bluuebunny/crossref_metadata_2025 huggingface dataset:
Rhodium(I)‐Catalyzed Intramolecular Carbonylative [2+2+1] Cycloaddition of Bis(allene)s: Bicyclo[6.3.0]undecadienones and Bicyclo[5.3.0]decadienones
Authors: Inagaki Fuyuhiko , Narita Syu , Hasegawa Takuma , Kitagaki Shinji , Mukai Chisato
Published: February 2009

No templates needed: The title reaction makes it easy to construct the bicyclo[6.3.0]undecadienone framework in high yields (see scheme). A template effect is not required to achieve this ring‐closing reaction efficiently. The present method can be applied to the construction of bicyclo[5.3.0] and bicyclo[4.3.0] ring systems. Ts=p‐toluenesulfonyl.

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Asymmetric Ring‐Closing Metathesis with a Twist
Authors: Klare Hendrik F. T. , Oestreich Martin
Published: February 2009

A double flip! The catalyst shown, with a molybdenum stereocenter and monodentate ligands (Si=SitBuMe2), promotes asymmetric ring‐closing metathesis of a broad range of substrates. Its unprecedented activity originates from its structural fluxionality, which enables double inversion at the metal center in the course of a single catalytic cycle. The catalyst passed the test in a metathesis reaction en route to (+)‐quebrachamine (see scheme).

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Influence of cleaning conditions on the degradation of recycled HDPE
Authors: Santana R. M. C. , Gondim G.
Published: February 2009

One of the materials most commonly found in municipal plastic waste (MPW) is High Density Polyethylene (HDPE), which is used particularly for food packaging and cleaning product containers. Postconsumer HDPE is generally contaminated with other impurities and, therefore, a cleaning process is necessary before it can be reprocessed. The aim of this study was to investigate the influence of the cleaning conditions on the oxidative degradation of postconsumer HDPE. These plastic materials were washed in NaOH solution, liquid detergent (D), and a mixture of NaOH/D (1 : 1). Results for the melt flow rate (MFR) and capillary rheometry showed that NaOH has a great influence on the oxidative degradation of HDPE. The HDPE treated with NaOH solution had a lower decomposition temperature, observed through Thermal Gravimetric (TG) analysis, and a lower the Oxidative Induction Time (OIT), obtained via Differential Scanning Calorimeter (DSC). Finally, the oxidative degradation of HDPE was verified through a higher carbonyl index. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and characterization of polysaccharide based graft copolymer by using potassium peroxymonosulphate/ascorbic acid as an efficient redox initiator in inert atmosphere
Authors: Kumar Rajesh , Srivastava Arti , Behari Kunj
Published: February 2009

Polysaccharide based graft copolymer (xanthan gum‐g‐4‐vinyl pyridine) was synthesized using potassium peroxymonosulphate/ascorbic acid redox initiator in inert atmosphere at 40°C. By studying the effect of the concentration of monomer, peroxymonosulphate (PMS), ascorbic acid (AA), xanthan gum (XOH), hydrogen ion along with effect of time and temperature on grafting characteristics: grafting ratio (%G), add on (%A), conversion (%C), efficiency (%E), homopolymer (%H), and rate of grafting (Rg), the reaction conditions for optimum grafting were determined. The optimum concentration of AA, H+ ion, 4‐VP for maximum grafting were found to be 10.0 × 10−3 mol dm−3, 2.5 × 10−2 mol dm−3, 10.0 × 10−3 mol dm−3, respectively. Maximum %G was obtained at minimum concentration of xanthan gum i.e., at 40.0 × 10−2 g dm−3 and at maximum concentration of PMS i.e., at 10.0 × 10−3 mol dm−3. The optimum temperature and time duration of reaction for maximum % of grafting were found to be 45°C and 120 min respectively. The synthesized graft copolymer was characterized by FTIR analysis. Thermogravimetric analysis showed that the xanthan gum‐g‐4‐vinyl pyridine is thermally more stable than pure gum. A probable mechanism was suggested for the graft copolymerization. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Influence of nanoclay and coupling agent on the physical and mechanical properties of polypropylene/bagasse nanocomposite
Authors: Nourbakhsh Amir , Ashori Alireza
Published: February 2009

In this work, the effects of nanoclay (1–4 wt %) and coupling agent (2 and 4 wt %) loading on the physical and mechanical properties of nanocomposites are investigated. Composites based on polypropylene (PP), bagasse flour, and nanoclay (montmorillonite type) was made by melt compounding and then compression molding. When 1–3 wt % nanoclay was added, the tensile properties increased significantly, but then decreased slightly as the nanoclay content increased to 4%. The impact strength was 6% lower by the addition of 1 wt % nanoclay, it was decreased further when the nanoclay content increased from 1 to 4%. Finally, the water absorption of PP/bagasse composites was lowered with the increase in nanoclay content. Additionally, the coupling agent, 4 wt % MAPP, improved the mechanical and physical properties of the composites more than the 2 wt % MAPP. From these results, we can conclude that addition of nanoclay enables to achieve better physical and mechanical properties in conventional composites. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Phenol–formaldehyde‐type resins made from phenol‐liquefied wood for the bonding of particleboard
Authors: Hassan El Barbary , Kim Moon , Wan Hui
Published: February 2009

Liquefaction of southern pine wood in phenol in 30–40 : 70–60 weight ratios resulted in homogeneous liquefied materials, which were directly used to synthesize phenol–formaldehyde (PF)‐type resins. The synthesized resins showed good physical and handling properties: low viscosity, stability for storage and transportation, and resin applicable by a common sprayer. Particleboard panels bonded with the synthesized resins showed promising physical properties and significantly lower formaldehyde emission values than those bonded with the urea–formaldehyde resin control. One deficiency observed for the synthesized resins was lower internal bond values, which might be overcome the use of a hot‐stacking procedure. Overall, the process of wood liquefaction with limited amounts of phenol as a solvent was shown to have the potential of providing practical, low‐cost PF‐type resins with very low formaldehyde emission potentials. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Characterization of PVAc/TiO2 hybrid nanofibers: From fibrous morphologies to molecular structures
Authors: Wu Ning , Shao Dongfeng , Wei Qufu , Cai Yibing , Gao Weidong
Published: February 2009

Polyvinyl acetate (PVAc)/titanium dioxide (TiO2) hybrid nanofibers were fabricated by combining sol–gel process with electrospinning technology, which consisted of PVAc as organic segment and TiO2 as inorganic part. The surface structures of the PVAc/TiO2 hybrid nanofibrous mats were examined using scanning electron microscopy (SEM). The surface morphology and bulk structures of single nanofiber were investigated by atomic force microscopy (AFM) and transmission electron microscopy (TEM). Fourier transform infrared spectroscopy (FTIR) was employed to analyze the chemical structures of the PVAc/TiO2 hybrid nanofibers. SEM scanning revealed that the fibrous structure was formed. AFM observations presented a significant difference in the morphology of the nanofibers before and after hybridization. It was observed from TEM images that some black streaks with various lengths distributed in a nanofiber. The FTIR analysis indicated the newly formed associated hydrogen bond because of the hybrid effect between PVAc and TiO2 sol. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis and thermal behavior of some brominated bismaleimides and polyaspartimides
Authors: Sava M.
Published: February 2009

Brominated bismaleimides were synthesized by the reaction of brominated bisphenols with 3‐ or 4‐maleimidobenzoyl chloride. The reaction of these maleimides with various aromatic diamines yielded brominated polyaspartimides. The monomers and polymers were characterized by Fourier transformed infrared and proton nuclear magnetic resonance spectroscopy. Thermal behavior of these brominated polyaspartimides was studied and compared with that of related polyaspartimides having other substituents instead of bromine or other bridges in the bisphenolic segment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Electrorheological characteristics of solvent‐cast polypyrrole/clay nanocomposite
Authors: Park D. P. , Lim S. T. , Lim J. Y. , Choi H. J. , Choi S. B.
Published: February 2009

A solvent‐casting method was applied to prepare intercalated polypyrrole (PPy)/organoclay nanocomposite for its electrorheological (ER) application under an applied electric field when dispersed in silicone oil. Soluble PPy was synthesized using sodium di(2‐ethylhexyl) sulfosuccinate (NaDEHS) as a doping agent at first, and its chemical structure and thermal property were examined using NMR and TGA, respectively. Insertion of the soluble PPy chain into an interlayer of the organoclay was confirmed by a X‐ray diffraction and its morphology was also examined by both SEM and TEM. Its ER property was examined under an applied electric field, regarding flow curve and universal yield stress. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Study of VLE phase behavior and correlating the thermophysical properties of polymer solutions using a local composition‐based model
Authors: Pazuki G. R. , Taghikhani V. , Vossoughi M.
Published: February 2009

In this study, the recently proposed model by Pazuki et al., based on the local composition concept (LCC), has been used in correlating the vapor–liquid phase behavior of polymer solutions. Similar to the LCC models available in the literature, the proposed model has two combinatorial and residual terms to account for both entropic as well as enthalpic effects in solution. The Flory‐Huggins model has been considered as the combinatorial part of the proposed model, while the equation proposed by Pazuki et al. was considered as the residual term. The proposed model has been used in correlating the vapor–liquid phase behavior for a large number of polymer–solvent mixtures at different conditions. The results obtained from the proposed model have been compared with those obtained from the UNIQUAC‐FV model. The results showed that the proposed model can accurately correlate the VLE data for polymer solutions studied in this work. Also, the proposed model has been used to obtain the thermophysical properties such as density, viscosity, and excess enthalpy for these polymer solutions. The results in connection with the thermophysical properties obtained from the proposed model have been compared with those obtained from the Poly‐NRTL and the Poly‐Wilson models. The results showed that the proposed model can accurately correlate the properties of polymer solutions at various conditions. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Development of novel tunable light scattering coating materials for fiber optic diffusers in photodynamic cancer therapy
Authors: Kostanski L. Kris , Pope Michael A. , Hrymak Andrew N. , Gallant Mark , Whittington William L. , Vesselov Leonid
Published: February 2009

To homogenize light emitted from fiber optic diffusers for photodynamic therapy (PDT), novel coating materials with tunable properties were designed. A class VI medical grade UV‐curable acrylic resin for biomedical applications was used for the polymer matrix, and titanium dioxide (TiO2) was added to the resin as a scattering agent. UV‐curability of coatings containing TiO2 was significantly influenced by the grade and surface treatment of the TiO2 studied. Despite using a free‐radical system without inert gas protection, all samples demonstrated considerable thermal postcuring. A novel TiO2 surface treatment methodology was developed based on unsaturated alkoxyorganosilanes combined with unsaturated carboxylic acids for compatibilizing TiO2 for use in the resin material studied. By adjusting the concentration of the surface‐modifying agent, the scattering efficiency and UV curability can be controlled by decreasing the effective particle size and enhancing the dispersibility of the powder filler within the resin. This modification will enable fine‐tuning of the effective size of TiO2 particles to the wavelength of laser light to be scattered to maximize scattering efficiency in photodynamic cancer therapy and possibly also in other forms of cancer treatment (interstitial laser hyperthermia or interstitial laser photocoagulation). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation of chitosan‐based thermosensitive hydrogels for drug delivery
Authors: Zhou Hui Yun , Chen Xi Guang , Kong Ming , Liu Cheng Sheng
Published: February 2009

The thermosensitive material that could be transformed into gel at 37°C was prepared from chitosan (dissolved in acetic acid/sodium acetate buffer solution) and a mixture of α‐ and β‐glycerophosphate (αβ‐GP). The thermosensitive characteristics, appearance, and structure of the hydrogel were all affected by the pH, ionic strength, and CS/αβ‐GP ratio. The optimal conditions for the preparation of a transparent CS‐αβ‐GP thermosensitive hydrogel were pH 4.6, ionic strength 0.15 mol/L, and a CS/αβ‐GP ratio of 8.8/1.2 (v/v). The hydrogel was stable for at least 3 months at 4°C. We believe that hydrogen bonding interactions between the NH (and CO) groups of chitosan and the OH groups of αβ‐GP play an important role during the process of sol‐to‐gel transition. The cumulative release of adriamycin from the CS‐αβ‐GP hydrogel, measured in PBS at pH 7.4, reached only 60 to 70% over 24 h, indicating that this material could be potentially used in a sustained drug delivery system. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The water vapor sorption behavior of natural fibers
Authors: Hill Callum A. S. , Norton Andrew , Newman Gary
Published: February 2009

The water vapor sorption behavior of a range of natural fibers (jute, flax, coir, cotton, hemp, Sitka spruce) has been studied. The data were analyzed using the Hailwood Horrobin model for isotherm fitting and determination of monolayer moisture content. The Hailwood Horrobin model was found to provide good fits to the experimental data. The extent of hysteresis exhibited between the adsorption and desorption isotherms was dependent on fiber type studied and was larger with high lignin compared with low lignin content fibers. The area bounded by the hysteresis loop decreased as the isotherms were performed at progressively higher temperatures. This behavior is consistent with sorption interactions occurring with a glassy solid below the glass transition temperature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Insect chymotrypsins: chloromethyl ketone inactivation and substrate specificity relative to possible coevolutional adaptation of insects and plants
Authors: Lopes Adriana R. , Sato Paloma M. , Terra Walter R.
Published: February 2009

Insect digestive chymotrypsins are present in a large variety of insect orders but their substrate specificity still remains unclear. Four insect chymotrypsins from 3 different insect orders (Dictyoptera, Coleoptera, and two Lepidoptera) were isolated using affinity chromatography. Enzymes presented molecular masses in the range of 20 to 31 kDa and pH optima in the range of 7.5 to 10.0. Kinetic characterization using different colorimetric and fluorescent substrates indicated that insect chymotrypsins differ from bovine chymotrypsin in their primary specificity toward small substrates (like N‐benzoyl‐L‐Tyr p‐nitroanilide) rather than on their preference for large substrates (exemplified by Succynil‐Ala‐Ala‐Pro‐Phe p‐nitroanilide). Chloromethyl ketones (TPCK, N‐ α‐tosyl‐L‐Phe chloromethyl ketone and Z‐GGF‐CK, N‐ carbobenzoxy‐Gly‐Gly‐Phe‐CK) inactivated all chymotrypsins tested. Inactivation rates follow apparent first‐order kinetics with variable second order rates (TPCK, 42 to 130 M−1 s−1; Z‐GGF‐CK, 150 to 450 M−1 s−1) that may be remarkably low for S. frugiperda chymotrypsin (TPCK, 6 M−1 s−1; Z‐GGF‐CK, 6.1 M−1 s−1). Homology modelling and sequence alignment showed that in lepidopteran chymotrypsins, differences in the amino acid residues in the neighborhood of the catalytic His 57 may affect its pKa value. This is proposed as the cause of the decrease in His 57 reactivity toward chloromethyl ketones. Such amino acid replacement in the active site is proposed to be an adaptation to the presence of dietary ketones. © 2009 Wiley Periodicals, Inc.
Optimal investment problem with stochastic interest rate and stochastic volatility: Maximizing a power utility
Authors: Li Jinzhu , Wu Rong
Published: February 2009

In this paper, we assume that an investor can invest his/her wealth in a bond and a stock. In our wealth model, the stochastic interest rate is described by a Cox–Ingersoll–Ross (CIR) model, and the volatility of the stock is proportional to another CIR process. We obtain a closed‐form expression of the optimal policy that maximizes a power utility. Moreover, a verification theorem without the usual Lipschitz assumptions is proved, and the relationships between the optimal policy and various parameters are given. Copyright © 2009 John Wiley & Sons, Ltd.
Inference Based on Kernel Estimates of the Relative Risk Function in Geographical Epidemiology
Authors: Hazelton Martin L. , Davies Tilman M.
Published: February 2009

Kernel smoothing is a popular approach to estimating relative risk surfaces from data on the locations of cases and controls in geographical epidemiology. The interpretation of such surfaces is facilitated by plotting of tolerance contours which highlight areas where the risk is sufficiently high to reject the null hypothesis of unit relative risk. Previously it has been recommended that these tolerance intervals be calculated using Monte Carlo randomization tests. We examine a computationally cheap alternative whereby the tolerance intervals are derived from asymptotic theory. We also examine the performance of global tests of hetereogeneous risk employing statistics based on kernel risk surfaces, paying particular attention to the choice of smoothing parameters on test power (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Re‐Formulating Non‐inferiority Trials as Superiority Trials: The Case of Binary Outcomes
Authors: Durkalski Valerie L. , Berger Vance W.
Published: February 2009

Non‐inferiority trials are conducted for a variety of reasons including to show that a new treatment has a negligible reduction in efficacy or safety when compared to the current standard treatment, or a more complex setting of showing that a new treatment has a negligible reduction in efficacy when compared to the current standard yet is superior in terms of other treatment characteristics. The latter reason for conducting a non‐inferiority trial presents the challenge of deciding on a balance between a suitable reduction in efficacy, known as the non‐inferiority margin, in return for a gain in other important treatment characteristics/findings. It would be ideal to alleviate the dilemma on the choice of margin in this setting by reverting to a traditional superiority trial design where a single p ‐value for superiority of both the most important endpoint (efficacy) and the most important finding (treatment characteristic) is provided. We discuss how this can be done using the information‐preserving composite endpoint (IPCE) approach and consider binary outcome cases in which the combination of efficacy and treatment characteristics, but not one itself, paints a clear picture that the novel treatment is superior to the active control (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of Penalized Splines in Analyzing Neuronal Data
Authors: Maringwa John T. , Faes Christel , Geys Helena , Molenberghs Geert , Cadarso‐Suárez Carmen , Pardo‐Vázquez José L. , Leborán Víctor , Acunña Carlos
Published: February 2009

Neuron experiments produce high‐dimensional data structures. Therefore, application of smoothing techniques in the analysis of neuronal data from electrophysiological experiments has received considerable attention of late. We investigate the use of penalized splines in the analysis of neuronal data. This is first illustrated when interested in the temporal trend of a single neuron. An approach to investigate the maximal firing rate, based on the penalizedspline model is proposed. Determination of the time of maximal firing rate is based on non‐linear optimization of the objective function with the corresponding confidence intervals constructed based on the first‐order derivative function. To distinguish between the curves from different experimental conditions in a moment‐by‐moment sense, bias adjusted simulation‐based simultaneous confidence bands leading to global inference in the time domain are constructed. The bands are an extension of the approach proposed by Ruppert et al. (2003). These methods are in a second step extended towards the analysis of a population of neurons via a marginal or population‐averaged model (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Application of plant tissue cultures in phytoremediation research: Incentives and limitations
Authors: Doran Pauline M.
Published: February 2009

The aim of this review is to critically assess the benefits and limitations associated with the use of in vitro plant cell and organ cultures as research tools in phytoremediation studies. Plant tissue cultures such as callus, cell suspensions, and hairy roots are applied frequently in phytoremediation research as model plant systems. In vitro cultures offer a range of experimental advantages in studies aimed at examining the intrinsic metabolic capabilities of plant cells and their capacity for toxicity tolerance. The ability to identify the contributions of plant cells to pollutant uptake and detoxification without interference from microorganisms is of particular significance in the search for fundamental knowledge about plants. However, if the ultimate goal of plant tissue culture experiments is the development of practical phytoremediation technology, the limitations inherent in the use of in vitro cultures as a representative of whole plants in the field must be recognized. The bioavailability of contaminants and the processes of pollutant uptake and metabolite distribution are likely to be substantially different in the two systems; this can lead to qualitative as well as quantitative differences in metabolic profiles and tolerance characteristics. Yet, many studies have demonstrated that plant tissue cultures are an extremely valuable tool in phytoremediation research. The results derived from tissue cultures can be used to predict the responses of plants to environmental contaminants, and to improve the design and thus reduce the cost of subsequent conventional whole plant experiments. Biotechnol. Bioeng. 2009;103: 60–76.
Inhibition of succinic acid production in metabolically engineered Escherichia coli by neutralizing agent, organic acids, and osmolarity
Authors: Andersson Christian , Helmerius Jonas , Hodge David , Berglund Kris A. , Rova Ulrika
Published: February 2009

The economical viability of biochemical succinic acid production is a result of many processing parameters including final succinic acid concentration, recovery of succinate, and the volumetric productivity. Maintaining volumetric productivities >2.5 g L−1 h−1 is important if production of succinic acid from renewable resources should be competitive. In this work, the effects of organic acids, osmolarity, and neutralizing agent (NH4OH, KOH, NaOH, K2CO3, and Na2CO3) on the fermentative succinic acid production by Escherichia coli AFP184 were investigated. The highest concentration of succinic acid, 77 g L−1, was obtained with Na2CO3. In general, irrespective of the base used, succinic acid productivity per viable cell was significantly reduced as the concentration of the produced acid increased. Increased osmolarity resulting from base addition during succinate production only marginally affected the productivity per viable cell. Addition of the osmoprotectant glycine betaine to cultures resulted in an increased aerobic growth rate and anaerobic glucose consumption rate, but decreased succinic acid yield. When using NH4OH productivity completely ceased at a succinic acid concentration of ∼40 g L−1. Volumetric productivities remained at 2.5 g L−1 h−1 for up to 10 h longer when K‐ or Na‐bases where used instead of NH4OH. The decrease in cellular succinic acid productivity observed during the anaerobic phase was found to be due to increased organic acid concentrations rather than medium osmolarity. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Development and Biological Evaluation of a Novel Aurora A Kinase Inhibitor
Authors: Sardon Teresa , Cottin Thomas , Xu Jing , Giannis Athanassios , Vernos Isabelle
Published: February 2009

Stop dividing: In the quest for antitumorigenic compounds, aurora A kinase has recently emerged as a potential drug target. In this paper three novel aurora inhibitors (shown in the illustration) have been tested for their biological activity in cultured cells. One of them (TC‐28) appears to be a promising specific aurora A inhibitor in vivo.

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The aurora kinase family groups several serine/threonine kinases with key regulatory functions during cell division. The three mammalian members, aurora A, B and C, are frequently over‐expressed in human tumors and the aurora A gene is located in a genomic region frequently amplified in breast and colon cancer. All these data have fuelled the idea that aurora kinases are promising targets for anticancer therapy. Indeed some inhibitory compounds are currently being evaluated in clinical trials. However, it was recently shown that mutations in the targeted kinase can confer resistance to a broad range of inhibitors and render patients resistant to treatments. Moreover, aurora A over‐expression results in increased resistance to antimitotic agents. The development of new compounds targeting aurora A is therefore highly relevant. We describe here the synthesis of three novel aurora kinase inhibitors, TC‐28, TC‐34 and TC‐107. We report their properties as aurora inhibitors in vitro and their effect on human tissue culture cell lines. Interestingly, our results show that TC‐28 has properties compatible with the specific inhibition of aurora A, in vivo.
Photogenerated Quinone Methides as Protein Affinity Labeling Reagents
Authors: Jiang Jiangsong , Zeng Dexing , Li Shuwei
Published: February 2009

Highly specific protein labeling: Photogenerated quinine methides (QMs) can act as highly specific light‐controllable protein affinity labeling reagents, broadening their applications to the study of protein–ligand and protein–protein interactions. The reactions between QMs and nucleophiles are less heterogeneous than those of other photogenerated active intermediates such as carbenes and nitrenes, making it easier to identify labeled species.

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Cover Picture: Assessing Carbohydrate–Carbohydrate Interactions by NMR Spectroscopy: The Trisaccharide Epitope from the Marine Sponge Microciona prolifera (ChemBioChem 3/2009)
Authors: Santos J. Ignacio , Carvalho de Souza Adriana , Cañada F. Javier , Martín‐Santamaría Sonsoles , Kamerling Johannis P. , Jiménez‐Barbero Jesús
Published: February 2009

The cover picture shows a 3D model, derived from molecular dynamics simulations, of the trisaccharides that result from the mutual interaction in solution of the synthetically prepared trisaccharide epitope of the marine sponge Microciona prolifera and gold glyconanoparticles, displaying the same sugar moiety, in the presence of calcium. As can be seen, the trisaccharides are gathered together by bridged calcium atoms, thus precluding the dissociation of the complex. The different trisaccharide entities interact in a parallel fashion and are layered in pairs. Thus, they show a segmental type of interaction that could explain the actual interaction in Nature of the native g‐200 acidic glycan present in the MAFp3 glycoprotein, with the polysaccharide–polysaccharide interaction taking place via the trisaccharide epitopes. For further details, see the article by J. Kamerling, J. Jiménez‐Barbero et al. on p. 511 ff. The picture of Microciona prolifera was taken from http://www.uniprot.org/taxonomy/27928

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EPR Spectroscopy of a Family of CrIII7MII (M = Cd, Zn, Mn, Ni) “Wheels”: Studies of Isostructural Compounds with Different Spin Ground States
Authors: Piligkos Stergios , Weihe Høgni , Bill Eckhard , Neese Frank , El Mkami Hassane , Smith Graham M. , Collison David , Rajaraman Gopalan , Timco Grigore A. , Winpenny Richard E. P. , McInnes Eric J. L.
Published: February 2009

Spinning wheels: The presented highly resolved multifrequency continuous wave EPR spectra (e.g., see figure) of the heterooctametalic “wheels” Cr7M provide rare examples of high nuclearity polymetallic systems where detailed information on the spin‐Hamiltonian parameters of the ground and excited spin states is observed.

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We present highly resolved multifrequency (X‐, K‐, Q‐ and W‐band) continous wave EPR spectra of the heterooctametalic “wheels”, [(CH3)2NH2][CrIII7MIIF8((CH3)3CCOO)16], hereafter Cr7M, where M=Cd, Zn, Mn, and Ni. These experimental spectra provide rare examples of high nuclearity polymetallic systems where detailed information on the spin‐Hamiltonian parameters of the ground and excited spin states is observed. We interpret the EPR spectra by use of restricted size effective subspaces obtained by the rigorous solution of spin‐Hamiltonians of dimension up to 105 by use of the Davidson algorithm. We show that transferability of spin‐Hamiltonian parameters across complexes of the Cr7M family is possible and that the spin‐Hamiltonian parameters of Cr7M do not have sharply defined values, but are rather distributed around a mean value.
Enhanced Electron‐Transfer Properties of Cofacial Porphyrin Dimers through π–π Interactions
Authors: Takai Atsuro , Gros Claude P. , Barbe Jean‐Michel , Guilard Roger , Fukuzumi Shunichi
Published: February 2009

π–π assisted: Photoinduced electron transfer from cofacial porphyrin dimers to electron acceptors is prominently accelerated, whereas the back electron transfer is decelerated, relative to the corresponding porphyrin monomer (see figure).

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The radical cation of zinc tetrapentylporphyrin is dimerized with an excess of the neutral counterpart to form the dimer radical cation in which the unpaired electron is delocalized over both porphyrin rings. The dimeric radical cation exhibits an NIR absorption spectrum characteristic of weak π‐bond formation between the porphyrin rings. When cofacial porphyrin dimers, linked by different spacers, are oxidized such π‐bond formation between the porphyrin rings is also recognized in cyclic voltammetry, and Vis/NIR and ESR spectroscopic measurements. The dynamics of photoinduced electron transfer from the triplet excited states of cofacial porphyrin dimers to a series of electron acceptors were investigated by using laser flash photolysis measurements and compared with the porphyrin monomer. The rates of photoinduced electron‐transfer reactions of cofacial porphyrin dimers are prominently accelerated compared with the reference monomer. The driving‐force dependence of the rate constants of photoinduced electron‐transfer reactions was analyzed in light of the Marcus theory of electron transfer to afford the reorganization energies of electron transfer (λ). The λ values of cofacial porphyrin dimers are significantly smaller than those of the porphyrin monomer when compared at the same driving force of the photoinduced electron transfer. The λ values increase linearly with an increase in the driving force of the photoinduced electron transfer. This is accompanied by an increase in the distance between electron donor and acceptor molecules, where the electron transfer occurs. The enhanced electron‐transfer properties of cofacial porphyrin dimers, in relation with the important role of the special pair in the photosynthetic reaction center, result from the smaller reorganization energy (λ) together with the larger driving force of the photoinduced electron transfer due to the π‐electron delocalization in the dimer radical cations.
Energetic Ethylene‐ and Propylene‐Bridged Bis(nitroiminotetrazolate) Salts
Authors: Joo Young‐Hyuk , Shreeve Jean'ne M.
Published: February 2009

High energy density materials with ethylene‐ and propylene bis(5‐nitroiminotetrazolate) as the anions are reported; all salts were fully characterized by IR, and 1H, 13C, and 15N NMR spectroscopy as well as elemental analyses. In addition, the heats of formation (ΔHf) and the detonation pressures (P) and velocities (D) were calculated.

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The synthesis and detonation properties of high energy density materials with ethylene‐ and propylene bis(nitroiminotetrazolate) as the anions are reported; all salts were fully characterized by IR, and 1H, 13C, and 15N NMR spectroscopy as well as elemental analyses. In addition, the heats of formation (ΔHf) were calculated with the Gaussian 3.0 suite of programs. By using the experimental values for the densities of the nitroiminotetrazolate salts, the detonation pressures (P) and velocities (D) were calculated using Cheetah 5.0.
Cover Picture: Size Selection During Crystallization of Oppositely Charged Nanoparticles (Chem. Eur. J. 9/2009)
Authors: Kowalczyk Bartlomiej , Kalsin Alexander M. , Orlik Rafal , Bishop Kyle J. M. , Patashinskii Alexander Z. , Mitus Antoni , Grzybowski Bartosz A.
Published: February 2009

Oppositely charged nanoparticles characterized by different size distributions can form 3D supracrystals. In their Communication on page 2032 ff., Grzybowski et al. come to the conclusion that, from both the experimental data and the simulations, the growth of 3D crystals is hindered by entropic effects, owing to finite nanoparticle polydispersities.

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Two‐Dimensional echocardiographic evaluation of the severity of mitral stenosis with reference to the prediction for mitral valve commissurotomy or replacement
Authors: Okamura K. , Fukuda I. , Maeta H. , Mitsui T. , Hori M.
Published: February 2009

Thirty patients with mitral stenosis were classified into three grades of severity reflected by anterior mitral leaflet and subvalvular apparatus using two‐dimensional echocardiography in order to study the possibility of predicting the type of surgery indicated, and were evaluated pre‐ and postoperatively for systolic and diastolic volumes; left heart function using left ventricular posterior wall movement (LVPWVsmax, LVPWVdmax) and posterior wall excursion (PWE) and newly devised left atrial empty volume ratio (LAEVR). The LVPWVsmax was increased from 57±7 to 74±7 mm/s (p<0.001) in grade I, from 48±13 to 63±9 mm/s (p<0.02) in grade II, and from 44±6 to 64±7 mm/s (p<0.001) in grade III. The LVPWVdmax showed an increase from 68±15 to 91 ± 15 mm/s (p<0.001) in grade I, from 57±17 to 86±18 mm/s (p<0.01) in grade II, and from 55±11 to 83±6 mm/s (p<0.01) in grade III. In the PWE, there was an improvement from 12.4±1.6 to 15.5±2.1 mm (p<0.01) in grade I; from 10.5±2.0 to 12.5 ± 1.5 mm (p<0.02) in grade II; and from 9.4±1.5 to 14.4 ± 1.5 mm (p<0.001) in grade III. In the LAEVR, there was also an improvement from 65 ± 12 to 39±21% (p<0.01) in grade I; from 53±13 to 51 ± 12% in grade II; and from 67±15 to 32±18% (p<0.001) in grade III. From these results, it may be concluded that even in cases with dome formation of the anterior mitral leaflet by two‐dimensional echocardiography, when a half or more of leaflet and subvalvular apparatus are thickened, it is difficult to obtain good valvular and left heart function by open mitral commissurotomy and suggests recommendation of mitral valve replacement in grade II and III cases.
Significance of collateral circulation on peri‐infarct zone: Assessment with stress thallium‐201 scintigraphy
Authors: Imamura T. , Araki H. , Fukuyama T. , Maruoka Y. , Ootsubo H. , Nakamura M. , Koiwaya Y. , Tanaka K.
Published: February 2009

To evaluate the significance of collateral circulation on peri‐infarct zone, stress myocardial scintigraphy and contrast left ventriculography (LVG) were performed in 38 patients with recent myocardial infarction (MI). All patients had at least one completely occluded coronary artery corresponding to the infarct area. In patients with good collaterals, stress induced transient enlargement of the perfusion defect, however, in those with poor or no collaterals the enlargement did not occur (p>0.05). Wall motion abnormality on LVG was significantly milder in the former patients than in the latter (p>0.001). Transient enlargement of the perfusion defect after stress and milder left ventricular asynergy were more frequently observed in patients with anterior MI and good collaterals. These observations indicate that good collaterals may keep some myocardium in the peri‐infarct zone viable.
Intravenous diltiazem for the treatment of supraventricular tachycardia
Authors: Sternbach G. L. , Schroeder J. S. , Eliastam M. , Beier‐Scott L.
Published: February 2009

To determine the effects of diltiazem hydrochloride on patients with paroxysmal supraventricular tachycardia, we administered intravenous diltiazem, 0.25 mg/kg to patients who presented to the Stanford Medical Center Emergency Department with this rhythm. Blood pressure was recorded prior to administration, and monitored for 20 min thereafter. Six of the ten patients converted to sinus rhythm a mean of 7.75 min (±4.4) after drug administration. The remaining four experienced slowing of heart rates from a mean of 177 to 166 beats/min. Systolic blood pressure fell a mean of 12.4 mmHg during treatment, but returned to pretreatment level or higher within 20 min following diltiazem administration. This mean degree of blood pressure reduction compares favorably with effects produced by intravenous verapamil under comparable circumstances. Intravenous diltiazem appears to be a safe and effective drug for the conversion of paroxysmal supraventricular tachycardia.
Transient global amnesia after coronary angiography
Authors: Koehler P. J. , Endtz L. J. , DenB AKKER P. B.
Published: February 2009

A 69‐year‐old woman suffered transient global amnesia as a complication following coronary angiography. Three reports have been described earlier. The etiology of this condition is discussed. Possibly, this complication is overlooked in some cases.
Comparative analysis of myocardial enzyme activities of the energy‐supplying metabolism in patients with dilative cardiomyopathies and valve diseases
Authors: Klein H. H. , Spaar U. , Schlepple H. , Wiegand V. , Kreuzer H.
Published: February 2009

We determined representative enzyme activities of glycogenolysis (glycogen phosphorylase) glycolysis (d‐glyceraldehyde‐3‐phosphate dehydrogenase, GAPDH), β oxidation of free fatty acids (1‐3‐hydroxyacyl CoA dehydrogenase, HADH), citric acid cycle (citrate synthase, CS), lactate fermentation (lactate dehydrogenase LDH), and creatine phosphate metabolism (creatine kinase, CK) in left ventricular samples of 36 patients to investigate if the metabolic capacities of the energysupplying pathways are differently affected in different heart diseases. There were 17 patients with mitral valve diseases (MVD), 8 patients with aortic valve diseases (AVD), and 11 patients who suffered from dilative cardiomyopathies (DCM). The main metabolic characteristic on the level of enzymatic organization in patients with DCM was an increased ratio of GAPDH/HADH activities and a decreased ratio of HADH/CS activities compared to the valve‐diseased patients. This result indicates that the capacity of glucose oxidation is enhanced at the expense of fatty acid metabolism in patients with DCM. Furthermore, we determined significantly lower myocardial CK activities in this group of patients, most probably reflecting a diminished content of myofibrils. Citrate synthase activity was lowest in patients with AVD. Although we cannot rule out that the impaired left ventricular function is in part responsible for the shift of the capacities of the energy‐supplying metabolism in patients with DCM, we favor the assumption that it is a specific feature of this myocardial disease.
Probable early acute hepatitis with parenteral amiodarone
Authors: Lupon‐Rosés J. , SimÓa‐Canonge R. , Lu‐Cortez L. , Permanyer‐Miralda G. , Allende‐Monclús H.
Published: February 2009

A patient with acute changes suggesting acute hepatitis after parenteral amiodarone administration is described. A 77‐year‐old man with previous myocardial infarction was admitted with chronic left heart failure and atrial tachycardia. Initial hepatic function tests were strictly normal. After therapy with parenteral amiodarone (2300 mg in 3 days) and other measures, signs of congestive heart failure disappeared; subsequently the patient developed jaundice, marked increase in serum transaminase levels and fall in prothrombin time, and histologic changes of severe centrilobular necrosis were observed in hepatic biopsy. Clinical, laboratory (absence of others markers of hepatic disease), and histological findings seem to rule out common causes of hepatic disease. Therefore, parenteral amiodarone was implicated as the cause of acute hepatitis in this patient. In addition, there were findings suggesting a possibly immunologically mediated mechanism.
The current status of ablation of cardiac conduction tissue and ectopic myocardial foci by transvenous electrical discharges
Authors: Ward D. E. , Camm A. J.
Published: February 2009

Ablation of AV nodal/His bundle conduction by fulgurative electrical discharges has revolutionized the management of refractory supraventricular tachycardias of any type which requires AV conduction over the normal anatomical pathways. The success and safety of the technique is such that it has eclipsed operative ablation of AV conduction. It is increasingly clear that both anomalous pathway conduction and ventricular tachycardia foci may be destroyed by the technique of fulguration and preliminary evidence suggests that certain types of atrial foci may also be susceptible to this method of ablation. Development of purpose‐designed electrodes for delivery of the discharges is likely to reduce maximum energy requirements and increase the safety of fulguration.
Acute and chronic effects of nicardipine on systolic and diastolic left ventricular performance in patients with heart failure: A pilot study
Authors: Lahiri A. , Robinson C. W. , Kohli R. S. , Caruana M. P. , Raftery E. B.
Published: February 2009

Nicardipine is a new calcium ion antagonist with vasodilating properties which has been shown to be effective in the treatment of hypertension and angina. We have studied its effect on systolic and diastolic left ventricular function in patients with mild to moderate degrees of congestive heart failure. Ten male patients with New York Heart Association Class II and III heart failure underwent acute treatment with an intravenous infusion of nicardipine (10 mg over 10 minutes). A nuclear probe was used to monitor left ventricular ejection fraction, peak filling rate, and relative cardiac output. Blood pressure and heart rate were also measured. The blood pressure (mean±SD) fell from 133±26/86±11 mmHg to 103±22/69±13; the heart rate rose from 67±9 beats/min to 85±10; left ventricular ejection fraction from 31±7 to 38±6%; relative cardiac output from 24±9 to 41±11; peak filling rate from 1.18±0.4 end‐diastolic volume per second to 1.82±0.4 (p<0.001 in all cases) at the end of infusion. After 4 weeks of chronic treatment in eight patients (20 mg to be taken three times daily (tds) in one and 40 mg tds in 7), the blood pressure and heart rate had returned to baseline values but the improvements in left ventricular ejection fraction, relative cardiac output, and peak filling rate were sustained; this was associated with functional improvement in all 8 patients. This preliminary study suggests that nicardipine has a potent vasodilator effect and produces significant objective improvement in left ventricular function, without producing any negative ionotropic effects. Further studies are required to confirm these effects in a wider range of patients with heart failure.
Amiodarone: An effective alternative for recalcitrant supraventricular and ventricular tachycardias
Authors: Best J. F. , Rinkenberger R. , Lynch L. , Dunn M.
Published: February 2009

Amiodarone was used in the treatment of 21 patients with supraventricular or ventricular arrhythmias which were refractory to conventional antiarrhythmic drugs, individually or in combination. Six of seven patients with supraventricular arrhythmias and 12 of 14 with ventricular tachycardia were controlled with amiodarone. Although side effects were common, only one patient was removed from treatment due to pulmonary fibrosis. We conclude that amiodarone is an effective antiarrhythmic drug for refractory ventricular and supraventricular arrhythmias.
The long‐term outcome of patients who suffered and survived an acute myocardial infarction in the midst of recurrent attacks of variant angina
Authors: Madias J. E.
Published: February 2009

Twenty‐one patients, ranging in age between 28 and 59 years, who survived hospitalization for an acute myocardial infarction in association with repetitive attacks of variant angina, were followed prospectively for 59.1±5.1 (SEM) (range 17–120) months. Four patients died, one of sudden death 17 months after admission, one of congestive heart failure at 33 months, and two of cancer at 43 and 45 months of follow‐up. Three patients had four new myocardial infarctions at 22, 32, 33, and 61 months of follow‐up. Six patients were readmitted for angina or other cardiac reasons. Twelve patients remained asymptomatic throughout the follow‐up and one more patient was asymptomatic before and after his recurrent myocardial infarction. No relapse of variant angina was documented. Thus, the long‐term course of patients with variant angina culminating in acute myocardial infarction is relatively benign, despite the highly unstable features of their initial presentation.
Effect of nifedipine on dipyridamole thallium‐201 myocardial scintigraphy
Authors: Bonaduce D. , Morgano G. , Canonico V. , Breglio R. , Condorelli M. , Salvatore M. , Muto P.
Published: February 2009

The effect of a calcium antagonist drug, nifedipine, on dipyridamole thallium‐201 images was assessed in 10 angina patients with positive dipyridamole test. Two dipyridamole thallium‐201 tests were performed, the first in basal conditions, the second after administration of 20 mg nifedipine. After dipyridamole, heart rate and double product increased respectively from 68.0±8.2 to 94.7±11.5 beats/min (p<0.01) and from 9459.5±1800.2 to 12,770.0±1864.7 mmHg x beats/min (p<0.01). Dipyridamole when infused after nifedipine induced an increase in heart rate from 74.2±7.16 to 88.8±5.6 beats/min (p<0.01) and in double product from 9650.5±1348.0 to 11,399.0±1146 mmHg x beats/min (p<0.05). Systolic and diastolic blood pressures were unmodified during the two studies. Segment scores were comparable before and after nifedipine. Thus, nifedipine does not worsen thallium‐201 myocardial images obtained during dipyridamole infusion, therefore, this test could provide an alternative to exercise thallium‐201 in patients receiving calcium antagonist drugs.