bluuebunny/crossref_metadata_2025_split huggingface dataset:
Bright lights, clearly visible in the healthcare R&D tunnel, could burn out for lack of funds
Authors: Moos Walter H. , Rurka James E. , Miller Susan M. 
Published: November 2009

AbstractBright lights have never been more visible in healthcare R&D, each heralding innovative approaches to disease diagnosis, treatment, or prevention. Unfortunately, this promise of continued healthcare innovation is increasingly threatened by inadequate funding of R&D at many levels: in academic and nonprofit organizations, in small business ventures, and even in large pharmaceutical companies. If we are to continue transforming the practice of medicine, we must ensure that R&D funding levels are made sufficient to leverage recent scientific advances into important new medicines. Thanks to legions of dedicated researchers over the last century, we are making significant progress against major killers. The next generation of drugs and biologics could delay the onset of neurodegenerative diseases like Alzheimer's for long enough to be considered a “cure.” Current experience with pandemic swine flu has acquainted the population‐at‐large with an idea of the magnitude of potential risks created by a “bad bugs, no drugs” scenario. Innovative biomedical R&D has been so successful for so long that many of us who live in the developed world now consider good health to be an entitlement. We simply cannot afford to miss the enormous opportunities now coming into focus, which promise to relieve suffering, reduce morbidity, and eliminate so many needless deaths. Several focal points are recommended as the basis around which we might begin to address these needs at the NIH and FDA, along with small businesses and big pharma. Drug Dev Res 70:457–460, 2009. © 2009 Wiley‐Liss, Inc.
A Novel Hydrogen Peroxide Amperometric Sensor based on Thionin Incorporated onto a Mo6S9‐xIx Nanowire Modified Glassy Carbon Electrode
Authors: Lin Hong , Cheng Huiming , Miao Xiaopei , Papakonstantinou Pagona , Mihailovič Dragan , Li Meixian 
Published: November 2009

AbstractA simple and enzymeless amperometric sensor for the detection of H2O2 based on a new kind of nanomaterial Mo6S9−xIx (MoSI) nanowires (NWs) was developed. The construction of the sensing platform was based on strong electrostatic interactions between negatively charged MoSI NWs and positively charged thionin molecules. MoSI NWs act as not only a good substrate for the immobilization of redox mediator thionin, but also a promoter for electrocatalysis of H2O2. The fabricated sensor showed a wide linear range over the concentration of H2O2 from 5 μM to 2.8 mM with a measurable lowest detection of 0.8 μM; furthermore, it exhibited good stability and reproducibility.
Simultaneous Determination of Cadmium, Lead, Copper and Mercury Ions Using Organofunctionalized SBA‐15 Nanostructured Silica Modified Graphite–Polyurethane Composite Electrode
Authors: Cesarino Ivana , Cavalheiro Éder T. G. , Brett Christopher M. A. 
Published: November 2009

AbstractA new sensor has been developed for the simultaneous detection of cadmium, lead, copper and mercury, using differential pulse and square wave anodic stripping voltammetry (DPASV and SWASV) at a graphite–polyurethane composite electrode with SBA‐15 silica organofunctionalized with 2‐benzothiazolethiol as bulk modifier. The heavy metal ions were preconcentrated on the surface of the modified electrode at −1.1 V vs. SCE where they complex with 2‐benzothiazolethiol and are reduced to the metals, and are then reoxidized. Optimum SWASV conditions lead to nanomolar detection limits and simultaneous determination of Cd2+, Pb2+, Cu2+ and Hg2+ in natural waters was achieved.
Simultaneous Voltammetric Detection of Salsolinol and Uric Acid in the Presence of High Concentration of Ascorbic Acid with Gold Nanoparticles/Functionalized Multiwalled Carbon Nanotubes Composite Film Modified Electrode
Authors: Zhang Shaojun , Xu Minglu , Zhang Yuzhong 
Published: November 2009

AbstractThis work demonstrates gold nanoparticles (AuNPs)/functionalized multiwalled carbon nanotubes (f‐MWCNT) composite film modified gold electrode via covalent‐bonding interaction self‐assembly technique for simultaneous determination of salsolinol (Sal) and uric Acid (UA) in the presence of high concentration of ascorbic acid (AA). In pH 7.0 PBS, the composite film modified electrode exhibits excellent voltammetric response for Sal and UA, while AA shows no voltammetric response. The oxidation peak current is linearly increased with concentrations of Sal from 0.24–11.76 μmol L−1 and of UA from 3.36–96.36 μmol L−1, respectively. The detection limits of Sal and UA is 3.2×10−8 mol L−1 and 1.7×10−7 mol L−1 , respectively.
Iron(III)‐Complexes Engaged in the Biochemical Processes in Seawater. I. Voltammetry of Fe(III)‐Succinate Complexes in Model Aqueous Solution
Authors: Cmuk Petra , Piantanida Ivo , Mlakar Marina 
Published: November 2009

AbstractFe3+ complexes with succinic acid, a ligand naturally present in seawater, were investigated in aqueous solutions by square‐wave and cyclic voltammetry. [Fe(suc)2(OH)2] and [Fe(suc)3] were detected at potentials −0.22 and −0.37 V, depending on Csuc in the ranges from 0.01 to 0.07 and 0.1 to 0.5 mol L−1, respectively. Redox processes were irreversible, first with reactant adsorption and second diffusion controlled, both accompanied by chemical step. By UV/Vis spectra formation of these complexes was confirmed and equilibrium constant Fe(suc)2(OH)2⇌Fe(suc)3 calculated (logK2−3=(1.14±0.15) mol−1 L), as well as their perceptible stoichiometry. With NTA as competing ligand, conditional stability constant of [Fe(suc)2(OH)2] complex was calculated (βcond=(3.1±1.3)×1022 mol−1 L).
Bismuth/Polyaniline/Glassy Carbon Electrodes Prepared with Different Protocols for Stripping Voltammetric Determination of Trace Cd and Pb in Solutions Having Surfactants
Authors: Wang Z. M. , Guo H. W. , Liu E. , Yang G. C. , Khun N. W. 
Published: November 2009

AbstractTo improve reproducibility, stability and sensitivity, a bismuth (Bi) thin film was coated on glassy carbon (GC) substrates which surfaces were modified with a porous thin layer of polyaniline (PANI) via multipulse potentiostatic electropolymerization to form Bi/PANI/GC electrodes (Bi/PANI/GCEs). The Bi/PANI/GCEs were used successfully for simultaneous detection and determination of Cd2+ and Pb2+ ions, and various parameters were studied with reference to square wave anodic stripping voltammetric (SWASV) signals. The experimental results depicted that the environment‐friendly Bi/PANI/GCEs had the ability to rapidly monitor trace heavy metals even in the presence of surface‐active compounds.
Electrochemical Dissolution of Silver Nanoparticles and Its Application in Metalloimmunoassay
Authors: Szymanski Mateusz , Turner Anthony P. F. , Porter Robert 
Published: November 2009

AbstractThis work demonstrates the use of silver nanoparticles as a simple electrochemical biolabel to induce 106 signal enhancement. We propose a mechanism of measuring the silver nanoparticles on a specific screen‐printed planar carbon electrode, without the requirement for the harsh oxidant or toxic reagents described in prior‐art for gold sol methods. The possible measurement process was validated with orthogonal techniques such as UV/Vis spectroscopy, dynamic light scattering and by anodic stripping voltammetry (ASV). The findings were utilized to develop a novel electrochemical sandwich immunoassay where the analyte concentration is directly proportional to ASV oxidation peak of silver. This technique in the future is envisaged to form the foundation of a generic Point of Care platform. The assay was applied to cardiac marker: myoglobin with detection limit of 3 ng/mL.
Highly Selective and Sensitive Detection of Dopamine in the Presence of Excessive Ascorbic Acid Using Electrodes Modified with C60‐Functionalized Multiwalled Carbon Nanotube Films
Authors: Zhu Huarui , Wu Wei , Zhang Hua , Fan Louzhen , Yang Shihe 
Published: November 2009

AbstractElectrochemical detection of dopamine (DA) in the presence of a large excess of ascorbic acid (AA) was investigated with a novel all‐carbon nanocomposite film of C60‐MWCNTs (C60‐functionalized multi‐walled carbon nanotubes) using a bare MWCNTs film as control. Although both films can selectively detect DA from AA by separating their oxidation potentials, the C60‐MWCNTs film shows special selectivity and good sensitivity for detecting DA. On one hand, the C60‐MWCNTs composite film shows a higher activity for DA oxidation with enhanced peak current. On the other hand, the C60‐MWCNTs composite film effectively suppresses the oxidation of AA. Remarkably, it is found that the oxidation current of DA is over 2 times higher than that of AA even when the concentration of AA is about 3 to 4 orders of magnitude higher than that of DA. This offers a tremendous advantage for the simple and clean detection of DA free of the interfering AA signal in a real assay. Cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectrometry are used to characterize the C60‐MWCNTs composite film. These novel properties are interpreted to arise from the facile electron transfer between C60 and MWCNTs in the C60‐MWCNTs nanocomposite film.
Electrical and Sensing Properties of Single‐Walled Carbon Nanotubes Network: Effect of Alignment and Selective Breakdown
Authors: Lim Jae‐Hong , Phiboolsirichit Nopparat , Mubeen Syed , Rheem Youngwoo , Deshusses Marc A. , Mulchandani Ashok , Myung Nosang V 
Published: November 2009

AbstractThe electrical transport and NH3 sensing properties of randomly oriented and aligned SWNT networks were presented and discussed. The results indicate that aligned SWNT‐FETs have better FET characteristics due to the reduced number of interconnected nodes. This was particularly true as the resistance of the devices increased. Gated electrical breakdown was implemented to selectively remove metallic (m‐) SWNTs, thereby reducing scattering centers. This technique provided significant improvements in FET characteristics resulting in greater on/off ratio (e.g. 104). AC dielectrophoretic alignment followed by selective electrical breakdown of m‐SWNTs can significantly enhance the semiconducting properties of SWNT networks which resulted in highly sensitive sensors.
Nrf2 regulates microglial dynamics and neuroinflammation in experimental Parkinson's disease
Authors: Rojo Ana I. , Innamorato Nadia G. , Martín‐Moreno Ana M. , De Ceballos María L. , Yamamoto Masayuki , Cuadrado Antonio 
Published: November 2009

AbstractNeural injury leads to inflammation and activation of microglia that in turn may participate in progression of neurodegeneration. The mechanisms involved in changing microglial activity from beneficial to chronic detrimental neuroinflammation are not known but reactive oxygen species (ROS) may be involved. We have addressed this question in Nrf2‐knockout mice, with hypersensitivity to oxidative stress, submitted to daily inoculation of 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP) for 4 weeks. Basal ganglia of these mice exhibited a more severe dopaminergic dysfunction than wild type littermates in response to MPTP. The amount of CD11b‐positive/CD45‐highly‐stained cells, indicative of peripheral macrophage infiltration, did not increase significantly in response to MPTP. However, Nrf2‐deficient mice exhibited more astrogliosis and microgliosis as determined by an increase in messenger RNA and protein levels for GFAP and F4/80, respectively. Inflammation markers characteristic of classical microglial activation, COX‐2, iNOS, IL‐6, and TNF‐α were also increased and, at the same time, anti‐inflammatory markers attributable to alternative microglial activation, such as FIZZ‐1, YM‐1, Arginase‐1, and IL‐4 were decreased. These results were confirmed in microglial cultures stimulated with apoptotic conditioned medium from MPP+‐treated dopaminergic cells, further demonstrating a role of Nrf2 in tuning balance between classical and alternative microglial activation. This study demonstrates a crucial role of Nrf2 in modulation of microglial dynamics and identifies Nrf2 as molecular target to control microglial function in Parkinson's disease (PD) progression. © 2009 Wiley‐Liss, Inc.
An empirical investigation into the causes of failure of the monetary model of the exchange rate
Authors: Smith P. N. , Wickens M. R. 
Published: November 2009

AbstractThe purpose of this paper is to attempt to provide measures of the relative importance of the principal causes of the failure of the monetary model of the exchange rate. Secondly, the random walk hypothesis for the exchange rate is tested. The methodology employed is new and has wide application elsewhere. It involves explicitly modelling the misspecification by time series techniques. The results confirm the importance of the breakdown of the PPP assumption but they also show that misspecification of the money market is equally important. The results further show that lagged information can also improve upon the random walk model of the exchange rate.
The behaviour of U.K. export prices of manufactured goods 1970–1983
Authors: Cuthbertson Keith 
Published: November 2009

AbstractThis paper examines the importance of expectations in the determination of U.K. export prices. Export prices are found to depend upon expectations of total domestic unit costs and foreign prices. The non‐linear restrictions implied by the forward‐looking model are found to hold and it performs adequately relative to a backward‐looking error feedback model. The law of one price is rejected and the evidence is consistent with imperfect competition in export markets.
Zero expenditures and the estimation of engel curves
Authors: Keen Michael 
Published: November 2009

AbstractOver the brief interview periods typical of budget surveys (such as the U.K. Family Expenditure Survey) households' recorded expenditures are liable to be misleading indicators of their underlying consumption. Most starkly, a household may not be observed to purchase commodities that it nevertheless consumes. This paper considers the implications of such measurement errors for the estimation of demand systems, and derives a consistent estimator for the special case of linear Engel curves.
MMP levels in the response to degradable implants in the presence of a hydroxamate‐based matrix metalloproteinase sequestering biomaterial in vivo
Authors: Khan Omar F. , Jean‐Francois Jacques , Sefton Michael V. 
Published: November 2009

AbstractThe inflammatory response to an implanted tissue engineered construct alters the remodeling that occurs and this can diminish the intended therapeutic effect. It was hypothesized that the use of a hydroxamate‐based matrix metalloproteinase (MMP) sequestering biomaterial (MI) in the form of ∼200 μm microspheres would lower the amount and activity of MMP in vivo in response to a subcutaneous, degradable implant (gelatin or Integra® disc). MMP degrade extracellular matrix, facilitating inflammatory cell migration and local remodeling of the implant environment. Gelatin or Integra® discs were implanted subcutaneously in the backs of CD1 mice together with 30 mg of MI microspheres or with 30 mg of similarly sized control poly(methyl methacrylate) (PMMA) microspheres in a paired study. To sample the implant space, weakly adsorbed protein or attached cells were recovered from explanted discs by soaking the discs in PBS overnight at 4°C. Unexpectedly, MMP‐2, ‐8, ‐9, and TIMP‐1 levels were surprisingly similar in this recovered fluid for the two treatments. Also, there were significantly more (and at day 4 an order of magnitude more) leukocytes recovered from the gelatin discs coimplanted with the MI microspheres than with the PMMA control. It is suggested that the MI microspheres disturbed the natural MMP control pathway leading to high‐leukocyte numbers, especially at early times. These results highlight the challenge associated with controlling the fate of tissue engineered constructs in vivo. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Preparation and in vitro evaluation of bioactive glass (13–93) scaffolds with oriented microstructures for repair and regeneration of load‐bearing bones
Authors: Fu Qiang , Rahaman Mohamed N. , Bal B. Sonny , Brown Roger F. 
Published: November 2009

AbstractBioactive glass (13–93) scaffolds with oriented microstructures, referred to as ‘columnar’ and ‘lamellar’, were prepared by unidirectional freezing of suspensions, and evaluated in vitro for potential use in the repair and regeneration of load‐bearing bones in vivo. Both groups of scaffolds showed an ‘elastic–plastic’ mechanical response in compression, large strain for failure (>20%), and strain rate sensitivity, but the columnar scaffolds had the additional advantages of higher strength and larger pore width. At the equivalent porosity (55–60%) and deformation rate (0.5 mm/min), the columnar scaffolds had a compressive strength of 25 ± 3 MPa, elastic modulus of 1.2 GPa, and pore width of 90–110 μm, compared to values of 10 ± 2 MPa, 0.4 GPa, and 20–30 μm, respectively, for the lamellar scaffolds. Cellular response to the scaffolds was evaluated using murine MLO‐A5 cells, an osteogenic cell line. While the cellular response to both groups of scaffolds was better than control wells, the columnar scaffolds with the larger pore width provided the most favorable substrate for cell proliferation and function. These results indicate that 13–93 bioactive glass scaffolds with the columnar microstructure could be used for the repair and regeneration of load‐bearing bones in vivo. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Biocompatibility of polyhydroxyalkanoate as a potential material for ligament and tendon scaffold material
Authors: Rathbone S. , Furrer P. , Lübben J. , Zinn M. , Cartmell S. 
Published: November 2009

AbstractThere is a strong need for new biodegradable materials that are suitable for scaffolds in tissue engineering of tendons and ligaments. In many cases, quick degradation rates are favorable, however, with respect to ligament and tendon replacement, slowly degrading polymers are clearly favored. Prime candidates are members of the large class of polyhydroxyalkanoates (PHAs), which are thermoplastic/elastomeric biopolyesters that are slowly degraded by surface erosion. Moreover, their physico‐mechanical properties can be tailored during biosynthesis in bacteria or by chemical modifications. They may be spun into fibers, coated on surfaces or be part of composites. This study has investigated the biocompatability of seven different thermoplastic or elastomeric PHAs using L929 murine fibroblast cells. Cell viability and proliferation over 7 days was analyzed with live/dead staining and a picogreen assay. In addition, extracellular matrix production was measured with the hydroxyproline assay after 14 days. It was found that cell attachment to the PHA film ranged from 85–99% after 7 days. Three PHA films (PHBV (92/8), PHOUE‐POSS and PHUE‐O3) supported similar cell viability in comparison to the controls performed on tissue culture plastic (polystyrene), whereas the biomaterials (PHUA, PHUE, PHB and PHOUE) showed fewer viable cells than in controls. PHB, PHUE‐O3, and PHBV with a water contact angle below 85° supported a similar amount of collagen production in comparison to the tissue culture plastic controls. PHUA, PHUE, PHOUE, and PHOUE‐POSS showed a decrease in collagen production in comparison to the controls after 14 days. Overall, PHB, PHBV, and PHUE‐O3 demonstrated good performance with regards to potential use as a tissue‐engineering scaffold. © 2009 Wiley Periodicals, Inc. J Biomed Mater Res, 2010
Inhibition of tumor proteasome activity by gold–dithiocarbamato complexes via both redox‐dependent and ‐independent processes
Authors: Zhang Xia , Frezza Michael , Milacic Vesna , Ronconi Luca , Fan Yuhua , Bi Caifeng , Fregona Dolores , Dou Q. Ping 
Published: November 2009

AbstractWe have previously reported on a gold(III) complex, namely [AuBr2(DMDT)] (N,N‐dimethyldithiocarbamate) showing potent in vitro and in vivo growth inhibitory activities toward human cancer cells and identifying the cellular proteasome as one of the major targets. However, the importance of the oxidation state of the gold center and the involved mechanism of action has yet to be established. Here we show that both gold(III)− and gold(I)–dithiocarbamato species, namely [AuBr2(ESDT)] (AUL12) and [Au(ESDT)]2 (AUL15), could inhibit the chymotrypsin‐like activity of purified 20S proteasome and 26S proteasome in human breast cancer MDA‐MB‐231 cells, resulting in accumulation of ubiquitinated proteins and proteasome target proteins, and induction of cell death, but at significantly different levels. Gold(I)‐ and gold(III)‐compound‐mediated proteasome inhibition and cell death induction were completely reversed by the addition of a reducing agent, dithiothreitol or N‐acetyl‐L‐cysteine, suggesting the involvement of redox processes. Furthermore, treatment of MDA‐MB‐231 cells with gold(III) compound (AUL12), but not the gold(I) analog (AUL15), resulted in the production of significant levels of reactive oxygen species. Our study provides strong evidence that the cellular proteasome is an important target of both gold(I) and gold(III)–dithiocarbamates, but distinct cellular mechanisms of action are responsible for their different overall effect. J. Cell. Biochem. 109: 162–172, 2010. © 2009 Wiley‐Liss, Inc.
Protein alterations induced by long‐term agonist treatment of HEK293 cells expressing thyrotropin‐releasing hormone receptor and G11α protein
Authors: Drastichova Zdenka , Bourova Lenka , Hejnova Lucie , Jedelsky Petr , Svoboda Petr , Novotny Jiri 
Published: November 2009

AbstractThis study aimed to determine whether sustained stimulation with thyrotropin‐releasing hormone (TRH), a peptide with important physiological functions, can possibly affect expression of plasma membrane proteins in HEK293 cells expressing high levels of TRH receptor and G11α protein. Our previous experiments using silver‐stained two‐dimensional polyacrylamide gel electrophoretograms did not reveal any significant changes in an overall composition of membrane microdomain proteins after long‐term treatment with TRH of these cells (Matousek et al.2005Cell Biochem Biophys 42: 21–40). Here we used a purified plasma membrane fraction prepared by Percoll gradient centrifugation and proteins resolved by 2D electrophoresis were stained with SYPRO Ruby gel stain. The high enrichment in plasma membrane proteins of this preparation was confirmed by a multifold increase in the number of TRH receptors and agonist stimulated G‐protein activity, compared to postnuclear supernatant. By a combination of these approaches we were able to determine a number of clearly discernible protein changes in the plasma membrane‐enriched fraction isolated from cells treated with TRH (1 × 10−5 M, 16 h): 4 proteins disappeared, the level of 18 proteins decreased and the level of 39 proteins increased. Our concomitant immunochemical determinations also indicated a clear down‐regulation of Gq/11α proteins in preparations from hormone‐treated cells. In parallel, we observed decrease in caspase 3 and alterations in some other apoptotic marker proteins, which were in line with the presumed antiapoptotic effect of TRH. J. Cell. Biochem. 109: 255–264, 2010. © 2009 Wiley‐Liss, Inc.
A novel and green method for the synthesis of highly substituted isoquinoline derivatives in ionic liquid
Authors: Wang Xiang‐Shan , Wu Jian‐Rong , Li Qing , Zhang Mei‐Mei 
Published: November 2009

Abstract
magnified image A series of new highly substituted isoquinoline derivatives was obtained from the reaction of 2‐(1‐substituted piperidin‐4‐ylidene)malononitrile, benzaldehyde and malononitrile or cyanoacetate in ionic liquid at 50°C. This novel procedure was different from the previous method in the synthesis of isoquinoline using pyridine fragment as reactant to construct benzene ring, and as well as had the advantages of one‐pot, mild and environmentally benign. A possible mechanism was proposed based on the further experimental results. J. Heterocyclic Chem., (2009).