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Obesity and Liver Cancer: A Key Role for Interleukin-6 and Signal Transducer and Activator of Transcription 3?
Authors: Roderburg Christoph , Trautwein Christian
Published: April 2010

Abstract

Epidemiological studies indicate that overweight and obesity are associated with increased cancer risk. To study how obesity augments cancer risk and development, we focused on hepatocellular carcinoma (HCC), the common form of liver cancer whose occurrence and progression are the most strongly affected by obesity among all cancers. We now demonstrate that either dietary or genetic obesity is a potent bona fide liver tumor promoter in mice. Obesity-promoted HCC development was dependent on enhanced production of the tumorpromoting cytokines IL-6 and TNF, which cause hepatic inflammation and activation of the oncogenic transcription factor STAT3. The chronic inflammatory response caused by obesity and enhanced production of IL-6 and TNF may also increase the risk of other cancers.
Hepatitis C Virus Infection in Living Color
Authors: Eyre Nicholas S. , Beard Michael R.
Published: April 2010

Abstract

Hepatitis C virus (HCV), which infects 2-3% of the world population, is a causative agent of chronic hepatitis and the leading indication for liver transplantation. The ability to propagate HCV in cell culture (HCVcc) is a relatively recent breakthrough and a key tool in the quest for specific antiviral therapeutics. Monitoring HCV infection in culture generally involves bulk population assays, use of genetically modified viruses and/or terminal processing of potentially precious samples. Here we develop a cell-based fluorescent reporter system that allows sensitive distinction of individual HCV-infected cells in live or fixed samples. We demonstrate use of this technology for several previously intractable applications, including live-cell imaging of viral propagation and host response, as well as visualizing infection of primary hepatocyte cultures. Integration of this reporter with modern image-based analysis methods could open new doors for HCV research.