bluuebunny/crossref_metadata_2025_split huggingface dataset:
Differential involvement of TLR2 and TLR4 in host survival during pulmonary infection with Chlamydia pneumoniae
Authors: Rodriguez Nuria , Wantia Nina , Fend Falko , Dürr Susanne , Wagner Hermann , Miethke Thomas 
Published: April 2006

AbstractThe relevance of TLR2 and TLR4 for recognizing Chlamydia pneumoniae in vivo during pulmonary infection and to survive the infection was explored. We found that early immune responses triggered by C. pneumoniae partially depended on TLR2, but not on TLR4. The chemokines MIP‐2 and MIP‐1α were not induced, while IL‐12p40 levels were higher in TLR2–/– mice compared to wild‐type mice. Secretion of TNF, keratinocyte‐derived chemokine and monocyte chemoattractant protein‐1 was attenuated in TLR2–/– mice, while IFN‐γ was increased as in wild‐type mice. The pulmonary cyto‐ and chemokine response of TLR2–/–×TLR4d/d was similar to TLR2–/– mice. TLR2–/– and TLR2–/–×TLR4d/d mice also attracted fewer polymorphonuclear neutrophils into the lung, while TLR4d/d mice recruited them. Attenuated recruitment of polymorphonuclear neutrophils correlated with reduced weight loss in TLR2–/– and TLR2–/–×TLR4d/d mice and a lower chlamydial burden 3 days post infection. At 9 days post infection, TLR2–/– and TLR2–/–×TLR4d/d mice produced cyto‐ and chemokines as efficiently as wild‐type mice, indicating that the involvement of TLR in inflammation varies over time. All TLR2–/–×TLR4d/d mice succumbed to the infection, while about 50% of TLR2–/– mice died. Taken together, the function of TLR2 and TLR4 is required to survive pulmonary infection with C. pneumoniae.
An Efficient Synthesis of Achiral and Chiral Cyclic Dehydro‐α‐Amino Acid Derivatives Through Nucleophilic Addition of Amines to β,γ‐Unsaturatedα‐Keto Esters
Authors: Palacios Francisco , Vicario Javier , Aparicio Domitila 
Published: April 2006

AbstractA very simple and efficient synthesis of 3‐amino‐1,5‐dihydro‐2H‐pyrrol‐2‐ones is reported. These cyclic dehydro‐amino acid derivatives with a stereogenic center at the 5‐position were obtained by the addition of two equivalents of amine to β,γ‐unsaturated keto esters. These cyclic enamines can also be obtained by the three‐component reaction of ethyl pyruvate, amines and aldehydes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
The Underestimated Role of Counter Ions in Electrostatic Self‐Assembly:[1+1] Cavitand‐Calix[4]arene Capsules Based on Azinium–Sulfonate Interactions
Authors: Oshovsky Gennady V. , Reinhoudt David N. , Verboom Willem 
Published: April 2006

AbstractThe apparent Ka values of the formation of [1+1] cavitand‐calix[4]arene capsules, based on azinium–sulfonate electrostatic interactions, obtained by direct titration experiments are concentration dependent due to the influence of the interaction of the charged capsule components with their initial counterions. 1H NMR and UV dilution experiments, in which this ion‐pairing is excluded, gave Ka‐values larger than 2·106 M–1 in methanol and methanol/water (1:1) for the capsule formation. The capsule encapsulates small guests like methanol, ethanol, etc., as proven by ESI‐MS. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Disposable Screen‐Printed Edge Band Ultramicroelectrodes for the Determination of Trace Amounts of Nitrite Ion
Authors: Chang Jen‐Lin , Zen Jyh‐Myng 
Published: April 2006

AbstractThe application of linear scan voltammetry for sensitive determination of nitrite by using a disposable screen‐printed edge band carbon ultramicroelectrode (designated as SPUME) was reported in this study. The measurement with the SPUME can be performed in solutions of low ionic strength, e.g., natural waters, because the ohmic loses are negligible. The limiting oxidation current of nitrite showed a wide linear range up to 3 mM at the SPUME. A relative standard deviation of 2.46% (n=5) for analyzing 5 μM nitrite indicated a detection limit (S/N=3) of 0.38 μM. Real sample analysis of mineral and ground water samples as well as bratwurst food product showed satisfactory results. Since the SPUME is low cost and easy for mass production, the disposable nature further offers to application in diverse field of electroanalytical chemistry.
Determination of Trace Tin by Anodic Stripping Voltammetry at a Carbon Paste Electrode
Authors: Li Yi‐Heng , Xie Hong‐Qi , Zhou Fang‐Qin , Guo Hui‐Shi 
Published: April 2006

AbstractA sensitive and selective procedure for the determination of trace tin at a carbon paste electrode was described. Each measurement cycle consisted of three steps: accumulation, reduction and stripping. The tin complex with bromopyrogallol red (BPR) was accumulated on the electrode surface in 0.10 mol/L acetate buffer (pH 4.5). After electrochemical reduction of Sn(II) had been carried out, the reoxidation wave of Sn(0) appeared at −0.69 V (vs. SCE) on scanning the potential in the positive direction in 4.0 mol/L HCl. For a preconcentration time of 2 min, the detection limit was 0.06 μg/L (5×10−10 mol/L ) and the linear range was from 0.1 to 50 μg/L. The proposed method was applied to the determination of tin in canned food and waste water samples with satisfactory results.
Carbon Powder Based Films on Traditional Solid Electrodes as an Alternative to Disposable Electrodes
Authors: Yosypchuk Bogdan , Barek Jiří , Fojta Miroslav 
Published: April 2006

AbstractThe covering of conventional solid electrode with a film using an ink containing a conductive powder and a polymer enables to broaden the potential window of the original solid electrode. A solid silver amalgam electrode covered with such a film exhibits a potential window from −600 mV to +1400 mV vs. SCE reference electrode. The renewal of the film is fast and simple: the electrode can be simply wiped with a filter paper to remove the old film and immersed into an ink solution or 1–2 μL of this ink solution can be applied to the surface of the electrode with a micro dispenser to form a new film. Therefore, just the inexpensive film at the electrode surface is disposable and there is no need to dispose the whole, more expensive electrode. Moreover, when a suitable electrochemical pretreatment of the film electrode is applied, the same film can be used for reproducible measurements for several days.
Electrochemical Detection of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, and IO$\rm{ {_{3}^{-}}}$ at a Phosphomolybdic Acid Linked 3‐Aminopropyl‐Trimethoxysilane Modified Electrode
Authors: Rahman Md. Aminur , Won Mi‐Sook , Wei Pei‐Hai , Shim Yoon‐Bo 
Published: April 2006

AbstractA composite film modified electrode containing a Keggin‐type heteropolyanion, H3(PMo12O40)⋅H2O, was fabricated with 3‐aminopropyltrimethoxysilane (APMS) attached on an electrochemically activated glassy carbon (GC) electrode through the formation of COSi bond. PMo12O$\rm{ {_{40}^{3-}}}$ was then complexed with APMS through the electrostatic interaction between the phosphate groups of PMo12O$\rm{ {_{40}^{3-}}}$ and amine groups of APMS (PMo12O$\rm{ {_{40}^{3-}}}$‐APMS). XPS and cyclic voltammetry were employed for characterization of the composite film. The PMo12O$\rm{ {_{40}^{3-}}}$‐APMS modified electrode showed three reversible redox pairs with smaller peak‐separation and was stable in the larger pH range compared with that in a solution phase. The catalytic properties of the modified electrode for the reduction of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, and IO$\rm{ {_{3}^{-}}}$ were studied and the modified electrode exhibited good electrocatalytic activities for the three anions. The experimental parameters, such as pH, temperature, and the applied potential were optimized. The detection limits were determined to be 7.0±0.35 μM, 4.0±0.17 μM, and 0.1±0.04 μM for ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, and IO$\rm{ {_{3}^{-}}}$ , respectively. The modified electrode was applied to natural water samples for the detection of ClO$\rm{ {_{3}^{-}}}$, BrO$\rm{ {_{3}^{-}}}$, and IO$\rm{ {_{3}^{-}}}$.
Microwave Activation of Processes in Mesopores: The Thiourea Electrooxidation at Mesoporous Platinum
Authors: Ghanem Mohamed A. , Coles Barry A. , Compton Richard G. , Marken Frank 
Published: April 2006

AbstractIn situ microwave activation is applied to the electrochemical oxidation of thiourea at low surface area (polished polycrystalline) and at high surface area (electrodeposited mesoporous platinum coated) platinum microelectrodes. The one electron oxidation of thiourea to formamidine disulfide is monitored as a function of the different activation parameters. In the absence of microwaves (ambient temperature, low mass transport) increasing the surface area (roughness) increases the thiourea oxidation response predominantly due to adsorption effects. In the presence of high microwave intensities, high mass transport and thermal effects further increase the oxidation current at mesoporous platinum. The most effective thickness of the mesoporous platinum film for the thiourea oxidation process is estimated as 3 μm independent of electrode diameter, temperature, or mass transport effects.
Universal interpolating function for the dispersion coefficient of DNA fragments in sieving matrices
Authors: Mercier Jean‐François , Slater Gary W. 
Published: April 2006

AbstractThe separation of DNA fragments by (slab or capillary) gel electrophoresis has been studied extensively. To characterize the separation achieved by such systems, one needs to understand the impact (and their dependency upon the experimental quantities) of two physical parameters: the electrophoretic mobility μ and the diffusion coefficient D. Three different regimes have been shown to exist for both μ and D: the Ogston regime, the reptation regime and the reptation with orientation regime (note that separation is only possible for the first two regimes). In the small electric field limit, both μ and D are apparently well described by theories for all three regimes. Unfortunately this results in disjointed scaling laws and no theory‐based general equations can apply to all regimes. Recently, an empirical interpolating formula has been proposed that adequately fits the low electric field mobility μ of dsDNA fragments across all three regimes and is compatible with accepted theories. In this article we review and clarify the current state of knowledge regarding the size dependence of the mobility and the diffusion coefficient and propose an interpolating formula for molecular size dependence of the low field diffusion coefficient D. With formulas for both the mobility and the diffusion coefficient as a function of the experimental conditions one could, in principle, optimize any gel/polymer matrix‐based electrophoresis system for a wide range of DNA molecular sizes.
Improved 2‐DE of microorganisms after acidic extraction
Authors: Herbert Ben R. , Grinyer Jasmine , McCarthy John T. , Isaacs Mitchell , Harry Elizabeth J. , Nevalainen Helena , Traini Mathew D. , Hunt Sybille , Schulz Ben , Laver Matthew , Goodall Anthony R. , Packer Joanne , Harry Jenny L. , Williams Keith L. 
Published: April 2006

Abstract2‐DE separations of protein extracts sometimes have problems with poor resolution and streaking. This problem is particularly apparent with microorganisms, most notably those with a large cell wall. Here we describe a novel, rapid protocol for the extraction of microorganisms in acidic conditions, leading to increased resolution and 2‐D gel quality. The efficiency of the protocol is demonstrated with extracts of bacteria, Escherichia coli and Bacillus subtilis; fungus, Trichoderma harzianum and yeast, Saccharomyces cerevisiae. We also demonstrate using a membrane centrifugal filtration, that large acidic molecules in excess of 100 kDa, probably including cell wall material, are responsible for the separation difficulties. A range of acidic extraction conditions were investigated, and it was found that optimal extraction is achieved using an extraction solution acidified to pH 3 by 80 mM citric acid. These findings have significant implications for the proteomic study of many medically, agriculturally and environmentally significant microorganisms, as the cell walls of these organisms are often considerably more complex than many commonly studied laboratory strains.
The human heart proteome: Two‐dimensional maps using narrow‐range immobilised pH gradients
Authors: Westbrook Jules A. , Wheeler Jun X. , Wait Robin , Welson Sandy Y. , Dunn Michael J. 
Published: April 2006

AbstractThe analysis of complex proteomes is undertaken using a variety of techniques and technologies such as 2‐DE, surface‐enhanced laser desorption ionisation, and various types of MS. In order to overcome the complexities of protein expression in discrete proteomes, sample fractionation has become an important aspect of proteomic experiments. The use of narrow‐range IPGs (nrIPGs) is of special importance using the 2‐DE proteomics workflow, since an enhanced visualisation of a given proteome is achieved through an improved physical separation and resolution of proteins. The work described in this paper presents a series of protein maps of the human heart left ventricle proteome that have been generated using nrIPGs for the first, IEF, dimension of 2‐DE. A total of 374 gel spots were excised from seven different pH gradients, covering the range pH 3–10, giving rise to a total of 388 identifications from 110 unique proteins. Using Gene Ontologies (GOs), the identified proteins were found to be associated with 97 types of GO Process, 144 types of GO Function, and 54 types of GO Component. It is hoped that the maps presented in this paper will be of use to other researchers for reference purposes.
Role of chemical structure in stereoselective recognition of beta‐blockers and H1‐antihistamines by human serum transferrin in capillary zone electrophoresis
Authors: Gagyi László , Gyéresi Árpád , Kilár Ferenc 
Published: April 2006

AbstractStudies on chiral resolution of beta‐blocker and H1‐antihistamine drugs by CZE using human serum transferrin are described. The drugs with different structures passed a pseudostationary protein zone in a coated capillary applying the partial filling method for the chiral separation. In this study we screened 15 compounds; most of them showed longer migration time, indicating an interaction with transferrin. Stereoselective interaction was observed only for five beta‐blockers (celiprolol, talinolol, mepindolol, bopindolol, and oxprenolol) and for one H1‐antihistamine (brompheniramine). The most important finding was that very small differences in the chemical structure of the drug resulted in significant changes in the stereoselective recognition. Resolution of mepindolol enantiomers was observed showing the essential role of one methyl group compared to pindolol, which is not resolved by transferrin. Bopindolol, also a derivative of pindolol having bigger difference in the structure, showed more experienced separation. The very slight difference between alprenolol and oxprenolol was also revealed with these methods, since only oxprenolol enantiomers, having an extra oxygen in the structure, are resolved. Determining the migration order of the eutomers and distomers (chlorpheniramine, brompheniramine) we can deduct conclusions about the role of serum proteins in the delivery of drugs within the body.
Estimating the long memory granger causality effect with a spectrum estimator
Authors: Chen Wen‐Den 
Published: April 2006

AbstractThis paper discusses the Granger causality test by a spectrum estimator which allows the transfer function to have long memory properties. In traditional methodology the relationship among variables is usually assumed to be short memory or contemporaneous. Hence, we have to make sure they are of the same integrated order, else there might be a spurious regression problem. In practice, not all the variables are fractionally co‐integrated in the economic model. They may have the same random resources, but under a different integrated order. This paper focuses on how to capture the long memory Granger causality effect in the transfer function. This does not necessarily assume the variables are of the same fractional integrated order. Moreover, by the transfer function we construct an estimator to test the long memory effect with the Granger causality sense. Copyright © 2006 John Wiley & Sons, Ltd.
[1‐Me‐1‐closo‐SnB11H11]− as a potential weakly coordinating anion: Synthesis of Rh(PPh3)2(1‐Me‐closo‐SnB11H11) and comparisons with Rh(PR3)2 (1‐H‐closo‐CB11 H11)
Authors: Molinos Eduardo , Player Thomas P. H. , Kociok‐Köhn Gabriele , Ruggerio Giuseppe D. , Weller Andrew S. 
Published: April 2006

AbstractThe closo‐stannaborane salt [Rh(PPh3)2‐(nbd)][1‐Me‐1‐closo‐SnB11H11] reacts with H2 in CH2 Cl2 solution to afford the contact ion‐pair Rh(PPh3)2(1‐Me‐closo‐SnB11H11), which has been characterized in solution and the solid state by X‐ray diffraction. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:174–180, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20218
Metallacyclopentadienes and related heterocycles via 1,1‐organoboration of alkyn‐1‐ylmetal compounds
Authors: Wrackmeyer Bernd 
Published: April 2006

AbstractMetallacyclopentadienes (metalloles) containing M = Si, Ge, Sn, Pb, Ti, Pt can be prepared by 1,1‐organoboration of alkyn‐1‐ylmetal compounds LnMCCR1(R1 = H, alkyl, aryl, silyl, etc; L depends on M, and can be hydrogen, alkyl, aryl, Cl, Br, amino groups, a chelating diphosphane, and one or more L can be again alkynyl groups). These reactions proceed via activation of the MC bond(s) by an electron‐deficient triorganoborane BR3 (R = alkyl, aryl; non‐cyclic, monocyclic, bicyclic, and tricyclic boranes), at first intermolecular and then intramolecular. In the course of these reactions, the MC bonds are cleaved, zwitterionic alkynylborate‐like intermediates are formed, in which the metal‐containing fragments are coordinated side‐on to the CC bonds. In most cases, the 1,1‐organoboration reactions tolerate various functional groups at the alkyne as well as at the metal. The characterization of intermediates and final products by X‐ray structural analysis and by multinuclear magnetic resonance spectroscopy (NMR) is documented and described. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:188–208, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20222
Synthesis and structure of the coordinatively unsaturated boron subphthalocyanine cation, [B(SubPc)]+
Authors: Kato Tsuyoshi , Tham Fook S. , Boyd Peter D. W. , Reed Christopher A. 
Published: April 2006

AbstractThe boron subphthalocyanine cation, B(SubPc)+, has been prepared as a salt of a weakly coordinating carborane anion, CHB11Me5Br6−, by a metathesis reaction of Et3Si(CHB11Me5Br6) with B(SubPc)Cl. The separation of the cation and anion in the X‐ray structure indicates coordinative unsaturation at the boron center, and this is corroborated by DFT calculations. A strongly Lewis acidic nature for the B(SubPc)+ cation is indicated by its hydrolysis to an unusual product, the di‐meso‐N‐protonated μ‐oxo dimer, [H(SubPc)B‐O‐B(SubPc)H]2+. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:209–216, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20223
Reactivity of terminal transition metal borylene complexes
Authors: Braunschweig Holger , Rais Daniela 
Published: April 2006

AbstractThe chemistry of terminal transition metal borylene complexes is reviewed, with particular attention to recent developments concerning the reactivity of these species. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:238–238, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20247
Theoretical analysis on thermoelectric power generation with rectangular‐fin elements and its applicability in micro systems
Authors: Oda Yutaka , Yoshida Hideo 
Published: April 2006

AbstractA thermoelectric module, which consists of rectangular‐fin elements and has a simple structure suitable for micro fabrication, was newly proposed for a micro‐ to milli‐scale thermoelectric power generator. A unit model was introduced to examine the basic characteristics of thermoelectric power generation with rectangular‐fin elements. Theoretical descriptions of the power density and conversion efficiency were given by solving one‐dimensional heat and current flows inside the elements. Then, it was found that there exist optimum aspect ratios of the elements to achieve maximum power density and conversion efficiency. Power density becomes larger if the module is downsized with a similarity in shape, while conversion efficiency remains constant, i.e., smaller devices show better performance. Finally, comparative analysis with a standard pi‐type module was conducted to emphasize the superiority of the proposed module in micro systems, when convective heat transfer resistance is taken into account. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 224–244, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20108
The heat transfer and pressure drop characteristics of finned tube banks in forced convection (effects of fin height on pressure drop characteristics)
Authors: Kawaguchi Kiyoshi , Okui Kenichi , Asai Toshihiro , Hasegawa Yutaka 
Published: April 2006

AbstractIn recent years the requirement for the reduction of energy consumption has been increasing to solve the problems of global warming and the shortage of petroleum resources. For example, in the power generation field, as thermal power generation occupied 60% of the power generation demand, considerable improvement of the thermal efficiency is required. This paper describes the pressure drop characteristics of finned tube banks used for heat exchangers in thermal power generation that were clarified by testing serrated finned tube banks with different fin heights for improved heat transfer and conventional spiral finned tube banks with different fin heights, and an equation to predict pressure drop which is necessary for the heat exchanger design is proposed. © 2006 Wiley Periodicals, Inc. Heat Trans Asian Res, 35(3): 179–193, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20112
Cannabinoid agonist WIN55,212‐2 induces apoptosis in cerebellar granule cells via activation of the CB1 receptor and downregulation of bcl‐xL gene expression
Authors: Pozzoli Giacomo , Tringali Giuseppe , Vairano Mauro , D'Amico Monia , Navarra Pierluigi , Martire Maria 
Published: April 2006

AbstractThe endogenous cannabinoid system is involved in the regulation of a number of physiologic effects in both the central and peripheral nervous systems. Its role in the control of neuronal cell proliferation has attracted major attention because of its potential implications for new therapeutic strategies. In the present study, we demonstrated that treatment of cultured cerebellar granule cells with the synthetic cannabinoid WIN55,212‐2, causes cell‐body and nuclear shrinkage, which are hallmarks of neuronal apoptosis, as well as concentration‐dependent decrease in cell viability. Staining with the fluorescent nuclear dye, Hoechst 33258, revealed apoptosis in 27.1% and 58.5% of cells exposed to 1 and 10 μM of WIN55,212‐2, respectively (P < 0.01 and P < 0.001 vs. control respectively) after 36 hr. After 24 hr of exposure to WIN55,212‐2, mRNA levels for the anti‐apoptotic gene bcl‐xL were reduced to 45.6% of those found in control (P < 0.01). These effects were completely reverted when cells were exposed to the synthetic cannabinoid in the presence of the specific CB1‐receptor antagonist, SR141716A (1 μM). Moreover, the pro‐apoptotic effect of 10 μM WIN55,212‐2 could be reduced by the addition to the incubation medium of a cell‐permeant inhibitor of caspase‐1 (50 nM). Finally, WIN55,212‐2 significantly increased caspase‐1 activity after 24 hr. These findings show that the activation of CB1 receptors on cerebellar granule cells induces apoptotic cell death, which is associated with downregulation of the anti‐apoptotic gene, bcl‐xL, and at least in part, activation of caspase‐1. © 2006 Wiley‐Liss, Inc.