bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transjugular approach for transcatheter closure of mitral paraprosthetic leak
Authors: Joseph George , Thomson Viji Samuel 
Published: June 2009

AbstractTranscatheter closure of mitral paraprosthetic leak (PPL) using femoral antegrade transseptal or retrograde approach is often unsuccessful when the involved part of the mitral annulus is difficult to access or when the left atrium is large. We report the successful use of jugular venous approach to perform transseptal antegrade PPL closure in a 49‐year‐old male with mitral PPL located in the anteromedial part of the annulus. This technique could serve as a useful alternative in patients in whom transcatheter closure of mitral PPL is technically difficult. © 2009 Wiley‐Liss, Inc.
Endovascular abdominal aortic stenosis treatment with the optimed self‐expandable nitinol stent
Authors: Ghazi Payam , Haji‐Zeinali Ali‐Mohammad , Shafiee Nahid , Qureshi Shakeel A. 
Published: June 2009

AbstractPurpose: To evaluate the safety and feasibility of self‐expandable stents (OptiMed) for treatment of abdominal aortic stenosis in the situations in which the aortic stenosis locates near the origin of celiac, superior mesenteric, renal and inferior mesenteric arteries. Methods: Five consecutive patients scheduled for endovascular treatment of abdominal aortic stenosis by self‐expandable nitinol stent (Sinus‐Aorta/OptiMed) implantation. The diameter of the stent was chosen as 10–30% more than that of the normal portion of the aorta above the stenosis. Long stents of 60 mm or longer were chosen. After stent deployment, balloon postdilation was performed with a balloon in patients with residual gradient > 5 mm Hg. Results: All patients were successfully treated with the OptiMed stents. The balloon predilation was performed in one patient due to severe stenosis. The mean diameter and length of the stents deployed were 20.4 ± 2.9 (range, 16–24 mm) and 64 ± 8.9 (range, 60–80 mm), respectively. The balloon postdilation was performed in all cases. The mean diameter of the balloons was 13.6 ± 1.5 (range, 12–15 mm). The mean diameter of stenosis increased from 4.8 ± 1.9 to 14.4 ± 1.8 mm after stent placement. The mean peak systolic gradient decreased from 46.8 ± 31.5 mm Hg to 0.8 ± 1.8 mm Hg. During follow‐up (22.8 ± 14.3 months), none of the patients had restenosis within the stent, occlusion of any branches of the aorta, or other related complications. Conclusions: In our small series, we observed that abdominal aortic stenosis can be successfully and effectively treated with OptiMed stents in the situations in which the stenotic segment is located next to the origins of the main visceral branches of abdominal aorta. © 2009 Wiley‐Liss, Inc.
Efficient and Practical Arene Hydrogenation by Heterogeneous Catalysts under Mild Conditions
Authors: Maegawa Tomohiro , Akashi Akira , Yaguchi Kiichiro , Iwasaki Yohei , Shigetsura Masahiro , Monguchi Yasunari , Sajiki Hironao 
Published: June 2009

AbstractAn efficient and practical arene hydrogenation procedure based on the use of heterogeneous platinum group catalysts has been developed. Rh/C is the most effective catalyst for the hydrogenation of the aromatic ring, which can be conducted in iPrOH under neutral conditions and at ordinary to medium H2 pressures (<10 atm). A variety of arenes such as alkylbenzenes, benzoic acids, pyridines, furans, are hydrogenated to the corresponding cyclohexyl and heterocyclic compounds in good to excellent yields. The use of Ru/C, less expensive than Rh/C, affords an effective and practical method for the hydrogenation of arenes including phenols. Both catalysts can be reused several times after simple filtration without any significant loss of catalytic activity.
Electric Field Assisted Effects on Molecular Orientation and Surface Morphology of Thin Titanyl(IV)phthalocyanine Films
Authors: Schuster Britt‐Elfriede , Basova Tamara V. , Peisert Heiko , Chassé Thomas 
Published: June 2009

AbstractHerein we present electric field assisted effects on the molecular orientation, the polymorphism, and the surface morphology of thin titanyl(IV)phthalocyanine (TiOPc) films. The ability of electric fields to affect the thin film structure of polar molecules is demonstrated using titanyl(IV)phthalocyanine as a model compound exhibiting both a permanent and an induced electric dipole moment. Thin films of TiOPc prepared by organic molecular beam deposition (OMBD) in the absence and in the presence of an electric field during the thin film growth are characterized using polarization dependent Raman spectroscopy and atomic force microscopy (AFM). The distinctive pattern of vibrational modes of the phthalocyanine skeleton indicates different molecular orientations in these thin films: Raman spectra of regions where an electric field is present during thin film growth reveal a preferential molecular orientation with an inclination angle of the molecular plane (pseudoplanar macrocycle) with respect to the substrate plane of nearly 90°. Contrary to that, in regions where the electric field was absent, the molecules adopt predominantly a configuration with a smaller tilt angle (∼ 60°). In addition, an electric field assisted change is apparent in AFM images: A large amount of well‐formed steplike crystallites lying parallel to the substrate is observed when no electric field was present, whereas in the case when an electric field was applied during thin film growth the crystallites exhibit a tilt with respect to the substrate plane.
Theoretical Simulation of Vibrational Sum‐Frequency Generation Spectra from Density Functional Theory: Application to p‐Nitrothiophenol and 2,4‐Dinitroaniline
Authors: Guthmuller Julien , Cecchet Francesca , Lis Dan , Caudano Yves , Mani Alaa Addin , Thiry Paul A. , Peremans André , Champagne Benoît 
Published: June 2009

AbstractThe molecular orientation of adsorbed molecules forming self‐assembled monolayers can be determined by combining vibrational sum‐frequency generation (SFG) measurements with quantum chemical calculations. Herein, we present a theoretical methodology used to simulate the SFG spectra for different combinations of polarizations. These simulations are based on calculations of the IR vectors and Raman tensors, which are obtained from density functional theory computations. The dependency of the SFG vibrational signature with respect to the molecular orientation is presented for the molecules p‐nitrothiophenol and 2,4‐dinitroaniline. It is found that a suitable choice of basis set as well as of exchange‐correlation (XC) functional is mandatory to correctly simulate the SFG intensities and consequently provide an accurate estimation of the adsorbed molecule orientation. Comparison with experimental data shows that calculations performed at the B3LYP/6‐311++G(d,p) level of approximation provide good agreement with experimental frequencies, and with IR and Raman intensities. In particular, it is demonstrated that polarization and diffuse functions are compulsory for reproducing the IR and Raman spectra, and consequently vibrational SFG spectra, of systems such as p‐nitrothiophenol. Moreover, the investigated XC functionals reveal their influence on the relative intensities, which show rather systematic variations with the amount of Hartree–Fock exchange. Finally, further aspects of the modeling are revealed by considering the frequency dependence of the Raman tensors.
110 Years of the Meyer–Overton Rule: Predicting Membrane Permeability of Gases and Other Small Compounds
Authors: Missner Andreas , Pohl Peter 
Published: June 2009

AbstractThe transport of gaseous compounds across biological membranes (see picture) is essential in all forms of life. In this Minireview, the authors discuss recently reported violations of the well‐established Meyer–Overton rule for small molecules, including carboxylic acids and gases, and show that Meyer and Overton continue to rule.magnified imageThe transport of gaseous compounds across biological membranes is essential in all forms of life. Although it was generally accepted that gases freely penetrate the lipid matrix of biological membranes, a number of studies challenged this doctrine as they found biological membranes to have extremely low gas‐permeability values. These observations led to the identification of several membrane‐embedded “gas” channels, which facilitate the transport of biological active gases, such as carbon dioxide, nitric oxide, and ammonia. However, some of these findings are in contrast to the well‐established solubility–diffusion model (also known as the Meyer–Overton rule), which predicts membrane permeabilities from the molecule′s oil–water partition coefficient. Herein, we discuss recently reported violations of the Meyer–Overton rule for small molecules, including carboxylic acids and gases, and show that Meyer and Overton continue to rule.
A Force‐Spectroscopy‐Based Single‐Molecule Metal‐Binding Assay
Authors: Cao Yi , Er Kai Shih , Parhar Rakesh , Li Hongbin 
Published: June 2009

AbstractQuantifying metal‐binding by force:A quantitative single‐molecule force‐spectroscopy‐based assay is developed to measure the binding affinity of metal ions to proteins. The method uses the unfolding force of a protein as a direct probe to distinguish the apo and metal‐ion‐bound forms of that protein and quantify the partitioning between the two forms (see figure).magnified image
Cover Picture: Critical Size for O2 Dissociation by Au Nanoparticles (ChemPhysChem 2/2009)
Authors: Roldán Alberto , González Silvia , Ricart Josep Manel , Illas Francesc 
Published: June 2009

AbstractThe cover picture shows the results of a systematic density functional theory study of the intrinsic reactivity of unsupported Au nanoparticles towards molecular oxygen dissociation. The top part of the image evidences the prediction that small nanoparticles such as Au25 and Au38 are able to dissociate O2 through a small energy barrier. The middle part and bottom part of the image show the different behaviour of larger nanoparticles and of extended Au surfaces where impinging O2 molecules are likely to desorb. These results by F. Illas et al. (page 348) provide an explanation to recent findings (Turner et al. Nature, 2008, 454, 981) indicating that Au nanoparticles derived from Au55 are able to selectively oxidize styrene directly from dioxygen.magnified image
Adaptive secure multicast in wireless networks
Authors: Han Yiliang , Gui Xiaolin 
Published: June 2009

AbstractSecure multicast is one of the majority services in the near future. The frameworks for IP multicast cannot be directly applied in wireless networks. To address the natural issues of wireless multicast and enhance the efficiency, an adaptive secure multicast framework based on a new primitive calledmulti‐recipient generalized signcryptionand a multi‐recipient generalized signcryption scheme based on the gap Diffie–Hellman problem (MGSC‐GDH) are proposed. The key technologies to construct a high‐performance adaptive scheme including identification function, randomness reusing are investigated. The framework provides separate or joint encryption and signature functions according to users' identities and requirements transparently, and has the ability to aggregate multiple unicast besides the common multicast service. Therefore, overheads are reduced sharply for multiple functions which are provided with a single primitive. By the precise reduction, the gap‐bridge between the security of a base scheme and the corresponding multi‐recipient generalized signcryption scheme is built, which is a direct measure to quantify the security. Analysis shows that MGSC‐GDH is a semantic secure multi‐recipient generalized signcryption scheme and more efficient than other similar schemes in computational and communicational aspects. It is suitable for dynamic environment for rekeying is avoided when membership changes. Copyright © 2009 John Wiley & Sons, Ltd.
Disruption of the cytoskeleton during Semaphorin 3A induced growth cone collapse correlates with differences in actin organization and associated binding proteins
Authors: Brown Jacquelyn A. , Bridgman Paul C. 
Published: June 2009

AbstractRepulsive guidance cues induce growth cone collapse or collapse and retraction. Collapse results from disruption and loss of the actin cytoskeleton. Actin‐rich regions of growth cones contain binding proteins that influence filament organization, such as Arp2/3, cortactin, and fascin, but little is known about the role that these proteins play in collapse. Here, we show that Semaphorin 3A (Sema 3A), which is repulsive to mouse dorsal root ganglion neurons, has unequal effects on actin binding proteins and their associated filaments. The immunofluorescence staining intensity of Arp‐2 and cortactin decreases relative to total protein; whereas in unextracted growth cones fascin increases. Fascin and myosin IIB staining redistribute and show increased overlap. The degree of actin filament loss during collapse correlates with filament superstructures detected by rotary shadow electron microscopy. Collapse results in the loss of branched f‐actin meshworks, while actin bundles are partially retained to varying degrees. Taken together with the known affects of Sema 3A on actin, this suggests a model for collapse that follows a sequence; depolymerization of actin meshworks followed by partial depolymerization of fascin associated actin bundles and their movement to the neurite to complete collapse. The relocated fascin associated actin bundles may provide the substrate for actomyosin contractions that produce retraction. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009
Growth cone‐like waves transport actin and promote axonogenesis and neurite branching
Authors: Flynn Kevin C. , Pak Chi W. , Shaw Alisa E. , Bradke Frank , Bamburg James R. 
Published: June 2009

AbstractAxonogenesis involves a shift from uniform delivery of materials to all neurites to preferential delivery to the putative axon, supporting its more rapid extension. Waves, growth cone‐like structures that propagate down the length of neurites, were shown previously to correlate with neurite growth in dissociated cultured hippocampal neurons. Waves are similar to growth cones in their structure, composition and dynamics. Here, we report that waves form in all undifferentiated neurites, but occur more frequently in the future axon during initial neuronal polarization. Moreover, wave frequency and their impact on neurite growth are altered in neurons treated with stimuli that enhance axonogenesis. Coincident with wave arrival, growth cones enlarge and undergo a marked increase in dynamics. Through their engorgement of filopodia along the neurite shaft, waves can induce de novo neurite branching. Actin in waves maintains much of its cohesiveness during transport whereas actin in nonwave regions of the neurite rapidly diffuses as measured by live cell imaging of photoactivated GFP‐actin and photoconversion of Dendra‐actin. Thus, waves represent an alternative axonal transport mechanism for actin. Waves also occur in neurons in organotypic hippocampal slices where they propagate along neurites in the dentate gyrus and the CA regions and induce branching. Taken together, our results indicate that waves are physiologically relevant and contribute to axon growth and branching via the transport of actin and by increasing growth cone dynamics. © 2009 Wiley Periodicals, Inc. Develop Neurobiol 2009
A Fast Response Strontium Ion‐Selective Electrode Prepared by Sol‐Gel Membrane Technique
Authors: Zanjanchi M. A. , Arvand M. , Mahmoodi N. O. , Islamnezhad A. 
Published: June 2009

AbstractA sol‐gel electrode, based on 6‐(4‐nitrophenyl)‐2‐phenyl‐4,4‐dipropyl‐3,5‐diaza‐bicyclo [3,1,0] hex‐2‐ene (NPDBH) as a neutral ionophore, was successfully developed for the detection of Sr2+ in aqueous solutions. Theoretical calculations confirmed NPDBH selectivity toward strontium in comparison with some other metal ions. The electrode responds to Sr2+ ion with a sensitivity of 29.1±0.4 mV/decade over the range 8.0×10−7–1.0×10−1 M. Selectivity coefficients determined by matched potential method (MPM) indicate high selectivity for strontium ions. The electrode has a fast response time of 11 s and a working pH range of 3.0–10.0. The sol‐gel electrode shows detection limit of 7.5×10−8 M.
Characteristics of Voltammetric Determination and Speciation of Chromium – A Review
Authors: Bobrowski Andrzej , Królicka Agnieszka , Zarębski Jerzy 
Published: June 2009

AbstractThis article reviews the voltammetric methods of chromium determination, including adsorptive and catalytic adsorptive stripping voltammetry at liquid mercury, metallic films, and modified carbon paste electrodes. The principle applications of the catalytic adsorptive stripping voltammetric method of chromium(VI) determination in the presence of DTPA and nitrate, most useful in the analysis of chromium traces and its speciation, is presented in detail. Special emphasis is put on the presentation and characterization of the voltammetric procedures which make it possible to conduction speciation studies of chromium(VI) in the presence of a great excess of chromium(III) and surfactants. This survey is based on 173 articles.
A Simple and Sensitive Method for the Amperometric Detection of Trace Chromium(VI) Based on Prussian Blue Modified Glassy Carbon Electrode
Authors: Xing Sujie , Xu He , Shi Guoyue , Chen Junshui , Zeng Liping , Jin Litong 
Published: June 2009

AbstractA simple and sensitive method for the amperometric detection of trace amount of chromium(VI) using a Prussian blue modified glassy carbon electrode (PB/GCE) is described here. The Everitts salt/Prussian blue redox couple of the PB film was found to mediate the Cr(VI) reduction, and the mechanism of electrochemical reaction was investigated. The effects of PB film thickness, applied potential and electrolyte solution on the current response of Cr(VI) reduction were thoroughly studied. Under the optimized conditions, the PB/GCE provided a wide linear range for Cr(VI) analysis from 0.5 to 200 ppb with excellent sensitivity (15±0.2 nA/ppb) and low detection limit (0.15 ppb). In addition, the modified electrode showed excellent stability, reproducibility and good resistance to other metal ions and surfactants. Finally, the proposed method was applied to detect trace Cr(VI) in wastewater with satisfactory results. The great advantages of the method were characterized by the simplicity, ease of preparation, stability, short analysis time and cost‐efficiency.
A Microbial Sensor Based on Direct Electron Transfer at Shewanella Sp. Drop‐Coated Screen‐Printed Carbon Electrodes
Authors: Sudhakara Prasad Kariate , Arun A. B. , Rekha P. D. , Young Chiu‐Chung , Chang Jen‐Lin , Zen Jyh‐Myng 
Published: June 2009

AbstractAerobically grown Shewanella sp. bacterial suspension drop‐coated on a disposable screen‐printed carbon electrode was found to possess electroactivity without the aid of redox mediator. Cyclic voltammetric studies revealed the characteristics of a mixed diffusion adsorption‐controlled electrochemical process for direct electron transfer at the bacteria‐modified electrode. Both FE‐SEM and ATR FT‐IR experiments were carried out to investigate the surface characteristics. The electroanalytical applicability was further demonstrated for electrocatalytic reduction of arsenite, hydrogen peroxide and nitrite. Low cost and very simple manufacturing procedure allow for the proposed bacterial sensor to be applied as disposable devices.
Fifteen year comparison of antipsychotic use in people with dementia within hospital and nursing home settings: sequential cross‐sectional study
Authors: Connelly Peter J. , Law Emma , Angus Susan , Prentice Neil 
Published: June 2009

AbstractObjectiveThe use of antipsychotics to treat people with behavioural and psychological symptoms associated with dementia is controversial, especially in long‐stay settings. We assessed the relationship between behaviour, function and antipsychotic use in people with dementia in a long‐stay psychiatric unit and designated elderly mentally ill (EMI) nursing homes over a 15‐year period.MethodSequential cross‐sectional studies assessing twelve behaviours and seven measures of function for each patient. Antipsychotic and antidepressant use was obtained from current prescription records.ResultsRegular antipsychotic use in hospital fell between 1990 and 1998. In 1998 use in nursing homes was significantly greater than in hospital, and increased between 1998 and 2005. Noisiness/verbal aggression (NVA) was the only behaviour more commonly associated with regular antipsychotic use over that timescale. Those with low levels of core symptoms (p = 0.021) and high dependency patients (p = 0.001) were more likely to be receiving regular antipsychotics in nursing homes than in hospital. Depression was not treated well even when identified.ConclusionCompared to a long‐stay hospital setting, antipsychotic drug use for people with dementia in nursing homes has risen and become less systematic. This cannot be explained by increasing core behaviour symptoms or differences in physical dependency. Copyright © 2009 John Wiley & Sons, Ltd.
UCP2, a metabolic sensor coupling glucose oxidation to mitochondrial metabolism?
Authors: Pecqueur Claire , Alves‐Guerra Clotilde , Ricquier Daniel , Bouillaud Frederic 
Published: June 2009

AbstractMitochondrial uncoupling of oxidative phosphorylation may serve a variety of purposes such as the regulation of substrate oxidation, free radical production (a major by‐product of mitochondrial respiration) and ATP production and turnover. As regulators of energy expenditure and antioxidant defenses, uncoupling proteins would seem to offer an attractive mechanism by which to explain the control of body weight, resting metabolic rate and aging. As a result, the discovery of UCP1 homologues has led to an impressive number of publications. However, 10 years after their identification, no consensus has been found concerning the function of UCP homologues, and there are controversies as to whether or not they even have physiologically significant uncoupling activity. Here, we discuss a potential new function for UCP2, as a carrier involved in the coupling between glucose oxidation and mitochondrial metabolism. © 2009 IUBMB IUBMB Life 61(7): 762–767, 2009
Nuclear localization signals and human disease
Authors: McLane Laura M. , Corbett Anita H. 
Published: June 2009

AbstractIn eukaryotic cells, the physical separation of the genetic material in the nucleus from the translation and signaling machinery in the cytoplasm by the nuclear envelope creates a requirement for a mechanism through which macromolecules can enter or exit the nucleus as necessary. Nucleocytoplasmic transport involves the specific recognition of cargo molecules by transport receptors in one compartment followed by the physical relocation of that cargo into the other compartment through regulated pores that perforate the nuclear envelope. The recognition of protein cargoes by their transport receptors occurs via amino acid sequences in cargo proteins called nuclear targeting signals. Both nuclear import and export of proteins are highly regulated processes that control, not only what cargo can enter and/or exit the nucleus, but also when in the cell cycle and in what cell type, the cargo can be transported. Deregulation of the nuclear transport of specific cargoes has been linked to numerous cancers and developmental disorders highlighting the importance of understanding the mechanisms underlying nucleocytoplasmic transport and particularly the modulation of the specific interactions between transporter receptors and nuclear targeting signals within target cargo proteins. © 2009 IUBMB IUBMB Life 61(7): 697–706, 2009