bluuebunny/crossref_metadata_2025_split huggingface dataset:
Randomized clinical trial comparing regional and general anaesthesia in minimally invasive video-assisted parathyroidectomy
Authors: Miccoli P , Barellini L , Monchik J M , Rago R , Berti P F 
Published: June 2005

Abstract

Background
This randomized clinical trial was performed in a single institution to compare the results of minimally invasive video-assisted parathyroidectomy (MIVAP) conducted under regional anaesthesia (RA) or general anaesthesia (GA).

Methods
Fifty-one patients undergoing MIVAP for primary hyperparathyroidism were assigned randomly to either RA (26 patients) or GA (25). RA involved a bilateral deep cervical block, and local infiltration of the incision site with a mixture of 0·25 per cent lignocaine and 0·15 per cent bupivacaine. GA was induced by intravenous administration of propofol, remifentanil and rocuronium bromide.

Results
The two groups were matched for age, sex, adenoma size, and preoperative serum calcium and parathyroid hormone levels. The interval from skin incision to closure was similar in the two groups (27·6 and 25·8 min for RA and GA respectively), whereas the total operating time (from induction of anaesthesia to return to the ward) was significantly lower with RA (72·1 versus 90·2 min; P = 0·001). The postoperative requirement for pain medication, measured in terms of amount of ketorolac administered at the request of the patient, was significantly lower in the RA group (28·5 versus 80 mg/day; P &lt; 0·001).

Conclusion
MIVAP performed under RA was associated with a shorter overall operating time and a reduced need for postoperative pain relief.
Electronic structure of Zn‐chlorin π‐anions studied by spectroscopic and quantum‐chemical methods
Authors: Shulga A. M. , Sinyakov G. N. , Filatov I. V. , Gurinovich G. P. , Dzilinski K. 
Published: May 2005

AbstractElectronic structure of neutral Zn‐chlorin complexes and their π‐mono‐ and dianions has been considered. The π‐anions were obtained by reduction of neutral chlorins with a sodium mirror in tetrahydrofuran solution. Results of spectroscopic studies have been compared with semiempirical quantum‐chemical calculations. Characteristic bands in electronic absorption spectra of the uv, visible and near infrared regions are in good agreement with CNDO/S‐CI calculations. Partially resolved hyperfine structure in EPR spectra of π‐radical anions was observed. Parameters of the EPR spectra obtained by using the simulation technique were compared with spin densities calculated by the INDO method. The detailed interpretation of 1H and 13C NMR spectra of neutral and dianion Zn‐octaethylchlorins is presented. All the proton signals in π‐dianions are shifted upfield because of the influence of paramagnetic ring current. The upfield shifts in 13C NMR spectra of the species studied have been observed too, except for two carbon atoms of the pyrrole ring being placed opposite the hydrogenated one. The 13C peak positions correlate with the charge distribution on C atoms in neutral molecules as well as in π‐dianions. © 1995 John Wiley & Sons, Inc.
Water Cluster Growth in Hydrophobic Solid Nanospaces
Authors: Ohba Tomonori , Kanoh Hirofumi , Kaneko Katsumi 
Published: June 2005

AbstractThe growth mechanism of water clusters in carbon nanopores is clearly elucidated by in situ small‐angle X‐ray scattering (SAXS) studies and grand canonical Monte Carlo (GCMC) simulations at 293–313 K. Water molecules are isolated from each other in hydrophobic nanopores below relative pressures (P/P0) of 0.5. Water molecules associate with each other to form clusters of about 0.6 nm in size at P/P0=0.6, accompanied by a remarkable aggregation of these clusters. The complete filling of carbon nanopores finishes at about P/P0=0.8. The correlation length analysis of SAXS profiles leads to the proposal of a growth mechanism for these water clusters and the presence of the critical cluster size of 0.6 nm leads to extremely stable clusters of water molecules in hydrophobic nanopores. Once a cluster of the critical size is formed in hydrophobic nanopores, the predominant water adsorption begins to fill carbon nanopores.
Gadolinium(III)‐Loaded Nanoparticulate Zeolites as Potential High‐Field MRI Contrast Agents: Relationship Between Structure and Relaxivity
Authors: Csajbók Éva , Bányai István , Vander Elst Luce , Muller Robert N. , Zhou Wuzong , Peters Joop A. 
Published: June 2005

AbstractThe effects of dealumination, pore size, and calcination on the efficiency (as expressed in the relaxivity) of Gd3+‐loaded zeolites for potential application as magnetic resonance imaging (MRI) contrast agents were studied. Partial dealumination of zeolites NaY or NaA by treatment with (NH4)2SiF6 or diluted HCl resulted in materials that, upon loading with Gd3+, had a much higher relaxivity than the corresponding non‐dealuminated materials. Analysis of the 1H NMR dispersion profiles of the various zeolites showed that this can be mainly ascribed to an increase of the amount of water inside the zeolite cavities as a result of the destruction of walls between cavities. However, the average residence time of water inside the Gd3+‐loaded cavities did not change significantly, which suggests that the windows of the Gd3+‐loaded cavities are not affected by the dealumination. Upon calcination, the Gd3+ ions moved to the small sodalite cavities and became less accessible for water, resulting in a decrease in relaxivity. The important role of diffusion for the relaxivity was demonstrated by a comparison of the relaxivity of Gd3+‐loaded zeolite NaY and NaA samples. NaA had much lower relaxivities due to the smaller pore sizes. The transversal relaxivities of the Gd3+‐doped zeolites are comparable in magnitude to the longitudinal ones at low magnetic fields (<60 MHz). However at higher fields, the transversal relaxivities steeply increased, whereas the longitudinal relaxivities decreased as field strength increased. Therefore, these materials have potential as T1 MRI contrast agents at low field, and as T2 agents at higher fields.
Probing Molecular Wires: Synthesis, Structural, and Electronic Study of Donor–Acceptor Assemblies Exhibiting Long‐Range Electron Transfer
Authors: Giacalone Francesco , Segura José L. , Martín Nazario , Ramey Jeff , Guldi Dirk M. 
Published: June 2005

AbstractA series of donor–acceptor arrays (C60–oligo‐PPV–exTTF; 16–20) incorporating π‐conjugated oligo(phenylenevinylene) wires (oligo‐PPV) of different length between π‐extended tetrathiafulvalene (exTTF) as electron donor and C60 as electron acceptor has been prepared by multistep convergent synthetic approaches. The electronic interactions between the three electroactive species present in 16–20 were investigated by UV‐visible spectroscopy and cyclic voltammetry (CV). Our studies clearly show that, although the C60 units are connected to the exTTF donors through a π‐conjugated oligo‐PPV framework, no significant electronic interactions are observed in the ground state. Interestingly, photoinduced electron‐transfer processes over distances of up to 50 Å afford highly stabilized radical ion pairs. The measured lifetimes for the photogenerated charge‐separated states are in the range of hundreds of nanoseconds (∼500 ns) in benzonitrile, regardless of the oligomer length (i.e., from the monomer to the pentamer). A different lifetime (4.35 μs) is observed for the heptamer‐containing array. This difference in lifetime has been accounted for by the loss of planarity of the oPPV moiety that increases with the wire length, as established by semi‐empirical (PM3) theoretical calculations carried out with 19 and 20. The charge recombination dynamics reveal a very low attenuation factor (β=0.01±0.005 Å−1). This β value, as well as the strong electron coupling (V∼5.5 cm−1) between the donor and the acceptor units, clearly reveals a nanowire behavior for the π‐conjugated oligomer, which paves the way for applications in nanotechnology.
Amino Acid Catalyzed Neogenesis of Carbohydrates: A Plausible Ancient Transformation
Authors: Córdova Armando , Ibrahem Ismail , Casas Jesús , Sundén Henrik , Engqvist Magnus , Reyes Efraim 
Published: June 2005

AbstractHexose sugars play a fundamental role in vital biochemical processes and their biosynthesis is achieved through enzyme‐catalyzed pathways. Herein we disclose the ability of amino acids to catalyze the asymmetric neogenesis of carbohydrates by sequential cross‐aldol reactions. The amino acids mediate the asymmetric de novo synthesis of natural L‐ and D‐hexoses and their analogues with excellent stereoselectivity in organic solvents. In some cases, the four new stereocenters are assembled with almost absolute stereocontrol. The unique feature of these results is that, when an amino acid is employed as the catalyst, a single reaction sequence can convert a protected glycol aldehyde into a hexose in one step. For example, proline and its derivatives catalyze the asymmetric neogenesis of allose with >99 % ee in one chemical manipulation. Furthermore, all amino acids tested catalyzed the asymmetric formation of natural sugars under prebiotic conditions, with alanine being the smallest catalyst. The inherent simplicity of this catalytic process suggests that a catalytic prebiotic “gluconeogenesis” may occur, in which amino acids transfer their stereochemical information to sugars. In addition, the amino acid catalyzed stereoselective sequential cross‐aldol reactions were performed as a two‐step procedure with different aldehydes as acceptors and nucleophiles. The employment of two different amino acids as catalysts for the iterative direct aldol reactions enabled the asymmetric synthesis of deoxysugars with >99 % ee. In addition, the direct amino acid catalyzed C2+C2+C2 methodology is a new entry for the short, highly enantioselective de novo synthesis of carbohydrate derivatives, isotope‐labeled sugars, and polyketide natural products. The one‐pot asymmetric de novo syntheses of deoxy and polyketide carbohydrates involved a novel dynamic kinetic asymmetric transformation (DYKAT) mediated by an amino acid.
Cooperative Recognition of C60–Ammonium Substrates by a Ditopic Oligophenylenevinylene/Crown Ether Host
Authors: Elhabiri Mourad , Trabolsi Ali , Cardinali François , Hahn Uwe , Albrecht‐Gary Anne‐Marie , Nierengarten Jean‐François 
Published: June 2005

AbstractA new fullerene derivative with an ammonium subunit has been prepared. Its ability to form supramolecular complexes with oligophenylenevinylene derivatives bearing one or two crown ether moieties has been evidenced by electrospray mass spectrometry, and UV‐visible and luminescence spectroscopy experiments. Interestingly, the assembly of the C60–ammonium cation with the oligophenylenevinylene derivative bearing two crown ether moieties leads to the cooperative formation of the 2:1 complex owing to intramolecular fullerene–fullerene interactions.
Immunomodulation with interferon‐gamma and colony‐stimulating factors for refractory fungal infections in patients with leukemia
Authors: Dignani M. Cecilia , Rex John H. , Chan Ka‐Wah , Dow Gordon , deMagalhaes‐Silverman Margarida , Maddox AnneMarie , Walsh Thomas , Anaissie Elias 
Published: June 2005

AbstractBACKGROUNDInvasive fungal infections (IFI) in immunocompromised patients are associated with significant morbidity and mortality, despite appropriate antifungal treatment and recovery from neutropenia. The outcome of these infections depends significantly on the overall state of immunosuppression, including mainly the phagocytic system (neutrophils and macrophages). Interferon‐gamma (IFN‐γ), granulocyte‐colony—stimulating factor (G‐CSF) and granulocyte‐macrophage—colony‐stimulating factor (GM‐CSF) are cytokines that enhance the activity of neutrophils and macrophages.METHODSThe authors reported 4 patients with leukemia and refractory invasive candidiasis or trichosporonosis despite 1–13 months of appropriate antifungal treatment.RESULTSCytokines were administered for 1.5–5 months without significant toxicity. For each patient, initiation of interferon‐gamma plus a colony‐stimulating factor resulted in a clinical response. The contribution of cytokines to control the fungal infection in these 4 patients was suggested by the strong inflammatory reaction observed in the 2 patients who had an immediate response (within 7 days of initiation of cytokine therapy) and by the good outcome in the 2 other patients in whom antifungal agents were discontinued at the start of cytokine therapy.CONCLUSIONSThese data suggested a potential role for immunomodulation in patients with leukemia with refractory invasive fungal infections. Cancer 2005. Published 2005 by the American Cancer Society.
Bis(salicylaldiminato)titanium Complexes Containing Bulky Imine Substituents: Synthesis, Characterization and Ethene Polymerization Studies
Authors: Pärssinen Antti , Luhtanen Tommi , Klinga Martti , Pakkanen Tapani , Leskelä Markku , Repo Timo 
Published: June 2005

AbstractA series of titanium complexes bearing two anionic [N, O–] bidentate salicylaldiminato ligands, namely bis[(N‐salicylidene)anilinato]titanium(IV) dichloride (1), bis[(N‐salicylidene)‐2,6‐dimethylanilinato]titanium(IV) dichloride (2), bis[(N‐salicylidene)‐2,6‐di‐i‐ propylanilinato]titanium(IV) dichloride (3), bis[(N‐salicylidene)‐(1‐naphthalenylimino)]titanium(IV) dichloride (4), bis[(N‐salicylidene)‐2,6‐difluoroanilinato]titanium(IV) dichloride (5), and bis[(N‐3‐fluorosalicylidene)‐2,6‐difluoroanilinato]titanium(IV) dichloride (6) have been synthesized with good yields by a two‐step procedure. The X‐ray structure analysis reveals that in complex 2, titanium has a distorted octahedral coordination sphere in which the oxygen atoms and the chloride ligands form the basal plane. Both the chloride and the phenoxy moieties have a cis orientation and the angle between the chloride ligands is 93.05°. The imine nitrogen atoms complete the octahedral coordination of the Ti center by occupying the axial positions. The newly synthesized (2 and 4–6) and already known complexes (1 and 3) were introduced in detailed ethene‐polymerization studies. The activities achieved were low to moderate depending on the size and nature of the imino substituents. The polyethenes (PEs) produced had high molar masses, and the modalities of the molecular weight distributions varyied with polymerization temperature. Based on the results of ab initio calculations and on the experimental data obtained, an explanation for uni‐ and bimodal polymerization behavior and the differences in catalytic activities are given. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Lanthanide(III) Chelates of DTPA Bis(amide) Glycoconjugates: Potential Imaging Agents Targeted at the Asyaloglycoprotein Receptor
Authors: Baía Paula , André João P. , Geraldes Carlos F. G. C. , Martins José A. , Merbach André E. , Tóth Éva 
Published: June 2005

AbstractThe synthesis and characterisation of a new class of DTPA bis(amide) linked glycoconjugates of different sugars [lactose (Lac) and galactose (Gal)] and valencies (di and tetra) and their LnIII complexes is reported. The 1H NMR spectra of the SmIII and EuIII complexes of DTPAGal2, DTPAGal4, and DTPALac2, obtained between 7 and 80 °C, indicate that several of the four possible diastereoisomeric pairs of structures resulting from the chirality of the three bound DTPA nitrogen atoms are present in solution, with different relative populations. The dynamic effects of racemisation of the central nitrogen atom in the NMR spectra show that this process is fast at 60 °C for the SmIII complexes and slow at 7 °C for the EuIII complexes. The in vitro r1 nuclear magnetic relaxation dispersion (NMRD) of the water protons of the GdIII–DTPA bis(amide) glycoconjugate containing two lactosyl moieties [GdIII–DTPALac2] was studied, yielding the molecular parameters that govern its relaxivity. Its r1 value, at 25 °C and 20 MHz, is 13 % higher than that reported for GdIII chelates of lower molecular weight DTPA bis(amides), such as DTPA‐BMA, consistent with a five times larger τR value. The water exchange rate, kex, and the electron spin relaxation parameters of the GdIII–DTPALac2 complex are within the usual range for similar GdIII–DTPA bis(amide) chelates. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Crystallographic and Electrochemical Characteristics ofLa0.7Mg0.3Ni4.5–x(Al0.5Mo0.5)x (x = 0–0.8) Hydrogen Storage Alloys
Authors: Zhang Xin‐Bo , Sun Dan‐Zi , Yin Wen‐Ya , Chai Yu‐Jun , Zhao Min‐Shou 
Published: June 2005

AbstractThe structure, hydrogen storage property, and electrochemical characteristics of the La0.7Mg0.3Ni4.5–x(Al0.5Mo0.5)x (x = 0, 0.2, 0.4, 0.6, 0.8) hydrogen storage alloys have been investigated systematically. The X‐ray powder diffraction and Rietveld analysis results reveal that all the alloys mainly consist of the La(La, Mg)2Ni9 phase and the LaNi5 phase. The electrochemical measurements show that the maximum discharge capacity increases first from 246.3 (x = 0) to 345.4 mAh/g (x = 0.6) and then decreases to 317.6 mAh/g (x = 0.8), which is consistent with the variation of the hydrogen storage capacity indicated by the P‐C isotherms. For the discharge current density of 1200 mA/g, the high‐rate dischargeability of the alloy electrodes increases linearly from 47.2 % (x = 0) to 73.8 % (x = 0.8). Moreover, according to the linear polarization curves, the exchange current density of the alloy electrodes also increases monotonously with increasing x. The hydrogen diffusion coefficient increases with increasing Al and Mo content, and thus increases the low‐temperature dischargeability of the alloy electrodes. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Electrochemical Synthesis and Structural Characterisation of Cadmium and Mercury Complexes Containing Pyrimidine‐2‐thionate Ligands
Authors: Rodríguez Antonio , Sousa‐Pedrares Antonio , García‐Vázquez José A. , Romero Jaime , Sousa Antonio 
Published: June 2005

AbstractThe electrochemical oxidation of anodic metal (cadmium or mercury) in a cell containing an acetonitrile solution of the appropriate pyrimidine‐2‐thione (RpymSH) affords complexes [M(RpymS)2] (M = Cd, Hg; R = 4‐CF3, 4,6‐CF3,Me and 4,6‐CF3,Ph). When 2,2'‐bipyridine (bipy) or 1,10‐phenanthroline (phen) was added to the electrolytic cell, adducts of cadmium and compounds with these coligands were obtained. All the compounds have been characterised by microanalysis, IR spectroscopy and, in the case of the compounds that were sufficiently soluble, by 1H, 13C and 199Hg NMR spectroscopy. The compounds [Cd(4‐CF3pymS)2] (1), [Cd(4,6‐CF3MepymS)2(bipy)] (4), [Cd(4,6‐CF3PhpymS)2(phen)] (6) and [Hg(4,6‐CF3MepymS)2] (8) were also characterised by X‐ray diffraction. Compound 1 presents a polymeric structure with the polymer chains interconnected by intermolecular C–H···N interactions. Compounds 4 and 6 adopt mononuclear structures, with weak inter‐ and intramolecular C–H···π interactions, as well as π–π stacking interactions for compound 6. Compound 8 also presents a mononuclear structure with intermolecular π–π interactions between the pyrimidine rings and additional weak Hg···Hg contacts (3.484 Å). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A New Spherical Metallacryptate Compound [Na{Cu6(Thr)8(H2O)2(ClO4)4}]·ClO4·5 H2O: Magnetic Properties and DFT Calculations
Authors: Xiang Sheng‐Chang , Hu Sheng‐Min , Zhang Jian‐Jun , Wu Xin‐Tao , Li Jun‐Qian 
Published: June 2005

AbstractThe hexanuclear copper(II) complex with threoninato acid has been synthesized. Its structure can be described as an octahedron cage with D2h symmetry in which six copper ions are bound by eight threoninato acids with a [3.11223130] coordination mode and one Na+ cation being captured within the center of the cage. In contrast with other hexanuclear copper compounds containing amino acids, the title compound has a prolate Cu6 octahedron with the longest axial distance and a rectangle equatorial plane, as well as special coordinated perchlorate ions. Compared with classic cryptate, hexanuclear copper(II) compounds with amino acids can be regarded as a new topologic type of spherical macrotricyclic metallacryptates [2,2,2,2] whose cages have a high selectivity for sodium ions. The analysis of magnetic susceptibility data shows that the threoninato compound has a ground state with spin S = 3. The computing coupling constant between the equatorial Cu centers and the axial ones is 4.4 cm–1,calculated by using DFT methods for a model compound. This is close to three known experimental values of 1.39, 0.56 or 0.43 cm–1 for complexes with 4‐hydroxy‐L‐prolinato, L‐prolinato or L‐threoninato acid as ligands, respectively. The dominant ferromagnetic interactions for these complexes can be essentially attributed to the orthogonality between the magnetic orbitals, dxz or dyz orbitals for the equatorial CuII centers and d orbitals for the axial ones. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Surface Segregation in SnO2–Fe2O3 Nanopowders and Effects in Mössbauer Spectroscopy
Authors: Castro Ricardo H. R. , Hidalgo Pilar , Coaquira José A. H. , Bettini Jefferson , Zanchet Daniela , Gouvêa Douglas 
Published: June 2005

AbstractSnO2–Fe2O3 nanopowders prepared by the polymeric precursor method were studied by combined conventional and high‐resolution techniques. The powders treated at 500 °C were analyzed by EDS local probe associated with HRTEM to directly detect surface segregation of Fe ions onto SnO2 nanoparticles over a broad range of concentrations. The segregation of these ions controls the system microstructure by changing the surface energies and acting as nucleation sites for the formation of a Fe oxide phase (magnetite) at high Fe concentrations. A technologically interesting core–shell‐type particle structure, with a magnetic shell and semiconductor core, was observed for the first time. The influence of the segregated Fe ions in Mössbauer spectra is also addressed as a new proposal for the interpretation of the effects of composition changes in both the bulk and at the interface of particles. In this proposal, the two observed sites in Mössbauer spectra would be independently related to bulk‐substituted and surface‐segregated Fe ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)