bluuebunny/crossref_metadata_2025_split huggingface dataset:
Surgical management of the tethered spinal cord—walking the fine line
Authors: Drake James M. 
Published: April 2011

✓The tethered spinal cord is a fascinating yet controversial condition seen frequently in neurosurgical practice. Treatment decision making is made difficult by the variety of lesions and clinical presentations comprised by this condition and the absence of high-quality clinical outcome data to provide guidance. Clinical presentations may be divided into four general categories or typical scenarios: 1) significant dysraphic abnormality, clear clinical deterioration; 2) significant dysraphic abnormality, clinically normal or stable deficit; 3) incidentally discovered abnormality, other problem; and 4) tethered spinal cord symptomatology, normal imaging. The author provides case examples to illustrate potential treatment approaches and suggests balancing the risks and benefits for each general category.
Clearer diagnostic and treatment strategies for the tethered spinal cord will only result from high-quality clinical and basic research. Until the results of such research are available, surgeons should endeavor to maximize benefit and reduce risk for patients who may have a tethered spinal cord, walking the fine line between over- and undertreatment.
Maternal Outcomes after Haart for the Prevention of Mother-To-Child Transmission in HIV-Infected Women in Brazil
Authors: Pilotto Jose H , Velasque Luciane S , Friedman Ruth K , Moreira Ronaldo I , Veloso Valdilea G , Grinsztejn Beatriz , Morgado Mariza G , Watts D Heather , Currier Judith S , Hoffman Risa M 
Published: April 2011

Background Information is lacking on outcomes in HIV-infected Brazilian women with CD4+ T-cell counts >200 cells/mm3 who initiate HAART for the prevention of mother-to-child transmission, and discontinue after delivery. Methods Clinical event rates after postpartum HAART discontinuation were calculated for all WHO stage 2–3 events, as well as for HIV progression warranting HAART re-initiation, defined by a WHO stage 4 event and/or CD4+ T-cell decrease to ≤200 cells/mm3. Predictors of the WHO stage 2–3 events and HIV progression outcomes were evaluated with Cox's proportional hazards models. Results A total of 120 women were followed for a mean of 1.5 years after delivery. Overall, 26 women had 30 events as follows: 20 developed WHO stage 2–3 events, yielding an incidence rate of 13/100 person-years (PY; 95% CI 8–20); 10 developed HIV progression requiring HAART re-initiation (incidence ratio 6/100 PY, 95% CI 3–11). Among progressors, a single woman developed a WHO stage 4 clinical event and the remainder had CD4+ T-cell decreases. Women who had baseline CD4+ T-cell counts between 200–500 cells/mm3 had a hazard ratio for WHO stage 2–3 events of 2.5 compared to women with baseline ≥500 cells/mm3 (95% CI 1.0–6.3; P=0.05). The only significant predictor of HIV progression was baseline CD4+ T-cell count (hazard ratio 0.99, 95% CI 0.98–0.99; P=0.02). Conclusions In this observational study, a baseline CD4+ T-cell count <500 cells/mm3 was associated with an increased risk of postpartum WHO stage 2–3 clinical events and HIV disease progression. Randomized studies are needed to further evaluate the effect of postpartum treatment discontinuation on maternal health.
Maturité des crédits bancaires et performance des entreprises : cas du Cameroun
Authors: Tioumagneng André 
Published: April 2011

L’offre insuffisante des crédits bancaires de long terme est considérée comme la contrainte au développement des entreprises camerounaises. Les travaux empiriques sur le sujet sont cependant rares. Cet article cherche à déterminer l’impact des dettes bancaires de long terme sur la performance des entreprises. L’échantillon est composé de 99 entreprises camerounaises et les données sont celles de la période 2001-2005. Les résultats montrent que les dettes bancaires défavorisent la performance. Ils invitent à réfléchir sur les leviers d’action nécessaires pour rendre les banques relationnelles dans leur rapport de crédit.
Moderniser l'Etat : les aspects financiers des programme reviews au Royaume-Uni
Authors: Lapsley Irvine , Midwinter Arthur 
Published: April 2011

Le présent article étudie le phénomène de la Revue globale des dépenses publiques ( CSR , ou Comprehensive spending review) au Royaume-Uni. Il montre que cette CSR a été au cœur de la modernisation de l’État défendue par le gouvernement travailliste élu en 1997 et resté en fonctions jusqu’en mai 2010. La CSR a été introduite en 1998 dans le cadre des politiques de modernisation voulues par le New Labour. Son histoire est empreinte de continuité et de changements. Les idées de la Nouvelle Gestion Publique, portées par les gouvernements conservateurs au pouvoir entre 1979 et 1997, imprègnent de manière évidente les innovations apportées par la CSR . Le gouvernement de coalition élu en 2010 au Royaume-Uni a cherché à prendre ses distances par rapport au gouvernement précédent en décidant une refonte de la Revue des dépenses publiques. D’importantes similitudes subsistent cependant. Un ancien régime a certes été désavoué mais a en fait été perfectionné.
L'hybridation du modèle territorial français.
Authors: Bezes Philippe , Le Lidec Patrick 
Published: April 2011

Cet article analyse la réforme de l’administration territoriale de l’État (dite RÉATE), menée dans le cadre de la révision générale des politiques publiques (RGPP). D’une ampleur sans précédent depuis la réforme de 1964, la réorganisation affecte aussi bien la division du travail entre les différentes composantes des services déconcentrés que les relations hiérarchiques entre les administrations centrales, régionales et départementales. Marque-t-elle pour autant un véritable tournant réformateur que rien ne laissait présager ou s’inscrit-elle, au contraire, dans la continuité de réformes antérieures ? Cet article propose de faire le départ entre des dynamiques de reproduction institutionnelle et des dynamiques de changement. La thèse défendue est double. L’article montre, d’une part, que la RGPP a constitué un cadre opportun pour relancer et ampliﬁer une réforme de l’administration territoriale déjà engagée depuis 2002. Le processus conflictuel d’élaboration de la nouvelle forme débouche, d’autre part, sur un compromis qui hybride de manière originale l’organisation historique de l’administration territoriale de l’État.
L'impact de la RGPP sur le contrôle de légalité
Authors: Bricault Jean-Michel 
Published: April 2011

« Mission constitutionnelle du représentant de l’État dans les collectivités territoriales de la Républiques » en vertu de l’article 72 de la Constitution, le contrôle de légalité est particulièrement affecté par la RGPP. Stratégie locale de contrôle, tentative d’initiation d’un travail en réseau, essai de polarisation du contrôle sur les actes locaux les plus sensibles et nouvel allègement de la liste des actes soumis à l’obligation de transmission, le tout pour pallier les carences en personnel qualiﬁé ; tels sont les « remèdes » de la RGPP pour tenter d’améliorer le « bilan de santé » du contrôle de légalité. Pour autant que ces objectifs soient louables, il n’est pas certain que cela suffise à rétablir un meilleur équilibre au proﬁt du contrôle de légalité.
Efficient Addition Reaction of Dibutylphosphane Oxide with Alkynes: New Mechanistic Proposal Involving a Duo of Palladium and Brønsted Acid
Authors: Kanada Jun , Tanaka Masato 
Published: April 2011

AbstractThe addition reaction of dibutylphosphane oxide [Bu2P(O)H] with alkynes proceeds efficiently in the presence of palladium‐chelating phosphane–Brønsted acid catalyst systems. Terminal alkynes afford branched‐structured products selectively. On the other hand, the same reaction using monodentate phosphane ligands or the reaction run in the absence of a Brønsted acid affords a much lower yield. A mechanistic study has revealed that Brønsted acids (XOH) interact with oxygen in MP(O)R2 species (M=Pd, Pt) through hydrogen bonding to transform them to ionic M+←PR2(OH⋅⋅⋅O−X) species, which was confirmed by NMR spectroscopy and X‐ray crystallography. The phosphane‐like PR2(OH⋅⋅⋅O−X) moiety is coordinatively labile, as substantiated by the ligand exchange reaction with tert‐butyl isocyanide. A new mechanism that accommodates these observations has been proposed to rationalize the enhancement of catalytic activity and the regioselectivity induced by the Brønsted acid.
Asymmetric Epoxidation of α,β‐Unsaturated Aldehydes in Aqueous Media Catalyzed by Resin‐Supported Peptide‐ Containing Unnatural Amino Acids
Authors: Akagawa Kengo , Kudo Kazuaki 
Published: April 2011

AbstractThe enantio‐ and diastereoselective epoxidation of α,β‐unsaturated aldehydes in aqueous media was realized using a resin‐supported peptide catalyst. Introducing the hydrophobic and bulky unnatural amino acid 3‐(1‐pyrenyl)alanine into the peptide sequence was effective for enhancing the reaction rate and enantioselectivity.
Bis‐Sulfamyl Imines: Potent Substrates for Asymmetric Additions of Arylboroxines under Rhodium Catalysis
Authors: Crampton Rosemary , Woodward Simon , Fox Martin 
Published: April 2011

AbstractBis‐sulfamyl imines are shown to be potentially ideal substrates for rhodium‐catalysed asymmetric additions of arylboron nucleophiles as they show: (i) near perfect enantioselectivities (11 examples, 98–99+% ee), (ii) good to excellent diastereoselectivities (10–32:1 rac:meso), and (iii) high functional group tolerance in removal of the low molecular weight protecting group via mild heating in aqueous pyridine.
Asymmetric Carbon‐Carbon Bond Forming Reactions Catalysed by Metal(II) Bis(oxazoline) Complexes Immobilized using Supported Ionic Liquids
Authors: Goodrich P. , Hardacre C. , Paun C. , Ribeiro A. , Kennedy S. , Lourenço M. J. V. , Manyar H. , de Castro C. A. Nieto , Besnea M. , Pârvulescu V. I. 
Published: April 2011

AbstractA series of bis(oxazoline) metal(II) complexes has been supported on silica and carbon supports by non‐covalent immobilisation using an ionic liquid. The catalytic performance of these solids was compared for the enantioselective Diels–Alder reaction between N‐acryloyloxazolidinone and cyclopentadiene and the Mukaiyama‐aldol reaction between methyl pyruvate and 1‐methoxy‐1‐trimethylsilyloxypropene. In both reactions the enantioselectivity was strongly influenced by the choice of support displaying enantioselectivies (ee values) up to 40% higher than those conducted under homogeneous reaction conditions.
Bipolar polymer semiconductor blends of C60‐end‐capped poly(4‐diphenylaminostyrene) and poly(4‐diphenylaminostyrene): One‐pot synthesis and charge‐transport properties
Authors: Natori Itaru , Natori Shizue , Sekikawa Hiroyuki , Takahashi Tomoyuki , Sato Hisaya 
Published: April 2011

AbstractThree types of fullerene (C60)‐end‐capped poly(4‐diphenylaminostyrene) (C60–PDAS) and poly(4‐diphenylaminostyrene) (PDAS) blends were prepared to investigate their potential as bipolar polymer semiconductors. The concentration of C60 in the C60–PDAS/PDAS blends strongly affected the hole and electron drift mobility values; the hole drift mobility decreased with an increase in the C60 concentration. However, the electron drift mobility increased with an increase in the C60 concentration. The hole and electron drift mobility values were almost the same for the 1/2 C60–PDAS/PDAS blend; therefore, this polymer blend was thought to be a bipolar polymer semiconductor. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Construction of novel brain‐targeting gene delivery system by natural magnetic nanoparticles
Authors: Han Lei , Zhang Anling , Wang Hanjie , Pu Peiyu , Kang Chunsheng , Chang Jin 
Published: April 2011

AbstractThe main objective in gene therapy of brain tumors is to develop efficient, low toxic, and brain‐targeting gene delivery systems which can cross the blood‐brain barrier (BBB) and deliver therapeutic gene to the brain cancerous tissues. In this study, we designed and constructed a novel gene delivery systems (Tat‐MS‐PAMAM) by modifying the magnetosome (MS) with polyamidoamine (PAMAM) dendrimers and Tat peptides for the first time. Tat‐MS‐PAMAM readily formed polyplexes with the luciferase reporter plasmid (pGL‐3) and improved plasmid complexation and stability against polyanion and DNase I. Transfection efficiencies of Tat‐MS‐PAMAM polyplexes with pGL‐3 were studied using U251 human glioma cells in vitro. The result showed that the incorporation of external magnetic field and Tat peptides could significantly improve transfection efficiency of delivery system. Furthermore, biodistribution in vivo demonstrated that Tat‐MS‐PAMAM could efficiently transport across the BBB and assemble at brain tissue of rat detected by single photo emission computed tomography. Thus, with the multifunction of magnetic targeting, BBB transporting, and efficient gene transfecting, Tat‐MS‐PAMAM might be a novel nonviral delivery system for gene therapy of brain tumors. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
A carboxylic acid‐functionalized polyfluorene as fluorescent probe for protein sensing
Authors: Wang Guojie , Wang Yani , Bao Biqing , Dong Jie , Zhang Jian , Wang Lianhui , Yang Huai , Zhan Xiaowei 
Published: April 2011

AbstractA new water‐soluble fluorescent conjugated polyelectrolyte, poly[9,9‐bis(3′‐butyrate)fluoren‐2,7‐yl] sodium (BBS‐PF), was studied as a fluorescent probe for protein sensing. The conjugated polyelectrolyte BBS‐PF shows high fluorescence sensitivity to cytochrome c, lysozyme, and bovine serum albumin (BSA). The Stern–Volmer constant (Ksv) in cytochrome c was measured to be as high as 6.1 × 107 L/mol, approximately twice as that of the other two. Interestingly, it is found that BSA slightly enhances the fluorescence of BBS‐PF rather than quenches the fluorescence at its micromolar concentrations. The excitation spectra confirm that the interaction of BBS‐PF with the proteins could be different. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Variations in the microstructure of carbon fibers prepared from liquefied wood during carbonization
Authors: Ma Xiaojun , Zhao Guangjie 
Published: April 2011

AbstractAfter spinning by adding hexamethylenetetramine and the curing treatment, carbon fibers from liquefied wood (LWCFs) were prepared by direct carbonization. Microstructure change of LWCFs during carbonization is studied by X‐ray, Raman spectroscopy, and FTIR. Raman spectroscopy shows both the D peak at 1360 cm−1 and the G peak at 1595 cm−1 exist after 600°C, and a significant decrease is found in ID/IG during carbonization. X‐ray diffraction shows the crystallite size (Lc(002) and La(100)) of LWCFs firstly decreases before 800°C and then increases with heat treatment temperature (HTT) increasing, whereas the interlayer spacing (d002) gradually decreases during carbonization. It is also found that the crystallite shape (La/Lc) and the degree of graphitization (G) all increase with increasing HTT. It is also found that structure of the precursor fibers from liquefied wood has been completely changed after carbonization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Polymer dynamics in epoxy/alumina nanocomposites studied by various techniques
Authors: Kyritsis Apostolos , Vikelis Georgios , Maroulas Panayiotis , Pissis Polycarpos , Milosheva Boryana , Kotsilkova Rumiana , Toplijska Antonia , Silvestre Clara , Duraccio Donatella 
Published: April 2011

AbstractEpoxy/alumina nanocomposites of various compositions were prepared by dispersing modified and nonmodified boehmite nanoparticles in diglycidyl ether of bisphenol‐A using diethylenetriamine as curing agent. Measurements of the viscosity of the nanodispersions provided information on particle–particle and particle–resin interactions. The structure of the nanocomposites was studied by scanning electron microscopy on fractured samples. Effects of nanoparticles on polymer dynamics was studied in detail by dynamic mechanical thermal analysis and two dielectric techniques, broadband dielectric relaxation spectroscopy and thermally stimulated depolarization currents. Three secondary relaxations, γ, β, and ω, the segmental α relaxation associated with the glass transition, and an interfacial relaxation, in the order of increasing frequency/decreasing temperature, were observed and studied. A correlation between viscosity (of the nanodispersions), storage modulus, glass transition temperature, real part of dielectric permittivity, and ductility of the nanocomposites was observed. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Highly sensitive method for the determination of adenosine by LC‐MS/MS‐ESI: method validation and scope of application to a pharmacokinetic/pharmacodynamic study
Authors: Sharma Kuldeep , Singh Radheraman , Giri Sanjeev , Rajagopal Sriram , Mullangi Ramesh 
Published: April 2011

ABSTRACTA highly sensitive, rapid assay method has been developed and validated for the estimation of adenosine in rat plasma with liquid chromatography coupled to tandem mass spectrometry with electro‐spray ionization in the positive‐ion mode. The assay procedure involves extraction of adenosine and phenacetin (internal standard, IS) from rat plasma with a simple protein precipitation extraction process. The method was validated using rat plasma with extinguished adenosine endogenous levels. Chromatographic separation was achieved using a binary gradient using mobile phase A (acetonitrile) and B (0.2% formic acid in water) at a flow rate of 0.50 mL/min on an Atlantis dC18 column with a total run time of 4.0 min. The MS/MS ion transitions monitored were 268 → 136 for adenosine and 180 → 110 for IS. Method validation was performed as per FDA guidelines and the results met the acceptance criteria. The lower limit of quantitation achieved was 0.48 ng/mL and the linearity range extended from 0.48 to 1210 ng/mL. The intra‐ and inter‐day precisions were in the ranges 2.32–12.7 and 4.01–9.40%, respectively. Copyright © 2011 John Wiley & Sons, Ltd.
Thiolate Chemistry: A Powerful and Versatile Synthetic Tool for Immobilization/Functionalization of Oligothiophenes on a Gold Surface
Authors: Tran Truong Khoa , Bricaud Quentin , Oçafrain Maïténa , Blanchard Philippe , Roncali Jean , Lenfant Stéphane , Godey Sylvie , Vuillaume Dominique , Rondeau David 
Published: April 2011

AbstractThe synthesis and characterization of a series of quaterthiophenes (4Ts) with thiolate groups protected with 2‐cyanoethyl (CNE), 2‐trimethylsilylethyl (TMSE), and acetyl (Ac) groups are described. Sequential cleavage of these different protecting groups allows for the preparation of 4Ts derivatized with ferrocene and/or alkanethiol chains. The electrochemical behavior of these compounds has been analyzed in solution by cyclic voltammetry (CV). A ferrocene‐derivatized dithiol 4T14and a dithiol 4T15with two TMSE‐protected thiolate groups have been immobilized on a gold surface as monolayers that have been characterized by CV, ellipsometry, contact‐angle measurement, and X‐ray photoelectron spectroscopy (XPS). The results show that molecules14and15are doubly grafted with a horizontal orientation of the conjugated system relative to the surface. Furthermore, application of the deprotection/alkylation sequence of the remaining protected thiolate groups on a monolayer of15allows for efficient post‐functionalization.
Relationship between auditory thresholds, central spontaneous activity, and hair cell loss after acoustic trauma
Authors: Mulders W.H.A.M. , Ding D. , Salvi R. , Robertson D. 
Published: April 2011

AbstractAcoustic trauma caused by exposure to a very loud sound increases spontaneous activity in central auditory structures such as the inferior colliculus. This hyperactivity has been suggested as a neural substrate for tinnitus, a phantom hearing sensation. In previous studies we have described a tentative link between the frequency region of hearing impairment and the corresponding tonotopic regions in the inferior colliculus showing hyperactivity. In this study we further investigated the relationship between cochlear compound action potential threshold loss, cochlear outer and inner hair cell loss, and central hyperactivity in inferior colliculus of guinea pigs. Two weeks after a 10‐kHz pure tone acoustic trauma, a tight relationship was demonstrated between the frequency region of compound action potential threshold loss and frequency regions in the inferior colliculus showing hyperactivity. Extending the duration of the acoustic trauma from 1 to 2 hours did not result in significant increases in final cochlear threshold loss, but did result in a further increase of spontaneous firing rates in the inferior colliculus. Interestingly, hair cell loss was not present in the frequency regions where elevated cochlear thresholds and central hyperactivity were measured, suggesting that subtle changes in hair cell or primary afferent neural function are sufficient for central hyperactivity to be triggered and maintained. J. Comp. Neurol. 519:2637–2647, 2011. © 2011 Wiley‐Liss, Inc.
PCP4 (PEP19) overexpression induces premature neuronal differentiation associated with Ca2+/Calmodulin‐Dependent kinase II‐δ activation in mouse models of down syndrome
Authors: Mouton‐Liger François , Thomas Sophie , Rattenbach Revital , Magnol Laetitia , Larigaldie Vanessa , Ledru Aurelie , Herault Yann , Verney Catherine , Créau Nicole 
Published: April 2011

AbstractPcp4/pep19 is a modulator of Ca2+‐CaM, a key molecule for calcium signaling, expressed in postmitotic neuroectoderm cells during mouse embryogenesis. The PCP4 gene is located on human chromosome 21 and is present in three copies in Down syndrome (DS). To evaluate the consequences of three copies of this gene on the development of these cells in the nervous system, we constructed a transgenic (TgPCP4) mouse model, with one copy of human PCP4, and investigated the effects in this model and in the Ts1Cje, a mouse model of DS. During embryogenesis, we analyzed 1) the level of pcp4 transcript and protein in the two models; 2) the extent of colabeling for markers of neuronal differentiation (βIII‐tubulin, Map2c, calbindin, and calretinin) and pcp4 by immunofluorescence analysis and overall protein levels of these markers by Western blotting; and 3) the rate of activation of CaMKII, a Ca2+‐CaM target, to evaluate the impact of pcp4 overexpression on the Ca2+‐CaM signaling pathway. We showed that three copies of the pcp4 gene induced the overexpression of transcripts and proteins during embryogenesis. Pcp4 overexpression 1) induced precocious neuronal differentiation, as shown by the distribution and levels of early neuronal markers; and 2) was associated with an increase in CaMKIIδ activation, confirming involvement in neuronal differentiation in vivo via a Pcp4−Ca2+−CaM pathway. TgPCP4 and Ts1Cje mice developed similar modifications, demonstrating that these mechanisms may account for abnormal neuronal development in DS. J. Comp. Neurol. 519:2779–2802, 2011. © 2011 Wiley‐Liss, Inc.